putty/config.c

/*
 * config.c - the platform-independent parts of the PuTTY
 * configuration box.
 */

#include <assert.h>
#include <stdlib.h>

#include "putty.h"
#include "dialog.h"
#include "storage.h"
#include "tree234.h"

#define PRINTER_DISABLED_STRING "None (printing disabled)"

#define HOST_BOX_TITLE "Host Name (or IP address)"
#define PORT_BOX_TITLE "Port"

void conf_radiobutton_handler(dlgcontrol *ctrl, dlgparam *dlg,
                              void *data, int event)
{
    int button;
    Conf *conf = (Conf *)data;

    /*
     * For a standard radio button set, the context parameter gives
     * the primary key (CONF_foo), and the extra data per button
     * gives the value the target field should take if that button
     * is the one selected.
     */
    if (event == EVENT_REFRESH) {
        int val = conf_get_int(conf, ctrl->context.i);
        for (button = 0; button < ctrl->radio.nbuttons; button++)
            if (val == ctrl->radio.buttondata[button].i)
                break;
        /* We expected that `break' to happen, in all circumstances. */
        assert(button < ctrl->radio.nbuttons);
        dlg_radiobutton_set(ctrl, dlg, button);
    } else if (event == EVENT_VALCHANGE) {
        button = dlg_radiobutton_get(ctrl, dlg);
        assert(button >= 0 && button < ctrl->radio.nbuttons);
        conf_set_int(conf, ctrl->context.i,
                     ctrl->radio.buttondata[button].i);
    }
}

void conf_radiobutton_bool_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                   void *data, int event)
{
    int button;
    Conf *conf = (Conf *)data;

    /*
     * Same as conf_radiobutton_handler, but using conf_set_bool in
     * place of conf_set_int, because it's dealing with a bool-typed
     * config option.
     */
    if (event == EVENT_REFRESH) {
        int val = conf_get_bool(conf, ctrl->context.i);
        for (button = 0; button < ctrl->radio.nbuttons; button++)
            if (val == ctrl->radio.buttondata[button].i)
                break;
        /* We expected that `break' to happen, in all circumstances. */
        assert(button < ctrl->radio.nbuttons);
        dlg_radiobutton_set(ctrl, dlg, button);
    } else if (event == EVENT_VALCHANGE) {
        button = dlg_radiobutton_get(ctrl, dlg);
        assert(button >= 0 && button < ctrl->radio.nbuttons);
        conf_set_bool(conf, ctrl->context.i,
                      ctrl->radio.buttondata[button].i);
    }
}

#define CHECKBOX_INVERT (1<<30)
void conf_checkbox_handler(dlgcontrol *ctrl, dlgparam *dlg,
                           void *data, int event)
{
    int key;
    bool invert;
    Conf *conf = (Conf *)data;

    /*
     * For a standard checkbox, the context parameter gives the
     * primary key (CONF_foo), optionally ORed with CHECKBOX_INVERT.
     */
    key = ctrl->context.i;
    if (key & CHECKBOX_INVERT) {
        key &= ~CHECKBOX_INVERT;
        invert = true;
    } else
        invert = false;

    /*
     * C lacks a logical XOR, so the following code uses the idiom
     * (!a ^ !b) to obtain the logical XOR of a and b. (That is, 1
     * iff exactly one of a and b is nonzero, otherwise 0.)
     */

    if (event == EVENT_REFRESH) {
        bool val = conf_get_bool(conf, key);
        dlg_checkbox_set(ctrl, dlg, (!val ^ !invert));
    } else if (event == EVENT_VALCHANGE) {
        conf_set_bool(conf, key, !dlg_checkbox_get(ctrl,dlg) ^ !invert);
    }
}

const struct conf_editbox_handler_type conf_editbox_str = {.type = EDIT_STR};
const struct conf_editbox_handler_type conf_editbox_int = {.type = EDIT_INT};

void conf_editbox_handler(dlgcontrol *ctrl, dlgparam *dlg,
                          void *data, int event)
{
    /*
     * The standard edit-box handler expects the main `context' field
     * to contain the primary key. The secondary `context2' field is a
     * pointer to the struct conf_editbox_handler_type defined in
     * putty.h.
     */
    int key = ctrl->context.i;
    const struct conf_editbox_handler_type *type = ctrl->context2.cp;
    Conf *conf = (Conf *)data;

    if (type->type == EDIT_STR) {
        if (event == EVENT_REFRESH) {
            bool utf8;
            char *field = conf_get_str_ambi(conf, key, &utf8);
            if (utf8)
                dlg_editbox_set_utf8(ctrl, dlg, field);
            else
                dlg_editbox_set(ctrl, dlg, field);
        } else if (event == EVENT_VALCHANGE) {
            char *field = dlg_editbox_get_utf8(ctrl, dlg);
            if (!conf_try_set_utf8(conf, key, field)) {
                sfree(field);
                field = dlg_editbox_get(ctrl, dlg);
                conf_set_str(conf, key, field);
            }
            sfree(field);
        }
    } else {
        if (event == EVENT_REFRESH) {
            char str[80];
            int value = conf_get_int(conf, key);
            if (type->type == EDIT_INT)
                sprintf(str, "%d", value);
            else
                sprintf(str, "%g", (double)value / type->denominator);
            dlg_editbox_set(ctrl, dlg, str);
        } else if (event == EVENT_VALCHANGE) {
            char *str = dlg_editbox_get(ctrl, dlg);
            if (type->type == EDIT_INT)
                conf_set_int(conf, key, atoi(str));
            else
                conf_set_int(conf, key, (int)(type->denominator * atof(str)));
            sfree(str);
        }
    }
}

void conf_filesel_handler(dlgcontrol *ctrl, dlgparam *dlg,
                          void *data, int event)
{
    int key = ctrl->context.i;
    Conf *conf = (Conf *)data;

    if (event == EVENT_REFRESH) {
        dlg_filesel_set(
            ctrl, dlg, conf_get_filename(conf, key));
    } else if (event == EVENT_VALCHANGE) {
        Filename *filename = dlg_filesel_get(ctrl, dlg);
        conf_set_filename(conf, key, filename);
        filename_free(filename);
    }
}

void conf_fontsel_handler(dlgcontrol *ctrl, dlgparam *dlg,
                          void *data, int event)
{
    int key = ctrl->context.i;
    Conf *conf = (Conf *)data;

    if (event == EVENT_REFRESH) {
        dlg_fontsel_set(
            ctrl, dlg, conf_get_fontspec(conf, key));
    } else if (event == EVENT_VALCHANGE) {
        FontSpec *fontspec = dlg_fontsel_get(ctrl, dlg);
        conf_set_fontspec(conf, key, fontspec);
        fontspec_free(fontspec);
    }
}

static void config_host_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                void *data, int event)
{
    Conf *conf = (Conf *)data;

    /*
     * This function works just like the standard edit box handler,
     * only it has to choose the control's label and text from two
     * different places depending on the protocol.
     */
    if (event == EVENT_REFRESH) {
        if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL) {
            /*
             * This label text is carefully chosen to contain an n,
             * since that's the shortcut for the host name control.
             */
            dlg_label_change(ctrl, dlg, "Serial line");
            dlg_editbox_set(ctrl, dlg, conf_get_str(conf, CONF_serline));
        } else {
            dlg_label_change(ctrl, dlg, HOST_BOX_TITLE);
            dlg_editbox_set(ctrl, dlg, conf_get_str(conf, CONF_host));
        }
    } else if (event == EVENT_VALCHANGE) {
        char *s = dlg_editbox_get(ctrl, dlg);
        if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL)
            conf_set_str(conf, CONF_serline, s);
        else
            conf_set_str(conf, CONF_host, s);
        sfree(s);
    }
}

static void config_port_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                void *data, int event)
{
    Conf *conf = (Conf *)data;
    char buf[80];

    /*
     * This function works similarly to the standard edit box handler,
     * only it has to choose the control's label and text from two
     * different places depending on the protocol.
     */
    if (event == EVENT_REFRESH) {
        if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL) {
            /*
             * This label text is carefully chosen to contain a p,
             * since that's the shortcut for the port control.
             */
            dlg_label_change(ctrl, dlg, "Speed");
            sprintf(buf, "%d", conf_get_int(conf, CONF_serspeed));
        } else {
            dlg_label_change(ctrl, dlg, PORT_BOX_TITLE);
            if (conf_get_int(conf, CONF_port) != 0)
                sprintf(buf, "%d", conf_get_int(conf, CONF_port));
            else
                /* Display an (invalid) port of 0 as blank */
                buf[0] = '\0';
        }
        dlg_editbox_set(ctrl, dlg, buf);
    } else if (event == EVENT_VALCHANGE) {
        char *s = dlg_editbox_get(ctrl, dlg);
        int i = atoi(s);
        sfree(s);

        if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL)
            conf_set_int(conf, CONF_serspeed, i);
        else
            conf_set_int(conf, CONF_port, i);
    }
}

struct hostport {
    dlgcontrol *host, *port, *protradio, *protlist;
    bool mid_refresh;
};

/*
 * Shared handler for protocol radio-button and drop-list controls.
 * Handles the interaction of those two controls, and also changes
 * the setting of the port box to match the protocol if necessary,
 * and refreshes both host and port boxes when switching to/from the
 * serial backend.
 */
static void config_protocols_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                     void *data, int event)
{
    Conf *conf = (Conf *)data;
    int curproto = conf_get_int(conf, CONF_protocol);
    struct hostport *hp = (struct hostport *)ctrl->context.p;

    if (event == EVENT_REFRESH) {
        /*
         * Refresh the states of the controls from Conf.
         *
         * When refreshing these controls, we have to watch out for
         * re-entrancy: because there are two controls involved, the
         * refresh is not atomic, so the VALCHANGE and/or SELCHANGE
         * callbacks resulting from our updates here might cause other
         * settings here to change unwantedly. (E.g. setting the list
         * selection shouldn't trigger the SELCHANGE side effect of
         * selecting the Other radio button; setting the radio button
         * to Other here shouldn't have the side effect of selecting
         * whatever protocol is _currently_ selected in the list box,
         * if we haven't selected the right one yet.)
         */
        hp->mid_refresh = true;

        if (ctrl == hp->protradio) {
            /* Available buttons were set up when control was created.
             * Just select one of them, possibly. */
            for (int button = 0; button < ctrl->radio.nbuttons; button++)
                /* The final button is "Other:". If we reach that one, the
                 * current protocol must be in the drop list, so we should
                 * select the "Other:" button. */
                if (curproto == ctrl->radio.buttondata[button].i ||
                    button == ctrl->radio.nbuttons-1) {
                    dlg_radiobutton_set(ctrl, dlg, button);
                    break;
                }
        } else if (ctrl == hp->protlist) {
            int curentry = -1;
            dlg_update_start(ctrl, dlg);
            dlg_listbox_clear(ctrl, dlg);
            assert(n_ui_backends > 0 && n_ui_backends < PROTOCOL_LIMIT);
            for (size_t i = n_ui_backends;
                 i < PROTOCOL_LIMIT && backends[i]; i++) {
                dlg_listbox_addwithid(ctrl, dlg,
                                      backends[i]->displayname_tc,
                                      backends[i]->protocol);
                if (backends[i]->protocol == curproto)
                    curentry = i - n_ui_backends;
            }
            if (curentry > 0) {
                /*
                 * The currently configured protocol is one of the
                 * list-box ones, so select it in protlist.
                 *
                 * (The corresponding refresh event for protradio
                 * should have selected the "Other:" radio button, to
                 * keep things consistent.)
                 */
                dlg_listbox_select(ctrl, dlg, curentry);
            } else {
                /*
                 * If the currently configured protocol is one of the
                 * radio buttons, we must still ensure *something* is
                 * selected in the list box. The sensible default is
                 * the first list element, which be_*.c ought to have
                 * arranged to be the 'runner-up' in protocol
                 * popularity out of the ones relegated to the list
                 * box.
                 *
                 * We don't make much effort to retain the state of
                 * the list box when it doesn't correspond to an
                 * actual protocol. So it's easy for this case to be
                 * reached as a side effect of other actions, e.g.
                 * loading a saved session that has a radio-button
                 * protocol configured.
                 */
                dlg_listbox_select(ctrl, dlg, 0);
            }
            dlg_update_done(ctrl, dlg);
        }

        hp->mid_refresh = false;
    } else if (!hp->mid_refresh) {
        /*
         * Potentially update Conf from the states of the controls.
         */
        int newproto = curproto;

        if (event == EVENT_VALCHANGE && ctrl == hp->protradio) {
            int button = dlg_radiobutton_get(ctrl, dlg);
            assert(button >= 0 && button < ctrl->radio.nbuttons);
            if (ctrl->radio.buttondata[button].i == -1) {
                /*
                 * The 'Other' radio button was selected, which means we
                 * have to set CONF_protocol based on the currently
                 * selected list box entry.
                 *
                 * (We conditionalise this on there _being_ a selected
                 * list box entry. I hope the case where nothing is
                 * selected can't actually come up except during
                 * initialisation, and I also hope that hp->mid_session
                 * will prevent that case from getting here. But as a
                 * last-ditch fallback, this if statement should at least
                 * guarantee that we don't pass a nonsense value to
                 * dlg_listbox_getid.)
                 */
                int i = dlg_listbox_index(hp->protlist, dlg);
                if (i >= 0)
                    newproto = dlg_listbox_getid(hp->protlist, dlg, i);
            } else {
                newproto = ctrl->radio.buttondata[button].i;
            }
        } else if (event == EVENT_SELCHANGE && ctrl == hp->protlist) {
            int i = dlg_listbox_index(ctrl, dlg);
            if (i >= 0) {
                newproto = dlg_listbox_getid(ctrl, dlg, i);
                /* Select the "Other" radio button, too */
                dlg_radiobutton_set(hp->protradio, dlg,
                                    hp->protradio->radio.nbuttons-1);
            }
        }

        if (newproto != curproto) {
            conf_set_int(conf, CONF_protocol, newproto);

            const struct BackendVtable *cvt = backend_vt_from_proto(curproto);
            const struct BackendVtable *nvt = backend_vt_from_proto(newproto);
            assert(cvt);
            assert(nvt);
            /*
             * Iff the user hasn't changed the port from the old
             * protocol's default, update it with the new protocol's
             * default.
             *
             * (This includes a "default" of 0, implying that there is
             * no sensible default for that protocol; in this case
             * it's displayed as a blank.)
             *
             * This helps with the common case of tabbing through the
             * controls in order and setting a non-default port before
             * getting to the protocol; we want that non-default port
             * to be preserved.
             */
            int port = conf_get_int(conf, CONF_port);
            if (port == cvt->default_port)
                conf_set_int(conf, CONF_port, nvt->default_port);

            dlg_refresh(hp->host, dlg);
            dlg_refresh(hp->port, dlg);
        }
    }
}

static void loggingbuttons_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                   void *data, int event)
{
    int button;
    Conf *conf = (Conf *)data;
    /* This function works just like the standard radio-button handler,
     * but it has to fall back to "no logging" in situations where the
     * configured logging type isn't applicable.
     */
    if (event == EVENT_REFRESH) {
        int logtype = conf_get_int(conf, CONF_logtype);

        for (button = 0; button < ctrl->radio.nbuttons; button++)
            if (logtype == ctrl->radio.buttondata[button].i)
                break;

        /* We fell off the end, so we lack the configured logging type */
        if (button == ctrl->radio.nbuttons) {
            button = 0;
            conf_set_int(conf, CONF_logtype, LGTYP_NONE);
        }
        dlg_radiobutton_set(ctrl, dlg, button);
    } else if (event == EVENT_VALCHANGE) {
        button = dlg_radiobutton_get(ctrl, dlg);
        assert(button >= 0 && button < ctrl->radio.nbuttons);
        conf_set_int(conf, CONF_logtype, ctrl->radio.buttondata[button].i);
    }
}

static void numeric_keypad_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                   void *data, int event)
{
    int button;
    Conf *conf = (Conf *)data;
    /*
     * This function works much like the standard radio button
     * handler, but it has to handle two fields in Conf.
     */
    if (event == EVENT_REFRESH) {
        if (conf_get_bool(conf, CONF_nethack_keypad))
            button = 2;
        else if (conf_get_bool(conf, CONF_app_keypad))
            button = 1;
        else
            button = 0;
        assert(button < ctrl->radio.nbuttons);
        dlg_radiobutton_set(ctrl, dlg, button);
    } else if (event == EVENT_VALCHANGE) {
        button = dlg_radiobutton_get(ctrl, dlg);
        assert(button >= 0 && button < ctrl->radio.nbuttons);
        if (button == 2) {
            conf_set_bool(conf, CONF_app_keypad, false);
            conf_set_bool(conf, CONF_nethack_keypad, true);
        } else {
            conf_set_bool(conf, CONF_app_keypad, (button != 0));
            conf_set_bool(conf, CONF_nethack_keypad, false);
        }
    }
}

static void cipherlist_handler(dlgcontrol *ctrl, dlgparam *dlg,
                               void *data, int event)
{
    Conf *conf = (Conf *)data;
    if (event == EVENT_REFRESH) {
        int i;

        static const struct { const char *s; int c; } ciphers[] = {
            { "ChaCha20 (SSH-2 only)",  CIPHER_CHACHA20 },
            { "AES-GCM (SSH-2 only)",   CIPHER_AESGCM },
            { "3DES",                   CIPHER_3DES },
            { "Blowfish",               CIPHER_BLOWFISH },
            { "DES",                    CIPHER_DES },
            { "AES (SSH-2 only)",       CIPHER_AES },
            { "Arcfour (SSH-2 only)",   CIPHER_ARCFOUR },
            { "-- warn below here --",  CIPHER_WARN }
        };

        /* Set up the "selected ciphers" box. */
        /* (cipherlist assumed to contain all ciphers) */
        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);
        for (i = 0; i < CIPHER_MAX; i++) {
            int c = conf_get_int_int(conf, CONF_ssh_cipherlist, i);
            int j;
            const char *cstr = NULL;
            for (j = 0; j < (sizeof ciphers) / (sizeof ciphers[0]); j++) {
                if (ciphers[j].c == c) {
                    cstr = ciphers[j].s;
                    break;
                }
            }
            dlg_listbox_addwithid(ctrl, dlg, cstr, c);
        }
        dlg_update_done(ctrl, dlg);

    } else if (event == EVENT_VALCHANGE) {
        int i;

        /* Update array to match the list box. */
        for (i=0; i < CIPHER_MAX; i++)
            conf_set_int_int(conf, CONF_ssh_cipherlist, i,
                             dlg_listbox_getid(ctrl, dlg, i));
    }
}

#ifndef NO_GSSAPI
static void gsslist_handler(dlgcontrol *ctrl, dlgparam *dlg,
                            void *data, int event)
{
    Conf *conf = (Conf *)data;
    if (event == EVENT_REFRESH) {
        int i;

        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);
        for (i = 0; i < ngsslibs; i++) {
            int id = conf_get_int_int(conf, CONF_ssh_gsslist, i);
            assert(id >= 0 && id < ngsslibs);
            dlg_listbox_addwithid(ctrl, dlg, gsslibnames[id], id);
        }
        dlg_update_done(ctrl, dlg);

    } else if (event == EVENT_VALCHANGE) {
        int i;

        /* Update array to match the list box. */
        for (i=0; i < ngsslibs; i++)
            conf_set_int_int(conf, CONF_ssh_gsslist, i,
                             dlg_listbox_getid(ctrl, dlg, i));
    }
}
#endif

static void kexlist_handler(dlgcontrol *ctrl, dlgparam *dlg,
                            void *data, int event)
{
    Conf *conf = (Conf *)data;
    if (event == EVENT_REFRESH) {
        int i;

        static const struct { const char *s; int k; } kexes[] = {
            { "Diffie-Hellman group 1 (1024-bit)",  KEX_DHGROUP1 },
            { "Diffie-Hellman group 14 (2048-bit)", KEX_DHGROUP14 },
            { "Diffie-Hellman group 15 (3072-bit)", KEX_DHGROUP15 },
            { "Diffie-Hellman group 16 (4096-bit)", KEX_DHGROUP16 },
            { "Diffie-Hellman group 17 (6144-bit)", KEX_DHGROUP17 },
            { "Diffie-Hellman group 18 (8192-bit)", KEX_DHGROUP18 },
            { "Diffie-Hellman group exchange",      KEX_DHGEX },
            { "RSA-based key exchange",             KEX_RSA },
            { "ECDH key exchange",                  KEX_ECDH },
            { "NTRU Prime / Curve25519 hybrid kex", KEX_NTRU_HYBRID },
            { "ML-KEM / Curve25519 hybrid kex",     KEX_MLKEM_25519_HYBRID },
            { "ML-KEM / NIST ECDH hybrid kex",      KEX_MLKEM_NIST_HYBRID },
            { "-- warn below here --",              KEX_WARN }
        };

        /* Set up the "kex preference" box. */
        /* (kexlist assumed to contain all algorithms) */
        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);
        for (i = 0; i < KEX_MAX; i++) {
            int k = conf_get_int_int(conf, CONF_ssh_kexlist, i);
            int j;
            const char *kstr = NULL;
            for (j = 0; j < (sizeof kexes) / (sizeof kexes[0]); j++) {
                if (kexes[j].k == k) {
                    kstr = kexes[j].s;
                    break;
                }
            }
            dlg_listbox_addwithid(ctrl, dlg, kstr, k);
        }
        dlg_update_done(ctrl, dlg);

    } else if (event == EVENT_VALCHANGE) {
        int i;

        /* Update array to match the list box. */
        for (i=0; i < KEX_MAX; i++)
            conf_set_int_int(conf, CONF_ssh_kexlist, i,
                             dlg_listbox_getid(ctrl, dlg, i));
    }
}

static void hklist_handler(dlgcontrol *ctrl, dlgparam *dlg,
                           void *data, int event)
{
    Conf *conf = (Conf *)data;
    if (event == EVENT_REFRESH) {
        int i;

        static const struct { const char *s; int k; } hks[] = {
            { "Ed25519",               HK_ED25519 },
            { "Ed448",                 HK_ED448 },
            { "ECDSA",                 HK_ECDSA },
            { "DSA",                   HK_DSA },
            { "RSA",                   HK_RSA },
            { "-- warn below here --", HK_WARN }
        };

        /* Set up the "host key preference" box. */
        /* (hklist assumed to contain all algorithms) */
        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);
        for (i = 0; i < HK_MAX; i++) {
            int k = conf_get_int_int(conf, CONF_ssh_hklist, i);
            int j;
            const char *kstr = NULL;
            for (j = 0; j < lenof(hks); j++) {
                if (hks[j].k == k) {
                    kstr = hks[j].s;
                    break;
                }
            }
            dlg_listbox_addwithid(ctrl, dlg, kstr, k);
        }
        dlg_update_done(ctrl, dlg);

    } else if (event == EVENT_VALCHANGE) {
        int i;

        /* Update array to match the list box. */
        for (i=0; i < HK_MAX; i++)
            conf_set_int_int(conf, CONF_ssh_hklist, i,
                             dlg_listbox_getid(ctrl, dlg, i));
    }
}

static void printerbox_handler(dlgcontrol *ctrl, dlgparam *dlg,
                               void *data, int event)
{
    Conf *conf = (Conf *)data;
    if (event == EVENT_REFRESH) {
        int nprinters, i;
        printer_enum *pe;
        const char *printer;

        dlg_update_start(ctrl, dlg);
        /*
         * Some backends may wish to disable the drop-down list on
         * this edit box. Be prepared for this.
         */
        if (ctrl->editbox.has_list) {
            dlg_listbox_clear(ctrl, dlg);
            dlg_listbox_add(ctrl, dlg, PRINTER_DISABLED_STRING);
            pe = printer_start_enum(&nprinters);
            for (i = 0; i < nprinters; i++)
                dlg_listbox_add(ctrl, dlg, printer_get_name(pe, i));
            printer_finish_enum(pe);
        }
        printer = conf_get_str(conf, CONF_printer);
        if (!printer)
            printer = PRINTER_DISABLED_STRING;
        dlg_editbox_set(ctrl, dlg, printer);
        dlg_update_done(ctrl, dlg);
    } else if (event == EVENT_VALCHANGE) {
        char *printer = dlg_editbox_get(ctrl, dlg);
        if (!strcmp(printer, PRINTER_DISABLED_STRING))
            printer[0] = '\0';
        conf_set_str(conf, CONF_printer, printer);
        sfree(printer);
    }
}

static void codepage_handler(dlgcontrol *ctrl, dlgparam *dlg,
                             void *data, int event)
{
    Conf *conf = (Conf *)data;
    if (event == EVENT_REFRESH) {
        int i;
        const char *cp, *thiscp;
        dlg_update_start(ctrl, dlg);
        thiscp = cp_name(decode_codepage(conf_get_str(conf,
                                                      CONF_line_codepage)));
        dlg_listbox_clear(ctrl, dlg);
        for (i = 0; (cp = cp_enumerate(i)) != NULL; i++)
            dlg_listbox_add(ctrl, dlg, cp);
        dlg_editbox_set(ctrl, dlg, thiscp);
        conf_set_str(conf, CONF_line_codepage, thiscp);
        dlg_update_done(ctrl, dlg);
    } else if (event == EVENT_VALCHANGE) {
        char *codepage = dlg_editbox_get(ctrl, dlg);
        conf_set_str(conf, CONF_line_codepage,
                     cp_name(decode_codepage(codepage)));
        sfree(codepage);
    }
}

static void sshbug_handler(dlgcontrol *ctrl, dlgparam *dlg,
                           void *data, int event)
{
    Conf *conf = (Conf *)data;
    if (event == EVENT_REFRESH) {
        /*
         * We must fetch the previously configured value from the Conf
         * before we start modifying the drop-down list, otherwise the
         * spurious SELCHANGE we trigger in the process will overwrite
         * the value we wanted to keep.
         */
        int oldconf = conf_get_int(conf, ctrl->context.i);
        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);
        dlg_listbox_addwithid(ctrl, dlg, "Auto", AUTO);
        dlg_listbox_addwithid(ctrl, dlg, "Off", FORCE_OFF);
        dlg_listbox_addwithid(ctrl, dlg, "On", FORCE_ON);
        switch (oldconf) {
          case AUTO:      dlg_listbox_select(ctrl, dlg, 0); break;
          case FORCE_OFF: dlg_listbox_select(ctrl, dlg, 1); break;
          case FORCE_ON:  dlg_listbox_select(ctrl, dlg, 2); break;
        }
        dlg_update_done(ctrl, dlg);
    } else if (event == EVENT_SELCHANGE) {
        int i = dlg_listbox_index(ctrl, dlg);
        if (i < 0)
            i = AUTO;
        else
            i = dlg_listbox_getid(ctrl, dlg, i);
        conf_set_int(conf, ctrl->context.i, i);
    }
}

static void sshbug_handler_manual_only(dlgcontrol *ctrl, dlgparam *dlg,
                                       void *data, int event)
{
    /*
     * This is just like sshbug_handler, except that there's no 'Auto'
     * option. Used for bug workaround flags that can't be
     * autodetected, and have to be manually enabled if they're to be
     * used at all.
     */
    Conf *conf = (Conf *)data;
    if (event == EVENT_REFRESH) {
        int oldconf = conf_get_int(conf, ctrl->context.i);
        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);
        dlg_listbox_addwithid(ctrl, dlg, "Off", FORCE_OFF);
        dlg_listbox_addwithid(ctrl, dlg, "On", FORCE_ON);
        switch (oldconf) {
          case FORCE_OFF: dlg_listbox_select(ctrl, dlg, 0); break;
          case FORCE_ON:  dlg_listbox_select(ctrl, dlg, 1); break;
        }
        dlg_update_done(ctrl, dlg);
    } else if (event == EVENT_SELCHANGE) {
        int i = dlg_listbox_index(ctrl, dlg);
        if (i < 0)
            i = FORCE_OFF;
        else
            i = dlg_listbox_getid(ctrl, dlg, i);
        conf_set_int(conf, ctrl->context.i, i);
    }
}

struct sessionsaver_data {
    dlgcontrol *editbox, *listbox, *loadbutton, *savebutton, *delbutton;
    dlgcontrol *okbutton, *cancelbutton;
    struct sesslist sesslist;
    bool midsession;
    char *savedsession;     /* the current contents of ssd->editbox */
};

static void sessionsaver_data_free(void *ssdv)
{
    struct sessionsaver_data *ssd = (struct sessionsaver_data *)ssdv;
    get_sesslist(&ssd->sesslist, false);
    sfree(ssd->savedsession);
    sfree(ssd);
}

/*
 * Helper function to load the session selected in the list box, if
 * any, as this is done in more than one place below. Returns 0 for
 * failure.
 */
static bool load_selected_session(
    struct sessionsaver_data *ssd,
    dlgparam *dlg, Conf *conf, bool *maybe_launch)
{
    int i = dlg_listbox_index(ssd->listbox, dlg);
    bool isdef;
    if (i < 0) {
        dlg_beep(dlg);
        return false;
    }
    isdef = !strcmp(ssd->sesslist.sessions[i], "Default Settings");
    load_settings(ssd->sesslist.sessions[i], conf);
    sfree(ssd->savedsession);
    ssd->savedsession = dupstr(isdef ? "" : ssd->sesslist.sessions[i]);
    if (maybe_launch)
        *maybe_launch = !isdef;
    dlg_refresh(NULL, dlg);
    /* Restore the selection, which might have been clobbered by
     * changing the value of the edit box. */
    dlg_listbox_select(ssd->listbox, dlg, i);
    return true;
}

static void sessionsaver_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                 void *data, int event)
{
    Conf *conf = (Conf *)data;
    struct sessionsaver_data *ssd =
        (struct sessionsaver_data *)ctrl->context.p;

    if (event == EVENT_REFRESH) {
        if (ctrl == ssd->editbox) {
            dlg_editbox_set(ctrl, dlg, ssd->savedsession);
        } else if (ctrl == ssd->listbox) {
            int i;
            dlg_update_start(ctrl, dlg);
            dlg_listbox_clear(ctrl, dlg);
            for (i = 0; i < ssd->sesslist.nsessions; i++)
                dlg_listbox_add(ctrl, dlg, ssd->sesslist.sessions[i]);
            dlg_update_done(ctrl, dlg);
        }
    } else if (event == EVENT_VALCHANGE) {
        int top, bottom, halfway, i;
        if (ctrl == ssd->editbox) {
            sfree(ssd->savedsession);
            ssd->savedsession = dlg_editbox_get(ctrl, dlg);
            top = ssd->sesslist.nsessions;
            bottom = -1;
            while (top-bottom > 1) {
                halfway = (top+bottom)/2;
                i = strcmp(ssd->savedsession, ssd->sesslist.sessions[halfway]);
                if (i <= 0 ) {
                    top = halfway;
                } else {
                    bottom = halfway;
                }
            }
            if (top == ssd->sesslist.nsessions) {
                top -= 1;
            }
            dlg_listbox_select(ssd->listbox, dlg, top);
        }
    } else if (event == EVENT_ACTION) {
        bool mbl = false;
        if (!ssd->midsession &&
            (ctrl == ssd->listbox ||
             (ssd->loadbutton && ctrl == ssd->loadbutton))) {
            /*
             * The user has double-clicked a session, or hit Load.
             * We must load the selected session, and then
             * terminate the configuration dialog _if_ there was a
             * double-click on the list box _and_ that session
             * contains a hostname.
             */
            if (load_selected_session(ssd, dlg, conf, &mbl) &&
                (mbl && ctrl == ssd->listbox && conf_launchable(conf))) {
                dlg_end(dlg, 1);       /* it's all over, and succeeded */
            }
        } else if (ctrl == ssd->savebutton) {
            bool isdef = !strcmp(ssd->savedsession, "Default Settings");
            if (!ssd->savedsession[0]) {
                int i = dlg_listbox_index(ssd->listbox, dlg);
                if (i < 0) {
                    dlg_beep(dlg);
                    return;
                }
                isdef = !strcmp(ssd->sesslist.sessions[i], "Default Settings");
                sfree(ssd->savedsession);
                ssd->savedsession = dupstr(isdef ? "" :
                                           ssd->sesslist.sessions[i]);
            }
            {
                char *errmsg = save_settings(ssd->savedsession, conf);
                if (errmsg) {
                    dlg_error_msg(dlg, errmsg);
                    sfree(errmsg);
                }
            }
            get_sesslist(&ssd->sesslist, false);
            get_sesslist(&ssd->sesslist, true);
            dlg_refresh(ssd->editbox, dlg);
            dlg_refresh(ssd->listbox, dlg);
        } else if (!ssd->midsession &&
                   ssd->delbutton && ctrl == ssd->delbutton) {
            int i = dlg_listbox_index(ssd->listbox, dlg);
            if (i <= 0) {
                dlg_beep(dlg);
            } else {
                del_settings(ssd->sesslist.sessions[i]);
                get_sesslist(&ssd->sesslist, false);
                get_sesslist(&ssd->sesslist, true);
                dlg_refresh(ssd->listbox, dlg);
            }
        } else if (ctrl == ssd->okbutton) {
            if (ssd->midsession) {
                /* In a mid-session Change Settings, Apply is always OK. */
                dlg_end(dlg, 1);
                return;
            }
            /*
             * Annoying special case. If the `Open' button is
             * pressed while no host name is currently set, _and_
             * the session list previously had the focus, _and_
             * there was a session selected in that which had a
             * valid host name in it, then load it and go.
             */
            if (dlg_last_focused(ctrl, dlg) == ssd->listbox &&
                !conf_launchable(conf) && dlg_is_visible(ssd->listbox, dlg)) {
                Conf *conf2 = conf_new();
                bool mbl = false;
                if (!load_selected_session(ssd, dlg, conf2, &mbl)) {
                    dlg_beep(dlg);
                    conf_free(conf2);
                    return;
                }
                /* If at this point we have a valid session, go! */
                if (mbl && conf_launchable(conf2)) {
                    conf_copy_into(conf, conf2);
                    dlg_end(dlg, 1);
                } else
                    dlg_beep(dlg);

                conf_free(conf2);
                return;
            }

            /*
             * Otherwise, do the normal thing: if we have a valid
             * session, get going.
             */
            if (conf_launchable(conf)) {
                dlg_end(dlg, 1);
            } else
                dlg_beep(dlg);
        } else if (ctrl == ssd->cancelbutton) {
            dlg_end(dlg, 0);
        }
    }
}

struct charclass_data {
    dlgcontrol *listbox, *editbox, *button;
};

static void charclass_handler(dlgcontrol *ctrl, dlgparam *dlg,
                              void *data, int event)
{
    Conf *conf = (Conf *)data;
    struct charclass_data *ccd =
        (struct charclass_data *)ctrl->context.p;

    if (event == EVENT_REFRESH) {
        if (ctrl == ccd->listbox) {
            int i;
            dlg_update_start(ctrl, dlg);
            dlg_listbox_clear(ctrl, dlg);
            for (i = 0; i < 128; i++) {
                char str[100];
                sprintf(str, "%d\t(0x%02X)\t%c\t%d", i, i,
                        (i >= 0x21 && i != 0x7F) ? i : ' ',
                        conf_get_int_int(conf, CONF_wordness, i));
                dlg_listbox_add(ctrl, dlg, str);
            }
            dlg_update_done(ctrl, dlg);
        }
    } else if (event == EVENT_ACTION) {
        if (ctrl == ccd->button) {
            char *str;
            int i, n;
            str = dlg_editbox_get(ccd->editbox, dlg);
            n = atoi(str);
            sfree(str);
            for (i = 0; i < 128; i++) {
                if (dlg_listbox_issel(ccd->listbox, dlg, i))
                    conf_set_int_int(conf, CONF_wordness, i, n);
            }
            dlg_refresh(ccd->listbox, dlg);
        }
    }
}

struct colour_data {
    dlgcontrol *listbox, *redit, *gedit, *bedit, *button;
};

/* Array of the user-visible colour names defined in the list macro in
 * putty.h */
static const char *const colours[] = {
    #define CONF_COLOUR_NAME_DECL(id,name) name,
    CONF_COLOUR_LIST(CONF_COLOUR_NAME_DECL)
    #undef CONF_COLOUR_NAME_DECL
};

static void colour_handler(dlgcontrol *ctrl, dlgparam *dlg,
                            void *data, int event)
{
    Conf *conf = (Conf *)data;
    struct colour_data *cd =
        (struct colour_data *)ctrl->context.p;
    bool update = false, clear = false;
    int r, g, b;

    if (event == EVENT_REFRESH) {
        if (ctrl == cd->listbox) {
            int i;
            dlg_update_start(ctrl, dlg);
            dlg_listbox_clear(ctrl, dlg);
            for (i = 0; i < lenof(colours); i++)
                dlg_listbox_add(ctrl, dlg, colours[i]);
            dlg_update_done(ctrl, dlg);
            clear = true;
            update = true;
        }
    } else if (event == EVENT_SELCHANGE) {
        if (ctrl == cd->listbox) {
            /* The user has selected a colour. Update the RGB text. */
            int i = dlg_listbox_index(ctrl, dlg);
            if (i < 0) {
                clear = true;
            } else {
                clear = false;
                r = conf_get_int_int(conf, CONF_colours, i*3+0);
                g = conf_get_int_int(conf, CONF_colours, i*3+1);
                b = conf_get_int_int(conf, CONF_colours, i*3+2);
            }
            update = true;
        }
    } else if (event == EVENT_VALCHANGE) {
        if (ctrl == cd->redit || ctrl == cd->gedit || ctrl == cd->bedit) {
            /* The user has changed the colour using the edit boxes. */
            char *str;
            int i, cval;

            str = dlg_editbox_get(ctrl, dlg);
            cval = atoi(str);
            sfree(str);
            if (cval > 255) cval = 255;
            if (cval < 0)   cval = 0;

            i = dlg_listbox_index(cd->listbox, dlg);
            if (i >= 0) {
                if (ctrl == cd->redit)
                    conf_set_int_int(conf, CONF_colours, i*3+0, cval);
                else if (ctrl == cd->gedit)
                    conf_set_int_int(conf, CONF_colours, i*3+1, cval);
                else if (ctrl == cd->bedit)
                    conf_set_int_int(conf, CONF_colours, i*3+2, cval);
            }
        }
    } else if (event == EVENT_ACTION) {
        if (ctrl == cd->button) {
            int i = dlg_listbox_index(cd->listbox, dlg);
            if (i < 0) {
                dlg_beep(dlg);
                return;
            }
            /*
             * Start a colour selector, which will send us an
             * EVENT_CALLBACK when it's finished and allow us to
             * pick up the results.
             */
            dlg_coloursel_start(ctrl, dlg,
                                conf_get_int_int(conf, CONF_colours, i*3+0),
                                conf_get_int_int(conf, CONF_colours, i*3+1),
                                conf_get_int_int(conf, CONF_colours, i*3+2));
        }
    } else if (event == EVENT_CALLBACK) {
        if (ctrl == cd->button) {
            int i = dlg_listbox_index(cd->listbox, dlg);
            /*
             * Collect the results of the colour selector. Will
             * return nonzero on success, or zero if the colour
             * selector did nothing (user hit Cancel, for example).
             */
            if (dlg_coloursel_results(ctrl, dlg, &r, &g, &b)) {
                conf_set_int_int(conf, CONF_colours, i*3+0, r);
                conf_set_int_int(conf, CONF_colours, i*3+1, g);
                conf_set_int_int(conf, CONF_colours, i*3+2, b);
                clear = false;
                update = true;
            }
        }
    }

    if (update) {
        if (clear) {
            dlg_editbox_set(cd->redit, dlg, "");
            dlg_editbox_set(cd->gedit, dlg, "");
            dlg_editbox_set(cd->bedit, dlg, "");
        } else {
            char buf[40];
            sprintf(buf, "%d", r); dlg_editbox_set(cd->redit, dlg, buf);
            sprintf(buf, "%d", g); dlg_editbox_set(cd->gedit, dlg, buf);
            sprintf(buf, "%d", b); dlg_editbox_set(cd->bedit, dlg, buf);
        }
    }
}

struct ttymodes_data {
    dlgcontrol *valradio, *valbox, *setbutton, *listbox;
};

static void ttymodes_handler(dlgcontrol *ctrl, dlgparam *dlg,
                             void *data, int event)
{
    Conf *conf = (Conf *)data;
    struct ttymodes_data *td =
        (struct ttymodes_data *)ctrl->context.p;

    if (event == EVENT_REFRESH) {
        if (ctrl == td->listbox) {
            char *key, *val;
            dlg_update_start(ctrl, dlg);
            dlg_listbox_clear(ctrl, dlg);
            for (val = conf_get_str_strs(conf, CONF_ttymodes, NULL, &key);
                 val != NULL;
                 val = conf_get_str_strs(conf, CONF_ttymodes, key, &key)) {
                char *disp = dupprintf("%s\t%s", key,
                                       (val[0] == 'A') ? "(auto)" :
                                       ((val[0] == 'N') ? "(don't send)"
                                                        : val+1));
                dlg_listbox_add(ctrl, dlg, disp);
                sfree(disp);
            }
            dlg_update_done(ctrl, dlg);
        } else if (ctrl == td->valradio) {
            dlg_radiobutton_set(ctrl, dlg, 0);
        }
    } else if (event == EVENT_SELCHANGE) {
        if (ctrl == td->listbox) {
            int ind = dlg_listbox_index(td->listbox, dlg);
            char *val;
            if (ind < 0) {
                return; /* no item selected */
            }
            val = conf_get_str_str(conf, CONF_ttymodes,
                                   conf_get_str_nthstrkey(conf, CONF_ttymodes,
                                                          ind));
            assert(val != NULL);
            /* Do this first to defuse side-effects on radio buttons: */
            dlg_editbox_set(td->valbox, dlg, val+1);
            dlg_radiobutton_set(td->valradio, dlg,
                                val[0] == 'A' ? 0 : (val[0] == 'N' ? 1 : 2));
        }
    } else if (event == EVENT_VALCHANGE) {
        if (ctrl == td->valbox) {
            /* If they're editing the text box, we assume they want its
             * value to be used. */
            dlg_radiobutton_set(td->valradio, dlg, 2);
        }
    } else if (event == EVENT_ACTION) {
        if (ctrl == td->setbutton) {
            int ind = dlg_listbox_index(td->listbox, dlg);
            const char *key;
            char *str, *val;
            char type;

            {
                const char types[] = {'A', 'N', 'V'};
                int button = dlg_radiobutton_get(td->valradio, dlg);
                assert(button >= 0 && button < lenof(types));
                type = types[button];
            }

            /* Construct new entry */
            if (ind >= 0) {
                key = conf_get_str_nthstrkey(conf, CONF_ttymodes, ind);
                str = (type == 'V' ? dlg_editbox_get(td->valbox, dlg)
                                   : dupstr(""));
                val = dupprintf("%c%s", type, str);
                sfree(str);
                conf_set_str_str(conf, CONF_ttymodes, key, val);
                sfree(val);
                dlg_refresh(td->listbox, dlg);
                dlg_listbox_select(td->listbox, dlg, ind);
            } else {
                /* Not a multisel listbox, so this means nothing selected */
                dlg_beep(dlg);
            }
        }
    }
}

struct environ_data {
    dlgcontrol *varbox, *valbox, *addbutton, *rembutton, *listbox;
};

static void environ_handler(dlgcontrol *ctrl, dlgparam *dlg,
                            void *data, int event)
{
    Conf *conf = (Conf *)data;
    struct environ_data *ed =
        (struct environ_data *)ctrl->context.p;

    if (event == EVENT_REFRESH) {
        if (ctrl == ed->listbox) {
            char *key, *val;
            dlg_update_start(ctrl, dlg);
            dlg_listbox_clear(ctrl, dlg);
            for (val = conf_get_str_strs(conf, CONF_environmt, NULL, &key);
                 val != NULL;
                 val = conf_get_str_strs(conf, CONF_environmt, key, &key)) {
                char *p = dupprintf("%s\t%s", key, val);
                dlg_listbox_add(ctrl, dlg, p);
                sfree(p);
            }
            dlg_update_done(ctrl, dlg);
        }
    } else if (event == EVENT_ACTION) {
        if (ctrl == ed->addbutton) {
            char *key, *val, *str;
            key = dlg_editbox_get(ed->varbox, dlg);
            if (!*key) {
                sfree(key);
                dlg_beep(dlg);
                return;
            }
            val = dlg_editbox_get(ed->valbox, dlg);
            if (!*val) {
                sfree(key);
                sfree(val);
                dlg_beep(dlg);
                return;
            }
            conf_set_str_str(conf, CONF_environmt, key, val);
            str = dupcat(key, "\t", val);
            dlg_editbox_set(ed->varbox, dlg, "");
            dlg_editbox_set(ed->valbox, dlg, "");
            sfree(str);
            sfree(key);
            sfree(val);
            dlg_refresh(ed->listbox, dlg);
        } else if (ctrl == ed->rembutton) {
            int i = dlg_listbox_index(ed->listbox, dlg);
            if (i < 0) {
                dlg_beep(dlg);
            } else {
                char *key, *val;

                key = conf_get_str_nthstrkey(conf, CONF_environmt, i);
                if (key) {
                    /* Populate controls with the entry we're about to delete
                     * for ease of editing */
                    val = conf_get_str_str(conf, CONF_environmt, key);
                    dlg_editbox_set(ed->varbox, dlg, key);
                    dlg_editbox_set(ed->valbox, dlg, val);
                    /* And delete it */
                    conf_del_str_str(conf, CONF_environmt, key);
                }
            }
            dlg_refresh(ed->listbox, dlg);
        }
    }
}

struct portfwd_data {
    dlgcontrol *addbutton, *rembutton, *listbox;
    dlgcontrol *sourcebox, *destbox, *direction;
#ifndef NO_IPV6
    dlgcontrol *addressfamily;
#endif
};

static void portfwd_handler(dlgcontrol *ctrl, dlgparam *dlg,
                            void *data, int event)
{
    Conf *conf = (Conf *)data;
    struct portfwd_data *pfd =
        (struct portfwd_data *)ctrl->context.p;

    if (event == EVENT_REFRESH) {
        if (ctrl == pfd->listbox) {
            char *key, *val;
            dlg_update_start(ctrl, dlg);
            dlg_listbox_clear(ctrl, dlg);
            for (val = conf_get_str_strs(conf, CONF_portfwd, NULL, &key);
                 val != NULL;
                 val = conf_get_str_strs(conf, CONF_portfwd, key, &key)) {
                char *p;
                if (!strcmp(val, "D")) {
                    char *L;
                    /*
                     * A dynamic forwarding is stored as L12345=D or
                     * 6L12345=D (since it's mutually exclusive with
                     * L12345=anything else), but displayed as D12345
                     * to match the fiction that 'Local', 'Remote' and
                     * 'Dynamic' are three distinct modes and also to
                     * align with OpenSSH's command line option syntax
                     * that people will already be used to. So, for
                     * display purposes, find the L in the key string
                     * and turn it into a D.
                     */
                    p = dupprintf("%s\t", key);
                    L = strchr(p, 'L');
                    if (L) *L = 'D';
                } else
                    p = dupprintf("%s\t%s", key, val);
                dlg_listbox_add(ctrl, dlg, p);
                sfree(p);
            }
            dlg_update_done(ctrl, dlg);
        } else if (ctrl == pfd->direction) {
            /*
             * Default is Local.
             */
            dlg_radiobutton_set(ctrl, dlg, 0);
#ifndef NO_IPV6
        } else if (ctrl == pfd->addressfamily) {
            dlg_radiobutton_set(ctrl, dlg, 0);
#endif
        }
    } else if (event == EVENT_ACTION) {
        if (ctrl == pfd->addbutton) {
            const char *family, *type;
            char *src, *key, *val;
            int whichbutton;

#ifndef NO_IPV6
            whichbutton = dlg_radiobutton_get(pfd->addressfamily, dlg);
            if (whichbutton == 1)
                family = "4";
            else if (whichbutton == 2)
                family = "6";
            else
#endif
                family = "";

            whichbutton = dlg_radiobutton_get(pfd->direction, dlg);
            if (whichbutton == 0)
                type = "L";
            else if (whichbutton == 1)
                type = "R";
            else
                type = "D";

            src = dlg_editbox_get(pfd->sourcebox, dlg);
            if (!*src) {
                dlg_error_msg(dlg, "You need to specify a source port number");
                sfree(src);
                return;
            }
            if (*type != 'D') {
                val = dlg_editbox_get(pfd->destbox, dlg);
                if (!*val || !host_strchr(val, ':')) {
                    dlg_error_msg(dlg,
                                  "You need to specify a destination address\n"
                                  "in the form \"host.name:port\"");
                    sfree(src);
                    sfree(val);
                    return;
                }
            } else {
                type = "L";
                val = dupstr("D");     /* special case */
            }

            key = dupcat(family, type, src);
            sfree(src);

            if (conf_get_str_str_opt(conf, CONF_portfwd, key)) {
                dlg_error_msg(dlg, "Specified forwarding already exists");
            } else {
                conf_set_str_str(conf, CONF_portfwd, key, val);
            }

            sfree(key);
            sfree(val);
            dlg_refresh(pfd->listbox, dlg);
        } else if (ctrl == pfd->rembutton) {
            int i = dlg_listbox_index(pfd->listbox, dlg);
            if (i < 0) {
                dlg_beep(dlg);
            } else {
                char *key, *p;
                const char *val;

                key = conf_get_str_nthstrkey(conf, CONF_portfwd, i);
                if (key) {
                    static const char *const afs = "A46";
                    static const char *const dirs = "LRD";
                    const char *afp;
                    int dir;
#ifndef NO_IPV6
                    int idx;
#endif

                    /* Populate controls with the entry we're about to delete
                     * for ease of editing */
                    p = key;

                    afp = strchr(afs, *p);
#ifndef NO_IPV6
                    idx = afp ? afp-afs : 0;
#endif
                    if (afp)
                        p++;
#ifndef NO_IPV6
                    dlg_radiobutton_set(pfd->addressfamily, dlg, idx);
#endif

                    dir = *p;

                    val = conf_get_str_str(conf, CONF_portfwd, key);
                    if (!strcmp(val, "D")) {
                        dir = 'D';
                        val = "";
                    }

                    dlg_radiobutton_set(pfd->direction, dlg,
                                        strchr(dirs, dir) - dirs);
                    p++;

                    dlg_editbox_set(pfd->sourcebox, dlg, p);
                    dlg_editbox_set(pfd->destbox, dlg, val);
                    /* And delete it */
                    conf_del_str_str(conf, CONF_portfwd, key);
                }
            }
            dlg_refresh(pfd->listbox, dlg);
        }
    }
}

struct manual_hostkey_data {
    dlgcontrol *addbutton, *rembutton, *listbox, *keybox;
};

static void manual_hostkey_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                   void *data, int event)
{
    Conf *conf = (Conf *)data;
    struct manual_hostkey_data *mh =
        (struct manual_hostkey_data *)ctrl->context.p;

    if (event == EVENT_REFRESH) {
        if (ctrl == mh->listbox) {
            char *key, *val;
            dlg_update_start(ctrl, dlg);
            dlg_listbox_clear(ctrl, dlg);
            for (val = conf_get_str_strs(conf, CONF_ssh_manual_hostkeys,
                                         NULL, &key);
                 val != NULL;
                 val = conf_get_str_strs(conf, CONF_ssh_manual_hostkeys,
                                         key, &key)) {
                dlg_listbox_add(ctrl, dlg, key);
            }
            dlg_update_done(ctrl, dlg);
        }
    } else if (event == EVENT_ACTION) {
        if (ctrl == mh->addbutton) {
            char *key;

            key = dlg_editbox_get(mh->keybox, dlg);
            if (!*key) {
                dlg_error_msg(dlg, "You need to specify a host key or "
                              "fingerprint");
                sfree(key);
                return;
            }

            if (!validate_manual_hostkey(key)) {
                dlg_error_msg(dlg, "Host key is not in a valid format");
            } else if (conf_get_str_str_opt(conf, CONF_ssh_manual_hostkeys,
                                            key)) {
                dlg_error_msg(dlg, "Specified host key is already listed");
            } else {
                conf_set_str_str(conf, CONF_ssh_manual_hostkeys, key, "");
            }

            sfree(key);
            dlg_refresh(mh->listbox, dlg);
        } else if (ctrl == mh->rembutton) {
            int i = dlg_listbox_index(mh->listbox, dlg);
            if (i < 0) {
                dlg_beep(dlg);
            } else {
                char *key;

                key = conf_get_str_nthstrkey(conf, CONF_ssh_manual_hostkeys, i);
                if (key) {
                    dlg_editbox_set(mh->keybox, dlg, key);
                    /* And delete it */
                    conf_del_str_str(conf, CONF_ssh_manual_hostkeys, key);
                }
            }
            dlg_refresh(mh->listbox, dlg);
        }
    }
}

static void clipboard_selector_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                       void *data, int event)
{
    Conf *conf = (Conf *)data;
    int setting = ctrl->context.i;
#ifdef NAMED_CLIPBOARDS
    int strsetting = ctrl->context2.i;
#endif

    static const struct {
        const char *name;
        int id;
    } options[] = {
        {"No action", CLIPUI_NONE},
        {CLIPNAME_IMPLICIT, CLIPUI_IMPLICIT},
        {CLIPNAME_EXPLICIT, CLIPUI_EXPLICIT},
    };

    if (event == EVENT_REFRESH) {
        int i, val = conf_get_int(conf, setting);

        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);

#ifdef NAMED_CLIPBOARDS
        for (i = 0; i < lenof(options); i++)
            dlg_listbox_add(ctrl, dlg, options[i].name);
        if (val == CLIPUI_CUSTOM) {
            const char *sval = conf_get_str(conf, strsetting);
            for (i = 0; i < lenof(options); i++)
                if (!strcmp(sval, options[i].name))
                    break;             /* needs escaping */
            if (i < lenof(options) || sval[0] == '=') {
                char *escaped = dupcat("=", sval);
                dlg_editbox_set(ctrl, dlg, escaped);
                sfree(escaped);
            } else {
                dlg_editbox_set(ctrl, dlg, sval);
            }
        } else {
            dlg_editbox_set(ctrl, dlg, options[0].name); /* fallback */
            for (i = 0; i < lenof(options); i++)
                if (val == options[i].id)
                    dlg_editbox_set(ctrl, dlg, options[i].name);
        }
#else
        for (i = 0; i < lenof(options); i++)
            dlg_listbox_addwithid(ctrl, dlg, options[i].name, options[i].id);
        dlg_listbox_select(ctrl, dlg, 0); /* fallback */
        for (i = 0; i < lenof(options); i++)
            if (val == options[i].id)
                dlg_listbox_select(ctrl, dlg, i);
#endif
        dlg_update_done(ctrl, dlg);
    } else if (event == EVENT_SELCHANGE
#ifdef NAMED_CLIPBOARDS
               || event == EVENT_VALCHANGE
#endif
        ) {
#ifdef NAMED_CLIPBOARDS
        char *sval = dlg_editbox_get(ctrl, dlg);
        int i;

        for (i = 0; i < lenof(options); i++)
            if (!strcmp(sval, options[i].name)) {
                conf_set_int(conf, setting, options[i].id);
                conf_set_str(conf, strsetting, "");
                break;
            }
        if (i == lenof(options)) {
            conf_set_int(conf, setting, CLIPUI_CUSTOM);
            if (sval[0] == '=')
                sval++;
            conf_set_str(conf, strsetting, sval);
        }

        sfree(sval);
#else
        int index = dlg_listbox_index(ctrl, dlg);
        if (index >= 0) {
            int val = dlg_listbox_getid(ctrl, dlg, index);
            conf_set_int(conf, setting, val);
        }
#endif
    }
}

static void clipboard_control(struct controlset *s, const char *label,
                              char shortcut, int percentage, HelpCtx helpctx,
                              int setting, int strsetting)
{
#ifdef NAMED_CLIPBOARDS
    ctrl_combobox(s, label, shortcut, percentage, helpctx,
                  clipboard_selector_handler, I(setting), I(strsetting));
#else
    /* strsetting isn't needed in this case */
    ctrl_droplist(s, label, shortcut, percentage, helpctx,
                  clipboard_selector_handler, I(setting));
#endif
}

static void serial_parity_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                  void *data, int event)
{
    static const struct {
        const char *name;
        int val;
    } parities[] = {
        {"None", SER_PAR_NONE},
        {"Odd", SER_PAR_ODD},
        {"Even", SER_PAR_EVEN},
        {"Mark", SER_PAR_MARK},
        {"Space", SER_PAR_SPACE},
    };
    int mask = ctrl->context.i;
    int i, j;
    Conf *conf = (Conf *)data;

    if (event == EVENT_REFRESH) {
        /* Fetching this once at the start of the function ensures we
         * remember what the right value is supposed to be when
         * operations below cause reentrant calls to this function. */
        int oldparity = conf_get_int(conf, CONF_serparity);

        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);
        for (i = 0; i < lenof(parities); i++)  {
            if (mask & (1 << parities[i].val))
                dlg_listbox_addwithid(ctrl, dlg, parities[i].name,
                                      parities[i].val);
        }
        for (i = j = 0; i < lenof(parities); i++) {
            if (mask & (1 << parities[i].val)) {
                if (oldparity == parities[i].val) {
                    dlg_listbox_select(ctrl, dlg, j);
                    break;
                }
                j++;
            }
        }
        if (i == lenof(parities)) {    /* an unsupported setting was chosen */
            dlg_listbox_select(ctrl, dlg, 0);
            oldparity = SER_PAR_NONE;
        }
        dlg_update_done(ctrl, dlg);
        conf_set_int(conf, CONF_serparity, oldparity);    /* restore */
    } else if (event == EVENT_SELCHANGE) {
        int i = dlg_listbox_index(ctrl, dlg);
        if (i < 0)
            i = SER_PAR_NONE;
        else
            i = dlg_listbox_getid(ctrl, dlg, i);
        conf_set_int(conf, CONF_serparity, i);
    }
}

static void serial_flow_handler(dlgcontrol *ctrl, dlgparam *dlg,
                                void *data, int event)
{
    static const struct {
        const char *name;
        int val;
    } flows[] = {
        {"None", SER_FLOW_NONE},
        {"XON/XOFF", SER_FLOW_XONXOFF},
        {"RTS/CTS", SER_FLOW_RTSCTS},
        {"DSR/DTR", SER_FLOW_DSRDTR},
    };
    int mask = ctrl->context.i;
    int i, j;
    Conf *conf = (Conf *)data;

    if (event == EVENT_REFRESH) {
        /* Fetching this once at the start of the function ensures we
         * remember what the right value is supposed to be when
         * operations below cause reentrant calls to this function. */
        int oldflow = conf_get_int(conf, CONF_serflow);

        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);
        for (i = 0; i < lenof(flows); i++)  {
            if (mask & (1 << flows[i].val))
                dlg_listbox_addwithid(ctrl, dlg, flows[i].name, flows[i].val);
        }
        for (i = j = 0; i < lenof(flows); i++) {
            if (mask & (1 << flows[i].val)) {
                if (oldflow == flows[i].val) {
                    dlg_listbox_select(ctrl, dlg, j);
                    break;
                }
                j++;
            }
        }
        if (i == lenof(flows)) {       /* an unsupported setting was chosen */
            dlg_listbox_select(ctrl, dlg, 0);
            oldflow = SER_FLOW_NONE;
        }
        dlg_update_done(ctrl, dlg);
        conf_set_int(conf, CONF_serflow, oldflow);/* restore */
    } else if (event == EVENT_SELCHANGE) {
        int i = dlg_listbox_index(ctrl, dlg);
        if (i < 0)
            i = SER_FLOW_NONE;
        else
            i = dlg_listbox_getid(ctrl, dlg, i);
        conf_set_int(conf, CONF_serflow, i);
    }
}

void proxy_type_handler(dlgcontrol *ctrl, dlgparam *dlg,
                        void *data, int event)
{
    Conf *conf = (Conf *)data;
    if (event == EVENT_REFRESH) {
        /*
         * We must fetch the previously configured value from the Conf
         * before we start modifying the drop-down list, otherwise the
         * spurious SELCHANGE we trigger in the process will overwrite
         * the value we wanted to keep.
         */
        int proxy_type = conf_get_int(conf, CONF_proxy_type);

        dlg_update_start(ctrl, dlg);
        dlg_listbox_clear(ctrl, dlg);

        int index_to_select = 0, current_index = 0;

#define ADD(id, title) do {                                     \
            dlg_listbox_addwithid(ctrl, dlg, title, id);        \
            if (id == proxy_type)                               \
                index_to_select = current_index;                \
            current_index++;                                    \
        } while (0)

        ADD(PROXY_NONE, "None");
        ADD(PROXY_SOCKS5, "SOCKS 5");
        ADD(PROXY_SOCKS4, "SOCKS 4");
        ADD(PROXY_HTTP, "HTTP CONNECT");
        if (ssh_proxy_supported) {
            ADD(PROXY_SSH_TCPIP, "SSH to proxy and use port forwarding");
            ADD(PROXY_SSH_EXEC, "SSH to proxy and execute a command");
            ADD(PROXY_SSH_SUBSYSTEM, "SSH to proxy and invoke a subsystem");
        }
        if (ctrl->context.i & PROXY_UI_FLAG_LOCAL) {
            ADD(PROXY_CMD, "Local (run a subprogram to connect)");
        }
        ADD(PROXY_TELNET, "'Telnet' (send an ad-hoc command)");

#undef ADD

        dlg_listbox_select(ctrl, dlg, index_to_select);

        dlg_update_done(ctrl, dlg);
    } else if (event == EVENT_SELCHANGE) {
        int i = dlg_listbox_index(ctrl, dlg);
        if (i < 0)
            i = AUTO;
        else
            i = dlg_listbox_getid(ctrl, dlg, i);
        conf_set_int(conf, CONF_proxy_type, i);
    }
}

static void host_ca_button_handler(dlgcontrol *ctrl, dlgparam *dp,
                                   void *data, int event)
{
    if (event == EVENT_ACTION)
        show_ca_config_box(dp);
}

void setup_config_box(struct controlbox *b, bool midsession,
                      int protocol, int protcfginfo)
{
    const struct BackendVtable *backvt;
    struct controlset *s;
    struct sessionsaver_data *ssd;
    struct charclass_data *ccd;
    struct colour_data *cd;
    struct ttymodes_data *td;
    struct environ_data *ed;
    struct portfwd_data *pfd;
    struct manual_hostkey_data *mh;
    dlgcontrol *c;
    bool resize_forbidden = false;
    char *str;

    ssd = (struct sessionsaver_data *)
        ctrl_alloc_with_free(b, sizeof(struct sessionsaver_data),
                             sessionsaver_data_free);
    memset(ssd, 0, sizeof(*ssd));
    ssd->savedsession = dupstr("");
    ssd->midsession = midsession;

    /*
     * The standard panel that appears at the bottom of all panels:
     * Open, Cancel, Apply etc.
     */
    s = ctrl_getset(b, "", "", "");
    ctrl_columns(s, 5, 20, 20, 20, 20, 20);
    ssd->okbutton = ctrl_pushbutton(s,
                                    (midsession ? "Apply" : "Open"),
                                    (char)(midsession ? 'a' : 'o'),
                                    HELPCTX(no_help),
                                    sessionsaver_handler, P(ssd));
    ssd->okbutton->button.isdefault = true;
    ssd->okbutton->column = 3;
    ssd->cancelbutton = ctrl_pushbutton(s, "Cancel", 'c', HELPCTX(no_help),
                                        sessionsaver_handler, P(ssd));
    ssd->cancelbutton->button.iscancel = true;
    ssd->cancelbutton->column = 4;
    /* We carefully don't close the 5-column part, so that platform-
     * specific add-ons can put extra buttons alongside Open and Cancel. */

    /*
     * The Session panel.
     */
    str = dupprintf("Basic options for your %s session", appname);
    ctrl_settitle(b, "Session", str);
    sfree(str);

    if (!midsession) {
        struct hostport *hp = (struct hostport *)
            ctrl_alloc(b, sizeof(struct hostport));
        memset(hp, 0, sizeof(*hp));

        s = ctrl_getset(b, "Session", "hostport",
                        "Specify the destination you want to connect to");
        ctrl_columns(s, 2, 75, 25);
        c = ctrl_editbox(s, HOST_BOX_TITLE, 'n', 100,
                         HELPCTX(session_hostname),
                         config_host_handler, I(0), I(0));
        c->column = 0;
        hp->host = c;
        c = ctrl_editbox(s, PORT_BOX_TITLE, 'p', 100,
                         HELPCTX(session_hostname),
                         config_port_handler, I(0), I(0));
        c->column = 1;
        hp->port = c;

        ctrl_columns(s, 1, 100);
        c = ctrl_text(s, "Connection type:", HELPCTX(session_hostname));
        ctrl_columns(s, 2, 62, 38);
        c = ctrl_radiobuttons(s, NULL, NO_SHORTCUT, 3,
                              HELPCTX(session_hostname),
                              config_protocols_handler, P(hp));
        c->column = 0;
        hp->protradio = c;
        c->radio.buttons = sresize(c->radio.buttons, PROTOCOL_LIMIT, char *);
        c->radio.shortcuts = sresize(c->radio.shortcuts, PROTOCOL_LIMIT, char);
        c->radio.buttondata = sresize(c->radio.buttondata, PROTOCOL_LIMIT,
                                      intorptr);
        assert(c->radio.nbuttons == 0);
        /* UI design assumes there exists at least one 'real' radio button */
        assert(n_ui_backends > 0 && n_ui_backends < PROTOCOL_LIMIT);
        for (size_t i = 0; i < n_ui_backends; i++) {
            assert(backends[i]);
            c->radio.buttons[c->radio.nbuttons] =
                dupstr(backends[i]->displayname_tc);
            c->radio.shortcuts[c->radio.nbuttons] =
                (backends[i]->protocol == PROT_SSH ? 's' :
                 backends[i]->protocol == PROT_SERIAL ? 'r' :
                 backends[i]->protocol == PROT_RAW ? 'w' :  /* FIXME unused */
                 NO_SHORTCUT);
            c->radio.buttondata[c->radio.nbuttons] =
                I(backends[i]->protocol);
            c->radio.nbuttons++;
        }
        /* UI design assumes there exists at least one droplist entry */
        assert(backends[c->radio.nbuttons]);

        c->radio.buttons[c->radio.nbuttons] = dupstr("Other:");
        c->radio.shortcuts[c->radio.nbuttons] = 't';
        c->radio.buttondata[c->radio.nbuttons] = I(-1);
        c->radio.nbuttons++;

        c = ctrl_droplist(s, NULL, NO_SHORTCUT, 100,
                          HELPCTX(session_hostname),
                          config_protocols_handler, P(hp));
        hp->protlist = c;
        /* droplist is populated in config_protocols_handler */
        c->column = 1;

        /* Vertically centre the two protocol controls w.r.t. each other */
        hp->protlist->align_next_to = hp->protradio;

        ctrl_columns(s, 1, 100);
    }

    /*
     * The Load/Save panel is available even in mid-session.
     */
    s = ctrl_getset(b, "Session", "savedsessions",
                    midsession ? "Save the current session settings" :
                    "Load, save or delete a stored session");
    ctrl_columns(s, 2, 75, 25);
    get_sesslist(&ssd->sesslist, true);
    ssd->editbox = ctrl_editbox(s, "Saved Sessions", 'e', 100,
                                HELPCTX(session_saved),
                                sessionsaver_handler, P(ssd), P(NULL));
    ssd->editbox->column = 0;
    /* Reset columns so that the buttons are alongside the list, rather
     * than alongside that edit box. */
    ctrl_columns(s, 1, 100);
    ctrl_columns(s, 2, 75, 25);
    ssd->listbox = ctrl_listbox(s, NULL, NO_SHORTCUT,
                                HELPCTX(session_saved),
                                sessionsaver_handler, P(ssd));
    ssd->listbox->column = 0;
    ssd->listbox->listbox.height = 7;
    if (!midsession) {
        ssd->loadbutton = ctrl_pushbutton(s, "Load", 'l',
                                          HELPCTX(session_saved),
                                          sessionsaver_handler, P(ssd));
        ssd->loadbutton->column = 1;
    } else {
        /* We can't offer the Load button mid-session, as it would allow the
         * user to load and subsequently save settings they can't see. (And
         * also change otherwise immutable settings underfoot; that probably
         * shouldn't be a problem, but.) */
        ssd->loadbutton = NULL;
    }
    /* "Save" button is permitted mid-session. */
    ssd->savebutton = ctrl_pushbutton(s, "Save", 'v',
                                      HELPCTX(session_saved),
                                      sessionsaver_handler, P(ssd));
    ssd->savebutton->column = 1;
    if (!midsession) {
        ssd->delbutton = ctrl_pushbutton(s, "Delete", 'd',
                                         HELPCTX(session_saved),
                                         sessionsaver_handler, P(ssd));
        ssd->delbutton->column = 1;
    } else {
        /* Disable the Delete button mid-session too, for UI consistency. */
        ssd->delbutton = NULL;
    }
    ctrl_columns(s, 1, 100);

    s = ctrl_getset(b, "Session", "otheropts", NULL);
    ctrl_radiobuttons(s, "Close window on exit:", 'x', 4,
                      HELPCTX(session_coe),
                      conf_radiobutton_handler,
                      I(CONF_close_on_exit),
                      "Always", I(FORCE_ON),
                      "Never", I(FORCE_OFF),
                      "Only on clean exit", I(AUTO));

    /*
     * The Session/Logging panel.
     */
    ctrl_settitle(b, "Session/Logging", "Options controlling session logging");

    s = ctrl_getset(b, "Session/Logging", "main", NULL);
    /*
     * The logging buttons change depending on whether SSH packet
     * logging can sensibly be available.
     */
    {
        const char *sshlogname, *sshrawlogname;
        if ((midsession && protocol == PROT_SSH) ||
            (!midsession && backend_vt_from_proto(PROT_SSH))) {
            sshlogname = "SSH packets";
            sshrawlogname = "SSH packets and raw data";
        } else {
            sshlogname = NULL;         /* this will disable both buttons */
            sshrawlogname = NULL;      /* this will just placate optimisers */
        }
        ctrl_radiobuttons(s, "Session logging:", NO_SHORTCUT, 2,
                          HELPCTX(logging_main),
                          loggingbuttons_handler,
                          I(CONF_logtype),
                          "None", 't', I(LGTYP_NONE),
                          "Printable output", 'p', I(LGTYP_ASCII),
                          "All session output", 'l', I(LGTYP_DEBUG),
                          sshlogname, 's', I(LGTYP_PACKETS),
                          sshrawlogname, 'r', I(LGTYP_SSHRAW));
    }
    ctrl_filesel(s, "Log file name:", 'f',
                 FILTER_ALL_FILES, true, "Select session log file name",
                 HELPCTX(logging_filename),
                 conf_filesel_handler, I(CONF_logfilename));
    ctrl_text(s, "(Log file name can contain &Y, &M, &D for date,"
              " &T for time, &H for host name, and &P for port number)",
              HELPCTX(logging_filename));
    ctrl_radiobuttons(s, "What to do if the log file already exists:", 'e', 1,
                      HELPCTX(logging_exists),
                      conf_radiobutton_handler, I(CONF_logxfovr),
                      "Always overwrite it", I(LGXF_OVR),
                      "Always append to the end of it", I(LGXF_APN),
                      "Ask the user every time", I(LGXF_ASK));
    ctrl_checkbox(s, "Flush log file frequently", 'u',
                  HELPCTX(logging_flush),
                  conf_checkbox_handler, I(CONF_logflush));
    ctrl_checkbox(s, "Include header", 'i',
                  HELPCTX(logging_header),
                  conf_checkbox_handler, I(CONF_logheader));

    if ((midsession && protocol == PROT_SSH) ||
        (!midsession && backend_vt_from_proto(PROT_SSH))) {
        s = ctrl_getset(b, "Session/Logging", "ssh",
                        "Options specific to SSH packet logging");
        ctrl_checkbox(s, "Omit known password fields", 'k',
                      HELPCTX(logging_ssh_omit_password),
                      conf_checkbox_handler, I(CONF_logomitpass));
        ctrl_checkbox(s, "Omit session data", 'd',
                      HELPCTX(logging_ssh_omit_data),
                      conf_checkbox_handler, I(CONF_logomitdata));
    }

    /*
     * The Terminal panel.
     */
    ctrl_settitle(b, "Terminal", "Options controlling the terminal emulation");

    s = ctrl_getset(b, "Terminal", "general", "Set various terminal options");
    ctrl_checkbox(s, "Auto wrap mode initially on", 'w',
                  HELPCTX(terminal_autowrap),
                  conf_checkbox_handler, I(CONF_wrap_mode));
    ctrl_checkbox(s, "DEC Origin Mode initially on", 'd',
                  HELPCTX(terminal_decom),
                  conf_checkbox_handler, I(CONF_dec_om));
    ctrl_checkbox(s, "Implicit CR in every LF", 'r',
                  HELPCTX(terminal_lfhascr),
                  conf_checkbox_handler, I(CONF_lfhascr));
    ctrl_checkbox(s, "Implicit LF in every CR", 'f',
                  HELPCTX(terminal_crhaslf),
                  conf_checkbox_handler, I(CONF_crhaslf));
    ctrl_checkbox(s, "Use background colour to erase screen", 'e',
                  HELPCTX(terminal_bce),
                  conf_checkbox_handler, I(CONF_bce));
    ctrl_checkbox(s, "Enable blinking text", 'n',
                  HELPCTX(terminal_blink),
                  conf_checkbox_handler, I(CONF_blinktext));
    ctrl_editbox(s, "Answerback to ^E:", 's', 100,
                 HELPCTX(terminal_answerback),
                 conf_editbox_handler, I(CONF_answerback), ED_STR);

    s = ctrl_getset(b, "Terminal", "ldisc", "Line discipline options");
    ctrl_radiobuttons(s, "Local echo:", 'l', 3,
                      HELPCTX(terminal_localecho),
                      conf_radiobutton_handler,I(CONF_localecho),
                      "Auto", I(AUTO),
                      "Force on", I(FORCE_ON),
                      "Force off", I(FORCE_OFF));
    ctrl_radiobuttons(s, "Local line editing:", 't', 3,
                      HELPCTX(terminal_localedit),
                      conf_radiobutton_handler,I(CONF_localedit),
                      "Auto", I(AUTO),
                      "Force on", I(FORCE_ON),
                      "Force off", I(FORCE_OFF));

    s = ctrl_getset(b, "Terminal", "printing", "Remote-controlled printing");
    ctrl_combobox(s, "Printer to send ANSI printer output to:", 'p', 100,
                  HELPCTX(terminal_printing),
                  printerbox_handler, P(NULL), P(NULL));

    /*
     * The Terminal/Keyboard panel.
     */
    ctrl_settitle(b, "Terminal/Keyboard",
                  "Options controlling the effects of keys");

    s = ctrl_getset(b, "Terminal/Keyboard", "mappings",
                    "Change the sequences sent by:");
    ctrl_radiobuttons(s, "The Backspace key", 'b', 2,
                      HELPCTX(keyboard_backspace),
                      conf_radiobutton_bool_handler,
                      I(CONF_bksp_is_delete),
                      "Control-H", I(0), "Control-? (127)", I(1));
    ctrl_radiobuttons(s, "The Home and End keys", 'e', 2,
                      HELPCTX(keyboard_homeend),
                      conf_radiobutton_bool_handler,
                      I(CONF_rxvt_homeend),
                      "Standard", I(false), "rxvt", I(true));
    ctrl_radiobuttons(s, "The Function keys and keypad", 'f', 4,
                      HELPCTX(keyboard_funkeys),
                      conf_radiobutton_handler,
                      I(CONF_funky_type),
                      "ESC[n~", I(FUNKY_TILDE),
                      "Linux", I(FUNKY_LINUX),
                      "Xterm R6", I(FUNKY_XTERM),
                      "VT400", I(FUNKY_VT400),
                      "VT100+", I(FUNKY_VT100P),
                      "SCO", I(FUNKY_SCO),
                      "Xterm 216+", I(FUNKY_XTERM_216));
    ctrl_radiobuttons(s, "Shift/Ctrl/Alt with the arrow keys", 'w', 2,
                      HELPCTX(keyboard_sharrow),
                      conf_radiobutton_handler,
                      I(CONF_sharrow_type),
                      "Ctrl toggles app mode", I(SHARROW_APPLICATION),
                      "xterm-style bitmap", I(SHARROW_BITMAP));

    s = ctrl_getset(b, "Terminal/Keyboard", "appkeypad",
                    "Application keypad settings:");
    ctrl_radiobuttons(s, "Initial state of cursor keys:", 'r', 3,
                      HELPCTX(keyboard_appcursor),
                      conf_radiobutton_bool_handler,
                      I(CONF_app_cursor),
                      "Normal", I(0), "Application", I(1));
    ctrl_radiobuttons(s, "Initial state of numeric keypad:", 'n', 3,
                      HELPCTX(keyboard_appkeypad),
                      numeric_keypad_handler, P(NULL),
                      "Normal", I(0), "Application", I(1), "NetHack", I(2));

    /*
     * The Terminal/Bell panel.
     */
    ctrl_settitle(b, "Terminal/Bell",
                  "Options controlling the terminal bell");

    s = ctrl_getset(b, "Terminal/Bell", "style", "Set the style of bell");
    ctrl_radiobuttons(s, "Action to happen when a bell occurs:", 'b', 1,
                      HELPCTX(bell_style),
                      conf_radiobutton_handler, I(CONF_beep),
                      "None (bell disabled)", I(BELL_DISABLED),
                      "Make default system alert sound", I(BELL_DEFAULT),
                      "Visual bell (flash window)", I(BELL_VISUAL));

    s = ctrl_getset(b, "Terminal/Bell", "overload",
                    "Control the bell overload behaviour");
    ctrl_checkbox(s, "Bell is temporarily disabled when over-used", 'd',
                  HELPCTX(bell_overload),
                  conf_checkbox_handler, I(CONF_bellovl));
    ctrl_editbox(s, "Over-use means this many bells...", 'm', 20,
                 HELPCTX(bell_overload),
                 conf_editbox_handler, I(CONF_bellovl_n), ED_INT);

    static const struct conf_editbox_handler_type conf_editbox_tickspersec = {
        .type = EDIT_FIXEDPOINT, .denominator = TICKSPERSEC};

    ctrl_editbox(s, "... in this many seconds", 't', 20,
                 HELPCTX(bell_overload),
                 conf_editbox_handler, I(CONF_bellovl_t),
                 CP(&conf_editbox_tickspersec));
    ctrl_text(s, "The bell is re-enabled after a few seconds of silence.",
              HELPCTX(bell_overload));
    ctrl_editbox(s, "Seconds of silence required", 's', 20,
                 HELPCTX(bell_overload),
                 conf_editbox_handler, I(CONF_bellovl_s),
                 CP(&conf_editbox_tickspersec));

    /*
     * The Terminal/Features panel.
     */
    ctrl_settitle(b, "Terminal/Features",
                  "Enabling and disabling advanced terminal features");

    s = ctrl_getset(b, "Terminal/Features", "main", NULL);
    ctrl_checkbox(s, "Disable application cursor keys mode", 'u',
                  HELPCTX(features_application),
                  conf_checkbox_handler, I(CONF_no_applic_c));
    ctrl_checkbox(s, "Disable application keypad mode", 'k',
                  HELPCTX(features_application),
                  conf_checkbox_handler, I(CONF_no_applic_k));
    ctrl_checkbox(s, "Disable xterm-style mouse reporting", 'x',
                  HELPCTX(features_mouse),
                  conf_checkbox_handler, I(CONF_no_mouse_rep));
    ctrl_checkbox(s, "Disable remote-controlled terminal resizing", 's',
                  HELPCTX(features_resize),
                  conf_checkbox_handler,
                  I(CONF_no_remote_resize));
    ctrl_checkbox(s, "Disable switching to alternate terminal screen", 'w',
                  HELPCTX(features_altscreen),
                  conf_checkbox_handler, I(CONF_no_alt_screen));
    ctrl_checkbox(s, "Disable remote-controlled window title changing", 't',
                  HELPCTX(features_retitle),
                  conf_checkbox_handler,
                  I(CONF_no_remote_wintitle));
    ctrl_radiobuttons(s, "Response to remote title query (SECURITY):", 'q', 3,
                      HELPCTX(features_qtitle),
                      conf_radiobutton_handler,
                      I(CONF_remote_qtitle_action),
                      "None", I(TITLE_NONE),
                      "Empty string", I(TITLE_EMPTY),
                      "Window title", I(TITLE_REAL));
    ctrl_checkbox(s, "Disable remote-controlled clearing of scrollback", 'e',
                  HELPCTX(features_clearscroll),
                  conf_checkbox_handler,
                  I(CONF_no_remote_clearscroll));
    ctrl_checkbox(s, "Disable destructive backspace on server sending ^?",'b',
                  HELPCTX(features_dbackspace),
                  conf_checkbox_handler, I(CONF_no_dbackspace));
    ctrl_checkbox(s, "Disable remote-controlled character set configuration",
                  'r', HELPCTX(features_charset), conf_checkbox_handler,
                  I(CONF_no_remote_charset));
    ctrl_checkbox(s, "Disable Arabic text shaping",
                  'l', HELPCTX(features_arabicshaping), conf_checkbox_handler,
                  I(CONF_no_arabicshaping));
    ctrl_checkbox(s, "Disable bidirectional text display",
                  'd', HELPCTX(features_bidi), conf_checkbox_handler,
                  I(CONF_no_bidi));
    ctrl_checkbox(s, "Disable bracketed paste mode",
                  'p', HELPCTX(features_bracketed_paste), conf_checkbox_handler,
                  I(CONF_no_bracketed_paste));

    /*
     * The Window panel.
     */
    str = dupprintf("Options controlling %s's window", appname);
    ctrl_settitle(b, "Window", str);
    sfree(str);

    backvt = backend_vt_from_proto(protocol);
    if (backvt)
        resize_forbidden = (backvt->flags & BACKEND_RESIZE_FORBIDDEN);

    if (!resize_forbidden || !midsession) {
        s = ctrl_getset(b, "Window", "size", "Set the size of the window");
        ctrl_columns(s, 2, 50, 50);
        c = ctrl_editbox(s, "Columns", 'm', 100,
                         HELPCTX(window_size),
                         conf_editbox_handler, I(CONF_width), ED_INT);
        c->column = 0;
        c = ctrl_editbox(s, "Rows", 'r', 100,
                         HELPCTX(window_size),
                         conf_editbox_handler, I(CONF_height),ED_INT);
        c->column = 1;
        ctrl_columns(s, 1, 100);
    }

    s = ctrl_getset(b, "Window", "scrollback",
                    "Control the scrollback in the window");
    ctrl_editbox(s, "Lines of scrollback", 's', 50,
                 HELPCTX(window_scrollback),
                 conf_editbox_handler, I(CONF_savelines), ED_INT);
    ctrl_checkbox(s, "Display scrollbar", 'd',
                  HELPCTX(window_scrollback),
                  conf_checkbox_handler, I(CONF_scrollbar));
    ctrl_checkbox(s, "Reset scrollback on keypress", 'k',
                  HELPCTX(window_scrollback),
                  conf_checkbox_handler, I(CONF_scroll_on_key));
    ctrl_checkbox(s, "Reset scrollback on display activity", 'p',
                  HELPCTX(window_scrollback),
                  conf_checkbox_handler, I(CONF_scroll_on_disp));
    ctrl_checkbox(s, "Push erased text into scrollback", 'e',
                  HELPCTX(window_erased),
                  conf_checkbox_handler,
                  I(CONF_erase_to_scrollback));

    /*
     * The Window/Appearance panel.
     */
    str = dupprintf("Configure the appearance of %s's window", appname);
    ctrl_settitle(b, "Window/Appearance", str);
    sfree(str);

    s = ctrl_getset(b, "Window/Appearance", "cursor",
                    "Adjust the use of the cursor");
    ctrl_radiobuttons(s, "Cursor appearance:", NO_SHORTCUT, 3,
                      HELPCTX(appearance_cursor),
                      conf_radiobutton_handler,
                      I(CONF_cursor_type),
                      "Block", 'l', I(CURSOR_BLOCK),
                      "Underline", 'u', I(CURSOR_UNDERLINE),
                      "Vertical line", 'v', I(CURSOR_VERTICAL_LINE));
    ctrl_checkbox(s, "Cursor blinks", 'b',
                  HELPCTX(appearance_cursor),
                  conf_checkbox_handler, I(CONF_blink_cur));

    s = ctrl_getset(b, "Window/Appearance", "font",
                    "Font settings");
    ctrl_fontsel(s, "Font used in the terminal window", 'n',
                 HELPCTX(appearance_font),
                 conf_fontsel_handler, I(CONF_font));

    s = ctrl_getset(b, "Window/Appearance", "mouse",
                    "Adjust the use of the mouse pointer");
    ctrl_checkbox(s, "Hide mouse pointer when typing in window", 'p',
                  HELPCTX(appearance_hidemouse),
                  conf_checkbox_handler, I(CONF_hide_mouseptr));

    s = ctrl_getset(b, "Window/Appearance", "border",
                    "Adjust the window border");
    ctrl_editbox(s, "Gap between text and window edge:", 'e', 20,
                 HELPCTX(appearance_border),
                 conf_editbox_handler,
                 I(CONF_window_border), ED_INT);

    /*
     * The Window/Behaviour panel.
     */
    str = dupprintf("Configure the behaviour of %s's window", appname);
    ctrl_settitle(b, "Window/Behaviour", str);
    sfree(str);

    s = ctrl_getset(b, "Window/Behaviour", "title",
                    "Adjust the behaviour of the window title");
    ctrl_editbox(s, "Window title:", 't', 100,
                 HELPCTX(appearance_title),
                 conf_editbox_handler, I(CONF_wintitle), ED_STR);
    ctrl_checkbox(s, "Separate window and icon titles", 'i',
                  HELPCTX(appearance_title),
                  conf_checkbox_handler,
                  I(CHECKBOX_INVERT | CONF_win_name_always));

    s = ctrl_getset(b, "Window/Behaviour", "main", NULL);
    ctrl_checkbox(s, "Warn before closing window", 'w',
                  HELPCTX(behaviour_closewarn),
                  conf_checkbox_handler, I(CONF_warn_on_close));

    /*
     * The Window/Translation panel.
     */
    ctrl_settitle(b, "Window/Translation",
                  "Options controlling character set translation");

    s = ctrl_getset(b, "Window/Translation", "trans",
                    "Character set translation");
    ctrl_combobox(s, "Remote character set:",
                  'r', 100, HELPCTX(translation_codepage),
                  codepage_handler, P(NULL), P(NULL));

    s = ctrl_getset(b, "Window/Translation", "tweaks", NULL);
    ctrl_checkbox(s, "Treat CJK ambiguous characters as wide", 'w',
                  HELPCTX(translation_cjk_ambig_wide),
                  conf_checkbox_handler, I(CONF_cjk_ambig_wide));

    str = dupprintf("Adjust how %s handles line drawing characters", appname);
    s = ctrl_getset(b, "Window/Translation", "linedraw", str);
    sfree(str);
    ctrl_radiobuttons(
        s, "Handling of line drawing characters:", NO_SHORTCUT,1,
        HELPCTX(translation_linedraw),
        conf_radiobutton_handler, I(CONF_vtmode),
        "Use Unicode line drawing code points",'u',I(VT_UNICODE),
        "Poor man's line drawing (+, - and |)",'p',I(VT_POORMAN));
    ctrl_checkbox(s, "Copy and paste line drawing characters as lqqqk",'d',
                  HELPCTX(selection_linedraw),
                  conf_checkbox_handler, I(CONF_rawcnp));
    ctrl_checkbox(s, "Enable VT100 line drawing even in UTF-8 mode",'8',
                  HELPCTX(translation_utf8linedraw),
                  conf_checkbox_handler, I(CONF_utf8linedraw));

    /*
     * The Window/Selection panel.
     */
    ctrl_settitle(b, "Window/Selection", "Options controlling copy and paste");

    s = ctrl_getset(b, "Window/Selection", "mouse",
                    "Control use of mouse");
    ctrl_checkbox(s, "Shift overrides application's use of mouse", 'p',
                  HELPCTX(selection_shiftdrag),
                  conf_checkbox_handler, I(CONF_mouse_override));
    ctrl_radiobuttons(s,
                      "Default selection mode (Alt+drag does the other one):",
                      NO_SHORTCUT, 2,
                      HELPCTX(selection_rect),
                      conf_radiobutton_bool_handler,
                      I(CONF_rect_select),
                      "Normal", 'n', I(false),
                      "Rectangular block", 'r', I(true));

    s = ctrl_getset(b, "Window/Selection", "clipboards",
                    "Assign copy/paste actions to clipboards");
    ctrl_checkbox(s, "Auto-copy selected text to "
                  CLIPNAME_EXPLICIT_OBJECT,
                  NO_SHORTCUT, HELPCTX(selection_autocopy),
                  conf_checkbox_handler, I(CONF_mouseautocopy));
    clipboard_control(s, "Mouse paste action:", NO_SHORTCUT, 60,
                      HELPCTX(selection_clipactions),
                      CONF_mousepaste, CONF_mousepaste_custom);
    clipboard_control(s, "{Ctrl,Shift} + Ins:", NO_SHORTCUT, 60,
                      HELPCTX(selection_clipactions),
                      CONF_ctrlshiftins, CONF_ctrlshiftins_custom);
    clipboard_control(s, "Ctrl + Shift + {C,V}:", NO_SHORTCUT, 60,
                      HELPCTX(selection_clipactions),
                      CONF_ctrlshiftcv, CONF_ctrlshiftcv_custom);

    s = ctrl_getset(b, "Window/Selection", "paste",
                    "Control pasting of text from clipboard to terminal");
    ctrl_checkbox(s, "Permit control characters in pasted text",
                  NO_SHORTCUT, HELPCTX(selection_pastectrl),
                  conf_checkbox_handler, I(CONF_paste_controls));

    /*
     * The Window/Selection/Copy panel.
     */
    ctrl_settitle(b, "Window/Selection/Copy",
                  "Options controlling copying from terminal to clipboard");

    s = ctrl_getset(b, "Window/Selection/Copy", "charclass",
                    "Classes of character that group together");
    ccd = (struct charclass_data *)
        ctrl_alloc(b, sizeof(struct charclass_data));
    ccd->listbox = ctrl_listbox(s, "Character classes:", 'e',
                                HELPCTX(copy_charclasses),
                                charclass_handler, P(ccd));
    ccd->listbox->listbox.multisel = 1;
    ccd->listbox->listbox.ncols = 4;
    ccd->listbox->listbox.percentages = snewn(4, int);
    ccd->listbox->listbox.percentages[0] = 15;
    ccd->listbox->listbox.percentages[1] = 25;
    ccd->listbox->listbox.percentages[2] = 20;
    ccd->listbox->listbox.percentages[3] = 40;
    ctrl_columns(s, 2, 67, 33);
    ccd->editbox = ctrl_editbox(s, "Set to class", 't', 50,
                                HELPCTX(copy_charclasses),
                                charclass_handler, P(ccd), P(NULL));
    ccd->editbox->column = 0;
    ccd->button = ctrl_pushbutton(s, "Set", 's',
                                  HELPCTX(copy_charclasses),
                                  charclass_handler, P(ccd));
    ccd->button->column = 1;
    ctrl_columns(s, 1, 100);

    /*
     * The Window/Colours panel.
     */
    ctrl_settitle(b, "Window/Colours", "Options controlling use of colours");

    s = ctrl_getset(b, "Window/Colours", "general",
                    "General options for colour usage");
    ctrl_checkbox(s, "Allow terminal to specify ANSI colours", 'i',
                  HELPCTX(colours_ansi),
                  conf_checkbox_handler, I(CONF_ansi_colour));
    ctrl_checkbox(s, "Allow terminal to use xterm 256-colour mode", '2',
                  HELPCTX(colours_xterm256), conf_checkbox_handler,
                  I(CONF_xterm_256_colour));
    ctrl_checkbox(s, "Allow terminal to use 24-bit colours", '4',
                  HELPCTX(colours_truecolour), conf_checkbox_handler,
                  I(CONF_true_colour));
    ctrl_radiobuttons(s, "Indicate bolded text by changing:", 'b', 3,
                      HELPCTX(colours_bold),
                      conf_radiobutton_handler, I(CONF_bold_style),
                      "The font", I(BOLD_STYLE_FONT),
                      "The colour", I(BOLD_STYLE_COLOUR),
                      "Both", I(BOLD_STYLE_FONT | BOLD_STYLE_COLOUR));

    str = dupprintf("Adjust the precise colours %s displays", appname);
    s = ctrl_getset(b, "Window/Colours", "adjust", str);
    sfree(str);
    ctrl_text(s, "Select a colour from the list, and then click the"
              " Modify button to change its appearance.",
              HELPCTX(colours_config));
    ctrl_columns(s, 2, 67, 33);
    cd = (struct colour_data *)ctrl_alloc(b, sizeof(struct colour_data));
    cd->listbox = ctrl_listbox(s, "Select a colour to adjust:", 'u',
                               HELPCTX(colours_config), colour_handler, P(cd));
    cd->listbox->column = 0;
    cd->listbox->listbox.height = 7;
    c = ctrl_text(s, "RGB value:", HELPCTX(colours_config));
    c->column = 1;
    cd->redit = ctrl_editbox(s, "Red", 'r', 50, HELPCTX(colours_config),
                             colour_handler, P(cd), P(NULL));
    cd->redit->column = 1;
    cd->gedit = ctrl_editbox(s, "Green", 'n', 50, HELPCTX(colours_config),
                             colour_handler, P(cd), P(NULL));
    cd->gedit->column = 1;
    cd->bedit = ctrl_editbox(s, "Blue", 'e', 50, HELPCTX(colours_config),
                             colour_handler, P(cd), P(NULL));
    cd->bedit->column = 1;
    cd->button = ctrl_pushbutton(s, "Modify", 'm', HELPCTX(colours_config),
                                 colour_handler, P(cd));
    cd->button->column = 1;
    ctrl_columns(s, 1, 100);

    /*
     * The Connection panel. This doesn't show up if we're in a
     * non-network utility such as pterm. We tell this by being
     * passed a protocol < 0.
     */
    if (protocol >= 0) {
        ctrl_settitle(b, "Connection", "Options controlling the connection");

        s = ctrl_getset(b, "Connection", "keepalive",
                        "Sending of null packets to keep session active");
        ctrl_editbox(s, "Seconds between keepalives (0 to turn off)", 'k', 20,
                     HELPCTX(connection_keepalive),
                     conf_editbox_handler, I(CONF_ping_interval), ED_INT);

        if (!midsession) {
            s = ctrl_getset(b, "Connection", "tcp",
                            "Low-level TCP connection options");
            ctrl_checkbox(s, "Disable Nagle's algorithm (TCP_NODELAY option)",
                          'n', HELPCTX(connection_nodelay),
                          conf_checkbox_handler,
                          I(CONF_tcp_nodelay));
            ctrl_checkbox(s, "Enable TCP keepalives (SO_KEEPALIVE option)",
                          'p', HELPCTX(connection_tcpkeepalive),
                          conf_checkbox_handler,
                          I(CONF_tcp_keepalives));
#ifndef NO_IPV6
            s = ctrl_getset(b, "Connection", "ipversion",
                            "Internet protocol version");
            ctrl_radiobuttons(s, NULL, NO_SHORTCUT, 3,
                              HELPCTX(connection_ipversion),
                              conf_radiobutton_handler,
                              I(CONF_addressfamily),
                              "Auto", 'u', I(ADDRTYPE_UNSPEC),
                              "IPv4", '4', I(ADDRTYPE_IPV4),
                              "IPv6", '6', I(ADDRTYPE_IPV6));
#endif

            {
                const char *label = backend_vt_from_proto(PROT_SSH) ?
                    "Logical name of remote host (e.g. for SSH key lookup):" :
                    "Logical name of remote host:";
                s = ctrl_getset(b, "Connection", "identity",
                                "Logical name of remote host");
                ctrl_editbox(s, label, 'm', 100,
                             HELPCTX(connection_loghost),
                             conf_editbox_handler, I(CONF_loghost), ED_STR);
            }
        }

        /*
         * A sub-panel Connection/Data, containing options that
         * decide on data to send to the server.
         */
        if (!midsession) {
            ctrl_settitle(b, "Connection/Data", "Data to send to the server");

            s = ctrl_getset(b, "Connection/Data", "login",
                            "Login details");
            ctrl_editbox(s, "Auto-login username", 'u', 50,
                         HELPCTX(connection_username),
                         conf_editbox_handler, I(CONF_username), ED_STR);
            {
                /* We assume the local username is sufficiently stable
                 * to include on the dialog box. */
                char *user = get_username();
                char *userlabel = dupprintf("Use system username (%s)",
                                            user ? user : "");
                sfree(user);
                ctrl_radiobuttons(s, "When username is not specified:", 'n', 4,
                                  HELPCTX(connection_username_from_env),
                                  conf_radiobutton_bool_handler,
                                  I(CONF_username_from_env),
                                  "Prompt", I(false),
                                  userlabel, I(true));
                sfree(userlabel);
            }

            s = ctrl_getset(b, "Connection/Data", "term",
                            "Terminal details");
            ctrl_editbox(s, "Terminal-type string", 't', 50,
                         HELPCTX(connection_termtype),
                         conf_editbox_handler, I(CONF_termtype), ED_STR);
            ctrl_editbox(s, "Terminal speeds", 's', 50,
                         HELPCTX(connection_termspeed),
                         conf_editbox_handler, I(CONF_termspeed), ED_STR);

            s = ctrl_getset(b, "Connection/Data", "env",
                            "Environment variables");
            ctrl_columns(s, 2, 80, 20);
            ed = (struct environ_data *)
                ctrl_alloc(b, sizeof(struct environ_data));
            ed->varbox = ctrl_editbox(s, "Variable", 'v', 60,
                                      HELPCTX(telnet_environ),
                                      environ_handler, P(ed), P(NULL));
            ed->varbox->column = 0;
            ed->valbox = ctrl_editbox(s, "Value", 'l', 60,
                                      HELPCTX(telnet_environ),
                                      environ_handler, P(ed), P(NULL));
            ed->valbox->column = 0;
            ed->addbutton = ctrl_pushbutton(s, "Add", 'd',
                                            HELPCTX(telnet_environ),
                                            environ_handler, P(ed));
            ed->addbutton->column = 1;
            ed->rembutton = ctrl_pushbutton(s, "Remove", 'r',
                                            HELPCTX(telnet_environ),
                                            environ_handler, P(ed));
            ed->rembutton->column = 1;
            ctrl_columns(s, 1, 100);
            ed->listbox = ctrl_listbox(s, NULL, NO_SHORTCUT,
                                       HELPCTX(telnet_environ),
                                       environ_handler, P(ed));
            ed->listbox->listbox.height = 3;
            ed->listbox->listbox.ncols = 2;
            ed->listbox->listbox.percentages = snewn(2, int);
            ed->listbox->listbox.percentages[0] = 30;
            ed->listbox->listbox.percentages[1] = 70;
        }

    }

    if (!midsession) {
        /*
         * The Connection/Proxy panel.
         */
        ctrl_settitle(b, "Connection/Proxy",
                      "Options controlling proxy usage");

        s = ctrl_getset(b, "Connection/Proxy", "basics", NULL);
        c = ctrl_droplist(s, "Proxy type:", 't', 70,
                          HELPCTX(proxy_type), proxy_type_handler, I(0));
        ctrl_columns(s, 2, 80, 20);
        c = ctrl_editbox(s, "Proxy hostname", 'y', 100,
                         HELPCTX(proxy_main),
                         conf_editbox_handler,
                         I(CONF_proxy_host), ED_STR);
        c->column = 0;
        c = ctrl_editbox(s, "Port", 'p', 100,
                         HELPCTX(proxy_main),
                         conf_editbox_handler,
                         I(CONF_proxy_port),
                         ED_INT);
        c->column = 1;
        ctrl_columns(s, 1, 100);
        ctrl_editbox(s, "Exclude Hosts/IPs", 'e', 100,
                     HELPCTX(proxy_exclude),
                     conf_editbox_handler,
                     I(CONF_proxy_exclude_list), ED_STR);
        ctrl_checkbox(s, "Consider proxying local host connections", 'x',
                      HELPCTX(proxy_exclude),
                      conf_checkbox_handler,
                      I(CONF_even_proxy_localhost));
        ctrl_radiobuttons(s, "Do DNS name lookup at proxy end:", 'd', 3,
                          HELPCTX(proxy_dns),
                          conf_radiobutton_handler,
                          I(CONF_proxy_dns),
                          "No", I(FORCE_OFF),
                          "Auto", I(AUTO),
                          "Yes", I(FORCE_ON));
        ctrl_editbox(s, "Username", 'u', 60,
                     HELPCTX(proxy_auth),
                     conf_editbox_handler,
                     I(CONF_proxy_username), ED_STR);
        c = ctrl_editbox(s, "Password", 'w', 60,
                         HELPCTX(proxy_auth),
                         conf_editbox_handler,
                         I(CONF_proxy_password), ED_STR);
        c->editbox.password = true;
        ctrl_editbox(s, "Command to send to proxy (for some types)", 'm', 100,
                     HELPCTX(proxy_command),
                     conf_editbox_handler,
                     I(CONF_proxy_telnet_command), ED_STR);

        ctrl_radiobuttons(s, "Print proxy diagnostics "
                          "in the terminal window", 'r', 5,
                          HELPCTX(proxy_logging),
                          conf_radiobutton_handler,
                          I(CONF_proxy_log_to_term),
                          "No", I(FORCE_OFF),
                          "Yes", I(FORCE_ON),
                          "Only until session starts", I(AUTO));
    }

    /*
     * Each per-protocol configuration GUI panel is conditionally
     * displayed. We don't display it if this binary doesn't contain a
     * backend for its protocol at all; we don't display it if we're
     * already in mid-session with a different protocol selected; and
     * even if we _do_ have this protocol selected, we don't display
     * the panel if the protocol doesn't permit any mid-session
     * reconfiguration anyway.
     */

#define DISPLAY_RECONFIGURABLE_PROTOCOL(which_proto) \
    (backend_vt_from_proto(which_proto) && \
     (!midsession || protocol == (which_proto)))
#define DISPLAY_NON_RECONFIGURABLE_PROTOCOL(which_proto) \
    (backend_vt_from_proto(which_proto) && !midsession)

    if (DISPLAY_RECONFIGURABLE_PROTOCOL(PROT_SSH) ||
        DISPLAY_RECONFIGURABLE_PROTOCOL(PROT_SSHCONN)) {
        /*
         * The Connection/SSH panel.
         */
        ctrl_settitle(b, "Connection/SSH",
                      "Options controlling SSH connections");

        /* SSH-1 or connection-sharing downstream */
        if (midsession && (protcfginfo == 1 || protcfginfo == -1)) {
            s = ctrl_getset(b, "Connection/SSH", "disclaimer", NULL);
            ctrl_text(s, "Nothing on this panel may be reconfigured in mid-"
                      "session; it is only here so that sub-panels of it can "
                      "exist without looking strange.", HELPCTX(no_help));
        }

        if (!midsession) {

            s = ctrl_getset(b, "Connection/SSH", "data",
                            "Data to send to the server");
            ctrl_editbox(s, "Remote command:", 'r', 100,
                         HELPCTX(ssh_command),
                         conf_editbox_handler, I(CONF_remote_cmd), ED_STR);

            s = ctrl_getset(b, "Connection/SSH", "protocol", "Protocol options");
            ctrl_checkbox(s, "Don't start a shell or command at all", 'n',
                          HELPCTX(ssh_noshell),
                          conf_checkbox_handler,
                          I(CONF_ssh_no_shell));
        }

        if (!midsession || !(protcfginfo == 1 || protcfginfo == -1)) {
            s = ctrl_getset(b, "Connection/SSH", "protocol", "Protocol options");

            ctrl_checkbox(s, "Enable compression", 'e',
                          HELPCTX(ssh_compress),
                          conf_checkbox_handler,
                          I(CONF_compression));
        }

        if (!midsession) {
            s = ctrl_getset(b, "Connection/SSH", "sharing", "Sharing an SSH connection between PuTTY tools");

            ctrl_checkbox(s, "Share SSH connections if possible", 's',
                          HELPCTX(ssh_share),
                          conf_checkbox_handler,
                          I(CONF_ssh_connection_sharing));

            ctrl_text(s, "Permitted roles in a shared connection:",
                      HELPCTX(ssh_share));
            ctrl_checkbox(s, "Upstream (connecting to the real server)", 'u',
                          HELPCTX(ssh_share),
                          conf_checkbox_handler,
                          I(CONF_ssh_connection_sharing_upstream));
            ctrl_checkbox(s, "Downstream (connecting to the upstream PuTTY)", 'd',
                          HELPCTX(ssh_share),
                          conf_checkbox_handler,
                          I(CONF_ssh_connection_sharing_downstream));
        }

        if (!midsession) {
            s = ctrl_getset(b, "Connection/SSH", "protocol", "Protocol options");

            ctrl_radiobuttons(s, "SSH protocol version:", NO_SHORTCUT, 2,
                              HELPCTX(ssh_protocol),
                              conf_radiobutton_handler,
                              I(CONF_sshprot),
                              "2", '2', I(3),
                              "1 (INSECURE)", '1', I(0));
        }

        /*
         * The Connection/SSH/Kex panel. (Owing to repeat key
         * exchange, much of this is meaningful in mid-session _if_
         * we're using SSH-2 and are not a connection-sharing
         * downstream, or haven't decided yet.)
         */
        if (protcfginfo != 1 && protcfginfo != -1) {
            ctrl_settitle(b, "Connection/SSH/Kex",
                          "Options controlling SSH key exchange");

            s = ctrl_getset(b, "Connection/SSH/Kex", "main",
                            "Key exchange algorithm options");
            c = ctrl_draglist(s, "Algorithm selection policy:", 's',
                              HELPCTX(ssh_kexlist),
                              kexlist_handler, P(NULL));
            c->listbox.height = 10;
#ifndef NO_GSSAPI
            ctrl_checkbox(s, "Attempt GSSAPI key exchange",
                          'k', HELPCTX(ssh_gssapi),
                          conf_checkbox_handler,
                          I(CONF_try_gssapi_kex));
#endif

            s = ctrl_getset(b, "Connection/SSH/Kex", "repeat",
                            "Options controlling key re-exchange");

            ctrl_editbox(s, "Max minutes before rekey (0 for no limit)", 't', 20,
                         HELPCTX(ssh_kex_repeat),
                         conf_editbox_handler,
                         I(CONF_ssh_rekey_time),
                         ED_INT);
#ifndef NO_GSSAPI
            ctrl_editbox(s, "Minutes between GSS checks (0 for never)", NO_SHORTCUT, 20,
                         HELPCTX(ssh_kex_repeat),
                         conf_editbox_handler,
                         I(CONF_gssapirekey),
                         ED_INT);
#endif
            ctrl_editbox(s, "Max data before rekey (0 for no limit)", 'x', 20,
                         HELPCTX(ssh_kex_repeat),
                         conf_editbox_handler,
                         I(CONF_ssh_rekey_data),
                         ED_STR);
            ctrl_text(s, "(Use 1M for 1 megabyte, 1G for 1 gigabyte etc)",
                      HELPCTX(ssh_kex_repeat));
        }

        /*
         * The 'Connection/SSH/Host keys' panel.
         */
        if (protcfginfo != 1 && protcfginfo != -1) {
            ctrl_settitle(b, "Connection/SSH/Host keys",
                          "Options controlling SSH host keys");

            s = ctrl_getset(b, "Connection/SSH/Host keys", "main",
                            "Host key algorithm preference");
            c = ctrl_draglist(s, "Algorithm selection policy:", 's',
                              HELPCTX(ssh_hklist),
                              hklist_handler, P(NULL));
            c->listbox.height = 5;

            ctrl_checkbox(s, "Prefer algorithms for which a host key is known",
                          'p', HELPCTX(ssh_hk_known), conf_checkbox_handler,
                          I(CONF_ssh_prefer_known_hostkeys));
        }

        /*
         * Manual host key configuration is irrelevant mid-session,
         * as we enforce that the host key for rekeys is the
         * same as that used at the start of the session.
         */
        if (!midsession) {
            s = ctrl_getset(b, "Connection/SSH/Host keys", "hostkeys",
                            "Manually configure host keys for this connection");

            ctrl_columns(s, 2, 75, 25);
            c = ctrl_text(s, "Host keys or fingerprints to accept:",
                          HELPCTX(ssh_kex_manual_hostkeys));
            c->column = 0;
            /* You want to select from the list, _then_ hit Remove. So
             * tab order should be that way round. */
            mh = (struct manual_hostkey_data *)
                ctrl_alloc(b,sizeof(struct manual_hostkey_data));
            mh->rembutton = ctrl_pushbutton(s, "Remove", 'r',
                                            HELPCTX(ssh_kex_manual_hostkeys),
                                            manual_hostkey_handler, P(mh));
            mh->rembutton->column = 1;
            mh->rembutton->delay_taborder = true;
            mh->listbox = ctrl_listbox(s, NULL, NO_SHORTCUT,
                                       HELPCTX(ssh_kex_manual_hostkeys),
                                       manual_hostkey_handler, P(mh));
            /* This list box can't be very tall, because there's not
             * much room in the pane on Windows at least. This makes
             * it become really unhelpful if a horizontal scrollbar
             * appears, so we suppress that. */
            mh->listbox->listbox.height = 2;
            mh->listbox->listbox.hscroll = false;
            ctrl_tabdelay(s, mh->rembutton);
            mh->keybox = ctrl_editbox(s, "Key", 'k', 80,
                                      HELPCTX(ssh_kex_manual_hostkeys),
                                      manual_hostkey_handler, P(mh), P(NULL));
            mh->keybox->column = 0;
            mh->addbutton = ctrl_pushbutton(s, "Add key", 'y',
                                            HELPCTX(ssh_kex_manual_hostkeys),
                                            manual_hostkey_handler, P(mh));
            mh->addbutton->column = 1;
            ctrl_columns(s, 1, 100);
        }

        /*
         * But there's no reason not to forbid access to the host CA
         * configuration box, which is common across sessions in any
         * case.
         */
        s = ctrl_getset(b, "Connection/SSH/Host keys", "ca",
                        "Configure trusted certification authorities");
        c = ctrl_pushbutton(s, "Configure host CAs", NO_SHORTCUT,
                            HELPCTX(ssh_kex_cert),
                            host_ca_button_handler, I(0));

        if (!midsession || !(protcfginfo == 1 || protcfginfo == -1)) {
            /*
             * The Connection/SSH/Cipher panel.
             */
            ctrl_settitle(b, "Connection/SSH/Cipher",
                          "Options controlling SSH encryption");

            s = ctrl_getset(b, "Connection/SSH/Cipher",
                            "encryption", "Encryption options");
            c = ctrl_draglist(s, "Encryption cipher selection policy:", 's',
                              HELPCTX(ssh_ciphers),
                              cipherlist_handler, P(NULL));
            c->listbox.height = 6;

            ctrl_checkbox(s, "Enable legacy use of single-DES in SSH-2", 'i',
                          HELPCTX(ssh_ciphers),
                          conf_checkbox_handler,
                          I(CONF_ssh2_des_cbc));
        }

        if (!midsession) {

            /*
             * The Connection/SSH/Auth panel.
             */
            ctrl_settitle(b, "Connection/SSH/Auth",
                          "Options controlling SSH authentication");

            s = ctrl_getset(b, "Connection/SSH/Auth", "main", NULL);
            ctrl_checkbox(s, "Display pre-authentication banner (SSH-2 only)",
                          'd', HELPCTX(ssh_auth_banner),
                          conf_checkbox_handler,
                          I(CONF_ssh_show_banner));
            ctrl_checkbox(s, "Bypass authentication entirely (SSH-2 only)", 'b',
                          HELPCTX(ssh_auth_bypass),
                          conf_checkbox_handler,
                          I(CONF_ssh_no_userauth));
            ctrl_checkbox(s, "Disconnect if authentication succeeds trivially",
                          'n', HELPCTX(ssh_no_trivial_userauth),
                          conf_checkbox_handler,
                          I(CONF_ssh_no_trivial_userauth));

            s = ctrl_getset(b, "Connection/SSH/Auth", "methods",
                            "Authentication methods");
            ctrl_checkbox(s, "Attempt authentication using Pageant", 'p',
                          HELPCTX(ssh_auth_pageant),
                          conf_checkbox_handler,
                          I(CONF_tryagent));
            ctrl_checkbox(s, "Attempt TIS or CryptoCard auth (SSH-1)", 'm',
                          HELPCTX(ssh_auth_tis),
                          conf_checkbox_handler,
                          I(CONF_try_tis_auth));
            ctrl_checkbox(s, "Attempt \"keyboard-interactive\" auth (SSH-2)",
                          'i', HELPCTX(ssh_auth_ki),
                          conf_checkbox_handler,
                          I(CONF_try_ki_auth));

            s = ctrl_getset(b, "Connection/SSH/Auth", "aux",
                            "Other authentication-related options");
            ctrl_checkbox(s, "Allow agent forwarding", 'f',
                          HELPCTX(ssh_auth_agentfwd),
                          conf_checkbox_handler, I(CONF_agentfwd));
            ctrl_checkbox(s, "Allow attempted changes of username in SSH-2", NO_SHORTCUT,
                          HELPCTX(ssh_auth_changeuser),
                          conf_checkbox_handler,
                          I(CONF_change_username));

            ctrl_settitle(b, "Connection/SSH/Auth/Credentials",
                          "Credentials to authenticate with");

            s = ctrl_getset(b, "Connection/SSH/Auth/Credentials", "publickey",
                            "Public-key authentication");
            ctrl_filesel(s, "Private key file for authentication:", 'k',
                         FILTER_KEY_FILES, false, "Select private key file",
                         HELPCTX(ssh_auth_privkey),
                         conf_filesel_handler, I(CONF_keyfile));
            ctrl_filesel(s, "Certificate to use with the private key "
                         "(optional):", 'e',
                         FILTER_ALL_FILES, false, "Select certificate file",
                         HELPCTX(ssh_auth_cert),
                         conf_filesel_handler, I(CONF_detached_cert));

            s = ctrl_getset(b, "Connection/SSH/Auth/Credentials", "plugin",
                            "Plugin to provide authentication responses");
            ctrl_editbox(s, "Plugin command to run", NO_SHORTCUT, 100,
                         HELPCTX(ssh_auth_plugin),
                         conf_editbox_handler, I(CONF_auth_plugin), ED_STR);
#ifndef NO_GSSAPI
            /*
             * Connection/SSH/Auth/GSSAPI, which sadly won't fit on
             * the main Auth panel.
             */
            ctrl_settitle(b, "Connection/SSH/Auth/GSSAPI",
                          "Options controlling GSSAPI authentication");
            s = ctrl_getset(b, "Connection/SSH/Auth/GSSAPI", "gssapi", NULL);

            ctrl_checkbox(s, "Attempt GSSAPI authentication (SSH-2 only)",
                          't', HELPCTX(ssh_gssapi),
                          conf_checkbox_handler,
                          I(CONF_try_gssapi_auth));

            ctrl_checkbox(s, "Attempt GSSAPI key exchange (SSH-2 only)",
                          'k', HELPCTX(ssh_gssapi),
                          conf_checkbox_handler,
                          I(CONF_try_gssapi_kex));

            ctrl_checkbox(s, "Allow GSSAPI credential delegation", 'l',
                          HELPCTX(ssh_gssapi_delegation),
                          conf_checkbox_handler,
                          I(CONF_gssapifwd));

            /*
             * GSSAPI library selection.
             */
            if (ngsslibs > 1) {
                c = ctrl_draglist(s, "Preference order for GSSAPI libraries:",
                                  'p', HELPCTX(ssh_gssapi_libraries),
                                  gsslist_handler, P(NULL));
                c->listbox.height = ngsslibs;

                /*
                 * I currently assume that if more than one GSS
                 * library option is available, then one of them is
                 * 'user-supplied' and so we should present the
                 * following file selector. This is at least half-
                 * reasonable, because if we're using statically
                 * linked GSSAPI then there will only be one option
                 * and no way to load from a user-supplied library,
                 * whereas if we're using dynamic libraries then
                 * there will almost certainly be some default
                 * option in addition to a user-supplied path. If
                 * anyone ever ports PuTTY to a system on which
                 * dynamic-library GSSAPI is available but there is
                 * absolutely no consensus on where to keep the
                 * libraries, there'll need to be a flag alongside
                 * ngsslibs to control whether the file selector is
                 * displayed.
                 */

                ctrl_filesel(s, "User-supplied GSSAPI library path:", 's',
                             FILTER_DYNLIB_FILES, false, "Select library file",
                             HELPCTX(ssh_gssapi_libraries),
                             conf_filesel_handler,
                             I(CONF_ssh_gss_custom));
            }
#endif
        }

        if (!midsession) {
            /*
             * The Connection/SSH/TTY panel.
             */
            ctrl_settitle(b, "Connection/SSH/TTY", "Remote terminal settings");

            s = ctrl_getset(b, "Connection/SSH/TTY", "sshtty", NULL);
            ctrl_checkbox(s, "Don't allocate a pseudo-terminal", 'p',
                          HELPCTX(ssh_nopty),
                          conf_checkbox_handler,
                          I(CONF_nopty));

            s = ctrl_getset(b, "Connection/SSH/TTY", "ttymodes",
                            "Terminal modes");
            td = (struct ttymodes_data *)
                ctrl_alloc(b, sizeof(struct ttymodes_data));
            ctrl_text(s, "Terminal modes to send:", HELPCTX(ssh_ttymodes));
            td->listbox = ctrl_listbox(s, NULL, NO_SHORTCUT,
                                       HELPCTX(ssh_ttymodes),
                                       ttymodes_handler, P(td));
            td->listbox->listbox.height = 8;
            td->listbox->listbox.ncols = 2;
            td->listbox->listbox.percentages = snewn(2, int);
            td->listbox->listbox.percentages[0] = 40;
            td->listbox->listbox.percentages[1] = 60;
            ctrl_columns(s, 2, 75, 25);
            c = ctrl_text(s, "For selected mode, send:", HELPCTX(ssh_ttymodes));
            c->column = 0;
            td->setbutton = ctrl_pushbutton(s, "Set", 's',
                                            HELPCTX(ssh_ttymodes),
                                            ttymodes_handler, P(td));
            td->setbutton->column = 1;
            td->setbutton->delay_taborder = true;
            ctrl_columns(s, 1, 100);        /* column break */
            /* Bit of a hack to get the value radio buttons and
             * edit-box on the same row. */
            ctrl_columns(s, 2, 75, 25);
            td->valradio = ctrl_radiobuttons(s, NULL, NO_SHORTCUT, 3,
                                             HELPCTX(ssh_ttymodes),
                                             ttymodes_handler, P(td),
                                             "Auto", NO_SHORTCUT, P(NULL),
                                             "Nothing", NO_SHORTCUT, P(NULL),
                                             "This:", NO_SHORTCUT, P(NULL));
            td->valradio->column = 0;
            td->valbox = ctrl_editbox(s, NULL, NO_SHORTCUT, 100,
                                      HELPCTX(ssh_ttymodes),
                                      ttymodes_handler, P(td), P(NULL));
            td->valbox->column = 1;
            td->valbox->align_next_to = td->valradio;
            ctrl_tabdelay(s, td->setbutton);
        }

        if (!midsession) {
            /*
             * The Connection/SSH/X11 panel.
             */
            ctrl_settitle(b, "Connection/SSH/X11",
                          "Options controlling SSH X11 forwarding");

            s = ctrl_getset(b, "Connection/SSH/X11", "x11", "X11 forwarding");
            ctrl_checkbox(s, "Enable X11 forwarding", 'e',
                          HELPCTX(ssh_tunnels_x11),
                          conf_checkbox_handler,I(CONF_x11_forward));
            ctrl_editbox(s, "X display location", 'x', 50,
                         HELPCTX(ssh_tunnels_x11),
                         conf_editbox_handler, I(CONF_x11_display), ED_STR);
            ctrl_radiobuttons(s, "Remote X11 authentication protocol", 'u', 2,
                              HELPCTX(ssh_tunnels_x11auth),
                              conf_radiobutton_handler,
                              I(CONF_x11_auth),
                              "MIT-Magic-Cookie-1", I(X11_MIT),
                              "XDM-Authorization-1", I(X11_XDM));
        }

        /*
         * The Tunnels panel _is_ still available in mid-session.
         */
        ctrl_settitle(b, "Connection/SSH/Tunnels",
                      "Options controlling SSH port forwarding");

        s = ctrl_getset(b, "Connection/SSH/Tunnels", "portfwd",
                        "Port forwarding");
        ctrl_checkbox(s, "Local ports accept connections from other hosts",'t',
                      HELPCTX(ssh_tunnels_portfwd_localhost),
                      conf_checkbox_handler,
                      I(CONF_lport_acceptall));
        ctrl_checkbox(s, "Remote ports do the same (SSH-2 only)", 'p',
                      HELPCTX(ssh_tunnels_portfwd_localhost),
                      conf_checkbox_handler,
                      I(CONF_rport_acceptall));

        ctrl_columns(s, 3, 55, 20, 25);
        c = ctrl_text(s, "Forwarded ports:", HELPCTX(ssh_tunnels_portfwd));
        c->column = COLUMN_FIELD(0,2);
        /* You want to select from the list, _then_ hit Remove. So tab order
         * should be that way round. */
        pfd = (struct portfwd_data *)ctrl_alloc(b,sizeof(struct portfwd_data));
        pfd->rembutton = ctrl_pushbutton(s, "Remove", 'r',
                                         HELPCTX(ssh_tunnels_portfwd),
                                         portfwd_handler, P(pfd));
        pfd->rembutton->column = 2;
        pfd->rembutton->delay_taborder = true;
        pfd->listbox = ctrl_listbox(s, NULL, NO_SHORTCUT,
                                    HELPCTX(ssh_tunnels_portfwd),
                                    portfwd_handler, P(pfd));
        pfd->listbox->listbox.height = 3;
        pfd->listbox->listbox.ncols = 2;
        pfd->listbox->listbox.percentages = snewn(2, int);
        pfd->listbox->listbox.percentages[0] = 20;
        pfd->listbox->listbox.percentages[1] = 80;
        ctrl_tabdelay(s, pfd->rembutton);
        ctrl_text(s, "Add new forwarded port:", HELPCTX(ssh_tunnels_portfwd));
        /* You want to enter source, destination and type, _then_ hit Add.
         * Again, we adjust the tab order to reflect this. */
        pfd->addbutton = ctrl_pushbutton(s, "Add", 'd',
                                         HELPCTX(ssh_tunnels_portfwd),
                                         portfwd_handler, P(pfd));
        pfd->addbutton->column = 2;
        pfd->addbutton->delay_taborder = true;
        pfd->sourcebox = ctrl_editbox(s, "Source port", 's', 40,
                                      HELPCTX(ssh_tunnels_portfwd),
                                      portfwd_handler, P(pfd), P(NULL));
        pfd->sourcebox->column = 0;
        pfd->destbox = ctrl_editbox(s, "Destination", 'i', 67,
                                    HELPCTX(ssh_tunnels_portfwd),
                                    portfwd_handler, P(pfd), P(NULL));
        pfd->direction = ctrl_radiobuttons(s, NULL, NO_SHORTCUT, 3,
                                           HELPCTX(ssh_tunnels_portfwd),
                                           portfwd_handler, P(pfd),
                                           "Local", 'l', P(NULL),
                                           "Remote", 'm', P(NULL),
                                           "Dynamic", 'y', P(NULL));
#ifndef NO_IPV6
        pfd->addressfamily =
            ctrl_radiobuttons(s, NULL, NO_SHORTCUT, 3,
                              HELPCTX(ssh_tunnels_portfwd_ipversion),
                              portfwd_handler, P(pfd),
                              "Auto", 'u', I(ADDRTYPE_UNSPEC),
                              "IPv4", '4', I(ADDRTYPE_IPV4),
                              "IPv6", '6', I(ADDRTYPE_IPV6));
#endif
        ctrl_tabdelay(s, pfd->addbutton);
        ctrl_columns(s, 1, 100);

        if (!midsession) {
            /*
             * The Connection/SSH/Bugs panels.
             */
            ctrl_settitle(b, "Connection/SSH/Bugs",
                          "Workarounds for SSH server bugs");

            s = ctrl_getset(b, "Connection/SSH/Bugs", "main",
                            "Detection of known bugs in SSH servers");
            ctrl_droplist(s, "Chokes on SSH-2 ignore messages", '2', 20,
                          HELPCTX(ssh_bugs_ignore2),
                          sshbug_handler, I(CONF_sshbug_ignore2));
            ctrl_droplist(s, "Handles SSH-2 key re-exchange badly", 'k', 20,
                          HELPCTX(ssh_bugs_rekey2),
                          sshbug_handler, I(CONF_sshbug_rekey2));
            ctrl_droplist(s, "Chokes on PuTTY's SSH-2 'winadj' requests", 'j',
                          20, HELPCTX(ssh_bugs_winadj),
                          sshbug_handler, I(CONF_sshbug_winadj));
            ctrl_droplist(s, "Replies to requests on closed channels", 'q', 20,
                          HELPCTX(ssh_bugs_chanreq),
                          sshbug_handler, I(CONF_sshbug_chanreq));
            ctrl_droplist(s, "Ignores SSH-2 maximum packet size", 'x', 20,
                          HELPCTX(ssh_bugs_maxpkt2),
                          sshbug_handler, I(CONF_sshbug_maxpkt2));

            s = ctrl_getset(b, "Connection/SSH/Bugs", "manual",
                            "Manually enabled workarounds");
            ctrl_droplist(s, "Discards data sent before its greeting", 'd', 20,
                          HELPCTX(ssh_bugs_dropstart),
                          sshbug_handler_manual_only,
                          I(CONF_sshbug_dropstart));
            ctrl_droplist(s, "Chokes on PuTTY's full KEXINIT", 'p', 20,
                          HELPCTX(ssh_bugs_filter_kexinit),
                          sshbug_handler_manual_only,
                          I(CONF_sshbug_filter_kexinit));

            ctrl_settitle(b, "Connection/SSH/More bugs",
                          "Further workarounds for SSH server bugs");

            s = ctrl_getset(b, "Connection/SSH/More bugs", "main",
                            "Detection of known bugs in SSH servers");
            ctrl_droplist(s, "Old RSA/SHA2 cert algorithm naming", 'l', 20,
                          HELPCTX(ssh_bugs_rsa_sha2_cert_userauth),
                          sshbug_handler,
                          I(CONF_sshbug_rsa_sha2_cert_userauth));
            ctrl_droplist(s, "Requires padding on SSH-2 RSA signatures", 'p', 20,
                          HELPCTX(ssh_bugs_rsapad2),
                          sshbug_handler, I(CONF_sshbug_rsapad2));
            ctrl_droplist(s, "Only supports pre-RFC4419 SSH-2 DH GEX", 'd', 20,
                          HELPCTX(ssh_bugs_oldgex2),
                          sshbug_handler, I(CONF_sshbug_oldgex2));
            ctrl_droplist(s, "Miscomputes SSH-2 HMAC keys", 'm', 20,
                          HELPCTX(ssh_bugs_hmac2),
                          sshbug_handler, I(CONF_sshbug_hmac2));
            ctrl_droplist(s, "Misuses the session ID in SSH-2 PK auth", 'n', 20,
                          HELPCTX(ssh_bugs_pksessid2),
                          sshbug_handler, I(CONF_sshbug_pksessid2));
            ctrl_droplist(s, "Miscomputes SSH-2 encryption keys", 'e', 20,
                          HELPCTX(ssh_bugs_derivekey2),
                          sshbug_handler, I(CONF_sshbug_derivekey2));
            ctrl_droplist(s, "Chokes on SSH-1 ignore messages", 'i', 20,
                          HELPCTX(ssh_bugs_ignore1),
                          sshbug_handler, I(CONF_sshbug_ignore1));
            ctrl_droplist(s, "Refuses all SSH-1 password camouflage", 's', 20,
                          HELPCTX(ssh_bugs_plainpw1),
                          sshbug_handler, I(CONF_sshbug_plainpw1));
            ctrl_droplist(s, "Chokes on SSH-1 RSA authentication", 'r', 20,
                          HELPCTX(ssh_bugs_rsa1),
                          sshbug_handler, I(CONF_sshbug_rsa1));
        }
    }

    if (DISPLAY_RECONFIGURABLE_PROTOCOL(PROT_SERIAL)) {
        const BackendVtable *ser_vt = backend_vt_from_proto(PROT_SERIAL);

        /*
         * The Connection/Serial panel.
         */
        ctrl_settitle(b, "Connection/Serial",
                      "Options controlling local serial lines");

        if (!midsession) {
            /*
             * We don't permit switching to a different serial port in
             * midflight, although we do allow all other
             * reconfiguration.
             */
            s = ctrl_getset(b, "Connection/Serial", "serline",
                            "Select a serial line");
            ctrl_editbox(s, "Serial line to connect to", 'l', 40,
                         HELPCTX(serial_line),
                         conf_editbox_handler, I(CONF_serline), ED_STR);
        }

        s = ctrl_getset(b, "Connection/Serial", "sercfg", "Configure the serial line");
        ctrl_editbox(s, "Speed (baud)", 's', 40,
                     HELPCTX(serial_speed),
                     conf_editbox_handler, I(CONF_serspeed), ED_INT);
        ctrl_editbox(s, "Data bits", 'b', 40,
                     HELPCTX(serial_databits),
                     conf_editbox_handler, I(CONF_serdatabits), ED_INT);
        /*
         * Stop bits come in units of one half.
         */
        static const struct conf_editbox_handler_type conf_editbox_stopbits = {
            .type = EDIT_FIXEDPOINT, .denominator = 2};

        ctrl_editbox(s, "Stop bits", 't', 40,
                     HELPCTX(serial_stopbits),
                     conf_editbox_handler, I(CONF_serstopbits),
                     CP(&conf_editbox_stopbits));
        ctrl_droplist(s, "Parity", 'p', 40,
                      HELPCTX(serial_parity), serial_parity_handler,
                      I(ser_vt->serial_parity_mask));
        ctrl_droplist(s, "Flow control", 'f', 40,
                      HELPCTX(serial_flow), serial_flow_handler,
                      I(ser_vt->serial_flow_mask));
    }

    if (DISPLAY_RECONFIGURABLE_PROTOCOL(PROT_TELNET)) {
        /*
         * The Connection/Telnet panel.
         */
        ctrl_settitle(b, "Connection/Telnet",
                      "Options controlling Telnet connections");

        s = ctrl_getset(b, "Connection/Telnet", "protocol",
                        "Telnet protocol adjustments");

        if (!midsession) {
            ctrl_radiobuttons(s, "Handling of OLD_ENVIRON ambiguity:",
                              NO_SHORTCUT, 2,
                              HELPCTX(telnet_oldenviron),
                              conf_radiobutton_bool_handler,
                              I(CONF_rfc_environ),
                              "BSD (commonplace)", 'b', I(false),
                              "RFC 1408 (unusual)", 'f', I(true));
            ctrl_radiobuttons(s, "Telnet negotiation mode:", 't', 2,
                              HELPCTX(telnet_passive),
                              conf_radiobutton_bool_handler,
                              I(CONF_passive_telnet),
                              "Passive", I(true), "Active", I(false));
        }
        ctrl_checkbox(s, "Keyboard sends Telnet special commands", 'k',
                      HELPCTX(telnet_specialkeys),
                      conf_checkbox_handler,
                      I(CONF_telnet_keyboard));
        ctrl_checkbox(s, "Return key sends Telnet New Line instead of ^M",
                      'm', HELPCTX(telnet_newline),
                      conf_checkbox_handler,
                      I(CONF_telnet_newline));
    }

    if (DISPLAY_NON_RECONFIGURABLE_PROTOCOL(PROT_RLOGIN)) {
        /*
         * The Connection/Rlogin panel.
         */
        ctrl_settitle(b, "Connection/Rlogin",
                      "Options controlling Rlogin connections");

        s = ctrl_getset(b, "Connection/Rlogin", "data",
                        "Data to send to the server");
        ctrl_editbox(s, "Local username:", 'l', 50,
                     HELPCTX(rlogin_localuser),
                     conf_editbox_handler, I(CONF_localusername), ED_STR);

    }

    if (DISPLAY_NON_RECONFIGURABLE_PROTOCOL(PROT_SUPDUP)) {
        /*
         * The Connection/SUPDUP panel.
         */
        ctrl_settitle(b, "Connection/SUPDUP",
                      "Options controlling SUPDUP connections");

        s = ctrl_getset(b, "Connection/SUPDUP", "main", NULL);

        ctrl_editbox(s, "Location string", 'l', 70,
                     HELPCTX(supdup_location),
                     conf_editbox_handler, I(CONF_supdup_location),
                     ED_STR);

        ctrl_radiobuttons(s, "Extended ASCII Character set:", 'e', 4,
                          HELPCTX(supdup_ascii),
                          conf_radiobutton_handler,
                          I(CONF_supdup_ascii_set),
                          "None", I(SUPDUP_CHARSET_ASCII),
                          "ITS", I(SUPDUP_CHARSET_ITS),
                          "WAITS", I(SUPDUP_CHARSET_WAITS));

        ctrl_checkbox(s, "**MORE** processing", 'm',
                      HELPCTX(supdup_more),
                      conf_checkbox_handler,
                      I(CONF_supdup_more));

        ctrl_checkbox(s, "Terminal scrolling", 's',
                      HELPCTX(supdup_scroll),
                      conf_checkbox_handler,
                      I(CONF_supdup_scroll));
    }
}