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- /*
- * Simplified MAC Kernel (smack) security module
- *
- * This file contains the smack hook function implementations.
- *
- * Authors:
- * Casey Schaufler <casey@schaufler-ca.com>
- * Jarkko Sakkinen <jarkko.sakkinen@intel.com>
- *
- * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
- * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
- * Paul Moore <paul@paul-moore.com>
- * Copyright (C) 2010 Nokia Corporation
- * Copyright (C) 2011 Intel Corporation.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2,
- * as published by the Free Software Foundation.
- */
- #include <linux/xattr.h>
- #include <linux/pagemap.h>
- #include <linux/mount.h>
- #include <linux/stat.h>
- #include <linux/kd.h>
- #include <asm/ioctls.h>
- #include <linux/ip.h>
- #include <linux/tcp.h>
- #include <linux/udp.h>
- #include <linux/slab.h>
- #include <linux/mutex.h>
- #include <linux/pipe_fs_i.h>
- #include <net/netlabel.h>
- #include <net/cipso_ipv4.h>
- #include <linux/audit.h>
- #include <linux/magic.h>
- #include <linux/dcache.h>
- #include <linux/personality.h>
- #include <linux/msg.h>
- #include <linux/shm.h>
- #include <linux/binfmts.h>
- #include "smack.h"
- #define TRANS_TRUE "TRUE"
- #define TRANS_TRUE_SIZE 4
- /**
- * smk_fetch - Fetch the smack label from a file.
- * @ip: a pointer to the inode
- * @dp: a pointer to the dentry
- *
- * Returns a pointer to the master list entry for the Smack label
- * or NULL if there was no label to fetch.
- */
- static char *smk_fetch(const char *name, struct inode *ip, struct dentry *dp)
- {
- int rc;
- char in[SMK_LABELLEN];
- if (ip->i_op->getxattr == NULL)
- return NULL;
- rc = ip->i_op->getxattr(dp, name, in, SMK_LABELLEN);
- if (rc < 0)
- return NULL;
- return smk_import(in, rc);
- }
- /**
- * new_inode_smack - allocate an inode security blob
- * @smack: a pointer to the Smack label to use in the blob
- *
- * Returns the new blob or NULL if there's no memory available
- */
- struct inode_smack *new_inode_smack(char *smack)
- {
- struct inode_smack *isp;
- isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL);
- if (isp == NULL)
- return NULL;
- isp->smk_inode = smack;
- isp->smk_flags = 0;
- mutex_init(&isp->smk_lock);
- return isp;
- }
- /**
- * new_task_smack - allocate a task security blob
- * @smack: a pointer to the Smack label to use in the blob
- *
- * Returns the new blob or NULL if there's no memory available
- */
- static struct task_smack *new_task_smack(char *task, char *forked, gfp_t gfp)
- {
- struct task_smack *tsp;
- tsp = kzalloc(sizeof(struct task_smack), gfp);
- if (tsp == NULL)
- return NULL;
- tsp->smk_task = task;
- tsp->smk_forked = forked;
- INIT_LIST_HEAD(&tsp->smk_rules);
- mutex_init(&tsp->smk_rules_lock);
- return tsp;
- }
- /**
- * smk_copy_rules - copy a rule set
- * @nhead - new rules header pointer
- * @ohead - old rules header pointer
- *
- * Returns 0 on success, -ENOMEM on error
- */
- static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
- gfp_t gfp)
- {
- struct smack_rule *nrp;
- struct smack_rule *orp;
- int rc = 0;
- INIT_LIST_HEAD(nhead);
- list_for_each_entry_rcu(orp, ohead, list) {
- nrp = kzalloc(sizeof(struct smack_rule), gfp);
- if (nrp == NULL) {
- rc = -ENOMEM;
- break;
- }
- *nrp = *orp;
- list_add_rcu(&nrp->list, nhead);
- }
- return rc;
- }
- /*
- * LSM hooks.
- * We he, that is fun!
- */
- /**
- * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
- * @ctp: child task pointer
- * @mode: ptrace attachment mode
- *
- * Returns 0 if access is OK, an error code otherwise
- *
- * Do the capability checks, and require read and write.
- */
- static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
- {
- int rc;
- struct smk_audit_info ad;
- char *tsp;
- rc = cap_ptrace_access_check(ctp, mode);
- if (rc != 0)
- return rc;
- tsp = smk_of_task_struct(ctp);
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
- smk_ad_setfield_u_tsk(&ad, ctp);
- rc = smk_curacc(tsp, MAY_READWRITE, &ad);
- return rc;
- }
- /**
- * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
- * @ptp: parent task pointer
- *
- * Returns 0 if access is OK, an error code otherwise
- *
- * Do the capability checks, and require read and write.
- */
- static int smack_ptrace_traceme(struct task_struct *ptp)
- {
- int rc;
- struct smk_audit_info ad;
- char *tsp;
- rc = cap_ptrace_traceme(ptp);
- if (rc != 0)
- return rc;
- tsp = smk_of_task_struct(ptp);
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
- smk_ad_setfield_u_tsk(&ad, ptp);
- rc = smk_curacc(tsp, MAY_READWRITE, &ad);
- return rc;
- }
- /**
- * smack_syslog - Smack approval on syslog
- * @type: message type
- *
- * Require that the task has the floor label
- *
- * Returns 0 on success, error code otherwise.
- */
- static int smack_syslog(int typefrom_file)
- {
- int rc = 0;
- char *sp = smk_of_current();
- if (capable(CAP_MAC_OVERRIDE))
- return 0;
- if (sp != smack_known_floor.smk_known)
- rc = -EACCES;
- return rc;
- }
- /*
- * Superblock Hooks.
- */
- /**
- * smack_sb_alloc_security - allocate a superblock blob
- * @sb: the superblock getting the blob
- *
- * Returns 0 on success or -ENOMEM on error.
- */
- static int smack_sb_alloc_security(struct super_block *sb)
- {
- struct superblock_smack *sbsp;
- sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
- if (sbsp == NULL)
- return -ENOMEM;
- sbsp->smk_root = smack_known_floor.smk_known;
- sbsp->smk_default = smack_known_floor.smk_known;
- sbsp->smk_floor = smack_known_floor.smk_known;
- sbsp->smk_hat = smack_known_hat.smk_known;
- sbsp->smk_initialized = 0;
- spin_lock_init(&sbsp->smk_sblock);
- sb->s_security = sbsp;
- return 0;
- }
- /**
- * smack_sb_free_security - free a superblock blob
- * @sb: the superblock getting the blob
- *
- */
- static void smack_sb_free_security(struct super_block *sb)
- {
- kfree(sb->s_security);
- sb->s_security = NULL;
- }
- /**
- * smack_sb_copy_data - copy mount options data for processing
- * @orig: where to start
- * @smackopts: mount options string
- *
- * Returns 0 on success or -ENOMEM on error.
- *
- * Copy the Smack specific mount options out of the mount
- * options list.
- */
- static int smack_sb_copy_data(char *orig, char *smackopts)
- {
- char *cp, *commap, *otheropts, *dp;
- otheropts = (char *)get_zeroed_page(GFP_KERNEL);
- if (otheropts == NULL)
- return -ENOMEM;
- for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
- if (strstr(cp, SMK_FSDEFAULT) == cp)
- dp = smackopts;
- else if (strstr(cp, SMK_FSFLOOR) == cp)
- dp = smackopts;
- else if (strstr(cp, SMK_FSHAT) == cp)
- dp = smackopts;
- else if (strstr(cp, SMK_FSROOT) == cp)
- dp = smackopts;
- else
- dp = otheropts;
- commap = strchr(cp, ',');
- if (commap != NULL)
- *commap = '\0';
- if (*dp != '\0')
- strcat(dp, ",");
- strcat(dp, cp);
- }
- strcpy(orig, otheropts);
- free_page((unsigned long)otheropts);
- return 0;
- }
- /**
- * smack_sb_kern_mount - Smack specific mount processing
- * @sb: the file system superblock
- * @flags: the mount flags
- * @data: the smack mount options
- *
- * Returns 0 on success, an error code on failure
- */
- static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
- {
- struct dentry *root = sb->s_root;
- struct inode *inode = root->d_inode;
- struct superblock_smack *sp = sb->s_security;
- struct inode_smack *isp;
- char *op;
- char *commap;
- char *nsp;
- spin_lock(&sp->smk_sblock);
- if (sp->smk_initialized != 0) {
- spin_unlock(&sp->smk_sblock);
- return 0;
- }
- sp->smk_initialized = 1;
- spin_unlock(&sp->smk_sblock);
- for (op = data; op != NULL; op = commap) {
- commap = strchr(op, ',');
- if (commap != NULL)
- *commap++ = '\0';
- if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) {
- op += strlen(SMK_FSHAT);
- nsp = smk_import(op, 0);
- if (nsp != NULL)
- sp->smk_hat = nsp;
- } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
- op += strlen(SMK_FSFLOOR);
- nsp = smk_import(op, 0);
- if (nsp != NULL)
- sp->smk_floor = nsp;
- } else if (strncmp(op, SMK_FSDEFAULT,
- strlen(SMK_FSDEFAULT)) == 0) {
- op += strlen(SMK_FSDEFAULT);
- nsp = smk_import(op, 0);
- if (nsp != NULL)
- sp->smk_default = nsp;
- } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
- op += strlen(SMK_FSROOT);
- nsp = smk_import(op, 0);
- if (nsp != NULL)
- sp->smk_root = nsp;
- }
- }
- /*
- * Initialize the root inode.
- */
- isp = inode->i_security;
- if (isp == NULL)
- inode->i_security = new_inode_smack(sp->smk_root);
- else
- isp->smk_inode = sp->smk_root;
- return 0;
- }
- /**
- * smack_sb_statfs - Smack check on statfs
- * @dentry: identifies the file system in question
- *
- * Returns 0 if current can read the floor of the filesystem,
- * and error code otherwise
- */
- static int smack_sb_statfs(struct dentry *dentry)
- {
- struct superblock_smack *sbp = dentry->d_sb->s_security;
- int rc;
- struct smk_audit_info ad;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
- smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
- rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
- return rc;
- }
- /**
- * smack_sb_mount - Smack check for mounting
- * @dev_name: unused
- * @path: mount point
- * @type: unused
- * @flags: unused
- * @data: unused
- *
- * Returns 0 if current can write the floor of the filesystem
- * being mounted on, an error code otherwise.
- */
- static int smack_sb_mount(const char *dev_name, struct path *path,
- const char *type, unsigned long flags, void *data)
- {
- struct superblock_smack *sbp = path->dentry->d_sb->s_security;
- struct smk_audit_info ad;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
- smk_ad_setfield_u_fs_path(&ad, *path);
- return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
- }
- /**
- * smack_sb_umount - Smack check for unmounting
- * @mnt: file system to unmount
- * @flags: unused
- *
- * Returns 0 if current can write the floor of the filesystem
- * being unmounted, an error code otherwise.
- */
- static int smack_sb_umount(struct vfsmount *mnt, int flags)
- {
- struct superblock_smack *sbp;
- struct smk_audit_info ad;
- struct path path;
- path.dentry = mnt->mnt_root;
- path.mnt = mnt;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
- smk_ad_setfield_u_fs_path(&ad, path);
- sbp = path.dentry->d_sb->s_security;
- return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
- }
- /*
- * BPRM hooks
- */
- /**
- * smack_bprm_set_creds - set creds for exec
- * @bprm: the exec information
- *
- * Returns 0 if it gets a blob, -ENOMEM otherwise
- */
- static int smack_bprm_set_creds(struct linux_binprm *bprm)
- {
- struct inode *inode = bprm->file->f_path.dentry->d_inode;
- struct task_smack *bsp = bprm->cred->security;
- struct inode_smack *isp;
- int rc;
- rc = cap_bprm_set_creds(bprm);
- if (rc != 0)
- return rc;
- if (bprm->cred_prepared)
- return 0;
- isp = inode->i_security;
- if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
- return 0;
- if (bprm->unsafe)
- return -EPERM;
- bsp->smk_task = isp->smk_task;
- bprm->per_clear |= PER_CLEAR_ON_SETID;
- return 0;
- }
- /**
- * smack_bprm_committing_creds - Prepare to install the new credentials
- * from bprm.
- *
- * @bprm: binprm for exec
- */
- static void smack_bprm_committing_creds(struct linux_binprm *bprm)
- {
- struct task_smack *bsp = bprm->cred->security;
- if (bsp->smk_task != bsp->smk_forked)
- current->pdeath_signal = 0;
- }
- /**
- * smack_bprm_secureexec - Return the decision to use secureexec.
- * @bprm: binprm for exec
- *
- * Returns 0 on success.
- */
- static int smack_bprm_secureexec(struct linux_binprm *bprm)
- {
- struct task_smack *tsp = current_security();
- int ret = cap_bprm_secureexec(bprm);
- if (!ret && (tsp->smk_task != tsp->smk_forked))
- ret = 1;
- return ret;
- }
- /*
- * Inode hooks
- */
- /**
- * smack_inode_alloc_security - allocate an inode blob
- * @inode: the inode in need of a blob
- *
- * Returns 0 if it gets a blob, -ENOMEM otherwise
- */
- static int smack_inode_alloc_security(struct inode *inode)
- {
- inode->i_security = new_inode_smack(smk_of_current());
- if (inode->i_security == NULL)
- return -ENOMEM;
- return 0;
- }
- /**
- * smack_inode_free_security - free an inode blob
- * @inode: the inode with a blob
- *
- * Clears the blob pointer in inode
- */
- static void smack_inode_free_security(struct inode *inode)
- {
- kfree(inode->i_security);
- inode->i_security = NULL;
- }
- /**
- * smack_inode_init_security - copy out the smack from an inode
- * @inode: the inode
- * @dir: unused
- * @qstr: unused
- * @name: where to put the attribute name
- * @value: where to put the attribute value
- * @len: where to put the length of the attribute
- *
- * Returns 0 if it all works out, -ENOMEM if there's no memory
- */
- static int smack_inode_init_security(struct inode *inode, struct inode *dir,
- const struct qstr *qstr, char **name,
- void **value, size_t *len)
- {
- struct smack_known *skp;
- char *csp = smk_of_current();
- char *isp = smk_of_inode(inode);
- char *dsp = smk_of_inode(dir);
- int may;
- if (name) {
- *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL);
- if (*name == NULL)
- return -ENOMEM;
- }
- if (value) {
- skp = smk_find_entry(csp);
- rcu_read_lock();
- may = smk_access_entry(csp, dsp, &skp->smk_rules);
- rcu_read_unlock();
- /*
- * If the access rule allows transmutation and
- * the directory requests transmutation then
- * by all means transmute.
- */
- if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
- smk_inode_transmutable(dir))
- isp = dsp;
- *value = kstrdup(isp, GFP_KERNEL);
- if (*value == NULL)
- return -ENOMEM;
- }
- if (len)
- *len = strlen(isp) + 1;
- return 0;
- }
- /**
- * smack_inode_link - Smack check on link
- * @old_dentry: the existing object
- * @dir: unused
- * @new_dentry: the new object
- *
- * Returns 0 if access is permitted, an error code otherwise
- */
- static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
- struct dentry *new_dentry)
- {
- char *isp;
- struct smk_audit_info ad;
- int rc;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
- smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
- isp = smk_of_inode(old_dentry->d_inode);
- rc = smk_curacc(isp, MAY_WRITE, &ad);
- if (rc == 0 && new_dentry->d_inode != NULL) {
- isp = smk_of_inode(new_dentry->d_inode);
- smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
- rc = smk_curacc(isp, MAY_WRITE, &ad);
- }
- return rc;
- }
- /**
- * smack_inode_unlink - Smack check on inode deletion
- * @dir: containing directory object
- * @dentry: file to unlink
- *
- * Returns 0 if current can write the containing directory
- * and the object, error code otherwise
- */
- static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
- {
- struct inode *ip = dentry->d_inode;
- struct smk_audit_info ad;
- int rc;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
- smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
- /*
- * You need write access to the thing you're unlinking
- */
- rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
- if (rc == 0) {
- /*
- * You also need write access to the containing directory
- */
- smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
- smk_ad_setfield_u_fs_inode(&ad, dir);
- rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
- }
- return rc;
- }
- /**
- * smack_inode_rmdir - Smack check on directory deletion
- * @dir: containing directory object
- * @dentry: directory to unlink
- *
- * Returns 0 if current can write the containing directory
- * and the directory, error code otherwise
- */
- static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
- {
- struct smk_audit_info ad;
- int rc;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
- smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
- /*
- * You need write access to the thing you're removing
- */
- rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
- if (rc == 0) {
- /*
- * You also need write access to the containing directory
- */
- smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
- smk_ad_setfield_u_fs_inode(&ad, dir);
- rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
- }
- return rc;
- }
- /**
- * smack_inode_rename - Smack check on rename
- * @old_inode: the old directory
- * @old_dentry: unused
- * @new_inode: the new directory
- * @new_dentry: unused
- *
- * Read and write access is required on both the old and
- * new directories.
- *
- * Returns 0 if access is permitted, an error code otherwise
- */
- static int smack_inode_rename(struct inode *old_inode,
- struct dentry *old_dentry,
- struct inode *new_inode,
- struct dentry *new_dentry)
- {
- int rc;
- char *isp;
- struct smk_audit_info ad;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
- smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
- isp = smk_of_inode(old_dentry->d_inode);
- rc = smk_curacc(isp, MAY_READWRITE, &ad);
- if (rc == 0 && new_dentry->d_inode != NULL) {
- isp = smk_of_inode(new_dentry->d_inode);
- smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
- rc = smk_curacc(isp, MAY_READWRITE, &ad);
- }
- return rc;
- }
- /**
- * smack_inode_permission - Smack version of permission()
- * @inode: the inode in question
- * @mask: the access requested
- *
- * This is the important Smack hook.
- *
- * Returns 0 if access is permitted, -EACCES otherwise
- */
- static int smack_inode_permission(struct inode *inode, int mask)
- {
- struct smk_audit_info ad;
- int no_block = mask & MAY_NOT_BLOCK;
- mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
- /*
- * No permission to check. Existence test. Yup, it's there.
- */
- if (mask == 0)
- return 0;
- /* May be droppable after audit */
- if (no_block)
- return -ECHILD;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
- smk_ad_setfield_u_fs_inode(&ad, inode);
- return smk_curacc(smk_of_inode(inode), mask, &ad);
- }
- /**
- * smack_inode_setattr - Smack check for setting attributes
- * @dentry: the object
- * @iattr: for the force flag
- *
- * Returns 0 if access is permitted, an error code otherwise
- */
- static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
- {
- struct smk_audit_info ad;
- /*
- * Need to allow for clearing the setuid bit.
- */
- if (iattr->ia_valid & ATTR_FORCE)
- return 0;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
- smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
- return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
- }
- /**
- * smack_inode_getattr - Smack check for getting attributes
- * @mnt: unused
- * @dentry: the object
- *
- * Returns 0 if access is permitted, an error code otherwise
- */
- static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
- {
- struct smk_audit_info ad;
- struct path path;
- path.dentry = dentry;
- path.mnt = mnt;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
- smk_ad_setfield_u_fs_path(&ad, path);
- return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
- }
- /**
- * smack_inode_setxattr - Smack check for setting xattrs
- * @dentry: the object
- * @name: name of the attribute
- * @value: unused
- * @size: unused
- * @flags: unused
- *
- * This protects the Smack attribute explicitly.
- *
- * Returns 0 if access is permitted, an error code otherwise
- */
- static int smack_inode_setxattr(struct dentry *dentry, const char *name,
- const void *value, size_t size, int flags)
- {
- struct smk_audit_info ad;
- int rc = 0;
- if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
- strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
- strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
- strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
- strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
- if (!capable(CAP_MAC_ADMIN))
- rc = -EPERM;
- /*
- * check label validity here so import wont fail on
- * post_setxattr
- */
- if (size == 0 || size >= SMK_LABELLEN ||
- smk_import(value, size) == NULL)
- rc = -EINVAL;
- } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
- if (!capable(CAP_MAC_ADMIN))
- rc = -EPERM;
- if (size != TRANS_TRUE_SIZE ||
- strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
- rc = -EINVAL;
- } else
- rc = cap_inode_setxattr(dentry, name, value, size, flags);
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
- smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
- if (rc == 0)
- rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
- return rc;
- }
- /**
- * smack_inode_post_setxattr - Apply the Smack update approved above
- * @dentry: object
- * @name: attribute name
- * @value: attribute value
- * @size: attribute size
- * @flags: unused
- *
- * Set the pointer in the inode blob to the entry found
- * in the master label list.
- */
- static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
- const void *value, size_t size, int flags)
- {
- char *nsp;
- struct inode_smack *isp = dentry->d_inode->i_security;
- if (strcmp(name, XATTR_NAME_SMACK) == 0) {
- nsp = smk_import(value, size);
- if (nsp != NULL)
- isp->smk_inode = nsp;
- else
- isp->smk_inode = smack_known_invalid.smk_known;
- } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
- nsp = smk_import(value, size);
- if (nsp != NULL)
- isp->smk_task = nsp;
- else
- isp->smk_task = smack_known_invalid.smk_known;
- } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
- nsp = smk_import(value, size);
- if (nsp != NULL)
- isp->smk_mmap = nsp;
- else
- isp->smk_mmap = smack_known_invalid.smk_known;
- } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
- isp->smk_flags |= SMK_INODE_TRANSMUTE;
- return;
- }
- /**
- * smack_inode_getxattr - Smack check on getxattr
- * @dentry: the object
- * @name: unused
- *
- * Returns 0 if access is permitted, an error code otherwise
- */
- static int smack_inode_getxattr(struct dentry *dentry, const char *name)
- {
- struct smk_audit_info ad;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
- smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
- return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
- }
- /**
- * smack_inode_removexattr - Smack check on removexattr
- * @dentry: the object
- * @name: name of the attribute
- *
- * Removing the Smack attribute requires CAP_MAC_ADMIN
- *
- * Returns 0 if access is permitted, an error code otherwise
- */
- static int smack_inode_removexattr(struct dentry *dentry, const char *name)
- {
- struct inode_smack *isp;
- struct smk_audit_info ad;
- int rc = 0;
- if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
- strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
- strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
- strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
- strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
- strcmp(name, XATTR_NAME_SMACKMMAP)) {
- if (!capable(CAP_MAC_ADMIN))
- rc = -EPERM;
- } else
- rc = cap_inode_removexattr(dentry, name);
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
- smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
- if (rc == 0)
- rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
- if (rc == 0) {
- isp = dentry->d_inode->i_security;
- isp->smk_task = NULL;
- isp->smk_mmap = NULL;
- }
- return rc;
- }
- /**
- * smack_inode_getsecurity - get smack xattrs
- * @inode: the object
- * @name: attribute name
- * @buffer: where to put the result
- * @alloc: unused
- *
- * Returns the size of the attribute or an error code
- */
- static int smack_inode_getsecurity(const struct inode *inode,
- const char *name, void **buffer,
- bool alloc)
- {
- struct socket_smack *ssp;
- struct socket *sock;
- struct super_block *sbp;
- struct inode *ip = (struct inode *)inode;
- char *isp;
- int ilen;
- int rc = 0;
- if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
- isp = smk_of_inode(inode);
- ilen = strlen(isp) + 1;
- *buffer = isp;
- return ilen;
- }
- /*
- * The rest of the Smack xattrs are only on sockets.
- */
- sbp = ip->i_sb;
- if (sbp->s_magic != SOCKFS_MAGIC)
- return -EOPNOTSUPP;
- sock = SOCKET_I(ip);
- if (sock == NULL || sock->sk == NULL)
- return -EOPNOTSUPP;
- ssp = sock->sk->sk_security;
- if (strcmp(name, XATTR_SMACK_IPIN) == 0)
- isp = ssp->smk_in;
- else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
- isp = ssp->smk_out;
- else
- return -EOPNOTSUPP;
- ilen = strlen(isp) + 1;
- if (rc == 0) {
- *buffer = isp;
- rc = ilen;
- }
- return rc;
- }
- /**
- * smack_inode_listsecurity - list the Smack attributes
- * @inode: the object
- * @buffer: where they go
- * @buffer_size: size of buffer
- *
- * Returns 0 on success, -EINVAL otherwise
- */
- static int smack_inode_listsecurity(struct inode *inode, char *buffer,
- size_t buffer_size)
- {
- int len = strlen(XATTR_NAME_SMACK);
- if (buffer != NULL && len <= buffer_size) {
- memcpy(buffer, XATTR_NAME_SMACK, len);
- return len;
- }
- return -EINVAL;
- }
- /**
- * smack_inode_getsecid - Extract inode's security id
- * @inode: inode to extract the info from
- * @secid: where result will be saved
- */
- static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
- {
- struct inode_smack *isp = inode->i_security;
- *secid = smack_to_secid(isp->smk_inode);
- }
- /*
- * File Hooks
- */
- /**
- * smack_file_permission - Smack check on file operations
- * @file: unused
- * @mask: unused
- *
- * Returns 0
- *
- * Should access checks be done on each read or write?
- * UNICOS and SELinux say yes.
- * Trusted Solaris, Trusted Irix, and just about everyone else says no.
- *
- * I'll say no for now. Smack does not do the frequent
- * label changing that SELinux does.
- */
- static int smack_file_permission(struct file *file, int mask)
- {
- return 0;
- }
- /**
- * smack_file_alloc_security - assign a file security blob
- * @file: the object
- *
- * The security blob for a file is a pointer to the master
- * label list, so no allocation is done.
- *
- * Returns 0
- */
- static int smack_file_alloc_security(struct file *file)
- {
- file->f_security = smk_of_current();
- return 0;
- }
- /**
- * smack_file_free_security - clear a file security blob
- * @file: the object
- *
- * The security blob for a file is a pointer to the master
- * label list, so no memory is freed.
- */
- static void smack_file_free_security(struct file *file)
- {
- file->f_security = NULL;
- }
- /**
- * smack_file_ioctl - Smack check on ioctls
- * @file: the object
- * @cmd: what to do
- * @arg: unused
- *
- * Relies heavily on the correct use of the ioctl command conventions.
- *
- * Returns 0 if allowed, error code otherwise
- */
- static int smack_file_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
- {
- int rc = 0;
- struct smk_audit_info ad;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
- smk_ad_setfield_u_fs_path(&ad, file->f_path);
- if (_IOC_DIR(cmd) & _IOC_WRITE)
- rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
- if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
- rc = smk_curacc(file->f_security, MAY_READ, &ad);
- return rc;
- }
- /**
- * smack_file_lock - Smack check on file locking
- * @file: the object
- * @cmd: unused
- *
- * Returns 0 if current has write access, error code otherwise
- */
- static int smack_file_lock(struct file *file, unsigned int cmd)
- {
- struct smk_audit_info ad;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
- smk_ad_setfield_u_fs_path(&ad, file->f_path);
- return smk_curacc(file->f_security, MAY_WRITE, &ad);
- }
- /**
- * smack_file_fcntl - Smack check on fcntl
- * @file: the object
- * @cmd: what action to check
- * @arg: unused
- *
- * Generally these operations are harmless.
- * File locking operations present an obvious mechanism
- * for passing information, so they require write access.
- *
- * Returns 0 if current has access, error code otherwise
- */
- static int smack_file_fcntl(struct file *file, unsigned int cmd,
- unsigned long arg)
- {
- struct smk_audit_info ad;
- int rc = 0;
- switch (cmd) {
- case F_GETLK:
- case F_SETLK:
- case F_SETLKW:
- case F_SETOWN:
- case F_SETSIG:
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
- smk_ad_setfield_u_fs_path(&ad, file->f_path);
- rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
- break;
- default:
- break;
- }
- return rc;
- }
- /**
- * smack_file_mmap :
- * Check permissions for a mmap operation. The @file may be NULL, e.g.
- * if mapping anonymous memory.
- * @file contains the file structure for file to map (may be NULL).
- * @reqprot contains the protection requested by the application.
- * @prot contains the protection that will be applied by the kernel.
- * @flags contains the operational flags.
- * Return 0 if permission is granted.
- */
- static int smack_file_mmap(struct file *file,
- unsigned long reqprot, unsigned long prot,
- unsigned long flags, unsigned long addr,
- unsigned long addr_only)
- {
- struct smack_known *skp;
- struct smack_rule *srp;
- struct task_smack *tsp;
- char *sp;
- char *msmack;
- char *osmack;
- struct inode_smack *isp;
- struct dentry *dp;
- int may;
- int mmay;
- int tmay;
- int rc;
- /* do DAC check on address space usage */
- rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
- if (rc || addr_only)
- return rc;
- if (file == NULL || file->f_dentry == NULL)
- return 0;
- dp = file->f_dentry;
- if (dp->d_inode == NULL)
- return 0;
- isp = dp->d_inode->i_security;
- if (isp->smk_mmap == NULL)
- return 0;
- msmack = isp->smk_mmap;
- tsp = current_security();
- sp = smk_of_current();
- skp = smk_find_entry(sp);
- rc = 0;
- rcu_read_lock();
- /*
- * For each Smack rule associated with the subject
- * label verify that the SMACK64MMAP also has access
- * to that rule's object label.
- */
- list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
- osmack = srp->smk_object;
- /*
- * Matching labels always allows access.
- */
- if (msmack == osmack)
- continue;
- /*
- * If there is a matching local rule take
- * that into account as well.
- */
- may = smk_access_entry(srp->smk_subject, osmack,
- &tsp->smk_rules);
- if (may == -ENOENT)
- may = srp->smk_access;
- else
- may &= srp->smk_access;
- /*
- * If may is zero the SMACK64MMAP subject can't
- * possibly have less access.
- */
- if (may == 0)
- continue;
- /*
- * Fetch the global list entry.
- * If there isn't one a SMACK64MMAP subject
- * can't have as much access as current.
- */
- skp = smk_find_entry(msmack);
- mmay = smk_access_entry(msmack, osmack, &skp->smk_rules);
- if (mmay == -ENOENT) {
- rc = -EACCES;
- break;
- }
- /*
- * If there is a local entry it modifies the
- * potential access, too.
- */
- tmay = smk_access_entry(msmack, osmack, &tsp->smk_rules);
- if (tmay != -ENOENT)
- mmay &= tmay;
- /*
- * If there is any access available to current that is
- * not available to a SMACK64MMAP subject
- * deny access.
- */
- if ((may | mmay) != mmay) {
- rc = -EACCES;
- break;
- }
- }
- rcu_read_unlock();
- return rc;
- }
- /**
- * smack_file_set_fowner - set the file security blob value
- * @file: object in question
- *
- * Returns 0
- * Further research may be required on this one.
- */
- static int smack_file_set_fowner(struct file *file)
- {
- file->f_security = smk_of_current();
- return 0;
- }
- /**
- * smack_file_send_sigiotask - Smack on sigio
- * @tsk: The target task
- * @fown: the object the signal come from
- * @signum: unused
- *
- * Allow a privileged task to get signals even if it shouldn't
- *
- * Returns 0 if a subject with the object's smack could
- * write to the task, an error code otherwise.
- */
- static int smack_file_send_sigiotask(struct task_struct *tsk,
- struct fown_struct *fown, int signum)
- {
- struct file *file;
- int rc;
- char *tsp = smk_of_task(tsk->cred->security);
- struct smk_audit_info ad;
- /*
- * struct fown_struct is never outside the context of a struct file
- */
- file = container_of(fown, struct file, f_owner);
- /* we don't log here as rc can be overriden */
- rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL);
- if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
- rc = 0;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
- smk_ad_setfield_u_tsk(&ad, tsk);
- smack_log(file->f_security, tsp, MAY_WRITE, rc, &ad);
- return rc;
- }
- /**
- * smack_file_receive - Smack file receive check
- * @file: the object
- *
- * Returns 0 if current has access, error code otherwise
- */
- static int smack_file_receive(struct file *file)
- {
- int may = 0;
- struct smk_audit_info ad;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
- smk_ad_setfield_u_fs_path(&ad, file->f_path);
- /*
- * This code relies on bitmasks.
- */
- if (file->f_mode & FMODE_READ)
- may = MAY_READ;
- if (file->f_mode & FMODE_WRITE)
- may |= MAY_WRITE;
- return smk_curacc(file->f_security, may, &ad);
- }
- /**
- * smack_dentry_open - Smack dentry open processing
- * @file: the object
- * @cred: unused
- *
- * Set the security blob in the file structure.
- *
- * Returns 0
- */
- static int smack_dentry_open(struct file *file, const struct cred *cred)
- {
- struct inode_smack *isp = file->f_path.dentry->d_inode->i_security;
- file->f_security = isp->smk_inode;
- return 0;
- }
- /*
- * Task hooks
- */
- /**
- * smack_cred_alloc_blank - "allocate" blank task-level security credentials
- * @new: the new credentials
- * @gfp: the atomicity of any memory allocations
- *
- * Prepare a blank set of credentials for modification. This must allocate all
- * the memory the LSM module might require such that cred_transfer() can
- * complete without error.
- */
- static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
- {
- struct task_smack *tsp;
- tsp = new_task_smack(NULL, NULL, gfp);
- if (tsp == NULL)
- return -ENOMEM;
- cred->security = tsp;
- return 0;
- }
- /**
- * smack_cred_free - "free" task-level security credentials
- * @cred: the credentials in question
- *
- */
- static void smack_cred_free(struct cred *cred)
- {
- struct task_smack *tsp = cred->security;
- struct smack_rule *rp;
- struct list_head *l;
- struct list_head *n;
- if (tsp == NULL)
- return;
- cred->security = NULL;
- list_for_each_safe(l, n, &tsp->smk_rules) {
- rp = list_entry(l, struct smack_rule, list);
- list_del(&rp->list);
- kfree(rp);
- }
- kfree(tsp);
- }
- /**
- * smack_cred_prepare - prepare new set of credentials for modification
- * @new: the new credentials
- * @old: the original credentials
- * @gfp: the atomicity of any memory allocations
- *
- * Prepare a new set of credentials for modification.
- */
- static int smack_cred_prepare(struct cred *new, const struct cred *old,
- gfp_t gfp)
- {
- struct task_smack *old_tsp = old->security;
- struct task_smack *new_tsp;
- int rc;
- new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
- if (new_tsp == NULL)
- return -ENOMEM;
- rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
- if (rc != 0)
- return rc;
- new->security = new_tsp;
- return 0;
- }
- /**
- * smack_cred_transfer - Transfer the old credentials to the new credentials
- * @new: the new credentials
- * @old: the original credentials
- *
- * Fill in a set of blank credentials from another set of credentials.
- */
- static void smack_cred_transfer(struct cred *new, const struct cred *old)
- {
- struct task_smack *old_tsp = old->security;
- struct task_smack *new_tsp = new->security;
- new_tsp->smk_task = old_tsp->smk_task;
- new_tsp->smk_forked = old_tsp->smk_task;
- mutex_init(&new_tsp->smk_rules_lock);
- INIT_LIST_HEAD(&new_tsp->smk_rules);
- /* cbs copy rule list */
- }
- /**
- * smack_kernel_act_as - Set the subjective context in a set of credentials
- * @new: points to the set of credentials to be modified.
- * @secid: specifies the security ID to be set
- *
- * Set the security data for a kernel service.
- */
- static int smack_kernel_act_as(struct cred *new, u32 secid)
- {
- struct task_smack *new_tsp = new->security;
- char *smack = smack_from_secid(secid);
- if (smack == NULL)
- return -EINVAL;
- new_tsp->smk_task = smack;
- return 0;
- }
- /**
- * smack_kernel_create_files_as - Set the file creation label in a set of creds
- * @new: points to the set of credentials to be modified
- * @inode: points to the inode to use as a reference
- *
- * Set the file creation context in a set of credentials to the same
- * as the objective context of the specified inode
- */
- static int smack_kernel_create_files_as(struct cred *new,
- struct inode *inode)
- {
- struct inode_smack *isp = inode->i_security;
- struct task_smack *tsp = new->security;
- tsp->smk_forked = isp->smk_inode;
- tsp->smk_task = isp->smk_inode;
- return 0;
- }
- /**
- * smk_curacc_on_task - helper to log task related access
- * @p: the task object
- * @access: the access requested
- * @caller: name of the calling function for audit
- *
- * Return 0 if access is permitted
- */
- static int smk_curacc_on_task(struct task_struct *p, int access,
- const char *caller)
- {
- struct smk_audit_info ad;
- smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
- smk_ad_setfield_u_tsk(&ad, p);
- return smk_curacc(smk_of_task_struct(p), access, &ad);
- }
- /**
- * smack_task_setpgid - Smack check on setting pgid
- * @p: the task object
- * @pgid: unused
- *
- * Return 0 if write access is permitted
- */
- static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
- {
- return smk_curacc_on_task(p, MAY_WRITE, __func__);
- }
- /**
- * smack_task_getpgid - Smack access check for getpgid
- * @p: the object task
- *
- * Returns 0 if current can read the object task, error code otherwise
- */
- static int smack_task_getpgid(struct task_struct *p)
- {
- return smk_curacc_on_task(p, MAY_READ, __func__);
- }
- /**
- * smack_task_getsid - Smack access check for getsid
- * @p: the object task
- *
- * Returns 0 if current can read the object task, error code otherwise
- */
- static int smack_task_getsid(struct task_struct *p)
- {
- return smk_curacc_on_task(p, MAY_READ, __func__);
- }
- /**
- * smack_task_getsecid - get the secid of the task
- * @p: the object task
- * @secid: where to put the result
- *
- * Sets the secid to contain a u32 version of the smack label.
- */
- static void smack_task_getsecid(struct task_struct *p, u32 *secid)
- {
- *secid = smack_to_secid(smk_of_task_struct(p));
- }
- /**
- * smack_task_setnice - Smack check on setting nice
- * @p: the task object
- * @nice: unused
- *
- * Return 0 if write access is permitted
- */
- static int smack_task_setnice(struct task_struct *p, int nice)
- {
- int rc;
- rc = cap_task_setnice(p, nice);
- if (rc == 0)
- rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
- return rc;
- }
- /**
- * smack_task_setioprio - Smack check on setting ioprio
- * @p: the task object
- * @ioprio: unused
- *
- * Return 0 if write access is permitted
- */
- static int smack_task_setioprio(struct task_struct *p, int ioprio)
- {
- int rc;
- rc = cap_task_setioprio(p, ioprio);
- if (rc == 0)
- rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
- return rc;
- }
- /**
- * smack_task_getioprio - Smack check on reading ioprio
- * @p: the task object
- *
- * Return 0 if read access is permitted
- */
- static int smack_task_getioprio(struct task_struct *p)
- {
- return smk_curacc_on_task(p, MAY_READ, __func__);
- }
- /**
- * smack_task_setscheduler - Smack check on setting scheduler
- * @p: the task object
- * @policy: unused
- * @lp: unused
- *
- * Return 0 if read access is permitted
- */
- static int smack_task_setscheduler(struct task_struct *p)
- {
- int rc;
- rc = cap_task_setscheduler(p);
- if (rc == 0)
- rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
- return rc;
- }
- /**
- * smack_task_getscheduler - Smack check on reading scheduler
- * @p: the task object
- *
- * Return 0 if read access is permitted
- */
- static int smack_task_getscheduler(struct task_struct *p)
- {
- return smk_curacc_on_task(p, MAY_READ, __func__);
- }
- /**
- * smack_task_movememory - Smack check on moving memory
- * @p: the task object
- *
- * Return 0 if write access is permitted
- */
- static int smack_task_movememory(struct task_struct *p)
- {
- return smk_curacc_on_task(p, MAY_WRITE, __func__);
- }
- /**
- * smack_task_kill - Smack check on signal delivery
- * @p: the task object
- * @info: unused
- * @sig: unused
- * @secid: identifies the smack to use in lieu of current's
- *
- * Return 0 if write access is permitted
- *
- * The secid behavior is an artifact of an SELinux hack
- * in the USB code. Someday it may go away.
- */
- static int smack_task_kill(struct task_struct *p, struct siginfo *info,
- int sig, u32 secid)
- {
- struct smk_audit_info ad;
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
- smk_ad_setfield_u_tsk(&ad, p);
- /*
- * Sending a signal requires that the sender
- * can write the receiver.
- */
- if (secid == 0)
- return smk_curacc(smk_of_task_struct(p), MAY_WRITE,
- &ad);
- /*
- * If the secid isn't 0 we're dealing with some USB IO
- * specific behavior. This is not clean. For one thing
- * we can't take privilege into account.
- */
- return smk_access(smack_from_secid(secid),
- smk_of_task_struct(p), MAY_WRITE, &ad);
- }
- /**
- * smack_task_wait - Smack access check for waiting
- * @p: task to wait for
- *
- * Returns 0 if current can wait for p, error code otherwise
- */
- static int smack_task_wait(struct task_struct *p)
- {
- struct smk_audit_info ad;
- char *sp = smk_of_current();
- char *tsp;
- int rc;
- rcu_read_lock();
- tsp = smk_of_forked(__task_cred(p)->security);
- rcu_read_unlock();
- /* we don't log here, we can be overriden */
- rc = smk_access(tsp, sp, MAY_WRITE, NULL);
- if (rc == 0)
- goto out_log;
- /*
- * Allow the operation to succeed if either task
- * has privilege to perform operations that might
- * account for the smack labels having gotten to
- * be different in the first place.
- *
- * This breaks the strict subject/object access
- * control ideal, taking the object's privilege
- * state into account in the decision as well as
- * the smack value.
- */
- if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
- rc = 0;
- /* we log only if we didn't get overriden */
- out_log:
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
- smk_ad_setfield_u_tsk(&ad, p);
- smack_log(tsp, sp, MAY_WRITE, rc, &ad);
- return rc;
- }
- /**
- * smack_task_to_inode - copy task smack into the inode blob
- * @p: task to copy from
- * @inode: inode to copy to
- *
- * Sets the smack pointer in the inode security blob
- */
- static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
- {
- struct inode_smack *isp = inode->i_security;
- isp->smk_inode = smk_of_task_struct(p);
- }
- /*
- * Socket hooks.
- */
- /**
- * smack_sk_alloc_security - Allocate a socket blob
- * @sk: the socket
- * @family: unused
- * @gfp_flags: memory allocation flags
- *
- * Assign Smack pointers to current
- *
- * Returns 0 on success, -ENOMEM is there's no memory
- */
- static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
- {
- char *csp = smk_of_current();
- struct socket_smack *ssp;
- ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
- if (ssp == NULL)
- return -ENOMEM;
- ssp->smk_in = csp;
- ssp->smk_out = csp;
- ssp->smk_packet = NULL;
- sk->sk_security = ssp;
- return 0;
- }
- /**
- * smack_sk_free_security - Free a socket blob
- * @sk: the socket
- *
- * Clears the blob pointer
- */
- static void smack_sk_free_security(struct sock *sk)
- {
- kfree(sk->sk_security);
- }
- /**
- * smack_host_label - check host based restrictions
- * @sip: the object end
- *
- * looks for host based access restrictions
- *
- * This version will only be appropriate for really small sets of single label
- * hosts. The caller is responsible for ensuring that the RCU read lock is
- * taken before calling this function.
- *
- * Returns the label of the far end or NULL if it's not special.
- */
- static char *smack_host_label(struct sockaddr_in *sip)
- {
- struct smk_netlbladdr *snp;
- struct in_addr *siap = &sip->sin_addr;
- if (siap->s_addr == 0)
- return NULL;
- list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list)
- /*
- * we break after finding the first match because
- * the list is sorted from longest to shortest mask
- * so we have found the most specific match
- */
- if ((&snp->smk_host.sin_addr)->s_addr ==
- (siap->s_addr & (&snp->smk_mask)->s_addr)) {
- /* we have found the special CIPSO option */
- if (snp->smk_label == smack_cipso_option)
- return NULL;
- return snp->smk_label;
- }
- return NULL;
- }
- /**
- * smack_set_catset - convert a capset to netlabel mls categories
- * @catset: the Smack categories
- * @sap: where to put the netlabel categories
- *
- * Allocates and fills attr.mls.cat
- */
- static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
- {
- unsigned char *cp;
- unsigned char m;
- int cat;
- int rc;
- int byte;
- if (!catset)
- return;
- sap->flags |= NETLBL_SECATTR_MLS_CAT;
- sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
- sap->attr.mls.cat->startbit = 0;
- for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
- for (m = 0x80; m != 0; m >>= 1, cat++) {
- if ((m & *cp) == 0)
- continue;
- rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
- cat, GFP_ATOMIC);
- }
- }
- /**
- * smack_to_secattr - fill a secattr from a smack value
- * @smack: the smack value
- * @nlsp: where the result goes
- *
- * Casey says that CIPSO is good enough for now.
- * It can be used to effect.
- * It can also be abused to effect when necessary.
- * Apologies to the TSIG group in general and GW in particular.
- */
- static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
- {
- struct smack_cipso cipso;
- int rc;
- nlsp->domain = smack;
- nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
- rc = smack_to_cipso(smack, &cipso);
- if (rc == 0) {
- nlsp->attr.mls.lvl = cipso.smk_level;
- smack_set_catset(cipso.smk_catset, nlsp);
- } else {
- nlsp->attr.mls.lvl = smack_cipso_direct;
- smack_set_catset(smack, nlsp);
- }
- }
- /**
- * smack_netlabel - Set the secattr on a socket
- * @sk: the socket
- * @labeled: socket label scheme
- *
- * Convert the outbound smack value (smk_out) to a
- * secattr and attach it to the socket.
- *
- * Returns 0 on success or an error code
- */
- static int smack_netlabel(struct sock *sk, int labeled)
- {
- struct socket_smack *ssp = sk->sk_security;
- struct netlbl_lsm_secattr secattr;
- int rc = 0;
- /*
- * Usually the netlabel code will handle changing the
- * packet labeling based on the label.
- * The case of a single label host is different, because
- * a single label host should never get a labeled packet
- * even though the label is usually associated with a packet
- * label.
- */
- local_bh_disable();
- bh_lock_sock_nested(sk);
- if (ssp->smk_out == smack_net_ambient ||
- labeled == SMACK_UNLABELED_SOCKET)
- netlbl_sock_delattr(sk);
- else {
- netlbl_secattr_init(&secattr);
- smack_to_secattr(ssp->smk_out, &secattr);
- rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr);
- netlbl_secattr_destroy(&secattr);
- }
- bh_unlock_sock(sk);
- local_bh_enable();
- return rc;
- }
- /**
- * smack_netlbel_send - Set the secattr on a socket and perform access checks
- * @sk: the socket
- * @sap: the destination address
- *
- * Set the correct secattr for the given socket based on the destination
- * address and perform any outbound access checks needed.
- *
- * Returns 0 on success or an error code.
- *
- */
- static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
- {
- int rc;
- int sk_lbl;
- char *hostsp;
- struct socket_smack *ssp = sk->sk_security;
- struct smk_audit_info ad;
- rcu_read_lock();
- hostsp = smack_host_label(sap);
- if (hostsp != NULL) {
- #ifdef CONFIG_AUDIT
- struct lsm_network_audit net;
- smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
- ad.a.u.net->family = sap->sin_family;
- ad.a.u.net->dport = sap->sin_port;
- ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
- #endif
- sk_lbl = SMACK_UNLABELED_SOCKET;
- rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad);
- } else {
- sk_lbl = SMACK_CIPSO_SOCKET;
- rc = 0;
- }
- rcu_read_unlock();
- if (rc != 0)
- return rc;
- return smack_netlabel(sk, sk_lbl);
- }
- /**
- * smack_inode_setsecurity - set smack xattrs
- * @inode: the object
- * @name: attribute name
- * @value: attribute value
- * @size: size of the attribute
- * @flags: unused
- *
- * Sets the named attribute in the appropriate blob
- *
- * Returns 0 on success, or an error code
- */
- static int smack_inode_setsecurity(struct inode *inode, const char *name,
- const void *value, size_t size, int flags)
- {
- char *sp;
- struct inode_smack *nsp = inode->i_security;
- struct socket_smack *ssp;
- struct socket *sock;
- int rc = 0;
- if (value == NULL || size > SMK_LABELLEN || size == 0)
- return -EACCES;
- sp = smk_import(value, size);
- if (sp == NULL)
- return -EINVAL;
- if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
- nsp->smk_inode = sp;
- nsp->smk_flags |= SMK_INODE_INSTANT;
- return 0;
- }
- /*
- * The rest of the Smack xattrs are only on sockets.
- */
- if (inode->i_sb->s_magic != SOCKFS_MAGIC)
- return -EOPNOTSUPP;
- sock = SOCKET_I(inode);
- if (sock == NULL || sock->sk == NULL)
- return -EOPNOTSUPP;
- ssp = sock->sk->sk_security;
- if (strcmp(name, XATTR_SMACK_IPIN) == 0)
- ssp->smk_in = sp;
- else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
- ssp->smk_out = sp;
- if (sock->sk->sk_family != PF_UNIX) {
- rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
- if (rc != 0)
- printk(KERN_WARNING
- "Smack: \"%s\" netlbl error %d.\n",
- __func__, -rc);
- }
- } else
- return -EOPNOTSUPP;
- return 0;
- }
- /**
- * smack_socket_post_create - finish socket setup
- * @sock: the socket
- * @family: protocol family
- * @type: unused
- * @protocol: unused
- * @kern: unused
- *
- * Sets the netlabel information on the socket
- *
- * Returns 0 on success, and error code otherwise
- */
- static int smack_socket_post_create(struct socket *sock, int family,
- int type, int protocol, int kern)
- {
- if (family != PF_INET || sock->sk == NULL)
- return 0;
- /*
- * Set the outbound netlbl.
- */
- return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
- }
- /**
- * smack_socket_connect - connect access check
- * @sock: the socket
- * @sap: the other end
- * @addrlen: size of sap
- *
- * Verifies that a connection may be possible
- *
- * Returns 0 on success, and error code otherwise
- */
- static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
- int addrlen)
- {
- if (sock->sk == NULL || sock->sk->sk_family != PF_INET)
- return 0;
- if (addrlen < sizeof(struct sockaddr_in))
- return -EINVAL;
- return smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
- }
- /**
- * smack_flags_to_may - convert S_ to MAY_ values
- * @flags: the S_ value
- *
- * Returns the equivalent MAY_ value
- */
- static int smack_flags_to_may(int flags)
- {
- int may = 0;
- if (flags & S_IRUGO)
- may |= MAY_READ;
- if (flags & S_IWUGO)
- may |= MAY_WRITE;
- if (flags & S_IXUGO)
- may |= MAY_EXEC;
- return may;
- }
- /**
- * smack_msg_msg_alloc_security - Set the security blob for msg_msg
- * @msg: the object
- *
- * Returns 0
- */
- static int smack_msg_msg_alloc_security(struct msg_msg *msg)
- {
- msg->security = smk_of_current();
- return 0;
- }
- /**
- * smack_msg_msg_free_security - Clear the security blob for msg_msg
- * @msg: the object
- *
- * Clears the blob pointer
- */
- static void smack_msg_msg_free_security(struct msg_msg *msg)
- {
- msg->security = NULL;
- }
- /**
- * smack_of_shm - the smack pointer for the shm
- * @shp: the object
- *
- * Returns a pointer to the smack value
- */
- static char *smack_of_shm(struct shmid_kernel *shp)
- {
- return (char *)shp->shm_perm.security;
- }
- /**
- * smack_shm_alloc_security - Set the security blob for shm
- * @shp: the object
- *
- * Returns 0
- */
- static int smack_shm_alloc_security(struct shmid_kernel *shp)
- {
- struct kern_ipc_perm *isp = &shp->shm_perm;
- isp->security = smk_of_current();
- return 0;
- }
- /**
- * smack_shm_free_security - Clear the security blob for shm
- * @shp: the object
- *
- * Clears the blob pointer
- */
- static void smack_shm_free_security(struct shmid_kernel *shp)
- {
- struct kern_ipc_perm *isp = &shp->shm_perm;
- isp->security = NULL;
- }
- /**
- * smk_curacc_shm : check if current has access on shm
- * @shp : the object
- * @access : access requested
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smk_curacc_shm(struct shmid_kernel *shp, int access)
- {
- char *ssp = smack_of_shm(shp);
- struct smk_audit_info ad;
- #ifdef CONFIG_AUDIT
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
- ad.a.u.ipc_id = shp->shm_perm.id;
- #endif
- return smk_curacc(ssp, access, &ad);
- }
- /**
- * smack_shm_associate - Smack access check for shm
- * @shp: the object
- * @shmflg: access requested
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
- {
- int may;
- may = smack_flags_to_may(shmflg);
- return smk_curacc_shm(shp, may);
- }
- /**
- * smack_shm_shmctl - Smack access check for shm
- * @shp: the object
- * @cmd: what it wants to do
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
- {
- int may;
- switch (cmd) {
- case IPC_STAT:
- case SHM_STAT:
- may = MAY_READ;
- break;
- case IPC_SET:
- case SHM_LOCK:
- case SHM_UNLOCK:
- case IPC_RMID:
- may = MAY_READWRITE;
- break;
- case IPC_INFO:
- case SHM_INFO:
- /*
- * System level information.
- */
- return 0;
- default:
- return -EINVAL;
- }
- return smk_curacc_shm(shp, may);
- }
- /**
- * smack_shm_shmat - Smack access for shmat
- * @shp: the object
- * @shmaddr: unused
- * @shmflg: access requested
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
- int shmflg)
- {
- int may;
- may = smack_flags_to_may(shmflg);
- return smk_curacc_shm(shp, may);
- }
- /**
- * smack_of_sem - the smack pointer for the sem
- * @sma: the object
- *
- * Returns a pointer to the smack value
- */
- static char *smack_of_sem(struct sem_array *sma)
- {
- return (char *)sma->sem_perm.security;
- }
- /**
- * smack_sem_alloc_security - Set the security blob for sem
- * @sma: the object
- *
- * Returns 0
- */
- static int smack_sem_alloc_security(struct sem_array *sma)
- {
- struct kern_ipc_perm *isp = &sma->sem_perm;
- isp->security = smk_of_current();
- return 0;
- }
- /**
- * smack_sem_free_security - Clear the security blob for sem
- * @sma: the object
- *
- * Clears the blob pointer
- */
- static void smack_sem_free_security(struct sem_array *sma)
- {
- struct kern_ipc_perm *isp = &sma->sem_perm;
- isp->security = NULL;
- }
- /**
- * smk_curacc_sem : check if current has access on sem
- * @sma : the object
- * @access : access requested
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smk_curacc_sem(struct sem_array *sma, int access)
- {
- char *ssp = smack_of_sem(sma);
- struct smk_audit_info ad;
- #ifdef CONFIG_AUDIT
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
- ad.a.u.ipc_id = sma->sem_perm.id;
- #endif
- return smk_curacc(ssp, access, &ad);
- }
- /**
- * smack_sem_associate - Smack access check for sem
- * @sma: the object
- * @semflg: access requested
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smack_sem_associate(struct sem_array *sma, int semflg)
- {
- int may;
- may = smack_flags_to_may(semflg);
- return smk_curacc_sem(sma, may);
- }
- /**
- * smack_sem_shmctl - Smack access check for sem
- * @sma: the object
- * @cmd: what it wants to do
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smack_sem_semctl(struct sem_array *sma, int cmd)
- {
- int may;
- switch (cmd) {
- case GETPID:
- case GETNCNT:
- case GETZCNT:
- case GETVAL:
- case GETALL:
- case IPC_STAT:
- case SEM_STAT:
- may = MAY_READ;
- break;
- case SETVAL:
- case SETALL:
- case IPC_RMID:
- case IPC_SET:
- may = MAY_READWRITE;
- break;
- case IPC_INFO:
- case SEM_INFO:
- /*
- * System level information
- */
- return 0;
- default:
- return -EINVAL;
- }
- return smk_curacc_sem(sma, may);
- }
- /**
- * smack_sem_semop - Smack checks of semaphore operations
- * @sma: the object
- * @sops: unused
- * @nsops: unused
- * @alter: unused
- *
- * Treated as read and write in all cases.
- *
- * Returns 0 if access is allowed, error code otherwise
- */
- static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
- unsigned nsops, int alter)
- {
- return smk_curacc_sem(sma, MAY_READWRITE);
- }
- /**
- * smack_msg_alloc_security - Set the security blob for msg
- * @msq: the object
- *
- * Returns 0
- */
- static int smack_msg_queue_alloc_security(struct msg_queue *msq)
- {
- struct kern_ipc_perm *kisp = &msq->q_perm;
- kisp->security = smk_of_current();
- return 0;
- }
- /**
- * smack_msg_free_security - Clear the security blob for msg
- * @msq: the object
- *
- * Clears the blob pointer
- */
- static void smack_msg_queue_free_security(struct msg_queue *msq)
- {
- struct kern_ipc_perm *kisp = &msq->q_perm;
- kisp->security = NULL;
- }
- /**
- * smack_of_msq - the smack pointer for the msq
- * @msq: the object
- *
- * Returns a pointer to the smack value
- */
- static char *smack_of_msq(struct msg_queue *msq)
- {
- return (char *)msq->q_perm.security;
- }
- /**
- * smk_curacc_msq : helper to check if current has access on msq
- * @msq : the msq
- * @access : access requested
- *
- * return 0 if current has access, error otherwise
- */
- static int smk_curacc_msq(struct msg_queue *msq, int access)
- {
- char *msp = smack_of_msq(msq);
- struct smk_audit_info ad;
- #ifdef CONFIG_AUDIT
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
- ad.a.u.ipc_id = msq->q_perm.id;
- #endif
- return smk_curacc(msp, access, &ad);
- }
- /**
- * smack_msg_queue_associate - Smack access check for msg_queue
- * @msq: the object
- * @msqflg: access requested
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
- {
- int may;
- may = smack_flags_to_may(msqflg);
- return smk_curacc_msq(msq, may);
- }
- /**
- * smack_msg_queue_msgctl - Smack access check for msg_queue
- * @msq: the object
- * @cmd: what it wants to do
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
- {
- int may;
- switch (cmd) {
- case IPC_STAT:
- case MSG_STAT:
- may = MAY_READ;
- break;
- case IPC_SET:
- case IPC_RMID:
- may = MAY_READWRITE;
- break;
- case IPC_INFO:
- case MSG_INFO:
- /*
- * System level information
- */
- return 0;
- default:
- return -EINVAL;
- }
- return smk_curacc_msq(msq, may);
- }
- /**
- * smack_msg_queue_msgsnd - Smack access check for msg_queue
- * @msq: the object
- * @msg: unused
- * @msqflg: access requested
- *
- * Returns 0 if current has the requested access, error code otherwise
- */
- static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
- int msqflg)
- {
- int may;
- may = smack_flags_to_may(msqflg);
- return smk_curacc_msq(msq, may);
- }
- /**
- * smack_msg_queue_msgsnd - Smack access check for msg_queue
- * @msq: the object
- * @msg: unused
- * @target: unused
- * @type: unused
- * @mode: unused
- *
- * Returns 0 if current has read and write access, error code otherwise
- */
- static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
- struct task_struct *target, long type, int mode)
- {
- return smk_curacc_msq(msq, MAY_READWRITE);
- }
- /**
- * smack_ipc_permission - Smack access for ipc_permission()
- * @ipp: the object permissions
- * @flag: access requested
- *
- * Returns 0 if current has read and write access, error code otherwise
- */
- static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
- {
- char *isp = ipp->security;
- int may = smack_flags_to_may(flag);
- struct smk_audit_info ad;
- #ifdef CONFIG_AUDIT
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
- ad.a.u.ipc_id = ipp->id;
- #endif
- return smk_curacc(isp, may, &ad);
- }
- /**
- * smack_ipc_getsecid - Extract smack security id
- * @ipp: the object permissions
- * @secid: where result will be saved
- */
- static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
- {
- char *smack = ipp->security;
- *secid = smack_to_secid(smack);
- }
- /**
- * smack_d_instantiate - Make sure the blob is correct on an inode
- * @opt_dentry: dentry where inode will be attached
- * @inode: the object
- *
- * Set the inode's security blob if it hasn't been done already.
- */
- static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
- {
- struct super_block *sbp;
- struct superblock_smack *sbsp;
- struct inode_smack *isp;
- char *csp = smk_of_current();
- char *fetched;
- char *final;
- char trattr[TRANS_TRUE_SIZE];
- int transflag = 0;
- struct dentry *dp;
- if (inode == NULL)
- return;
- isp = inode->i_security;
- mutex_lock(&isp->smk_lock);
- /*
- * If the inode is already instantiated
- * take the quick way out
- */
- if (isp->smk_flags & SMK_INODE_INSTANT)
- goto unlockandout;
- sbp = inode->i_sb;
- sbsp = sbp->s_security;
- /*
- * We're going to use the superblock default label
- * if there's no label on the file.
- */
- final = sbsp->smk_default;
- /*
- * If this is the root inode the superblock
- * may be in the process of initialization.
- * If that is the case use the root value out
- * of the superblock.
- */
- if (opt_dentry->d_parent == opt_dentry) {
- isp->smk_inode = sbsp->smk_root;
- isp->smk_flags |= SMK_INODE_INSTANT;
- goto unlockandout;
- }
- /*
- * This is pretty hackish.
- * Casey says that we shouldn't have to do
- * file system specific code, but it does help
- * with keeping it simple.
- */
- switch (sbp->s_magic) {
- case SMACK_MAGIC:
- /*
- * Casey says that it's a little embarrassing
- * that the smack file system doesn't do
- * extended attributes.
- */
- final = smack_known_star.smk_known;
- break;
- case PIPEFS_MAGIC:
- /*
- * Casey says pipes are easy (?)
- */
- final = smack_known_star.smk_known;
- break;
- case DEVPTS_SUPER_MAGIC:
- /*
- * devpts seems content with the label of the task.
- * Programs that change smack have to treat the
- * pty with respect.
- */
- final = csp;
- break;
- case SOCKFS_MAGIC:
- /*
- * Socket access is controlled by the socket
- * structures associated with the task involved.
- */
- final = smack_known_star.smk_known;
- break;
- case PROC_SUPER_MAGIC:
- /*
- * Casey says procfs appears not to care.
- * The superblock default suffices.
- */
- break;
- case TMPFS_MAGIC:
- /*
- * Device labels should come from the filesystem,
- * but watch out, because they're volitile,
- * getting recreated on every reboot.
- */
- final = smack_known_star.smk_known;
- /*
- * No break.
- *
- * If a smack value has been set we want to use it,
- * but since tmpfs isn't giving us the opportunity
- * to set mount options simulate setting the
- * superblock default.
- */
- default:
- /*
- * This isn't an understood special case.
- * Get the value from the xattr.
- */
- /*
- * UNIX domain sockets use lower level socket data.
- */
- if (S_ISSOCK(inode->i_mode)) {
- final = smack_known_star.smk_known;
- break;
- }
- /*
- * No xattr support means, alas, no SMACK label.
- * Use the aforeapplied default.
- * It would be curious if the label of the task
- * does not match that assigned.
- */
- if (inode->i_op->getxattr == NULL)
- break;
- /*
- * Get the dentry for xattr.
- */
- dp = dget(opt_dentry);
- fetched = smk_fetch(XATTR_NAME_SMACK, inode, dp);
- if (fetched != NULL) {
- final = fetched;
- if (S_ISDIR(inode->i_mode)) {
- trattr[0] = '\0';
- inode->i_op->getxattr(dp,
- XATTR_NAME_SMACKTRANSMUTE,
- trattr, TRANS_TRUE_SIZE);
- if (strncmp(trattr, TRANS_TRUE,
- TRANS_TRUE_SIZE) == 0)
- transflag = SMK_INODE_TRANSMUTE;
- }
- }
- isp->smk_task = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
- isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
- dput(dp);
- break;
- }
- if (final == NULL)
- isp->smk_inode = csp;
- else
- isp->smk_inode = final;
- isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
- unlockandout:
- mutex_unlock(&isp->smk_lock);
- return;
- }
- /**
- * smack_getprocattr - Smack process attribute access
- * @p: the object task
- * @name: the name of the attribute in /proc/.../attr
- * @value: where to put the result
- *
- * Places a copy of the task Smack into value
- *
- * Returns the length of the smack label or an error code
- */
- static int smack_getprocattr(struct task_struct *p, char *name, char **value)
- {
- char *cp;
- int slen;
- if (strcmp(name, "current") != 0)
- return -EINVAL;
- cp = kstrdup(smk_of_task_struct(p), GFP_KERNEL);
- if (cp == NULL)
- return -ENOMEM;
- slen = strlen(cp);
- *value = cp;
- return slen;
- }
- /**
- * smack_setprocattr - Smack process attribute setting
- * @p: the object task
- * @name: the name of the attribute in /proc/.../attr
- * @value: the value to set
- * @size: the size of the value
- *
- * Sets the Smack value of the task. Only setting self
- * is permitted and only with privilege
- *
- * Returns the length of the smack label or an error code
- */
- static int smack_setprocattr(struct task_struct *p, char *name,
- void *value, size_t size)
- {
- int rc;
- struct task_smack *tsp;
- struct task_smack *oldtsp;
- struct cred *new;
- char *newsmack;
- /*
- * Changing another process' Smack value is too dangerous
- * and supports no sane use case.
- */
- if (p != current)
- return -EPERM;
- if (!capable(CAP_MAC_ADMIN))
- return -EPERM;
- if (value == NULL || size == 0 || size >= SMK_LABELLEN)
- return -EINVAL;
- if (strcmp(name, "current") != 0)
- return -EINVAL;
- newsmack = smk_import(value, size);
- if (newsmack == NULL)
- return -EINVAL;
- /*
- * No process is ever allowed the web ("@") label.
- */
- if (newsmack == smack_known_web.smk_known)
- return -EPERM;
- oldtsp = p->cred->security;
- new = prepare_creds();
- if (new == NULL)
- return -ENOMEM;
- tsp = new_task_smack(newsmack, oldtsp->smk_forked, GFP_KERNEL);
- if (tsp == NULL) {
- kfree(new);
- return -ENOMEM;
- }
- rc = smk_copy_rules(&tsp->smk_rules, &oldtsp->smk_rules, GFP_KERNEL);
- if (rc != 0)
- return rc;
- new->security = tsp;
- commit_creds(new);
- return size;
- }
- /**
- * smack_unix_stream_connect - Smack access on UDS
- * @sock: one sock
- * @other: the other sock
- * @newsk: unused
- *
- * Return 0 if a subject with the smack of sock could access
- * an object with the smack of other, otherwise an error code
- */
- static int smack_unix_stream_connect(struct sock *sock,
- struct sock *other, struct sock *newsk)
- {
- struct socket_smack *ssp = sock->sk_security;
- struct socket_smack *osp = other->sk_security;
- struct socket_smack *nsp = newsk->sk_security;
- struct smk_audit_info ad;
- int rc = 0;
- #ifdef CONFIG_AUDIT
- struct lsm_network_audit net;
- smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
- smk_ad_setfield_u_net_sk(&ad, other);
- #endif
- if (!capable(CAP_MAC_OVERRIDE))
- rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
- /*
- * Cross reference the peer labels for SO_PEERSEC.
- */
- if (rc == 0) {
- nsp->smk_packet = ssp->smk_out;
- ssp->smk_packet = osp->smk_out;
- }
- return rc;
- }
- /**
- * smack_unix_may_send - Smack access on UDS
- * @sock: one socket
- * @other: the other socket
- *
- * Return 0 if a subject with the smack of sock could access
- * an object with the smack of other, otherwise an error code
- */
- static int smack_unix_may_send(struct socket *sock, struct socket *other)
- {
- struct socket_smack *ssp = sock->sk->sk_security;
- struct socket_smack *osp = other->sk->sk_security;
- struct smk_audit_info ad;
- int rc = 0;
- #ifdef CONFIG_AUDIT
- struct lsm_network_audit net;
- smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
- smk_ad_setfield_u_net_sk(&ad, other->sk);
- #endif
- if (!capable(CAP_MAC_OVERRIDE))
- rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
- return rc;
- }
- /**
- * smack_socket_sendmsg - Smack check based on destination host
- * @sock: the socket
- * @msg: the message
- * @size: the size of the message
- *
- * Return 0 if the current subject can write to the destination
- * host. This is only a question if the destination is a single
- * label host.
- */
- static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
- int size)
- {
- struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
- /*
- * Perfectly reasonable for this to be NULL
- */
- if (sip == NULL || sip->sin_family != AF_INET)
- return 0;
- return smack_netlabel_send(sock->sk, sip);
- }
- /**
- * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
- * @sap: netlabel secattr
- * @ssp: socket security information
- *
- * Returns a pointer to a Smack label found on the label list.
- */
- static char *smack_from_secattr(struct netlbl_lsm_secattr *sap,
- struct socket_smack *ssp)
- {
- struct smack_known *skp;
- char smack[SMK_LABELLEN];
- char *sp;
- int pcat;
- if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
- /*
- * Looks like a CIPSO packet.
- * If there are flags but no level netlabel isn't
- * behaving the way we expect it to.
- *
- * Get the categories, if any
- * Without guidance regarding the smack value
- * for the packet fall back on the network
- * ambient value.
- */
- memset(smack, '\0', SMK_LABELLEN);
- if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
- for (pcat = -1;;) {
- pcat = netlbl_secattr_catmap_walk(
- sap->attr.mls.cat, pcat + 1);
- if (pcat < 0)
- break;
- smack_catset_bit(pcat, smack);
- }
- /*
- * If it is CIPSO using smack direct mapping
- * we are already done. WeeHee.
- */
- if (sap->attr.mls.lvl == smack_cipso_direct) {
- /*
- * The label sent is usually on the label list.
- *
- * If it is not we may still want to allow the
- * delivery.
- *
- * If the recipient is accepting all packets
- * because it is using the star ("*") label
- * for SMACK64IPIN provide the web ("@") label
- * so that a directed response will succeed.
- * This is not very correct from a MAC point
- * of view, but gets around the problem that
- * locking prevents adding the newly discovered
- * label to the list.
- * The case where the recipient is not using
- * the star label should obviously fail.
- * The easy way to do this is to provide the
- * star label as the subject label.
- */
- skp = smk_find_entry(smack);
- if (skp != NULL)
- return skp->smk_known;
- if (ssp != NULL &&
- ssp->smk_in == smack_known_star.smk_known)
- return smack_known_web.smk_known;
- return smack_known_star.smk_known;
- }
- /*
- * Look it up in the supplied table if it is not
- * a direct mapping.
- */
- sp = smack_from_cipso(sap->attr.mls.lvl, smack);
- if (sp != NULL)
- return sp;
- if (ssp != NULL && ssp->smk_in == smack_known_star.smk_known)
- return smack_known_web.smk_known;
- return smack_known_star.smk_known;
- }
- if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
- /*
- * Looks like a fallback, which gives us a secid.
- */
- sp = smack_from_secid(sap->attr.secid);
- /*
- * This has got to be a bug because it is
- * impossible to specify a fallback without
- * specifying the label, which will ensure
- * it has a secid, and the only way to get a
- * secid is from a fallback.
- */
- BUG_ON(sp == NULL);
- return sp;
- }
- /*
- * Without guidance regarding the smack value
- * for the packet fall back on the network
- * ambient value.
- */
- return smack_net_ambient;
- }
- /**
- * smack_socket_sock_rcv_skb - Smack packet delivery access check
- * @sk: socket
- * @skb: packet
- *
- * Returns 0 if the packet should be delivered, an error code otherwise
- */
- static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
- {
- struct netlbl_lsm_secattr secattr;
- struct socket_smack *ssp = sk->sk_security;
- char *csp;
- int rc;
- struct smk_audit_info ad;
- #ifdef CONFIG_AUDIT
- struct lsm_network_audit net;
- #endif
- if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
- return 0;
- /*
- * Translate what netlabel gave us.
- */
- netlbl_secattr_init(&secattr);
- rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
- if (rc == 0)
- csp = smack_from_secattr(&secattr, ssp);
- else
- csp = smack_net_ambient;
- netlbl_secattr_destroy(&secattr);
- #ifdef CONFIG_AUDIT
- smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
- ad.a.u.net->family = sk->sk_family;
- ad.a.u.net->netif = skb->skb_iif;
- ipv4_skb_to_auditdata(skb, &ad.a, NULL);
- #endif
- /*
- * Receiving a packet requires that the other end
- * be able to write here. Read access is not required.
- * This is the simplist possible security model
- * for networking.
- */
- rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad);
- if (rc != 0)
- netlbl_skbuff_err(skb, rc, 0);
- return rc;
- }
- /**
- * smack_socket_getpeersec_stream - pull in packet label
- * @sock: the socket
- * @optval: user's destination
- * @optlen: size thereof
- * @len: max thereof
- *
- * returns zero on success, an error code otherwise
- */
- static int smack_socket_getpeersec_stream(struct socket *sock,
- char __user *optval,
- int __user *optlen, unsigned len)
- {
- struct socket_smack *ssp;
- char *rcp = "";
- int slen = 1;
- int rc = 0;
- ssp = sock->sk->sk_security;
- if (ssp->smk_packet != NULL) {
- rcp = ssp->smk_packet;
- slen = strlen(rcp) + 1;
- }
- if (slen > len)
- rc = -ERANGE;
- else if (copy_to_user(optval, rcp, slen) != 0)
- rc = -EFAULT;
- if (put_user(slen, optlen) != 0)
- rc = -EFAULT;
- return rc;
- }
- /**
- * smack_socket_getpeersec_dgram - pull in packet label
- * @sock: the peer socket
- * @skb: packet data
- * @secid: pointer to where to put the secid of the packet
- *
- * Sets the netlabel socket state on sk from parent
- */
- static int smack_socket_getpeersec_dgram(struct socket *sock,
- struct sk_buff *skb, u32 *secid)
- {
- struct netlbl_lsm_secattr secattr;
- struct socket_smack *ssp = NULL;
- char *sp;
- int family = PF_UNSPEC;
- u32 s = 0; /* 0 is the invalid secid */
- int rc;
- if (skb != NULL) {
- if (skb->protocol == htons(ETH_P_IP))
- family = PF_INET;
- else if (skb->protocol == htons(ETH_P_IPV6))
- family = PF_INET6;
- }
- if (family == PF_UNSPEC && sock != NULL)
- family = sock->sk->sk_family;
- if (family == PF_UNIX) {
- ssp = sock->sk->sk_security;
- s = smack_to_secid(ssp->smk_out);
- } else if (family == PF_INET || family == PF_INET6) {
- /*
- * Translate what netlabel gave us.
- */
- if (sock != NULL && sock->sk != NULL)
- ssp = sock->sk->sk_security;
- netlbl_secattr_init(&secattr);
- rc = netlbl_skbuff_getattr(skb, family, &secattr);
- if (rc == 0) {
- sp = smack_from_secattr(&secattr, ssp);
- s = smack_to_secid(sp);
- }
- netlbl_secattr_destroy(&secattr);
- }
- *secid = s;
- if (s == 0)
- return -EINVAL;
- return 0;
- }
- /**
- * smack_sock_graft - Initialize a newly created socket with an existing sock
- * @sk: child sock
- * @parent: parent socket
- *
- * Set the smk_{in,out} state of an existing sock based on the process that
- * is creating the new socket.
- */
- static void smack_sock_graft(struct sock *sk, struct socket *parent)
- {
- struct socket_smack *ssp;
- if (sk == NULL ||
- (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
- return;
- ssp = sk->sk_security;
- ssp->smk_in = ssp->smk_out = smk_of_current();
- /* cssp->smk_packet is already set in smack_inet_csk_clone() */
- }
- /**
- * smack_inet_conn_request - Smack access check on connect
- * @sk: socket involved
- * @skb: packet
- * @req: unused
- *
- * Returns 0 if a task with the packet label could write to
- * the socket, otherwise an error code
- */
- static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
- struct request_sock *req)
- {
- u16 family = sk->sk_family;
- struct socket_smack *ssp = sk->sk_security;
- struct netlbl_lsm_secattr secattr;
- struct sockaddr_in addr;
- struct iphdr *hdr;
- char *sp;
- int rc;
- struct smk_audit_info ad;
- #ifdef CONFIG_AUDIT
- struct lsm_network_audit net;
- #endif
- /* handle mapped IPv4 packets arriving via IPv6 sockets */
- if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
- family = PF_INET;
- netlbl_secattr_init(&secattr);
- rc = netlbl_skbuff_getattr(skb, family, &secattr);
- if (rc == 0)
- sp = smack_from_secattr(&secattr, ssp);
- else
- sp = smack_known_huh.smk_known;
- netlbl_secattr_destroy(&secattr);
- #ifdef CONFIG_AUDIT
- smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
- ad.a.u.net->family = family;
- ad.a.u.net->netif = skb->skb_iif;
- ipv4_skb_to_auditdata(skb, &ad.a, NULL);
- #endif
- /*
- * Receiving a packet requires that the other end be able to write
- * here. Read access is not required.
- */
- rc = smk_access(sp, ssp->smk_in, MAY_WRITE, &ad);
- if (rc != 0)
- return rc;
- /*
- * Save the peer's label in the request_sock so we can later setup
- * smk_packet in the child socket so that SO_PEERCRED can report it.
- */
- req->peer_secid = smack_to_secid(sp);
- /*
- * We need to decide if we want to label the incoming connection here
- * if we do we only need to label the request_sock and the stack will
- * propagate the wire-label to the sock when it is created.
- */
- hdr = ip_hdr(skb);
- addr.sin_addr.s_addr = hdr->saddr;
- rcu_read_lock();
- if (smack_host_label(&addr) == NULL) {
- rcu_read_unlock();
- netlbl_secattr_init(&secattr);
- smack_to_secattr(sp, &secattr);
- rc = netlbl_req_setattr(req, &secattr);
- netlbl_secattr_destroy(&secattr);
- } else {
- rcu_read_unlock();
- netlbl_req_delattr(req);
- }
- return rc;
- }
- /**
- * smack_inet_csk_clone - Copy the connection information to the new socket
- * @sk: the new socket
- * @req: the connection's request_sock
- *
- * Transfer the connection's peer label to the newly created socket.
- */
- static void smack_inet_csk_clone(struct sock *sk,
- const struct request_sock *req)
- {
- struct socket_smack *ssp = sk->sk_security;
- if (req->peer_secid != 0)
- ssp->smk_packet = smack_from_secid(req->peer_secid);
- else
- ssp->smk_packet = NULL;
- }
- /*
- * Key management security hooks
- *
- * Casey has not tested key support very heavily.
- * The permission check is most likely too restrictive.
- * If you care about keys please have a look.
- */
- #ifdef CONFIG_KEYS
- /**
- * smack_key_alloc - Set the key security blob
- * @key: object
- * @cred: the credentials to use
- * @flags: unused
- *
- * No allocation required
- *
- * Returns 0
- */
- static int smack_key_alloc(struct key *key, const struct cred *cred,
- unsigned long flags)
- {
- key->security = smk_of_task(cred->security);
- return 0;
- }
- /**
- * smack_key_free - Clear the key security blob
- * @key: the object
- *
- * Clear the blob pointer
- */
- static void smack_key_free(struct key *key)
- {
- key->security = NULL;
- }
- /*
- * smack_key_permission - Smack access on a key
- * @key_ref: gets to the object
- * @cred: the credentials to use
- * @perm: unused
- *
- * Return 0 if the task has read and write to the object,
- * an error code otherwise
- */
- static int smack_key_permission(key_ref_t key_ref,
- const struct cred *cred, key_perm_t perm)
- {
- struct key *keyp;
- struct smk_audit_info ad;
- char *tsp = smk_of_task(cred->security);
- keyp = key_ref_to_ptr(key_ref);
- if (keyp == NULL)
- return -EINVAL;
- /*
- * If the key hasn't been initialized give it access so that
- * it may do so.
- */
- if (keyp->security == NULL)
- return 0;
- /*
- * This should not occur
- */
- if (tsp == NULL)
- return -EACCES;
- #ifdef CONFIG_AUDIT
- smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
- ad.a.u.key_struct.key = keyp->serial;
- ad.a.u.key_struct.key_desc = keyp->description;
- #endif
- return smk_access(tsp, keyp->security,
- MAY_READWRITE, &ad);
- }
- #endif /* CONFIG_KEYS */
- /*
- * Smack Audit hooks
- *
- * Audit requires a unique representation of each Smack specific
- * rule. This unique representation is used to distinguish the
- * object to be audited from remaining kernel objects and also
- * works as a glue between the audit hooks.
- *
- * Since repository entries are added but never deleted, we'll use
- * the smack_known label address related to the given audit rule as
- * the needed unique representation. This also better fits the smack
- * model where nearly everything is a label.
- */
- #ifdef CONFIG_AUDIT
- /**
- * smack_audit_rule_init - Initialize a smack audit rule
- * @field: audit rule fields given from user-space (audit.h)
- * @op: required testing operator (=, !=, >, <, ...)
- * @rulestr: smack label to be audited
- * @vrule: pointer to save our own audit rule representation
- *
- * Prepare to audit cases where (@field @op @rulestr) is true.
- * The label to be audited is created if necessay.
- */
- static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
- {
- char **rule = (char **)vrule;
- *rule = NULL;
- if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
- return -EINVAL;
- if (op != Audit_equal && op != Audit_not_equal)
- return -EINVAL;
- *rule = smk_import(rulestr, 0);
- return 0;
- }
- /**
- * smack_audit_rule_known - Distinguish Smack audit rules
- * @krule: rule of interest, in Audit kernel representation format
- *
- * This is used to filter Smack rules from remaining Audit ones.
- * If it's proved that this rule belongs to us, the
- * audit_rule_match hook will be called to do the final judgement.
- */
- static int smack_audit_rule_known(struct audit_krule *krule)
- {
- struct audit_field *f;
- int i;
- for (i = 0; i < krule->field_count; i++) {
- f = &krule->fields[i];
- if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
- return 1;
- }
- return 0;
- }
- /**
- * smack_audit_rule_match - Audit given object ?
- * @secid: security id for identifying the object to test
- * @field: audit rule flags given from user-space
- * @op: required testing operator
- * @vrule: smack internal rule presentation
- * @actx: audit context associated with the check
- *
- * The core Audit hook. It's used to take the decision of
- * whether to audit or not to audit a given object.
- */
- static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
- struct audit_context *actx)
- {
- char *smack;
- char *rule = vrule;
- if (!rule) {
- audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
- "Smack: missing rule\n");
- return -ENOENT;
- }
- if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
- return 0;
- smack = smack_from_secid(secid);
- /*
- * No need to do string comparisons. If a match occurs,
- * both pointers will point to the same smack_known
- * label.
- */
- if (op == Audit_equal)
- return (rule == smack);
- if (op == Audit_not_equal)
- return (rule != smack);
- return 0;
- }
- /**
- * smack_audit_rule_free - free smack rule representation
- * @vrule: rule to be freed.
- *
- * No memory was allocated.
- */
- static void smack_audit_rule_free(void *vrule)
- {
- /* No-op */
- }
- #endif /* CONFIG_AUDIT */
- /**
- * smack_secid_to_secctx - return the smack label for a secid
- * @secid: incoming integer
- * @secdata: destination
- * @seclen: how long it is
- *
- * Exists for networking code.
- */
- static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
- {
- char *sp = smack_from_secid(secid);
- if (secdata)
- *secdata = sp;
- *seclen = strlen(sp);
- return 0;
- }
- /**
- * smack_secctx_to_secid - return the secid for a smack label
- * @secdata: smack label
- * @seclen: how long result is
- * @secid: outgoing integer
- *
- * Exists for audit and networking code.
- */
- static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
- {
- *secid = smack_to_secid(secdata);
- return 0;
- }
- /**
- * smack_release_secctx - don't do anything.
- * @secdata: unused
- * @seclen: unused
- *
- * Exists to make sure nothing gets done, and properly
- */
- static void smack_release_secctx(char *secdata, u32 seclen)
- {
- }
- static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
- {
- return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
- }
- static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
- {
- return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
- }
- static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
- {
- int len = 0;
- len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true);
- if (len < 0)
- return len;
- *ctxlen = len;
- return 0;
- }
- struct security_operations smack_ops = {
- .name = "smack",
- .ptrace_access_check = smack_ptrace_access_check,
- .ptrace_traceme = smack_ptrace_traceme,
- .syslog = smack_syslog,
- .sb_alloc_security = smack_sb_alloc_security,
- .sb_free_security = smack_sb_free_security,
- .sb_copy_data = smack_sb_copy_data,
- .sb_kern_mount = smack_sb_kern_mount,
- .sb_statfs = smack_sb_statfs,
- .sb_mount = smack_sb_mount,
- .sb_umount = smack_sb_umount,
- .bprm_set_creds = smack_bprm_set_creds,
- .bprm_committing_creds = smack_bprm_committing_creds,
- .bprm_secureexec = smack_bprm_secureexec,
- .inode_alloc_security = smack_inode_alloc_security,
- .inode_free_security = smack_inode_free_security,
- .inode_init_security = smack_inode_init_security,
- .inode_link = smack_inode_link,
- .inode_unlink = smack_inode_unlink,
- .inode_rmdir = smack_inode_rmdir,
- .inode_rename = smack_inode_rename,
- .inode_permission = smack_inode_permission,
- .inode_setattr = smack_inode_setattr,
- .inode_getattr = smack_inode_getattr,
- .inode_setxattr = smack_inode_setxattr,
- .inode_post_setxattr = smack_inode_post_setxattr,
- .inode_getxattr = smack_inode_getxattr,
- .inode_removexattr = smack_inode_removexattr,
- .inode_getsecurity = smack_inode_getsecurity,
- .inode_setsecurity = smack_inode_setsecurity,
- .inode_listsecurity = smack_inode_listsecurity,
- .inode_getsecid = smack_inode_getsecid,
- .file_permission = smack_file_permission,
- .file_alloc_security = smack_file_alloc_security,
- .file_free_security = smack_file_free_security,
- .file_ioctl = smack_file_ioctl,
- .file_lock = smack_file_lock,
- .file_fcntl = smack_file_fcntl,
- .file_mmap = smack_file_mmap,
- .file_set_fowner = smack_file_set_fowner,
- .file_send_sigiotask = smack_file_send_sigiotask,
- .file_receive = smack_file_receive,
- .dentry_open = smack_dentry_open,
- .cred_alloc_blank = smack_cred_alloc_blank,
- .cred_free = smack_cred_free,
- .cred_prepare = smack_cred_prepare,
- .cred_transfer = smack_cred_transfer,
- .kernel_act_as = smack_kernel_act_as,
- .kernel_create_files_as = smack_kernel_create_files_as,
- .task_setpgid = smack_task_setpgid,
- .task_getpgid = smack_task_getpgid,
- .task_getsid = smack_task_getsid,
- .task_getsecid = smack_task_getsecid,
- .task_setnice = smack_task_setnice,
- .task_setioprio = smack_task_setioprio,
- .task_getioprio = smack_task_getioprio,
- .task_setscheduler = smack_task_setscheduler,
- .task_getscheduler = smack_task_getscheduler,
- .task_movememory = smack_task_movememory,
- .task_kill = smack_task_kill,
- .task_wait = smack_task_wait,
- .task_to_inode = smack_task_to_inode,
- .ipc_permission = smack_ipc_permission,
- .ipc_getsecid = smack_ipc_getsecid,
- .msg_msg_alloc_security = smack_msg_msg_alloc_security,
- .msg_msg_free_security = smack_msg_msg_free_security,
- .msg_queue_alloc_security = smack_msg_queue_alloc_security,
- .msg_queue_free_security = smack_msg_queue_free_security,
- .msg_queue_associate = smack_msg_queue_associate,
- .msg_queue_msgctl = smack_msg_queue_msgctl,
- .msg_queue_msgsnd = smack_msg_queue_msgsnd,
- .msg_queue_msgrcv = smack_msg_queue_msgrcv,
- .shm_alloc_security = smack_shm_alloc_security,
- .shm_free_security = smack_shm_free_security,
- .shm_associate = smack_shm_associate,
- .shm_shmctl = smack_shm_shmctl,
- .shm_shmat = smack_shm_shmat,
- .sem_alloc_security = smack_sem_alloc_security,
- .sem_free_security = smack_sem_free_security,
- .sem_associate = smack_sem_associate,
- .sem_semctl = smack_sem_semctl,
- .sem_semop = smack_sem_semop,
- .d_instantiate = smack_d_instantiate,
- .getprocattr = smack_getprocattr,
- .setprocattr = smack_setprocattr,
- .unix_stream_connect = smack_unix_stream_connect,
- .unix_may_send = smack_unix_may_send,
- .socket_post_create = smack_socket_post_create,
- .socket_connect = smack_socket_connect,
- .socket_sendmsg = smack_socket_sendmsg,
- .socket_sock_rcv_skb = smack_socket_sock_rcv_skb,
- .socket_getpeersec_stream = smack_socket_getpeersec_stream,
- .socket_getpeersec_dgram = smack_socket_getpeersec_dgram,
- .sk_alloc_security = smack_sk_alloc_security,
- .sk_free_security = smack_sk_free_security,
- .sock_graft = smack_sock_graft,
- .inet_conn_request = smack_inet_conn_request,
- .inet_csk_clone = smack_inet_csk_clone,
- /* key management security hooks */
- #ifdef CONFIG_KEYS
- .key_alloc = smack_key_alloc,
- .key_free = smack_key_free,
- .key_permission = smack_key_permission,
- #endif /* CONFIG_KEYS */
- /* Audit hooks */
- #ifdef CONFIG_AUDIT
- .audit_rule_init = smack_audit_rule_init,
- .audit_rule_known = smack_audit_rule_known,
- .audit_rule_match = smack_audit_rule_match,
- .audit_rule_free = smack_audit_rule_free,
- #endif /* CONFIG_AUDIT */
- .secid_to_secctx = smack_secid_to_secctx,
- .secctx_to_secid = smack_secctx_to_secid,
- .release_secctx = smack_release_secctx,
- .inode_notifysecctx = smack_inode_notifysecctx,
- .inode_setsecctx = smack_inode_setsecctx,
- .inode_getsecctx = smack_inode_getsecctx,
- };
- static __init void init_smack_known_list(void)
- {
- /*
- * Initialize CIPSO locks
- */
- spin_lock_init(&smack_known_huh.smk_cipsolock);
- spin_lock_init(&smack_known_hat.smk_cipsolock);
- spin_lock_init(&smack_known_star.smk_cipsolock);
- spin_lock_init(&smack_known_floor.smk_cipsolock);
- spin_lock_init(&smack_known_invalid.smk_cipsolock);
- spin_lock_init(&smack_known_web.smk_cipsolock);
- /*
- * Initialize rule list locks
- */
- mutex_init(&smack_known_huh.smk_rules_lock);
- mutex_init(&smack_known_hat.smk_rules_lock);
- mutex_init(&smack_known_floor.smk_rules_lock);
- mutex_init(&smack_known_star.smk_rules_lock);
- mutex_init(&smack_known_invalid.smk_rules_lock);
- mutex_init(&smack_known_web.smk_rules_lock);
- /*
- * Initialize rule lists
- */
- INIT_LIST_HEAD(&smack_known_huh.smk_rules);
- INIT_LIST_HEAD(&smack_known_hat.smk_rules);
- INIT_LIST_HEAD(&smack_known_star.smk_rules);
- INIT_LIST_HEAD(&smack_known_floor.smk_rules);
- INIT_LIST_HEAD(&smack_known_invalid.smk_rules);
- INIT_LIST_HEAD(&smack_known_web.smk_rules);
- /*
- * Create the known labels list
- */
- list_add(&smack_known_huh.list, &smack_known_list);
- list_add(&smack_known_hat.list, &smack_known_list);
- list_add(&smack_known_star.list, &smack_known_list);
- list_add(&smack_known_floor.list, &smack_known_list);
- list_add(&smack_known_invalid.list, &smack_known_list);
- list_add(&smack_known_web.list, &smack_known_list);
- }
- /**
- * smack_init - initialize the smack system
- *
- * Returns 0
- */
- static __init int smack_init(void)
- {
- struct cred *cred;
- struct task_smack *tsp;
- if (!security_module_enable(&smack_ops))
- return 0;
- tsp = new_task_smack(smack_known_floor.smk_known,
- smack_known_floor.smk_known, GFP_KERNEL);
- if (tsp == NULL)
- return -ENOMEM;
- printk(KERN_INFO "Smack: Initializing.\n");
- /*
- * Set the security state for the initial task.
- */
- cred = (struct cred *) current->cred;
- cred->security = tsp;
- /* initialize the smack_known_list */
- init_smack_known_list();
- /*
- * Register with LSM
- */
- if (register_security(&smack_ops))
- panic("smack: Unable to register with kernel.\n");
- return 0;
- }
- /*
- * Smack requires early initialization in order to label
- * all processes and objects when they are created.
- */
- security_initcall(smack_init);
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