#!/usr/bin/env bash
#
# GNU/Linux does not really require something like RelativeLink.c
# However, we do want to have the same look and feel with similar features.
#
# Copyright 2017 The Tor Project.  See LICENSE for licensing information.

complain_dialog_title="Tor Browser"

# First, make sure DISPLAY is set.  If it isn't, we're hosed; scream
# at stderr and die.
if [ "x$DISPLAY" = "x" ]; then
    echo "$complain_dialog_title must be run within the X Window System." >&2
    echo "Exiting." >&2
    exit 1
fi

# Second, make sure this script wasn't started as 'sh start-tor-browser' or
# similar.
if [ "x$BASH" = "x" ]; then
    echo "$complain_dialog_title should be started as './start-tor-browser'"
    echo "Exiting." >&2
    exit 1;
fi

# Do not (try to) connect to the session manager
unset SESSION_MANAGER

# Complain about an error, by any means necessary.
# Usage: complain message
# message must not begin with a dash.
complain () {
	# Trim leading newlines, to avoid breaking formatting in some dialogs.
	complain_message="`echo "$1" | sed '/./,$!d'`"

	# If we're being run in debug/verbose mode, complain to stderr.
	if [ "$show_output" -eq 1 ]; then
		echo "$complain_message" >&2
		return
	fi

	# Otherwise, we're being run by a GUI program of some sort;
	# try to pop up a message in the GUI in the nicest way
	# possible.
	#
	# In mksh, non-existent commands return 127; I'll assume all
	# other shells set the same exit code if they can't run a
	# command.  (xmessage returns 1 if the user clicks the WM
	# close button, so we do need to look at the exact exit code,
	# not just assume the command failed to display a message if
	# it returns non-zero.)

	# First, try zenity.
	zenity --error \
		--title="$complain_dialog_title" \
		--text="$complain_message"
	if [ "$?" -ne 127 ]; then
		return
	fi

	# Try kdialog.
	kdialog --title "$complain_dialog_title" \
		--error "$complain_message"
	if [ "$?" -ne 127 ]; then
		return
	fi

	# Try xmessage.
	xmessage -title "$complain_dialog_title" \
		-center \
		-buttons OK \
		-default OK \
		-xrm '*message.scrollVertical: Never' \
		"$complain_message"
	if [ "$?" -ne 127 ]; then
		return
	fi

	# Try gxmessage.  This one isn't installed by default on
	# Debian with the default GNOME installation, so it seems to
	# be the least likely program to have available, but it might
	# be used by one of the 'lightweight' Gtk-based desktop
	# environments.
	gxmessage -title "$complain_dialog_title" \
		-center \
		-buttons GTK_STOCK_OK \
		-default OK \
		"$complain_message"
	if [ "$?" -ne 127 ]; then
		return
	fi
}

if [ "`id -u`" -eq 0 ]; then
	complain "The Tor Browser Bundle should not be run as root.  Exiting."
	exit 1
fi

if ! grep -q 'ARM' /proc/cpuinfo; then
        # Assume we're on an x86 machine, so check for SSE2.
        if test -r /proc/cpuinfo && ! grep -q '^flags\s*:.* sse2' /proc/cpuinfo; then
                complain "Tor Browser requires a CPU with SSE2 support.  Exiting."
                exit 1
        fi
fi

tbb_usage () {
    printf "\nTor Browser Script Options\n"
    printf "  --verbose         Display Tor and Firefox output in the terminal\n"
    printf "  --log [file]      Record Tor and Firefox output in file (default: tor-browser.log)\n"
    printf "  --detach          Detach from terminal and run Tor Browser in the background.\n"
    printf "  --register-app    Register Tor Browser as a desktop app for this user\n"
    printf "  --unregister-app  Unregister Tor Browser as a desktop app for this user\n"
}
log_output=0
show_output=0
detach=0
show_usage=0
register_desktop_app=0
logfile=/dev/null
while :
do
    case "$1" in
      --detach)
          detach=1
          shift
          ;;
      -v | --verbose | -d | --debug)
          show_output=1
          verbose_arg="$2"
          shift
          ;;
      -h | "-?" | --help | -help)
          show_usage=1
          show_output=1
          shift
          ;;
      -l | --log)
          if [ -z "$2" -o "${2:0:1}" == "-" ]; then
             printf "Logging Tor Browser debug information to tor-browser.log\n"
             logfile="../tor-browser.log"
          elif [ "${2:0:1}" == "/" -o "${2:0:1}" == "~" ]; then
             printf "Logging Tor Browser debug information to %s\n" "$2"
             logfile="$2"
             shift
          else
             printf "Logging Tor Browser debug information to %s\n" "$2"
             logfile="../$2"
             shift
          fi
          log_output=1
          shift
          ;;
      --register-app)
          register_desktop_app=1
          show_output=1
          shift
          ;;
      --unregister-app)
          register_desktop_app=-1
          show_output=1
          shift
          ;;
      *) # No more options
          break
          ;;
    esac
done

# We can't detach and show output at the same time..
if [ "$show_output" -eq 1 -a "$detach" -eq 1 ]; then
    detach=0
fi

if [ "$show_output" -eq 0 ]; then
    # If the user hasn't requested 'debug mode' or --help, close stdout and stderr,
    # to keep Firefox and the stuff loaded by/for it (including the
    # system's shared-library loader) from printing messages to
    # $HOME/.xsession-errors or other files. (Users wouldn't have seen
    # messages there anyway.)
    exec > "$logfile"
    exec 2> "$logfile"
fi

# If XAUTHORITY is unset, set it to its default value of $HOME/.Xauthority
# before we change HOME below.  (See xauth(1) and #1945.)  XDM and KDM rely
# on applications using this default value.
if [ -z "$XAUTHORITY" ]; then
	XAUTHORITY=~/.Xauthority
	export XAUTHORITY
fi

# If this script is being run through a symlink, we need to know where
# in the filesystem the script itself is, not where the symlink is.
myname="$0"
if [ -L "$myname" ]; then
	# XXX readlink is not POSIX, but is present in GNU coreutils
	# and on FreeBSD.  Unfortunately, the -f option (which follows
	# a whole chain of symlinks until it reaches a non-symlink
	# path name) is a GNUism, so we have to have a fallback for
	# FreeBSD.  Fortunately, FreeBSD has realpath instead;
	# unfortunately, that's also non-POSIX and is not present in
	# GNU coreutils.
	#
	# If this launcher were a C program, we could just use the
	# realpath function, which *is* POSIX.  Too bad POSIX didn't
	# make that function accessible to shell scripts.

	# If realpath is available, use it; it Does The Right Thing.
	possibly_my_real_name="`realpath "$myname" 2>/dev/null`"
	if [ "$?" -eq 0 ]; then
		myname="$possibly_my_real_name"
	else
		# realpath is not available; hopefully readlink -f works.
		myname="`readlink -f "$myname" 2>/dev/null`"
		if [ "$?" -ne 0 ]; then
			# Ugh.
			complain "start-tor-browser cannot be run using a symlink on this operating system."
		fi
	fi
fi

# Try to be agnostic to where we're being started from, chdir to where
# the script is.
mydir="`dirname "$myname"`"
test -d "$mydir" && cd "$mydir"

# If ${PWD} results in a zero length string, we can try something else...
if [ ! "${PWD}" ]; then
	# "hacking around some braindamage"
	PWD="`pwd`"
	surveysays="This system has a messed up shell.\n"
fi

# This is a fix for an ibus issue on some Linux systems. See #9353 for more
# details. The symlink needs to be created before we change HOME.
if [ ! -d ".config/ibus" ]; then
  mkdir -p .config/ibus
  ln -nsf ~/.config/ibus/bus .config/ibus
fi

# Fix up .desktop Icon and Exec Paths, and update the .desktop file from the
# canonical version if it was changed by the updater.
cp start-tor-browser.desktop ../
sed -i -e "s,^Name=.*,Name=Tor Browser,g" ../start-tor-browser.desktop
sed -i -e "s,^Icon=.*,Icon=$PWD/browser/chrome/icons/default/default128.png,g" ../start-tor-browser.desktop
sed -i -e "s,^Exec=.*,Exec=sh -c '\"$PWD/start-tor-browser\" --detach || ([ !  -x \"$PWD/start-tor-browser\" ] \&\& \"\$(dirname \"\$*\")\"/Browser/start-tor-browser --detach)' dummy %k,g" ../start-tor-browser.desktop

if [ "$register_desktop_app" -eq 1 ]; then
	mkdir -p "$HOME/.local/share/applications/"
	cp ../start-tor-browser.desktop "$HOME/.local/share/applications/"
	update-desktop-database "$HOME/.local/share/applications/"
	printf "Tor Browser has been registered as a desktop app for this user in ~/.local/share/applications/\n"
	exit 0
fi

if [ "$register_desktop_app" -eq -1 ]; then
	if [ -e "$HOME/.local/share/applications/start-tor-browser.desktop" ]; then
		rm -f "$HOME/.local/share/applications/start-tor-browser.desktop"
		update-desktop-database "$HOME/.local/share/applications/"
		printf "Tor Browser has been removed as a user desktop app (from ~/.local/share/applications/)\n"
	else
		printf "Tor Browser does not appear to be a desktop app (not present in ~/.local/share/applications/)\n"
	fi
	exit 0
fi

HOME="${PWD}"
export HOME

SYSARCHITECTURE=$(getconf LONG_BIT)
TORARCHITECTURE=$(expr "$(file TorBrowser/Tor/tor)" : '.*ELF \([[:digit:]]*\)')

if [ $SYSARCHITECTURE -ne $TORARCHITECTURE ]; then
   complain "Wrong architecture? 32-bit vs. 64-bit."
   exit 1
fi

[% IF c("var/asan") -%]
# We need to disable LSan which is enabled by default now. Otherwise we'll get
# a crash during shutdown: https://bugs.torproject.org/10599#comment:59
ASAN_OPTIONS="detect_leaks=0"
export ASAN_OPTIONS
[% END -%]

function setControlPortPasswd() {
    local ctrlPasswd=$1

    if test -z "$ctrlPasswd" -o "$ctrlPasswd" = $'\"secret\"' ; then
        unset TOR_CONTROL_PASSWD
        return
    fi

    if test "${ctrlPasswd:0:1}" = $'\"'; then  # First 2 chars were '"
        printf "Using system Tor process.\n"
        export TOR_CONTROL_PASSWD
    else
        complain "There seems to have been a quoting problem with your \
TOR_CONTROL_PASSWD environment variable."
	echo "The Tor ControlPort password should be given inside double"
	echo "quotes, inside single quotes. That is, if the ControlPort"
	echo 'password is “secret” (without curly quotes) then we must'
	echo "start this script after setting the environment variable"
	echo "exactly like this:"
	echo
	echo "  \$ TOR_CONTROL_PASSWD='\"secret\"' $myname"
    fi
}

# Using a system-installed Tor process with Tor Browser:
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# The Tor ControlPort password should be given inside double quotes, inside
# single quotes, i.e. if the ControlPort password is “secret” (without
# curly quotes) then we must set the environment variable *exactly* like
# this:
#
# TOR_CONTROL_PASSWD='"secret"'
#
# Yes, the variable MUST be double-quoted, then single-quoted, exactly as
# shown. This is used by TorButton and Tor Launcher to authenticate to Tor's
# ControlPort, and is necessary for using TB with a system-installed Tor.
#
# Additionally, if using a system-installed Tor, the following about:config
# options should be set (values in <> mean they are the value taken from your
# torrc):
#
# SETTING NAME                            VALUE
# network.security.ports.banned           [...],<SocksPort>,<ControlPort>
# network.proxy.socks                     127.0.0.1
# network.proxy.socks_port                <SocksPort>
# extensions.torbutton.inserted_button    true
# extensions.torbutton.launch_warning     false
# extensions.torbutton.loglevel           2
# extensions.torbutton.logmethod          0
# extensions.torlauncher.control_port      <ControlPort>
# extensions.torlauncher.loglevel          2
# extensions.torlauncher.logmethod         0
# extensions.torlauncher.prompt_at_startup false
# extensions.torlauncher.start_tor         false
#
# where the '[...]' in the banned_ports option means "leave anything that was
# already in the preference alone, just append the things specified after it".

# Either set `TOR_CONTROL_PASSWD` before running ./start-tor-browser, or put
# your password in the following line where the word “secret” is:
setControlPortPasswd ${TOR_CONTROL_PASSWD:='"secret"'}

# Set up custom bundled fonts. See fonts-conf(5).
export FONTCONFIG_PATH="${HOME}/TorBrowser/Data/fontconfig"
export FONTCONFIG_FILE="fonts.conf"

# Avoid overwriting user's dconf values. Fixes #27903.
export GSETTINGS_BACKEND=memory

# ARM requires the directory containing libssp.so.0 to be in LD_LIBRARY_PATH
if grep -q 'ARM' /proc/cpuinfo; then
        export LD_LIBRARY_PATH="${LD_LIBRARY_PATH}:${HOME}"
fi

cd "${HOME}"

# We pass all additional command-line arguments we get to Firefox.
#
# The --class parameter was added to fix bug 11102.

if [ "$show_usage" -eq 1 ]; then
    # Display Firefox help, then our help
    TOR_CONTROL_PASSWD=${TOR_CONTROL_PASSWD} ./firefox --class "Tor Browser" \
        -profile TorBrowser/Data/Browser/profile.default --help 2>/dev/null
    tbb_usage
elif [ "$detach" -eq 1 ] ; then
    TOR_CONTROL_PASSWD=${TOR_CONTROL_PASSWD} ./firefox --class "Tor Browser" \
       -profile TorBrowser/Data/Browser/profile.default "${@}" > "$logfile" 2>&1 </dev/null &
    disown "$!"
elif [ "$log_output" -eq 1 -a "$show_output" -eq 1 ]; then
    TOR_CONTROL_PASSWD=${TOR_CONTROL_PASSWD} ./firefox --class "Tor Browser" \
        -profile TorBrowser/Data/Browser/profile.default "${@}" 2>&1 </dev/null | \
        tee "$logfile"
elif [ "$show_output" -eq 1 ]; then
    TOR_CONTROL_PASSWD=${TOR_CONTROL_PASSWD} ./firefox --class "Tor Browser" \
        -profile TorBrowser/Data/Browser/profile.default "${@}" < /dev/null
else
    TOR_CONTROL_PASSWD=${TOR_CONTROL_PASSWD} ./firefox --class "Tor Browser" \
        -profile TorBrowser/Data/Browser/profile.default "${@}" > "$logfile" 2>&1 </dev/null
fi

exit $?
