unsafe-browser 9.29 KB
Newer Older
1
#!/bin/sh
2

3
4
set -e

Tails developers's avatar
Tails developers committed
5
CMD=$(basename ${0})
6
LOCK=/var/lock/${CMD}
Tails developers's avatar
Tails developers committed
7
8

. gettext.sh
9
TEXTDOMAIN="tails"
Tails developers's avatar
Tails developers committed
10
11
export TEXTDOMAIN

12
ROFS=/lib/live/mount/rootfs/filesystem.squashfs
13
14
15
CONF_DIR=/var/lib/unsafe-browser
COW=${CONF_DIR}/cow
CHROOT=${CONF_DIR}/chroot
16
CLEARNET_USER=clearnet
17
18
19

# Import tor_is_working()
. /usr/local/lib/tails-shell-library/tor.sh
20

21
22
23
# Import the TBB_INSTALL, TBB_EXT and TBB_PROFILE variables, and
# exec_firefox(), configure_xulrunner_app_locale() and
# guess_best_tor_browser_locale()
24
25
. /usr/local/lib/tails-shell-library/tor-browser.sh

26
27
. /usr/local/lib/tails-shell-library/chroot-browser.sh

28
29
30
31
32
33
34
35
WARNING_PAGE='/usr/share/doc/tails/website/misc/unsafe_browser_warning'
LANG_CODE="$(echo ${LANG} | head -c 2)"
if [ -r "${WARNING_PAGE}.${LANG_CODE}.html" ]; then
   START_PAGE="${WARNING_PAGE}.${LANG_CODE}.html"
else
   START_PAGE="${WARNING_PAGE}.en.html"
fi

36
37
38
39
if [ -e /var/lib/gdm3/tails.camouflage ]; then
    CAMOUFLAGE=yes
fi

40
cleanup () {
41
    try_cleanup_browser_chroot ${CHROOT} ${COW} ${CLEARNET_USER}
42
43
44
}

error () {
45
46
    local cli_text="${CMD}: `gettext \"error:\"` ${@}"
    local dialog_text="<b><big>`gettext \"Error\"`</big></b>
47

48
${@}"
49
    echo "${cli_text}" >&2
50
    sudo -u ${SUDO_USER} zenity --error --title "" --text "${dialog_text}"
51
52
53
    exit 1
}

54
55
verify_start () {
    # Make sure the user really wants to start the browser
56
    local dialog_msg="<b><big>`gettext \"Do you really want to launch the Unsafe Browser?\"`</big></b>
57

Tails developers's avatar
Tails developers committed
58
`gettext \"Network activity within the Unsafe Browser is <b>not anonymous</b>. Only use the Unsafe Browser if necessary, for example if you have to login or register to activate your Internet connection.\"`"
59
60
61
62
63
64
    local launch="`gettext \"_Launch\"`"
    local exit="`gettext \"_Exit\"`"
    # Since zenity can't set the default button to cancel, we switch the
    # labels and interpret the return value as its negation.
    if sudo -u ${SUDO_USER} zenity --question --title "" --ok-label "${exit}" \
       --cancel-label "${launch}" --text "${dialog_msg}"; then
65
66
67
        exit 0
    fi
}
68

69
70
71
show_start_notification () {
    local title="`gettext \"Starting the Unsafe Browser...\"`"
    local body="`gettext \"This may take a while, so please be patient.\"`"
72
    tails-notify-user "${title}" "${body}" 10000
73
74
}

75
76
77
78
setup_chroot () {
    # Setup a chroot on an aufs "fork" of the filesystem.
    # FIXME: When LXC matures to the point where it becomes a viable option
    # for creating isolated jails, the chroot can be used as its rootfs.
79
80
    echo "* Setting up chroot"

81
82
83
    trap cleanup INT
    trap cleanup EXIT

84
    mkdir -p ${COW} ${CHROOT} && \
85
86
87
    mount -t tmpfs tmpfs ${COW} && \
    mount -t aufs -o noatime,noxino,dirs=${COW}=rw:${ROFS}=rr+wh aufs ${CHROOT} && \
    mount -t proc proc ${CHROOT}/proc && \
Tails developers's avatar
Tails developers committed
88
89
    mount --bind /dev ${CHROOT}/dev || \
    error "`gettext \"Failed to setup chroot.\"`"
90
91
92

    # Workaround for todo/buggy_aufs_vs_unsafe-browser
    chmod -t ${COW}
93
94
}

95
96
set_chroot_browser_name () {
    NAME="${1}"
97
    LOCALE="${2}"
98
    EXT_DIR=${CHROOT}/"${TBB_EXT}"
99
100
    if [ "${LOCALE}" != en-US ]; then
        PACK="${EXT_DIR}/langpack-${LOCALE}@firefox.mozilla.org.xpi"
101
        TOP=browser/chrome
102
        REST=${LOCALE}/locale
103
    else
104
        PACK="${CHROOT}/${TBB_INSTALL}/browser/omni.ja"
105
106
        TOP=chrome
        REST=en-US/locale
107
108
    fi
    TMP=$(mktemp -d)
109
    BRANDING="${TOP}/${REST}/branding/brand.dtd"
110
111
    # Non-zero exit code due to non-standard ZIP archive.
    # The following steps will fail soon if the extraction failed anyway.
112
113
114
    7z x -o"${TMP}" "${PACK}" "${BRANDING}" || true
    sed -i "s/<"'!'"ENTITY\s\+brand\(Full\|Short\)Name.*$/<"'!'"ENTITY brand\1Name \"${NAME}\">/" "${TMP}/${BRANDING}"
    (cd $TMP ; 7z u -tzip "${PACK}" .)
115
116
117
118
    chmod a+r "${PACK}"
    rm -Rf "${TMP}"
}

119
configure_chroot () {
120
121
    echo "* Configuring chroot"

122
123
    # Set the chroot's DNS servers to those obtained through DHCP
    rm -f ${CHROOT}/etc/resolv.conf
124
    for NS in ${IP4_NAMESERVERS}; do
125
126
127
128
        echo "nameserver ${NS}" >> ${CHROOT}/etc/resolv.conf
    done
    chmod a+r ${CHROOT}/etc/resolv.conf

129
    # Remove all addons: some adds proxying, which we don't
130
    # want; some may change the fingerprint compared to a standard
131
    # Firefox install. Note: We cannot use apt-get since we don't ship its
132
133
134
    # lists (#6531). Too bad, APT supports globbing, while dkpg does not.
    dpkg -l 'xul-ext-*' | /bin/grep '^ii' | awk '{print $2}' | \
        xargs chroot ${CHROOT} dpkg --remove
135

136
    # Create a fresh browser profile for the clearnet user
137
138
139
140
    CLEARNET_PROFILE="${CHROOT}"/home/clearnet/.tor-browser/profile.default

    CLEARNET_EXT="${CLEARNET_PROFILE}"/extensions
    mkdir -p "${CLEARNET_EXT}"
141
    cp -Pr "${TBB_PROFILE}"/extensions/langpack-*.xpi "${CLEARNET_EXT}"
142
143
144
145
146

    CLEARNET_PREFS="${CLEARNET_PROFILE}"/preferences/prefs.js
    mkdir -p "$(dirname "${CLEARNET_PREFS}")"

    # Localization
147
148
    BEST_LOCALE="$(guess_best_tor_browser_locale)"
    configure_xulrunner_app_locale "${CLEARNET_PROFILE}" "${BEST_LOCALE}"
149

150
    # Disable proxying in the chroot
151
152
    echo 'pref("network.proxy.type", 0);' >> "${CLEARNET_PREFS}"
    echo 'pref("network.proxy.socks_remote_dns", false);' >>  "${CLEARNET_PREFS}"
153

154
155
156
157
    # Prevent File -> Print or CTRL+P from causing the browser to hang
    # for several minutes while trying to communicate with CUPS, since
    # access to port 631 isn't allowed through.
    echo 'pref("print.postscript.cups.enabled", false);' >> "${CLEARNET_PREFS}"
158
159
    # Hide "Get Addons" in Add-ons manager
    echo 'user_pref("extensions.getAddons.showPane", false);' >> "${CLEARNET_PREFS}"
160

161
    # Set the name (e.g. window title) of the browser
162
    set_chroot_browser_name "`gettext \"Unsafe Browser\"`" "${BEST_LOCALE}"
163

164
165
    # Set start page to something that explains what's going on
    echo 'user_pref("browser.startup.homepage", "'${START_PAGE}'");' >> \
166
        "${CLEARNET_PREFS}"
167
168
169
170
171
172
173
174
175
176
177
178
179
    BROWSER_CHROME="${CLEARNET_PROFILE}/chrome/userChrome.css"
    mkdir -p "$(dirname "${BROWSER_CHROME}")"
    cat > ${BROWSER_CHROME} << EOF
/* Required, do not remove */
@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");

/* Hide TorBrowser Health Report and its configuration option */
#appmenu_healthReport,
#dataChoicesTab,
#healthReport

{display: none !important}
EOF
180
181

    # Remove all bookmarks
182
    rm -f ${CHROOT}/"${TBB_PROFILE}"/bookmarks.html
183
184
    rm -f ${CLEARNET_PROFILE}/bookmarks.html
    rm -f ${CLEARNET_PROFILE}/places.sqlite
185
186

    chown -R clearnet:clearnet ${CHROOT}/home/clearnet/.tor-browser
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202

    # Set a scary theme (except if we're using Windows
    # camouflage). Note that the tails-activate-win8-theme script that
    # we may run below requires that the browser profile is writable
    # by the user running the script (i.e. clearnet).
    if [ -z "${CAMOUFLAGE}" ]; then
        cat >> "${CLEARNET_PREFS}" <<EOF
pref("lightweightThemes.isThemeSelected", true);
pref("lightweightThemes.usedThemes", "[{\"id\":\"1\",\"name\":\"Unsafe Browser\",\"headerURL\":\"file:///usr/share/pixmaps/red_dot.png\",\"footerURL\":\"file:///usr/share/pixmaps/red_dot.png\",\"textcolor\":\"#FFFFFF\",\"accentcolor\":\"#CC0000\",\"updateDate\":0,\"installDate\":0}]");
EOF
    else
        # The camouflage activation script requires a dbus server for
        # properly configuring GNOME, so we start one in the chroot
        chroot ${CHROOT} sudo -H -u clearnet sh -c 'eval `dbus-launch --auto-syntax`; tails-activate-win8-theme' || :
    fi

203
204
}

205
run_browser_in_chroot () {
206
    # Start the browser in the chroot
207
208
    echo "* Starting Unsafe Browser"

209
    sudo -u ${SUDO_USER} xhost +SI:localuser:${CLEARNET_USER} 2>/dev/null
210
211
212
213
    chroot ${CHROOT} sudo -u ${CLEARNET_USER} /bin/sh -c \
        '. /usr/local/lib/tails-shell-library/tor-browser.sh && \
         exec_firefox -DISPLAY=:0.0 \
                      -profile /home/clearnet/.tor-browser/profile.default'
214
    sudo -u ${SUDO_USER} xhost -SI:localuser:${CLEARNET_USER} 2>/dev/null
215
216
}

217
218
219
show_shutdown_notification () {
    local title="`gettext \"Shutting down the Unsafe Browser...\"`"
    local body="`gettext \"This may take a while, and you may not restart the Unsafe Browser until it is properly shut down.\"`"
220
    tails-notify-user "${title}" "${body}" 10000
221
222
}

223
224
225
226
227
maybe_restart_tor () {
    # Restart Tor if it's not working (a captive portal may have prevented
    # Tor from bootstrapping, and a restart is the fastest way to get
    # wheels turning)
    if ! tor_is_working; then
228
        echo "* Restarting Tor"
229
230
        restart-tor
        if ! service tor status >/dev/null; then
231
232
            error "`gettext \"Failed to restart Tor.\"`"
        fi
233
234
    fi
}
235

236
237
238
239
240
241
# Prevent multiple instances of the script.
exec 9>${LOCK}
if ! flock -x -n 9; then
    error "`gettext \"Another Unsafe Browser is currently running, or being cleaned up. Please retry in a while.\"`"
fi

242
# Get the DNS servers that was obtained from NetworkManager, if any...
243
244
245
246
247
248
249
250
NM_ENV=/var/lib/NetworkManager/env
if [ -r "${NM_ENV}" ]; then
    . ${NM_ENV}
fi
# ... otherwise fail.
# FIXME: Or would it make sense to fallback to Google's DNS or OpenDNS?
# Some stupid captive portals may allow DNS to any host, but chances are
# that only the portal's DNS would forward to the login page.
251
if [ -z "${IP4_NAMESERVERS}" ]; then
Tails developers's avatar
Tails developers committed
252
    error "`gettext \"No DNS server was obtained through DHCP or manually configured in NetworkManager.\"`"
253
254
fi

255
verify_start
256
show_start_notification
257
258
setup_chroot
configure_chroot
259
260
run_browser_in_chroot
show_shutdown_notification
261
maybe_restart_tor
262
263

exit 0