mustberoot.subr revision 241653
1238438Sdteskeif [ ! "$_MUSTBEROOT_SUBR" ]; then _MUSTBEROOT_SUBR=1 2238438Sdteske# 3238438Sdteske# Copyright (c) 2006-2012 Devin Teske 4238438Sdteske# All Rights Reserved. 5238438Sdteske# 6238438Sdteske# Redistribution and use in source and binary forms, with or without 7238438Sdteske# modification, are permitted provided that the following conditions 8238438Sdteske# are met: 9238438Sdteske# 1. Redistributions of source code must retain the above copyright 10238438Sdteske# notice, this list of conditions and the following disclaimer. 11238438Sdteske# 2. Redistributions in binary form must reproduce the above copyright 12238438Sdteske# notice, this list of conditions and the following disclaimer in the 13238438Sdteske# documentation and/or other materials provided with the distribution. 14238438Sdteske# 15238438Sdteske# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16238438Sdteske# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING BUT NOT LIMITED TO, THE 17238438Sdteske# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18238438Sdteske# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19238438Sdteske# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20238438Sdteske# DAMAGES (INLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21238438Sdteske# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22238438Sdteske# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23238438Sdteske# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24238438Sdteske# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25238438Sdteske# SUCH DAMAGE. 26238438Sdteske# 27238438Sdteske# $FreeBSD: head/usr.sbin/bsdconfig/share/mustberoot.subr 241653 2012-10-17 21:48:45Z dteske $ 28238438Sdteske# 29238438Sdteske############################################################ INCLUDES 30238438Sdteske 31240684SdteskeBSDCFG_SHARE="/usr/share/bsdconfig" 32240684Sdteske. $BSDCFG_SHARE/common.subr || exit 1 33240684Sdteskef_include $BSDCFG_SHARE/dialog.subr 34240684Sdteske 35238438SdteskeBSDCFG_LIBE="/usr/libexec/bsdconfig" 36238438Sdteskef_include_lang $BSDCFG_LIBE/include/messages.subr 37238438Sdteske 38238438Sdteske############################################################ CONFIGURATION 39238438Sdteske# NOTE: These are not able to be overridden/inherited for security purposes. 40238438Sdteske 41238438Sdteske# 42238438Sdteske# Number of tries a user gets to enter his/her password before we log the 43238438Sdteske# sudo(8) failure and exit. 44238438Sdteske# 45238438SdteskePASSWD_TRIES=3 46238438Sdteske 47238438Sdteske# 48238438Sdteske# While in SECURE mode, should authentication as `root' be allowed? Set to 49238438Sdteske# non-NULL to enable authentication as `root', otherwise disabled. 50238438Sdteske# 51238438Sdteske# WARNING: 52238438Sdteske# Unless using a custom sudo(8) configuration, user `root' should not be 53238438Sdteske# allowed because no password is required to become `root' when already `root' 54238438Sdteske# and therefore, any value entered as password will work. 55238438Sdteske# 56238438SdteskeSECURE_ALLOW_ROOT= 57238438Sdteske 58238438Sdteske# 59238438Sdteske# While in SECURE mode, should we divulge (through error message) when the 60238438Sdteske# requested authentication user does not exist? Set to non-NULL to enable, 61238438Sdteske# otherwise a non-existent user is treated like an invalid password. 62238438Sdteske# 63238438SdteskeSECURE_DIVULGE_UNKNOWN_USER= 64238438Sdteske 65238438Sdteske############################################################ FUNCTIONS 66238438Sdteske 67238438Sdteske# f_become_root_via_sudo 68238438Sdteske# 69238438Sdteske# If not running as root, prompt for sudo(8) credentials to become root. 70238438Sdteske# Re-execution of the current program via sudo is automatically handled. 71238438Sdteske# 72238438Sdteske# The following environment variables effect functionality: 73238438Sdteske# 74238438Sdteske# USE_XDIALOG Either NULL or Non-NULL. If given a value will indicate 75238438Sdteske# that Xdialog(1) should be used instead of dialog(1). 76238438Sdteske# 77238438Sdteskef_become_root_via_sudo() 78238438Sdteske{ 79238438Sdteske local msg hline size 80238438Sdteske 81238438Sdteske [ "$( id -u )" = "0" ] && return $SUCCESS 82238438Sdteske 83238438Sdteske f_have sudo || f_die 1 "$msg_must_be_root_to_execute" "$pgm" 84238438Sdteske 85238438Sdteske # 86241653Sdteske # Ask the user if it's OK to become root via sudo(8) and give them 87241653Sdteske # the option to save this preference (by touch(1)ing a file in the 88241653Sdteske # user's $HOME directory). 89241653Sdteske # 90241653Sdteske local checkpath="${HOME%/}/.bsdconfig_uses_sudo" 91241653Sdteske if [ ! -e "$checkpath" ]; then 92241653Sdteske msg=$( printf "$msg_always_try_sudo_when_run_as" "$USER" ) 93241653Sdteske local menu_list=" 94241653Sdteske 'X' '$msg_cancel_exit' 95241653Sdteske '1' '$msg' 96241653Sdteske '2' '$msg_try_sudo_only_this_once' 97241653Sdteske " # END-QUOTE 98241653Sdteske msg=$( printf "$msg_you_are_not_root_but" bsdconfig ) 99241653Sdteske hline="$hline_arrows_tab_enter" 100241653Sdteske size=$( eval f_dialog_menu_size \ 101241653Sdteske \"\$DIALOG_TITLE\" \ 102241653Sdteske \"\$DIALOG_BACKTITLE\" \ 103241653Sdteske \"\$msg\" \ 104241653Sdteske \"\$hline\" \ 105241653Sdteske $menu_list ) 106241653Sdteske 107241653Sdteske local dialog_menu mtag retval 108241653Sdteske dialog_menu=$( eval $DIALOG \ 109241653Sdteske --title \"\$DIALOG_TITLE\" \ 110241653Sdteske --backtitle \"\$DIALOG_BACKTITLE\" \ 111241653Sdteske --hline \"\$hline\" \ 112241653Sdteske --ok-label \"\$msg_ok\" \ 113241653Sdteske --cancel-label \"\$msg_cancel\" \ 114241653Sdteske --menu \"\$msg\" $size \ 115241653Sdteske $menu_list \ 116241653Sdteske 2>&1 >&$DIALOG_TERMINAL_PASSTHRU_FD 117241653Sdteske ) 118241653Sdteske retval=$? 119241653Sdteske setvar DIALOG_MENU_$$ "$dialog_menu" 120241653Sdteske mtag=$( f_dialog_menutag ) 121241653Sdteske 122241653Sdteske [ $retval -eq 0 ] || f_die 123241653Sdteske 124241653Sdteske case "$mtag" in 125241653Sdteske X) # Cancel/Exit 126241653Sdteske f_die ;; 127241653Sdteske 1) # Always try sudo(8) when run as $user 128241653Sdteske local err 129241653Sdteske if ! err=$( touch "$checkpath" 2>&1 ); then 130241653Sdteske f_show_msg "%s" "$err" 131241653Sdteske else 132241653Sdteske f_show_msg "$msg_created_path" "$checkpath" 133241653Sdteske fi 134241653Sdteske esac 135241653Sdteske else 136241653Sdteske # 137241653Sdteske # This user has created the path signing-off on sudo(8)-use 138241653Sdteske # but let's still give them a short/quick/unobtrusive reminder 139241653Sdteske # 140241653Sdteske f_dialog_info "$msg_becoming_root_via_sudo" 141241653Sdteske [ "$USE_XDIALOG" ] || sleep 0.6 142241653Sdteske fi 143241653Sdteske 144241653Sdteske # 145238438Sdteske # Check sudo(8) access before prompting for password. 146238438Sdteske # 147240783Sdteske :| sudo -S -v 2> /dev/null 148238438Sdteske if [ $? -ne $SUCCESS ]; then 149238438Sdteske # 150238438Sdteske # sudo(8) access denied. Prompt for their password. 151238438Sdteske # 152238438Sdteske msg="$msg_please_enter_password" 153238438Sdteske hline="$hline_alnum_punc_tab_enter" 154238438Sdteske size=$( f_dialog_inputbox_size \ 155238438Sdteske "$DIALOG_TITLE" \ 156238438Sdteske "$DIALOG_BACKTITLE" \ 157238438Sdteske "$msg" \ 158238438Sdteske "$hline" ) 159238438Sdteske 160238438Sdteske # 161238438Sdteske # Continue prompting until they either Cancel, succeed 162238438Sdteske # or exceed the number of allowed failures. 163238438Sdteske # 164238438Sdteske local password nfailures=0 retval 165238438Sdteske while [ $nfailures -lt $PASSWD_TRIES ]; do 166238438Sdteske if [ "$USE_XDIALOG" ]; then 167238438Sdteske password=$( $DIALOG \ 168238438Sdteske --title "$DIALOG_TITLE" \ 169238438Sdteske --backtitle "$DIALOG_BACKTITLE" \ 170238438Sdteske --hline "$hline" \ 171238438Sdteske --ok-label "$msg_ok" \ 172238438Sdteske --cancel-label "$msg_cancel" \ 173238438Sdteske --password --inputbox "$msg" $size \ 174240783Sdteske 2>&1 > /dev/null ) 175238438Sdteske retval=$? 176238438Sdteske 177238438Sdteske # Catch X11-related errors 178238438Sdteske [ $retval -eq 255 ] && 179238438Sdteske f_die $retval "$password" 180238438Sdteske else 181240768Sdteske local dialog_inputbox 182240768Sdteske dialog_inputbox=$( $DIALOG \ 183238438Sdteske --title "$DIALOG_TITLE" \ 184238438Sdteske --backtitle "$DIALOG_BACKTITLE" \ 185238438Sdteske --hline "$hline" \ 186238438Sdteske --ok-label "$msg_ok" \ 187238438Sdteske --cancel-label "$msg_cancel" \ 188238438Sdteske --insecure \ 189238438Sdteske --passwordbox "$msg" $size \ 190240768Sdteske 2>&1 >&$DIALOG_TERMINAL_PASSTHRU_FD 191240768Sdteske ) 192238438Sdteske retval=$? 193240768Sdteske setvar DIALOG_INPUTBOX_$$ "$dialog_inputbox" 194238438Sdteske password=$( f_dialog_inputstr ) 195238438Sdteske fi 196238438Sdteske 197238438Sdteske # Exit if the user cancelled. 198238438Sdteske [ $retval -eq $SUCCESS ] || exit $retval 199238438Sdteske 200238438Sdteske # 201238438Sdteske # Validate sudo(8) credentials 202238438Sdteske # 203240783Sdteske sudo -S -v 2> /dev/null <<-EOF 204238438Sdteske $password 205238438Sdteske EOF 206238438Sdteske retval=$? 207238438Sdteske unset password # scrub memory 208238438Sdteske if [ $retval -eq $SUCCESS ]; then 209238438Sdteske # Access granted... 210238438Sdteske break 211238438Sdteske else 212238438Sdteske # Access denied... 213238438Sdteske nfailures=$(( $nfailures + 1 )) 214238438Sdteske 215238438Sdteske # introduce a short delay 216238438Sdteske if [ $nfailures -lt $PASSWD_TRIES ]; then 217238438Sdteske f_dialog_info "$msg_sorry_try_again" 218238438Sdteske sleep 1 219238438Sdteske fi 220238438Sdteske fi 221238438Sdteske done 222238438Sdteske 223238438Sdteske # 224238438Sdteske # If user exhausted number of allowed password tries, log 225238438Sdteske # the security event and exit immediately. 226238438Sdteske # 227238438Sdteske if [ $nfailures -ge $PASSWD_TRIES ]; then 228238438Sdteske msg=$( printf "$msg_nfailed_attempts" "$nfailures" ) 229238438Sdteske logger -p auth.notice -t sudo " " \ 230238438Sdteske "$USER : $msg" \ 231238438Sdteske "; TTY=$(tty)" \ 232238438Sdteske "; PWD=$PWD" \ 233238438Sdteske "; USER=root" \ 234238438Sdteske "; COMMAND=$0" 235238438Sdteske f_die 1 "sudo: $msg" 236238438Sdteske fi 237238438Sdteske fi 238238438Sdteske 239238438Sdteske # Use xauth(1) to grant root the ability to use this X11/SSH session 240238438Sdteske if [ "$USE_XDIALOG" -a "$SSH_CONNECTION" -a "$DISPLAY" ]; then 241238438Sdteske f_have xauth || f_die 1 \ 242238438Sdteske "$msg_no_such_file_or_directory" "$pgm" "xauth" 243238438Sdteske local HOSTNAME displaynum 244238438Sdteske HOSTNAME=$(hostname) 245238438Sdteske displaynum="${DISPLAY#*:}" 246238438Sdteske xauth -f ~/.Xauthority extract - $HOSTNAME/unix:$displaynum \ 247238438Sdteske $HOSTNAME:$displaynum | sudo sh -c 'xauth -ivf \ 248240783Sdteske ~root/.Xauthority merge - > /dev/null 2>&1' 249238438Sdteske fi 250238438Sdteske 251238438Sdteske # Re-execute ourselves with sudo(8) 252238438Sdteske if [ $ARGC -gt 0 ]; then 253238438Sdteske exec sudo "$0" $ARGV 254238438Sdteske else 255238438Sdteske exec sudo "$0" 256238438Sdteske fi 257238438Sdteske exit $? # Never reached unless error 258238438Sdteske} 259238438Sdteske 260238438Sdteske# f_authenticate_some_user 261238438Sdteske# 262238438Sdteske# Only used if running as root and requires X11 (see USE_XDIALOG below). 263238438Sdteske# Prompts the user to enter a username and password to be authenticated via 264238438Sdteske# sudo(8) to proceed. 265238438Sdteske# 266238438Sdteske# The following environment variables effect functionality: 267238438Sdteske# 268238438Sdteske# USE_XDIALOG Either NULL or Non-NULL. If given a value will indicate 269238438Sdteske# that Xdialog(1) should be used instead of dialog(1). 270238438Sdteske# 271238438Sdteskef_authenticate_some_user() 272238438Sdteske{ 273238438Sdteske local msg hline size width height 274238438Sdteske 275238438Sdteske f_have sudo || f_die 1 "$msg_must_be_root_to_execute" "$pgm" 276238438Sdteske 277238438Sdteske # 278238438Sdteske # Secure-mode has been requested. 279238438Sdteske # 280238438Sdteske 281238438Sdteske [ "$USE_XDIALOG" ] || f_die 1 "$msg_secure_mode_requires_x11" 282238438Sdteske [ "$(id -u)" = "0" ] || f_die 1 "$msg_secure_mode_requires_root" 283238438Sdteske 284238438Sdteske # 285238438Sdteske # Prompt for sudo(8) credentials. 286238438Sdteske # 287238438Sdteske 288238438Sdteske msg="$msg_please_enter_username_password" 289238438Sdteske hline="$hline_alnum_punc_tab_enter" 290238438Sdteske size=$( f_xdialog_2inputsbox_size \ 291238438Sdteske "$DIALOG_TITLE" \ 292238438Sdteske "$DIALOG_BACKTITLE" \ 293238438Sdteske "$msg" \ 294238438Sdteske "$field_username" "" \ 295238438Sdteske "$field_password" "" ) 296238438Sdteske width="${size##*[$IFS]}" 297238438Sdteske height="${size%%[$IFS]*}" 298238438Sdteske height=$(( $height + 2 )) # Add height for --password 299238438Sdteske 300238438Sdteske # 301238438Sdteske # Continue prompting until they either Cancel, succeed or exceed the 302238438Sdteske # number of allowed failures. 303238438Sdteske # 304238438Sdteske local user_pass nfailures=0 retval 305238438Sdteske while [ $nfailures -lt $PASSWD_TRIES ]; do 306238438Sdteske user_pass=$( $DIALOG \ 307238438Sdteske --title "$DIALOG_TITLE" \ 308238438Sdteske --backtitle "$DIALOG_BACKTITLE" \ 309238438Sdteske --hline "$hline" \ 310238438Sdteske --ok-label "$msg_ok" \ 311238438Sdteske --cancel-label "$msg_cancel" \ 312238438Sdteske --password --2inputsbox "$msg" \ 313238438Sdteske $height $width \ 314238438Sdteske "$field_username" "" \ 315238438Sdteske "$field_password" "" \ 316240783Sdteske 2>&1 > /dev/null ) 317238438Sdteske retval=$? 318238438Sdteske 319238438Sdteske # Catch X11-related errors 320238438Sdteske [ $retval -eq 255 ] && f_die $retval "$user_pass" 321238438Sdteske 322238438Sdteske # Exit if the user cancelled. 323238438Sdteske [ $retval -eq $SUCCESS ] || exit $retval 324238438Sdteske 325238438Sdteske # 326238438Sdteske # Make sure the user exists and is non-root 327238438Sdteske # 328238438Sdteske local user password 329238438Sdteske user="${user_pass%%/*}" 330238438Sdteske password="${user_pass#*/}" 331238438Sdteske unset user_pass # scrub memory 332238438Sdteske if [ ! "$user" ]; then 333238438Sdteske nfailures=$(( $nfailures + 1 )) 334238438Sdteske f_dialog_msgbox "$msg_no_username" 335238438Sdteske continue 336238438Sdteske fi 337238438Sdteske if [ ! "$SECURE_ALLOW_ROOT" ]; then 338238438Sdteske case "$user" in 339238438Sdteske root|toor) 340238438Sdteske nfailures=$(( $nfailures + 1 )) 341238438Sdteske f_dialog_msgbox "$( printf \ 342238438Sdteske "$msg_user_disallowed" "$user" )" 343238438Sdteske continue 344238438Sdteske esac 345238438Sdteske fi 346238438Sdteske if ! f_quietly id "$user"; then 347238438Sdteske nfailures=$(( $nfailures + 1 )) 348238438Sdteske if [ "$SECURE_DIVULGE_UNKNOWN_USER" ]; then 349238438Sdteske f_dialog_msgbox "$( printf \ 350238438Sdteske "$msg_unknown_user" "$user" )" 351238438Sdteske elif [ $nfailures -lt $PASSWD_TRIES ]; then 352238438Sdteske f_dialog_info "$msg_sorry_try_again" 353238438Sdteske sleep 1 354238438Sdteske fi 355238438Sdteske continue 356238438Sdteske fi 357238438Sdteske 358238438Sdteske # 359238438Sdteske # Validate sudo(8) credentials for given user 360238438Sdteske # 361238438Sdteske su -m "$user" <<-EOF 362238438Sdteske sh <<EOS 363238438Sdteske sudo -k 364240783Sdteske sudo -S -v 2> /dev/null <<EOP 365238438Sdteske $password 366238438Sdteske EOP 367238438Sdteske EOS 368238438Sdteske EOF 369238438Sdteske retval=$? 370238438Sdteske unset user 371238438Sdteske unset password # scrub memory 372238438Sdteske 373238438Sdteske if [ $retval -eq $SUCCESS ]; then 374238438Sdteske # Access granted... 375238438Sdteske break 376238438Sdteske else 377238438Sdteske # Access denied... 378238438Sdteske nfailures=$(( $nfailures + 1 )) 379238438Sdteske 380238438Sdteske # introduce a short delay 381238438Sdteske if [ $nfailures -lt $PASSWD_TRIES ]; then 382238438Sdteske f_dialog_info "$msg_sorry_try_again" 383238438Sdteske sleep 1 384238438Sdteske fi 385238438Sdteske fi 386238438Sdteske done 387238438Sdteske 388238438Sdteske # 389238438Sdteske # If user exhausted number of allowed password tries, log 390238438Sdteske # the security event and exit immediately. 391238438Sdteske # 392238438Sdteske if [ $nfailures -ge $PASSWD_TRIES ]; then 393238438Sdteske msg=$( printf "$msg_nfailed_attempts" "$nfailures" ) 394238438Sdteske logger -p auth.notice -t sudo " " \ 395238438Sdteske "${SUDO_USER:-$USER} : $msg" \ 396238438Sdteske "; TTY=$(tty)" \ 397238438Sdteske "; PWD=$PWD" \ 398238438Sdteske "; USER=root" \ 399238438Sdteske "; COMMAND=$0" 400238438Sdteske f_die 1 "sudo: $message" 401238438Sdteske fi 402238438Sdteske} 403238438Sdteske 404238438Sdteske# f_mustberoot_init 405238438Sdteske# 406238438Sdteske# If not already root, make the switch to root by re-executing ourselves via 407238438Sdteske# sudo(8) using user-supplied credentials. 408238438Sdteske# 409238438Sdteske# The following environment variables effect functionality: 410238438Sdteske# 411238438Sdteske# SECURE Either NULL or Non-NULL. If given a value will indicate 412238438Sdteske# that (while running as root) sudo(8) authentication is 413238438Sdteske# required to proceed. 414238438Sdteske# 415238438Sdteskef_mustberoot_init() 416238438Sdteske{ 417238438Sdteske if [ "$(id -u)" != "0" -a ! "$SECURE" ]; then 418238438Sdteske f_become_root_via_sudo 419238438Sdteske elif [ "$SECURE" ]; then 420238438Sdteske f_authenticate_some_user 421238438Sdteske fi 422238438Sdteske} 423238438Sdteske 424238438Sdteskefi # ! $_MUSTBEROOT_SUBR 425