From 699dfdd0ea25d01177f603461473f4e0c88f7378 Mon Sep 17 00:00:00 2001 From: Daniel Shahaf Date: Thu, 6 Feb 2020 12:47:39 +0000 Subject: 45385: Add a test for 'zmodload -Fa' preemptively disabling ("blacklisting"?) features. --- ChangeLog | 5 +++++ Test/V01zmodload.ztst | 14 ++++++++++++++ 2 files changed, 19 insertions(+) diff --git a/ChangeLog b/ChangeLog index d13fb6e0f..ea80ad5bc 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2020-02-06 Daniel Shahaf + + * 45385: Test/V01zmodload.ztst: Add a test for 'zmodload -Fa' + preemptively disabling ("blacklisting"?) features. + 2020-02-06 dana * unposted: Config/version.mk: Update for 5.7.1-test-3 diff --git a/Test/V01zmodload.ztst b/Test/V01zmodload.ztst index 1bd8c1900..6a4e34d2d 100644 --- a/Test/V01zmodload.ztst +++ b/Test/V01zmodload.ztst @@ -348,6 +348,20 @@ ?(eval):6: unknown function: systell ?(eval):9: file descriptor out of range + $ZTST_testdir/../Src/zsh -fc ' + zmodload zsh/zutil + zmodload -Fal zsh/zutil | grep parse + zmodload -u zsh/zutil + # + zmodload -Fa zsh/zutil -b:zregexparse + zmodload zsh/zutil + zmodload -Fal zsh/zutil | grep parse >&2 + ' +0:zmodload -Fa can disable features from being loaded +>b:zparseopts +>b:zregexparse +?b:zparseopts + %clean eval "$deps" -- cgit v1.2.3 From 8037462895b4de98528a6b56c2f35d606150d3f3 Mon Sep 17 00:00:00 2001 From: dana Date: Fri, 7 Feb 2020 14:05:48 -0600 Subject: unposted: _zip: Recognise '--' --- ChangeLog | 4 ++++ Completion/Unix/Command/_zip | 6 +++--- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/ChangeLog b/ChangeLog index ea80ad5bc..b71c1bd8c 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,7 @@ +2020-02-07 dana + + * unposted: Completion/Unix/Command/_zip: Recognise '--' + 2020-02-06 Daniel Shahaf * 45385: Test/V01zmodload.ztst: Add a test for 'zmodload -Fa' diff --git a/Completion/Unix/Command/_zip b/Completion/Unix/Command/_zip index 1b1b6c315..bc9aab1a5 100644 --- a/Completion/Unix/Command/_zip +++ b/Completion/Unix/Command/_zip @@ -82,7 +82,7 @@ case $service in '*:file:->files' && ret=0 ;; unzip) - _arguments -C -s \ + _arguments -C -s -S \ '(-Z)-M[page output]' \ - unzip \ '(-f -u -l -t -z -d -p)-c[extract files to stdout including file names]' \ @@ -130,7 +130,7 @@ esac [[ $state == zipinfo ]] && uzi="-Z[zipinfo mode]" if [[ $service == zipinfo ]] || [[ -n $uzi ]]; then - _arguments -C -s \ + _arguments -C -s -S \ $uzi \ '(-2 -s -m -l -v -h -t -T -z)-1[filenames only]' \ '(-1 -s -m -l -v -T)-2[just filenames but allow -h/-t/-z]' \ @@ -170,7 +170,7 @@ case $state in fi 2>/dev/null if [[ $zipfile != $_zip_cache_name ]]; then _zip_cache_name="$zipfile" - _zip_cache_list=( ${(f)"$(zipinfo -1 $_zip_cache_name)"} ) + _zip_cache_list=( ${(f)"$(zipinfo -1 -- $_zip_cache_name)"} ) fi _wanted files expl 'file from archive' \ _multi_parts / _zip_cache_list && return -- cgit v1.2.3 From dd523255cc67780f2e073136d7f44978f96534a7 Mon Sep 17 00:00:00 2001 From: dana Date: Fri, 14 Feb 2020 09:42:12 -0600 Subject: 45423: _su: Improve arg handling, shell look-ups Differences from ML post: * Properly fix escaping issue with $usr (needs unescaped first) * Make $shell emptiness check easier to read (per feedback) --- ChangeLog | 5 +++++ Completion/Unix/Command/_su | 45 +++++++++++++++++++++++++++++++++------------ 2 files changed, 38 insertions(+), 12 deletions(-) diff --git a/ChangeLog b/ChangeLog index b71c1bd8c..f23a956b0 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2020-02-14 dana + + * 45423 (tweaked): Completion/Unix/Command/_su: Improve arg + handling, shell look-ups + 2020-02-07 dana * unposted: Completion/Unix/Command/_zip: Recognise '--' diff --git a/Completion/Unix/Command/_su b/Completion/Unix/Command/_su index 900905632..032f867f4 100644 --- a/Completion/Unix/Command/_su +++ b/Completion/Unix/Command/_su @@ -9,36 +9,44 @@ local shell usr (( $words[(i)-(l|-login)] < CURRENT )) || args=( '-[use a login shell]' ) case $OSTYPE in linux*) + # Some of these options only apply to util-linux, not shadow-utils args=( -S $args - '(-c --command --session-command *)'{-c,--command=}'[pass command to shell]:command string:_cmdstring' + '(-c --command --session-command *)'{-c+,--command=}'[pass command to shell]:command string:_cmdstring' "(-c --command *)--session-command=[pass command to shell and don't create a new session]:command string:_cmdstring" '(--fast -f)'{-f,--fast}'[pass -f to shell]' '(-l --login -m -p --preserve-environment)'{-l,--login}'[use a login shell]' '(-l --login -m -p --preserve-environment)'{-m,-p,--preserve-environment}"[don't reset environment]" - '(-s --shell)'{-s,--shell=}'[run the specified shell]:shell:->shells' + '(-s --shell)'{-s+,--shell=}'[run the specified shell]:shell:->shells' '(-)--help[display help information]' '(-)--version[display version information]' ) - (( EUID )) || args+=( - '(-g --group)'{-g,--group=}'[specify primary group]:group:_groups' - \*{-G,--supp-group=}'[specify supplemental group]:group:_groups' + (( $#_comp_priv_prefix || EUID == 0 )) && args+=( + '(-g --group)'{-g+,--group=}'[specify primary group]:group:_groups' + \*{-G+,--supp-group=}'[specify supplemental group]:group:_groups' ) first="(--help --version)${first#???}" ;; *bsd*|darwin*|dragonfly*) args+=( - '-c[use settings from specified login class]:class' '-f[if the invoked shell is csh, prevent it from reading .cshrc]' '(-m)-l[use a login shell]' "(-l)-m[don't reset environment]" ) ;| + *bsd*|dragonfly*) + args+=( + '-c+[use settings from specified login class]:class' + ) + ;| freebsd*) args+=( '-s[set the MAC label]' ) ;; openbsd*) args+=( - '(-K)-a[specify authentication type]:authentication type' + # See login.conf(5) + '(-K)-a+[specify authentication type]:authentication type:( + activ chpass crypto lchpass passwd radius reject skey snk token yubikey + )' '(-a)-K[shorthand for -a passwd]' - '-s[run the specified shell]:shell:->shells' + '-s+[run the specified shell]:shell:->shells' '-L[loop until login succeeds]' ) ;; @@ -57,13 +65,26 @@ fi _arguments $args ${(e)first} "*:shell arguments:= ->rest" && return -usr=${line[norm]/--/root} -if (( $#opt_args[(i)-(s|-shell)] )); then +usr=${${(Q)line[norm]}/--/root} +# OpenBSD supports appending a log-in method to the user name, as in usr:radius +[[ $OSTYPE == openbsd* ]] && usr=${usr%:*} + +# Normal users generally don't appear in passwd on macOS; try the Directory +# Service first +if [[ $OSTYPE == darwin* ]] && (( $+commands[dscl] )); then + shell=${"$( + _call_program shells dscl . -read /Users/${(q)usr} UserShell + )"#UserShell: } +fi + +if [[ -n $shell ]]; then + : # Found above +elif (( ${#${(@M)args:#*-s[+\[]*:*}} && $#opt_args[(i)-(s|-shell)] )); then shell=${(v)opt_args[(i)-(s|-shell)]} elif (( ${+commands[getent]} )); then - shell="${$(_call_program shells getent passwd $usr)##*:}" + shell="${$(_call_program shells getent passwd ${(q)usr})##*:}" else - shell="${${(M@)${(@f)$( Date: Fri, 14 Feb 2020 15:55:52 -0600 Subject: unposted: V01zmodload: Fix failing test from workers/45385 --- ChangeLog | 3 +++ Test/V01zmodload.ztst | 6 ++++-- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/ChangeLog b/ChangeLog index f23a956b0..2e76e04a7 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,8 @@ 2020-02-14 dana + * unposted: Test/V01zmodload.ztst: Fix failing test from + workers/45385 + * 45423 (tweaked): Completion/Unix/Command/_su: Improve arg handling, shell look-ups diff --git a/Test/V01zmodload.ztst b/Test/V01zmodload.ztst index 6a4e34d2d..55c3c314b 100644 --- a/Test/V01zmodload.ztst +++ b/Test/V01zmodload.ztst @@ -348,7 +348,9 @@ ?(eval):6: unknown function: systell ?(eval):9: file descriptor out of range - $ZTST_testdir/../Src/zsh -fc ' + $ZTST_testdir/../Src/zsh -fc " + MODULE_PATH=${(q)MODULE_PATH} + # zmodload zsh/zutil zmodload -Fal zsh/zutil | grep parse zmodload -u zsh/zutil @@ -356,7 +358,7 @@ zmodload -Fa zsh/zutil -b:zregexparse zmodload zsh/zutil zmodload -Fal zsh/zutil | grep parse >&2 - ' + " 0:zmodload -Fa can disable features from being loaded >b:zparseopts >b:zregexparse -- cgit v1.2.3 From 24e993db62cf146fb76ebcf677a4a7aa3766fc74 Mon Sep 17 00:00:00 2001 From: Sam Foxman Date: Sun, 22 Dec 2019 17:30:28 -0500 Subject: Drop privileges securely --- Src/options.c | 161 +++++++++++++++++++++++++++++++++++++++++++--------------- configure.ac | 4 +- 2 files changed, 124 insertions(+), 41 deletions(-) diff --git a/Src/options.c b/Src/options.c index 48c14c179..328cf318b 100644 --- a/Src/options.c +++ b/Src/options.c @@ -577,6 +577,7 @@ int bin_setopt(char *nam, char **args, UNUSED(Options ops), int isun) { int action, optno, match = 0; + int retval = 0; /* With no arguments or options, display options. */ if (!*args) { @@ -604,18 +605,28 @@ bin_setopt(char *nam, char **args, UNUSED(Options ops), int isun) inittyptab(); return 1; } - if(!(optno = optlookup(*args))) + if(!(optno = optlookup(*args))) { zwarnnam(nam, "no such option: %s", *args); - else if(dosetopt(optno, action, 0, opts)) - zwarnnam(nam, "can't change option: %s", *args); + retval = 1; + } else { + retval = !!dosetopt(optno, action, 0, opts); + if (retval) { + zwarnnam(nam, "can't change option: %s", *args); + } + } break; } else if(**args == 'm') { match = 1; } else { - if (!(optno = optlookupc(**args))) + if (!(optno = optlookupc(**args))) { zwarnnam(nam, "bad option: -%c", **args); - else if(dosetopt(optno, action, 0, opts)) - zwarnnam(nam, "can't change option: -%c", **args); + retval = 1; + } else { + retval = !!dosetopt(optno, action, 0, opts); + if (retval) { + zwarnnam(nam, "can't change option: -%c", **args); + } + } } } args++; @@ -625,10 +636,15 @@ bin_setopt(char *nam, char **args, UNUSED(Options ops), int isun) if (!match) { /* Not globbing the arguments -- arguments are simply option names. */ while (*args) { - if(!(optno = optlookup(*args++))) + if(!(optno = optlookup(*args++))) { zwarnnam(nam, "no such option: %s", args[-1]); - else if(dosetopt(optno, !isun, 0, opts)) - zwarnnam(nam, "can't change option: %s", args[-1]); + retval = 1; + } else { + retval = !!dosetopt(optno, !isun, 0, opts); + if (retval) { + zwarnnam(nam, "can't change option: %s", args[-1]); + } + } } } else { /* Globbing option (-m) set. */ @@ -651,7 +667,8 @@ bin_setopt(char *nam, char **args, UNUSED(Options ops), int isun) tokenize(s); if (!(pprog = patcompile(s, PAT_HEAPDUP, NULL))) { zwarnnam(nam, "bad pattern: %s", *args); - continue; + retval = 1; + break; } /* Loop over expansions. */ scanmatchtable(optiontab, pprog, 0, 0, OPT_ALIAS, @@ -660,7 +677,7 @@ bin_setopt(char *nam, char **args, UNUSED(Options ops), int isun) } } inittyptab(); - return 0; + return retval; } /* Identify an option name */ @@ -769,37 +786,101 @@ dosetopt(int optno, int value, int force, char *new_opts) return -1; } else if(optno == PRIVILEGED && !value) { /* unsetting PRIVILEGED causes the shell to make itself unprivileged */ -#ifdef HAVE_SETUID - int ignore_err; - errno = 0; - /* - * Set the GID first as if we set the UID to non-privileged it - * might be impossible to restore the GID. - * - * Some OSes (possibly no longer around) have been known to - * fail silently the first time, so we attempt the change twice. - * If it fails we are guaranteed to pick this up the second - * time, so ignore the first time. - * - * Some versions of gcc make it hard to ignore the results the - * first time, hence the following. (These are probably not - * systems that require the doubled calls.) - */ - ignore_err = setgid(getgid()); - (void)ignore_err; - ignore_err = setuid(getuid()); - (void)ignore_err; - if (setgid(getgid())) { - zwarn("failed to change group ID: %e", errno); - return -1; - } else if (setuid(getuid())) { - zwarn("failed to change user ID: %e", errno); - return -1; + + int skip_setuid = 0; + int skip_setgid = 0; + +#if defined(HAVE_GETEGID) && defined(HAVE_SETGID) && defined(HAVE_GETUID) + int orig_egid = getegid(); +#endif + +#if defined(HAVE_GETEUID) && defined(HAVE_GETUID) + if (geteuid() == getuid()) { + skip_setuid = 1; + } +#endif + +#if defined(HAVE_GETEGID) && defined(HAVE_GETGID) + if (getegid() == getgid()) { + skip_setgid = 1; } +#endif + + if (!skip_setgid) { + int setgid_err; +#ifdef HAVE_SETRESGID + setgid_err = setresgid(getgid(), getgid(), getgid()); +#elif defined(HAVE_SETREGID) +#if defined(HAVE_GETEGID) && defined(HAVE_SETGID) && defined(HAVE_GETUID) + setgid_err = setregid(getgid(), getgid()); #else - zwarn("setuid not available"); - return -1; -#endif /* not HAVE_SETUID */ + zwarnnam("unsetopt", + "PRIVILEGED: can't drop privileges; setregid available, but cannot check if saved gid changed"); + return -1; +#endif +#else + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresgid and setregid not available"); + return -1; +#endif + if (setgid_err) { + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change group ID: %e", errno); + return -1; + } + } + + if (!skip_setuid) { +#if defined(HAVE_GETEUID) && defined(HAVE_SETUID) + int orig_euid = geteuid(); +#endif + int setuid_err; +#if defined(HAVE_GETEUID) && defined(HAVE_INITGROUPS) && defined(HAVE_GETPWUID) + if (geteuid() == 0) { + struct passwd *pw = getpwuid(getuid()); + if (pw == NULL) { + zwarnnam("unsetopt", "can't drop privileges; failed to get user information for uid %d: %e", + getuid(), errno); + return -1; + } + if (initgroups(pw->pw_name, pw->pw_gid)) { + zwarnnam("unsetopt", "can't drop privileges; failed to set supplementary group list: %e", errno); + return -1; + } + } +#endif + +#ifdef HAVE_SETRESUID + setuid_err = setresuid(getuid(), getuid(), getuid()); +#elif defined(HAVE_SETREUID) +#if defined(HAVE_GETEUID) && defined(HAVE_SETUID) && defined(HAVE_GETUID) + setuid_err = setreuid(getuid(), getuid()); +#else + zwarnnam("unsetopt", + "PRIVILEGED: can't drop privileges; setreuid available, but cannot check if saved uid changed"); + return -1; +#endif +#else + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresuid and setreuid not available"); + return -1; +#endif + if (setuid_err) { + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change user ID: %e", errno); + return -1; + } +#if defined(HAVE_GETEUID) && defined(HAVE_SETUID) && defined(HAVE_GETUID) + if (getuid() != 0 && !setuid(orig_euid)) { + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; was able to restore the euid"); + return -1; + } +#endif + } + +#if defined(HAVE_GETEGID) && defined(HAVE_SETGID) && defined(HAVE_GETUID) + if (getuid() != 0 && !skip_setgid && !setgid(orig_egid)) { + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; was able to restore the egid"); + return -1; + } +#endif + #ifdef JOB_CONTROL } else if (!force && optno == MONITOR && value) { if (new_opts[optno] == value) diff --git a/configure.ac b/configure.ac index c8885cac5..2474c270e 100644 --- a/configure.ac +++ b/configure.ac @@ -1310,7 +1310,9 @@ AC_CHECK_FUNCS(strftime strptime mktime timelocal \ inet_aton inet_pton inet_ntop \ getlogin getpwent getpwnam getpwuid getgrgid getgrnam \ initgroups nis_list \ - setuid seteuid setreuid setresuid setsid \ + getuid setuid seteuid setreuid setresuid setsid \ + getgid setgid setegid setregid setresgid \ + geteuid getegid \ memcpy memmove strstr strerror strtoul \ getrlimit getrusage \ setlocale \ -- cgit v1.2.3 From 8250c5c168f07549ed646e6848e6dda118271e23 Mon Sep 17 00:00:00 2001 From: Daniel Shahaf Date: Thu, 26 Dec 2019 09:16:19 +0000 Subject: Improve PRIVILEGED fixes MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit - Fix retval handling in bin_setopt() - Don't skip_setuid / skip_setgid. It's not our place to optimize away noops (that might not even _be_ noops; they might change the saved uid…). - Remove HAVE_* guard checks around functions that are used unguarded elsewhere. - Use bsd-setres_id.c from OpenSSH to provide setresuid() / setresgid() everywhere, and thus simplify the ifdef soup. Fix some preëxisting bugs in the macro definitions of setuid() (do we still need that one?). - Fix zwarning() format codes for variadic arguments type safety - Restored a comment from HEAD - Fix failure modes around initgroups() - Compared privilege restoration code with OpenSSH's permanently_drop_uid() and updated as needed - Add E01 PRIVILEGED sanity checks --- Src/openssh_bsd_setres_id.c | 129 ++++++++++++++++++++++++++++++++++++++ Src/options.c | 148 ++++++++++++++++++++------------------------ Src/zsh.mdd | 3 +- Src/zsh_system.h | 94 +++++++++++++++++++++++----- Test/E01options.ztst | 15 +++++ configure.ac | 5 +- 6 files changed, 292 insertions(+), 102 deletions(-) create mode 100644 Src/openssh_bsd_setres_id.c diff --git a/Src/openssh_bsd_setres_id.c b/Src/openssh_bsd_setres_id.c new file mode 100644 index 000000000..65e91a40c --- /dev/null +++ b/Src/openssh_bsd_setres_id.c @@ -0,0 +1,129 @@ +/* + * Copyright (c) 2012 Darren Tucker (dtucker at zip com au). + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +/* + * openssh_bsd_setres_id.c - setresuid() and setresgid() wrappers + * + * This file is part of zsh, the Z shell. + * + * It is based on the file openbsd-compat/bsd-setres_id.c in OpenSSH 7.9p1, + * which is subject to the copyright notice above. The zsh modifications are + * licensed as follows: + * + * Copyright (c) 2019 Daniel Shahaf + * All rights reserved. + * + * Permission is hereby granted, without written agreement and without + * license or royalty fees, to use, copy, modify, and distribute this + * software and to distribute modified versions of this software for any + * purpose, provided that the above copyright notice and the following + * two paragraphs appear in all copies of this software. + * + * In no event shall Daniel Shahaf or the Zsh Development Group be liable + * to any party for direct, indirect, special, incidental, or consequential + * damages arising out of the use of this software and its documentation, + * even if Daniel Shahaf and the Zsh Development Group have been advised of + * the possibility of such damage. + * + * Daniel Shahaf and the Zsh Development Group specifically disclaim any + * warranties, including, but not limited to, the implied warranties of + * merchantability and fitness for a particular purpose. The software + * provided hereunder is on an "as is" basis, and Daniel Shahaf and the + * Zsh Development Group have no obligation to provide maintenance, + * support, updates, enhancements, or modifications. + * + */ + + +#include + +#include +#include +#include + +#include "zsh.mdh" + +#if defined(ZSH_IMPLEMENT_SETRESGID) || defined(BROKEN_SETRESGID) +int +setresgid(gid_t rgid, gid_t egid, gid_t sgid) +{ + int ret = 0, saved_errno; + + if (rgid != sgid) { + errno = ENOSYS; + return -1; + } +#if defined(ZSH_HAVE_NATIVE_SETREGID) && !defined(BROKEN_SETREGID) + if (setregid(rgid, egid) < 0) { + saved_errno = errno; + zwarnnam("setregid", "to gid %L: %e", (long)rgid, errno); + errno = saved_errno; + ret = -1; + } +#else + if (setegid(egid) < 0) { + saved_errno = errno; + zwarnnam("setegid", "to gid %L: %e", (long)(unsigned int)egid, errno); + errno = saved_errno; + ret = -1; + } + if (setgid(rgid) < 0) { + saved_errno = errno; + zwarnnam("setgid", "to gid %L: %e", (long)rgid, errno); + errno = saved_errno; + ret = -1; + } +#endif + return ret; +} +#endif + +#if defined(ZSH_IMPLEMENT_SETRESUID) || defined(BROKEN_SETRESUID) +int +setresuid(uid_t ruid, uid_t euid, uid_t suid) +{ + int ret = 0, saved_errno; + + if (ruid != suid) { + errno = ENOSYS; + return -1; + } +#if defined(ZSH_HAVE_NATIVE_SETREUID) && !defined(BROKEN_SETREUID) + if (setreuid(ruid, euid) < 0) { + saved_errno = errno; + zwarnnam("setreuid", "to uid %L: %e", (long)ruid, errno); + errno = saved_errno; + ret = -1; + } +#else + +# ifndef SETEUID_BREAKS_SETUID + if (seteuid(euid) < 0) { + saved_errno = errno; + zwarnnam("seteuid", "to uid %L: %e", (long)euid, errno); + errno = saved_errno; + ret = -1; + } +# endif + if (setuid(ruid) < 0) { + saved_errno = errno; + zwarnnam("setuid", "to uid %L: %e", (long)ruid, errno); + errno = saved_errno; + ret = -1; + } +#endif + return ret; +} +#endif diff --git a/Src/options.c b/Src/options.c index 328cf318b..425e27dc2 100644 --- a/Src/options.c +++ b/Src/options.c @@ -607,25 +607,21 @@ bin_setopt(char *nam, char **args, UNUSED(Options ops), int isun) } if(!(optno = optlookup(*args))) { zwarnnam(nam, "no such option: %s", *args); - retval = 1; - } else { - retval = !!dosetopt(optno, action, 0, opts); - if (retval) { - zwarnnam(nam, "can't change option: %s", *args); - } + retval |= 1; + } else if (dosetopt(optno, action, 0, opts)) { + zwarnnam(nam, "can't change option: %s", *args); + retval |= 1; } break; } else if(**args == 'm') { match = 1; } else { - if (!(optno = optlookupc(**args))) { + if (!(optno = optlookupc(**args))) { zwarnnam(nam, "bad option: -%c", **args); - retval = 1; - } else { - retval = !!dosetopt(optno, action, 0, opts); - if (retval) { - zwarnnam(nam, "can't change option: -%c", **args); - } + retval |= 1; + } else if (dosetopt(optno, action, 0, opts)) { + zwarnnam(nam, "can't change option: -%c", **args); + retval |= 1; } } } @@ -638,12 +634,10 @@ bin_setopt(char *nam, char **args, UNUSED(Options ops), int isun) while (*args) { if(!(optno = optlookup(*args++))) { zwarnnam(nam, "no such option: %s", args[-1]); - retval = 1; - } else { - retval = !!dosetopt(optno, !isun, 0, opts); - if (retval) { - zwarnnam(nam, "can't change option: %s", args[-1]); - } + retval |= 1; + } else if (dosetopt(optno, !isun, 0, opts)) { + zwarnnam(nam, "can't change option: %s", args[-1]); + retval |= 1; } } } else { @@ -667,7 +661,7 @@ bin_setopt(char *nam, char **args, UNUSED(Options ops), int isun) tokenize(s); if (!(pprog = patcompile(s, PAT_HEAPDUP, NULL))) { zwarnnam(nam, "bad pattern: %s", *args); - retval = 1; + retval |= 1; break; } /* Loop over expansions. */ @@ -787,100 +781,92 @@ dosetopt(int optno, int value, int force, char *new_opts) } else if(optno == PRIVILEGED && !value) { /* unsetting PRIVILEGED causes the shell to make itself unprivileged */ - int skip_setuid = 0; - int skip_setgid = 0; - -#if defined(HAVE_GETEGID) && defined(HAVE_SETGID) && defined(HAVE_GETUID) - int orig_egid = getegid(); -#endif + /* If set, return -1 so lastval will be non-zero. */ + int failed = 0; -#if defined(HAVE_GETEUID) && defined(HAVE_GETUID) - if (geteuid() == getuid()) { - skip_setuid = 1; - } +#ifdef HAVE_SETUID + const int orig_euid = geteuid(); #endif + const int orig_egid = getegid(); -#if defined(HAVE_GETEGID) && defined(HAVE_GETGID) - if (getegid() == getgid()) { - skip_setgid = 1; - } -#endif - - if (!skip_setgid) { - int setgid_err; -#ifdef HAVE_SETRESGID - setgid_err = setresgid(getgid(), getgid(), getgid()); -#elif defined(HAVE_SETREGID) -#if defined(HAVE_GETEGID) && defined(HAVE_SETGID) && defined(HAVE_GETUID) - setgid_err = setregid(getgid(), getgid()); -#else - zwarnnam("unsetopt", - "PRIVILEGED: can't drop privileges; setregid available, but cannot check if saved gid changed"); + /* + * Set the GID first as if we set the UID to non-privileged it + * might be impossible to restore the GID. + */ + { +#ifndef HAVE_SETRESGID + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresgid() and friends not available"); return -1; -#endif #else - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresgid and setregid not available"); - return -1; -#endif + int setgid_err; + setgid_err = setresgid(getgid(), getgid(), getgid()); if (setgid_err) { zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change group ID: %e", errno); return -1; } +#endif } - if (!skip_setuid) { -#if defined(HAVE_GETEUID) && defined(HAVE_SETUID) - int orig_euid = geteuid(); -#endif + /* Set the UID second. */ + { +#ifndef HAVE_SETRESUID + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresuid() and friends not available"); + return -1; +#else int setuid_err; -#if defined(HAVE_GETEUID) && defined(HAVE_INITGROUPS) && defined(HAVE_GETPWUID) + +# ifdef HAVE_INITGROUPS + /* Set the supplementary groups list. */ if (geteuid() == 0) { struct passwd *pw = getpwuid(getuid()); if (pw == NULL) { - zwarnnam("unsetopt", "can't drop privileges; failed to get user information for uid %d: %e", - getuid(), errno); - return -1; - } - if (initgroups(pw->pw_name, pw->pw_gid)) { + zwarnnam("unsetopt", "can't drop privileges; failed to get user information for uid %L: %e", + (long)getuid(), errno); + failed = 1; + } else if (initgroups(pw->pw_name, pw->pw_gid)) { zwarnnam("unsetopt", "can't drop privileges; failed to set supplementary group list: %e", errno); return -1; } + } else if (getuid() != 0 && + (geteuid() != getuid() || orig_egid != getegid())) { + zwarnnam("unsetopt", "PRIVILEGED: supplementary group list not changed due to lack of permissions: EUID=%L", + (long)geteuid()); + failed = 1; } -#endif +# else + /* initgroups() isn't in POSIX. If it's not available on the system, + * we silently skip it. */ +# endif -#ifdef HAVE_SETRESUID setuid_err = setresuid(getuid(), getuid(), getuid()); -#elif defined(HAVE_SETREUID) -#if defined(HAVE_GETEUID) && defined(HAVE_SETUID) && defined(HAVE_GETUID) - setuid_err = setreuid(getuid(), getuid()); -#else - zwarnnam("unsetopt", - "PRIVILEGED: can't drop privileges; setreuid available, but cannot check if saved uid changed"); - return -1; -#endif -#else - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresuid and setreuid not available"); - return -1; -#endif if (setuid_err) { zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change user ID: %e", errno); return -1; } -#if defined(HAVE_GETEUID) && defined(HAVE_SETUID) && defined(HAVE_GETUID) - if (getuid() != 0 && !setuid(orig_euid)) { - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; was able to restore the euid"); - return -1; - } #endif } -#if defined(HAVE_GETEGID) && defined(HAVE_SETGID) && defined(HAVE_GETUID) - if (getuid() != 0 && !skip_setgid && !setgid(orig_egid)) { +#ifdef HAVE_SETGID + if (getuid() != 0 && orig_egid != getegid() && + (setgid(orig_egid) != -1 || setegid(orig_egid) != -1)) { zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; was able to restore the egid"); return -1; } #endif +#ifdef HAVE_SETUID + if (getuid() != 0 && orig_euid != geteuid() && + (setuid(orig_euid) != -1 || seteuid(orig_euid) != -1)) { + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; was able to restore the euid"); + return -1; + } +#endif + + if (failed) { + /* A warning message has been printed. */ + return -1; + } + #ifdef JOB_CONTROL } else if (!force && optno == MONITOR && value) { if (new_opts[optno] == value) diff --git a/Src/zsh.mdd b/Src/zsh.mdd index 3e5788af5..9bcaccae5 100644 --- a/Src/zsh.mdd +++ b/Src/zsh.mdd @@ -13,7 +13,8 @@ objects="builtin.o compat.o cond.o context.o \ exec.o glob.o hashtable.o hashnameddir.o \ hist.o init.o input.o jobs.o lex.o linklist.o loop.o math.o \ mem.o module.o options.o params.o parse.o pattern.o prompt.o signals.o \ -signames.o sort.o string.o subst.o text.o utils.o watch.o" +signames.o sort.o string.o subst.o text.o utils.o watch.o \ +openssh_bsd_setres_id.o" headers="../config.h zsh_system.h zsh.h sigcount.h signals.h \ prototypes.h hashtable.h ztype.h" diff --git a/Src/zsh_system.h b/Src/zsh_system.h index 85e198f2e..161b073b4 100644 --- a/Src/zsh_system.h +++ b/Src/zsh_system.h @@ -468,30 +468,90 @@ struct timespec { # define setpgrp setpgid #endif -/* can we set the user/group id of a process */ +/* compatibility wrappers */ -#ifndef HAVE_SETUID +/* Our strategy is as follows: + * + * - Ensure that either setre[ug]id() or set{e,}[ug]id() is available. + * - If setres[ug]id() are missing, provide them in terms of either + * setre[ug]id() or set{e,}[ug]id(), whichever is available. + * - Provide replacement setre[ug]id() or set{e,}[ug]id() if they are not + * available natively. + * + * There isn't a circular dependency because, right off the bat, we check that + * there's an end condition, and #error out otherwise. + */ +#if !defined(HAVE_SETREUID) && !(defined(HAVE_SETEUID) && defined(HAVE_SETUID)) + /* + * If you run into this error, you have two options: + * - Teach zsh how to do the equivalent of setreuid() on your system + * - Remove support for PRIVILEGED option, and then remove the #error. + */ +# error "Don't know how to change UID" +#endif +#if !defined(HAVE_SETREGID) && !(defined(HAVE_SETEGID) && defined(HAVE_SETGID)) + /* See above comment. */ +# error "Don't know how to change GID" +#endif + +/* Provide setresuid(). */ +#ifndef HAVE_SETRESUID +int setresuid(uid_t, uid_t, uid_t); +# define HAVE_SETRESUID +# define ZSH_IMPLEMENT_SETRESUID # ifdef HAVE_SETREUID -# define setuid(X) setreuid(X,X) -# define setgid(X) setregid(X,X) -# define HAVE_SETUID +# define ZSH_HAVE_NATIVE_SETREUID # endif #endif -/* can we set the effective user/group id of a process */ +/* Provide setresgid(). */ +#ifndef HAVE_SETRESGID +int setresgid(gid_t, gid_t, gid_t); +# define HAVE_SETRESGID +# define ZSH_IMPLEMENT_SETRESGID +# ifdef HAVE_SETREGID +# define ZSH_HAVE_NATIVE_SETREGID +# endif +#endif +/* Provide setreuid(). */ +#ifndef HAVE_SETREUID +# define setreuid(X, Y) setresuid((X), (Y), -1) +# define HAVE_SETREUID +#endif + +/* Provide setregid(). */ +#ifndef HAVE_SETREGID +# define setregid(X, Y) setresgid((X), (Y), -1) +# define HAVE_SETREGID +#endif + +/* Provide setuid(). */ +/* ### TODO: Either remove this (this function has been standard since 1985), + * ### or rewrite this without multiply-evaluating the argument */ +#ifndef HAVE_SETUID +# define setuid(X) setreuid((X), (X)) +# define HAVE_SETUID +#endif + +/* Provide setgid(). */ +#ifndef HAVE_SETGID +/* ### TODO: Either remove this (this function has been standard since 1985), + * ### or rewrite this without multiply-evaluating the argument */ +# define setgid(X) setregid((X), (X)) +# define HAVE_SETGID +#endif + +/* Provide seteuid(). */ #ifndef HAVE_SETEUID -# ifdef HAVE_SETREUID -# define seteuid(X) setreuid(-1,X) -# define setegid(X) setregid(-1,X) -# define HAVE_SETEUID -# else -# ifdef HAVE_SETRESUID -# define seteuid(X) setresuid(-1,X,-1) -# define setegid(X) setresgid(-1,X,-1) -# define HAVE_SETEUID -# endif -# endif +# define seteuid(X) setreuid(-1, (X)) +# define HAVE_SETEUID +#endif + +/* Provide setegid(). */ +#ifndef HAVE_SETEGID +# define setegid(X) setregid(-1, (X)) +# define HAVE_SETEGID #endif #ifdef HAVE_SYS_RESOURCE_H diff --git a/Test/E01options.ztst b/Test/E01options.ztst index c4b101bdb..680f49082 100644 --- a/Test/E01options.ztst +++ b/Test/E01options.ztst @@ -1391,3 +1391,18 @@ F:Regression test for workers/41811 ?(anon):4: `break' active at end of function scope ?(anon):4: `break' active at end of function scope ?(anon):4: `break' active at end of function scope + +# There are further tests for PRIVILEGED in P01privileged.ztst. + if [[ -o privileged ]]; then + unsetopt privileged + fi + unsetopt privileged +0:PRIVILEGED sanity check: unsetting is idempotent +F:If this test fails at the first unsetopt, refer to P01privileged.ztst. + + if [[ -o privileged ]]; then + (( UID != EUID )) + else + (( UID == EUID )) + fi +0:PRIVILEGED sanity check: default value is correct diff --git a/configure.ac b/configure.ac index 2474c270e..f2d65ecfc 100644 --- a/configure.ac +++ b/configure.ac @@ -1310,9 +1310,8 @@ AC_CHECK_FUNCS(strftime strptime mktime timelocal \ inet_aton inet_pton inet_ntop \ getlogin getpwent getpwnam getpwuid getgrgid getgrnam \ initgroups nis_list \ - getuid setuid seteuid setreuid setresuid setsid \ - getgid setgid setegid setregid setresgid \ - geteuid getegid \ + setuid seteuid setreuid setresuid setsid \ + setgid setegid setregid setresgid \ memcpy memmove strstr strerror strtoul \ getrlimit getrusage \ setlocale \ -- cgit v1.2.3 From 26d02efa7a9b0a6b32e1a8bbc6aca6c544b94211 Mon Sep 17 00:00:00 2001 From: dana Date: Sun, 29 Dec 2019 02:41:11 +0000 Subject: Improve PRIVILEGED fixes (again) * Pass RGID instead of passwd GID to initgroups() * Clean up #ifdefs, avoid unnecessary checks * Flatten conditions --- Src/options.c | 92 ++++++++++++++++++++++++++++------------------------------- 1 file changed, 43 insertions(+), 49 deletions(-) diff --git a/Src/options.c b/Src/options.c index 425e27dc2..e9577c863 100644 --- a/Src/options.c +++ b/Src/options.c @@ -781,91 +781,85 @@ dosetopt(int optno, int value, int force, char *new_opts) } else if(optno == PRIVILEGED && !value) { /* unsetting PRIVILEGED causes the shell to make itself unprivileged */ +/* For simplicity's sake, require both setresgid() and setresuid() up-front. */ +#if !defined(HAVE_SETRESGID) + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresgid() and friends not available"); + return -1; +#elif !defined(HAVE_SETRESUID) + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresuid() and friends not available"); + return -1; +#else /* If set, return -1 so lastval will be non-zero. */ int failed = 0; - -#ifdef HAVE_SETUID const int orig_euid = geteuid(); -#endif const int orig_egid = getegid(); /* * Set the GID first as if we set the UID to non-privileged it * might be impossible to restore the GID. */ - { -#ifndef HAVE_SETRESGID - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresgid() and friends not available"); + if (setresgid(getgid(), getgid(), getgid())) { + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change group ID: %e", errno); return -1; -#else - int setgid_err; - setgid_err = setresgid(getgid(), getgid(), getgid()); - if (setgid_err) { - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change group ID: %e", errno); - return -1; - } -#endif } - /* Set the UID second. */ - { -#ifndef HAVE_SETRESUID - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresuid() and friends not available"); - return -1; -#else - int setuid_err; - # ifdef HAVE_INITGROUPS - /* Set the supplementary groups list. */ - if (geteuid() == 0) { - struct passwd *pw = getpwuid(getuid()); - if (pw == NULL) { - zwarnnam("unsetopt", "can't drop privileges; failed to get user information for uid %L: %e", - (long)getuid(), errno); - failed = 1; - } else if (initgroups(pw->pw_name, pw->pw_gid)) { - zwarnnam("unsetopt", "can't drop privileges; failed to set supplementary group list: %e", errno); - return -1; - } - } else if (getuid() != 0 && - (geteuid() != getuid() || orig_egid != getegid())) { - zwarnnam("unsetopt", "PRIVILEGED: supplementary group list not changed due to lack of permissions: EUID=%L", - (long)geteuid()); + /* Set the supplementary groups list. + * + * Note that on macOS, FreeBSD, and possibly some other platforms, + * initgroups() resets the EGID to its second argument (see setgroups(2) for + * details). This has the potential to leave the EGID in an unexpected + * state. However, it seems common in other projects that do this dance to + * simply re-use the same GID that's going to become the EGID anyway, in + * which case it doesn't matter. That's what we do here. It's therefore + * possible, in some probably uncommon cases, that the shell ends up not + * having the privileges of the RUID user's primary/passwd group. */ + if (geteuid() == 0) { + struct passwd *pw = getpwuid(getuid()); + if (pw == NULL) { + zwarnnam("unsetopt", "can't drop privileges; failed to get user information for uid %L: %e", + (long)getuid(), errno); failed = 1; + /* This may behave strangely in the unlikely event that the same user + * name appears with multiple UIDs in the passwd database */ + } else if (initgroups(pw->pw_name, getgid())) { + zwarnnam("unsetopt", "can't drop privileges; failed to set supplementary group list: %e", errno); + return -1; } + } else if (getuid() != 0 && + (geteuid() != getuid() || orig_egid != getegid())) { + zwarnnam("unsetopt", "PRIVILEGED: supplementary group list not changed due to lack of permissions: EUID=%L", + (long)geteuid()); + failed = 1; + } # else - /* initgroups() isn't in POSIX. If it's not available on the system, - * we silently skip it. */ + /* initgroups() isn't in POSIX. If it's not available on the system, + * we silently skip it. */ # endif - setuid_err = setresuid(getuid(), getuid(), getuid()); - if (setuid_err) { - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change user ID: %e", errno); - return -1; - } -#endif + /* Set the UID second. */ + if (setresuid(getuid(), getuid(), getuid())) { + zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change user ID: %e", errno); + return -1; } -#ifdef HAVE_SETGID if (getuid() != 0 && orig_egid != getegid() && (setgid(orig_egid) != -1 || setegid(orig_egid) != -1)) { zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; was able to restore the egid"); return -1; } -#endif -#ifdef HAVE_SETUID if (getuid() != 0 && orig_euid != geteuid() && (setuid(orig_euid) != -1 || seteuid(orig_euid) != -1)) { zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; was able to restore the euid"); return -1; } -#endif if (failed) { /* A warning message has been printed. */ return -1; } +#endif /* HAVE_SETRESGID && HAVE_SETRESUID */ #ifdef JOB_CONTROL } else if (!force && optno == MONITOR && value) { -- cgit v1.2.3 From 4ce66857b71b40a0661df3780ff557f2b0f4cb13 Mon Sep 17 00:00:00 2001 From: dana Date: Sun, 29 Dec 2019 02:43:14 +0000 Subject: Clean up error-message white space --- Src/options.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) diff --git a/Src/options.c b/Src/options.c index e9577c863..08ba71917 100644 --- a/Src/options.c +++ b/Src/options.c @@ -783,10 +783,12 @@ dosetopt(int optno, int value, int force, char *new_opts) /* For simplicity's sake, require both setresgid() and setresuid() up-front. */ #if !defined(HAVE_SETRESGID) - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresgid() and friends not available"); + zwarnnam("unsetopt", + "PRIVILEGED: can't drop privileges; setresgid() and friends not available"); return -1; #elif !defined(HAVE_SETRESUID) - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; setresuid() and friends not available"); + zwarnnam("unsetopt", + "PRIVILEGED: can't drop privileges; setresuid() and friends not available"); return -1; #else /* If set, return -1 so lastval will be non-zero. */ @@ -799,7 +801,9 @@ dosetopt(int optno, int value, int force, char *new_opts) * might be impossible to restore the GID. */ if (setresgid(getgid(), getgid(), getgid())) { - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change group ID: %e", errno); + zwarnnam("unsetopt", + "PRIVILEGED: can't drop privileges; failed to change group ID: %e", + errno); return -1; } @@ -817,18 +821,22 @@ dosetopt(int optno, int value, int force, char *new_opts) if (geteuid() == 0) { struct passwd *pw = getpwuid(getuid()); if (pw == NULL) { - zwarnnam("unsetopt", "can't drop privileges; failed to get user information for uid %L: %e", + zwarnnam("unsetopt", + "can't drop privileges; failed to get user information for uid %L: %e", (long)getuid(), errno); failed = 1; /* This may behave strangely in the unlikely event that the same user * name appears with multiple UIDs in the passwd database */ } else if (initgroups(pw->pw_name, getgid())) { - zwarnnam("unsetopt", "can't drop privileges; failed to set supplementary group list: %e", errno); + zwarnnam("unsetopt", + "can't drop privileges; failed to set supplementary group list: %e", + errno); return -1; } } else if (getuid() != 0 && (geteuid() != getuid() || orig_egid != getegid())) { - zwarnnam("unsetopt", "PRIVILEGED: supplementary group list not changed due to lack of permissions: EUID=%L", + zwarnnam("unsetopt", + "PRIVILEGED: supplementary group list not changed due to lack of permissions: EUID=%L", (long)geteuid()); failed = 1; } @@ -839,19 +847,23 @@ dosetopt(int optno, int value, int force, char *new_opts) /* Set the UID second. */ if (setresuid(getuid(), getuid(), getuid())) { - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; failed to change user ID: %e", errno); + zwarnnam("unsetopt", + "PRIVILEGED: can't drop privileges; failed to change user ID: %e", + errno); return -1; } if (getuid() != 0 && orig_egid != getegid() && (setgid(orig_egid) != -1 || setegid(orig_egid) != -1)) { - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; was able to restore the egid"); + zwarnnam("unsetopt", + "PRIVILEGED: can't drop privileges; was able to restore the egid"); return -1; } if (getuid() != 0 && orig_euid != geteuid() && (setuid(orig_euid) != -1 || seteuid(orig_euid) != -1)) { - zwarnnam("unsetopt", "PRIVILEGED: can't drop privileges; was able to restore the euid"); + zwarnnam("unsetopt", + "PRIVILEGED: can't drop privileges; was able to restore the euid"); return -1; } -- cgit v1.2.3 From b15bd4aa590db8087d1e8f2eb1af2874f5db814d Mon Sep 17 00:00:00 2001 From: dana Date: Sat, 28 Dec 2019 20:45:55 -0600 Subject: Add unsetopt/PRIVILEGED tests --- Test/E01options.ztst | 10 ++- Test/P01privileged.ztst | 197 ++++++++++++++++++++++++++++++++++++++++++++++++ Test/README | 1 + 3 files changed, 207 insertions(+), 1 deletion(-) create mode 100644 Test/P01privileged.ztst diff --git a/Test/E01options.ztst b/Test/E01options.ztst index 680f49082..cfe2c75cc 100644 --- a/Test/E01options.ztst +++ b/Test/E01options.ztst @@ -74,7 +74,6 @@ # HASH_LIST_ALL ) # PRINT_EXIT_STATUS haven't worked out what this does yet, although # Bart suggested a fix. -# PRIVILEGED (similar to GLOBAL_RCS) # RCS ( " " " " ) # SH_OPTION_LETTERS even I found this too dull to set up a test for # SINGLE_COMMAND kills shell @@ -95,6 +94,15 @@ %test + # setopt should move on to the next operation in the face of an error, but + # preserve the >0 return code + unsetopt aliases + setopt not_a_real_option aliases && return 2 + print -r - $options[aliases] +0:setopt error handling +?(eval):setopt:4: no such option: not_a_real_option +>on + alias echo='print foo' unsetopt aliases # use eval else aliases are all parsed at start diff --git a/Test/P01privileged.ztst b/Test/P01privileged.ztst new file mode 100644 index 000000000..c54112bb6 --- /dev/null +++ b/Test/P01privileged.ztst @@ -0,0 +1,197 @@ +# This file contains tests related to the PRIVILEGED option. In order to run, +# it requires that the test process itself have super-user privileges (or that +# one of the environment variables described below be set). This can be achieved +# via, e.g., `sudo make check TESTNUM=P`. +# +# Optionally, the environment variables ZSH_TEST_UNPRIVILEGED_UID and/or +# ZSH_TEST_UNPRIVILEGED_GID may be set to UID:EUID or GID:EGID pairs, where the +# two IDs in each pair are different, non-0 IDs valid on the system being used +# to run the tests. (The UIDs must both be non-0 to effectively test downgrading +# of privileges, and they must be non-matching to test auto-enabling of +# PRIVILEGED and to ensure that disabling PRIVILEGED correctly resets the saved +# UID. Technically GID 0 is not special, but for simplicity's sake we apply the +# same requirements here.) +# +# If either of the aforementioned environment variables is not set, the test +# script will try to pick the first two >0 IDs from the passwd/group databases +# on the current system. +# +# If either variable is set, the tests will run, but they will likely fail +# without super-user privileges. + +%prep + + # Mind your empty lines here. The logic in this %prep section is somewhat + # complex compared to most others; to avoid lots of nested/duplicated + # conditions we need to make sure that this all gets executed as a single + # function from which we can return early + [[ $EUID == 0 || -n $ZSH_TEST_UNPRIVILEGED_UID$ZSH_TEST_UNPRIVILEGED_GID ]] || { + ZTST_unimplemented='PRIVILEGED tests require super-user privileges (or env var)' + return 1 + } + (( $+commands[perl] )) || { # @todo Eliminate this dependency with a C wrapper? + ZTST_unimplemented='PRIVILEGED tests require Perl' + return 1 + } + grep -qE '#define HAVE_SETRES?UID' $ZTST_testdir/../config.h || { + ZTST_unimplemented='PRIVILEGED tests require setreuid()/setresuid()' + return 1 + } + # + ruid= euid= rgid= egid= + # + if [[ -n $ZSH_TEST_UNPRIVILEGED_UID ]]; then + ruid=${ZSH_TEST_UNPRIVILEGED_UID%%:*} + euid=${ZSH_TEST_UNPRIVILEGED_UID##*:} + else + print -ru$ZTST_fd 'Selecting unprivileged UID:EUID pair automatically' + local tmp=$( getent passwd 2> /dev/null || < /etc/passwd ) + # Note: Some awks require -v and its argument to be separate + ruid=$( awk -F: '$3 > 0 { print $3; exit; }' <<< $tmp ) + euid=$( awk -F: -v u=$ruid '$3 > u { print $3; exit; }' <<< $tmp ) + fi + # + if [[ -n $ZSH_TEST_UNPRIVILEGED_GID ]]; then + rgid=${ZSH_TEST_UNPRIVILEGED_GID%%:*} + egid=${ZSH_TEST_UNPRIVILEGED_GID##*:} + else + print -ru$ZTST_fd 'Selecting unprivileged GID:EGID pair automatically' + local tmp=$( getent group 2> /dev/null || < /etc/group ) + # Note: Some awks require -v and its argument to be separate + rgid=$( awk -F: '$3 > 0 { print $3; exit; }' <<< $tmp ) + egid=$( awk -F: -v g=$rgid '$3 > g { print $3; exit; }' <<< $tmp ) + fi + # + [[ $ruid/$euid == <1->/<1-> && $ruid != $euid ]] || ruid= euid= + [[ $rgid/$egid == <1->/<1-> && $rgid != $egid ]] || rgid= egid= + # + [[ -n $ruid && -n $euid ]] || { + ZTST_unimplemented='PRIVILEGED tests require unprivileged UID:EUID' + return 1 + } + [[ -n $rgid || -n $egid ]] || { + ZTST_unimplemented='PRIVILEGED tests require unprivileged GID:EGID' + return 1 + } + # + print -ru$ZTST_fd \ + "Using unprivileged UID $ruid, EUID $euid, GID $rgid, EGID $egid" + # + # Execute process with specified UID and EUID + # $1 => Real UID + # $2 => Effective UID + # $3 => Real GID + # $4 => Effective GID + # $5 ... => Command + args to execute (must NOT be a shell command string) + re_exec() { + perl -e ' + die("re_exec: not enough arguments") unless (@ARGV >= 5); + my ($ruid, $euid, $rgid, $egid, @cmd) = @ARGV; + foreach my $id ($ruid, $euid, $rgid, $egid) { + die("re_exec: invalid ID: $id") unless ($id =~ /^(-1|\d+)$/a); + } + $< = 0 + $ruid if ($ruid >= 0); + $> = 0 + $euid if ($euid >= 0); + $( = 0 + $rgid if ($rgid >= 0); + $) = 0 + $egid if ($egid >= 0); + exec(@cmd); + die("re_exec: exec failed: $!"); + ' -- "$@" + } + # + # Convenience wrapper for re_exec to call `zsh -c` + # -* ... => (optional) Command-line options to zsh + # $1 => Real UID + # $2 => Effective UID + # $3 => Real GID + # $4 => Effective GID + # $5 ... => zsh command string; multiple strings are joined by \n + re_zsh() { + local -a opts + while [[ $1 == -[A-Za-z-]* ]]; do + opts+=( $1 ) + shift + done + re_exec "$1" "$2" "$3" "$4" $ZTST_exe $opts -fc \ + "MODULE_PATH=${(q)MODULE_PATH}; ${(F)@[5,-1]}" + } + # + # Return one or more random unused UIDs + # $1 ... => Names of parameters to store UIDs in + get_unused_uid() { + while (( $# )); do + local i_=0 uid_= + until [[ -n $uid_ ]]; do + (( ++i_ > 99 )) && return 1 + uid_=$RANDOM + id $uid_ &> /dev/null || break + uid_= + done + : ${(P)1::=$uid_} + shift + done + } + +%test + + re_zsh $ruid $ruid -1 -1 'echo $UID/$EUID $options[privileged]' + re_zsh $euid $euid -1 -1 'echo $UID/$EUID $options[privileged]' + re_zsh $ruid $euid -1 -1 'echo $UID/$EUID $options[privileged]' +0q:PRIVILEGED automatically enabled when RUID != EUID +>$ruid/$ruid off +>$euid/$euid off +>$ruid/$euid on + + re_zsh -1 -1 $rgid $rgid 'echo $GID/$EGID $options[privileged]' + re_zsh -1 -1 $egid $egid 'echo $GID/$EGID $options[privileged]' + re_zsh -1 -1 $rgid $egid 'echo $GID/$EGID $options[privileged]' +0q:PRIVILEGED automatically enabled when RGID != EGID +>$rgid/$rgid off +>$egid/$egid off +>$rgid/$egid on + + re_zsh $ruid $euid -1 -1 'unsetopt privileged; echo $UID/$EUID' +0q:EUID set to RUID after disabling PRIVILEGED +*?zsh:unsetopt:1: PRIVILEGED: supplementary group list not changed * +*?zsh:unsetopt:1: can't change option: privileged +>$ruid/$ruid + + re_zsh 0 $euid -1 -1 'unsetopt privileged && echo $UID/$EUID' +0:RUID/EUID set to 0/0 when privileged after disabling PRIVILEGED +>0/0 + + re_zsh $ruid $euid -1 -1 "unsetopt privileged; UID=$euid" || + re_zsh $ruid $euid -1 -1 "unsetopt privileged; EUID=$euid" +1:not possible to regain EUID when unprivileged after disabling PRIVILEGED +*?zsh:unsetopt:1: PRIVILEGED: supplementary group list not changed * +*?zsh:unsetopt:1: can't change option: privileged +*?zsh:1: failed to change user ID: * +*?zsh:unsetopt:1: PRIVILEGED: supplementary group list not changed * +*?zsh:unsetopt:1: can't change option: privileged +*?zsh:1: failed to change effective user ID: * + + re_zsh -1 -1 $rgid $egid 'unsetopt privileged && echo $GID/$EGID' +0q:EGID set to RGID after disabling PRIVILEGED +>$rgid/$rgid + +# This test also confirms that we can't revert to the original EUID's primary +# GID, which initgroups() may reset the EGID to on some systems + re_zsh $ruid 0 $rgid 0 'unsetopt privileged; GID=0' || + re_zsh $ruid 0 $rgid 0 'unsetopt privileged; EGID=0' +1:not possible to regain EGID when unprivileged after disabling PRIVILEGED +*?zsh:1: failed to change group ID: * +*?zsh:1: failed to change effective group ID: * + + local rruid + grep -qF '#define HAVE_INITGROUPS' $ZTST_testdir/../config.h || { + ZTST_skip='initgroups() not available' + return 1 + } + get_unused_uid rruid || { + ZTST_skip="Can't get unused UID" + return 1 + } + re_zsh $rruid 0 -1 -1 'unsetopt privileged' +1:getpwuid() fails with non-existent RUID and 0 EUID +*?zsh:unsetopt:1: can't drop privileges; failed to get user information * +*?zsh:unsetopt:1: can't change option: privileged diff --git a/Test/README b/Test/README index d012277ce..726d68e72 100644 --- a/Test/README +++ b/Test/README @@ -6,6 +6,7 @@ scripts names: C: shell commands with special syntax D: substititution E: options + P: privileged (needs super-user privileges) V: modules W: builtin interactive commands and constructs X: line editing -- cgit v1.2.3 From 048f40b68b05fdd5f3f8d60cda4e69fce2611331 Mon Sep 17 00:00:00 2001 From: dana Date: Tue, 31 Dec 2019 03:41:28 -0600 Subject: Update NEWS/README --- NEWS | 18 ++++++++++++++++-- README | 11 +++++++++-- 2 files changed, 25 insertions(+), 4 deletions(-) diff --git a/NEWS b/NEWS index af59cb4e6..964e1633f 100644 --- a/NEWS +++ b/NEWS @@ -4,8 +4,22 @@ CHANGES FROM PREVIOUS VERSIONS OF ZSH Note also the list of incompatibilities in the README file. -Changes since 5.7.1 -------------------- +Changes since 5.7.1-test-3 +-------------------------- + +CVE-2019-20044: When unsetting the PRIVILEGED option, the shell sets its +effective user and group IDs to match their respective real IDs. On some +platforms (including Linux and macOS, but not FreeBSD), when the RUID and +EUID were both non-zero, it was possible to regain the shell's former +privileges by e.g. assigning to the EUID or EGID parameter. In the course +of investigating this issue, it was also found that the setopt built-in +did not correctly report errors when unsetting the option, which +prevented users from handling them as the documentation recommended. +setopt now returns non-zero if it is unable to safely drop privileges. +[ Reported by Sam Foxman . ] + +Changes from 5.7.1 to 5.7.1-test-3 +---------------------------------- The zsh/zutil module's zparseopts builtin learnt an -F option to abort parsing when an unrecognised option-like parameter is encountered. diff --git a/README b/README index a3701abe5..7f1dd5f92 100644 --- a/README +++ b/README @@ -5,8 +5,9 @@ THE Z SHELL (ZSH) Version ------- -This is version 5.8 of the shell. This is a stable release. There are -a few visible improvements since 5.7 as well as many bugfixes. +This is version 5.8 of the shell. This is a security and feature release. +There are a few visible improvements since 5.7, as well as many bugfixes. +All zsh installations are encouraged to upgrade as soon as possible. Note in particular the changes highlighted under "Incompatibilities since 5.7.1" below. See NEWS for more information. @@ -56,6 +57,12 @@ This only affects you if you override that function in your dotfiles. The cd and chdir builtins no longer interpret operands like -1 and +2 as stack entries when POSIX_CD is enabled. +Dropping privileges with `unsetopt privileged` may fail (with an error +message) on some older and uncommon platforms due to library dependency +changes made in the course of fixing CVE-2019-20044. Please report this +to the zsh-workers mailing list if your system is affected. See NEWS for +more. + Incompatibilities between 5.6.2 and 5.7.1 ----------------------------------------- -- cgit v1.2.3 From 4bec892059cf3e95ab256c3fcbc85daaa648c2d9 Mon Sep 17 00:00:00 2001 From: dana Date: Fri, 14 Feb 2020 11:26:58 -0600 Subject: CVE-2019-20044: Update change log for preceding commits --- ChangeLog | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/ChangeLog b/ChangeLog index 2e76e04a7..b66514c37 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,11 @@ 2020-02-14 dana + * Sam Foxman, Daniel Shahaf, dana: CVE-2019-20044: NEWS, + README, Src/openssh_bsd_setres_id.c, Src/options.c, Src/zsh.mdd, + Src/zsh_system.h, Test/E01options.ztst, Test/P01privileged.ztst, + Test/README, configure.ac: Fix insecure dropping of privileges + when unsetting PRIVILEGED option + * unposted: Test/V01zmodload.ztst: Fix failing test from workers/45385 -- cgit v1.2.3 From 77d203f3fbbd76386bf197f9776269a1de580bb5 Mon Sep 17 00:00:00 2001 From: dana Date: Fri, 14 Feb 2020 11:30:56 -0600 Subject: unposted: Release 5.8 --- ChangeLog | 2 ++ Config/version.mk | 4 ++-- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/ChangeLog b/ChangeLog index b66514c37..8d7dfc169 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,7 @@ 2020-02-14 dana + * unposted: Config/version.mk: Update for 5.8 + * Sam Foxman, Daniel Shahaf, dana: CVE-2019-20044: NEWS, README, Src/openssh_bsd_setres_id.c, Src/options.c, Src/zsh.mdd, Src/zsh_system.h, Test/E01options.ztst, Test/P01privileged.ztst, diff --git a/Config/version.mk b/Config/version.mk index 2ddb92388..264c11c6b 100644 --- a/Config/version.mk +++ b/Config/version.mk @@ -27,5 +27,5 @@ # This must also serve as a shell script, so do not add spaces around the # `=' signs. -VERSION=5.7.1-test-3 -VERSION_DATE='February 6, 2020' +VERSION=5.8 +VERSION_DATE='February 14, 2020' -- cgit v1.2.3