From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: richard@nod.at From: Richard Weinberger To: kzak@redhat.com Cc: ebiederm@xmission.com, util-linux@vger.kernel.org, davidlohr.bueso@hp.com, Richard Weinberger Subject: [PATCH] nsenter: Allow selecting the uid and gid to be used in the entered userns Date: Thu, 25 Apr 2013 21:11:40 +0200 Message-Id: <1366917100-10581-1-git-send-email-richard@nod.at> List-ID: Using -S (--setuid) and -G (--setgid) one can select the uid/gid which will be used in the entered user namespace. Signed-off-by: Richard Weinberger --- sys-utils/nsenter.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/sys-utils/nsenter.c b/sys-utils/nsenter.c index 106349c..7b2255c 100644 --- a/sys-utils/nsenter.c +++ b/sys-utils/nsenter.c @@ -72,6 +72,8 @@ static void usage(int status) fputs(_(" -n, --net [=] enter network namespace\n"), out); fputs(_(" -p, --pid [=] enter pid namespace\n"), out); fputs(_(" -U, --user [=] enter user namespace\n"), out); + fputs(_(" -S, --setuid set uid in user namespace\n"), out); + fputs(_(" -G, --setgid set gid in user namespace\n"), out); fputs(_(" -r, --root [=] set the root directory\n"), out); fputs(_(" -w, --wd [=] set the working directory\n"), out); fputs(_(" -F, --no-fork do not fork before exec'ing \n"), out); @@ -169,6 +171,8 @@ int main(int argc, char *argv[]) { "net", optional_argument, NULL, 'n' }, { "pid", optional_argument, NULL, 'p' }, { "user", optional_argument, NULL, 'U' }, + { "setuid", required_argument, NULL, 'S' }, + { "setgid", required_argument, NULL, 'G' }, { "root", optional_argument, NULL, 'r' }, { "wd", optional_argument, NULL, 'w' }, { "no-fork", no_argument, NULL, 'F' }, @@ -179,6 +183,10 @@ int main(int argc, char *argv[]) int c, namespaces = 0; bool do_rd = false, do_wd = false; int do_fork = -1; /* unknown yet */ + bool set_uid = false; + bool set_gid = false; + uid_t uid = 0; + gid_t gid = 0; setlocale(LC_MESSAGES, ""); bindtextdomain(PACKAGE, LOCALEDIR); @@ -186,7 +194,7 @@ int main(int argc, char *argv[]) atexit(close_stdout); while ((c = - getopt_long(argc, argv, "hVt:m::u::i::n::p::U::r::w::F", + getopt_long(argc, argv, "hVt:m::u::i::n::p::U::S:G:r::w::F", longopts, NULL)) != -1) { switch (c) { case 'h': @@ -234,6 +242,14 @@ int main(int argc, char *argv[]) else namespaces |= CLONE_NEWUSER; break; + case 'S': + uid = strtoul_or_err(optarg, _("failed to parse uid")); + set_uid = true; + break; + case 'G': + gid = strtoul_or_err(optarg, _("failed to parse gid")); + set_gid = true; + break; case 'F': do_fork = 0; break; @@ -319,5 +335,15 @@ int main(int argc, char *argv[]) execvp(argv[optind], argv + optind); err(EXIT_FAILURE, _("failed to execute %s"), argv[optind]); } + + if (namespaces & CLONE_NEWUSER) { + if (set_uid) + if (setuid(uid) < 0) + err(EXIT_FAILURE, _("setuid failed")); + if (set_gid) + if (setgid(gid) < 0) + err(EXIT_FAILURE, _("setgid failed")); + } + exec_shell(); } -- 1.8.1.4