From 568c26861b47a3f1b7138bf4cbfb37bf0d43896d Mon Sep 17 00:00:00 2001
From: Gerhard Rieger <gerhard@dest-unreach.org>
Date: Sun, 26 Nov 2023 14:08:33 +0100
Subject: [PATCH] Procan: print saved set-user-ID
---
CHANGES | 3 +++
config.h.in | 6 ++++++
configure.ac | 2 ++
procan.c | 20 ++++++++++++++++++++
4 files changed, 31 insertions(+)
diff --git a/CHANGES b/CHANGES
index 22574fe..a68fa3b 100644
--- a/CHANGES
+++ b/CHANGES
@@ -98,6 +98,9 @@ Features:
POSIXMQ is now an alias for POSIXMQ-BIDIRECTIONAL. It can also be used
in unidirectional context.
+ Procan uses getresuid() and getresgid() when available, to determine
+ the saved set-user-ID.
+
Building:
Disabling certain features during configure could break build process.
diff --git a/config.h.in b/config.h.in
index 410576b..39061f1 100644
--- a/config.h.in
+++ b/config.h.in
@@ -162,6 +162,12 @@
/* Define if you have the clock_gettime function */
#undef HAVE_CLOCK_GETTIME
+/* Define if you have the getresuid function */
+#undef HAVE_GETRESUID
+
+/* Define if you have the getresgid function */
+#undef HAVE_GETRESGID
+
/* Define if you have the strtoll function */
#undef HAVE_STRTOLL
diff --git a/configure.ac b/configure.ac
index bdc2fd0..da5d4e3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1722,6 +1722,8 @@ AC_CHECK_PROTOTYPE_LIB(gettimeofday)
AC_CHECK_FUNC(clock_gettime, AC_DEFINE(HAVE_CLOCK_GETTIME), AC_CHECK_LIB(rt, clock_gettime, [LIBS="-lrt $LIBS"; AC_DEFINE(HAVE_CLOCK_GETTIME)]))
+AC_CHECK_FUNCS(getresuid getresgid)
+
dnl Search for flock()
# with Linux it's in libc, with AIX in libbsd
AC_CHECK_FUNC(flock, AC_DEFINE(HAVE_FLOCK),
diff --git a/procan.c b/procan.c
index 22dd5e4..f51751c 100644
--- a/procan.c
+++ b/procan.c
@@ -187,10 +187,30 @@ int procan(FILE *outfile) {
fprintf(outfile, "process group id if fg process / stderr = "F_pid"\n", Tcgetpgrp(2));
/* process owner, groups */
+#if HAVE_GETRESUID
+ {
+ uid_t ruid, euid, suid;
+ getresuid(&ruid, &euid, &suid);
+ fprintf(outfile, "user id = "F_uid"\n", ruid);
+ fprintf(outfile, "effective user id = "F_uid"\n", euid);
+ fprintf(outfile, "saved set-user id = "F_uid"\n", suid);
+ }
+#else /* !HAVE_GETRESUID */
fprintf(outfile, "user id = "F_uid"\n", Getuid());
fprintf(outfile, "effective user id = "F_uid"\n", Geteuid());
+#endif /* !HAVE_GETRESUID */
+#if HAVE_GETRESGID
+ {
+ gid_t rgid, egid, sgid;
+ getresgid(&rgid, &egid, &sgid);
+ fprintf(outfile, "group id = "F_gid"\n", rgid);
+ fprintf(outfile, "effective group id = "F_gid"\n", egid);
+ fprintf(outfile, "saved set-group id = "F_gid"\n", sgid);
+ }
+#else /* !HAVE_GETRESGID */
fprintf(outfile, "group id = "F_gid"\n", Getgid());
fprintf(outfile, "effective group id = "F_gid"\n", Getegid());
+#endif /* !HAVE_GETRESGID */
/* Simple process features */
fprintf(outfile, "\n");