From: Thorsten Kukuk <kukuk@suse.com>
Date: Wed, 31 May 2023 06:55:33 +0000 (+0200)
Subject: wall: query logind for list of users with tty (#2088)
X-Git-Tag: v2.40-rc1~274^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=87fcd95ac5ad18e471b17f448daa55b2ce2fac6a;p=thirdparty%2Futil-linux.git

wall: query logind for list of users with tty (#2088)
---

diff --git a/configure.ac b/configure.ac
index d631b062d2..17d3ab703b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2491,6 +2491,7 @@ AS_IF([test "x$with_systemd" != xno], [
     [*:yes],
        AC_DEFINE([HAVE_LIBSYSTEMD], [1], [Define if libsystemd is available])
        AC_DEFINE([USE_SYSTEMD], [1], [Define if systemd support is wanted ])
+       AC_CHECK_DECLS([sd_session_get_username], [], [], [#include <systemd/sd-login.h>])
   )
 ])
 AM_CONDITIONAL([HAVE_SYSTEMD], [test "x$have_systemd" = xyes])
diff --git a/meson.build b/meson.build
index f0ebe07414..66d90e15ae 100644
--- a/meson.build
+++ b/meson.build
@@ -311,6 +311,11 @@ lib_systemd = dependency(
   required : get_option('systemd'))
 conf.set('HAVE_LIBSYSTEMD', lib_systemd.found() ? 1 : false)
 
+have = cc.has_function(
+  'sd_session_get_username',
+  dependencies : lib_systemd)
+conf.set('HAVE_DECL_SD_SESSION_GET_USERNAME', have ? 1 : false)
+
 lib_udev = dependency(
   'libudev',
   required : get_option('systemd'))
@@ -2316,7 +2321,7 @@ exe = executable(
   agetty_sources,
   include_directories : includes,
   link_with : [lib_common, logindefs_c],
-  dependencies : BSD ? lib_util : [],
+  dependencies : [BSD ? lib_util : [], lib_systemd],
   install_dir : sbindir,
   install : opt,
   build_by_default : opt)
@@ -2362,6 +2367,7 @@ exe = executable(
   wall_sources,
   include_directories : includes,
   link_with : [lib_common],
+  dependencies : [lib_systemd],
   install_dir : usrbin_exec_dir,
   install : opt,
   build_by_default : opt)
@@ -2380,6 +2386,7 @@ exe = executable(
   write_sources,
   include_directories : includes,
   link_with : [lib_common],
+  dependencies : [lib_systemd],
   install_dir : usrbin_exec_dir,
   install : opt,
   build_by_default : opt)
diff --git a/term-utils/Makemodule.am b/term-utils/Makemodule.am
index 07004d43ca..1542320422 100644
--- a/term-utils/Makemodule.am
+++ b/term-utils/Makemodule.am
@@ -98,6 +98,10 @@ dist_noinst_DATA += term-utils/wall.1.adoc
 wall_CFLAGS = $(SUID_CFLAGS) $(AM_CFLAGS)
 wall_LDFLAGS = $(SUID_LDFLAGS) $(AM_LDFLAGS)
 wall_LDADD = $(LDADD) libcommon.la
+if HAVE_SYSTEMD
+wall_LDADD += $(SYSTEMD_LIBS)
+wall_CFLAGS += $(SYSTEMD_CFLAGS)
+endif
 if USE_TTY_GROUP
 if MAKEINSTALL_DO_CHOWN
 install-exec-hook-wall::
diff --git a/term-utils/wall.c b/term-utils/wall.c
index c601d3e5b7..313b1bdee5 100644
--- a/term-utils/wall.c
+++ b/term-utils/wall.c
@@ -61,6 +61,11 @@
 #include <sys/types.h>
 #include <grp.h>
 
+#if defined(USE_SYSTEMD) && HAVE_DECL_SD_SESSION_GET_USERNAME == 1
+# include <systemd/sd-login.h>
+# include <systemd/sd-daemon.h>
+#endif
+
 #include "nls.h"
 #include "xalloc.h"
 #include "strutils.h"
@@ -246,6 +251,37 @@ int main(int argc, char **argv)
 
 	iov.iov_base = mbuf;
 	iov.iov_len = mbufsize;
+#if defined(USE_SYSTEMD) && HAVE_DECL_SD_SESSION_GET_USERNAME == 1
+	if (sd_booted() > 0) {
+		char **sessions_list;
+		int sessions;
+
+		sessions = sd_get_sessions(&sessions_list);
+		if (sessions < 0)
+			errx(EXIT_FAILURE, _("error getting sessions: %s"),
+	             		strerror(-sessions));
+
+		for (int i = 0; i < sessions; i++) {
+			char *name, *tty;
+			int r;
+
+			if ((r = sd_session_get_username(sessions_list[i], &name)) < 0)
+				errx(EXIT_FAILURE, _("get user name failed: %s"), strerror (-r));
+
+			if (!(group_buf && !is_gr_member(name, group_buf))) {
+				if (sd_session_get_tty(sessions_list[i], &tty) >= 0) {
+					if ((p = ttymsg(&iov, 1, tty, timeout)) != NULL)
+						warnx("%s", p);
+
+					free(tty);
+				}
+			}
+			free(name);
+			free(sessions_list[i]);
+		}
+		free(sessions_list);
+	} else {
+#endif
 	while((utmpptr = getutxent())) {
 		if (!utmpptr->ut_user[0])
 			continue;
@@ -269,6 +305,9 @@ int main(int argc, char **argv)
 			warnx("%s", p);
 	}
 	endutxent();
+#if defined(USE_SYSTEMD) && HAVE_DECL_SD_SESSION_GET_USERNAME == 1
+	}
+#endif
 	free(mbuf);
 	free_group_workspace(group_buf);
 	exit(EXIT_SUCCESS);