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--- UTC
r110506 | des | 2003-02-07 09:48:27 -0600 (Fri, 07 Feb 2003) | 4 lines
Set the ruid to the euid at startup as a workaround for a bug in pam_ssh.
r226103 | des | 2011-10-07 08:10:16 -0500 (Fri, 07 Oct 2011) | 5 lines
Add a -x option that causes ssh-agent(1) to exit when all clients have
disconnected.
--- ssh-agent.c.orig 2022-02-23 03:31:11.000000000 -0800
+++ ssh-agent.c 2022-03-02 12:50:47.745853000 -0800
@@ -189,11 +189,28 @@ static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
/* Refuse signing of non-SSH messages for web-origin FIDO keys */
static int restrict_websafe = 1;
+/*
+ * Client connection count; incremented in new_socket() and decremented in
+ * close_socket(). When it reaches 0, ssh-agent will exit. Since it is
+ * normally initialized to 1, it will never reach 0. However, if the -x
+ * option is specified, it is initialized to 0 in main(); in that case,
+ * ssh-agent will exit as soon as it has had at least one client but no
+ * longer has any.
+ */
+static int xcount = 1;
+
static void
close_socket(SocketEntry *e)
{
size_t i;
+ int last = 0;
+ if (e->type == AUTH_CONNECTION) {
+ debug("xcount %d -> %d", xcount, xcount - 1);
+ if (--xcount == 0)
+ last = 1;
+ }
+
close(e->fd);
sshbuf_free(e->input);
sshbuf_free(e->output);
@@ -206,6 +223,8 @@ close_socket(SocketEntry *e)
memset(e, '\0', sizeof(*e));
e->fd = -1;
e->type = AUTH_UNUSED;
+ if (last)
+ cleanup_exit(0);
}
static void
@@ -1707,6 +1726,10 @@ new_socket(sock_type type, int fd)
debug_f("type = %s", type == AUTH_CONNECTION ? "CONNECTION" :
(type == AUTH_SOCKET ? "SOCKET" : "UNKNOWN"));
+ if (type == AUTH_CONNECTION) {
+ debug("xcount %d -> %d", xcount, xcount + 1);
+ ++xcount;
+ }
set_nonblock(fd);
if (fd > max_fd)
@@ -1999,7 +2022,7 @@ static void
usage(void)
{
fprintf(stderr,
- "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n"
+ "usage: ssh-agent [-c | -s] [-Ddx] [-a bind_address] [-E fingerprint_hash]\n"
" [-P allowed_providers] [-t life]\n"
" ssh-agent [-a bind_address] [-E fingerprint_hash] [-P allowed_providers]\n"
" [-t life] command [arg ...]\n"
@@ -2033,6 +2056,7 @@ main(int ac, char **av)
/* drop */
setegid(getgid());
setgid(getgid());
+ setuid(geteuid());
platform_disable_tracing(0); /* strict=no */
@@ -2044,7 +2068,7 @@ main(int ac, char **av)
__progname = ssh_get_progname(av[0]);
seed_rng();
- while ((ch = getopt(ac, av, "cDdksE:a:O:P:t:")) != -1) {
+ while ((ch = getopt(ac, av, "cDdksE:a:O:P:t:x")) != -1) {
switch (ch) {
case 'E':
fingerprint_hash = ssh_digest_alg_by_name(optarg);
@@ -2093,6 +2117,9 @@ main(int ac, char **av)
fprintf(stderr, "Invalid lifetime\n");
usage();
}
+ break;
+ case 'x':
+ xcount = 0;
break;
default:
usage();
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