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patch was slightly modified to be applied to openssh-7.2_p2
Original patch:
http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/ssh-agent.c.diff?r1=1.214&r2=1.215&sortby=date&f=h&f=u
===================================================================
RCS file: /cvs/src/usr.bin/ssh/ssh-agent.c,v
retrieving revision 1.214
retrieving revision 1.215
diff -u -r1.214 -r1.215
--- a/ssh-agent.c
+++ b/ssh-agent.c
@@ -69,11 +69,16 @@
#include "misc.h"
#include "digest.h"
#include "ssherr.h"
+#include "match.h"
#ifdef ENABLE_PKCS11
#include "ssh-pkcs11.h"
#endif
+#ifndef DEFAULT_PKCS11_WHITELIST
+# define DEFAULT_PKCS11_WHITELIST "/usr/lib/*,/usr/local/lib/*"
+#endif
+
#if defined(HAVE_SYS_PRCTL_H)
#include <sys/prctl.h> /* For prctl() and PR_SET_DUMPABLE */
#endif
@@ -121,6 +126,9 @@
char socket_name[PATH_MAX];
char socket_dir[PATH_MAX];
+/* PKCS#11 path whitelist */
+static char *pkcs11_whitelist;
+
/* locking */
#define LOCK_SIZE 32
#define LOCK_SALT_SIZE 16
@@ -724,7 +732,7 @@
static void
process_add_smartcard_key(SocketEntry *e)
{
- char *provider = NULL, *pin;
+ char *provider = NULL, *pin, canonical_provider[PATH_MAX];
int r, i, version, count = 0, success = 0, confirm = 0;
u_int seconds;
time_t death = 0;
@@ -756,10 +764,21 @@
goto send;
}
}
+ if (realpath(provider, canonical_provider) == NULL) {
+ verbose("failed PKCS#11 add of \"%.100s\": realpath: %s",
+ provider, strerror(errno));
+ goto send;
+ }
+ if (match_pattern_list(canonical_provider, pkcs11_whitelist, 0) != 1) {
+ verbose("refusing PKCS#11 add of \"%.100s\": "
+ "provider not whitelisted", canonical_provider);
+ goto send;
+ }
+ debug("%s: add %.100s", __func__, canonical_provider);
if (lifetime && !death)
death = monotime() + lifetime;
- count = pkcs11_add_provider(provider, pin, &keys);
+ count = pkcs11_add_provider(canonical_provider, pin, &keys);
for (i = 0; i < count; i++) {
k = keys[i];
version = k->type == KEY_RSA1 ? 1 : 2;
@@ -767,8 +786,8 @@
if (lookup_identity(k, version) == NULL) {
id = xcalloc(1, sizeof(Identity));
id->key = k;
- id->provider = xstrdup(provider);
- id->comment = xstrdup(provider); /* XXX */
+ id->provider = xstrdup(canonical_provider);
+ id->comment = xstrdup(canonical_provider); /* XXX */
id->death = death;
id->confirm = confirm;
TAILQ_INSERT_TAIL(&tab->idlist, id, next);
@@ -1157,7 +1176,7 @@
{
fprintf(stderr,
"usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n"
- " [-t life] [command [arg ...]]\n"
+ " [-P pkcs11_whitelist] [-t life] [command [arg ...]]\n"
" ssh-agent [-c | -s] -k\n");
exit(1);
}
@@ -1191,7 +1210,7 @@
OpenSSL_add_all_algorithms();
#endif
- while ((ch = getopt(ac, av, "cDdksE:a:t:")) != -1) {
+ while ((ch = getopt(ac, av, "cDdksE:a:P:t:")) != -1) {
switch (ch) {
case 'E':
fingerprint_hash = ssh_digest_alg_by_name(optarg);
@@ -1206,6 +1225,11 @@
case 'k':
k_flag++;
break;
+ case 'P':
+ if (pkcs11_whitelist != NULL)
+ fatal("-P option already specified");
+ pkcs11_whitelist = xstrdup(optarg);
+ break;
case 's':
if (c_flag)
usage();
@@ -1240,6 +1264,9 @@
if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag))
usage();
+ if (pkcs11_whitelist == NULL)
+ pkcs11_whitelist = xstrdup(DEFAULT_PKCS11_WHITELIST);
+
if (ac == 0 && !c_flag && !s_flag) {
shell = getenv("SHELL");
if (shell != NULL && (len = strlen(shell)) > 2 &&
@@ -1385,7 +1412,7 @@
signal(SIGTERM, cleanup_handler);
nalloc = 0;
- if (pledge("stdio cpath unix id proc exec", NULL) == -1)
+ if (pledge("stdio rpath cpath unix id proc exec", NULL) == -1)
fatal("%s: pledge: %s", __progname, strerror(errno));
while (1) {
|
