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Diffstat (limited to 'usr/src/cmd/ssh/ssh-agent/ssh-agent.c')
-rw-r--r--usr/src/cmd/ssh/ssh-agent/ssh-agent.c254
1 files changed, 166 insertions, 88 deletions
diff --git a/usr/src/cmd/ssh/ssh-agent/ssh-agent.c b/usr/src/cmd/ssh/ssh-agent/ssh-agent.c
index 2fd2086561..3d2ea9732c 100644
--- a/usr/src/cmd/ssh/ssh-agent/ssh-agent.c
+++ b/usr/src/cmd/ssh/ssh-agent/ssh-agent.c
@@ -40,7 +40,7 @@
#include "includes.h"
#include "sys-queue.h"
-RCSID("$OpenBSD: ssh-agent.c,v 1.105 2002/10/01 20:34:12 markus Exp $");
+RCSID("$OpenBSD: ssh-agent.c,v 1.159 2008/06/28 14:05:15 djm Exp $");
#ifdef HAVE_SOLARIS_PRIVILEGE
#include <priv.h>
@@ -54,11 +54,12 @@ RCSID("$OpenBSD: ssh-agent.c,v 1.105 2002/10/01 20:34:12 markus Exp $");
#include "buffer.h"
#include "bufaux.h"
#include "xmalloc.h"
-#include "getput.h"
#include "key.h"
#include "authfd.h"
#include "compat.h"
#include "log.h"
+#include "readpass.h"
+#include "misc.h"
typedef enum {
AUTH_UNUSED,
@@ -82,6 +83,7 @@ typedef struct identity {
Key *key;
char *comment;
u_int death;
+ u_int confirm;
} Identity;
typedef struct {
@@ -96,10 +98,11 @@ int max_fd = 0;
/* pid of shell == parent of agent */
pid_t parent_pid = -1;
+u_int parent_alive_interval = 0;
/* pathname and directory for AUTH_SOCKET */
-char socket_name[1024];
-char socket_dir[1024];
+char socket_name[MAXPATHLEN];
+char socket_dir[MAXPATHLEN];
/* locking */
int locked = 0;
@@ -111,6 +114,9 @@ extern char *__progname;
char *__progname;
#endif
+/* Default lifetime (0 == forever) */
+static int lifetime = 0;
+
static void
close_socket(SocketEntry *e)
{
@@ -164,6 +170,23 @@ lookup_identity(Key *key, int version)
return (NULL);
}
+/* Check confirmation of keysign request */
+static int
+confirm_key(Identity *id)
+{
+ char *p;
+ int ret = -1;
+
+ p = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX);
+ if (ask_permission(
+ gettext("Allow use of key %s?\nKey fingerprint %s."),
+ id->comment, p))
+ ret = 0;
+ xfree(p);
+
+ return (ret);
+}
+
/* send list of supported public keys to 'client' */
static void
process_request_identities(SocketEntry *e, int version)
@@ -227,7 +250,7 @@ process_authentication_challenge1(SocketEntry *e)
goto failure;
id = lookup_identity(key, 1);
- if (id != NULL) {
+ if (id != NULL && (!id->confirm || confirm_key(id) == 0)) {
Key *private = id->key;
/* Decrypt the challenge using the private key. */
if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0)
@@ -270,6 +293,8 @@ process_sign_request2(SocketEntry *e)
{
u_char *blob, *data, *signature = NULL;
u_int blen, dlen, slen = 0;
+ extern uint32_t datafellows;
+ int odatafellows;
int ok = -1, flags;
Buffer msg;
Key *key;
@@ -280,16 +305,17 @@ process_sign_request2(SocketEntry *e)
data = buffer_get_string(&e->request, &dlen);
flags = buffer_get_int(&e->request);
+ odatafellows = datafellows;
if (flags & SSH_AGENT_OLD_SIGNATURE)
datafellows = SSH_BUG_SIGBLOB;
key = key_from_blob(blob, blen);
if (key != NULL) {
Identity *id = lookup_identity(key, 2);
- if (id != NULL)
+ if (id != NULL && (!id->confirm || confirm_key(id) == 0))
ok = key_sign(id->key, &signature, &slen, data, dlen);
+ key_free(key);
}
- key_free(key);
buffer_init(&msg);
if (ok == 0) {
buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
@@ -305,6 +331,7 @@ process_sign_request2(SocketEntry *e)
xfree(blob);
if (signature != NULL)
xfree(signature);
+ datafellows = odatafellows;
}
/* shared */
@@ -338,7 +365,7 @@ process_remove_identity(SocketEntry *e, int version)
if (id != NULL) {
/*
* We have this key. Free the old key. Since we
- * don\'t want to leave empty slots in the middle of
+ * don't want to leave empty slots in the middle of
* the array, we actually free the key there and move
* all the entries between the empty slot and the end
* of the array.
@@ -381,10 +408,11 @@ process_remove_all_identities(SocketEntry *e, int version)
buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
}
-static void
+/* removes expired keys and returns number of seconds until the next expiry */
+static u_int
reaper(void)
{
- u_int now = time(NULL);
+ u_int deadline = 0, now = time(NULL);
Identity *id, *nxt;
int version;
Idtab *tab;
@@ -393,20 +421,30 @@ reaper(void)
tab = idtab_lookup(version);
for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
nxt = TAILQ_NEXT(id, next);
- if (id->death != 0 && now >= id->death) {
+ if (id->death == 0)
+ continue;
+ if (now >= id->death) {
+ debug("expiring key '%s'", id->comment);
TAILQ_REMOVE(&tab->idlist, id, next);
free_identity(id);
tab->nentries--;
- }
+ } else
+ deadline = (deadline == 0) ? id->death :
+ MIN(deadline, id->death);
}
}
+ if (deadline == 0 || deadline <= now)
+ return 0;
+ else
+ return (deadline - now);
}
static void
process_add_identity(SocketEntry *e, int version)
{
Idtab *tab = idtab_lookup(version);
- int type, success = 0, death = 0;
+ Identity *id;
+ int type, success = 0, death = 0, confirm = 0;
char *type_name, *comment;
Key *k = NULL;
@@ -457,33 +495,54 @@ process_add_identity(SocketEntry *e, int version)
}
break;
}
+ /* enable blinding */
+ switch (k->type) {
+ case KEY_RSA:
+ case KEY_RSA1:
+ if (RSA_blinding_on(k->rsa, NULL) != 1) {
+ error("process_add_identity: RSA_blinding_on failed");
+ key_free(k);
+ goto send;
+ }
+ break;
+ }
comment = buffer_get_string(&e->request, NULL);
if (k == NULL) {
xfree(comment);
goto send;
}
- success = 1;
while (buffer_len(&e->request)) {
- switch (buffer_get_char(&e->request)) {
+ switch ((type = buffer_get_char(&e->request))) {
case SSH_AGENT_CONSTRAIN_LIFETIME:
death = time(NULL) + buffer_get_int(&e->request);
break;
- default:
+ case SSH_AGENT_CONSTRAIN_CONFIRM:
+ confirm = 1;
break;
+ default:
+ error("process_add_identity: "
+ "Unknown constraint type %d", type);
+ xfree(comment);
+ key_free(k);
+ goto send;
}
}
- if (lookup_identity(k, version) == NULL) {
- Identity *id = xmalloc(sizeof(Identity));
+ success = 1;
+ if (lifetime && !death)
+ death = time(NULL) + lifetime;
+ if ((id = lookup_identity(k, version)) == NULL) {
+ id = xmalloc(sizeof(Identity));
id->key = k;
- id->comment = comment;
- id->death = death;
TAILQ_INSERT_TAIL(&tab->idlist, id, next);
/* Increment the number of identities. */
tab->nentries++;
} else {
key_free(k);
- xfree(comment);
+ xfree(id->comment);
}
+ id->comment = comment;
+ id->death = death;
+ id->confirm = confirm;
send:
buffer_put_int(&e->output, 1);
buffer_put_char(&e->output,
@@ -540,13 +599,10 @@ process_message(SocketEntry *e)
u_int msg_len, type;
u_char *cp;
- /* kill dead keys */
- reaper();
-
if (buffer_len(&e->input) < 5)
return; /* Incomplete message. */
cp = buffer_ptr(&e->input);
- msg_len = GET_32BIT(cp);
+ msg_len = get_u32(cp);
if (msg_len > 256 * 1024) {
close_socket(e);
return;
@@ -631,10 +687,9 @@ process_message(SocketEntry *e)
static void
new_socket(sock_type type, int fd)
{
- u_int i, old_alloc;
+ u_int i, old_alloc, new_alloc;
- if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
- error("fcntl O_NONBLOCK: %s", strerror(errno));
+ set_nonblock(fd);
if (fd > max_fd)
max_fd = fd;
@@ -642,32 +697,32 @@ new_socket(sock_type type, int fd)
for (i = 0; i < sockets_alloc; i++)
if (sockets[i].type == AUTH_UNUSED) {
sockets[i].fd = fd;
- sockets[i].type = type;
buffer_init(&sockets[i].input);
buffer_init(&sockets[i].output);
buffer_init(&sockets[i].request);
+ sockets[i].type = type;
return;
}
old_alloc = sockets_alloc;
- sockets_alloc += 10;
- if (sockets)
- sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
- else
- sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
- for (i = old_alloc; i < sockets_alloc; i++)
+ new_alloc = sockets_alloc + 10;
+ sockets = xrealloc(sockets, new_alloc * sizeof(sockets[0]));
+ for (i = old_alloc; i < new_alloc; i++)
sockets[i].type = AUTH_UNUSED;
- sockets[old_alloc].type = type;
+ sockets_alloc = new_alloc;
sockets[old_alloc].fd = fd;
buffer_init(&sockets[old_alloc].input);
buffer_init(&sockets[old_alloc].output);
buffer_init(&sockets[old_alloc].request);
+ sockets[old_alloc].type = type;
}
static int
-prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
+prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp,
+ struct timeval **tvpp)
{
- u_int i, sz;
+ u_int i, sz, deadline;
int n = 0;
+ static struct timeval tv;
for (i = 0; i < sockets_alloc; i++) {
switch (sockets[i].type) {
@@ -711,6 +766,17 @@ prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
break;
}
}
+ deadline = reaper();
+ if (parent_alive_interval != 0)
+ deadline = (deadline == 0) ? parent_alive_interval :
+ MIN(deadline, parent_alive_interval);
+ if (deadline == 0) {
+ *tvpp = NULL;
+ } else {
+ tv.tv_sec = deadline;
+ tv.tv_usec = 0;
+ *tvpp = &tv;
+ }
return (1);
}
@@ -733,7 +799,7 @@ after_select(fd_set *readset, fd_set *writeset)
if (FD_ISSET(sockets[i].fd, readset)) {
slen = sizeof(sunaddr);
sock = accept(sockets[i].fd,
- (struct sockaddr *) &sunaddr, &slen);
+ (struct sockaddr *)&sunaddr, &slen);
if (sock < 0) {
error("accept from AUTH_SOCKET: %s",
strerror(errno));
@@ -763,7 +829,8 @@ after_select(fd_set *readset, fd_set *writeset)
buffer_ptr(&sockets[i].output),
buffer_len(&sockets[i].output));
if (len == -1 && (errno == EAGAIN ||
- errno == EINTR))
+ errno == EINTR ||
+ errno == EWOULDBLOCK))
continue;
break;
} while (1);
@@ -777,7 +844,8 @@ after_select(fd_set *readset, fd_set *writeset)
do {
len = read(sockets[i].fd, buf, sizeof(buf));
if (len == -1 && (errno == EAGAIN ||
- errno == EINTR))
+ errno == EINTR ||
+ errno == EWOULDBLOCK))
continue;
break;
} while (1);
@@ -795,7 +863,7 @@ after_select(fd_set *readset, fd_set *writeset)
}
static void
-cleanup_socket(void *p)
+cleanup_socket(void)
{
if (socket_name[0])
unlink(socket_name);
@@ -803,32 +871,29 @@ cleanup_socket(void *p)
rmdir(socket_dir);
}
-static void
+void
cleanup_exit(int i)
{
- cleanup_socket(NULL);
- exit(i);
+ cleanup_socket();
+ _exit(i);
}
+/*ARGSUSED*/
static void
cleanup_handler(int sig)
{
- cleanup_socket(NULL);
+ cleanup_socket();
_exit(2);
}
static void
-check_parent_exists(int sig)
+check_parent_exists(void)
{
- int save_errno = errno;
-
- if (parent_pid != -1 && getppid() != parent_pid) {
+ if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
/* printf("Parent has died - Authentication agent exiting.\n"); */
- cleanup_handler(sig); /* safe */
+ cleanup_socket();
+ _exit(2);
}
- signal(SIGALRM, check_parent_exists);
- alarm(10);
- errno = save_errno;
}
static void
@@ -841,7 +906,8 @@ usage(void)
" -s Generate Bourne shell commands on stdout.\n"
" -k Kill the current agent.\n"
" -d Debug mode.\n"
- " -a socket Bind agent socket to given name.\n"),
+ " -a socket Bind agent socket to given name.\n"
+ " -t life Default identity lifetime (seconds).\n"),
__progname);
exit(1);
}
@@ -849,7 +915,9 @@ usage(void)
int
main(int ac, char **av)
{
- int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc;
+ int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0;
+ int sock, fd, ch, result, saved_errno;
+ u_int nalloc;
char *shell, *pidstr, *agentsocket = NULL;
const char *format;
fd_set *readsetp = NULL, *writesetp = NULL;
@@ -857,30 +925,30 @@ main(int ac, char **av)
#ifdef HAVE_SETRLIMIT
struct rlimit rlim;
#endif
-#ifdef HAVE_CYGWIN
int prev_mask;
-#endif
extern int optind;
extern char *optarg;
pid_t pid;
char pidstrbuf[1 + 3 * sizeof pid];
+ struct timeval *tvp = NULL;
#ifdef HAVE_SOLARIS_PRIVILEGE
priv_set_t *myprivs;
#endif /* HAVE_SOLARIS_PRIVILEGE */
+ /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
+ sanitise_stdfd();
+
/* drop */
setegid(getgid());
setgid(getgid());
- (void) g11n_setlocale(LC_ALL, "");
-
SSLeay_add_all_algorithms();
__progname = get_progname(av[0]);
init_rng();
seed_rng();
- while ((ch = getopt(ac, av, "cdksa:")) != -1) {
+ while ((ch = getopt(ac, av, "cdksa:t:")) != -1) {
switch (ch) {
case 'c':
if (s_flag)
@@ -903,6 +971,12 @@ main(int ac, char **av)
case 'a':
agentsocket = optarg;
break;
+ case 't':
+ if ((lifetime = convtime(optarg)) == -1) {
+ fprintf(stderr, gettext("Invalid lifetime\n"));
+ usage();
+ }
+ break;
default:
usage();
}
@@ -915,7 +989,8 @@ main(int ac, char **av)
if (ac == 0 && !c_flag && !s_flag) {
shell = getenv("SHELL");
- if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
+ if (shell != NULL &&
+ strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
c_flag = 1;
}
if (k_flag) {
@@ -929,8 +1004,8 @@ main(int ac, char **av)
pid = atoi(pidstr);
if (pid < 1) {
fprintf(stderr,
- gettext("%s=\")%s\", which is not a good PID\n"),
- SSH_AGENTPID_ENV_NAME, pidstr);
+ gettext("%s not set, cannot kill agent\n"),
+ SSH_AGENTPID_ENV_NAME);
exit(1);
}
if (kill(pid, SIGTERM) == -1) {
@@ -948,7 +1023,7 @@ main(int ac, char **av)
if (agentsocket == NULL) {
/* Create private directory for agent socket */
- strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
+ strlcpy(socket_dir, "/tmp/ssh-XXXXXXXXXX", sizeof socket_dir);
if (mkdtemp(socket_dir) == NULL) {
perror("mkdtemp: private socket dir");
exit(1);
@@ -968,25 +1043,21 @@ main(int ac, char **av)
sock = socket(AF_UNIX, SOCK_STREAM, 0);
if (sock < 0) {
perror("socket");
+ *socket_name = '\0'; /* Don't unlink any existing file */
cleanup_exit(1);
}
memset(&sunaddr, 0, sizeof(sunaddr));
sunaddr.sun_family = AF_UNIX;
strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
-#ifdef HAVE_CYGWIN
prev_mask = umask(0177);
-#endif
- if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
+ if (bind(sock, (struct sockaddr *) &sunaddr, sizeof(sunaddr)) < 0) {
perror("bind");
-#ifdef HAVE_CYGWIN
+ *socket_name = '\0'; /* Don't unlink any existing file */
umask(prev_mask);
-#endif
cleanup_exit(1);
}
-#ifdef HAVE_CYGWIN
umask(prev_mask);
-#endif
- if (listen(sock, 128) < 0) {
+ if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
perror("listen");
cleanup_exit(1);
}
@@ -1019,7 +1090,7 @@ main(int ac, char **av)
printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
SSH_AGENTPID_ENV_NAME);
printf("echo ");
- printf(gettext("Agent pid %ld;\n"), (long)pid);
+ printf(gettext("Agent pid %ld;\n"), (long)pid);
exit(0);
}
if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
@@ -1062,9 +1133,14 @@ main(int ac, char **av)
}
(void)chdir("/");
- close(0);
- close(1);
- close(2);
+ if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
+ /* XXX might close listen socket */
+ (void)dup2(fd, STDIN_FILENO);
+ (void)dup2(fd, STDOUT_FILENO);
+ (void)dup2(fd, STDERR_FILENO);
+ if (fd > 2)
+ close(fd);
+ }
#ifdef HAVE_SETRLIMIT
/* deny core dumps, since memory contains unencrypted private keys */
@@ -1076,12 +1152,9 @@ main(int ac, char **av)
#endif
skip:
- fatal_add_cleanup(cleanup_socket, NULL);
new_socket(AUTH_SOCKET, sock);
- if (ac > 0) {
- signal(SIGALRM, check_parent_exists);
- alarm(10);
- }
+ if (ac > 0)
+ parent_alive_interval = 10;
idtab_init();
if (!d_flag)
signal(SIGINT, SIG_IGN);
@@ -1091,13 +1164,18 @@ skip:
nalloc = 0;
while (1) {
- prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
- if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
- if (errno == EINTR)
+ prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp);
+ result = select(max_fd + 1, readsetp, writesetp, NULL, tvp);
+ saved_errno = errno;
+ if (parent_alive_interval != 0)
+ check_parent_exists();
+ (void) reaper(); /* remove expired keys */
+ if (result < 0) {
+ if (saved_errno == EINTR)
continue;
- fatal("select: %s", strerror(errno));
- }
- after_select(readsetp, writesetp);
+ fatal("select: %s", strerror(saved_errno));
+ } else if (result > 0)
+ after_select(readsetp, writesetp);
}
/* NOTREACHED */
return (0); /* keep lint happy */
generated by cgit v1.2.3 (git 2.39.1) at 2025-05-01 15:57:11 +0000