+/* $OpenBSD: ssh-agent.c,v 1.157 2007/09/25 23:48:57 canacar Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
*/
#include "includes.h"
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#ifdef HAVE_SYS_TIME_H
+# include <sys/time.h>
+#endif
+#ifdef HAVE_SYS_UN_H
+# include <sys/un.h>
+#endif
#include "openbsd-compat/sys-queue.h"
-RCSID("$OpenBSD: ssh-agent.c,v 1.111 2003/06/12 19:12:03 markus Exp $");
#include <openssl/evp.h>
#include <openssl/md5.h>
+#include "openbsd-compat/openssl-compat.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#ifdef HAVE_PATHS_H
+# include <paths.h>
+#endif
+#include <signal.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <string.h>
+#include <unistd.h>
+#include "xmalloc.h"
#include "ssh.h"
#include "rsa.h"
#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"
#ifdef SMARTCARD
#include "scard.h"
#endif
+#if defined(HAVE_SYS_PRCTL_H)
+#include <sys/prctl.h> /* For prctl() and PR_SET_DUMPABLE */
+#endif
+
typedef enum {
AUTH_UNUSED,
AUTH_SOCKET,
/* 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;
char *lock_passwd = NULL;
-#ifdef HAVE___PROGNAME
extern char *__progname;
-#else
-char *__progname;
-#endif
/* Default lifetime (0 == forever) */
static int lifetime = 0;
static int
confirm_key(Identity *id)
{
- char *p, prompt[1024];
+ char *p;
int ret = -1;
p = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX);
- snprintf(prompt, sizeof(prompt), "Allow use of key %s?\n"
- "Key fingerprint %s.", id->comment, p);
+ if (ask_permission("Allow use of key %s?\nKey fingerprint %s.",
+ id->comment, p))
+ ret = 0;
xfree(p);
- p = read_passphrase(prompt, RP_ALLOW_EOF);
- if (p != NULL) {
- /*
- * Accept empty responses and responses consisting
- * of the word "yes" as affirmative.
- */
- if (*p == '\0' || *p == '\n' || strcasecmp(p, "yes") == 0)
- ret = 0;
- xfree(p);
- }
+
return (ret);
}
Identity *id = lookup_identity(key, 2);
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);
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.
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;
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);
+ Identity *id;
int type, success = 0, death = 0, confirm = 0;
char *type_name, *comment;
Key *k = NULL;
}
if (lifetime && !death)
death = time(NULL) + lifetime;
- if (lookup_identity(k, version) == NULL) {
- Identity *id = xmalloc(sizeof(Identity));
+ if ((id = lookup_identity(k, version)) == NULL) {
+ id = xmalloc(sizeof(Identity));
id->key = k;
- id->comment = comment;
- id->death = death;
- id->confirm = confirm;
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,
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;
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;
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) {
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);
}
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));
}
static void
-cleanup_socket(void *p)
+cleanup_socket(void)
{
if (socket_name[0])
unlink(socket_name);
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 && kill(parent_pid, 0) < 0) {
/* printf("Parent has died - Authentication agent exiting.\n"); */
- cleanup_handler(sig); /* safe */
+ cleanup_socket();
+ _exit(2);
}
- mysignal(SIGALRM, check_parent_exists);
- alarm(10);
- errno = save_errno;
}
static void
usage(void)
{
- fprintf(stderr, "Usage: %s [options] [command [args ...]]\n",
+ fprintf(stderr, "usage: %s [options] [command [arg ...]]\n",
__progname);
fprintf(stderr, "Options:\n");
fprintf(stderr, " -c Generate C-shell commands on stdout.\n");
main(int ac, char **av)
{
int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0;
- int sock, fd, ch, nalloc;
+ int sock, fd, ch, result, saved_errno;
+ u_int nalloc;
char *shell, *format, *pidstr, *agentsocket = NULL;
fd_set *readsetp = NULL, *writesetp = NULL;
struct sockaddr_un sunaddr;
#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;
+
+ /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
+ sanitise_stdfd();
/* drop */
setegid(getgid());
setgid(getgid());
+#if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE)
+ /* Disable ptrace on Linux without sgid bit */
+ prctl(PR_SET_DUMPABLE, 0);
+#endif
+
SSLeay_add_all_algorithms();
__progname = ssh_get_progname(av[0]);
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) {
+ const char *errstr = NULL;
+
pidstr = getenv(SSH_AGENTPID_ENV_NAME);
if (pidstr == NULL) {
fprintf(stderr, "%s not set, cannot kill agent\n",
SSH_AGENTPID_ENV_NAME);
exit(1);
}
- pid = atoi(pidstr);
- if (pid < 1) {
- fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
- SSH_AGENTPID_ENV_NAME, pidstr);
+ pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
+ if (errstr) {
+ fprintf(stderr,
+ "%s=\"%s\", which is not a good PID: %s\n",
+ SSH_AGENTPID_ENV_NAME, pidstr, errstr);
exit(1);
}
if (kill(pid, SIGTERM) == -1) {
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);
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);
}
#endif
skip:
- fatal_add_cleanup(cleanup_socket, NULL);
new_socket(AUTH_SOCKET, sock);
- if (ac > 0) {
- mysignal(SIGALRM, check_parent_exists);
- alarm(10);
- }
+ if (ac > 0)
+ parent_alive_interval = 10;
idtab_init();
if (!d_flag)
signal(SIGINT, SIG_IGN);
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 */
}
andersk / gssapi-openssh.git / blobdiff