diff options
Diffstat (limited to 'ssh-agent.c')
| -rw-r--r-- | ssh-agent.c | 80 |
1 files changed, 58 insertions, 22 deletions
diff --git a/ssh-agent.c b/ssh-agent.c index aeda656ac804..34b19b754ec1 100644 --- a/ssh-agent.c +++ b/ssh-agent.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh-agent.c,v 1.199 2015/03/04 21:12:59 djm Exp $ */ +/* $OpenBSD: ssh-agent.c,v 1.203 2015/05/15 05:44:21 dtucker Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland @@ -68,6 +68,9 @@ #include <time.h> #include <string.h> #include <unistd.h> +#ifdef HAVE_UTIL_H +# include <util.h> +#endif #include "key.h" /* XXX for typedef */ #include "buffer.h" /* XXX for typedef */ @@ -140,8 +143,12 @@ char socket_name[PATH_MAX]; char socket_dir[PATH_MAX]; /* locking */ +#define LOCK_SIZE 32 +#define LOCK_SALT_SIZE 16 +#define LOCK_ROUNDS 1 int locked = 0; -char *lock_passwd = NULL; +char lock_passwd[LOCK_SIZE]; +char lock_salt[LOCK_SALT_SIZE]; extern char *__progname; @@ -660,23 +667,45 @@ send: static void process_lock_agent(SocketEntry *e, int lock) { - int r, success = 0; - char *passwd; + int r, success = 0, delay; + char *passwd, passwdhash[LOCK_SIZE]; + static u_int fail_count = 0; + size_t pwlen; - if ((r = sshbuf_get_cstring(e->request, &passwd, NULL)) != 0) + if ((r = sshbuf_get_cstring(e->request, &passwd, &pwlen)) != 0) fatal("%s: buffer error: %s", __func__, ssh_err(r)); - if (locked && !lock && strcmp(passwd, lock_passwd) == 0) { - locked = 0; - explicit_bzero(lock_passwd, strlen(lock_passwd)); - free(lock_passwd); - lock_passwd = NULL; - success = 1; + if (pwlen == 0) { + debug("empty password not supported"); + } else if (locked && !lock) { + if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt), + passwdhash, sizeof(passwdhash), LOCK_ROUNDS) < 0) + fatal("bcrypt_pbkdf"); + if (timingsafe_bcmp(passwdhash, lock_passwd, LOCK_SIZE) == 0) { + debug("agent unlocked"); + locked = 0; + fail_count = 0; + explicit_bzero(lock_passwd, sizeof(lock_passwd)); + success = 1; + } else { + /* delay in 0.1s increments up to 10s */ + if (fail_count < 100) + fail_count++; + delay = 100000 * fail_count; + debug("unlock failed, delaying %0.1lf seconds", + (double)delay/1000000); + usleep(delay); + } + explicit_bzero(passwdhash, sizeof(passwdhash)); } else if (!locked && lock) { + debug("agent locked"); locked = 1; - lock_passwd = xstrdup(passwd); + arc4random_buf(lock_salt, sizeof(lock_salt)); + if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt), + lock_passwd, sizeof(lock_passwd), LOCK_ROUNDS) < 0) + fatal("bcrypt_pbkdf"); success = 1; } - explicit_bzero(passwd, strlen(passwd)); + explicit_bzero(passwd, pwlen); free(passwd); send_status(e, success); } @@ -929,7 +958,7 @@ new_socket(sock_type type, int fd) } old_alloc = sockets_alloc; new_alloc = sockets_alloc + 10; - sockets = xrealloc(sockets, new_alloc, sizeof(sockets[0])); + sockets = xreallocarray(sockets, new_alloc, sizeof(sockets[0])); for (i = old_alloc; i < new_alloc; i++) sockets[i].type = AUTH_UNUSED; sockets_alloc = new_alloc; @@ -1137,7 +1166,7 @@ static void usage(void) { fprintf(stderr, - "usage: ssh-agent [-c | -s] [-d] [-a bind_address] [-E fingerprint_hash]\n" + "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n" " [-t life] [command [arg ...]]\n" " ssh-agent [-c | -s] -k\n"); exit(1); @@ -1146,7 +1175,7 @@ usage(void) int main(int ac, char **av) { - int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0; + int c_flag = 0, d_flag = 0, D_flag = 0, k_flag = 0, s_flag = 0; int sock, fd, ch, result, saved_errno; u_int nalloc; char *shell, *format, *pidstr, *agentsocket = NULL; @@ -1181,7 +1210,7 @@ main(int ac, char **av) __progname = ssh_get_progname(av[0]); seed_rng(); - while ((ch = getopt(ac, av, "cdksE:a:t:")) != -1) { + while ((ch = getopt(ac, av, "cDdksE:a:t:")) != -1) { switch (ch) { case 'E': fingerprint_hash = ssh_digest_alg_by_name(optarg); @@ -1202,10 +1231,15 @@ main(int ac, char **av) s_flag++; break; case 'd': - if (d_flag) + if (d_flag || D_flag) usage(); d_flag++; break; + case 'D': + if (d_flag || D_flag) + usage(); + D_flag++; + break; case 'a': agentsocket = optarg; break; @@ -1222,7 +1256,7 @@ main(int ac, char **av) ac -= optind; av += optind; - if (ac > 0 && (c_flag || k_flag || s_flag || d_flag)) + if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag)) usage(); if (ac == 0 && !c_flag && !s_flag) { @@ -1291,8 +1325,10 @@ main(int ac, char **av) * Fork, and have the parent execute the command, if any, or present * the socket data. The child continues as the authentication agent. */ - if (d_flag) { - log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1); + if (D_flag || d_flag) { + log_init(__progname, + d_flag ? SYSLOG_LEVEL_DEBUG3 : SYSLOG_LEVEL_INFO, + SYSLOG_FACILITY_AUTH, 1); format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, SSH_AUTHSOCKET_ENV_NAME); @@ -1364,7 +1400,7 @@ skip: parent_alive_interval = 10; idtab_init(); signal(SIGPIPE, SIG_IGN); - signal(SIGINT, d_flag ? cleanup_handler : SIG_IGN); + signal(SIGINT, (d_flag | D_flag) ? cleanup_handler : SIG_IGN); signal(SIGHUP, cleanup_handler); signal(SIGTERM, cleanup_handler); nalloc = 0; |