diff options
Diffstat (limited to 'crypto/openssh/ssh-agent.c')
| -rw-r--r-- | crypto/openssh/ssh-agent.c | 873 |
1 files changed, 873 insertions, 0 deletions
diff --git a/crypto/openssh/ssh-agent.c b/crypto/openssh/ssh-agent.c new file mode 100644 index 0000000..ae0f044 --- /dev/null +++ b/crypto/openssh/ssh-agent.c @@ -0,0 +1,873 @@ +/* $OpenBSD: ssh-agent.c,v 1.54 2001/04/03 13:56:11 stevesk Exp $ */ + +/* + * Author: Tatu Ylonen <ylo@cs.hut.fi> + * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland + * All rights reserved + * The authentication agent program. + * + * As far as I am concerned, the code I have written for this software + * can be used freely for any purpose. Any derived versions of this + * software must be clearly marked as such, and if the derived work is + * incompatible with the protocol description in the RFC file, it must be + * called by a name other than "ssh" or "Secure Shell". + * + * SSH2 implementation, + * Copyright (c) 2000 Markus Friedl. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "includes.h" +RCSID("$OpenBSD: ssh-agent.c,v 1.54 2001/04/03 13:56:11 stevesk Exp $"); +RCSID("$FreeBSD$"); + +#include <openssl/evp.h> +#include <openssl/md5.h> + +#include "ssh.h" +#include "rsa.h" +#include "buffer.h" +#include "bufaux.h" +#include "xmalloc.h" +#include "packet.h" +#include "getput.h" +#include "mpaux.h" +#include "key.h" +#include "authfd.h" +#include "cipher.h" +#include "kex.h" +#include "compat.h" +#include "log.h" + +typedef struct { + int fd; + enum { + AUTH_UNUSED, AUTH_SOCKET, AUTH_CONNECTION + } type; + Buffer input; + Buffer output; +} SocketEntry; + +u_int sockets_alloc = 0; +SocketEntry *sockets = NULL; + +typedef struct { + Key *key; + char *comment; +} Identity; + +typedef struct { + int nentries; + Identity *identities; +} Idtab; + +/* private key table, one per protocol version */ +Idtab idtable[3]; + +int max_fd = 0; + +/* pid of shell == parent of agent */ +pid_t parent_pid = -1; + +/* pathname and directory for AUTH_SOCKET */ +char socket_name[1024]; +char socket_dir[1024]; + +extern char *__progname; + +int prepare_select(fd_set **, fd_set **, int *); + +void +idtab_init(void) +{ + int i; + for (i = 0; i <=2; i++){ + idtable[i].identities = NULL; + idtable[i].nentries = 0; + } +} + +/* return private key table for requested protocol version */ +Idtab * +idtab_lookup(int version) +{ + if (version < 1 || version > 2) + fatal("internal error, bad protocol version %d", version); + return &idtable[version]; +} + +/* return matching private key for given public key */ +Key * +lookup_private_key(Key *key, int *idx, int version) +{ + int i; + Idtab *tab = idtab_lookup(version); + for (i = 0; i < tab->nentries; i++) { + if (key_equal(key, tab->identities[i].key)) { + if (idx != NULL) + *idx = i; + return tab->identities[i].key; + } + } + return NULL; +} + +/* send list of supported public keys to 'client' */ +void +process_request_identities(SocketEntry *e, int version) +{ + Idtab *tab = idtab_lookup(version); + Buffer msg; + int i; + + buffer_init(&msg); + buffer_put_char(&msg, (version == 1) ? + SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER); + buffer_put_int(&msg, tab->nentries); + for (i = 0; i < tab->nentries; i++) { + Identity *id = &tab->identities[i]; + if (id->key->type == KEY_RSA1) { + buffer_put_int(&msg, BN_num_bits(id->key->rsa->n)); + buffer_put_bignum(&msg, id->key->rsa->e); + buffer_put_bignum(&msg, id->key->rsa->n); + } else { + u_char *blob; + u_int blen; + key_to_blob(id->key, &blob, &blen); + buffer_put_string(&msg, blob, blen); + xfree(blob); + } + buffer_put_cstring(&msg, id->comment); + } + buffer_put_int(&e->output, buffer_len(&msg)); + buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); + buffer_free(&msg); +} + +/* ssh1 only */ +void +process_authentication_challenge1(SocketEntry *e) +{ + Key *key, *private; + BIGNUM *challenge; + int i, len; + Buffer msg; + MD5_CTX md; + u_char buf[32], mdbuf[16], session_id[16]; + u_int response_type; + + buffer_init(&msg); + key = key_new(KEY_RSA1); + challenge = BN_new(); + + buffer_get_int(&e->input); /* ignored */ + buffer_get_bignum(&e->input, key->rsa->e); + buffer_get_bignum(&e->input, key->rsa->n); + buffer_get_bignum(&e->input, challenge); + + /* Only protocol 1.1 is supported */ + if (buffer_len(&e->input) == 0) + goto failure; + buffer_get(&e->input, (char *) session_id, 16); + response_type = buffer_get_int(&e->input); + if (response_type != 1) + goto failure; + + private = lookup_private_key(key, NULL, 1); + if (private != NULL) { + /* Decrypt the challenge using the private key. */ + if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0) + goto failure; + + /* The response is MD5 of decrypted challenge plus session id. */ + len = BN_num_bytes(challenge); + if (len <= 0 || len > 32) { + log("process_authentication_challenge: bad challenge length %d", len); + goto failure; + } + memset(buf, 0, 32); + BN_bn2bin(challenge, buf + 32 - len); + MD5_Init(&md); + MD5_Update(&md, buf, 32); + MD5_Update(&md, session_id, 16); + MD5_Final(mdbuf, &md); + + /* Send the response. */ + buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE); + for (i = 0; i < 16; i++) + buffer_put_char(&msg, mdbuf[i]); + goto send; + } + +failure: + /* Unknown identity or protocol error. Send failure. */ + buffer_put_char(&msg, SSH_AGENT_FAILURE); +send: + buffer_put_int(&e->output, buffer_len(&msg)); + buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); + key_free(key); + BN_clear_free(challenge); + buffer_free(&msg); +} + +/* ssh2 only */ +void +process_sign_request2(SocketEntry *e) +{ + extern int datafellows; + Key *key, *private; + u_char *blob, *data, *signature = NULL; + u_int blen, dlen, slen = 0; + int flags; + Buffer msg; + int ok = -1; + + datafellows = 0; + + blob = buffer_get_string(&e->input, &blen); + data = buffer_get_string(&e->input, &dlen); + + flags = buffer_get_int(&e->input); + if (flags & SSH_AGENT_OLD_SIGNATURE) + datafellows = SSH_BUG_SIGBLOB; + + key = key_from_blob(blob, blen); + if (key != NULL) { + private = lookup_private_key(key, NULL, 2); + if (private != NULL) + ok = key_sign(private, &signature, &slen, data, dlen); + } + key_free(key); + buffer_init(&msg); + if (ok == 0) { + buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE); + buffer_put_string(&msg, signature, slen); + } else { + buffer_put_char(&msg, SSH_AGENT_FAILURE); + } + buffer_put_int(&e->output, buffer_len(&msg)); + buffer_append(&e->output, buffer_ptr(&msg), + buffer_len(&msg)); + buffer_free(&msg); + xfree(data); + xfree(blob); + if (signature != NULL) + xfree(signature); +} + +/* shared */ +void +process_remove_identity(SocketEntry *e, int version) +{ + Key *key = NULL, *private; + u_char *blob; + u_int blen; + u_int bits; + int success = 0; + + switch(version){ + case 1: + key = key_new(KEY_RSA1); + bits = buffer_get_int(&e->input); + buffer_get_bignum(&e->input, key->rsa->e); + buffer_get_bignum(&e->input, key->rsa->n); + + if (bits != key_size(key)) + log("Warning: identity keysize mismatch: actual %d, announced %d", + key_size(key), bits); + break; + case 2: + blob = buffer_get_string(&e->input, &blen); + key = key_from_blob(blob, blen); + xfree(blob); + break; + } + if (key != NULL) { + int idx; + private = lookup_private_key(key, &idx, version); + if (private != NULL) { + /* + * We have this key. Free the old key. Since we + * 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. + */ + Idtab *tab = idtab_lookup(version); + key_free(tab->identities[idx].key); + xfree(tab->identities[idx].comment); + if (tab->nentries < 1) + fatal("process_remove_identity: " + "internal error: tab->nentries %d", + tab->nentries); + if (idx != tab->nentries - 1) { + int i; + for (i = idx; i < tab->nentries - 1; i++) + tab->identities[i] = tab->identities[i+1]; + } + tab->identities[tab->nentries - 1].key = NULL; + tab->identities[tab->nentries - 1].comment = NULL; + tab->nentries--; + success = 1; + } + key_free(key); + } + buffer_put_int(&e->output, 1); + buffer_put_char(&e->output, + success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); +} + +void +process_remove_all_identities(SocketEntry *e, int version) +{ + u_int i; + Idtab *tab = idtab_lookup(version); + + /* Loop over all identities and clear the keys. */ + for (i = 0; i < tab->nentries; i++) { + key_free(tab->identities[i].key); + xfree(tab->identities[i].comment); + } + + /* Mark that there are no identities. */ + tab->nentries = 0; + + /* Send success. */ + buffer_put_int(&e->output, 1); + buffer_put_char(&e->output, SSH_AGENT_SUCCESS); + return; +} + +void +process_add_identity(SocketEntry *e, int version) +{ + Key *k = NULL; + char *type_name; + char *comment; + int type, success = 0; + Idtab *tab = idtab_lookup(version); + + switch (version) { + case 1: + k = key_new_private(KEY_RSA1); + buffer_get_int(&e->input); /* ignored */ + buffer_get_bignum(&e->input, k->rsa->n); + buffer_get_bignum(&e->input, k->rsa->e); + buffer_get_bignum(&e->input, k->rsa->d); + buffer_get_bignum(&e->input, k->rsa->iqmp); + + /* SSH and SSL have p and q swapped */ + buffer_get_bignum(&e->input, k->rsa->q); /* p */ + buffer_get_bignum(&e->input, k->rsa->p); /* q */ + + /* Generate additional parameters */ + generate_additional_parameters(k->rsa); + break; + case 2: + type_name = buffer_get_string(&e->input, NULL); + type = key_type_from_name(type_name); + xfree(type_name); + switch(type) { + case KEY_DSA: + k = key_new_private(type); + buffer_get_bignum2(&e->input, k->dsa->p); + buffer_get_bignum2(&e->input, k->dsa->q); + buffer_get_bignum2(&e->input, k->dsa->g); + buffer_get_bignum2(&e->input, k->dsa->pub_key); + buffer_get_bignum2(&e->input, k->dsa->priv_key); + break; + case KEY_RSA: + k = key_new_private(type); + buffer_get_bignum2(&e->input, k->rsa->n); + buffer_get_bignum2(&e->input, k->rsa->e); + buffer_get_bignum2(&e->input, k->rsa->d); + buffer_get_bignum2(&e->input, k->rsa->iqmp); + buffer_get_bignum2(&e->input, k->rsa->p); + buffer_get_bignum2(&e->input, k->rsa->q); + + /* Generate additional parameters */ + generate_additional_parameters(k->rsa); + break; + default: + buffer_clear(&e->input); + goto send; + } + break; + } + comment = buffer_get_string(&e->input, NULL); + if (k == NULL) { + xfree(comment); + goto send; + } + success = 1; + if (lookup_private_key(k, NULL, version) == NULL) { + if (tab->nentries == 0) + tab->identities = xmalloc(sizeof(Identity)); + else + tab->identities = xrealloc(tab->identities, + (tab->nentries + 1) * sizeof(Identity)); + tab->identities[tab->nentries].key = k; + tab->identities[tab->nentries].comment = comment; + /* Increment the number of identities. */ + tab->nentries++; + } else { + key_free(k); + xfree(comment); + } +send: + buffer_put_int(&e->output, 1); + buffer_put_char(&e->output, + success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); +} + +/* dispatch incoming messages */ + +void +process_message(SocketEntry *e) +{ + u_int msg_len; + u_int type; + u_char *cp; + if (buffer_len(&e->input) < 5) + return; /* Incomplete message. */ + cp = (u_char *) buffer_ptr(&e->input); + msg_len = GET_32BIT(cp); + if (msg_len > 256 * 1024) { + shutdown(e->fd, SHUT_RDWR); + close(e->fd); + e->type = AUTH_UNUSED; + return; + } + if (buffer_len(&e->input) < msg_len + 4) + return; + buffer_consume(&e->input, 4); + type = buffer_get_char(&e->input); + + switch (type) { + /* ssh1 */ + case SSH_AGENTC_RSA_CHALLENGE: + process_authentication_challenge1(e); + break; + case SSH_AGENTC_REQUEST_RSA_IDENTITIES: + process_request_identities(e, 1); + break; + case SSH_AGENTC_ADD_RSA_IDENTITY: + process_add_identity(e, 1); + break; + case SSH_AGENTC_REMOVE_RSA_IDENTITY: + process_remove_identity(e, 1); + break; + case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES: + process_remove_all_identities(e, 1); + break; + /* ssh2 */ + case SSH2_AGENTC_SIGN_REQUEST: + process_sign_request2(e); + break; + case SSH2_AGENTC_REQUEST_IDENTITIES: + process_request_identities(e, 2); + break; + case SSH2_AGENTC_ADD_IDENTITY: + process_add_identity(e, 2); + break; + case SSH2_AGENTC_REMOVE_IDENTITY: + process_remove_identity(e, 2); + break; + case SSH2_AGENTC_REMOVE_ALL_IDENTITIES: + process_remove_all_identities(e, 2); + break; + default: + /* Unknown message. Respond with failure. */ + error("Unknown message %d", type); + buffer_clear(&e->input); + buffer_put_int(&e->output, 1); + buffer_put_char(&e->output, SSH_AGENT_FAILURE); + break; + } +} + +void +new_socket(int type, int fd) +{ + u_int i, old_alloc; + if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0) + error("fcntl O_NONBLOCK: %s", strerror(errno)); + + 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); + 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++) + sockets[i].type = AUTH_UNUSED; + sockets[old_alloc].type = type; + sockets[old_alloc].fd = fd; + buffer_init(&sockets[old_alloc].input); + buffer_init(&sockets[old_alloc].output); +} + +int +prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl) +{ + u_int i, sz; + int n = 0; + + for (i = 0; i < sockets_alloc; i++) { + switch (sockets[i].type) { + case AUTH_SOCKET: + case AUTH_CONNECTION: + n = MAX(n, sockets[i].fd); + break; + case AUTH_UNUSED: + break; + default: + fatal("Unknown socket type %d", sockets[i].type); + break; + } + } + + sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); + if (*fdrp == NULL || n > *fdl) { + if (*fdrp) + xfree(*fdrp); + if (*fdwp) + xfree(*fdwp); + *fdrp = xmalloc(sz); + *fdwp = xmalloc(sz); + *fdl = n; + } + memset(*fdrp, 0, sz); + memset(*fdwp, 0, sz); + + for (i = 0; i < sockets_alloc; i++) { + switch (sockets[i].type) { + case AUTH_SOCKET: + case AUTH_CONNECTION: + FD_SET(sockets[i].fd, *fdrp); + if (buffer_len(&sockets[i].output) > 0) + FD_SET(sockets[i].fd, *fdwp); + break; + default: + break; + } + } + return (1); +} + +void +after_select(fd_set *readset, fd_set *writeset) +{ + u_int i; + int len, sock; + socklen_t slen; + char buf[1024]; + struct sockaddr_un sunaddr; + + for (i = 0; i < sockets_alloc; i++) + switch (sockets[i].type) { + case AUTH_UNUSED: + break; + case AUTH_SOCKET: + if (FD_ISSET(sockets[i].fd, readset)) { + slen = sizeof(sunaddr); + sock = accept(sockets[i].fd, + (struct sockaddr *) &sunaddr, &slen); + if (sock < 0) { + perror("accept from AUTH_SOCKET"); + break; + } + new_socket(AUTH_CONNECTION, sock); + } + break; + case AUTH_CONNECTION: + if (buffer_len(&sockets[i].output) > 0 && + FD_ISSET(sockets[i].fd, writeset)) { + do { + len = write(sockets[i].fd, + buffer_ptr(&sockets[i].output), + buffer_len(&sockets[i].output)); + if (len == -1 && (errno == EAGAIN || + errno == EINTR)) + continue; + break; + } while (1); + if (len <= 0) { + shutdown(sockets[i].fd, SHUT_RDWR); + close(sockets[i].fd); + sockets[i].type = AUTH_UNUSED; + buffer_free(&sockets[i].input); + buffer_free(&sockets[i].output); + break; + } + buffer_consume(&sockets[i].output, len); + } + if (FD_ISSET(sockets[i].fd, readset)) { + do { + len = read(sockets[i].fd, buf, sizeof(buf)); + if (len == -1 && (errno == EAGAIN || + errno == EINTR)) + continue; + break; + } while (1); + if (len <= 0) { + shutdown(sockets[i].fd, SHUT_RDWR); + close(sockets[i].fd); + sockets[i].type = AUTH_UNUSED; + buffer_free(&sockets[i].input); + buffer_free(&sockets[i].output); + break; + } + buffer_append(&sockets[i].input, buf, len); + process_message(&sockets[i]); + } + break; + default: + fatal("Unknown type %d", sockets[i].type); + } +} + +void +check_parent_exists(int sig) +{ + int save_errno = errno; + + if (parent_pid != -1 && kill(parent_pid, 0) < 0) { + /* printf("Parent has died - Authentication agent exiting.\n"); */ + exit(1); + } + signal(SIGALRM, check_parent_exists); + alarm(10); + errno = save_errno; +} + +void +cleanup_socket(void) +{ + if (socket_name[0]) + unlink(socket_name); + if (socket_dir[0]) + rmdir(socket_dir); +} + +void +cleanup_exit(int i) +{ + cleanup_socket(); + exit(i); +} + +void +cleanup_handler(int sig) +{ + cleanup_socket(); + _exit(2); +} + +void +usage(void) +{ + fprintf(stderr, "ssh-agent version %s\n", SSH_VERSION); + fprintf(stderr, "Usage: %s [-c | -s] [-k] [command {args...]]\n", + __progname); + exit(1); +} + +int +main(int ac, char **av) +{ + int sock, c_flag = 0, k_flag = 0, s_flag = 0, ch; + struct sockaddr_un sunaddr; + struct rlimit rlim; + pid_t pid; + char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid]; + extern int optind; + fd_set *readsetp = NULL, *writesetp = NULL; + + SSLeay_add_all_algorithms(); + + while ((ch = getopt(ac, av, "cks")) != -1) { + switch (ch) { + case 'c': + if (s_flag) + usage(); + c_flag++; + break; + case 'k': + k_flag++; + break; + case 's': + if (c_flag) + usage(); + s_flag++; + break; + default: + usage(); + } + } + ac -= optind; + av += optind; + + if (ac > 0 && (c_flag || k_flag || s_flag)) + usage(); + + if (ac == 0 && !c_flag && !k_flag && !s_flag) { + shell = getenv("SHELL"); + if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0) + c_flag = 1; + } + if (k_flag) { + 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); + exit(1); + } + if (kill(pid, SIGTERM) == -1) { + perror("kill"); + exit(1); + } + format = c_flag ? "unsetenv %s;\n" : "unset %s;\n"; + printf(format, SSH_AUTHSOCKET_ENV_NAME); + printf(format, SSH_AGENTPID_ENV_NAME); + printf("echo Agent pid %d killed;\n", pid); + exit(0); + } + parent_pid = getpid(); + + /* Create private directory for agent socket */ + strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir); + if (mkdtemp(socket_dir) == NULL) { + perror("mkdtemp: private socket dir"); + exit(1); + } + snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir, + parent_pid); + + /* + * Create socket early so it will exist before command gets run from + * the parent. + */ + sock = socket(AF_UNIX, SOCK_STREAM, 0); + if (sock < 0) { + perror("socket"); + cleanup_exit(1); + } + memset(&sunaddr, 0, sizeof(sunaddr)); + sunaddr.sun_family = AF_UNIX; + strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path)); + sunaddr.sun_len = SUN_LEN(&sunaddr) + 1; + if (bind(sock, (struct sockaddr *)&sunaddr, sunaddr.sun_len) < 0) { + perror("bind"); + cleanup_exit(1); + } + if (listen(sock, 5) < 0) { + perror("listen"); + cleanup_exit(1); + } + + /* + * Fork, and have the parent execute the command, if any, or present + * the socket data. The child continues as the authentication agent. + */ + pid = fork(); + if (pid == -1) { + perror("fork"); + exit(1); + } + if (pid != 0) { /* Parent - execute the given command. */ + close(sock); + snprintf(pidstrbuf, sizeof pidstrbuf, "%d", pid); + if (ac == 0) { + format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; + printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, + SSH_AUTHSOCKET_ENV_NAME); + printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf, + SSH_AGENTPID_ENV_NAME); + printf("echo Agent pid %d;\n", pid); + exit(0); + } + if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 || + setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) { + perror("setenv"); + exit(1); + } + execvp(av[0], av); + perror(av[0]); + exit(1); + } + close(0); + close(1); + close(2); + + /* deny core dumps, since memory contains unencrypted private keys */ + rlim.rlim_cur = rlim.rlim_max = 0; + if (setrlimit(RLIMIT_CORE, &rlim) < 0) { + perror("setrlimit rlimit_core failed"); + cleanup_exit(1); + } + if (setsid() == -1) { + perror("setsid"); + cleanup_exit(1); + } + if (atexit(cleanup_socket) < 0) { + perror("atexit"); + cleanup_exit(1); + } + new_socket(AUTH_SOCKET, sock); + if (ac > 0) { + signal(SIGALRM, check_parent_exists); + alarm(10); + } + idtab_init(); + signal(SIGINT, SIG_IGN); + signal(SIGPIPE, SIG_IGN); + signal(SIGHUP, cleanup_handler); + signal(SIGTERM, cleanup_handler); + while (1) { + prepare_select(&readsetp, &writesetp, &max_fd); + if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) { + if (errno == EINTR) + continue; + exit(1); + } + after_select(readsetp, writesetp); + } + /* NOTREACHED */ +} |
