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-rw-r--r--crypto/openssh/ssh-agent.c825
1 files changed, 825 insertions, 0 deletions
diff --git a/crypto/openssh/ssh-agent.c b/crypto/openssh/ssh-agent.c
new file mode 100644
index 0000000..bbd6a78
--- /dev/null
+++ b/crypto/openssh/ssh-agent.c
@@ -0,0 +1,825 @@
+/* $OpenBSD: ssh-agent.c,v 1.37 2000/09/21 11:07:51 markus 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 1.37 2000/09/21 11:07:51 markus Exp $");
+RCSID("$FreeBSD$");
+
+#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 <openssl/evp.h>
+#include <openssl/md5.h>
+#include <openssl/dsa.h>
+#include <openssl/rsa.h>
+#include "key.h"
+#include "authfd.h"
+#include "dsa.h"
+#include "kex.h"
+#include "compat.h"
+
+typedef struct {
+ int fd;
+ enum {
+ AUTH_UNUSED, AUTH_SOCKET, AUTH_CONNECTION
+ } type;
+ Buffer input;
+ Buffer output;
+} SocketEntry;
+
+unsigned 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;
+
+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_RSA) {
+ 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 {
+ unsigned char *blob;
+ unsigned int blen;
+ dsa_make_key_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;
+ unsigned char buf[32], mdbuf[16], session_id[16];
+ unsigned int response_type;
+
+ buffer_init(&msg);
+ key = key_new(KEY_RSA);
+ 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;
+ unsigned char *blob, *data, *signature = NULL;
+ unsigned 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 = dsa_key_from_blob(blob, blen);
+ if (key != NULL) {
+ private = lookup_private_key(key, NULL, 2);
+ if (private != NULL)
+ ok = dsa_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;
+ unsigned char *blob;
+ unsigned int blen;
+ unsigned int bits;
+ int success = 0;
+
+ switch(version){
+ case 1:
+ key = key_new(KEY_RSA);
+ 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 = dsa_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 copy
+ * data from the last entry.
+ */
+ Idtab *tab = idtab_lookup(version);
+ key_free(tab->identities[idx].key);
+ xfree(tab->identities[idx].comment);
+ if (idx != tab->nentries)
+ tab->identities[idx] = tab->identities[tab->nentries];
+ 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)
+{
+ unsigned 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;
+ RSA *rsa;
+ BIGNUM *aux;
+ BN_CTX *ctx;
+ char *type;
+ char *comment;
+ int success = 0;
+ Idtab *tab = idtab_lookup(version);
+
+ switch (version) {
+ case 1:
+ k = key_new(KEY_RSA);
+ rsa = k->rsa;
+
+ /* allocate mem for private key */
+ /* XXX rsa->n and rsa->e are already allocated */
+ rsa->d = BN_new();
+ rsa->iqmp = BN_new();
+ rsa->q = BN_new();
+ rsa->p = BN_new();
+ rsa->dmq1 = BN_new();
+ rsa->dmp1 = BN_new();
+
+ buffer_get_int(&e->input); /* ignored */
+
+ buffer_get_bignum(&e->input, rsa->n);
+ buffer_get_bignum(&e->input, rsa->e);
+ buffer_get_bignum(&e->input, rsa->d);
+ buffer_get_bignum(&e->input, rsa->iqmp);
+
+ /* SSH and SSL have p and q swapped */
+ buffer_get_bignum(&e->input, rsa->q); /* p */
+ buffer_get_bignum(&e->input, rsa->p); /* q */
+
+ /* Generate additional parameters */
+ aux = BN_new();
+ ctx = BN_CTX_new();
+
+ BN_sub(aux, rsa->q, BN_value_one());
+ BN_mod(rsa->dmq1, rsa->d, aux, ctx);
+
+ BN_sub(aux, rsa->p, BN_value_one());
+ BN_mod(rsa->dmp1, rsa->d, aux, ctx);
+
+ BN_clear_free(aux);
+ BN_CTX_free(ctx);
+
+ break;
+ case 2:
+ type = buffer_get_string(&e->input, NULL);
+ if (strcmp(type, KEX_DSS)) {
+ buffer_clear(&e->input);
+ xfree(type);
+ goto send;
+ }
+ xfree(type);
+
+ k = key_new(KEY_DSA);
+
+ /* allocate mem for private key */
+ k->dsa->priv_key = BN_new();
+
+ 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;
+ }
+
+ 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)
+{
+ unsigned int msg_len;
+ unsigned int type;
+ unsigned char *cp;
+ if (buffer_len(&e->input) < 5)
+ return; /* Incomplete message. */
+ cp = (unsigned 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)
+{
+ unsigned 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);
+}
+
+void
+prepare_select(fd_set *readset, fd_set *writeset)
+{
+ unsigned int i;
+ for (i = 0; i < sockets_alloc; i++)
+ switch (sockets[i].type) {
+ case AUTH_SOCKET:
+ case AUTH_CONNECTION:
+ FD_SET(sockets[i].fd, readset);
+ if (buffer_len(&sockets[i].output) > 0)
+ FD_SET(sockets[i].fd, writeset);
+ break;
+ case AUTH_UNUSED:
+ break;
+ default:
+ fatal("Unknown socket type %d", sockets[i].type);
+ break;
+ }
+}
+
+void
+after_select(fd_set *readset, fd_set *writeset)
+{
+ unsigned 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)) {
+ len = write(sockets[i].fd, buffer_ptr(&sockets[i].output),
+ buffer_len(&sockets[i].output));
+ 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)) {
+ len = read(sockets[i].fd, buf, sizeof(buf));
+ 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)
+{
+ 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);
+}
+
+void
+cleanup_socket(void)
+{
+ remove(socket_name);
+ rmdir(socket_dir);
+}
+
+void
+cleanup_exit(int i)
+{
+ cleanup_socket();
+ exit(i);
+}
+
+void
+usage()
+{
+ 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)
+{
+ fd_set readset, writeset;
+ int sock, c_flag = 0, k_flag = 0, s_flag = 0, ch;
+ struct sockaddr_un sunaddr;
+ pid_t pid;
+ char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
+
+ /* check if RSA support exists */
+ if (rsa_alive() == 0) {
+ fprintf(stderr,
+ "%s: no RSA support in libssl and libcrypto. See ssl(8).\n",
+ __progname);
+ exit(1);
+ }
+ 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) { /* XXX PID_MAX check too */
+ /* Yes, PID_MAX check please */
+ 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);
+
+ 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_exit);
+ signal(SIGTERM, cleanup_exit);
+ while (1) {
+ FD_ZERO(&readset);
+ FD_ZERO(&writeset);
+ prepare_select(&readset, &writeset);
+ if (select(max_fd + 1, &readset, &writeset, NULL, NULL) < 0) {
+ if (errno == EINTR)
+ continue;
+ exit(1);
+ }
+ after_select(&readset, &writeset);
+ }
+ /* NOTREACHED */
+}
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