=================================================================== RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/ssh-agent.c,v retrieving revision 1.37 retrieving revision 1.37.2.2 diff -u -r1.37 -r1.37.2.2 --- src/usr.bin/ssh/ssh-agent.c 2000/09/21 11:07:51 1.37 +++ src/usr.bin/ssh/ssh-agent.c 2001/02/19 17:19:27 1.37.2.2 @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh-agent.c,v 1.37 2000/09/21 11:07:51 markus Exp $ */ +/* $OpenBSD: ssh-agent.c,v 1.37.2.2 2001/02/19 17:19:27 jason Exp $ */ /* * Author: Tatu Ylonen @@ -37,8 +37,11 @@ */ #include "includes.h" -RCSID("$OpenBSD: ssh-agent.c,v 1.37 2000/09/21 11:07:51 markus Exp $"); +RCSID("$OpenBSD: ssh-agent.c,v 1.37.2.2 2001/02/19 17:19:27 jason Exp $"); +#include +#include + #include "ssh.h" #include "rsa.h" #include "buffer.h" @@ -47,16 +50,12 @@ #include "packet.h" #include "getput.h" #include "mpaux.h" - -#include -#include -#include -#include #include "key.h" #include "authfd.h" -#include "dsa.h" +#include "cipher.h" #include "kex.h" #include "compat.h" +#include "log.h" typedef struct { int fd; @@ -67,7 +66,7 @@ Buffer output; } SocketEntry; -unsigned int sockets_alloc = 0; +u_int sockets_alloc = 0; SocketEntry *sockets = NULL; typedef struct { @@ -94,6 +93,8 @@ extern char *__progname; +int prepare_select(fd_set **, fd_set **, int *); + void idtab_init(void) { @@ -143,14 +144,14 @@ buffer_put_int(&msg, tab->nentries); for (i = 0; i < tab->nentries; i++) { Identity *id = &tab->identities[i]; - if (id->key->type == KEY_RSA) { + 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 { - unsigned char *blob; - unsigned int blen; - dsa_make_key_blob(id->key, &blob, &blen); + u_char *blob; + u_int blen; + key_to_blob(id->key, &blob, &blen); buffer_put_string(&msg, blob, blen); xfree(blob); } @@ -170,11 +171,11 @@ int i, len; Buffer msg; MD5_CTX md; - unsigned char buf[32], mdbuf[16], session_id[16]; - unsigned int response_type; + u_char buf[32], mdbuf[16], session_id[16]; + u_int response_type; buffer_init(&msg); - key = key_new(KEY_RSA); + key = key_new(KEY_RSA1); challenge = BN_new(); buffer_get_int(&e->input); /* ignored */ @@ -193,7 +194,8 @@ private = lookup_private_key(key, NULL, 1); if (private != NULL) { /* Decrypt the challenge using the private key. */ - rsa_private_decrypt(challenge, challenge, private->rsa); + 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); @@ -232,14 +234,14 @@ { extern int datafellows; Key *key, *private; - unsigned char *blob, *data, *signature = NULL; - unsigned int blen, dlen, slen = 0; + 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); @@ -247,11 +249,11 @@ if (flags & SSH_AGENT_OLD_SIGNATURE) datafellows = SSH_BUG_SIGBLOB; - key = dsa_key_from_blob(blob, blen); + key = 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); + ok = key_sign(private, &signature, &slen, data, dlen); } key_free(key); buffer_init(&msg); @@ -276,25 +278,25 @@ process_remove_identity(SocketEntry *e, int version) { Key *key = NULL, *private; - unsigned char *blob; - unsigned int blen; - unsigned int bits; + u_char *blob; + u_int blen; + u_int bits; int success = 0; switch(version){ case 1: - key = key_new(KEY_RSA); + 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); + key_size(key), bits); break; case 2: blob = buffer_get_string(&e->input, &blen); - key = dsa_key_from_blob(blob, blen); + key = key_from_blob(blob, blen); xfree(blob); break; } @@ -305,14 +307,24 @@ /* * 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. + * 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 (idx != tab->nentries) - tab->identities[idx] = tab->identities[tab->nentries]; + 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; } @@ -326,7 +338,7 @@ void process_remove_all_identities(SocketEntry *e, int version) { - unsigned int i; + u_int i; Idtab *tab = idtab_lookup(version); /* Loop over all identities and clear the keys. */ @@ -345,79 +357,80 @@ } void -process_add_identity(SocketEntry *e, int version) +generate_additional_parameters(RSA *rsa) { - Key *k = NULL; - RSA *rsa; BIGNUM *aux; BN_CTX *ctx; - char *type; + /* 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); +} + +void +process_add_identity(SocketEntry *e, int version) +{ + Key *k = NULL; + char *type_name; char *comment; - int success = 0; + int type, success = 0; Idtab *tab = idtab_lookup(version); switch (version) { case 1: - k = key_new(KEY_RSA); - rsa = k->rsa; + 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); - /* 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 */ + buffer_get_bignum(&e->input, k->rsa->q); /* p */ + buffer_get_bignum(&e->input, k->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); - + generate_additional_parameters(k->rsa); break; case 2: - type = buffer_get_string(&e->input, NULL); - if (strcmp(type, KEX_DSS)) { + 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); - 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); @@ -449,12 +462,12 @@ void process_message(SocketEntry *e) { - unsigned int msg_len; - unsigned int type; - unsigned char *cp; + u_int msg_len; + u_int type; + u_char *cp; if (buffer_len(&e->input) < 5) return; /* Incomplete message. */ - cp = (unsigned char *) buffer_ptr(&e->input); + cp = (u_char *) buffer_ptr(&e->input); msg_len = GET_32BIT(cp); if (msg_len > 256 * 1024) { shutdown(e->fd, SHUT_RDWR); @@ -513,7 +526,7 @@ void new_socket(int type, int fd) { - unsigned int i, old_alloc; + u_int i, old_alloc; if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0) error("fcntl O_NONBLOCK: %s", strerror(errno)); @@ -542,17 +555,17 @@ buffer_init(&sockets[old_alloc].output); } -void -prepare_select(fd_set *readset, fd_set *writeset) +int +prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl) { - unsigned int i; - for (i = 0; i < sockets_alloc; i++) + u_int i, sz; + int n = 0; + + 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); + n = MAX(n, sockets[i].fd); break; case AUTH_UNUSED: break; @@ -560,12 +573,40 @@ fatal("Unknown socket type %d", sockets[i].type); break; } + } + + sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); + if (*fdrp == NULL || n > *fdl) { + if (*fdrp) + free(*fdrp); + if (*fdwp) + free(*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) { - unsigned int i; + u_int i; int len, sock; socklen_t slen; char buf[1024]; @@ -578,7 +619,8 @@ case AUTH_SOCKET: if (FD_ISSET(sockets[i].fd, readset)) { slen = sizeof(sunaddr); - sock = accept(sockets[i].fd, (struct sockaddr *) & sunaddr, &slen); + sock = accept(sockets[i].fd, + (struct sockaddr *) &sunaddr, &slen); if (sock < 0) { perror("accept from AUTH_SOCKET"); break; @@ -589,8 +631,9 @@ 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)); + 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); @@ -623,19 +666,24 @@ 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) { - remove(socket_name); - rmdir(socket_dir); + if (socket_name[0]) + unlink(socket_name); + if (socket_dir[0]) + rmdir(socket_dir); } void @@ -646,30 +694,32 @@ } void -usage() +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); + __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; + struct rlimit rlim; pid_t pid; char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid]; + extern int optind; + fd_set *readsetp = NULL, *writesetp = NULL; - /* 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': @@ -704,14 +754,13 @@ pidstr = getenv(SSH_AGENTPID_ENV_NAME); if (pidstr == NULL) { fprintf(stderr, "%s not set, cannot kill agent\n", - SSH_AGENTPID_ENV_NAME); + SSH_AGENTPID_ENV_NAME); exit(1); } pid = atoi(pidstr); - if (pid < 1) { /* XXX PID_MAX check too */ - /* Yes, PID_MAX check please */ + if (pid < 1) { fprintf(stderr, "%s=\"%s\", which is not a good PID\n", - SSH_AGENTPID_ENV_NAME, pidstr); + SSH_AGENTPID_ENV_NAME, pidstr); exit(1); } if (kill(pid, SIGTERM) == -1) { @@ -733,7 +782,7 @@ exit(1); } snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir, - parent_pid); + parent_pid); /* * Create socket early so it will exist before command gets run from @@ -755,6 +804,7 @@ 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. @@ -770,9 +820,9 @@ 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); + SSH_AUTHSOCKET_ENV_NAME); printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf, - SSH_AGENTPID_ENV_NAME); + SSH_AGENTPID_ENV_NAME); printf("echo Agent pid %d;\n", pid); exit(0); } @@ -789,6 +839,12 @@ 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); @@ -805,18 +861,16 @@ idtab_init(); signal(SIGINT, SIG_IGN); signal(SIGPIPE, SIG_IGN); - signal(SIGHUP, cleanup_exit); - signal(SIGTERM, cleanup_exit); + signal(SIGHUP, cleanup_handler); + signal(SIGTERM, cleanup_handler); while (1) { - FD_ZERO(&readset); - FD_ZERO(&writeset); - prepare_select(&readset, &writeset); - if (select(max_fd + 1, &readset, &writeset, NULL, NULL) < 0) { + prepare_select(&readsetp, &writesetp, &max_fd); + if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) { if (errno == EINTR) continue; exit(1); } - after_select(&readset, &writeset); + after_select(readsetp, writesetp); } /* NOTREACHED */ }