=================================================================== RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/ssh-agent.c,v retrieving revision 1.31 retrieving revision 1.31.2.4 diff -u -r1.31 -r1.31.2.4 --- src/usr.bin/ssh/ssh-agent.c 2000/04/29 18:11:52 1.31 +++ src/usr.bin/ssh/ssh-agent.c 2001/03/21 18:53:08 1.31.2.4 @@ -1,28 +1,62 @@ -/* $OpenBSD: ssh-agent.c,v 1.31 2000/04/29 18:11:52 markus Exp $ */ +/* $OpenBSD: ssh-agent.c,v 1.31.2.4 2001/03/21 18:53:08 jason Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland * All rights reserved - * Created: Wed Mar 29 03:46:59 1995 ylo * 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 1.31 2000/04/29 18:11:52 markus Exp $"); +RCSID("$OpenBSD: ssh-agent.c,v 1.31.2.4 2001/03/21 18:53:08 jason Exp $"); +#include +#include + #include "ssh.h" #include "rsa.h" -#include "authfd.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" -#include - typedef struct { int fd; enum { @@ -32,17 +66,22 @@ Buffer output; } SocketEntry; -unsigned int sockets_alloc = 0; +u_int sockets_alloc = 0; SocketEntry *sockets = NULL; typedef struct { - RSA *key; + Key *key; char *comment; } Identity; -unsigned int num_identities = 0; -Identity *identities = NULL; +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 */ @@ -54,176 +93,262 @@ extern char *__progname; +int prepare_select(fd_set **, fd_set **, int *); + void -process_request_identity(SocketEntry *e) +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, SSH_AGENT_RSA_IDENTITIES_ANSWER); - buffer_put_int(&msg, num_identities); - for (i = 0; i < num_identities; i++) { - buffer_put_int(&msg, BN_num_bits(identities[i].key->n)); - buffer_put_bignum(&msg, identities[i].key->e); - buffer_put_bignum(&msg, identities[i].key->n); - buffer_put_string(&msg, identities[i].comment, - strlen(identities[i].comment)); + 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_challenge(SocketEntry *e) +process_authentication_challenge1(SocketEntry *e) { - int i, pub_bits, len; - BIGNUM *pub_e, *pub_n, *challenge; + 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; + u_char buf[32], mdbuf[16], session_id[16]; + u_int response_type; buffer_init(&msg); - pub_e = BN_new(); - pub_n = BN_new(); + key = key_new(KEY_RSA1); challenge = BN_new(); - pub_bits = buffer_get_int(&e->input); - buffer_get_bignum(&e->input, pub_e); - buffer_get_bignum(&e->input, pub_n); + + 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); - if (buffer_len(&e->input) == 0) { - /* Compatibility code for old servers. */ - memset(session_id, 0, 16); - response_type = 0; - } else { - /* New code. */ - buffer_get(&e->input, (char *) session_id, 16); - response_type = buffer_get_int(&e->input); - } - for (i = 0; i < num_identities; i++) - if (pub_bits == BN_num_bits(identities[i].key->n) && - BN_cmp(pub_e, identities[i].key->e) == 0 && - BN_cmp(pub_n, identities[i].key->n) == 0) { - /* Decrypt the challenge using the private key. */ - rsa_private_decrypt(challenge, challenge, identities[i].key); - /* Compute the desired response. */ - switch (response_type) { - case 0:/* As of protocol 1.0 */ - /* This response type is no longer supported. */ - log("Compatibility with ssh protocol 1.0 no longer supported."); - buffer_put_char(&msg, SSH_AGENT_FAILURE); - goto send; + /* 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; - case 1:/* As of protocol 1.1 */ - /* The response is MD5 of decrypted challenge plus session id. */ - len = BN_num_bytes(challenge); + 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; - if (len <= 0 || len > 32) { - fatal("process_authentication_challenge: " - "bad challenge length %d", len); - } - 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); - break; + /* 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); - default: - fatal("process_authentication_challenge: bad response_type %d", - response_type); - break; - } + /* 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; + } - /* 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; - } - /* Unknown identity. Send failure. */ +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)); - buffer_free(&msg); - BN_clear_free(pub_e); - BN_clear_free(pub_n); + buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); + key_free(key); BN_clear_free(challenge); + buffer_free(&msg); } +/* ssh2 only */ void -process_remove_identity(SocketEntry *e) +process_sign_request2(SocketEntry *e) { - unsigned int bits; - unsigned int i; - BIGNUM *dummy, *n; + 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; - dummy = BN_new(); - n = BN_new(); + datafellows = 0; - /* Get the key from the packet. */ - bits = buffer_get_int(&e->input); - buffer_get_bignum(&e->input, dummy); - buffer_get_bignum(&e->input, n); + blob = buffer_get_string(&e->input, &blen); + data = buffer_get_string(&e->input, &dlen); - if (bits != BN_num_bits(n)) - log("Warning: identity keysize mismatch: actual %d, announced %d", - BN_num_bits(n), bits); + flags = buffer_get_int(&e->input); + if (flags & SSH_AGENT_OLD_SIGNATURE) + datafellows = SSH_BUG_SIGBLOB; - /* Check if we have the key. */ - for (i = 0; i < num_identities; i++) - if (BN_cmp(identities[i].key->n, n) == 0) { + 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 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. */ - RSA_free(identities[i].key); - xfree(identities[i].comment); - if (i < num_identities - 1) - identities[i] = identities[num_identities - 1]; - num_identities--; - BN_clear_free(dummy); - BN_clear_free(n); - - /* Send success. */ - buffer_put_int(&e->output, 1); - buffer_put_char(&e->output, SSH_AGENT_SUCCESS); - return; + 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; } - /* We did not have the key. */ - BN_clear(dummy); - BN_clear(n); - - /* Send failure. */ + key_free(key); + } buffer_put_int(&e->output, 1); - buffer_put_char(&e->output, SSH_AGENT_FAILURE); + buffer_put_char(&e->output, + success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); } -/* - * Removes all identities from the agent. - */ void -process_remove_all_identities(SocketEntry *e) +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. */ - for (i = 0; i < num_identities; i++) { - RSA_free(identities[i].key); - xfree(identities[i].comment); + for (i = 0; i < tab->nentries; i++) { + key_free(tab->identities[i].key); + xfree(tab->identities[i].comment); } /* Mark that there are no identities. */ - num_identities = 0; + tab->nentries = 0; /* Send success. */ buffer_put_int(&e->output, 1); @@ -231,88 +356,118 @@ return; } -/* - * Adds an identity to the agent. - */ void -process_add_identity(SocketEntry *e) +generate_additional_parameters(RSA *rsa) { - RSA *k; - int i; BIGNUM *aux; BN_CTX *ctx; - - if (num_identities == 0) - identities = xmalloc(sizeof(Identity)); - else - identities = xrealloc(identities, (num_identities + 1) * sizeof(Identity)); - - identities[num_identities].key = RSA_new(); - k = identities[num_identities].key; - buffer_get_int(&e->input); /* bits */ - k->n = BN_new(); - buffer_get_bignum(&e->input, k->n); - k->e = BN_new(); - buffer_get_bignum(&e->input, k->e); - k->d = BN_new(); - buffer_get_bignum(&e->input, k->d); - k->iqmp = BN_new(); - buffer_get_bignum(&e->input, k->iqmp); - /* SSH and SSL have p and q swapped */ - k->q = BN_new(); - buffer_get_bignum(&e->input, k->q); /* p */ - k->p = BN_new(); - buffer_get_bignum(&e->input, k->p); /* q */ - /* Generate additional parameters */ aux = BN_new(); ctx = BN_CTX_new(); - BN_sub(aux, k->q, BN_value_one()); - k->dmq1 = BN_new(); - BN_mod(k->dmq1, k->d, aux, ctx); + BN_sub(aux, rsa->q, BN_value_one()); + BN_mod(rsa->dmq1, rsa->d, aux, ctx); - BN_sub(aux, k->p, BN_value_one()); - k->dmp1 = BN_new(); - BN_mod(k->dmp1, k->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); +} - identities[num_identities].comment = buffer_get_string(&e->input, NULL); +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); - /* Check if we already have the key. */ - for (i = 0; i < num_identities; i++) - if (BN_cmp(identities[i].key->n, k->n) == 0) { - /* - * We already have this key. Clear and free the new - * data and return success. - */ - RSA_free(k); - xfree(identities[num_identities].comment); + 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); - /* Send success. */ - buffer_put_int(&e->output, 1); - buffer_put_char(&e->output, SSH_AGENT_SUCCESS); - return; - } - /* Increment the number of identities. */ - num_identities++; + /* 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 */ - /* Send a success message. */ + /* 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, SSH_AGENT_SUCCESS); + 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; + 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); @@ -326,21 +481,38 @@ type = buffer_get_char(&e->input); switch (type) { - case SSH_AGENTC_REQUEST_RSA_IDENTITIES: - process_request_identity(e); - break; + /* ssh1 */ case SSH_AGENTC_RSA_CHALLENGE: - process_authentication_challenge(e); + 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); + process_add_identity(e, 1); break; case SSH_AGENTC_REMOVE_RSA_IDENTITY: - process_remove_identity(e); + process_remove_identity(e, 1); break; case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES: - process_remove_all_identities(e); + 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); @@ -354,7 +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)); @@ -383,17 +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; @@ -401,12 +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]; @@ -419,7 +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; @@ -430,8 +631,15 @@ 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)); + 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); @@ -443,7 +651,13 @@ buffer_consume(&sockets[i].output, len); } if (FD_ISSET(sockets[i].fd, readset)) { - len = read(sockets[i].fd, buf, sizeof(buf)); + 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); @@ -464,19 +678,24 @@ 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 @@ -487,30 +706,32 @@ } 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': @@ -545,14 +766,13 @@ 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) { @@ -574,7 +794,7 @@ 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 @@ -596,6 +816,7 @@ 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. @@ -611,14 +832,17 @@ 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); } - setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1); - setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1); + 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); @@ -627,6 +851,12 @@ 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); @@ -640,20 +870,19 @@ 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); + 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 */ }