X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/c345cf9d1095299a9077386c1188a86090d385a9..42f11eb24fa39e437b4f1e6beb5cc83901aa5bdd:/authfd.c diff --git a/authfd.c b/authfd.c index a34e111a..17f5d139 100644 --- a/authfd.c +++ b/authfd.c @@ -1,20 +1,43 @@ /* - * - * authfd.c - * * Author: Tatu Ylonen - * * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland * All rights reserved + * Functions for connecting the local authentication agent. * - * Created: Wed Mar 29 01:30:28 1995 ylo + * 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". * - * Functions for connecting the local authentication agent. + * 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: authfd.c,v 1.24 2000/08/15 19:20:46 markus Exp $"); +RCSID("$OpenBSD: authfd.c,v 1.33 2001/01/21 19:05:44 markus Exp $"); + +#include #include "ssh.h" #include "rsa.h" @@ -22,21 +45,26 @@ RCSID("$OpenBSD: authfd.c,v 1.24 2000/08/15 19:20:46 markus Exp $"); #include "bufaux.h" #include "xmalloc.h" #include "getput.h" - -#include -#include -#include #include "key.h" #include "authfd.h" +#include "cipher.h" #include "kex.h" +#include "compat.h" +#include "log.h" +#include "atomicio.h" +#include "authfd.h" /* helper */ int decode_reply(int type); +/* macro to check for "agent failure" message */ +#define agent_failed(x) \ + ((x == SSH_AGENT_FAILURE) || (x == SSH_COM_AGENT2_FAILURE)) + /* Returns the number of the authentication fd, or -1 if there is none. */ int -ssh_get_authentication_socket() +ssh_get_authentication_socket(void) { const char *authsocket; int sock, len; @@ -71,8 +99,7 @@ ssh_get_authentication_socket() } int -ssh_request_reply(AuthenticationConnection *auth, - Buffer *request, Buffer *reply) +ssh_request_reply(AuthenticationConnection *auth, Buffer *request, Buffer *reply) { int l, len; char buf[1024]; @@ -146,7 +173,7 @@ ssh_close_authentication_socket(int sock) */ AuthenticationConnection * -ssh_get_authentication_connection() +ssh_get_authentication_connection(void) { AuthenticationConnection *auth; int sock; @@ -162,7 +189,6 @@ ssh_get_authentication_connection() auth = xmalloc(sizeof(*auth)); auth->fd = sock; - buffer_init(&auth->packet); buffer_init(&auth->identities); auth->howmany = 0; @@ -175,34 +201,42 @@ ssh_get_authentication_connection() */ void -ssh_close_authentication_connection(AuthenticationConnection *ac) +ssh_close_authentication_connection(AuthenticationConnection *auth) { - buffer_free(&ac->packet); - buffer_free(&ac->identities); - close(ac->fd); - xfree(ac); + buffer_free(&auth->identities); + close(auth->fd); + xfree(auth); } /* * Returns the first authentication identity held by the agent. - * Returns true if an identity is available, 0 otherwise. - * The caller must initialize the integers before the call, and free the - * comment after a successful call (before calling ssh_get_next_identity). */ int -ssh_get_first_identity(AuthenticationConnection *auth, - BIGNUM *e, BIGNUM *n, char **comment) +ssh_get_num_identities(AuthenticationConnection *auth, int version) { + int type, code1 = 0, code2 = 0; Buffer request; - int type; + + switch(version){ + case 1: + code1 = SSH_AGENTC_REQUEST_RSA_IDENTITIES; + code2 = SSH_AGENT_RSA_IDENTITIES_ANSWER; + break; + case 2: + code1 = SSH2_AGENTC_REQUEST_IDENTITIES; + code2 = SSH2_AGENT_IDENTITIES_ANSWER; + break; + default: + return 0; + } /* * Send a message to the agent requesting for a list of the * identities it can represent. */ buffer_init(&request); - buffer_put_char(&request, SSH_AGENTC_REQUEST_RSA_IDENTITIES); + buffer_put_char(&request, code1); buffer_clear(&auth->identities); if (ssh_request_reply(auth, &request, &auth->identities) == 0) { @@ -213,8 +247,11 @@ ssh_get_first_identity(AuthenticationConnection *auth, /* Get message type, and verify that we got a proper answer. */ type = buffer_get_char(&auth->identities); - if (type != SSH_AGENT_RSA_IDENTITIES_ANSWER) + if (agent_failed(type)) { + return 0; + } else if (type != code2) { fatal("Bad authentication reply message type: %d", type); + } /* Get the number of entries in the response and check it for sanity. */ auth->howmany = buffer_get_int(&auth->identities); @@ -222,44 +259,58 @@ ssh_get_first_identity(AuthenticationConnection *auth, fatal("Too many identities in authentication reply: %d\n", auth->howmany); - /* Return the first entry (if any). */ - return ssh_get_next_identity(auth, e, n, comment); + return auth->howmany; } -/* - * Returns the next authentication identity for the agent. Other functions - * can be called between this and ssh_get_first_identity or two calls of this - * function. This returns 0 if there are no more identities. The caller - * must free comment after a successful return. - */ +Key * +ssh_get_first_identity(AuthenticationConnection *auth, char **comment, int version) +{ + /* get number of identities and return the first entry (if any). */ + if (ssh_get_num_identities(auth, version) > 0) + return ssh_get_next_identity(auth, comment, version); + return NULL; +} -int -ssh_get_next_identity(AuthenticationConnection *auth, - BIGNUM *e, BIGNUM *n, char **comment) +Key * +ssh_get_next_identity(AuthenticationConnection *auth, char **comment, int version) { - unsigned int bits; + u_int bits; + u_char *blob; + u_int blen; + Key *key = NULL; /* Return failure if no more entries. */ if (auth->howmany <= 0) - return 0; + return NULL; /* * Get the next entry from the packet. These will abort with a fatal * error if the packet is too short or contains corrupt data. */ - bits = buffer_get_int(&auth->identities); - buffer_get_bignum(&auth->identities, e); - buffer_get_bignum(&auth->identities, n); - *comment = buffer_get_string(&auth->identities, NULL); - - if (bits != BN_num_bits(n)) - log("Warning: identity keysize mismatch: actual %d, announced %u", - BN_num_bits(n), bits); - + switch(version){ + case 1: + key = key_new(KEY_RSA1); + bits = buffer_get_int(&auth->identities); + buffer_get_bignum(&auth->identities, key->rsa->e); + buffer_get_bignum(&auth->identities, key->rsa->n); + *comment = buffer_get_string(&auth->identities, NULL); + if (bits != BN_num_bits(key->rsa->n)) + log("Warning: identity keysize mismatch: actual %d, announced %u", + BN_num_bits(key->rsa->n), bits); + break; + case 2: + blob = buffer_get_string(&auth->identities, &blen); + *comment = buffer_get_string(&auth->identities, NULL); + key = key_from_blob(blob, blen); + xfree(blob); + break; + default: + return NULL; + break; + } /* Decrement the number of remaining entries. */ auth->howmany--; - - return 1; + return key; } /* @@ -272,25 +323,27 @@ ssh_get_next_identity(AuthenticationConnection *auth, int ssh_decrypt_challenge(AuthenticationConnection *auth, - BIGNUM* e, BIGNUM *n, BIGNUM *challenge, - unsigned char session_id[16], - unsigned int response_type, - unsigned char response[16]) + Key* key, BIGNUM *challenge, + u_char session_id[16], + u_int response_type, + u_char response[16]) { Buffer buffer; int success = 0; int i; int type; - if (response_type == 0) - fatal("Compatibility with ssh protocol version " - "1.0 no longer supported."); - + if (key->type != KEY_RSA1) + return 0; + if (response_type == 0) { + log("Compatibility with ssh protocol version 1.0 no longer supported."); + return 0; + } buffer_init(&buffer); buffer_put_char(&buffer, SSH_AGENTC_RSA_CHALLENGE); - buffer_put_int(&buffer, BN_num_bits(n)); - buffer_put_bignum(&buffer, e); - buffer_put_bignum(&buffer, n); + buffer_put_int(&buffer, BN_num_bits(key->rsa->n)); + buffer_put_bignum(&buffer, key->rsa->e); + buffer_put_bignum(&buffer, key->rsa->n); buffer_put_bignum(&buffer, challenge); buffer_append(&buffer, (char *) session_id, 16); buffer_put_int(&buffer, response_type); @@ -301,7 +354,7 @@ ssh_decrypt_challenge(AuthenticationConnection *auth, } type = buffer_get_char(&buffer); - if (type == SSH_AGENT_FAILURE) { + if (agent_failed(type)) { log("Agent admitted failure to authenticate using the key."); } else if (type != SSH_AGENT_RSA_RESPONSE) { fatal("Bad authentication response: %d", type); @@ -318,10 +371,54 @@ ssh_decrypt_challenge(AuthenticationConnection *auth, return success; } +/* ask agent to sign data, returns -1 on error, 0 on success */ +int +ssh_agent_sign(AuthenticationConnection *auth, + Key *key, + u_char **sigp, int *lenp, + u_char *data, int datalen) +{ + extern int datafellows; + Buffer msg; + u_char *blob; + u_int blen; + int type, flags = 0; + int ret = -1; + + if (key_to_blob(key, &blob, &blen) == 0) + return -1; + + if (datafellows & SSH_BUG_SIGBLOB) + flags = SSH_AGENT_OLD_SIGNATURE; + + buffer_init(&msg); + buffer_put_char(&msg, SSH2_AGENTC_SIGN_REQUEST); + buffer_put_string(&msg, blob, blen); + buffer_put_string(&msg, data, datalen); + buffer_put_int(&msg, flags); + xfree(blob); + + if (ssh_request_reply(auth, &msg, &msg) == 0) { + buffer_free(&msg); + return -1; + } + type = buffer_get_char(&msg); + if (agent_failed(type)) { + log("Agent admitted failure to sign using the key."); + } else if (type != SSH2_AGENT_SIGN_RESPONSE) { + fatal("Bad authentication response: %d", type); + } else { + ret = 0; + *sigp = buffer_get_string(&msg, lenp); + } + buffer_free(&msg); + return ret; +} + /* Encode key for a message to the agent. */ void -ssh_encode_identity_rsa(Buffer *b, RSA *key, const char *comment) +ssh_encode_identity_rsa1(Buffer *b, RSA *key, const char *comment) { buffer_clear(b); buffer_put_char(b, SSH_AGENTC_ADD_RSA_IDENTITY); @@ -337,17 +434,29 @@ ssh_encode_identity_rsa(Buffer *b, RSA *key, const char *comment) } void -ssh_encode_identity_dsa(Buffer *b, DSA *key, const char *comment) +ssh_encode_identity_ssh2(Buffer *b, Key *key, const char *comment) { buffer_clear(b); buffer_put_char(b, SSH2_AGENTC_ADD_IDENTITY); - buffer_put_cstring(b, KEX_DSS); - buffer_put_bignum2(b, key->p); - buffer_put_bignum2(b, key->q); - buffer_put_bignum2(b, key->g); - buffer_put_bignum2(b, key->pub_key); - buffer_put_bignum2(b, key->priv_key); - buffer_put_string(b, comment, strlen(comment)); + buffer_put_cstring(b, key_ssh_name(key)); + switch(key->type){ + case KEY_RSA: + buffer_put_bignum2(b, key->rsa->n); + buffer_put_bignum2(b, key->rsa->e); + buffer_put_bignum2(b, key->rsa->d); + buffer_put_bignum2(b, key->rsa->iqmp); + buffer_put_bignum2(b, key->rsa->p); + buffer_put_bignum2(b, key->rsa->q); + break; + case KEY_DSA: + buffer_put_bignum2(b, key->dsa->p); + buffer_put_bignum2(b, key->dsa->q); + buffer_put_bignum2(b, key->dsa->g); + buffer_put_bignum2(b, key->dsa->pub_key); + buffer_put_bignum2(b, key->dsa->priv_key); + break; + } + buffer_put_cstring(b, comment); } /* @@ -358,29 +467,30 @@ ssh_encode_identity_dsa(Buffer *b, DSA *key, const char *comment) int ssh_add_identity(AuthenticationConnection *auth, Key *key, const char *comment) { - Buffer buffer; + Buffer msg; int type; - buffer_init(&buffer); + buffer_init(&msg); switch (key->type) { - case KEY_RSA: - ssh_encode_identity_rsa(&buffer, key->rsa, comment); + case KEY_RSA1: + ssh_encode_identity_rsa1(&msg, key->rsa, comment); break; + case KEY_RSA: case KEY_DSA: - ssh_encode_identity_dsa(&buffer, key->dsa, comment); + ssh_encode_identity_ssh2(&msg, key, comment); break; default: - buffer_free(&buffer); + buffer_free(&msg); return 0; break; } - if (ssh_request_reply(auth, &buffer, &buffer) == 0) { - buffer_free(&buffer); + if (ssh_request_reply(auth, &msg, &msg) == 0) { + buffer_free(&msg); return 0; } - type = buffer_get_char(&buffer); - buffer_free(&buffer); + type = buffer_get_char(&msg); + buffer_free(&msg); return decode_reply(type); } @@ -390,23 +500,35 @@ ssh_add_identity(AuthenticationConnection *auth, Key *key, const char *comment) */ int -ssh_remove_identity(AuthenticationConnection *auth, RSA *key) +ssh_remove_identity(AuthenticationConnection *auth, Key *key) { - Buffer buffer; + Buffer msg; int type; - - buffer_init(&buffer); - buffer_put_char(&buffer, SSH_AGENTC_REMOVE_RSA_IDENTITY); - buffer_put_int(&buffer, BN_num_bits(key->n)); - buffer_put_bignum(&buffer, key->e); - buffer_put_bignum(&buffer, key->n); - - if (ssh_request_reply(auth, &buffer, &buffer) == 0) { - buffer_free(&buffer); + u_char *blob; + u_int blen; + + buffer_init(&msg); + + if (key->type == KEY_RSA1) { + buffer_put_char(&msg, SSH_AGENTC_REMOVE_RSA_IDENTITY); + buffer_put_int(&msg, BN_num_bits(key->rsa->n)); + buffer_put_bignum(&msg, key->rsa->e); + buffer_put_bignum(&msg, key->rsa->n); + } else if (key->type == KEY_DSA || key->type == KEY_RSA) { + key_to_blob(key, &blob, &blen); + buffer_put_char(&msg, SSH2_AGENTC_REMOVE_IDENTITY); + buffer_put_string(&msg, blob, blen); + xfree(blob); + } else { + buffer_free(&msg); return 0; } - type = buffer_get_char(&buffer); - buffer_free(&buffer); + if (ssh_request_reply(auth, &msg, &msg) == 0) { + buffer_free(&msg); + return 0; + } + type = buffer_get_char(&msg); + buffer_free(&msg); return decode_reply(type); } @@ -416,20 +538,23 @@ ssh_remove_identity(AuthenticationConnection *auth, RSA *key) */ int -ssh_remove_all_identities(AuthenticationConnection *auth) +ssh_remove_all_identities(AuthenticationConnection *auth, int version) { - Buffer buffer; + Buffer msg; int type; + int code = (version==1) ? + SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES : + SSH2_AGENTC_REMOVE_ALL_IDENTITIES; - buffer_init(&buffer); - buffer_put_char(&buffer, SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES); + buffer_init(&msg); + buffer_put_char(&msg, code); - if (ssh_request_reply(auth, &buffer, &buffer) == 0) { - buffer_free(&buffer); + if (ssh_request_reply(auth, &msg, &msg) == 0) { + buffer_free(&msg); return 0; } - type = buffer_get_char(&buffer); - buffer_free(&buffer); + type = buffer_get_char(&msg); + buffer_free(&msg); return decode_reply(type); } @@ -438,6 +563,7 @@ decode_reply(int type) { switch (type) { case SSH_AGENT_FAILURE: + case SSH_COM_AGENT2_FAILURE: log("SSH_AGENT_FAILURE"); return 0; case SSH_AGENT_SUCCESS: