1/* $NetBSD: authfd.c,v 1.27 2023/12/20 17:15:20 christos Exp $ */ 2/* $OpenBSD: authfd.c,v 1.134 2023/12/18 14:46:56 djm Exp $ */ 3 4/* 5 * Author: Tatu Ylonen <ylo@cs.hut.fi> 6 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 7 * All rights reserved 8 * Functions for connecting the local authentication agent. 9 * 10 * As far as I am concerned, the code I have written for this software 11 * can be used freely for any purpose. Any derived versions of this 12 * software must be clearly marked as such, and if the derived work is 13 * incompatible with the protocol description in the RFC file, it must be 14 * called by a name other than "ssh" or "Secure Shell". 15 * 16 * SSH2 implementation, 17 * Copyright (c) 2000 Markus Friedl. All rights reserved. 18 * 19 * Redistribution and use in source and binary forms, with or without 20 * modification, are permitted provided that the following conditions 21 * are met: 22 * 1. Redistributions of source code must retain the above copyright 23 * notice, this list of conditions and the following disclaimer. 24 * 2. Redistributions in binary form must reproduce the above copyright 25 * notice, this list of conditions and the following disclaimer in the 26 * documentation and/or other materials provided with the distribution. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 29 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 30 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 31 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 33 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 37 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40#include "includes.h" 41__RCSID("$NetBSD: authfd.c,v 1.27 2023/12/20 17:15:20 christos Exp $"); 42#include <sys/types.h> 43#include <sys/un.h> 44#include <sys/socket.h> 45 46#include <fcntl.h> 47#include <stdlib.h> 48#include <signal.h> 49#include <string.h> 50#include <stdarg.h> 51#include <unistd.h> 52#include <errno.h> 53 54#include "xmalloc.h" 55#include "ssh.h" 56#include "sshbuf.h" 57#include "sshkey.h" 58#include "authfd.h" 59#include "cipher.h" 60#include "log.h" 61#include "atomicio.h" 62#include "misc.h" 63#include "ssherr.h" 64 65#define MAX_AGENT_IDENTITIES 2048 /* Max keys in agent reply */ 66#define MAX_AGENT_REPLY_LEN (256 * 1024) /* Max bytes in agent reply */ 67 68/* macro to check for "agent failure" message */ 69#define agent_failed(x) \ 70 ((x == SSH_AGENT_FAILURE) || \ 71 (x == SSH_COM_AGENT2_FAILURE) || \ 72 (x == SSH2_AGENT_FAILURE)) 73 74/* Convert success/failure response from agent to a err.h status */ 75static int 76decode_reply(u_char type) 77{ 78 if (agent_failed(type)) 79 return SSH_ERR_AGENT_FAILURE; 80 else if (type == SSH_AGENT_SUCCESS) 81 return 0; 82 else 83 return SSH_ERR_INVALID_FORMAT; 84} 85 86/* 87 * Opens an authentication socket at the provided path and stores the file 88 * descriptor in fdp. Returns 0 on success and an error on failure. 89 */ 90int 91ssh_get_authentication_socket_path(const char *authsocket, int *fdp) 92{ 93 int sock, oerrno; 94 struct sockaddr_un sunaddr; 95 96 debug3_f("path '%s'", authsocket); 97 memset(&sunaddr, 0, sizeof(sunaddr)); 98 sunaddr.sun_family = AF_UNIX; 99 strlcpy(sunaddr.sun_path, authsocket, sizeof(sunaddr.sun_path)); 100 101 if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) 102 return SSH_ERR_SYSTEM_ERROR; 103 104 /* close on exec */ 105 if (fcntl(sock, F_SETFD, FD_CLOEXEC) == -1 || 106 connect(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) == -1) { 107 oerrno = errno; 108 close(sock); 109 errno = oerrno; 110 return SSH_ERR_SYSTEM_ERROR; 111 } 112 if (fdp != NULL) 113 *fdp = sock; 114 else 115 close(sock); 116 return 0; 117} 118 119/* 120 * Opens the default authentication socket and stores the file descriptor in 121 * fdp. Returns 0 on success and an error on failure. 122 */ 123int 124ssh_get_authentication_socket(int *fdp) 125{ 126 const char *authsocket; 127 128 if (fdp != NULL) 129 *fdp = -1; 130 131 authsocket = getenv(SSH_AUTHSOCKET_ENV_NAME); 132 if (authsocket == NULL || *authsocket == '\0') 133 return SSH_ERR_AGENT_NOT_PRESENT; 134 135 return ssh_get_authentication_socket_path(authsocket, fdp); 136} 137 138/* Communicate with agent: send request and read reply */ 139static int 140ssh_request_reply(int sock, struct sshbuf *request, struct sshbuf *reply) 141{ 142 int r; 143 size_t l, len; 144 char buf[1024]; 145 146 /* Get the length of the message, and format it in the buffer. */ 147 len = sshbuf_len(request); 148 POKE_U32(buf, len); 149 150 /* Send the length and then the packet to the agent. */ 151 if (atomicio(vwrite, sock, buf, 4) != 4 || 152 atomicio(vwrite, sock, sshbuf_mutable_ptr(request), 153 sshbuf_len(request)) != sshbuf_len(request)) 154 return SSH_ERR_AGENT_COMMUNICATION; 155 /* 156 * Wait for response from the agent. First read the length of the 157 * response packet. 158 */ 159 if (atomicio(read, sock, buf, 4) != 4) 160 return SSH_ERR_AGENT_COMMUNICATION; 161 162 /* Extract the length, and check it for sanity. */ 163 len = PEEK_U32(buf); 164 if (len > MAX_AGENT_REPLY_LEN) 165 return SSH_ERR_INVALID_FORMAT; 166 167 /* Read the rest of the response in to the buffer. */ 168 sshbuf_reset(reply); 169 while (len > 0) { 170 l = len; 171 if (l > sizeof(buf)) 172 l = sizeof(buf); 173 if (atomicio(read, sock, buf, l) != l) 174 return SSH_ERR_AGENT_COMMUNICATION; 175 if ((r = sshbuf_put(reply, buf, l)) != 0) 176 return r; 177 len -= l; 178 } 179 return 0; 180} 181 182/* Communicate with agent: sent request, read and decode status reply */ 183static int 184ssh_request_reply_decode(int sock, struct sshbuf *request) 185{ 186 struct sshbuf *reply; 187 int r; 188 u_char type; 189 190 if ((reply = sshbuf_new()) == NULL) 191 return SSH_ERR_ALLOC_FAIL; 192 if ((r = ssh_request_reply(sock, request, reply)) != 0 || 193 (r = sshbuf_get_u8(reply, &type)) != 0 || 194 (r = decode_reply(type)) != 0) 195 goto out; 196 /* success */ 197 r = 0; 198 out: 199 sshbuf_free(reply); 200 return r; 201} 202 203/* 204 * Closes the agent socket if it should be closed (depends on how it was 205 * obtained). The argument must have been returned by 206 * ssh_get_authentication_socket(). 207 */ 208void 209ssh_close_authentication_socket(int sock) 210{ 211 if (getenv(SSH_AUTHSOCKET_ENV_NAME)) 212 close(sock); 213} 214 215/* Lock/unlock agent */ 216int 217ssh_lock_agent(int sock, int lock, const char *password) 218{ 219 int r; 220 u_char type = lock ? SSH_AGENTC_LOCK : SSH_AGENTC_UNLOCK; 221 struct sshbuf *msg; 222 223 if ((msg = sshbuf_new()) == NULL) 224 return SSH_ERR_ALLOC_FAIL; 225 if ((r = sshbuf_put_u8(msg, type)) != 0 || 226 (r = sshbuf_put_cstring(msg, password)) != 0 || 227 (r = ssh_request_reply_decode(sock, msg)) != 0) 228 goto out; 229 /* success */ 230 r = 0; 231 out: 232 sshbuf_free(msg); 233 return r; 234} 235 236 237static int 238deserialise_identity2(struct sshbuf *ids, struct sshkey **keyp, char **commentp) 239{ 240 int r; 241 char *comment = NULL; 242 const u_char *blob; 243 size_t blen; 244 245 if ((r = sshbuf_get_string_direct(ids, &blob, &blen)) != 0 || 246 (r = sshbuf_get_cstring(ids, &comment, NULL)) != 0) 247 goto out; 248 if ((r = sshkey_from_blob(blob, blen, keyp)) != 0) 249 goto out; 250 if (commentp != NULL) { 251 *commentp = comment; 252 comment = NULL; 253 } 254 r = 0; 255 out: 256 free(comment); 257 return r; 258} 259 260/* 261 * Fetch list of identities held by the agent. 262 */ 263int 264ssh_fetch_identitylist(int sock, struct ssh_identitylist **idlp) 265{ 266 u_char type; 267 u_int32_t num, i; 268 struct sshbuf *msg; 269 struct ssh_identitylist *idl = NULL; 270 int r; 271 272 /* 273 * Send a message to the agent requesting for a list of the 274 * identities it can represent. 275 */ 276 if ((msg = sshbuf_new()) == NULL) 277 return SSH_ERR_ALLOC_FAIL; 278 if ((r = sshbuf_put_u8(msg, SSH2_AGENTC_REQUEST_IDENTITIES)) != 0) 279 goto out; 280 281 if ((r = ssh_request_reply(sock, msg, msg)) != 0) 282 goto out; 283 284 /* Get message type, and verify that we got a proper answer. */ 285 if ((r = sshbuf_get_u8(msg, &type)) != 0) 286 goto out; 287 if (agent_failed(type)) { 288 r = SSH_ERR_AGENT_FAILURE; 289 goto out; 290 } else if (type != SSH2_AGENT_IDENTITIES_ANSWER) { 291 r = SSH_ERR_INVALID_FORMAT; 292 goto out; 293 } 294 295 /* Get the number of entries in the response and check it for sanity. */ 296 if ((r = sshbuf_get_u32(msg, &num)) != 0) 297 goto out; 298 if (num > MAX_AGENT_IDENTITIES) { 299 r = SSH_ERR_INVALID_FORMAT; 300 goto out; 301 } 302 if (num == 0) { 303 r = SSH_ERR_AGENT_NO_IDENTITIES; 304 goto out; 305 } 306 307 /* Deserialise the response into a list of keys/comments */ 308 if ((idl = calloc(1, sizeof(*idl))) == NULL || 309 (idl->keys = calloc(num, sizeof(*idl->keys))) == NULL || 310 (idl->comments = calloc(num, sizeof(*idl->comments))) == NULL) { 311 r = SSH_ERR_ALLOC_FAIL; 312 goto out; 313 } 314 for (i = 0; i < num;) { 315 if ((r = deserialise_identity2(msg, &(idl->keys[i]), 316 &(idl->comments[i]))) != 0) { 317 if (r == SSH_ERR_KEY_TYPE_UNKNOWN) { 318 /* Gracefully skip unknown key types */ 319 num--; 320 continue; 321 } else 322 goto out; 323 } 324 i++; 325 } 326 idl->nkeys = num; 327 *idlp = idl; 328 idl = NULL; 329 r = 0; 330 out: 331 sshbuf_free(msg); 332 if (idl != NULL) 333 ssh_free_identitylist(idl); 334 return r; 335} 336 337void 338ssh_free_identitylist(struct ssh_identitylist *idl) 339{ 340 size_t i; 341 342 if (idl == NULL) 343 return; 344 for (i = 0; i < idl->nkeys; i++) { 345 if (idl->keys != NULL) 346 sshkey_free(idl->keys[i]); 347 if (idl->comments != NULL) 348 free(idl->comments[i]); 349 } 350 free(idl->keys); 351 free(idl->comments); 352 free(idl); 353} 354 355/* 356 * Check if the ssh agent has a given key. 357 * Returns 0 if found, or a negative SSH_ERR_* error code on failure. 358 */ 359int 360ssh_agent_has_key(int sock, const struct sshkey *key) 361{ 362 int r, ret = SSH_ERR_KEY_NOT_FOUND; 363 size_t i; 364 struct ssh_identitylist *idlist = NULL; 365 366 if ((r = ssh_fetch_identitylist(sock, &idlist)) != 0) { 367 return r; 368 } 369 370 for (i = 0; i < idlist->nkeys; i++) { 371 if (sshkey_equal_public(idlist->keys[i], key)) { 372 ret = 0; 373 break; 374 } 375 } 376 377 ssh_free_identitylist(idlist); 378 return ret; 379} 380 381/* 382 * Sends a challenge (typically from a server via ssh(1)) to the agent, 383 * and waits for a response from the agent. 384 * Returns true (non-zero) if the agent gave the correct answer, zero 385 * otherwise. 386 */ 387 388 389/* encode signature algorithm in flag bits, so we can keep the msg format */ 390static u_int 391agent_encode_alg(const struct sshkey *key, const char *alg) 392{ 393 if (alg != NULL && sshkey_type_plain(key->type) == KEY_RSA) { 394 if (strcmp(alg, "rsa-sha2-256") == 0 || 395 strcmp(alg, "rsa-sha2-256-cert-v01@openssh.com") == 0) 396 return SSH_AGENT_RSA_SHA2_256; 397 if (strcmp(alg, "rsa-sha2-512") == 0 || 398 strcmp(alg, "rsa-sha2-512-cert-v01@openssh.com") == 0) 399 return SSH_AGENT_RSA_SHA2_512; 400 } 401 return 0; 402} 403 404/* ask agent to sign data, returns err.h code on error, 0 on success */ 405int 406ssh_agent_sign(int sock, const struct sshkey *key, 407 u_char **sigp, size_t *lenp, 408 const u_char *data, size_t datalen, const char *alg, u_int compat) 409{ 410 struct sshbuf *msg; 411 u_char *sig = NULL, type = 0; 412 size_t len = 0; 413 u_int flags = 0; 414 int r = SSH_ERR_INTERNAL_ERROR; 415 416 *sigp = NULL; 417 *lenp = 0; 418 419 if (datalen > SSH_KEY_MAX_SIGN_DATA_SIZE) 420 return SSH_ERR_INVALID_ARGUMENT; 421 if ((msg = sshbuf_new()) == NULL) 422 return SSH_ERR_ALLOC_FAIL; 423 flags |= agent_encode_alg(key, alg); 424 if ((r = sshbuf_put_u8(msg, SSH2_AGENTC_SIGN_REQUEST)) != 0 || 425 (r = sshkey_puts(key, msg)) != 0 || 426 (r = sshbuf_put_string(msg, data, datalen)) != 0 || 427 (r = sshbuf_put_u32(msg, flags)) != 0) 428 goto out; 429 if ((r = ssh_request_reply(sock, msg, msg)) != 0) 430 goto out; 431 if ((r = sshbuf_get_u8(msg, &type)) != 0) 432 goto out; 433 if (agent_failed(type)) { 434 r = SSH_ERR_AGENT_FAILURE; 435 goto out; 436 } else if (type != SSH2_AGENT_SIGN_RESPONSE) { 437 r = SSH_ERR_INVALID_FORMAT; 438 goto out; 439 } 440 if ((r = sshbuf_get_string(msg, &sig, &len)) != 0) 441 goto out; 442 /* Check what we actually got back from the agent. */ 443 if ((r = sshkey_check_sigtype(sig, len, alg)) != 0) 444 goto out; 445 /* success */ 446 *sigp = sig; 447 *lenp = len; 448 sig = NULL; 449 len = 0; 450 r = 0; 451 out: 452 freezero(sig, len); 453 sshbuf_free(msg); 454 return r; 455} 456 457/* Encode key for a message to the agent. */ 458 459static int 460encode_dest_constraint_hop(struct sshbuf *m, 461 const struct dest_constraint_hop *dch) 462{ 463 struct sshbuf *b; 464 u_int i; 465 int r; 466 467 if ((b = sshbuf_new()) == NULL) 468 return SSH_ERR_ALLOC_FAIL; 469 if ((r = sshbuf_put_cstring(b, dch->user)) != 0 || 470 (r = sshbuf_put_cstring(b, dch->hostname)) != 0 || 471 (r = sshbuf_put_string(b, NULL, 0)) != 0) /* reserved */ 472 goto out; 473 for (i = 0; i < dch->nkeys; i++) { 474 if ((r = sshkey_puts(dch->keys[i], b)) != 0 || 475 (r = sshbuf_put_u8(b, dch->key_is_ca[i] != 0)) != 0) 476 goto out; 477 } 478 if ((r = sshbuf_put_stringb(m, b)) != 0) 479 goto out; 480 /* success */ 481 r = 0; 482 out: 483 sshbuf_free(b); 484 return r; 485} 486 487static int 488encode_dest_constraint(struct sshbuf *m, const struct dest_constraint *dc) 489{ 490 struct sshbuf *b; 491 int r; 492 493 if ((b = sshbuf_new()) == NULL) 494 return SSH_ERR_ALLOC_FAIL; 495 if ((r = encode_dest_constraint_hop(b, &dc->from)) != 0 || 496 (r = encode_dest_constraint_hop(b, &dc->to)) != 0 || 497 (r = sshbuf_put_string(b, NULL, 0)) != 0) /* reserved */ 498 goto out; 499 if ((r = sshbuf_put_stringb(m, b)) != 0) 500 goto out; 501 /* success */ 502 r = 0; 503 out: 504 sshbuf_free(b); 505 return r; 506} 507 508static int 509encode_constraints(struct sshbuf *m, u_int life, u_int confirm, 510 u_int maxsign, const char *provider, 511 struct dest_constraint **dest_constraints, size_t ndest_constraints, 512 int cert_only, struct sshkey **certs, size_t ncerts) 513{ 514 int r; 515 struct sshbuf *b = NULL; 516 size_t i; 517 518 if (life != 0) { 519 if ((r = sshbuf_put_u8(m, SSH_AGENT_CONSTRAIN_LIFETIME)) != 0 || 520 (r = sshbuf_put_u32(m, life)) != 0) 521 goto out; 522 } 523 if (confirm != 0) { 524 if ((r = sshbuf_put_u8(m, SSH_AGENT_CONSTRAIN_CONFIRM)) != 0) 525 goto out; 526 } 527 if (maxsign != 0) { 528 if ((r = sshbuf_put_u8(m, SSH_AGENT_CONSTRAIN_MAXSIGN)) != 0 || 529 (r = sshbuf_put_u32(m, maxsign)) != 0) 530 goto out; 531 } 532 if (provider != NULL) { 533 if ((r = sshbuf_put_u8(m, 534 SSH_AGENT_CONSTRAIN_EXTENSION)) != 0 || 535 (r = sshbuf_put_cstring(m, 536 "sk-provider@openssh.com")) != 0 || 537 (r = sshbuf_put_cstring(m, provider)) != 0) 538 goto out; 539 } 540 if (dest_constraints != NULL && ndest_constraints > 0) { 541 if ((b = sshbuf_new()) == NULL) { 542 r = SSH_ERR_ALLOC_FAIL; 543 goto out; 544 } 545 for (i = 0; i < ndest_constraints; i++) { 546 if ((r = encode_dest_constraint(b, 547 dest_constraints[i])) != 0) 548 goto out; 549 } 550 if ((r = sshbuf_put_u8(m, 551 SSH_AGENT_CONSTRAIN_EXTENSION)) != 0 || 552 (r = sshbuf_put_cstring(m, 553 "restrict-destination-v00@openssh.com")) != 0 || 554 (r = sshbuf_put_stringb(m, b)) != 0) 555 goto out; 556 sshbuf_free(b); 557 b = NULL; 558 } 559 if (ncerts != 0) { 560 if ((b = sshbuf_new()) == NULL) { 561 r = SSH_ERR_ALLOC_FAIL; 562 goto out; 563 } 564 for (i = 0; i < ncerts; i++) { 565 if ((r = sshkey_puts(certs[i], b)) != 0) 566 goto out; 567 } 568 if ((r = sshbuf_put_u8(m, 569 SSH_AGENT_CONSTRAIN_EXTENSION)) != 0 || 570 (r = sshbuf_put_cstring(m, 571 "associated-certs-v00@openssh.com")) != 0 || 572 (r = sshbuf_put_u8(m, cert_only != 0)) != 0 || 573 (r = sshbuf_put_stringb(m, b)) != 0) 574 goto out; 575 sshbuf_free(b); 576 b = NULL; 577 } 578 r = 0; 579 out: 580 sshbuf_free(b); 581 return r; 582} 583 584/* 585 * Adds an identity to the authentication server. 586 * This call is intended only for use by ssh-add(1) and like applications. 587 */ 588int 589ssh_add_identity_constrained(int sock, struct sshkey *key, 590 const char *comment, u_int life, u_int confirm, u_int maxsign, 591 const char *provider, struct dest_constraint **dest_constraints, 592 size_t ndest_constraints) 593{ 594 struct sshbuf *msg; 595 int r, constrained = (life || confirm || maxsign || 596 provider || dest_constraints); 597 u_char type; 598 599 if ((msg = sshbuf_new()) == NULL) 600 return SSH_ERR_ALLOC_FAIL; 601 602 switch (key->type) { 603#ifdef WITH_OPENSSL 604 case KEY_RSA: 605 case KEY_RSA_CERT: 606 case KEY_DSA: 607 case KEY_DSA_CERT: 608 case KEY_ECDSA: 609 case KEY_ECDSA_CERT: 610 case KEY_ECDSA_SK: 611 case KEY_ECDSA_SK_CERT: 612#endif 613 case KEY_ED25519: 614 case KEY_ED25519_CERT: 615 case KEY_ED25519_SK: 616 case KEY_ED25519_SK_CERT: 617 case KEY_XMSS: 618 case KEY_XMSS_CERT: 619 type = constrained ? 620 SSH2_AGENTC_ADD_ID_CONSTRAINED : 621 SSH2_AGENTC_ADD_IDENTITY; 622 if ((r = sshbuf_put_u8(msg, type)) != 0 || 623 (r = sshkey_private_serialize_maxsign(key, msg, maxsign, 624 0)) != 0 || 625 (r = sshbuf_put_cstring(msg, comment)) != 0) 626 goto out; 627 break; 628 default: 629 r = SSH_ERR_INVALID_ARGUMENT; 630 goto out; 631 } 632 if (constrained && 633 (r = encode_constraints(msg, life, confirm, maxsign, 634 provider, dest_constraints, ndest_constraints, 0, NULL, 0)) != 0) 635 goto out; 636 if ((r = ssh_request_reply_decode(sock, msg)) != 0) 637 goto out; 638 /* success */ 639 r = 0; 640 out: 641 sshbuf_free(msg); 642 return r; 643} 644 645/* 646 * Removes an identity from the authentication server. 647 * This call is intended only for use by ssh-add(1) and like applications. 648 */ 649int 650ssh_remove_identity(int sock, const struct sshkey *key) 651{ 652 struct sshbuf *msg; 653 int r; 654 u_char *blob = NULL; 655 size_t blen; 656 657 if ((msg = sshbuf_new()) == NULL) 658 return SSH_ERR_ALLOC_FAIL; 659 660 if (key->type != KEY_UNSPEC) { 661 if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) 662 goto out; 663 if ((r = sshbuf_put_u8(msg, 664 SSH2_AGENTC_REMOVE_IDENTITY)) != 0 || 665 (r = sshbuf_put_string(msg, blob, blen)) != 0) 666 goto out; 667 } else { 668 r = SSH_ERR_INVALID_ARGUMENT; 669 goto out; 670 } 671 if ((r = ssh_request_reply_decode(sock, msg)) != 0) 672 goto out; 673 /* success */ 674 r = 0; 675 out: 676 if (blob != NULL) 677 freezero(blob, blen); 678 sshbuf_free(msg); 679 return r; 680} 681 682/* 683 * Add/remove an token-based identity from the authentication server. 684 * This call is intended only for use by ssh-add(1) and like applications. 685 */ 686int 687ssh_update_card(int sock, int add, const char *reader_id, const char *pin, 688 u_int life, u_int confirm, 689 struct dest_constraint **dest_constraints, size_t ndest_constraints, 690 int cert_only, struct sshkey **certs, size_t ncerts) 691{ 692 struct sshbuf *msg; 693 int r, constrained = (life || confirm || dest_constraints || certs); 694 u_char type; 695 696 if (add) { 697 type = constrained ? 698 SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED : 699 SSH_AGENTC_ADD_SMARTCARD_KEY; 700 } else 701 type = SSH_AGENTC_REMOVE_SMARTCARD_KEY; 702 703 if ((msg = sshbuf_new()) == NULL) 704 return SSH_ERR_ALLOC_FAIL; 705 if ((r = sshbuf_put_u8(msg, type)) != 0 || 706 (r = sshbuf_put_cstring(msg, reader_id)) != 0 || 707 (r = sshbuf_put_cstring(msg, pin)) != 0) 708 goto out; 709 if (constrained && 710 (r = encode_constraints(msg, life, confirm, 0, NULL, 711 dest_constraints, ndest_constraints, 712 cert_only, certs, ncerts)) != 0) 713 goto out; 714 if ((r = ssh_request_reply_decode(sock, msg)) != 0) 715 goto out; 716 /* success */ 717 r = 0; 718 out: 719 sshbuf_free(msg); 720 return r; 721} 722 723/* 724 * Removes all identities from the agent. 725 * This call is intended only for use by ssh-add(1) and like applications. 726 * 727 * This supports the SSH protocol 1 message to because, when clearing all 728 * keys from an agent, we generally want to clear both protocol v1 and v2 729 * keys. 730 */ 731int 732ssh_remove_all_identities(int sock, int version) 733{ 734 struct sshbuf *msg; 735 u_char type = (version == 1) ? 736 SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES : 737 SSH2_AGENTC_REMOVE_ALL_IDENTITIES; 738 int r; 739 740 if ((msg = sshbuf_new()) == NULL) 741 return SSH_ERR_ALLOC_FAIL; 742 if ((r = sshbuf_put_u8(msg, type)) != 0) 743 goto out; 744 if ((r = ssh_request_reply_decode(sock, msg)) != 0) 745 goto out; 746 /* success */ 747 r = 0; 748 out: 749 sshbuf_free(msg); 750 return r; 751} 752 753/* Binds a session ID to a hostkey via the initial KEX signature. */ 754int 755ssh_agent_bind_hostkey(int sock, const struct sshkey *key, 756 const struct sshbuf *session_id, const struct sshbuf *signature, 757 int forwarding) 758{ 759 struct sshbuf *msg; 760 int r; 761 762 if (key == NULL || session_id == NULL || signature == NULL) 763 return SSH_ERR_INVALID_ARGUMENT; 764 if ((msg = sshbuf_new()) == NULL) 765 return SSH_ERR_ALLOC_FAIL; 766 if ((r = sshbuf_put_u8(msg, SSH_AGENTC_EXTENSION)) != 0 || 767 (r = sshbuf_put_cstring(msg, "session-bind@openssh.com")) != 0 || 768 (r = sshkey_puts(key, msg)) != 0 || 769 (r = sshbuf_put_stringb(msg, session_id)) != 0 || 770 (r = sshbuf_put_stringb(msg, signature)) != 0 || 771 (r = sshbuf_put_u8(msg, forwarding ? 1 : 0)) != 0) 772 goto out; 773 if ((r = ssh_request_reply_decode(sock, msg)) != 0) 774 goto out; 775 /* success */ 776 r = 0; 777 out: 778 sshbuf_free(msg); 779 return r; 780} 781