| File: | src/usr.bin/ssh/ssh-sk-helper/../sk-usbhid.c |
| Warning: | line 1252, column 9 Although the value stored to 'r' is used in the enclosing expression, the value is never actually read from 'r' |
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| 1 | /* $OpenBSD: sk-usbhid.c,v 1.46 2023/03/28 06:12:38 dtucker Exp $ */ |
| 2 | /* |
| 3 | * Copyright (c) 2019 Markus Friedl |
| 4 | * Copyright (c) 2020 Pedro Martelletto |
| 5 | * |
| 6 | * Permission to use, copy, modify, and distribute this software for any |
| 7 | * purpose with or without fee is hereby granted, provided that the above |
| 8 | * copyright notice and this permission notice appear in all copies. |
| 9 | * |
| 10 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| 11 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| 12 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| 13 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 14 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| 15 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
| 16 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 17 | */ |
| 18 | |
| 19 | #include <stdint.h> |
| 20 | #include <stdlib.h> |
| 21 | #include <string.h> |
| 22 | #include <stdio.h> |
| 23 | #include <stddef.h> |
| 24 | #include <stdarg.h> |
| 25 | #include <time.h> |
| 26 | |
| 27 | #ifdef WITH_OPENSSL1 |
| 28 | #include <openssl/opensslv.h> |
| 29 | #include <openssl/crypto.h> |
| 30 | #include <openssl/bn.h> |
| 31 | #include <openssl/ec.h> |
| 32 | #include <openssl/ecdsa.h> |
| 33 | #include <openssl/evp.h> |
| 34 | #endif /* WITH_OPENSSL */ |
| 35 | |
| 36 | #include <fido.h> |
| 37 | #include <fido/credman.h> |
| 38 | |
| 39 | #ifndef SK_STANDALONE |
| 40 | # include "log.h" |
| 41 | # include "xmalloc.h" |
| 42 | # include "misc.h" |
| 43 | /* |
| 44 | * If building as part of OpenSSH, then rename exported functions. |
| 45 | * This must be done before including sk-api.h. |
| 46 | */ |
| 47 | # define sk_api_versionssh_sk_api_version ssh_sk_api_version |
| 48 | # define sk_enrollssh_sk_enroll ssh_sk_enroll |
| 49 | # define sk_signssh_sk_sign ssh_sk_sign |
| 50 | # define sk_load_resident_keysssh_sk_load_resident_keys ssh_sk_load_resident_keys |
| 51 | #endif /* !SK_STANDALONE */ |
| 52 | |
| 53 | #include "sk-api.h" |
| 54 | |
| 55 | /* #define SK_DEBUG 1 */ |
| 56 | |
| 57 | #ifdef SK_DEBUG |
| 58 | #define SSH_FIDO_INIT_ARG0 FIDO_DEBUG0x01 |
| 59 | #else |
| 60 | #define SSH_FIDO_INIT_ARG0 0 |
| 61 | #endif |
| 62 | |
| 63 | #define MAX_FIDO_DEVICES8 8 |
| 64 | #define FIDO_POLL_MS50 50 |
| 65 | #define SELECT_MS15000 15000 |
| 66 | #define POLL_SLEEP_NS200000000 200000000 |
| 67 | |
| 68 | #ifndef FIDO_ERR_OPERATION_DENIED0x27 |
| 69 | #define FIDO_ERR_OPERATION_DENIED0x27 0x27 |
| 70 | #endif |
| 71 | |
| 72 | struct sk_usbhid { |
| 73 | fido_dev_t *dev; |
| 74 | char *path; |
| 75 | }; |
| 76 | |
| 77 | /* Return the version of the middleware API */ |
| 78 | uint32_t sk_api_versionssh_sk_api_version(void); |
| 79 | |
| 80 | /* Enroll a U2F key (private key generation) */ |
| 81 | int sk_enrollssh_sk_enroll(uint32_t alg, const uint8_t *challenge, size_t challenge_len, |
| 82 | const char *application, uint8_t flags, const char *pin, |
| 83 | struct sk_option **options, struct sk_enroll_response **enroll_response); |
| 84 | |
| 85 | /* Sign a challenge */ |
| 86 | int sk_signssh_sk_sign(uint32_t alg, const uint8_t *data, size_t data_len, |
| 87 | const char *application, const uint8_t *key_handle, size_t key_handle_len, |
| 88 | uint8_t flags, const char *pin, struct sk_option **options, |
| 89 | struct sk_sign_response **sign_response); |
| 90 | |
| 91 | /* Load resident keys */ |
| 92 | int sk_load_resident_keysssh_sk_load_resident_keys(const char *pin, struct sk_option **options, |
| 93 | struct sk_resident_key ***rks, size_t *nrks); |
| 94 | |
| 95 | static void skdebug(const char *func, const char *fmt, ...) |
| 96 | __attribute__((__format__ (printf, 2, 3))); |
| 97 | |
| 98 | static void |
| 99 | skdebug(const char *func, const char *fmt, ...) |
| 100 | { |
| 101 | #if !defined(SK_STANDALONE) |
| 102 | char *msg; |
| 103 | va_list ap; |
| 104 | |
| 105 | va_start(ap, fmt)__builtin_va_start((ap), fmt); |
| 106 | xvasprintf(&msg, fmt, ap); |
| 107 | va_end(ap)__builtin_va_end((ap)); |
| 108 | debug("%s: %s", func, msg)sshlog("/usr/src/usr.bin/ssh/ssh-sk-helper/../sk-usbhid.c", __func__ , 108, 0, SYSLOG_LEVEL_DEBUG1, ((void *)0), "%s: %s", func, msg ); |
| 109 | free(msg); |
| 110 | #elif defined(SK_DEBUG) |
| 111 | va_list ap; |
| 112 | |
| 113 | va_start(ap, fmt)__builtin_va_start((ap), fmt); |
| 114 | fprintf(stderr(&__sF[2]), "%s: ", func); |
| 115 | vfprintf(stderr(&__sF[2]), fmt, ap); |
| 116 | fputc('\n', stderr(&__sF[2])); |
| 117 | va_end(ap)__builtin_va_end((ap)); |
| 118 | #else |
| 119 | (void)func; /* XXX */ |
| 120 | (void)fmt; /* XXX */ |
| 121 | #endif |
| 122 | } |
| 123 | |
| 124 | uint32_t |
| 125 | sk_api_versionssh_sk_api_version(void) |
| 126 | { |
| 127 | return SSH_SK_VERSION_MAJOR0x000a0000; |
| 128 | } |
| 129 | |
| 130 | static struct sk_usbhid * |
| 131 | sk_open(const char *path) |
| 132 | { |
| 133 | struct sk_usbhid *sk; |
| 134 | int r; |
| 135 | |
| 136 | if (path == NULL((void *)0)) { |
| 137 | skdebug(__func__, "path == NULL"); |
| 138 | return NULL((void *)0); |
| 139 | } |
| 140 | if ((sk = calloc(1, sizeof(*sk))) == NULL((void *)0)) { |
| 141 | skdebug(__func__, "calloc sk failed"); |
| 142 | return NULL((void *)0); |
| 143 | } |
| 144 | if ((sk->path = strdup(path)) == NULL((void *)0)) { |
| 145 | skdebug(__func__, "strdup path failed"); |
| 146 | free(sk); |
| 147 | return NULL((void *)0); |
| 148 | } |
| 149 | if ((sk->dev = fido_dev_new()) == NULL((void *)0)) { |
| 150 | skdebug(__func__, "fido_dev_new failed"); |
| 151 | free(sk->path); |
| 152 | free(sk); |
| 153 | return NULL((void *)0); |
| 154 | } |
| 155 | if ((r = fido_dev_open(sk->dev, sk->path)) != FIDO_OK0x00) { |
| 156 | skdebug(__func__, "fido_dev_open %s failed: %s", sk->path, |
| 157 | fido_strerr(r)); |
| 158 | fido_dev_free(&sk->dev); |
| 159 | free(sk->path); |
| 160 | free(sk); |
| 161 | return NULL((void *)0); |
| 162 | } |
| 163 | return sk; |
| 164 | } |
| 165 | |
| 166 | static void |
| 167 | sk_close(struct sk_usbhid *sk) |
| 168 | { |
| 169 | if (sk == NULL((void *)0)) |
| 170 | return; |
| 171 | fido_dev_cancel(sk->dev); /* cancel any pending operation */ |
| 172 | fido_dev_close(sk->dev); |
| 173 | fido_dev_free(&sk->dev); |
| 174 | free(sk->path); |
| 175 | free(sk); |
| 176 | } |
| 177 | |
| 178 | static struct sk_usbhid ** |
| 179 | sk_openv(const fido_dev_info_t *devlist, size_t ndevs, size_t *nopen) |
| 180 | { |
| 181 | const fido_dev_info_t *di; |
| 182 | struct sk_usbhid **skv; |
| 183 | size_t i; |
| 184 | |
| 185 | *nopen = 0; |
| 186 | if ((skv = calloc(ndevs, sizeof(*skv))) == NULL((void *)0)) { |
| 187 | skdebug(__func__, "calloc skv failed"); |
| 188 | return NULL((void *)0); |
| 189 | } |
| 190 | for (i = 0; i < ndevs; i++) { |
| 191 | if ((di = fido_dev_info_ptr(devlist, i)) == NULL((void *)0)) |
| 192 | skdebug(__func__, "fido_dev_info_ptr failed"); |
| 193 | else if ((skv[*nopen] = sk_open(fido_dev_info_path(di))) == NULL((void *)0)) |
| 194 | skdebug(__func__, "sk_open failed"); |
| 195 | else |
| 196 | (*nopen)++; |
| 197 | } |
| 198 | if (*nopen == 0) { |
| 199 | for (i = 0; i < ndevs; i++) |
| 200 | sk_close(skv[i]); |
| 201 | free(skv); |
| 202 | skv = NULL((void *)0); |
| 203 | } |
| 204 | |
| 205 | return skv; |
| 206 | } |
| 207 | |
| 208 | static void |
| 209 | sk_closev(struct sk_usbhid **skv, size_t nsk) |
| 210 | { |
| 211 | size_t i; |
| 212 | |
| 213 | for (i = 0; i < nsk; i++) |
| 214 | sk_close(skv[i]); |
| 215 | free(skv); |
| 216 | } |
| 217 | |
| 218 | static int |
| 219 | sk_touch_begin(struct sk_usbhid **skv, size_t nsk) |
| 220 | { |
| 221 | size_t i, ok = 0; |
| 222 | int r; |
| 223 | |
| 224 | for (i = 0; i < nsk; i++) |
| 225 | if ((r = fido_dev_get_touch_begin(skv[i]->dev)) != FIDO_OK0x00) |
| 226 | skdebug(__func__, "fido_dev_get_touch_begin %s failed:" |
| 227 | " %s", skv[i]->path, fido_strerr(r)); |
| 228 | else |
| 229 | ok++; |
| 230 | |
| 231 | return ok ? 0 : -1; |
| 232 | } |
| 233 | |
| 234 | static int |
| 235 | sk_touch_poll(struct sk_usbhid **skv, size_t nsk, int *touch, size_t *idx) |
| 236 | { |
| 237 | struct timespec ts_pause; |
| 238 | size_t npoll, i; |
| 239 | int r; |
| 240 | |
| 241 | ts_pause.tv_sec = 0; |
| 242 | ts_pause.tv_nsec = POLL_SLEEP_NS200000000; |
| 243 | nanosleep(&ts_pause, NULL((void *)0)); |
| 244 | npoll = nsk; |
| 245 | for (i = 0; i < nsk; i++) { |
| 246 | if (skv[i] == NULL((void *)0)) |
| 247 | continue; /* device discarded */ |
| 248 | skdebug(__func__, "polling %s", skv[i]->path); |
| 249 | if ((r = fido_dev_get_touch_status(skv[i]->dev, touch, |
| 250 | FIDO_POLL_MS50)) != FIDO_OK0x00) { |
| 251 | skdebug(__func__, "fido_dev_get_touch_status %s: %s", |
| 252 | skv[i]->path, fido_strerr(r)); |
| 253 | sk_close(skv[i]); /* discard device */ |
| 254 | skv[i] = NULL((void *)0); |
| 255 | if (--npoll == 0) { |
| 256 | skdebug(__func__, "no device left to poll"); |
| 257 | return -1; |
| 258 | } |
| 259 | } else if (*touch) { |
| 260 | *idx = i; |
| 261 | return 0; |
| 262 | } |
| 263 | } |
| 264 | *touch = 0; |
| 265 | return 0; |
| 266 | } |
| 267 | |
| 268 | /* Check if the specified key handle exists on a given sk. */ |
| 269 | static int |
| 270 | sk_try(const struct sk_usbhid *sk, const char *application, |
| 271 | const uint8_t *key_handle, size_t key_handle_len) |
| 272 | { |
| 273 | fido_assert_t *assert = NULL((void *)0); |
| 274 | int r = FIDO_ERR_INTERNAL-9; |
| 275 | uint8_t message[32]; |
| 276 | |
| 277 | memset(message, '\0', sizeof(message)); |
| 278 | if ((assert = fido_assert_new()) == NULL((void *)0)) { |
| 279 | skdebug(__func__, "fido_assert_new failed"); |
| 280 | goto out; |
| 281 | } |
| 282 | /* generate an invalid signature on FIDO2 tokens */ |
| 283 | if ((r = fido_assert_set_clientdata(assert, message, |
| 284 | sizeof(message))) != FIDO_OK0x00) { |
| 285 | skdebug(__func__, "fido_assert_set_clientdata: %s", |
| 286 | fido_strerr(r)); |
| 287 | goto out; |
| 288 | } |
| 289 | if ((r = fido_assert_set_rp(assert, application)) != FIDO_OK0x00) { |
| 290 | skdebug(__func__, "fido_assert_set_rp: %s", fido_strerr(r)); |
| 291 | goto out; |
| 292 | } |
| 293 | if ((r = fido_assert_allow_cred(assert, key_handle, |
| 294 | key_handle_len)) != FIDO_OK0x00) { |
| 295 | skdebug(__func__, "fido_assert_allow_cred: %s", fido_strerr(r)); |
| 296 | goto out; |
| 297 | } |
| 298 | if ((r = fido_assert_set_up(assert, FIDO_OPT_FALSE)) != FIDO_OK0x00) { |
| 299 | skdebug(__func__, "fido_assert_up: %s", fido_strerr(r)); |
| 300 | goto out; |
| 301 | } |
| 302 | r = fido_dev_get_assert(sk->dev, assert, NULL((void *)0)); |
| 303 | skdebug(__func__, "fido_dev_get_assert: %s", fido_strerr(r)); |
| 304 | if (r == FIDO_ERR_USER_PRESENCE_REQUIRED-8) { |
| 305 | /* U2F tokens may return this */ |
| 306 | r = FIDO_OK0x00; |
| 307 | } |
| 308 | out: |
| 309 | fido_assert_free(&assert); |
| 310 | |
| 311 | return r != FIDO_OK0x00 ? -1 : 0; |
| 312 | } |
| 313 | |
| 314 | static int |
| 315 | check_sk_options(fido_dev_t *dev, const char *opt, int *ret) |
| 316 | { |
| 317 | fido_cbor_info_t *info; |
| 318 | char * const *name; |
| 319 | const bool_Bool *value; |
| 320 | size_t len, i; |
| 321 | int r; |
| 322 | |
| 323 | *ret = -1; |
| 324 | |
| 325 | if (!fido_dev_is_fido2(dev)) { |
| 326 | skdebug(__func__, "device is not fido2"); |
| 327 | return 0; |
| 328 | } |
| 329 | if ((info = fido_cbor_info_new()) == NULL((void *)0)) { |
| 330 | skdebug(__func__, "fido_cbor_info_new failed"); |
| 331 | return -1; |
| 332 | } |
| 333 | if ((r = fido_dev_get_cbor_info(dev, info)) != FIDO_OK0x00) { |
| 334 | skdebug(__func__, "fido_dev_get_cbor_info: %s", fido_strerr(r)); |
| 335 | fido_cbor_info_free(&info); |
| 336 | return -1; |
| 337 | } |
| 338 | name = fido_cbor_info_options_name_ptr(info); |
| 339 | value = fido_cbor_info_options_value_ptr(info); |
| 340 | len = fido_cbor_info_options_len(info); |
| 341 | for (i = 0; i < len; i++) { |
| 342 | if (!strcmp(name[i], opt)) { |
| 343 | *ret = value[i]; |
| 344 | break; |
| 345 | } |
| 346 | } |
| 347 | fido_cbor_info_free(&info); |
| 348 | if (*ret == -1) |
| 349 | skdebug(__func__, "option %s is unknown", opt); |
| 350 | else |
| 351 | skdebug(__func__, "option %s is %s", opt, *ret ? "on" : "off"); |
| 352 | |
| 353 | return 0; |
| 354 | } |
| 355 | |
| 356 | static struct sk_usbhid * |
| 357 | sk_select_by_cred(const fido_dev_info_t *devlist, size_t ndevs, |
| 358 | const char *application, const uint8_t *key_handle, size_t key_handle_len) |
| 359 | { |
| 360 | struct sk_usbhid **skv, *sk; |
| 361 | size_t skvcnt, i; |
| 362 | int internal_uv; |
| 363 | |
| 364 | if ((skv = sk_openv(devlist, ndevs, &skvcnt)) == NULL((void *)0)) { |
| 365 | skdebug(__func__, "sk_openv failed"); |
| 366 | return NULL((void *)0); |
| 367 | } |
| 368 | if (skvcnt == 1 && check_sk_options(skv[0]->dev, "uv", |
| 369 | &internal_uv) == 0 && internal_uv != -1) { |
| 370 | sk = skv[0]; |
| 371 | skv[0] = NULL((void *)0); |
| 372 | goto out; |
| 373 | } |
| 374 | sk = NULL((void *)0); |
| 375 | for (i = 0; i < skvcnt; i++) { |
| 376 | if (sk_try(skv[i], application, key_handle, |
| 377 | key_handle_len) == 0) { |
| 378 | sk = skv[i]; |
| 379 | skv[i] = NULL((void *)0); |
| 380 | skdebug(__func__, "found key in %s", sk->path); |
| 381 | break; |
| 382 | } |
| 383 | } |
| 384 | out: |
| 385 | sk_closev(skv, skvcnt); |
| 386 | return sk; |
| 387 | } |
| 388 | |
| 389 | static struct sk_usbhid * |
| 390 | sk_select_by_touch(const fido_dev_info_t *devlist, size_t ndevs) |
| 391 | { |
| 392 | struct sk_usbhid **skv, *sk; |
| 393 | struct timeval tv_start, tv_now, tv_delta; |
| 394 | size_t skvcnt, idx; |
| 395 | int touch, ms_remain; |
| 396 | |
| 397 | if ((skv = sk_openv(devlist, ndevs, &skvcnt)) == NULL((void *)0)) { |
| 398 | skdebug(__func__, "sk_openv failed"); |
| 399 | return NULL((void *)0); |
| 400 | } |
| 401 | sk = NULL((void *)0); |
| 402 | if (skvcnt < 2) { |
| 403 | if (skvcnt == 1) { |
| 404 | /* single candidate */ |
| 405 | sk = skv[0]; |
| 406 | skv[0] = NULL((void *)0); |
| 407 | } |
| 408 | goto out; |
| 409 | } |
| 410 | if (sk_touch_begin(skv, skvcnt) == -1) { |
| 411 | skdebug(__func__, "sk_touch_begin failed"); |
| 412 | goto out; |
| 413 | } |
| 414 | monotime_tv(&tv_start); |
| 415 | do { |
| 416 | if (sk_touch_poll(skv, skvcnt, &touch, &idx) == -1) { |
| 417 | skdebug(__func__, "sk_touch_poll failed"); |
| 418 | goto out; |
| 419 | } |
| 420 | if (touch) { |
| 421 | sk = skv[idx]; |
| 422 | skv[idx] = NULL((void *)0); |
| 423 | goto out; |
| 424 | } |
| 425 | monotime_tv(&tv_now); |
| 426 | timersub(&tv_now, &tv_start, &tv_delta)do { (&tv_delta)->tv_sec = (&tv_now)->tv_sec - ( &tv_start)->tv_sec; (&tv_delta)->tv_usec = (& tv_now)->tv_usec - (&tv_start)->tv_usec; if ((& tv_delta)->tv_usec < 0) { (&tv_delta)->tv_sec--; (&tv_delta)->tv_usec += 1000000; } } while (0); |
| 427 | ms_remain = SELECT_MS15000 - tv_delta.tv_sec * 1000 - |
| 428 | tv_delta.tv_usec / 1000; |
| 429 | } while (ms_remain >= FIDO_POLL_MS50); |
| 430 | skdebug(__func__, "timeout"); |
| 431 | out: |
| 432 | sk_closev(skv, skvcnt); |
| 433 | return sk; |
| 434 | } |
| 435 | |
| 436 | static struct sk_usbhid * |
| 437 | sk_probe(const char *application, const uint8_t *key_handle, |
| 438 | size_t key_handle_len, int probe_resident) |
| 439 | { |
| 440 | struct sk_usbhid *sk; |
| 441 | fido_dev_info_t *devlist; |
| 442 | size_t ndevs; |
| 443 | int r; |
| 444 | |
| 445 | if ((devlist = fido_dev_info_new(MAX_FIDO_DEVICES8)) == NULL((void *)0)) { |
| 446 | skdebug(__func__, "fido_dev_info_new failed"); |
| 447 | return NULL((void *)0); |
| 448 | } |
| 449 | if ((r = fido_dev_info_manifest(devlist, MAX_FIDO_DEVICES8, |
| 450 | &ndevs)) != FIDO_OK0x00) { |
| 451 | skdebug(__func__, "fido_dev_info_manifest failed: %s", |
| 452 | fido_strerr(r)); |
| 453 | fido_dev_info_free(&devlist, MAX_FIDO_DEVICES8); |
| 454 | return NULL((void *)0); |
| 455 | } |
| 456 | skdebug(__func__, "%zu device(s) detected", ndevs); |
| 457 | if (ndevs == 0) { |
| 458 | sk = NULL((void *)0); |
| 459 | } else if (application != NULL((void *)0) && key_handle != NULL((void *)0)) { |
| 460 | skdebug(__func__, "selecting sk by cred"); |
| 461 | sk = sk_select_by_cred(devlist, ndevs, application, key_handle, |
| 462 | key_handle_len); |
| 463 | } else { |
| 464 | skdebug(__func__, "selecting sk by touch"); |
| 465 | sk = sk_select_by_touch(devlist, ndevs); |
| 466 | } |
| 467 | fido_dev_info_free(&devlist, MAX_FIDO_DEVICES8); |
| 468 | return sk; |
| 469 | } |
| 470 | |
| 471 | #ifdef WITH_OPENSSL1 |
| 472 | /* |
| 473 | * The key returned via fido_cred_pubkey_ptr() is in affine coordinates, |
| 474 | * but the API expects a SEC1 octet string. |
| 475 | */ |
| 476 | static int |
| 477 | pack_public_key_ecdsa(const fido_cred_t *cred, |
| 478 | struct sk_enroll_response *response) |
| 479 | { |
| 480 | const uint8_t *ptr; |
| 481 | BIGNUM *x = NULL((void *)0), *y = NULL((void *)0); |
| 482 | EC_POINT *q = NULL((void *)0); |
| 483 | EC_GROUP *g = NULL((void *)0); |
| 484 | int ret = -1; |
| 485 | |
| 486 | response->public_key = NULL((void *)0); |
| 487 | response->public_key_len = 0; |
| 488 | |
| 489 | if ((x = BN_new()) == NULL((void *)0) || |
| 490 | (y = BN_new()) == NULL((void *)0) || |
| 491 | (g = EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1415)) == NULL((void *)0) || |
| 492 | (q = EC_POINT_new(g)) == NULL((void *)0)) { |
| 493 | skdebug(__func__, "libcrypto setup failed"); |
| 494 | goto out; |
| 495 | } |
| 496 | if ((ptr = fido_cred_pubkey_ptr(cred)) == NULL((void *)0)) { |
| 497 | skdebug(__func__, "fido_cred_pubkey_ptr failed"); |
| 498 | goto out; |
| 499 | } |
| 500 | if (fido_cred_pubkey_len(cred) != 64) { |
| 501 | skdebug(__func__, "bad fido_cred_pubkey_len %zu", |
| 502 | fido_cred_pubkey_len(cred)); |
| 503 | goto out; |
| 504 | } |
| 505 | |
| 506 | if (BN_bin2bn(ptr, 32, x) == NULL((void *)0) || |
| 507 | BN_bin2bn(ptr + 32, 32, y) == NULL((void *)0)) { |
| 508 | skdebug(__func__, "BN_bin2bn failed"); |
| 509 | goto out; |
| 510 | } |
| 511 | if (EC_POINT_set_affine_coordinates_GFp(g, q, x, y, NULL((void *)0)) != 1) { |
| 512 | skdebug(__func__, "EC_POINT_set_affine_coordinates_GFp failed"); |
| 513 | goto out; |
| 514 | } |
| 515 | response->public_key_len = EC_POINT_point2oct(g, q, |
| 516 | POINT_CONVERSION_UNCOMPRESSED, NULL((void *)0), 0, NULL((void *)0)); |
| 517 | if (response->public_key_len == 0 || response->public_key_len > 2048) { |
| 518 | skdebug(__func__, "bad pubkey length %zu", |
| 519 | response->public_key_len); |
| 520 | goto out; |
| 521 | } |
| 522 | if ((response->public_key = malloc(response->public_key_len)) == NULL((void *)0)) { |
| 523 | skdebug(__func__, "malloc pubkey failed"); |
| 524 | goto out; |
| 525 | } |
| 526 | if (EC_POINT_point2oct(g, q, POINT_CONVERSION_UNCOMPRESSED, |
| 527 | response->public_key, response->public_key_len, NULL((void *)0)) == 0) { |
| 528 | skdebug(__func__, "EC_POINT_point2oct failed"); |
| 529 | goto out; |
| 530 | } |
| 531 | /* success */ |
| 532 | ret = 0; |
| 533 | out: |
| 534 | if (ret != 0 && response->public_key != NULL((void *)0)) { |
| 535 | memset(response->public_key, 0, response->public_key_len); |
| 536 | free(response->public_key); |
| 537 | response->public_key = NULL((void *)0); |
| 538 | } |
| 539 | EC_POINT_free(q); |
| 540 | EC_GROUP_free(g); |
| 541 | BN_clear_free(x); |
| 542 | BN_clear_free(y); |
| 543 | return ret; |
| 544 | } |
| 545 | #endif /* WITH_OPENSSL */ |
| 546 | |
| 547 | static int |
| 548 | pack_public_key_ed25519(const fido_cred_t *cred, |
| 549 | struct sk_enroll_response *response) |
| 550 | { |
| 551 | const uint8_t *ptr; |
| 552 | size_t len; |
| 553 | int ret = -1; |
| 554 | |
| 555 | response->public_key = NULL((void *)0); |
| 556 | response->public_key_len = 0; |
| 557 | |
| 558 | if ((len = fido_cred_pubkey_len(cred)) != 32) { |
| 559 | skdebug(__func__, "bad fido_cred_pubkey_len len %zu", len); |
| 560 | goto out; |
| 561 | } |
| 562 | if ((ptr = fido_cred_pubkey_ptr(cred)) == NULL((void *)0)) { |
| 563 | skdebug(__func__, "fido_cred_pubkey_ptr failed"); |
| 564 | goto out; |
| 565 | } |
| 566 | response->public_key_len = len; |
| 567 | if ((response->public_key = malloc(response->public_key_len)) == NULL((void *)0)) { |
| 568 | skdebug(__func__, "malloc pubkey failed"); |
| 569 | goto out; |
| 570 | } |
| 571 | memcpy(response->public_key, ptr, len); |
| 572 | ret = 0; |
| 573 | out: |
| 574 | if (ret != 0) |
| 575 | free(response->public_key); |
| 576 | return ret; |
| 577 | } |
| 578 | |
| 579 | static int |
| 580 | pack_public_key(uint32_t alg, const fido_cred_t *cred, |
| 581 | struct sk_enroll_response *response) |
| 582 | { |
| 583 | switch(alg) { |
| 584 | #ifdef WITH_OPENSSL1 |
| 585 | case SSH_SK_ECDSA0x00: |
| 586 | return pack_public_key_ecdsa(cred, response); |
| 587 | #endif /* WITH_OPENSSL */ |
| 588 | case SSH_SK_ED255190x01: |
| 589 | return pack_public_key_ed25519(cred, response); |
| 590 | default: |
| 591 | return -1; |
| 592 | } |
| 593 | } |
| 594 | |
| 595 | static int |
| 596 | fidoerr_to_skerr(int fidoerr) |
| 597 | { |
| 598 | switch (fidoerr) { |
| 599 | case FIDO_ERR_UNSUPPORTED_OPTION0x2b: |
| 600 | case FIDO_ERR_UNSUPPORTED_ALGORITHM0x26: |
| 601 | return SSH_SK_ERR_UNSUPPORTED-2; |
| 602 | case FIDO_ERR_PIN_REQUIRED0x36: |
| 603 | case FIDO_ERR_PIN_INVALID0x31: |
| 604 | case FIDO_ERR_OPERATION_DENIED0x27: |
| 605 | return SSH_SK_ERR_PIN_REQUIRED-3; |
| 606 | default: |
| 607 | return -1; |
| 608 | } |
| 609 | } |
| 610 | |
| 611 | static int |
| 612 | check_enroll_options(struct sk_option **options, char **devicep, |
| 613 | uint8_t *user_id, size_t user_id_len) |
| 614 | { |
| 615 | size_t i; |
| 616 | |
| 617 | if (options == NULL((void *)0)) |
| 618 | return 0; |
| 619 | for (i = 0; options[i] != NULL((void *)0); i++) { |
| 620 | if (strcmp(options[i]->name, "device") == 0) { |
| 621 | if ((*devicep = strdup(options[i]->value)) == NULL((void *)0)) { |
| 622 | skdebug(__func__, "strdup device failed"); |
| 623 | return -1; |
| 624 | } |
| 625 | skdebug(__func__, "requested device %s", *devicep); |
| 626 | } else if (strcmp(options[i]->name, "user") == 0) { |
| 627 | if (strlcpy(user_id, options[i]->value, user_id_len) >= |
| 628 | user_id_len) { |
| 629 | skdebug(__func__, "user too long"); |
| 630 | return -1; |
| 631 | } |
| 632 | skdebug(__func__, "requested user %s", |
| 633 | (char *)user_id); |
| 634 | } else { |
| 635 | skdebug(__func__, "requested unsupported option %s", |
| 636 | options[i]->name); |
| 637 | if (options[i]->required) { |
| 638 | skdebug(__func__, "unknown required option"); |
| 639 | return -1; |
| 640 | } |
| 641 | } |
| 642 | } |
| 643 | return 0; |
| 644 | } |
| 645 | |
| 646 | static int |
| 647 | key_lookup(fido_dev_t *dev, const char *application, const uint8_t *user_id, |
| 648 | size_t user_id_len, const char *pin) |
| 649 | { |
| 650 | fido_assert_t *assert = NULL((void *)0); |
| 651 | uint8_t message[32]; |
| 652 | int r = FIDO_ERR_INTERNAL-9; |
| 653 | int sk_supports_uv, uv; |
| 654 | size_t i; |
| 655 | |
| 656 | memset(message, '\0', sizeof(message)); |
| 657 | if ((assert = fido_assert_new()) == NULL((void *)0)) { |
| 658 | skdebug(__func__, "fido_assert_new failed"); |
| 659 | goto out; |
| 660 | } |
| 661 | /* generate an invalid signature on FIDO2 tokens */ |
| 662 | if ((r = fido_assert_set_clientdata(assert, message, |
| 663 | sizeof(message))) != FIDO_OK0x00) { |
| 664 | skdebug(__func__, "fido_assert_set_clientdata: %s", |
| 665 | fido_strerr(r)); |
| 666 | goto out; |
| 667 | } |
| 668 | if ((r = fido_assert_set_rp(assert, application)) != FIDO_OK0x00) { |
| 669 | skdebug(__func__, "fido_assert_set_rp: %s", fido_strerr(r)); |
| 670 | goto out; |
| 671 | } |
| 672 | if ((r = fido_assert_set_up(assert, FIDO_OPT_FALSE)) != FIDO_OK0x00) { |
| 673 | skdebug(__func__, "fido_assert_set_up: %s", fido_strerr(r)); |
| 674 | goto out; |
| 675 | } |
| 676 | uv = FIDO_OPT_OMIT; |
| 677 | if (pin == NULL((void *)0) && check_sk_options(dev, "uv", &sk_supports_uv) == 0 && |
| 678 | sk_supports_uv != -1) |
| 679 | uv = FIDO_OPT_TRUE; |
| 680 | if ((r = fido_assert_set_uv(assert, uv)) != FIDO_OK0x00) { |
| 681 | skdebug(__func__, "fido_assert_set_uv: %s", fido_strerr(r)); |
| 682 | goto out; |
| 683 | } |
| 684 | if ((r = fido_dev_get_assert(dev, assert, pin)) != FIDO_OK0x00) { |
| 685 | skdebug(__func__, "fido_dev_get_assert: %s", fido_strerr(r)); |
| 686 | goto out; |
| 687 | } |
| 688 | r = FIDO_ERR_NO_CREDENTIALS0x2e; |
| 689 | skdebug(__func__, "%zu signatures returned", fido_assert_count(assert)); |
| 690 | for (i = 0; i < fido_assert_count(assert); i++) { |
| 691 | if (fido_assert_user_id_len(assert, i) == user_id_len && |
| 692 | memcmp(fido_assert_user_id_ptr(assert, i), user_id, |
| 693 | user_id_len) == 0) { |
| 694 | skdebug(__func__, "credential exists"); |
| 695 | r = FIDO_OK0x00; |
| 696 | goto out; |
| 697 | } |
| 698 | } |
| 699 | out: |
| 700 | fido_assert_free(&assert); |
| 701 | |
| 702 | return r; |
| 703 | } |
| 704 | |
| 705 | int |
| 706 | sk_enrollssh_sk_enroll(uint32_t alg, const uint8_t *challenge, size_t challenge_len, |
| 707 | const char *application, uint8_t flags, const char *pin, |
| 708 | struct sk_option **options, struct sk_enroll_response **enroll_response) |
| 709 | { |
| 710 | fido_cred_t *cred = NULL((void *)0); |
| 711 | const uint8_t *ptr; |
| 712 | uint8_t user_id[32]; |
| 713 | struct sk_usbhid *sk = NULL((void *)0); |
| 714 | struct sk_enroll_response *response = NULL((void *)0); |
| 715 | size_t len; |
| 716 | int credprot; |
| 717 | int cose_alg; |
| 718 | int ret = SSH_SK_ERR_GENERAL-1; |
| 719 | int r; |
| 720 | char *device = NULL((void *)0); |
| 721 | |
| 722 | fido_init(SSH_FIDO_INIT_ARG0); |
| 723 | |
| 724 | if (enroll_response == NULL((void *)0)) { |
| 725 | skdebug(__func__, "enroll_response == NULL"); |
| 726 | goto out; |
| 727 | } |
| 728 | *enroll_response = NULL((void *)0); |
| 729 | memset(user_id, 0, sizeof(user_id)); |
| 730 | if (check_enroll_options(options, &device, user_id, |
| 731 | sizeof(user_id)) != 0) |
| 732 | goto out; /* error already logged */ |
| 733 | |
| 734 | switch(alg) { |
| 735 | #ifdef WITH_OPENSSL1 |
| 736 | case SSH_SK_ECDSA0x00: |
| 737 | cose_alg = COSE_ES256-7; |
| 738 | break; |
| 739 | #endif /* WITH_OPENSSL */ |
| 740 | case SSH_SK_ED255190x01: |
| 741 | cose_alg = COSE_EDDSA-8; |
| 742 | break; |
| 743 | default: |
| 744 | skdebug(__func__, "unsupported key type %d", alg); |
| 745 | goto out; |
| 746 | } |
| 747 | if (device != NULL((void *)0)) |
| 748 | sk = sk_open(device); |
| 749 | else |
| 750 | sk = sk_probe(NULL((void *)0), NULL((void *)0), 0, 0); |
| 751 | if (sk == NULL((void *)0)) { |
| 752 | ret = SSH_SK_ERR_DEVICE_NOT_FOUND-4; |
| 753 | skdebug(__func__, "failed to find sk"); |
| 754 | goto out; |
| 755 | } |
| 756 | skdebug(__func__, "using device %s", sk->path); |
| 757 | if ((flags & SSH_SK_RESIDENT_KEY0x20) != 0 && |
| 758 | (flags & SSH_SK_FORCE_OPERATION0x10) == 0 && |
| 759 | (r = key_lookup(sk->dev, application, user_id, sizeof(user_id), |
| 760 | pin)) != FIDO_ERR_NO_CREDENTIALS0x2e) { |
| 761 | if (r != FIDO_OK0x00) { |
| 762 | ret = fidoerr_to_skerr(r); |
| 763 | skdebug(__func__, "key_lookup failed"); |
| 764 | } else { |
| 765 | ret = SSH_SK_ERR_CREDENTIAL_EXISTS-5; |
| 766 | skdebug(__func__, "key exists"); |
| 767 | } |
| 768 | goto out; |
| 769 | } |
| 770 | if ((cred = fido_cred_new()) == NULL((void *)0)) { |
| 771 | skdebug(__func__, "fido_cred_new failed"); |
| 772 | goto out; |
| 773 | } |
| 774 | if ((r = fido_cred_set_type(cred, cose_alg)) != FIDO_OK0x00) { |
| 775 | skdebug(__func__, "fido_cred_set_type: %s", fido_strerr(r)); |
| 776 | goto out; |
| 777 | } |
| 778 | if ((r = fido_cred_set_clientdata(cred, |
| 779 | challenge, challenge_len)) != FIDO_OK0x00) { |
| 780 | skdebug(__func__, "fido_cred_set_clientdata: %s", |
| 781 | fido_strerr(r)); |
| 782 | goto out; |
| 783 | } |
| 784 | if ((r = fido_cred_set_rk(cred, (flags & SSH_SK_RESIDENT_KEY0x20) != 0 ? |
| 785 | FIDO_OPT_TRUE : FIDO_OPT_OMIT)) != FIDO_OK0x00) { |
| 786 | skdebug(__func__, "fido_cred_set_rk: %s", fido_strerr(r)); |
| 787 | goto out; |
| 788 | } |
| 789 | if ((r = fido_cred_set_user(cred, user_id, sizeof(user_id), |
| 790 | "openssh", "openssh", NULL((void *)0))) != FIDO_OK0x00) { |
| 791 | skdebug(__func__, "fido_cred_set_user: %s", fido_strerr(r)); |
| 792 | goto out; |
| 793 | } |
| 794 | if ((r = fido_cred_set_rp(cred, application, NULL((void *)0))) != FIDO_OK0x00) { |
| 795 | skdebug(__func__, "fido_cred_set_rp: %s", fido_strerr(r)); |
| 796 | goto out; |
| 797 | } |
| 798 | if ((flags & (SSH_SK_RESIDENT_KEY0x20|SSH_SK_USER_VERIFICATION_REQD0x04)) != 0) { |
| 799 | if (!fido_dev_supports_cred_prot(sk->dev)) { |
| 800 | skdebug(__func__, "%s does not support credprot, " |
| 801 | "refusing to create unprotected " |
| 802 | "resident/verify-required key", sk->path); |
| 803 | ret = SSH_SK_ERR_UNSUPPORTED-2; |
| 804 | goto out; |
| 805 | } |
| 806 | if ((flags & SSH_SK_USER_VERIFICATION_REQD0x04)) |
| 807 | credprot = FIDO_CRED_PROT_UV_REQUIRED0x03; |
| 808 | else |
| 809 | credprot = FIDO_CRED_PROT_UV_OPTIONAL_WITH_ID0x02; |
| 810 | |
| 811 | if ((r = fido_cred_set_prot(cred, credprot)) != FIDO_OK0x00) { |
| 812 | skdebug(__func__, "fido_cred_set_prot: %s", |
| 813 | fido_strerr(r)); |
| 814 | ret = fidoerr_to_skerr(r); |
| 815 | goto out; |
| 816 | } |
| 817 | } |
| 818 | if ((r = fido_dev_make_cred(sk->dev, cred, pin)) != FIDO_OK0x00) { |
| 819 | skdebug(__func__, "fido_dev_make_cred: %s", fido_strerr(r)); |
| 820 | ret = fidoerr_to_skerr(r); |
| 821 | goto out; |
| 822 | } |
| 823 | if (fido_cred_x5c_ptr(cred) != NULL((void *)0)) { |
| 824 | if ((r = fido_cred_verify(cred)) != FIDO_OK0x00) { |
| 825 | skdebug(__func__, "fido_cred_verify: %s", |
| 826 | fido_strerr(r)); |
| 827 | goto out; |
| 828 | } |
| 829 | } else { |
| 830 | skdebug(__func__, "self-attested credential"); |
| 831 | if ((r = fido_cred_verify_self(cred)) != FIDO_OK0x00) { |
| 832 | skdebug(__func__, "fido_cred_verify_self: %s", |
| 833 | fido_strerr(r)); |
| 834 | goto out; |
| 835 | } |
| 836 | } |
| 837 | if ((response = calloc(1, sizeof(*response))) == NULL((void *)0)) { |
| 838 | skdebug(__func__, "calloc response failed"); |
| 839 | goto out; |
| 840 | } |
| 841 | response->flags = flags; |
| 842 | if (pack_public_key(alg, cred, response) != 0) { |
| 843 | skdebug(__func__, "pack_public_key failed"); |
| 844 | goto out; |
| 845 | } |
| 846 | if ((ptr = fido_cred_id_ptr(cred)) != NULL((void *)0)) { |
| 847 | len = fido_cred_id_len(cred); |
| 848 | if ((response->key_handle = calloc(1, len)) == NULL((void *)0)) { |
| 849 | skdebug(__func__, "calloc key handle failed"); |
| 850 | goto out; |
| 851 | } |
| 852 | memcpy(response->key_handle, ptr, len); |
| 853 | response->key_handle_len = len; |
| 854 | } |
| 855 | if ((ptr = fido_cred_sig_ptr(cred)) != NULL((void *)0)) { |
| 856 | len = fido_cred_sig_len(cred); |
| 857 | if ((response->signature = calloc(1, len)) == NULL((void *)0)) { |
| 858 | skdebug(__func__, "calloc signature failed"); |
| 859 | goto out; |
| 860 | } |
| 861 | memcpy(response->signature, ptr, len); |
| 862 | response->signature_len = len; |
| 863 | } |
| 864 | if ((ptr = fido_cred_x5c_ptr(cred)) != NULL((void *)0)) { |
| 865 | len = fido_cred_x5c_len(cred); |
| 866 | skdebug(__func__, "attestation cert len=%zu", len); |
| 867 | if ((response->attestation_cert = calloc(1, len)) == NULL((void *)0)) { |
| 868 | skdebug(__func__, "calloc attestation cert failed"); |
| 869 | goto out; |
| 870 | } |
| 871 | memcpy(response->attestation_cert, ptr, len); |
| 872 | response->attestation_cert_len = len; |
| 873 | } |
| 874 | if ((ptr = fido_cred_authdata_ptr(cred)) != NULL((void *)0)) { |
| 875 | len = fido_cred_authdata_len(cred); |
| 876 | skdebug(__func__, "authdata len=%zu", len); |
| 877 | if ((response->authdata = calloc(1, len)) == NULL((void *)0)) { |
| 878 | skdebug(__func__, "calloc authdata failed"); |
| 879 | goto out; |
| 880 | } |
| 881 | memcpy(response->authdata, ptr, len); |
| 882 | response->authdata_len = len; |
| 883 | } |
| 884 | *enroll_response = response; |
| 885 | response = NULL((void *)0); |
| 886 | ret = 0; |
| 887 | out: |
| 888 | free(device); |
| 889 | if (response != NULL((void *)0)) { |
| 890 | free(response->public_key); |
| 891 | free(response->key_handle); |
| 892 | free(response->signature); |
| 893 | free(response->attestation_cert); |
| 894 | free(response->authdata); |
| 895 | free(response); |
| 896 | } |
| 897 | sk_close(sk); |
| 898 | fido_cred_free(&cred); |
| 899 | return ret; |
| 900 | } |
| 901 | |
| 902 | #ifdef WITH_OPENSSL1 |
| 903 | static int |
| 904 | pack_sig_ecdsa(fido_assert_t *assert, struct sk_sign_response *response) |
| 905 | { |
| 906 | ECDSA_SIG *sig = NULL((void *)0); |
| 907 | const BIGNUM *sig_r, *sig_s; |
| 908 | const unsigned char *cp; |
| 909 | size_t sig_len; |
| 910 | int ret = -1; |
| 911 | |
| 912 | cp = fido_assert_sig_ptr(assert, 0); |
| 913 | sig_len = fido_assert_sig_len(assert, 0); |
| 914 | if ((sig = d2i_ECDSA_SIG(NULL((void *)0), &cp, sig_len)) == NULL((void *)0)) { |
| 915 | skdebug(__func__, "d2i_ECDSA_SIG failed"); |
| 916 | goto out; |
| 917 | } |
| 918 | ECDSA_SIG_get0(sig, &sig_r, &sig_s); |
| 919 | response->sig_r_len = BN_num_bytes(sig_r)((BN_num_bits(sig_r)+7)/8); |
| 920 | response->sig_s_len = BN_num_bytes(sig_s)((BN_num_bits(sig_s)+7)/8); |
| 921 | if ((response->sig_r = calloc(1, response->sig_r_len)) == NULL((void *)0) || |
| 922 | (response->sig_s = calloc(1, response->sig_s_len)) == NULL((void *)0)) { |
| 923 | skdebug(__func__, "calloc signature failed"); |
| 924 | goto out; |
| 925 | } |
| 926 | BN_bn2bin(sig_r, response->sig_r); |
| 927 | BN_bn2bin(sig_s, response->sig_s); |
| 928 | ret = 0; |
| 929 | out: |
| 930 | ECDSA_SIG_free(sig); |
| 931 | if (ret != 0) { |
| 932 | free(response->sig_r); |
| 933 | free(response->sig_s); |
| 934 | response->sig_r = NULL((void *)0); |
| 935 | response->sig_s = NULL((void *)0); |
| 936 | } |
| 937 | return ret; |
| 938 | } |
| 939 | #endif /* WITH_OPENSSL */ |
| 940 | |
| 941 | static int |
| 942 | pack_sig_ed25519(fido_assert_t *assert, struct sk_sign_response *response) |
| 943 | { |
| 944 | const unsigned char *ptr; |
| 945 | size_t len; |
| 946 | int ret = -1; |
| 947 | |
| 948 | ptr = fido_assert_sig_ptr(assert, 0); |
| 949 | len = fido_assert_sig_len(assert, 0); |
| 950 | if (len != 64) { |
| 951 | skdebug(__func__, "bad length %zu", len); |
| 952 | goto out; |
| 953 | } |
| 954 | response->sig_r_len = len; |
| 955 | if ((response->sig_r = calloc(1, response->sig_r_len)) == NULL((void *)0)) { |
| 956 | skdebug(__func__, "calloc signature failed"); |
| 957 | goto out; |
| 958 | } |
| 959 | memcpy(response->sig_r, ptr, len); |
| 960 | ret = 0; |
| 961 | out: |
| 962 | if (ret != 0) { |
| 963 | free(response->sig_r); |
| 964 | response->sig_r = NULL((void *)0); |
| 965 | } |
| 966 | return ret; |
| 967 | } |
| 968 | |
| 969 | static int |
| 970 | pack_sig(uint32_t alg, fido_assert_t *assert, |
| 971 | struct sk_sign_response *response) |
| 972 | { |
| 973 | switch(alg) { |
| 974 | #ifdef WITH_OPENSSL1 |
| 975 | case SSH_SK_ECDSA0x00: |
| 976 | return pack_sig_ecdsa(assert, response); |
| 977 | #endif /* WITH_OPENSSL */ |
| 978 | case SSH_SK_ED255190x01: |
| 979 | return pack_sig_ed25519(assert, response); |
| 980 | default: |
| 981 | return -1; |
| 982 | } |
| 983 | } |
| 984 | |
| 985 | /* Checks sk_options for sk_sign() and sk_load_resident_keys() */ |
| 986 | static int |
| 987 | check_sign_load_resident_options(struct sk_option **options, char **devicep) |
| 988 | { |
| 989 | size_t i; |
| 990 | |
| 991 | if (options == NULL((void *)0)) |
| 992 | return 0; |
| 993 | for (i = 0; options[i] != NULL((void *)0); i++) { |
| 994 | if (strcmp(options[i]->name, "device") == 0) { |
| 995 | if ((*devicep = strdup(options[i]->value)) == NULL((void *)0)) { |
| 996 | skdebug(__func__, "strdup device failed"); |
| 997 | return -1; |
| 998 | } |
| 999 | skdebug(__func__, "requested device %s", *devicep); |
| 1000 | } else { |
| 1001 | skdebug(__func__, "requested unsupported option %s", |
| 1002 | options[i]->name); |
| 1003 | if (options[i]->required) { |
| 1004 | skdebug(__func__, "unknown required option"); |
| 1005 | return -1; |
| 1006 | } |
| 1007 | } |
| 1008 | } |
| 1009 | return 0; |
| 1010 | } |
| 1011 | |
| 1012 | int |
| 1013 | sk_signssh_sk_sign(uint32_t alg, const uint8_t *data, size_t datalen, |
| 1014 | const char *application, |
| 1015 | const uint8_t *key_handle, size_t key_handle_len, |
| 1016 | uint8_t flags, const char *pin, struct sk_option **options, |
| 1017 | struct sk_sign_response **sign_response) |
| 1018 | { |
| 1019 | fido_assert_t *assert = NULL((void *)0); |
| 1020 | char *device = NULL((void *)0); |
| 1021 | struct sk_usbhid *sk = NULL((void *)0); |
| 1022 | struct sk_sign_response *response = NULL((void *)0); |
| 1023 | int ret = SSH_SK_ERR_GENERAL-1, internal_uv; |
| 1024 | int r; |
| 1025 | |
| 1026 | fido_init(SSH_FIDO_INIT_ARG0); |
| 1027 | |
| 1028 | if (sign_response == NULL((void *)0)) { |
| 1029 | skdebug(__func__, "sign_response == NULL"); |
| 1030 | goto out; |
| 1031 | } |
| 1032 | *sign_response = NULL((void *)0); |
| 1033 | if (check_sign_load_resident_options(options, &device) != 0) |
| 1034 | goto out; /* error already logged */ |
| 1035 | if (device != NULL((void *)0)) |
| 1036 | sk = sk_open(device); |
| 1037 | else if (pin != NULL((void *)0) || (flags & SSH_SK_USER_VERIFICATION_REQD0x04)) |
| 1038 | sk = sk_probe(NULL((void *)0), NULL((void *)0), 0, 0); |
| 1039 | else |
| 1040 | sk = sk_probe(application, key_handle, key_handle_len, 0); |
| 1041 | if (sk == NULL((void *)0)) { |
| 1042 | ret = SSH_SK_ERR_DEVICE_NOT_FOUND-4; |
| 1043 | skdebug(__func__, "failed to find sk"); |
| 1044 | goto out; |
| 1045 | } |
| 1046 | if ((assert = fido_assert_new()) == NULL((void *)0)) { |
| 1047 | skdebug(__func__, "fido_assert_new failed"); |
| 1048 | goto out; |
| 1049 | } |
| 1050 | if ((r = fido_assert_set_clientdata(assert, |
| 1051 | data, datalen)) != FIDO_OK0x00) { |
| 1052 | skdebug(__func__, "fido_assert_set_clientdata: %s", |
| 1053 | fido_strerr(r)); |
| 1054 | goto out; |
| 1055 | } |
| 1056 | if ((r = fido_assert_set_rp(assert, application)) != FIDO_OK0x00) { |
| 1057 | skdebug(__func__, "fido_assert_set_rp: %s", fido_strerr(r)); |
| 1058 | goto out; |
| 1059 | } |
| 1060 | if ((r = fido_assert_allow_cred(assert, key_handle, |
| 1061 | key_handle_len)) != FIDO_OK0x00) { |
| 1062 | skdebug(__func__, "fido_assert_allow_cred: %s", fido_strerr(r)); |
| 1063 | goto out; |
| 1064 | } |
| 1065 | if ((r = fido_assert_set_up(assert, |
| 1066 | (flags & SSH_SK_USER_PRESENCE_REQD0x01) ? |
| 1067 | FIDO_OPT_TRUE : FIDO_OPT_FALSE)) != FIDO_OK0x00) { |
| 1068 | skdebug(__func__, "fido_assert_set_up: %s", fido_strerr(r)); |
| 1069 | goto out; |
| 1070 | } |
| 1071 | if (pin == NULL((void *)0) && (flags & SSH_SK_USER_VERIFICATION_REQD0x04)) { |
| 1072 | if (check_sk_options(sk->dev, "uv", &internal_uv) < 0 || |
| 1073 | internal_uv != 1) { |
| 1074 | skdebug(__func__, "check_sk_options uv"); |
| 1075 | ret = SSH_SK_ERR_PIN_REQUIRED-3; |
| 1076 | goto out; |
| 1077 | } |
| 1078 | if ((r = fido_assert_set_uv(assert, |
| 1079 | FIDO_OPT_TRUE)) != FIDO_OK0x00) { |
| 1080 | skdebug(__func__, "fido_assert_set_uv: %s", |
| 1081 | fido_strerr(r)); |
| 1082 | ret = fidoerr_to_skerr(r); |
| 1083 | goto out; |
| 1084 | } |
| 1085 | } |
| 1086 | if ((r = fido_dev_get_assert(sk->dev, assert, pin)) != FIDO_OK0x00) { |
| 1087 | skdebug(__func__, "fido_dev_get_assert: %s", fido_strerr(r)); |
| 1088 | ret = fidoerr_to_skerr(r); |
| 1089 | goto out; |
| 1090 | } |
| 1091 | if ((response = calloc(1, sizeof(*response))) == NULL((void *)0)) { |
| 1092 | skdebug(__func__, "calloc response failed"); |
| 1093 | goto out; |
| 1094 | } |
| 1095 | response->flags = fido_assert_flags(assert, 0); |
| 1096 | response->counter = fido_assert_sigcount(assert, 0); |
| 1097 | if (pack_sig(alg, assert, response) != 0) { |
| 1098 | skdebug(__func__, "pack_sig failed"); |
| 1099 | goto out; |
| 1100 | } |
| 1101 | *sign_response = response; |
| 1102 | response = NULL((void *)0); |
| 1103 | ret = 0; |
| 1104 | out: |
| 1105 | free(device); |
| 1106 | if (response != NULL((void *)0)) { |
| 1107 | free(response->sig_r); |
| 1108 | free(response->sig_s); |
| 1109 | free(response); |
| 1110 | } |
| 1111 | sk_close(sk); |
| 1112 | fido_assert_free(&assert); |
| 1113 | return ret; |
| 1114 | } |
| 1115 | |
| 1116 | static int |
| 1117 | read_rks(struct sk_usbhid *sk, const char *pin, |
| 1118 | struct sk_resident_key ***rksp, size_t *nrksp) |
| 1119 | { |
| 1120 | int ret = SSH_SK_ERR_GENERAL-1, r = -1, internal_uv; |
| 1121 | fido_credman_metadata_t *metadata = NULL((void *)0); |
| 1122 | fido_credman_rp_t *rp = NULL((void *)0); |
| 1123 | fido_credman_rk_t *rk = NULL((void *)0); |
| 1124 | size_t i, j, nrp, nrk, user_id_len; |
| 1125 | const fido_cred_t *cred; |
| 1126 | const char *rp_id, *rp_name, *user_name; |
| 1127 | struct sk_resident_key *srk = NULL((void *)0), **tmp; |
| 1128 | const u_char *user_id; |
| 1129 | |
| 1130 | if (pin == NULL((void *)0)) { |
| 1131 | skdebug(__func__, "no PIN specified"); |
| 1132 | ret = SSH_SK_ERR_PIN_REQUIRED-3; |
| 1133 | goto out; |
| 1134 | } |
| 1135 | if ((metadata = fido_credman_metadata_new()) == NULL((void *)0)) { |
| 1136 | skdebug(__func__, "alloc failed"); |
| 1137 | goto out; |
| 1138 | } |
| 1139 | if (check_sk_options(sk->dev, "uv", &internal_uv) != 0) { |
| 1140 | skdebug(__func__, "check_sk_options failed"); |
| 1141 | goto out; |
| 1142 | } |
| 1143 | |
| 1144 | if ((r = fido_credman_get_dev_metadata(sk->dev, metadata, pin)) != 0) { |
| 1145 | if (r == FIDO_ERR_INVALID_COMMAND0x01) { |
| 1146 | skdebug(__func__, "device %s does not support " |
| 1147 | "resident keys", sk->path); |
| 1148 | ret = 0; |
| 1149 | goto out; |
| 1150 | } |
| 1151 | skdebug(__func__, "get metadata for %s failed: %s", |
| 1152 | sk->path, fido_strerr(r)); |
| 1153 | ret = fidoerr_to_skerr(r); |
| 1154 | goto out; |
| 1155 | } |
| 1156 | skdebug(__func__, "existing %llu, remaining %llu", |
| 1157 | (unsigned long long)fido_credman_rk_existing(metadata), |
| 1158 | (unsigned long long)fido_credman_rk_remaining(metadata)); |
| 1159 | if ((rp = fido_credman_rp_new()) == NULL((void *)0)) { |
| 1160 | skdebug(__func__, "alloc rp failed"); |
| 1161 | goto out; |
| 1162 | } |
| 1163 | if ((r = fido_credman_get_dev_rp(sk->dev, rp, pin)) != 0) { |
| 1164 | skdebug(__func__, "get RPs for %s failed: %s", |
| 1165 | sk->path, fido_strerr(r)); |
| 1166 | goto out; |
| 1167 | } |
| 1168 | nrp = fido_credman_rp_count(rp); |
| 1169 | skdebug(__func__, "Device %s has resident keys for %zu RPs", |
| 1170 | sk->path, nrp); |
| 1171 | |
| 1172 | /* Iterate over RP IDs that have resident keys */ |
| 1173 | for (i = 0; i < nrp; i++) { |
| 1174 | rp_id = fido_credman_rp_id(rp, i); |
| 1175 | rp_name = fido_credman_rp_name(rp, i); |
| 1176 | skdebug(__func__, "rp %zu: name=\"%s\" id=\"%s\" hashlen=%zu", |
| 1177 | i, rp_name == NULL((void *)0) ? "(none)" : rp_name, |
| 1178 | rp_id == NULL((void *)0) ? "(none)" : rp_id, |
| 1179 | fido_credman_rp_id_hash_len(rp, i)); |
| 1180 | |
| 1181 | /* Skip non-SSH RP IDs */ |
| 1182 | if (rp_id == NULL((void *)0) || |
| 1183 | strncasecmp(fido_credman_rp_id(rp, i), "ssh:", 4) != 0) |
| 1184 | continue; |
| 1185 | |
| 1186 | fido_credman_rk_free(&rk); |
| 1187 | if ((rk = fido_credman_rk_new()) == NULL((void *)0)) { |
| 1188 | skdebug(__func__, "alloc rk failed"); |
| 1189 | goto out; |
| 1190 | } |
| 1191 | if ((r = fido_credman_get_dev_rk(sk->dev, |
| 1192 | fido_credman_rp_id(rp, i), rk, pin)) != 0) { |
| 1193 | skdebug(__func__, "get RKs for %s slot %zu failed: %s", |
| 1194 | sk->path, i, fido_strerr(r)); |
| 1195 | goto out; |
| 1196 | } |
| 1197 | nrk = fido_credman_rk_count(rk); |
| 1198 | skdebug(__func__, "RP \"%s\" has %zu resident keys", |
| 1199 | fido_credman_rp_id(rp, i), nrk); |
| 1200 | |
| 1201 | /* Iterate over resident keys for this RP ID */ |
| 1202 | for (j = 0; j < nrk; j++) { |
| 1203 | if ((cred = fido_credman_rk(rk, j)) == NULL((void *)0)) { |
| 1204 | skdebug(__func__, "no RK in slot %zu", j); |
| 1205 | continue; |
| 1206 | } |
| 1207 | if ((user_name = fido_cred_user_name(cred)) == NULL((void *)0)) |
| 1208 | user_name = ""; |
| 1209 | user_id = fido_cred_user_id_ptr(cred); |
| 1210 | user_id_len = fido_cred_user_id_len(cred); |
| 1211 | skdebug(__func__, "Device %s RP \"%s\" user \"%s\" " |
| 1212 | "uidlen %zu slot %zu: type %d flags 0x%02x " |
| 1213 | "prot 0x%02x", sk->path, rp_id, user_name, |
| 1214 | user_id_len, j, fido_cred_type(cred), |
| 1215 | fido_cred_flags(cred), fido_cred_prot(cred)); |
| 1216 | |
| 1217 | /* build response entry */ |
| 1218 | if ((srk = calloc(1, sizeof(*srk))) == NULL((void *)0) || |
| 1219 | (srk->key.key_handle = calloc(1, |
| 1220 | fido_cred_id_len(cred))) == NULL((void *)0) || |
| 1221 | (srk->application = strdup(rp_id)) == NULL((void *)0) || |
| 1222 | (user_id_len > 0 && |
| 1223 | (srk->user_id = calloc(1, user_id_len)) == NULL((void *)0))) { |
| 1224 | skdebug(__func__, "alloc sk_resident_key"); |
| 1225 | goto out; |
| 1226 | } |
| 1227 | |
| 1228 | srk->key.key_handle_len = fido_cred_id_len(cred); |
| 1229 | memcpy(srk->key.key_handle, fido_cred_id_ptr(cred), |
| 1230 | srk->key.key_handle_len); |
| 1231 | srk->user_id_len = user_id_len; |
| 1232 | if (srk->user_id_len != 0) |
| 1233 | memcpy(srk->user_id, user_id, srk->user_id_len); |
| 1234 | |
| 1235 | switch (fido_cred_type(cred)) { |
| 1236 | case COSE_ES256-7: |
| 1237 | srk->alg = SSH_SK_ECDSA0x00; |
| 1238 | break; |
| 1239 | case COSE_EDDSA-8: |
| 1240 | srk->alg = SSH_SK_ED255190x01; |
| 1241 | break; |
| 1242 | default: |
| 1243 | skdebug(__func__, "unsupported key type %d", |
| 1244 | fido_cred_type(cred)); |
| 1245 | goto out; /* XXX free rk and continue */ |
| 1246 | } |
| 1247 | |
| 1248 | if (fido_cred_prot(cred) == FIDO_CRED_PROT_UV_REQUIRED0x03 |
| 1249 | && internal_uv == -1) |
| 1250 | srk->flags |= SSH_SK_USER_VERIFICATION_REQD0x04; |
| 1251 | |
| 1252 | if ((r = pack_public_key(srk->alg, cred, |
Although the value stored to 'r' is used in the enclosing expression, the value is never actually read from 'r' | |
| 1253 | &srk->key)) != 0) { |
| 1254 | skdebug(__func__, "pack public key failed"); |
| 1255 | goto out; |
| 1256 | } |
| 1257 | /* append */ |
| 1258 | if ((tmp = recallocarray(*rksp, *nrksp, (*nrksp) + 1, |
| 1259 | sizeof(**rksp))) == NULL((void *)0)) { |
| 1260 | skdebug(__func__, "alloc rksp"); |
| 1261 | goto out; |
| 1262 | } |
| 1263 | *rksp = tmp; |
| 1264 | (*rksp)[(*nrksp)++] = srk; |
| 1265 | srk = NULL((void *)0); |
| 1266 | } |
| 1267 | } |
| 1268 | /* Success */ |
| 1269 | ret = 0; |
| 1270 | out: |
| 1271 | if (srk != NULL((void *)0)) { |
| 1272 | free(srk->application); |
| 1273 | freezero(srk->key.public_key, srk->key.public_key_len); |
| 1274 | freezero(srk->key.key_handle, srk->key.key_handle_len); |
| 1275 | freezero(srk->user_id, srk->user_id_len); |
| 1276 | freezero(srk, sizeof(*srk)); |
| 1277 | } |
| 1278 | fido_credman_rp_free(&rp); |
| 1279 | fido_credman_rk_free(&rk); |
| 1280 | fido_credman_metadata_free(&metadata); |
| 1281 | return ret; |
| 1282 | } |
| 1283 | |
| 1284 | int |
| 1285 | sk_load_resident_keysssh_sk_load_resident_keys(const char *pin, struct sk_option **options, |
| 1286 | struct sk_resident_key ***rksp, size_t *nrksp) |
| 1287 | { |
| 1288 | int ret = SSH_SK_ERR_GENERAL-1, r = -1; |
| 1289 | size_t i, nrks = 0; |
| 1290 | struct sk_resident_key **rks = NULL((void *)0); |
| 1291 | struct sk_usbhid *sk = NULL((void *)0); |
| 1292 | char *device = NULL((void *)0); |
| 1293 | |
| 1294 | *rksp = NULL((void *)0); |
| 1295 | *nrksp = 0; |
| 1296 | |
| 1297 | fido_init(SSH_FIDO_INIT_ARG0); |
| 1298 | |
| 1299 | if (check_sign_load_resident_options(options, &device) != 0) |
| 1300 | goto out; /* error already logged */ |
| 1301 | if (device != NULL((void *)0)) |
| 1302 | sk = sk_open(device); |
| 1303 | else |
| 1304 | sk = sk_probe(NULL((void *)0), NULL((void *)0), 0, 1); |
| 1305 | if (sk == NULL((void *)0)) { |
| 1306 | ret = SSH_SK_ERR_DEVICE_NOT_FOUND-4; |
| 1307 | skdebug(__func__, "failed to find sk"); |
| 1308 | goto out; |
| 1309 | } |
| 1310 | skdebug(__func__, "trying %s", sk->path); |
| 1311 | if ((r = read_rks(sk, pin, &rks, &nrks)) != 0) { |
| 1312 | skdebug(__func__, "read_rks failed for %s", sk->path); |
| 1313 | ret = r; |
| 1314 | goto out; |
| 1315 | } |
| 1316 | /* success, unless we have no keys but a specific error */ |
| 1317 | if (nrks > 0 || ret == SSH_SK_ERR_GENERAL-1) |
| 1318 | ret = 0; |
| 1319 | *rksp = rks; |
| 1320 | *nrksp = nrks; |
| 1321 | rks = NULL((void *)0); |
| 1322 | nrks = 0; |
| 1323 | out: |
| 1324 | sk_close(sk); |
| 1325 | for (i = 0; i < nrks; i++) { |
| 1326 | free(rks[i]->application); |
| 1327 | freezero(rks[i]->key.public_key, rks[i]->key.public_key_len); |
| 1328 | freezero(rks[i]->key.key_handle, rks[i]->key.key_handle_len); |
| 1329 | freezero(rks[i]->user_id, rks[i]->user_id_len); |
| 1330 | freezero(rks[i], sizeof(*rks[i])); |
| 1331 | } |
| 1332 | free(device); |
| 1333 | free(rks); |
| 1334 | return ret; |
| 1335 | } |
| 1336 |