dtucker@openbsd.org | 9816fc5 | 2016-06-16 11:00:17 +0000 | [diff] [blame] | 1 | /* $OpenBSD: sshbuf-getput-basic.c,v 1.6 2016/06/16 11:00:17 dtucker Exp $ */ |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 2 | /* |
| 3 | * Copyright (c) 2011 Damien Miller |
| 4 | * |
| 5 | * Permission to use, copy, modify, and distribute this software for any |
| 6 | * purpose with or without fee is hereby granted, provided that the above |
| 7 | * copyright notice and this permission notice appear in all copies. |
| 8 | * |
| 9 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| 10 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| 11 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| 12 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 13 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| 14 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
| 15 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 16 | */ |
| 17 | |
Damien Miller | e5b9f0f | 2014-05-15 14:58:07 +1000 | [diff] [blame] | 18 | #define SSHBUF_INTERNAL |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 19 | #include "includes.h" |
| 20 | |
| 21 | #include <sys/types.h> |
dtucker@openbsd.org | 9816fc5 | 2016-06-16 11:00:17 +0000 | [diff] [blame] | 22 | |
| 23 | #include <stdarg.h> |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 24 | #include <stdlib.h> |
| 25 | #include <stdio.h> |
| 26 | #include <string.h> |
| 27 | |
| 28 | #include "ssherr.h" |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 29 | #include "sshbuf.h" |
| 30 | |
| 31 | int |
| 32 | sshbuf_get(struct sshbuf *buf, void *v, size_t len) |
| 33 | { |
| 34 | const u_char *p = sshbuf_ptr(buf); |
| 35 | int r; |
| 36 | |
| 37 | if ((r = sshbuf_consume(buf, len)) < 0) |
| 38 | return r; |
djm@openbsd.org | a7f49dc | 2015-01-12 15:18:07 +0000 | [diff] [blame] | 39 | if (v != NULL && len != 0) |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 40 | memcpy(v, p, len); |
| 41 | return 0; |
| 42 | } |
| 43 | |
| 44 | int |
| 45 | sshbuf_get_u64(struct sshbuf *buf, u_int64_t *valp) |
| 46 | { |
| 47 | const u_char *p = sshbuf_ptr(buf); |
| 48 | int r; |
| 49 | |
| 50 | if ((r = sshbuf_consume(buf, 8)) < 0) |
| 51 | return r; |
| 52 | if (valp != NULL) |
| 53 | *valp = PEEK_U64(p); |
| 54 | return 0; |
| 55 | } |
| 56 | |
| 57 | int |
| 58 | sshbuf_get_u32(struct sshbuf *buf, u_int32_t *valp) |
| 59 | { |
| 60 | const u_char *p = sshbuf_ptr(buf); |
| 61 | int r; |
| 62 | |
| 63 | if ((r = sshbuf_consume(buf, 4)) < 0) |
| 64 | return r; |
| 65 | if (valp != NULL) |
| 66 | *valp = PEEK_U32(p); |
| 67 | return 0; |
| 68 | } |
| 69 | |
| 70 | int |
| 71 | sshbuf_get_u16(struct sshbuf *buf, u_int16_t *valp) |
| 72 | { |
| 73 | const u_char *p = sshbuf_ptr(buf); |
| 74 | int r; |
| 75 | |
| 76 | if ((r = sshbuf_consume(buf, 2)) < 0) |
| 77 | return r; |
| 78 | if (valp != NULL) |
| 79 | *valp = PEEK_U16(p); |
| 80 | return 0; |
| 81 | } |
| 82 | |
| 83 | int |
| 84 | sshbuf_get_u8(struct sshbuf *buf, u_char *valp) |
| 85 | { |
| 86 | const u_char *p = sshbuf_ptr(buf); |
| 87 | int r; |
| 88 | |
| 89 | if ((r = sshbuf_consume(buf, 1)) < 0) |
| 90 | return r; |
| 91 | if (valp != NULL) |
| 92 | *valp = (u_int8_t)*p; |
| 93 | return 0; |
| 94 | } |
| 95 | |
| 96 | int |
| 97 | sshbuf_get_string(struct sshbuf *buf, u_char **valp, size_t *lenp) |
| 98 | { |
| 99 | const u_char *val; |
| 100 | size_t len; |
| 101 | int r; |
| 102 | |
| 103 | if (valp != NULL) |
| 104 | *valp = NULL; |
| 105 | if (lenp != NULL) |
| 106 | *lenp = 0; |
| 107 | if ((r = sshbuf_get_string_direct(buf, &val, &len)) < 0) |
| 108 | return r; |
| 109 | if (valp != NULL) { |
| 110 | if ((*valp = malloc(len + 1)) == NULL) { |
| 111 | SSHBUF_DBG(("SSH_ERR_ALLOC_FAIL")); |
| 112 | return SSH_ERR_ALLOC_FAIL; |
| 113 | } |
djm@openbsd.org | a7f49dc | 2015-01-12 15:18:07 +0000 | [diff] [blame] | 114 | if (len != 0) |
| 115 | memcpy(*valp, val, len); |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 116 | (*valp)[len] = '\0'; |
| 117 | } |
| 118 | if (lenp != NULL) |
| 119 | *lenp = len; |
| 120 | return 0; |
| 121 | } |
| 122 | |
| 123 | int |
| 124 | sshbuf_get_string_direct(struct sshbuf *buf, const u_char **valp, size_t *lenp) |
| 125 | { |
| 126 | size_t len; |
| 127 | const u_char *p; |
| 128 | int r; |
| 129 | |
| 130 | if (valp != NULL) |
| 131 | *valp = NULL; |
| 132 | if (lenp != NULL) |
| 133 | *lenp = 0; |
| 134 | if ((r = sshbuf_peek_string_direct(buf, &p, &len)) < 0) |
| 135 | return r; |
mmcc@openbsd.org | 7d6c036 | 2015-10-20 23:24:25 +0000 | [diff] [blame] | 136 | if (valp != NULL) |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 137 | *valp = p; |
| 138 | if (lenp != NULL) |
| 139 | *lenp = len; |
| 140 | if (sshbuf_consume(buf, len + 4) != 0) { |
| 141 | /* Shouldn't happen */ |
| 142 | SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR")); |
| 143 | SSHBUF_ABORT(); |
| 144 | return SSH_ERR_INTERNAL_ERROR; |
| 145 | } |
| 146 | return 0; |
| 147 | } |
| 148 | |
| 149 | int |
| 150 | sshbuf_peek_string_direct(const struct sshbuf *buf, const u_char **valp, |
| 151 | size_t *lenp) |
| 152 | { |
| 153 | u_int32_t len; |
| 154 | const u_char *p = sshbuf_ptr(buf); |
| 155 | |
| 156 | if (valp != NULL) |
| 157 | *valp = NULL; |
| 158 | if (lenp != NULL) |
| 159 | *lenp = 0; |
| 160 | if (sshbuf_len(buf) < 4) { |
| 161 | SSHBUF_DBG(("SSH_ERR_MESSAGE_INCOMPLETE")); |
| 162 | return SSH_ERR_MESSAGE_INCOMPLETE; |
| 163 | } |
| 164 | len = PEEK_U32(p); |
| 165 | if (len > SSHBUF_SIZE_MAX - 4) { |
| 166 | SSHBUF_DBG(("SSH_ERR_STRING_TOO_LARGE")); |
| 167 | return SSH_ERR_STRING_TOO_LARGE; |
| 168 | } |
| 169 | if (sshbuf_len(buf) - 4 < len) { |
| 170 | SSHBUF_DBG(("SSH_ERR_MESSAGE_INCOMPLETE")); |
| 171 | return SSH_ERR_MESSAGE_INCOMPLETE; |
| 172 | } |
mmcc@openbsd.org | 7d6c036 | 2015-10-20 23:24:25 +0000 | [diff] [blame] | 173 | if (valp != NULL) |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 174 | *valp = p + 4; |
| 175 | if (lenp != NULL) |
| 176 | *lenp = len; |
| 177 | return 0; |
| 178 | } |
| 179 | |
| 180 | int |
| 181 | sshbuf_get_cstring(struct sshbuf *buf, char **valp, size_t *lenp) |
| 182 | { |
| 183 | size_t len; |
| 184 | const u_char *p, *z; |
| 185 | int r; |
| 186 | |
| 187 | if (valp != NULL) |
| 188 | *valp = NULL; |
| 189 | if (lenp != NULL) |
| 190 | *lenp = 0; |
| 191 | if ((r = sshbuf_peek_string_direct(buf, &p, &len)) != 0) |
| 192 | return r; |
| 193 | /* Allow a \0 only at the end of the string */ |
| 194 | if (len > 0 && |
| 195 | (z = memchr(p , '\0', len)) != NULL && z < p + len - 1) { |
| 196 | SSHBUF_DBG(("SSH_ERR_INVALID_FORMAT")); |
| 197 | return SSH_ERR_INVALID_FORMAT; |
| 198 | } |
| 199 | if ((r = sshbuf_skip_string(buf)) != 0) |
| 200 | return -1; |
| 201 | if (valp != NULL) { |
| 202 | if ((*valp = malloc(len + 1)) == NULL) { |
| 203 | SSHBUF_DBG(("SSH_ERR_ALLOC_FAIL")); |
| 204 | return SSH_ERR_ALLOC_FAIL; |
| 205 | } |
djm@openbsd.org | a7f49dc | 2015-01-12 15:18:07 +0000 | [diff] [blame] | 206 | if (len != 0) |
| 207 | memcpy(*valp, p, len); |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 208 | (*valp)[len] = '\0'; |
| 209 | } |
| 210 | if (lenp != NULL) |
| 211 | *lenp = (size_t)len; |
| 212 | return 0; |
| 213 | } |
| 214 | |
| 215 | int |
| 216 | sshbuf_get_stringb(struct sshbuf *buf, struct sshbuf *v) |
| 217 | { |
| 218 | u_int32_t len; |
| 219 | u_char *p; |
| 220 | int r; |
| 221 | |
| 222 | /* |
| 223 | * Use sshbuf_peek_string_direct() to figure out if there is |
| 224 | * a complete string in 'buf' and copy the string directly |
| 225 | * into 'v'. |
| 226 | */ |
| 227 | if ((r = sshbuf_peek_string_direct(buf, NULL, NULL)) != 0 || |
| 228 | (r = sshbuf_get_u32(buf, &len)) != 0 || |
| 229 | (r = sshbuf_reserve(v, len, &p)) != 0 || |
| 230 | (r = sshbuf_get(buf, p, len)) != 0) |
| 231 | return r; |
| 232 | return 0; |
| 233 | } |
| 234 | |
| 235 | int |
| 236 | sshbuf_put(struct sshbuf *buf, const void *v, size_t len) |
| 237 | { |
| 238 | u_char *p; |
| 239 | int r; |
| 240 | |
| 241 | if ((r = sshbuf_reserve(buf, len, &p)) < 0) |
| 242 | return r; |
djm@openbsd.org | a7f49dc | 2015-01-12 15:18:07 +0000 | [diff] [blame] | 243 | if (len != 0) |
| 244 | memcpy(p, v, len); |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 245 | return 0; |
| 246 | } |
| 247 | |
| 248 | int |
| 249 | sshbuf_putb(struct sshbuf *buf, const struct sshbuf *v) |
| 250 | { |
| 251 | return sshbuf_put(buf, sshbuf_ptr(v), sshbuf_len(v)); |
| 252 | } |
| 253 | |
| 254 | int |
| 255 | sshbuf_putf(struct sshbuf *buf, const char *fmt, ...) |
| 256 | { |
| 257 | va_list ap; |
| 258 | int r; |
| 259 | |
| 260 | va_start(ap, fmt); |
| 261 | r = sshbuf_putfv(buf, fmt, ap); |
| 262 | va_end(ap); |
| 263 | return r; |
| 264 | } |
| 265 | |
| 266 | int |
| 267 | sshbuf_putfv(struct sshbuf *buf, const char *fmt, va_list ap) |
| 268 | { |
| 269 | va_list ap2; |
| 270 | int r, len; |
| 271 | u_char *p; |
| 272 | |
Darren Tucker | 5abfb15 | 2016-07-15 14:48:30 +1000 | [diff] [blame^] | 273 | VA_COPY(ap2, ap); |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 274 | if ((len = vsnprintf(NULL, 0, fmt, ap2)) < 0) { |
| 275 | r = SSH_ERR_INVALID_ARGUMENT; |
| 276 | goto out; |
| 277 | } |
| 278 | if (len == 0) { |
| 279 | r = 0; |
| 280 | goto out; /* Nothing to do */ |
| 281 | } |
| 282 | va_end(ap2); |
Darren Tucker | 5abfb15 | 2016-07-15 14:48:30 +1000 | [diff] [blame^] | 283 | VA_COPY(ap2, ap); |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 284 | if ((r = sshbuf_reserve(buf, (size_t)len + 1, &p)) < 0) |
| 285 | goto out; |
| 286 | if ((r = vsnprintf((char *)p, len + 1, fmt, ap2)) != len) { |
| 287 | r = SSH_ERR_INTERNAL_ERROR; |
| 288 | goto out; /* Shouldn't happen */ |
| 289 | } |
| 290 | /* Consume terminating \0 */ |
| 291 | if ((r = sshbuf_consume_end(buf, 1)) != 0) |
| 292 | goto out; |
| 293 | r = 0; |
| 294 | out: |
| 295 | va_end(ap2); |
| 296 | return r; |
| 297 | } |
| 298 | |
| 299 | int |
| 300 | sshbuf_put_u64(struct sshbuf *buf, u_int64_t val) |
| 301 | { |
| 302 | u_char *p; |
| 303 | int r; |
| 304 | |
| 305 | if ((r = sshbuf_reserve(buf, 8, &p)) < 0) |
| 306 | return r; |
| 307 | POKE_U64(p, val); |
| 308 | return 0; |
| 309 | } |
| 310 | |
| 311 | int |
| 312 | sshbuf_put_u32(struct sshbuf *buf, u_int32_t val) |
| 313 | { |
| 314 | u_char *p; |
| 315 | int r; |
| 316 | |
| 317 | if ((r = sshbuf_reserve(buf, 4, &p)) < 0) |
| 318 | return r; |
| 319 | POKE_U32(p, val); |
| 320 | return 0; |
| 321 | } |
| 322 | |
| 323 | int |
| 324 | sshbuf_put_u16(struct sshbuf *buf, u_int16_t val) |
| 325 | { |
| 326 | u_char *p; |
| 327 | int r; |
| 328 | |
| 329 | if ((r = sshbuf_reserve(buf, 2, &p)) < 0) |
| 330 | return r; |
| 331 | POKE_U16(p, val); |
| 332 | return 0; |
| 333 | } |
| 334 | |
| 335 | int |
| 336 | sshbuf_put_u8(struct sshbuf *buf, u_char val) |
| 337 | { |
| 338 | u_char *p; |
| 339 | int r; |
| 340 | |
| 341 | if ((r = sshbuf_reserve(buf, 1, &p)) < 0) |
| 342 | return r; |
| 343 | p[0] = val; |
| 344 | return 0; |
| 345 | } |
| 346 | |
| 347 | int |
| 348 | sshbuf_put_string(struct sshbuf *buf, const void *v, size_t len) |
| 349 | { |
| 350 | u_char *d; |
| 351 | int r; |
| 352 | |
| 353 | if (len > SSHBUF_SIZE_MAX - 4) { |
| 354 | SSHBUF_DBG(("SSH_ERR_NO_BUFFER_SPACE")); |
| 355 | return SSH_ERR_NO_BUFFER_SPACE; |
| 356 | } |
| 357 | if ((r = sshbuf_reserve(buf, len + 4, &d)) < 0) |
| 358 | return r; |
| 359 | POKE_U32(d, len); |
djm@openbsd.org | a7f49dc | 2015-01-12 15:18:07 +0000 | [diff] [blame] | 360 | if (len != 0) |
| 361 | memcpy(d + 4, v, len); |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 362 | return 0; |
| 363 | } |
| 364 | |
| 365 | int |
| 366 | sshbuf_put_cstring(struct sshbuf *buf, const char *v) |
| 367 | { |
djm@openbsd.org | 74de254 | 2014-12-04 01:49:59 +0000 | [diff] [blame] | 368 | return sshbuf_put_string(buf, (u_char *)v, v == NULL ? 0 : strlen(v)); |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 369 | } |
| 370 | |
| 371 | int |
| 372 | sshbuf_put_stringb(struct sshbuf *buf, const struct sshbuf *v) |
| 373 | { |
| 374 | return sshbuf_put_string(buf, sshbuf_ptr(v), sshbuf_len(v)); |
| 375 | } |
| 376 | |
| 377 | int |
| 378 | sshbuf_froms(struct sshbuf *buf, struct sshbuf **bufp) |
| 379 | { |
| 380 | const u_char *p; |
| 381 | size_t len; |
| 382 | struct sshbuf *ret; |
| 383 | int r; |
| 384 | |
| 385 | if (buf == NULL || bufp == NULL) |
| 386 | return SSH_ERR_INVALID_ARGUMENT; |
| 387 | *bufp = NULL; |
| 388 | if ((r = sshbuf_peek_string_direct(buf, &p, &len)) != 0) |
| 389 | return r; |
| 390 | if ((ret = sshbuf_from(p, len)) == NULL) |
| 391 | return SSH_ERR_ALLOC_FAIL; |
| 392 | if ((r = sshbuf_consume(buf, len + 4)) != 0 || /* Shouldn't happen */ |
| 393 | (r = sshbuf_set_parent(ret, buf)) != 0) { |
| 394 | sshbuf_free(ret); |
| 395 | return r; |
| 396 | } |
| 397 | *bufp = ret; |
| 398 | return 0; |
| 399 | } |
| 400 | |
| 401 | int |
| 402 | sshbuf_put_bignum2_bytes(struct sshbuf *buf, const void *v, size_t len) |
| 403 | { |
| 404 | u_char *d; |
| 405 | const u_char *s = (const u_char *)v; |
| 406 | int r, prepend; |
| 407 | |
| 408 | if (len > SSHBUF_SIZE_MAX - 5) { |
| 409 | SSHBUF_DBG(("SSH_ERR_NO_BUFFER_SPACE")); |
| 410 | return SSH_ERR_NO_BUFFER_SPACE; |
| 411 | } |
| 412 | /* Skip leading zero bytes */ |
| 413 | for (; len > 0 && *s == 0; len--, s++) |
| 414 | ; |
| 415 | /* |
| 416 | * If most significant bit is set then prepend a zero byte to |
| 417 | * avoid interpretation as a negative number. |
| 418 | */ |
| 419 | prepend = len > 0 && (s[0] & 0x80) != 0; |
| 420 | if ((r = sshbuf_reserve(buf, len + 4 + prepend, &d)) < 0) |
| 421 | return r; |
| 422 | POKE_U32(d, len + prepend); |
| 423 | if (prepend) |
| 424 | d[4] = 0; |
djm@openbsd.org | a7f49dc | 2015-01-12 15:18:07 +0000 | [diff] [blame] | 425 | if (len != 0) |
| 426 | memcpy(d + 4 + prepend, s, len); |
Damien Miller | 05e82c3 | 2014-05-15 14:33:43 +1000 | [diff] [blame] | 427 | return 0; |
| 428 | } |
djm@openbsd.org | a165bab | 2015-01-14 15:02:39 +0000 | [diff] [blame] | 429 | |
| 430 | int |
| 431 | sshbuf_get_bignum2_bytes_direct(struct sshbuf *buf, |
| 432 | const u_char **valp, size_t *lenp) |
| 433 | { |
| 434 | const u_char *d; |
| 435 | size_t len, olen; |
| 436 | int r; |
| 437 | |
| 438 | if ((r = sshbuf_peek_string_direct(buf, &d, &olen)) < 0) |
| 439 | return r; |
| 440 | len = olen; |
| 441 | /* Refuse negative (MSB set) bignums */ |
| 442 | if ((len != 0 && (*d & 0x80) != 0)) |
| 443 | return SSH_ERR_BIGNUM_IS_NEGATIVE; |
| 444 | /* Refuse overlong bignums, allow prepended \0 to avoid MSB set */ |
| 445 | if (len > SSHBUF_MAX_BIGNUM + 1 || |
| 446 | (len == SSHBUF_MAX_BIGNUM + 1 && *d != 0)) |
| 447 | return SSH_ERR_BIGNUM_TOO_LARGE; |
| 448 | /* Trim leading zeros */ |
| 449 | while (len > 0 && *d == 0x00) { |
| 450 | d++; |
| 451 | len--; |
| 452 | } |
mmcc@openbsd.org | 7d6c036 | 2015-10-20 23:24:25 +0000 | [diff] [blame] | 453 | if (valp != NULL) |
djm@openbsd.org | a165bab | 2015-01-14 15:02:39 +0000 | [diff] [blame] | 454 | *valp = d; |
| 455 | if (lenp != NULL) |
| 456 | *lenp = len; |
| 457 | if (sshbuf_consume(buf, olen + 4) != 0) { |
| 458 | /* Shouldn't happen */ |
| 459 | SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR")); |
| 460 | SSHBUF_ABORT(); |
| 461 | return SSH_ERR_INTERNAL_ERROR; |
| 462 | } |
| 463 | return 0; |
| 464 | } |