1 /* $OpenBSD: sshbuf-getput-basic.c,v 1.13 2022/05/25 06:03:44 djm Exp $ */
3 * Copyright (c) 2011 Damien Miller
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.
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.
18 #define SSHBUF_INTERNAL
21 #include <sys/types.h>
35 sshbuf_get(struct sshbuf *buf, void *v, size_t len)
37 const u_char *p = sshbuf_ptr(buf);
40 if ((r = sshbuf_consume(buf, len)) < 0)
42 if (v != NULL && len != 0)
48 sshbuf_get_u64(struct sshbuf *buf, u_int64_t *valp)
50 const u_char *p = sshbuf_ptr(buf);
53 if ((r = sshbuf_consume(buf, 8)) < 0)
61 sshbuf_get_u32(struct sshbuf *buf, u_int32_t *valp)
63 const u_char *p = sshbuf_ptr(buf);
66 if ((r = sshbuf_consume(buf, 4)) < 0)
74 sshbuf_get_u16(struct sshbuf *buf, u_int16_t *valp)
76 const u_char *p = sshbuf_ptr(buf);
79 if ((r = sshbuf_consume(buf, 2)) < 0)
87 sshbuf_get_u8(struct sshbuf *buf, u_char *valp)
89 const u_char *p = sshbuf_ptr(buf);
92 if ((r = sshbuf_consume(buf, 1)) < 0)
100 check_offset(const struct sshbuf *buf, int wr, size_t offset, size_t len)
102 if (sshbuf_ptr(buf) == NULL) /* calls sshbuf_check_sanity() */
103 return SSH_ERR_INTERNAL_ERROR;
104 if (offset >= SIZE_MAX - len)
105 return SSH_ERR_INVALID_ARGUMENT;
106 if (offset + len > sshbuf_len(buf)) {
108 SSH_ERR_NO_BUFFER_SPACE : SSH_ERR_MESSAGE_INCOMPLETE;
114 check_roffset(const struct sshbuf *buf, size_t offset, size_t len,
120 if ((r = check_offset(buf, 0, offset, len)) != 0)
122 *p = sshbuf_ptr(buf) + offset;
127 sshbuf_peek_u64(const struct sshbuf *buf, size_t offset, u_int64_t *valp)
129 const u_char *p = NULL;
134 if ((r = check_roffset(buf, offset, 8, &p)) != 0)
142 sshbuf_peek_u32(const struct sshbuf *buf, size_t offset, u_int32_t *valp)
144 const u_char *p = NULL;
149 if ((r = check_roffset(buf, offset, 4, &p)) != 0)
157 sshbuf_peek_u16(const struct sshbuf *buf, size_t offset, u_int16_t *valp)
159 const u_char *p = NULL;
164 if ((r = check_roffset(buf, offset, 2, &p)) != 0)
172 sshbuf_peek_u8(const struct sshbuf *buf, size_t offset, u_char *valp)
174 const u_char *p = NULL;
179 if ((r = check_roffset(buf, offset, 1, &p)) != 0)
187 sshbuf_get_string(struct sshbuf *buf, u_char **valp, size_t *lenp)
197 if ((r = sshbuf_get_string_direct(buf, &val, &len)) < 0)
200 if ((*valp = malloc(len + 1)) == NULL) {
201 SSHBUF_DBG(("SSH_ERR_ALLOC_FAIL"));
202 return SSH_ERR_ALLOC_FAIL;
205 memcpy(*valp, val, len);
214 sshbuf_get_string_direct(struct sshbuf *buf, const u_char **valp, size_t *lenp)
224 if ((r = sshbuf_peek_string_direct(buf, &p, &len)) < 0)
230 if (sshbuf_consume(buf, len + 4) != 0) {
231 /* Shouldn't happen */
232 SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR"));
234 return SSH_ERR_INTERNAL_ERROR;
240 sshbuf_peek_string_direct(const struct sshbuf *buf, const u_char **valp,
244 const u_char *p = sshbuf_ptr(buf);
250 if (sshbuf_len(buf) < 4) {
251 SSHBUF_DBG(("SSH_ERR_MESSAGE_INCOMPLETE"));
252 return SSH_ERR_MESSAGE_INCOMPLETE;
255 if (len > SSHBUF_SIZE_MAX - 4) {
256 SSHBUF_DBG(("SSH_ERR_STRING_TOO_LARGE"));
257 return SSH_ERR_STRING_TOO_LARGE;
259 if (sshbuf_len(buf) - 4 < len) {
260 SSHBUF_DBG(("SSH_ERR_MESSAGE_INCOMPLETE"));
261 return SSH_ERR_MESSAGE_INCOMPLETE;
271 sshbuf_get_cstring(struct sshbuf *buf, char **valp, size_t *lenp)
281 if ((r = sshbuf_peek_string_direct(buf, &p, &len)) != 0)
283 /* Allow a \0 only at the end of the string */
285 (z = memchr(p , '\0', len)) != NULL && z < p + len - 1) {
286 SSHBUF_DBG(("SSH_ERR_INVALID_FORMAT"));
287 return SSH_ERR_INVALID_FORMAT;
289 if ((r = sshbuf_skip_string(buf)) != 0)
292 if ((*valp = malloc(len + 1)) == NULL) {
293 SSHBUF_DBG(("SSH_ERR_ALLOC_FAIL"));
294 return SSH_ERR_ALLOC_FAIL;
297 memcpy(*valp, p, len);
306 sshbuf_get_stringb(struct sshbuf *buf, struct sshbuf *v)
313 * Use sshbuf_peek_string_direct() to figure out if there is
314 * a complete string in 'buf' and copy the string directly
317 if ((r = sshbuf_peek_string_direct(buf, NULL, NULL)) != 0 ||
318 (r = sshbuf_get_u32(buf, &len)) != 0 ||
319 (r = sshbuf_reserve(v, len, &p)) != 0 ||
320 (r = sshbuf_get(buf, p, len)) != 0)
326 sshbuf_put(struct sshbuf *buf, const void *v, size_t len)
331 if ((r = sshbuf_reserve(buf, len, &p)) < 0)
339 sshbuf_putb(struct sshbuf *buf, const struct sshbuf *v)
343 return sshbuf_put(buf, sshbuf_ptr(v), sshbuf_len(v));
347 sshbuf_putf(struct sshbuf *buf, const char *fmt, ...)
353 r = sshbuf_putfv(buf, fmt, ap);
359 sshbuf_putfv(struct sshbuf *buf, const char *fmt, va_list ap)
366 if ((len = vsnprintf(NULL, 0, fmt, ap2)) < 0) {
367 r = SSH_ERR_INVALID_ARGUMENT;
372 goto out; /* Nothing to do */
376 if ((r = sshbuf_reserve(buf, (size_t)len + 1, &p)) < 0)
378 if ((r = vsnprintf((char *)p, len + 1, fmt, ap2)) != len) {
379 r = SSH_ERR_INTERNAL_ERROR;
380 goto out; /* Shouldn't happen */
382 /* Consume terminating \0 */
383 if ((r = sshbuf_consume_end(buf, 1)) != 0)
392 sshbuf_put_u64(struct sshbuf *buf, u_int64_t val)
397 if ((r = sshbuf_reserve(buf, 8, &p)) < 0)
404 sshbuf_put_u32(struct sshbuf *buf, u_int32_t val)
409 if ((r = sshbuf_reserve(buf, 4, &p)) < 0)
416 sshbuf_put_u16(struct sshbuf *buf, u_int16_t val)
421 if ((r = sshbuf_reserve(buf, 2, &p)) < 0)
428 sshbuf_put_u8(struct sshbuf *buf, u_char val)
433 if ((r = sshbuf_reserve(buf, 1, &p)) < 0)
440 check_woffset(struct sshbuf *buf, size_t offset, size_t len, u_char **p)
445 if ((r = check_offset(buf, 1, offset, len)) != 0)
447 if (sshbuf_mutable_ptr(buf) == NULL)
448 return SSH_ERR_BUFFER_READ_ONLY;
449 *p = sshbuf_mutable_ptr(buf) + offset;
454 sshbuf_poke_u64(struct sshbuf *buf, size_t offset, u_int64_t val)
459 if ((r = check_woffset(buf, offset, 8, &p)) != 0)
466 sshbuf_poke_u32(struct sshbuf *buf, size_t offset, u_int32_t val)
471 if ((r = check_woffset(buf, offset, 4, &p)) != 0)
478 sshbuf_poke_u16(struct sshbuf *buf, size_t offset, u_int16_t val)
483 if ((r = check_woffset(buf, offset, 2, &p)) != 0)
490 sshbuf_poke_u8(struct sshbuf *buf, size_t offset, u_char val)
495 if ((r = check_woffset(buf, offset, 1, &p)) != 0)
502 sshbuf_poke(struct sshbuf *buf, size_t offset, void *v, size_t len)
507 if ((r = check_woffset(buf, offset, len, &p)) != 0)
514 sshbuf_put_string(struct sshbuf *buf, const void *v, size_t len)
519 if (len > SSHBUF_SIZE_MAX - 4) {
520 SSHBUF_DBG(("SSH_ERR_NO_BUFFER_SPACE"));
521 return SSH_ERR_NO_BUFFER_SPACE;
523 if ((r = sshbuf_reserve(buf, len + 4, &d)) < 0)
527 memcpy(d + 4, v, len);
532 sshbuf_put_cstring(struct sshbuf *buf, const char *v)
534 return sshbuf_put_string(buf, v, v == NULL ? 0 : strlen(v));
538 sshbuf_put_stringb(struct sshbuf *buf, const struct sshbuf *v)
541 return sshbuf_put_string(buf, NULL, 0);
543 return sshbuf_put_string(buf, sshbuf_ptr(v), sshbuf_len(v));
547 sshbuf_froms(struct sshbuf *buf, struct sshbuf **bufp)
554 if (buf == NULL || bufp == NULL)
555 return SSH_ERR_INVALID_ARGUMENT;
557 if ((r = sshbuf_peek_string_direct(buf, &p, &len)) != 0)
559 if ((ret = sshbuf_from(p, len)) == NULL)
560 return SSH_ERR_ALLOC_FAIL;
561 if ((r = sshbuf_consume(buf, len + 4)) != 0 || /* Shouldn't happen */
562 (r = sshbuf_set_parent(ret, buf)) != 0) {
571 sshbuf_put_bignum2_bytes(struct sshbuf *buf, const void *v, size_t len)
574 const u_char *s = (const u_char *)v;
577 if (len > SSHBUF_SIZE_MAX - 5) {
578 SSHBUF_DBG(("SSH_ERR_NO_BUFFER_SPACE"));
579 return SSH_ERR_NO_BUFFER_SPACE;
581 /* Skip leading zero bytes */
582 for (; len > 0 && *s == 0; len--, s++)
585 * If most significant bit is set then prepend a zero byte to
586 * avoid interpretation as a negative number.
588 prepend = len > 0 && (s[0] & 0x80) != 0;
589 if ((r = sshbuf_reserve(buf, len + 4 + prepend, &d)) < 0)
591 POKE_U32(d, len + prepend);
595 memcpy(d + 4 + prepend, s, len);
600 sshbuf_get_bignum2_bytes_direct(struct sshbuf *buf,
601 const u_char **valp, size_t *lenp)
607 if ((r = sshbuf_peek_string_direct(buf, &d, &olen)) < 0)
610 /* Refuse negative (MSB set) bignums */
611 if ((len != 0 && (*d & 0x80) != 0))
612 return SSH_ERR_BIGNUM_IS_NEGATIVE;
613 /* Refuse overlong bignums, allow prepended \0 to avoid MSB set */
614 if (len > SSHBUF_MAX_BIGNUM + 1 ||
615 (len == SSHBUF_MAX_BIGNUM + 1 && *d != 0))
616 return SSH_ERR_BIGNUM_TOO_LARGE;
617 /* Trim leading zeros */
618 while (len > 0 && *d == 0x00) {
626 if (sshbuf_consume(buf, olen + 4) != 0) {
627 /* Shouldn't happen */
628 SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR"));
630 return SSH_ERR_INTERNAL_ERROR;