/src/openssh/sshbuf-misc.c

Source
/*  $OpenBSD: sshbuf-misc.c,v 1.22 2025/09/04 00:32:31 djm Exp $  */
/*
 * Copyright (c) 2011 Damien Miller
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "includes.h"

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <limits.h>
#include <string.h>
#include <resolv.h>
#include <ctype.h>
#include <unistd.h>

#include "ssherr.h"
#define SSHBUF_INTERNAL
#include "sshbuf.h"

void
sshbuf_dump_data(const void *s, size_t len, FILE *f)
{
  size_t i, j;
  const u_char *p = (const u_char *)s;

  for (i = 0; i < len; i += 16) {
    fprintf(f, "%.4zu: ", i);
    for (j = i; j < i + 16; j++) {
      if (j < len)
        fprintf(f, "%02x ", p[j]);
      else
        fprintf(f, "   ");
    }
    fprintf(f, " ");
    for (j = i; j < i + 16; j++) {
      if (j < len) {
        if  (isascii(p[j]) && isprint(p[j]))
          fprintf(f, "%c", p[j]);
        else
          fprintf(f, ".");
      }
    }
    fprintf(f, "\n");
  }
}

void
sshbuf_dump(const struct sshbuf *buf, FILE *f)
{
  fprintf(f, "buffer len = %zu\n", sshbuf_len(buf));
  sshbuf_dump_data(sshbuf_ptr(buf), sshbuf_len(buf), f);
}

char *
sshbuf_dtob16(const struct sshbuf *buf)
{
  size_t i, j, len = sshbuf_len(buf);
  const u_char *p = sshbuf_ptr(buf);
  char *ret;
  const char hex[] = "0123456789abcdef";

  if (len == 0)
    return strdup("");
  if (SIZE_MAX / 2 <= len || (ret = malloc(len * 2 + 1)) == NULL)
    return NULL;
  for (i = j = 0; i < len; i++) {
    ret[j++] = hex[(p[i] >> 4) & 0xf];
    ret[j++] = hex[p[i] & 0xf];
  }
  ret[j] = '\0';
  return ret;
}

static int
b16tod(const char v)
{
  if (v >= '0' && v <= '9')
    return v - '0';
  if (v >= 'a' && v <= 'f')
    return 10 + v - 'a';
  if (v >= 'A' && v <= 'A')
    return 10 + v - 'A';
  return -1;
}

struct sshbuf *
sshbuf_b16tod(const char *b16)
{
  struct sshbuf *ret;
  size_t o;
  int r, v1, v2;

  if ((ret = sshbuf_new()) == NULL)
    return NULL;
  for (o = 0; b16[o] != '\0'; o += 2) {
    if ((v1 = b16tod(b16[o])) == -1 ||
        (v2 = b16tod(b16[o + 1])) == -1) {
      sshbuf_free(ret);
      return NULL;
    }
    if ((r = sshbuf_put_u8(ret, (u_char)((v1 << 4) | v2))) != 0) {
      sshbuf_free(ret);
      return NULL;
    }
  }
  /* success */
  return ret;
}

int
sshbuf_dtob64(const struct sshbuf *d, struct sshbuf *b64, int wrap)
{
  size_t i, slen = 0;
  char *s = NULL;
  int r;

  if (d == NULL || b64 == NULL || sshbuf_len(d) >= SIZE_MAX / 2)
    return SSH_ERR_INVALID_ARGUMENT;
  if (sshbuf_len(d) == 0)
    return 0;
  slen = ((sshbuf_len(d) + 2) / 3) * 4 + 1;
  if ((s = malloc(slen)) == NULL)
    return SSH_ERR_ALLOC_FAIL;
  if (b64_ntop(sshbuf_ptr(d), sshbuf_len(d), s, slen) == -1) {
    r = SSH_ERR_INTERNAL_ERROR;
    goto fail;
  }
  if (wrap) {
    for (i = 0; s[i] != '\0'; i++) {
      if ((r = sshbuf_put_u8(b64, s[i])) != 0)
        goto fail;
      if (i % 70 == 69 && (r = sshbuf_put_u8(b64, '\n')) != 0)
        goto fail;
    }
    if ((i - 1) % 70 != 69 && (r = sshbuf_put_u8(b64, '\n')) != 0)
      goto fail;
  } else {
    if ((r = sshbuf_put(b64, s, strlen(s))) != 0)
      goto fail;
  }
  /* Success */
  r = 0;
 fail:
  freezero(s, slen);
  return r;
}

char *
sshbuf_dtob64_string(const struct sshbuf *buf, int wrap)
{
  struct sshbuf *tmp;
  char *ret;

  if ((tmp = sshbuf_new()) == NULL)
    return NULL;
  if (sshbuf_dtob64(buf, tmp, wrap) != 0) {
    sshbuf_free(tmp);
    return NULL;
  }
  ret = sshbuf_dup_string(tmp);
  sshbuf_free(tmp);
  return ret;
}

int
sshbuf_b64tod(struct sshbuf *buf, const char *b64)
{
  size_t plen = strlen(b64);
  int nlen, r;
  u_char *p;

  if (plen == 0)
    return 0;
  if ((p = malloc(plen)) == NULL)
    return SSH_ERR_ALLOC_FAIL;
  if ((nlen = b64_pton(b64, p, plen)) < 0) {
    freezero(p, plen);
    return SSH_ERR_INVALID_FORMAT;
  }
  if ((r = sshbuf_put(buf, p, nlen)) < 0) {
    freezero(p, plen);
    return r;
  }
  freezero(p, plen);
  return 0;
}

int
sshbuf_dtourlb64(const struct sshbuf *d, struct sshbuf *b64, int wrap)
{
  int r = SSH_ERR_INTERNAL_ERROR;
  u_char *p;
  struct sshbuf *b = NULL;
  size_t i, l;

  if (sshbuf_len(d) == 0)
    return 0;

  if ((b = sshbuf_new()) == NULL)
    return SSH_ERR_ALLOC_FAIL;
  /* Encode using regular base64; we'll transform it once done */
  if ((r = sshbuf_dtob64(d, b, wrap)) != 0)
    goto out;
  /* remove padding from end of encoded string*/
  for (;;) {
    l = sshbuf_len(b);
    if (l <= 1 || sshbuf_ptr(b) == NULL) {
      r = SSH_ERR_INTERNAL_ERROR;
      goto out;
    }
    if (sshbuf_ptr(b)[l - 1] != '=')
      break;
    if ((r = sshbuf_consume_end(b, 1)) != 0)
      goto out;
  }
  /* Replace characters with rfc4648 equivalents */
  l = sshbuf_len(b);
  if ((p = sshbuf_mutable_ptr(b)) == NULL) {
    r = SSH_ERR_INTERNAL_ERROR;
    goto out;
  }
  for (i = 0; i < l; i++) {
    if (p[i] == '+')
      p[i] = '-';
    else if (p[i] == '/')
      p[i] = '_';
  }
  r = sshbuf_putb(b64, b);
 out:
  sshbuf_free(b);
  return r;
}

char *
sshbuf_dup_string(struct sshbuf *buf)
{
  const u_char *p = NULL, *s = sshbuf_ptr(buf);
  size_t l = sshbuf_len(buf);
  char *r;

  if (s == NULL || l >= SIZE_MAX)
    return NULL;
  /* accept a nul only as the last character in the buffer */
  if (l > 0 && (p = memchr(s, '\0', l)) != NULL) {
    if (p != s + l - 1)
      return NULL;
    l--; /* the nul is put back below */
  }
  if ((r = malloc(l + 1)) == NULL)
    return NULL;
  if (l > 0)
    memcpy(r, s, l);
  r[l] = '\0';
  return r;
}

int
sshbuf_cmp(const struct sshbuf *b, size_t offset,
    const void *s, size_t len)
{
  if (sshbuf_ptr(b) == NULL)
    return SSH_ERR_INTERNAL_ERROR;
  if (offset > SSHBUF_SIZE_MAX || len > SSHBUF_SIZE_MAX || len == 0)
    return SSH_ERR_INVALID_ARGUMENT;
  if (offset + len > sshbuf_len(b))
    return SSH_ERR_MESSAGE_INCOMPLETE;
  if (timingsafe_bcmp(sshbuf_ptr(b) + offset, s, len) != 0)
    return SSH_ERR_INVALID_FORMAT;
  return 0;
}

int
sshbuf_equals(const struct sshbuf *a, const struct sshbuf *b)
{
  if (sshbuf_ptr(a) == NULL || sshbuf_ptr(b) == NULL)
    return SSH_ERR_INTERNAL_ERROR;
  if (sshbuf_len(a) != sshbuf_len(b))
    return SSH_ERR_MESSAGE_INCOMPLETE;
  if (sshbuf_len(a) == 0)
    return 0;
  if (memcmp(sshbuf_ptr(a), sshbuf_ptr(b), sshbuf_len(a)) != 0)
    return SSH_ERR_INVALID_FORMAT;
  return 0;
}

int
sshbuf_find(const struct sshbuf *b, size_t start_offset,
    const void *s, size_t len, size_t *offsetp)
{
  void *p;

  if (offsetp != NULL)
    *offsetp = 0;
  if (sshbuf_ptr(b) == NULL)
    return SSH_ERR_INTERNAL_ERROR;
  if (start_offset > SSHBUF_SIZE_MAX || len > SSHBUF_SIZE_MAX || len == 0)
    return SSH_ERR_INVALID_ARGUMENT;
  if (start_offset > sshbuf_len(b) || start_offset + len > sshbuf_len(b))
    return SSH_ERR_MESSAGE_INCOMPLETE;
  if ((p = memmem(sshbuf_ptr(b) + start_offset,
      sshbuf_len(b) - start_offset, s, len)) == NULL)
    return SSH_ERR_INVALID_FORMAT;
  if (offsetp != NULL)
    *offsetp = (const u_char *)p - sshbuf_ptr(b);
  return 0;
}

int
sshbuf_read(int fd, struct sshbuf *buf, size_t maxlen, size_t *rlen)
{
  int r, oerrno;
  size_t adjust;
  ssize_t rr;
  u_char *d;

  if (rlen != NULL)
    *rlen = 0;
  if ((r = sshbuf_reserve(buf, maxlen, &d)) != 0)
    return r;
  rr = read(fd, d, maxlen);
  oerrno = errno;

  /* Adjust the buffer to include only what was actually read */
  if ((adjust = maxlen - (rr > 0 ? rr : 0)) != 0) {
    if ((r = sshbuf_consume_end(buf, adjust)) != 0) {
      /* avoid returning uninitialised data to caller */
      memset(d + rr, '\0', adjust);
      return SSH_ERR_INTERNAL_ERROR; /* shouldn't happen */
    }
  }
  if (rr < 0) {
    errno = oerrno;
    return SSH_ERR_SYSTEM_ERROR;
  } else if (rr == 0) {
    errno = EPIPE;
    return SSH_ERR_SYSTEM_ERROR;
  }
  /* success */
  if (rlen != NULL)
    *rlen = (size_t)rr;
  return 0;
}

Coverage Report

Created: 2025-10-10 06:39

Line	Count	Source
1		/* $OpenBSD: sshbuf-misc.c,v 1.22 2025/09/04 00:32:31 djm Exp $ */
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
18		#include "includes.h"
19
20		#include <sys/types.h>
21		#include <sys/socket.h>
22		#include <netinet/in.h>
23		#include <errno.h>
24		#include <stdlib.h>
25		#include <stdint.h>
26		#include <stdio.h>
27		#include <limits.h>
28		#include <string.h>
29		#include <resolv.h>
30		#include <ctype.h>
31		#include <unistd.h>
32
33		#include "ssherr.h"
34		#define SSHBUF_INTERNAL
35		#include "sshbuf.h"
36
37		void
38		sshbuf_dump_data(const void s, size_t len, FILE f)
39	0	{
40	0	size_t i, j;
41	0	const u_char p = (const u_char )s;
42
43	0	for (i = 0; i < len; i += 16) {
44	0	fprintf(f, "%.4zu: ", i);
45	0	for (j = i; j < i + 16; j++) {
46	0	if (j < len)
47	0	fprintf(f, "%02x ", p[j]);
48	0	else
49	0	fprintf(f, " ");
50	0	}
51	0	fprintf(f, " ");
52	0	for (j = i; j < i + 16; j++) {
53	0	if (j < len) {
54	0	if (isascii(p[j]) && isprint(p[j]))
55	0	fprintf(f, "%c", p[j]);
56	0	else
57	0	fprintf(f, ".");
58	0	}
59	0	}
60	0	fprintf(f, "\n");
61	0	}
62	0	}
63
64		void
65		sshbuf_dump(const struct sshbuf buf, FILE f)
66	0	{
67	0	fprintf(f, "buffer len = %zu\n", sshbuf_len(buf));
68	0	sshbuf_dump_data(sshbuf_ptr(buf), sshbuf_len(buf), f);
69	0	}
70
71		char *
72		sshbuf_dtob16(const struct sshbuf *buf)
73	0	{
74	0	size_t i, j, len = sshbuf_len(buf);
75	0	const u_char *p = sshbuf_ptr(buf);
76	0	char *ret;
77	0	const char hex[] = "0123456789abcdef";
78
79	0	if (len == 0)
80	0	return strdup("");
81	0	if (SIZE_MAX / 2 <= len \|\| (ret = malloc(len * 2 + 1)) == NULL)
82	0	return NULL;
83	0	for (i = j = 0; i < len; i++) {
84	0	ret[j++] = hex[(p[i] >> 4) & 0xf];
85	0	ret[j++] = hex[p[i] & 0xf];
86	0	}
87	0	ret[j] = '\0';
88	0	return ret;
89	0	}
90
91		static int
92		b16tod(const char v)
93	0	{
94	0	if (v >= '0' && v <= '9')
95	0	return v - '0';
96	0	if (v >= 'a' && v <= 'f')
97	0	return 10 + v - 'a';
98	0	if (v >= 'A' && v <= 'A')
99	0	return 10 + v - 'A';
100	0	return -1;
101	0	}
102
103		struct sshbuf *
104		sshbuf_b16tod(const char *b16)
105	0	{
106	0	struct sshbuf *ret;
107	0	size_t o;
108	0	int r, v1, v2;
109
110	0	if ((ret = sshbuf_new()) == NULL)
111	0	return NULL;
112	0	for (o = 0; b16[o] != '\0'; o += 2) {
113	0	if ((v1 = b16tod(b16[o])) == -1 \|\|
114	0	(v2 = b16tod(b16[o + 1])) == -1) {
115	0	sshbuf_free(ret);
116	0	return NULL;
117	0	}
118	0	if ((r = sshbuf_put_u8(ret, (u_char)((v1 << 4) \| v2))) != 0) {
119	0	sshbuf_free(ret);
120	0	return NULL;
121	0	}
122	0	}
123		/* success */
124	0	return ret;
125	0	}
126
127		int
128		sshbuf_dtob64(const struct sshbuf d, struct sshbuf b64, int wrap)
129	0	{
130	0	size_t i, slen = 0;
131	0	char *s = NULL;
132	0	int r;
133
134	0	if (d == NULL \|\| b64 == NULL \|\| sshbuf_len(d) >= SIZE_MAX / 2)
135	0	return SSH_ERR_INVALID_ARGUMENT;
136	0	if (sshbuf_len(d) == 0)
137	0	return 0;
138	0	slen = ((sshbuf_len(d) + 2) / 3) * 4 + 1;
139	0	if ((s = malloc(slen)) == NULL)
140	0	return SSH_ERR_ALLOC_FAIL;
141	0	if (b64_ntop(sshbuf_ptr(d), sshbuf_len(d), s, slen) == -1) {
142	0	r = SSH_ERR_INTERNAL_ERROR;
143	0	goto fail;
144	0	}
145	0	if (wrap) {
146	0	for (i = 0; s[i] != '\0'; i++) {
147	0	if ((r = sshbuf_put_u8(b64, s[i])) != 0)
148	0	goto fail;
149	0	if (i % 70 == 69 && (r = sshbuf_put_u8(b64, '\n')) != 0)
150	0	goto fail;
151	0	}
152	0	if ((i - 1) % 70 != 69 && (r = sshbuf_put_u8(b64, '\n')) != 0)
153	0	goto fail;
154	0	} else {
155	0	if ((r = sshbuf_put(b64, s, strlen(s))) != 0)
156	0	goto fail;
157	0	}
158		/* Success */
159	0	r = 0;
160	0	fail:
161	0	freezero(s, slen);
162	0	return r;
163	0	}
164
165		char *
166		sshbuf_dtob64_string(const struct sshbuf *buf, int wrap)
167	0	{
168	0	struct sshbuf *tmp;
169	0	char *ret;
170
171	0	if ((tmp = sshbuf_new()) == NULL)
172	0	return NULL;
173	0	if (sshbuf_dtob64(buf, tmp, wrap) != 0) {
174	0	sshbuf_free(tmp);
175	0	return NULL;
176	0	}
177	0	ret = sshbuf_dup_string(tmp);
178	0	sshbuf_free(tmp);
179	0	return ret;
180	0	}
181
182		int
183		sshbuf_b64tod(struct sshbuf buf, const char b64)
184	6	{
185	6	size_t plen = strlen(b64);
186	6	int nlen, r;
187	6	u_char *p;
188
189	6	if (plen == 0)
190	0	return 0;
191	6	if ((p = malloc(plen)) == NULL)
192	0	return SSH_ERR_ALLOC_FAIL;
193	6	if ((nlen = b64_pton(b64, p, plen)) < 0) {
194	0	freezero(p, plen);
195	0	return SSH_ERR_INVALID_FORMAT;
196	0	}
197	6	if ((r = sshbuf_put(buf, p, nlen)) < 0) {
198	0	freezero(p, plen);
199	0	return r;
200	0	}
201	6	freezero(p, plen);
202	6	return 0;
203	6	}
204
205		int
206		sshbuf_dtourlb64(const struct sshbuf d, struct sshbuf b64, int wrap)
207	0	{
208	0	int r = SSH_ERR_INTERNAL_ERROR;
209	0	u_char *p;
210	0	struct sshbuf *b = NULL;
211	0	size_t i, l;
212
213	0	if (sshbuf_len(d) == 0)
214	0	return 0;
215
216	0	if ((b = sshbuf_new()) == NULL)
217	0	return SSH_ERR_ALLOC_FAIL;
218		/* Encode using regular base64; we'll transform it once done */
219	0	if ((r = sshbuf_dtob64(d, b, wrap)) != 0)
220	0	goto out;
221		/* remove padding from end of encoded string*/
222	0	for (;;) {
223	0	l = sshbuf_len(b);
224	0	if (l <= 1 \|\| sshbuf_ptr(b) == NULL) {
225	0	r = SSH_ERR_INTERNAL_ERROR;
226	0	goto out;
227	0	}
228	0	if (sshbuf_ptr(b)[l - 1] != '=')
229	0	break;
230	0	if ((r = sshbuf_consume_end(b, 1)) != 0)
231	0	goto out;
232	0	}
233		/* Replace characters with rfc4648 equivalents */
234	0	l = sshbuf_len(b);
235	0	if ((p = sshbuf_mutable_ptr(b)) == NULL) {
236	0	r = SSH_ERR_INTERNAL_ERROR;
237	0	goto out;
238	0	}
239	0	for (i = 0; i < l; i++) {
240	0	if (p[i] == '+')
241	0	p[i] = '-';
242	0	else if (p[i] == '/')
243	0	p[i] = '_';
244	0	}
245	0	r = sshbuf_putb(b64, b);
246	0	out:
247	0	sshbuf_free(b);
248	0	return r;
249	0	}
250
251		char *
252		sshbuf_dup_string(struct sshbuf *buf)
253	225k	{
254	225k	const u_char p = NULL, s = sshbuf_ptr(buf);
255	225k	size_t l = sshbuf_len(buf);
256	225k	char *r;
257
258	225k	if (s == NULL \|\| l >= SIZE_MAX)
259	0	return NULL;
260		/* accept a nul only as the last character in the buffer */
261	225k	if (l > 0 && (p = memchr(s, '\0', l)) != NULL) {
262	555	if (p != s + l - 1)
263	195	return NULL;
264	360	l--; /* the nul is put back below */
265	360	}
266	225k	if ((r = malloc(l + 1)) == NULL)
267	0	return NULL;
268	225k	if (l > 0)
269	225k	memcpy(r, s, l);
270	225k	r[l] = '\0';
271	225k	return r;
272	225k	}
273
274		int
275		sshbuf_cmp(const struct sshbuf *b, size_t offset,
276		const void *s, size_t len)
277	0	{
278	0	if (sshbuf_ptr(b) == NULL)
279	0	return SSH_ERR_INTERNAL_ERROR;
280	0	if (offset > SSHBUF_SIZE_MAX \|\| len > SSHBUF_SIZE_MAX \|\| len == 0)
281	0	return SSH_ERR_INVALID_ARGUMENT;
282	0	if (offset + len > sshbuf_len(b))
283	0	return SSH_ERR_MESSAGE_INCOMPLETE;
284	0	if (timingsafe_bcmp(sshbuf_ptr(b) + offset, s, len) != 0)
285	0	return SSH_ERR_INVALID_FORMAT;
286	0	return 0;
287	0	}
288
289		int
290		sshbuf_equals(const struct sshbuf a, const struct sshbuf b)
291	0	{
292	0	if (sshbuf_ptr(a) == NULL \|\| sshbuf_ptr(b) == NULL)
293	0	return SSH_ERR_INTERNAL_ERROR;
294	0	if (sshbuf_len(a) != sshbuf_len(b))
295	0	return SSH_ERR_MESSAGE_INCOMPLETE;
296	0	if (sshbuf_len(a) == 0)
297	0	return 0;
298	0	if (memcmp(sshbuf_ptr(a), sshbuf_ptr(b), sshbuf_len(a)) != 0)
299	0	return SSH_ERR_INVALID_FORMAT;
300	0	return 0;
301	0	}
302
303		int
304		sshbuf_find(const struct sshbuf *b, size_t start_offset,
305		const void s, size_t len, size_t offsetp)
306	0	{
307	0	void *p;
308
309	0	if (offsetp != NULL)
310	0	*offsetp = 0;
311	0	if (sshbuf_ptr(b) == NULL)
312	0	return SSH_ERR_INTERNAL_ERROR;
313	0	if (start_offset > SSHBUF_SIZE_MAX \|\| len > SSHBUF_SIZE_MAX \|\| len == 0)
314	0	return SSH_ERR_INVALID_ARGUMENT;
315	0	if (start_offset > sshbuf_len(b) \|\| start_offset + len > sshbuf_len(b))
316	0	return SSH_ERR_MESSAGE_INCOMPLETE;
317	0	if ((p = memmem(sshbuf_ptr(b) + start_offset,
318	0	sshbuf_len(b) - start_offset, s, len)) == NULL)
319	0	return SSH_ERR_INVALID_FORMAT;
320	0	if (offsetp != NULL)
321	0	offsetp = (const u_char )p - sshbuf_ptr(b);
322	0	return 0;
323	0	}
324
325		int
326		sshbuf_read(int fd, struct sshbuf buf, size_t maxlen, size_t rlen)
327	0	{
328	0	int r, oerrno;
329	0	size_t adjust;
330	0	ssize_t rr;
331	0	u_char *d;
332
333	0	if (rlen != NULL)
334	0	*rlen = 0;
335	0	if ((r = sshbuf_reserve(buf, maxlen, &d)) != 0)
336	0	return r;
337	0	rr = read(fd, d, maxlen);
338	0	oerrno = errno;
339
340		/* Adjust the buffer to include only what was actually read */
341	0	if ((adjust = maxlen - (rr > 0 ? rr : 0)) != 0) {
342	0	if ((r = sshbuf_consume_end(buf, adjust)) != 0) {
343		/* avoid returning uninitialised data to caller */
344	0	memset(d + rr, '\0', adjust);
345	0	return SSH_ERR_INTERNAL_ERROR; /* shouldn't happen */
346	0	}
347	0	}
348	0	if (rr < 0) {
349	0	errno = oerrno;
350	0	return SSH_ERR_SYSTEM_ERROR;
351	0	} else if (rr == 0) {
352	0	errno = EPIPE;
353	0	return SSH_ERR_SYSTEM_ERROR;
354	0	}
355		/* success */
356	0	if (rlen != NULL)
357	0	*rlen = (size_t)rr;
358	0	return 0;
359	0	}