Annotation of src/usr.bin/ssh/sshbuf-misc.c, Revision 1.17
1.17 ! djm 1: /* $OpenBSD: sshbuf-misc.c,v 1.16 2020/06/22 05:54:10 djm Exp $ */
1.1 djm 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 <sys/types.h>
19: #include <sys/socket.h>
20: #include <netinet/in.h>
21: #include <errno.h>
1.13 djm 22: #include <stdlib.h>
1.3 millert 23: #include <stdint.h>
1.1 djm 24: #include <stdio.h>
1.13 djm 25: #include <limits.h>
1.1 djm 26: #include <string.h>
1.13 djm 27: #include <resolv.h>
28: #include <ctype.h>
1.1 djm 29:
30: #include "ssherr.h"
31: #define SSHBUF_INTERNAL
32: #include "sshbuf.h"
33:
34: void
1.2 djm 35: sshbuf_dump_data(const void *s, size_t len, FILE *f)
1.1 djm 36: {
1.2 djm 37: size_t i, j;
38: const u_char *p = (const u_char *)s;
1.1 djm 39:
40: for (i = 0; i < len; i += 16) {
1.4 markus 41: fprintf(f, "%.4zu: ", i);
1.1 djm 42: for (j = i; j < i + 16; j++) {
43: if (j < len)
44: fprintf(f, "%02x ", p[j]);
45: else
46: fprintf(f, " ");
47: }
48: fprintf(f, " ");
49: for (j = i; j < i + 16; j++) {
50: if (j < len) {
51: if (isascii(p[j]) && isprint(p[j]))
52: fprintf(f, "%c", p[j]);
53: else
54: fprintf(f, ".");
55: }
56: }
57: fprintf(f, "\n");
58: }
1.2 djm 59: }
60:
61: void
1.15 djm 62: sshbuf_dump(const struct sshbuf *buf, FILE *f)
1.2 djm 63: {
1.17 ! djm 64: fprintf(f, "buffer len = %zu\n", sshbuf_len(buf));
1.2 djm 65: sshbuf_dump_data(sshbuf_ptr(buf), sshbuf_len(buf), f);
1.1 djm 66: }
67:
68: char *
69: sshbuf_dtob16(struct sshbuf *buf)
70: {
71: size_t i, j, len = sshbuf_len(buf);
72: const u_char *p = sshbuf_ptr(buf);
73: char *ret;
74: const char hex[] = "0123456789abcdef";
75:
76: if (len == 0)
77: return strdup("");
78: if (SIZE_MAX / 2 <= len || (ret = malloc(len * 2 + 1)) == NULL)
79: return NULL;
80: for (i = j = 0; i < len; i++) {
81: ret[j++] = hex[(p[i] >> 4) & 0xf];
82: ret[j++] = hex[p[i] & 0xf];
83: }
84: ret[j] = '\0';
85: return ret;
86: }
87:
1.9 djm 88: int
89: sshbuf_dtob64(const struct sshbuf *d, struct sshbuf *b64, int wrap)
90: {
91: size_t i, slen = 0;
92: char *s = NULL;
93: int r;
94:
95: if (d == NULL || b64 == NULL || sshbuf_len(d) >= SIZE_MAX / 2)
96: return SSH_ERR_INVALID_ARGUMENT;
97: if (sshbuf_len(d) == 0)
98: return 0;
99: slen = ((sshbuf_len(d) + 2) / 3) * 4 + 1;
100: if ((s = malloc(slen)) == NULL)
101: return SSH_ERR_ALLOC_FAIL;
102: if (b64_ntop(sshbuf_ptr(d), sshbuf_len(d), s, slen) == -1) {
103: r = SSH_ERR_INTERNAL_ERROR;
104: goto fail;
105: }
106: if (wrap) {
107: for (i = 0; s[i] != '\0'; i++) {
108: if ((r = sshbuf_put_u8(b64, s[i])) != 0)
109: goto fail;
110: if (i % 70 == 69 && (r = sshbuf_put_u8(b64, '\n')) != 0)
111: goto fail;
112: }
1.10 djm 113: if ((i - 1) % 70 != 69 && (r = sshbuf_put_u8(b64, '\n')) != 0)
1.9 djm 114: goto fail;
115: } else {
116: if ((r = sshbuf_put(b64, s, strlen(s))) != 0)
117: goto fail;
118: }
119: /* Success */
120: r = 0;
121: fail:
122: freezero(s, slen);
123: return r;
124: }
125:
1.1 djm 126: char *
1.9 djm 127: sshbuf_dtob64_string(const struct sshbuf *buf, int wrap)
1.1 djm 128: {
1.9 djm 129: struct sshbuf *tmp;
1.1 djm 130: char *ret;
131:
1.9 djm 132: if ((tmp = sshbuf_new()) == NULL)
1.1 djm 133: return NULL;
1.9 djm 134: if (sshbuf_dtob64(buf, tmp, wrap) != 0) {
135: sshbuf_free(tmp);
1.1 djm 136: return NULL;
137: }
1.9 djm 138: ret = sshbuf_dup_string(tmp);
139: sshbuf_free(tmp);
1.1 djm 140: return ret;
141: }
142:
143: int
144: sshbuf_b64tod(struct sshbuf *buf, const char *b64)
145: {
146: size_t plen = strlen(b64);
147: int nlen, r;
148: u_char *p;
149:
150: if (plen == 0)
151: return 0;
152: if ((p = malloc(plen)) == NULL)
153: return SSH_ERR_ALLOC_FAIL;
154: if ((nlen = b64_pton(b64, p, plen)) < 0) {
1.14 jsg 155: freezero(p, plen);
1.1 djm 156: return SSH_ERR_INVALID_FORMAT;
157: }
158: if ((r = sshbuf_put(buf, p, nlen)) < 0) {
1.14 jsg 159: freezero(p, plen);
1.1 djm 160: return r;
161: }
1.14 jsg 162: freezero(p, plen);
1.1 djm 163: return 0;
1.16 djm 164: }
165:
166: int
167: sshbuf_dtourlb64(const struct sshbuf *d, struct sshbuf *b64, int wrap)
168: {
169: int r = SSH_ERR_INTERNAL_ERROR;
170: u_char *p;
171: struct sshbuf *b = NULL;
172: size_t i, l;
173:
174: if ((b = sshbuf_new()) == NULL)
175: return SSH_ERR_ALLOC_FAIL;
176: /* Encode using regular base64; we'll transform it once done */
177: if ((r = sshbuf_dtob64(d, b, wrap)) != 0)
178: goto out;
179: /* remove padding from end of encoded string*/
180: for (;;) {
181: l = sshbuf_len(b);
182: if (l <= 1 || sshbuf_ptr(b) == NULL) {
183: r = SSH_ERR_INTERNAL_ERROR;
184: goto out;
185: }
186: if (sshbuf_ptr(b)[l - 1] != '=')
187: break;
188: if ((r = sshbuf_consume_end(b, 1)) != 0)
189: goto out;
190: }
191: /* Replace characters with rfc4648 equivalents */
192: l = sshbuf_len(b);
193: if ((p = sshbuf_mutable_ptr(b)) == NULL) {
194: r = SSH_ERR_INTERNAL_ERROR;
195: goto out;
196: }
197: for (i = 0; i < l; i++) {
198: if (p[i] == '+')
199: p[i] = '-';
200: else if (p[i] == '/')
201: p[i] = '_';
202: }
203: r = sshbuf_putb(b64, b);
204: out:
205: sshbuf_free(b);
206: return r;
1.6 djm 207: }
208:
209: char *
210: sshbuf_dup_string(struct sshbuf *buf)
211: {
212: const u_char *p = NULL, *s = sshbuf_ptr(buf);
213: size_t l = sshbuf_len(buf);
214: char *r;
215:
216: if (s == NULL || l > SIZE_MAX)
217: return NULL;
218: /* accept a nul only as the last character in the buffer */
219: if (l > 0 && (p = memchr(s, '\0', l)) != NULL) {
220: if (p != s + l - 1)
221: return NULL;
222: l--; /* the nul is put back below */
223: }
224: if ((r = malloc(l + 1)) == NULL)
225: return NULL;
226: if (l > 0)
227: memcpy(r, s, l);
228: r[l] = '\0';
229: return r;
1.1 djm 230: }
231:
1.8 djm 232: int
233: sshbuf_cmp(const struct sshbuf *b, size_t offset,
1.11 djm 234: const void *s, size_t len)
1.8 djm 235: {
236: if (sshbuf_ptr(b) == NULL)
237: return SSH_ERR_INTERNAL_ERROR;
238: if (offset > SSHBUF_SIZE_MAX || len > SSHBUF_SIZE_MAX || len == 0)
239: return SSH_ERR_INVALID_ARGUMENT;
240: if (offset + len > sshbuf_len(b))
241: return SSH_ERR_MESSAGE_INCOMPLETE;
242: if (timingsafe_bcmp(sshbuf_ptr(b) + offset, s, len) != 0)
243: return SSH_ERR_INVALID_FORMAT;
244: return 0;
245: }
246:
247: int
248: sshbuf_find(const struct sshbuf *b, size_t start_offset,
1.11 djm 249: const void *s, size_t len, size_t *offsetp)
1.8 djm 250: {
251: void *p;
252:
253: if (offsetp != NULL)
254: *offsetp = 0;
255: if (sshbuf_ptr(b) == NULL)
256: return SSH_ERR_INTERNAL_ERROR;
257: if (start_offset > SSHBUF_SIZE_MAX || len > SSHBUF_SIZE_MAX || len == 0)
258: return SSH_ERR_INVALID_ARGUMENT;
259: if (start_offset > sshbuf_len(b) || start_offset + len > sshbuf_len(b))
260: return SSH_ERR_MESSAGE_INCOMPLETE;
261: if ((p = memmem(sshbuf_ptr(b) + start_offset,
262: sshbuf_len(b) - start_offset, s, len)) == NULL)
263: return SSH_ERR_INVALID_FORMAT;
264: if (offsetp != NULL)
265: *offsetp = (const u_char *)p - sshbuf_ptr(b);
266: return 0;
267: }