xref: /freebsd/crypto/openssh/digest-libc.c (revision 41059135ce931c0f1014a999ffabc6bc470ce856)
1 /* $OpenBSD: digest-libc.c,v 1.5 2015/05/05 02:48:17 jsg Exp $ */
2 /*
3  * Copyright (c) 2013 Damien Miller <djm@mindrot.org>
4  * Copyright (c) 2014 Markus Friedl.  All rights reserved.
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 "includes.h"
20 
21 #ifndef WITH_OPENSSL
22 
23 #include <sys/types.h>
24 #include <limits.h>
25 #include <stdlib.h>
26 #include <string.h>
27 
28 #if 0
29 #include <md5.h>
30 #include <rmd160.h>
31 #include <sha1.h>
32 #include <sha2.h>
33 #endif
34 
35 #include "ssherr.h"
36 #include "sshbuf.h"
37 #include "digest.h"
38 
39 typedef void md_init_fn(void *mdctx);
40 typedef void md_update_fn(void *mdctx, const u_int8_t *m, size_t mlen);
41 typedef void md_final_fn(u_int8_t[], void *mdctx);
42 
43 struct ssh_digest_ctx {
44 	int alg;
45 	void *mdctx;
46 };
47 
48 struct ssh_digest {
49 	int id;
50 	const char *name;
51 	size_t block_len;
52 	size_t digest_len;
53 	size_t ctx_len;
54 	md_init_fn *md_init;
55 	md_update_fn *md_update;
56 	md_final_fn *md_final;
57 };
58 
59 /* NB. Indexed directly by algorithm number */
60 const struct ssh_digest digests[SSH_DIGEST_MAX] = {
61 	{
62 		SSH_DIGEST_MD5,
63 		"MD5",
64 		MD5_BLOCK_LENGTH,
65 		MD5_DIGEST_LENGTH,
66 		sizeof(MD5_CTX),
67 		(md_init_fn *) MD5Init,
68 		(md_update_fn *) MD5Update,
69 		(md_final_fn *) MD5Final
70 	},
71 	{
72 		SSH_DIGEST_RIPEMD160,
73 		"RIPEMD160",
74 		RMD160_BLOCK_LENGTH,
75 		RMD160_DIGEST_LENGTH,
76 		sizeof(RMD160_CTX),
77 		(md_init_fn *) RMD160Init,
78 		(md_update_fn *) RMD160Update,
79 		(md_final_fn *) RMD160Final
80 	},
81 	{
82 		SSH_DIGEST_SHA1,
83 		"SHA1",
84 		SHA1_BLOCK_LENGTH,
85 		SHA1_DIGEST_LENGTH,
86 		sizeof(SHA1_CTX),
87 		(md_init_fn *) SHA1Init,
88 		(md_update_fn *) SHA1Update,
89 		(md_final_fn *) SHA1Final
90 	},
91 	{
92 		SSH_DIGEST_SHA256,
93 		"SHA256",
94 		SHA256_BLOCK_LENGTH,
95 		SHA256_DIGEST_LENGTH,
96 		sizeof(SHA256_CTX),
97 		(md_init_fn *) SHA256_Init,
98 		(md_update_fn *) SHA256_Update,
99 		(md_final_fn *) SHA256_Final
100 	},
101 	{
102 		SSH_DIGEST_SHA384,
103 		"SHA384",
104 		SHA384_BLOCK_LENGTH,
105 		SHA384_DIGEST_LENGTH,
106 		sizeof(SHA384_CTX),
107 		(md_init_fn *) SHA384_Init,
108 		(md_update_fn *) SHA384_Update,
109 		(md_final_fn *) SHA384_Final
110 	},
111 	{
112 		SSH_DIGEST_SHA512,
113 		"SHA512",
114 		SHA512_BLOCK_LENGTH,
115 		SHA512_DIGEST_LENGTH,
116 		sizeof(SHA512_CTX),
117 		(md_init_fn *) SHA512_Init,
118 		(md_update_fn *) SHA512_Update,
119 		(md_final_fn *) SHA512_Final
120 	}
121 };
122 
123 static const struct ssh_digest *
124 ssh_digest_by_alg(int alg)
125 {
126 	if (alg < 0 || alg >= SSH_DIGEST_MAX)
127 		return NULL;
128 	if (digests[alg].id != alg) /* sanity */
129 		return NULL;
130 	return &(digests[alg]);
131 }
132 
133 int
134 ssh_digest_alg_by_name(const char *name)
135 {
136 	int alg;
137 
138 	for (alg = 0; alg < SSH_DIGEST_MAX; alg++) {
139 		if (strcasecmp(name, digests[alg].name) == 0)
140 			return digests[alg].id;
141 	}
142 	return -1;
143 }
144 
145 const char *
146 ssh_digest_alg_name(int alg)
147 {
148 	const struct ssh_digest *digest = ssh_digest_by_alg(alg);
149 
150 	return digest == NULL ? NULL : digest->name;
151 }
152 
153 size_t
154 ssh_digest_bytes(int alg)
155 {
156 	const struct ssh_digest *digest = ssh_digest_by_alg(alg);
157 
158 	return digest == NULL ? 0 : digest->digest_len;
159 }
160 
161 size_t
162 ssh_digest_blocksize(struct ssh_digest_ctx *ctx)
163 {
164 	const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg);
165 
166 	return digest == NULL ? 0 : digest->block_len;
167 }
168 
169 struct ssh_digest_ctx *
170 ssh_digest_start(int alg)
171 {
172 	const struct ssh_digest *digest = ssh_digest_by_alg(alg);
173 	struct ssh_digest_ctx *ret;
174 
175 	if (digest == NULL || (ret = calloc(1, sizeof(*ret))) == NULL)
176 		return NULL;
177 	if ((ret->mdctx = calloc(1, digest->ctx_len)) == NULL) {
178 		free(ret);
179 		return NULL;
180 	}
181 	ret->alg = alg;
182 	digest->md_init(ret->mdctx);
183 	return ret;
184 }
185 
186 int
187 ssh_digest_copy_state(struct ssh_digest_ctx *from, struct ssh_digest_ctx *to)
188 {
189 	const struct ssh_digest *digest = ssh_digest_by_alg(from->alg);
190 
191 	if (digest == NULL || from->alg != to->alg)
192 		return SSH_ERR_INVALID_ARGUMENT;
193 	memcpy(to->mdctx, from->mdctx, digest->ctx_len);
194 	return 0;
195 }
196 
197 int
198 ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen)
199 {
200 	const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg);
201 
202 	if (digest == NULL)
203 		return SSH_ERR_INVALID_ARGUMENT;
204 	digest->md_update(ctx->mdctx, m, mlen);
205 	return 0;
206 }
207 
208 int
209 ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const struct sshbuf *b)
210 {
211 	return ssh_digest_update(ctx, sshbuf_ptr(b), sshbuf_len(b));
212 }
213 
214 int
215 ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen)
216 {
217 	const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg);
218 
219 	if (digest == NULL)
220 		return SSH_ERR_INVALID_ARGUMENT;
221 	if (dlen > UINT_MAX)
222 		return SSH_ERR_INVALID_ARGUMENT;
223 	if (dlen < digest->digest_len) /* No truncation allowed */
224 		return SSH_ERR_INVALID_ARGUMENT;
225 	digest->md_final(d, ctx->mdctx);
226 	return 0;
227 }
228 
229 void
230 ssh_digest_free(struct ssh_digest_ctx *ctx)
231 {
232 	const struct ssh_digest *digest;
233 
234 	if (ctx != NULL) {
235 		digest = ssh_digest_by_alg(ctx->alg);
236 		if (digest) {
237 			explicit_bzero(ctx->mdctx, digest->ctx_len);
238 			free(ctx->mdctx);
239 			explicit_bzero(ctx, sizeof(*ctx));
240 			free(ctx);
241 		}
242 	}
243 }
244 
245 int
246 ssh_digest_memory(int alg, const void *m, size_t mlen, u_char *d, size_t dlen)
247 {
248 	struct ssh_digest_ctx *ctx = ssh_digest_start(alg);
249 
250 	if (ctx == NULL)
251 		return SSH_ERR_INVALID_ARGUMENT;
252 	if (ssh_digest_update(ctx, m, mlen) != 0 ||
253 	    ssh_digest_final(ctx, d, dlen) != 0)
254 		return SSH_ERR_INVALID_ARGUMENT;
255 	ssh_digest_free(ctx);
256 	return 0;
257 }
258 
259 int
260 ssh_digest_buffer(int alg, const struct sshbuf *b, u_char *d, size_t dlen)
261 {
262 	return ssh_digest_memory(alg, sshbuf_ptr(b), sshbuf_len(b), d, dlen);
263 }
264 #endif /* !WITH_OPENSSL */
265