Annotation of src/usr.bin/ssh/digest-openssl.c, Revision 1.8
1.8 ! djm 1: /* $OpenBSD: digest-openssl.c,v 1.7 2017/05/08 22:57:38 djm Exp $ */
1.1 markus 2: /*
3: * Copyright (c) 2013 Damien Miller <djm@mindrot.org>
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 <limits.h>
20: #include <stdlib.h>
21: #include <string.h>
22:
23: #include <openssl/evp.h>
24:
1.3 djm 25: #include "sshbuf.h"
1.1 markus 26: #include "digest.h"
1.3 djm 27: #include "ssherr.h"
1.1 markus 28:
29: struct ssh_digest_ctx {
30: int alg;
1.8 ! djm 31: EVP_MD_CTX *mdctx;
1.1 markus 32: };
33:
34: struct ssh_digest {
35: int id;
36: const char *name;
37: size_t digest_len;
38: const EVP_MD *(*mdfunc)(void);
39: };
40:
41: /* NB. Indexed directly by algorithm number */
42: const struct ssh_digest digests[] = {
43: { SSH_DIGEST_MD5, "MD5", 16, EVP_md5 },
44: { SSH_DIGEST_SHA1, "SHA1", 20, EVP_sha1 },
45: { SSH_DIGEST_SHA256, "SHA256", 32, EVP_sha256 },
46: { SSH_DIGEST_SHA384, "SHA384", 48, EVP_sha384 },
47: { SSH_DIGEST_SHA512, "SHA512", 64, EVP_sha512 },
48: { -1, NULL, 0, NULL },
49: };
50:
51: static const struct ssh_digest *
52: ssh_digest_by_alg(int alg)
53: {
54: if (alg < 0 || alg >= SSH_DIGEST_MAX)
55: return NULL;
56: if (digests[alg].id != alg) /* sanity */
57: return NULL;
58: return &(digests[alg]);
1.5 djm 59: }
60:
61: int
62: ssh_digest_alg_by_name(const char *name)
63: {
64: int alg;
65:
66: for (alg = 0; digests[alg].id != -1; alg++) {
67: if (strcasecmp(name, digests[alg].name) == 0)
68: return digests[alg].id;
69: }
70: return -1;
71: }
72:
73: const char *
74: ssh_digest_alg_name(int alg)
75: {
76: const struct ssh_digest *digest = ssh_digest_by_alg(alg);
77:
78: return digest == NULL ? NULL : digest->name;
1.1 markus 79: }
80:
81: size_t
82: ssh_digest_bytes(int alg)
83: {
84: const struct ssh_digest *digest = ssh_digest_by_alg(alg);
85:
86: return digest == NULL ? 0 : digest->digest_len;
87: }
88:
89: size_t
90: ssh_digest_blocksize(struct ssh_digest_ctx *ctx)
91: {
1.8 ! djm 92: return EVP_MD_CTX_block_size(ctx->mdctx);
1.1 markus 93: }
94:
95: struct ssh_digest_ctx *
96: ssh_digest_start(int alg)
97: {
98: const struct ssh_digest *digest = ssh_digest_by_alg(alg);
99: struct ssh_digest_ctx *ret;
100:
101: if (digest == NULL || ((ret = calloc(1, sizeof(*ret))) == NULL))
102: return NULL;
103: ret->alg = alg;
1.8 ! djm 104: if ((ret->mdctx = EVP_MD_CTX_new()) == NULL) {
1.1 markus 105: free(ret);
106: return NULL;
107: }
1.8 ! djm 108: if (EVP_DigestInit_ex(ret->mdctx, digest->mdfunc(), NULL) != 1) {
! 109: ssh_digest_free(ret);
! 110: return NULL;
! 111: }
1.1 markus 112: return ret;
113: }
114:
115: int
116: ssh_digest_copy_state(struct ssh_digest_ctx *from, struct ssh_digest_ctx *to)
117: {
1.3 djm 118: if (from->alg != to->alg)
119: return SSH_ERR_INVALID_ARGUMENT;
1.1 markus 120: /* we have bcopy-style order while openssl has memcpy-style */
1.8 ! djm 121: if (!EVP_MD_CTX_copy_ex(to->mdctx, from->mdctx))
1.3 djm 122: return SSH_ERR_LIBCRYPTO_ERROR;
1.1 markus 123: return 0;
124: }
125:
126: int
127: ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen)
128: {
1.8 ! djm 129: if (EVP_DigestUpdate(ctx->mdctx, m, mlen) != 1)
1.3 djm 130: return SSH_ERR_LIBCRYPTO_ERROR;
1.1 markus 131: return 0;
132: }
133:
134: int
1.3 djm 135: ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const struct sshbuf *b)
1.1 markus 136: {
1.3 djm 137: return ssh_digest_update(ctx, sshbuf_ptr(b), sshbuf_len(b));
1.1 markus 138: }
139:
140: int
141: ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen)
142: {
143: const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg);
144: u_int l = dlen;
145:
1.6 dtucker 146: if (digest == NULL || dlen > UINT_MAX)
1.3 djm 147: return SSH_ERR_INVALID_ARGUMENT;
1.1 markus 148: if (dlen < digest->digest_len) /* No truncation allowed */
1.3 djm 149: return SSH_ERR_INVALID_ARGUMENT;
1.8 ! djm 150: if (EVP_DigestFinal_ex(ctx->mdctx, d, &l) != 1)
1.3 djm 151: return SSH_ERR_LIBCRYPTO_ERROR;
1.1 markus 152: if (l != digest->digest_len) /* sanity */
1.3 djm 153: return SSH_ERR_INTERNAL_ERROR;
1.1 markus 154: return 0;
155: }
156:
157: void
158: ssh_digest_free(struct ssh_digest_ctx *ctx)
159: {
1.8 ! djm 160: if (ctx == NULL)
! 161: return;
! 162: EVP_MD_CTX_free(ctx->mdctx);
! 163: freezero(ctx, sizeof(*ctx));
1.1 markus 164: }
165:
166: int
167: ssh_digest_memory(int alg, const void *m, size_t mlen, u_char *d, size_t dlen)
168: {
1.4 djm 169: const struct ssh_digest *digest = ssh_digest_by_alg(alg);
170: u_int mdlen;
1.1 markus 171:
1.4 djm 172: if (digest == NULL)
173: return SSH_ERR_INVALID_ARGUMENT;
174: if (dlen > UINT_MAX)
1.3 djm 175: return SSH_ERR_INVALID_ARGUMENT;
1.4 djm 176: if (dlen < digest->digest_len)
177: return SSH_ERR_INVALID_ARGUMENT;
178: mdlen = dlen;
179: if (!EVP_Digest(m, mlen, d, &mdlen, digest->mdfunc(), NULL))
180: return SSH_ERR_LIBCRYPTO_ERROR;
1.1 markus 181: return 0;
182: }
183:
184: int
1.3 djm 185: ssh_digest_buffer(int alg, const struct sshbuf *b, u_char *d, size_t dlen)
1.1 markus 186: {
1.3 djm 187: return ssh_digest_memory(alg, sshbuf_ptr(b), sshbuf_len(b), d, dlen);
1.1 markus 188: }