1 /* $OpenBSD: digest-openssl.c,v 1.5 2014/12/21 22:27:56 djm Exp $ */ 2 /* 3 * Copyright (c) 2013 Damien Miller <djm (at) 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 "includes.h" 19 20 #ifdef WITH_OPENSSL 21 22 #include <sys/types.h> 23 #include <limits.h> 24 #include <stdlib.h> 25 #include <string.h> 26 27 #include <openssl/evp.h> 28 29 #include "openbsd-compat/openssl-compat.h" 30 31 #include "sshbuf.h" 32 #include "digest.h" 33 #include "ssherr.h" 34 35 #ifndef HAVE_EVP_RIPEMD160 36 # define EVP_ripemd160 NULL 37 #endif /* HAVE_EVP_RIPEMD160 */ 38 #ifndef HAVE_EVP_SHA256 39 # define EVP_sha256 NULL 40 # define EVP_sha384 NULL 41 # define EVP_sha512 NULL 42 #endif /* HAVE_EVP_SHA256 */ 43 44 struct ssh_digest_ctx { 45 int alg; 46 EVP_MD_CTX mdctx; 47 }; 48 49 struct ssh_digest { 50 int id; 51 const char *name; 52 size_t digest_len; 53 const EVP_MD *(*mdfunc)(void); 54 }; 55 56 /* NB. Indexed directly by algorithm number */ 57 const struct ssh_digest digests[] = { 58 { SSH_DIGEST_MD5, "MD5", 16, EVP_md5 }, 59 { SSH_DIGEST_RIPEMD160, "RIPEMD160", 20, EVP_ripemd160 }, 60 { SSH_DIGEST_SHA1, "SHA1", 20, EVP_sha1 }, 61 { SSH_DIGEST_SHA256, "SHA256", 32, EVP_sha256 }, 62 { SSH_DIGEST_SHA384, "SHA384", 48, EVP_sha384 }, 63 { SSH_DIGEST_SHA512, "SHA512", 64, EVP_sha512 }, 64 { -1, NULL, 0, NULL }, 65 }; 66 67 static const struct ssh_digest * 68 ssh_digest_by_alg(int alg) 69 { 70 if (alg < 0 || alg >= SSH_DIGEST_MAX) 71 return NULL; 72 if (digests[alg].id != alg) /* sanity */ 73 return NULL; 74 if (digests[alg].mdfunc == NULL) 75 return NULL; 76 return &(digests[alg]); 77 } 78 79 int 80 ssh_digest_alg_by_name(const char *name) 81 { 82 int alg; 83 84 for (alg = 0; digests[alg].id != -1; alg++) { 85 if (strcasecmp(name, digests[alg].name) == 0) 86 return digests[alg].id; 87 } 88 return -1; 89 } 90 91 const char * 92 ssh_digest_alg_name(int alg) 93 { 94 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 95 96 return digest == NULL ? NULL : digest->name; 97 } 98 99 size_t 100 ssh_digest_bytes(int alg) 101 { 102 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 103 104 return digest == NULL ? 0 : digest->digest_len; 105 } 106 107 size_t 108 ssh_digest_blocksize(struct ssh_digest_ctx *ctx) 109 { 110 return EVP_MD_CTX_block_size(&ctx->mdctx); 111 } 112 113 struct ssh_digest_ctx * 114 ssh_digest_start(int alg) 115 { 116 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 117 struct ssh_digest_ctx *ret; 118 119 if (digest == NULL || ((ret = calloc(1, sizeof(*ret))) == NULL)) 120 return NULL; 121 ret->alg = alg; 122 EVP_MD_CTX_init(&ret->mdctx); 123 if (EVP_DigestInit_ex(&ret->mdctx, digest->mdfunc(), NULL) != 1) { 124 free(ret); 125 return NULL; 126 } 127 return ret; 128 } 129 130 int 131 ssh_digest_copy_state(struct ssh_digest_ctx *from, struct ssh_digest_ctx *to) 132 { 133 if (from->alg != to->alg) 134 return SSH_ERR_INVALID_ARGUMENT; 135 /* we have bcopy-style order while openssl has memcpy-style */ 136 if (!EVP_MD_CTX_copy_ex(&to->mdctx, &from->mdctx)) 137 return SSH_ERR_LIBCRYPTO_ERROR; 138 return 0; 139 } 140 141 int 142 ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen) 143 { 144 if (EVP_DigestUpdate(&ctx->mdctx, m, mlen) != 1) 145 return SSH_ERR_LIBCRYPTO_ERROR; 146 return 0; 147 } 148 149 int 150 ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const struct sshbuf *b) 151 { 152 return ssh_digest_update(ctx, sshbuf_ptr(b), sshbuf_len(b)); 153 } 154 155 int 156 ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen) 157 { 158 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 159 u_int l = dlen; 160 161 if (dlen > UINT_MAX) 162 return SSH_ERR_INVALID_ARGUMENT; 163 if (dlen < digest->digest_len) /* No truncation allowed */ 164 return SSH_ERR_INVALID_ARGUMENT; 165 if (EVP_DigestFinal_ex(&ctx->mdctx, d, &l) != 1) 166 return SSH_ERR_LIBCRYPTO_ERROR; 167 if (l != digest->digest_len) /* sanity */ 168 return SSH_ERR_INTERNAL_ERROR; 169 return 0; 170 } 171 172 void 173 ssh_digest_free(struct ssh_digest_ctx *ctx) 174 { 175 if (ctx != NULL) { 176 EVP_MD_CTX_cleanup(&ctx->mdctx); 177 explicit_bzero(ctx, sizeof(*ctx)); 178 free(ctx); 179 } 180 } 181 182 int 183 ssh_digest_memory(int alg, const void *m, size_t mlen, u_char *d, size_t dlen) 184 { 185 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 186 u_int mdlen; 187 188 if (digest == NULL) 189 return SSH_ERR_INVALID_ARGUMENT; 190 if (dlen > UINT_MAX) 191 return SSH_ERR_INVALID_ARGUMENT; 192 if (dlen < digest->digest_len) 193 return SSH_ERR_INVALID_ARGUMENT; 194 mdlen = dlen; 195 if (!EVP_Digest(m, mlen, d, &mdlen, digest->mdfunc(), NULL)) 196 return SSH_ERR_LIBCRYPTO_ERROR; 197 return 0; 198 } 199 200 int 201 ssh_digest_buffer(int alg, const struct sshbuf *b, u_char *d, size_t dlen) 202 { 203 return ssh_digest_memory(alg, sshbuf_ptr(b), sshbuf_len(b), d, dlen); 204 } 205 #endif /* WITH_OPENSSL */ 206
