From b3051d01e505c9c2dc00faab472a0d06fa6b0e65 Mon Sep 17 00:00:00 2001 From: Damien Miller Date: Fri, 10 Jan 2014 10:58:53 +1100 Subject: - djm@cvs.openbsd.org 2014/01/09 23:20:00 [digest.c digest.h hostfile.c kex.c kex.h kexc25519.c kexc25519c.c] [kexc25519s.c kexdh.c kexecdh.c kexecdhc.c kexecdhs.c kexgex.c kexgexc.c] [kexgexs.c key.c key.h roaming_client.c roaming_common.c schnorr.c] [schnorr.h ssh-dss.c ssh-ecdsa.c ssh-rsa.c sshconnect2.c] Introduce digest API and use it to perform all hashing operations rather than calling OpenSSL EVP_Digest* directly. Will make it easier to build a reduced-feature OpenSSH without OpenSSL in future; feedback, ok markus@ --- digest.c | 148 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 148 insertions(+) create mode 100644 digest.c (limited to 'digest.c') diff --git a/digest.c b/digest.c new file mode 100644 index 000000000..59a8ffe0d --- /dev/null +++ b/digest.c @@ -0,0 +1,148 @@ +/* $OpenBSD: digest.c,v 1.1 2014/01/09 23:20:00 djm Exp $ */ +/* + * Copyright (c) 2013 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 +#include +#include +#include + +#include /* for buffer.h */ +#include /* for buffer.h */ +#include + +#include "buffer.h" +#include "digest.h" + +struct ssh_digest_ctx { + int alg; + EVP_MD_CTX mdctx; +}; + +struct ssh_digest { + int id; + const char *name; + size_t digest_len; + const EVP_MD *(*mdfunc)(void); +}; + +/* NB. Indexed directly by algorithm number */ +const struct ssh_digest digests[] = { + { SSH_DIGEST_MD5, "MD5", 16, EVP_md5 }, + { SSH_DIGEST_RIPEMD160, "RIPEMD160", 20, EVP_ripemd160 }, + { SSH_DIGEST_SHA1, "SHA1", 20, EVP_sha1 }, +#ifdef HAVE_EVP_SHA256 /* XXX replace with local if missing */ + { SSH_DIGEST_SHA256, "SHA256", 32, EVP_sha256 }, + { SSH_DIGEST_SHA384, "SHA384", 48, EVP_sha384 }, + { SSH_DIGEST_SHA512, "SHA512", 64, EVP_sha512 }, +#endif + { -1, NULL, 0, NULL }, +}; + +static const struct ssh_digest * +ssh_digest_by_alg(int alg) +{ + if (alg < 0 || alg >= SSH_DIGEST_MAX) + return NULL; + if (digests[alg].id != alg) /* sanity */ + return NULL; + return &(digests[alg]); +} + +size_t +ssh_digest_bytes(int alg) +{ + const struct ssh_digest *digest = ssh_digest_by_alg(alg); + + return digest == NULL ? 0 : digest->digest_len; +} + +struct ssh_digest_ctx * +ssh_digest_start(int alg) +{ + const struct ssh_digest *digest = ssh_digest_by_alg(alg); + struct ssh_digest_ctx *ret; + + if (digest == NULL || ((ret = calloc(1, sizeof(*ret))) == NULL)) + return NULL; + ret->alg = alg; + EVP_MD_CTX_init(&ret->mdctx); + if (EVP_DigestInit_ex(&ret->mdctx, digest->mdfunc(), NULL) != 1) { + free(ret); + return NULL; + } + return ret; +} + +int +ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen) +{ + if (EVP_DigestUpdate(&ctx->mdctx, m, mlen) != 1) + return -1; + return 0; +} + +int +ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const Buffer *b) +{ + return ssh_digest_update(ctx, buffer_ptr(b), buffer_len(b)); +} + +int +ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen) +{ + const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); + u_int l = dlen; + + if (dlen > UINT_MAX) + return -1; + if (dlen < digest->digest_len) /* No truncation allowed */ + return -1; + if (EVP_DigestFinal_ex(&ctx->mdctx, d, &l) != 1) + return -1; + if (l != digest->digest_len) /* sanity */ + return -1; + return 0; +} + +void +ssh_digest_free(struct ssh_digest_ctx *ctx) +{ + EVP_MD_CTX_cleanup(&ctx->mdctx); + memset(ctx, 0, sizeof(*ctx)); +} + +int +ssh_digest_memory(int alg, const void *m, size_t mlen, u_char *d, size_t dlen) +{ + struct ssh_digest_ctx *ctx = ssh_digest_start(alg); + + if (ctx == NULL) + return -1; + if (ssh_digest_update(ctx, m, mlen) != 0 || + ssh_digest_final(ctx, d, dlen) != 0) + return -1; + ssh_digest_free(ctx); + return 0; +} + +int +ssh_digest_buffer(int alg, const Buffer *b, u_char *d, size_t dlen) +{ + return ssh_digest_memory(alg, buffer_ptr(b), buffer_len(b), d, dlen); +} -- cgit v1.2.3