/* $OpenBSD: digest-libc.c,v 1.7 2020/02/26 13:40:09 jsg Exp $ */ /* * Copyright (c) 2013 Damien Miller * Copyright (c) 2014 Markus Friedl. All rights reserved. * * 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" __RCSID("$NetBSD: digest-libc.c,v 1.7.6.1 2023/12/25 12:31:04 martin Exp $"); #include #include #include #include #include #include #include #include #include "ssherr.h" #include "sshbuf.h" #include "digest.h" typedef void md_init_fn(void *mdctx); typedef void md_update_fn(void *mdctx, const u_int8_t *m, size_t mlen); typedef void md_final_fn(u_int8_t[], void *mdctx); struct ssh_digest_ctx { int alg; void *mdctx; }; struct ssh_digest { int id; const char *name; size_t block_len; size_t digest_len; size_t ctx_len; md_init_fn *md_init; md_update_fn *md_update; md_final_fn *md_final; }; /* NB. Indexed directly by algorithm number */ const struct ssh_digest digests[SSH_DIGEST_MAX] = { { SSH_DIGEST_MD5, "MD5", MD5_BLOCK_LENGTH, MD5_DIGEST_LENGTH, sizeof(MD5_CTX), (md_init_fn *) MD5Init, (md_update_fn *) MD5Update, (md_final_fn *) MD5Final }, { SSH_DIGEST_SHA1, "SHA1", SHA1_BLOCK_LENGTH, SHA1_DIGEST_LENGTH, sizeof(SHA1_CTX), (md_init_fn *) SHA1Init, (md_update_fn *) SHA1Update, (md_final_fn *) SHA1Final }, { SSH_DIGEST_SHA256, "SHA256", SHA256_BLOCK_LENGTH, SHA256_DIGEST_LENGTH, sizeof(SHA2_CTX), (md_init_fn *) SHA256Init, (md_update_fn *) SHA256Update, (md_final_fn *) SHA256Final }, { SSH_DIGEST_SHA384, "SHA384", SHA384_BLOCK_LENGTH, SHA384_DIGEST_LENGTH, sizeof(SHA2_CTX), (md_init_fn *) SHA384Init, (md_update_fn *) SHA384Update, (md_final_fn *) SHA384Final }, { SSH_DIGEST_SHA512, "SHA512", SHA512_BLOCK_LENGTH, SHA512_DIGEST_LENGTH, sizeof(SHA2_CTX), (md_init_fn *) SHA512Init, (md_update_fn *) SHA512Update, (md_final_fn *) SHA512Final } }; 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]); } int ssh_digest_alg_by_name(const char *name) { int alg; for (alg = 0; alg < SSH_DIGEST_MAX; alg++) { if (strcasecmp(name, digests[alg].name) == 0) return digests[alg].id; } return -1; } const char * ssh_digest_alg_name(int alg) { const struct ssh_digest *digest = ssh_digest_by_alg(alg); return digest == NULL ? NULL : digest->name; } size_t ssh_digest_bytes(int alg) { const struct ssh_digest *digest = ssh_digest_by_alg(alg); return digest == NULL ? 0 : digest->digest_len; } size_t ssh_digest_blocksize(struct ssh_digest_ctx *ctx) { const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); return digest == NULL ? 0 : digest->block_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; if ((ret->mdctx = calloc(1, digest->ctx_len)) == NULL) { free(ret); return NULL; } ret->alg = alg; digest->md_init(ret->mdctx); return ret; } int ssh_digest_copy_state(struct ssh_digest_ctx *from, struct ssh_digest_ctx *to) { const struct ssh_digest *digest = ssh_digest_by_alg(from->alg); if (digest == NULL || from->alg != to->alg) return SSH_ERR_INVALID_ARGUMENT; memcpy(to->mdctx, from->mdctx, digest->ctx_len); return 0; } int ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen) { const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); if (digest == NULL) return SSH_ERR_INVALID_ARGUMENT; digest->md_update(ctx->mdctx, m, mlen); return 0; } int ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const struct sshbuf *b) { return ssh_digest_update(ctx, sshbuf_ptr(b), sshbuf_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); if (digest == NULL) return SSH_ERR_INVALID_ARGUMENT; if (dlen > UINT_MAX) return SSH_ERR_INVALID_ARGUMENT; if (dlen < digest->digest_len) /* No truncation allowed */ return SSH_ERR_INVALID_ARGUMENT; digest->md_final(d, ctx->mdctx); return 0; } void ssh_digest_free(struct ssh_digest_ctx *ctx) { const struct ssh_digest *digest; if (ctx != NULL) { digest = ssh_digest_by_alg(ctx->alg); if (digest) { explicit_bzero(ctx->mdctx, digest->ctx_len); free(ctx->mdctx); freezero(ctx, 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 SSH_ERR_INVALID_ARGUMENT; if (ssh_digest_update(ctx, m, mlen) != 0 || ssh_digest_final(ctx, d, dlen) != 0) return SSH_ERR_INVALID_ARGUMENT; ssh_digest_free(ctx); return 0; } int ssh_digest_buffer(int alg, const struct sshbuf *b, u_char *d, size_t dlen) { return ssh_digest_memory(alg, sshbuf_ptr(b), sshbuf_len(b), d, dlen); }