1 files changed, 144 insertions, 0 deletions
diff --git a/usr.bin/ssh/digest.c b/usr.bin/ssh/digest.c
new file mode 100644
index 00000000000..667d3d948c0
--- /dev/null
+++ b/usr.bin/ssh/digest.c
@@ -0,0 +1,144 @@
+/* $OpenBSD: digest.c,v 1.1 2014/01/09 23:20:00 djm Exp $ */
+/*
+ * Copyright (c) 2013 Damien Miller <djm@mindrot.org>
+ *
+ * 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 <sys/types.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <openssl/bn.h> /* for buffer.h */
+#include <openssl/ec.h> /* for buffer.h */
+#include <openssl/evp.h>
+
+#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 },
+	{ SSH_DIGEST_SHA256,	"SHA256", 	32,	EVP_sha256 },
+	{ SSH_DIGEST_SHA384,	"SHA384",	48,	EVP_sha384 },
+	{ SSH_DIGEST_SHA512,	"SHA512", 	64,	EVP_sha512 },
+	{ -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);
+}