[PATCH] Add MD2 message digest implementation
Dmitry Eremin-Solenikov
dbaryshkov at gmail.com
Tue Mar 11 18:53:05 CET 2014
* cipher/md2.c: New.
* cipher/md.c (digest_list): add _gcry_digest_spec_md2.
* tests/basic.c (check_digests): add MD2 test vectors.
* configure.ac (default_digests): disable md2 by default.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov at gmail.com>
---
I was playing with old certificates and thus I needed MD2 algorithm.
Contributing it to libgcrypt now. Disabled by default for security
considerations.
cipher/md.c | 3 ++
cipher/md2.c | 158 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
configure.ac | 10 +++-
src/cipher.h | 1 +
tests/basic.c | 6 +++
5 files changed, 177 insertions(+), 1 deletion(-)
create mode 100644 cipher/md2.c
diff --git a/cipher/md.c b/cipher/md.c
index a332e03..461ad64 100644
--- a/cipher/md.c
+++ b/cipher/md.c
@@ -75,6 +75,9 @@ static gcry_md_spec_t *digest_list[] =
#if USE_MD4
&_gcry_digest_spec_md4,
#endif
+#if USE_MD2
+ &_gcry_digest_spec_md2,
+#endif
NULL
};
diff --git a/cipher/md2.c b/cipher/md2.c
new file mode 100644
index 0000000..f9171c8
--- /dev/null
+++ b/cipher/md2.c
@@ -0,0 +1,158 @@
+/* md2.c - MD2 Message-Digest Algorithm
+ * Copyright (C) 2014 Dmitry Eremin-Solenikov
+ *
+ * This file is part of Libgcrypt.
+ *
+ * Libgcrypt is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * Libgcrypt is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#include <config.h>
+
+#include "g10lib.h"
+#include "cipher.h"
+
+#include "bithelp.h"
+#include "bufhelp.h"
+#include "hash-common.h"
+
+typedef struct {
+ gcry_md_block_ctx_t bctx;
+ unsigned char C[16];
+ unsigned char L;
+ unsigned char X[48];
+} MD2_CONTEXT;
+
+static const unsigned char S[] = {
+ 0x29, 0x2E, 0x43, 0xC9, 0xA2, 0xD8, 0x7C, 0x01, 0x3D, 0x36, 0x54, 0xA1, 0xEC, 0xF0, 0x06, 0x13,
+ 0x62, 0xA7, 0x05, 0xF3, 0xC0, 0xC7, 0x73, 0x8C, 0x98, 0x93, 0x2B, 0xD9, 0xBC, 0x4C, 0x82, 0xCA,
+ 0x1E, 0x9B, 0x57, 0x3C, 0xFD, 0xD4, 0xE0, 0x16, 0x67, 0x42, 0x6F, 0x18, 0x8A, 0x17, 0xE5, 0x12,
+ 0xBE, 0x4E, 0xC4, 0xD6, 0xDA, 0x9E, 0xDE, 0x49, 0xA0, 0xFB, 0xF5, 0x8E, 0xBB, 0x2F, 0xEE, 0x7A,
+ 0xA9, 0x68, 0x79, 0x91, 0x15, 0xB2, 0x07, 0x3F, 0x94, 0xC2, 0x10, 0x89, 0x0B, 0x22, 0x5F, 0x21,
+ 0x80, 0x7F, 0x5D, 0x9A, 0x5A, 0x90, 0x32, 0x27, 0x35, 0x3E, 0xCC, 0xE7, 0xBF, 0xF7, 0x97, 0x03,
+ 0xFF, 0x19, 0x30, 0xB3, 0x48, 0xA5, 0xB5, 0xD1, 0xD7, 0x5E, 0x92, 0x2A, 0xAC, 0x56, 0xAA, 0xC6,
+ 0x4F, 0xB8, 0x38, 0xD2, 0x96, 0xA4, 0x7D, 0xB6, 0x76, 0xFC, 0x6B, 0xE2, 0x9C, 0x74, 0x04, 0xF1,
+ 0x45, 0x9D, 0x70, 0x59, 0x64, 0x71, 0x87, 0x20, 0x86, 0x5B, 0xCF, 0x65, 0xE6, 0x2D, 0xA8, 0x02,
+ 0x1B, 0x60, 0x25, 0xAD, 0xAE, 0xB0, 0xB9, 0xF6, 0x1C, 0x46, 0x61, 0x69, 0x34, 0x40, 0x7E, 0x0F,
+ 0x55, 0x47, 0xA3, 0x23, 0xDD, 0x51, 0xAF, 0x3A, 0xC3, 0x5C, 0xF9, 0xCE, 0xBA, 0xC5, 0xEA, 0x26,
+ 0x2C, 0x53, 0x0D, 0x6E, 0x85, 0x28, 0x84, 0x09, 0xD3, 0xDF, 0xCD, 0xF4, 0x41, 0x81, 0x4D, 0x52,
+ 0x6A, 0xDC, 0x37, 0xC8, 0x6C, 0xC1, 0xAB, 0xFA, 0x24, 0xE1, 0x7B, 0x08, 0x0C, 0xBD, 0xB1, 0x4A,
+ 0x78, 0x88, 0x95, 0x8B, 0xE3, 0x63, 0xE8, 0x6D, 0xE9, 0xCB, 0xD5, 0xFE, 0x3B, 0x00, 0x1D, 0x39,
+ 0xF2, 0xEF, 0xB7, 0x0E, 0x66, 0x58, 0xD0, 0xE4, 0xA6, 0x77, 0x72, 0xF8, 0xEB, 0x75, 0x4B, 0x0A,
+ 0x31, 0x44, 0x50, 0xB4, 0x8F, 0xED, 0x1F, 0x1A, 0xDB, 0x99, 0x8D, 0x33, 0x9F, 0x11, 0x83, 0x14
+};
+
+static void permute(unsigned char *X, const unsigned char *buf)
+{
+ int i, j;
+ unsigned char t;
+ memcpy(X+16, buf, 16);
+ for (i = 0; i < 16; i++)
+ X[32+i] = X[16+i] ^ X[i];
+ t = 0;
+ for (i = 0; i < 18; i++)
+ {
+ for (j = 0; j < 48; j++)
+ {
+ t = X[j] ^ S[t];
+ X[j] = t;
+ }
+ t += i;
+ }
+}
+
+
+static unsigned int
+transform_blk ( void *c, const unsigned char *data )
+{
+ MD2_CONTEXT *ctx = c;
+ int j;
+
+ for (j = 0; j < 16; j++)
+ {
+ ctx->C[j] ^= S[data[j] ^ ctx->L];
+ ctx->L = ctx->C[j];
+ }
+
+ permute(ctx->X, data);
+
+ return /* burn stack */ 4 + 5 * sizeof(void*);
+}
+
+static unsigned int
+transform ( void *c, const unsigned char *data, size_t nblks )
+{
+ unsigned int burn;
+
+ do
+ {
+ burn = transform_blk (c, data);
+ data += 64;
+ }
+ while (--nblks);
+
+ return burn;
+}
+
+static void
+md2_init( void *context, unsigned int flags)
+{
+ MD2_CONTEXT *ctx = context;
+
+ (void)flags;
+
+ memset (ctx, 0, sizeof(*ctx));
+ ctx->bctx.blocksize = 16;
+ ctx->bctx.bwrite = transform;
+}
+
+static void
+md2_final( void *context)
+{
+ MD2_CONTEXT *hd = context;
+ unsigned int burn;
+
+ _gcry_md_block_write(hd, NULL, 0); /* flush */;
+
+ /* pad */
+ memset (hd->bctx.buf + hd->bctx.count, 16 - hd->bctx.count, 16 - hd->bctx.count);
+ burn = transform_blk (hd, hd->bctx.buf);
+ permute (hd->X, hd->C);
+}
+
+static byte *
+md2_read( void *context )
+{
+ MD2_CONTEXT *hd = (MD2_CONTEXT *) context;
+ return hd->X;
+}
+
+static byte asn[18] = /* Object ID is 1.2.840.113549.2.2 */
+ { 0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a, 0x86,0x48,
+ 0x86, 0xf7, 0x0d, 0x02, 0x02, 0x05, 0x00, 0x04, 0x10 };
+
+static gcry_md_oid_spec_t oid_spec_md2[] =
+ {
+ /* iso.member-body.us.rsadsi.digestAlgorithm.md2 */
+ { "1.2.840.113549.2.2" },
+ { NULL },
+ };
+
+gcry_md_spec_t _gcry_digest_spec_md2 =
+ {
+ GCRY_MD_MD2, {0, 0},
+ "MD2", asn, DIM (asn), oid_spec_md2, 16,
+ md2_init, _gcry_md_block_write, md2_final, md2_read,
+ sizeof (MD2_CONTEXT)
+ };
diff --git a/configure.ac b/configure.ac
index a447859..a0f75a5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -194,7 +194,7 @@ available_pubkey_ciphers="dsa elgamal rsa ecc"
enabled_pubkey_ciphers=""
# Definitions for message digests.
-available_digests="crc gostr3411-94 md4 md5 rmd160 sha1 sha256"
+available_digests="crc gostr3411-94 md2 md4 md5 rmd160 sha1 sha256"
available_digests_64="sha512 tiger whirlpool stribog"
enabled_digests=""
@@ -377,6 +377,8 @@ default_ciphers="$available_ciphers"
default_pubkey_ciphers="$available_pubkey_ciphers"
default_digests="$available_digests"
default_kdfs="$available_kdfs"
+# Blacklist MD2 by default
+default_digests=`echo $default_digests | sed -e 's/md2//g'`
# Substitutions to set generated files in a Emacs buffer to read-only.
AC_SUBST(emacs_local_vars_begin, ['Local Variables:'])
@@ -1845,6 +1847,12 @@ if test "$found" = "1" ; then
AC_DEFINE(USE_GOST_R_3411_12, 1, [Defined if this module should be included])
fi
+LIST_MEMBER(md2, $enabled_digests)
+if test "$found" = "1" ; then
+ GCRYPT_DIGESTS="$GCRYPT_DIGESTS md2.lo"
+ AC_DEFINE(USE_MD2, 1, [Defined if this module should be included])
+fi
+
LIST_MEMBER(md4, $enabled_digests)
if test "$found" = "1" ; then
GCRYPT_DIGESTS="$GCRYPT_DIGESTS md4.lo"
diff --git a/src/cipher.h b/src/cipher.h
index 26ffddc..cd981b3 100644
--- a/src/cipher.h
+++ b/src/cipher.h
@@ -246,6 +246,7 @@ extern gcry_md_spec_t _gcry_digest_spec_crc24_rfc2440;
extern gcry_md_spec_t _gcry_digest_spec_gost3411_94;
extern gcry_md_spec_t _gcry_digest_spec_stribog_256;
extern gcry_md_spec_t _gcry_digest_spec_stribog_512;
+extern gcry_md_spec_t _gcry_digest_spec_md2;
extern gcry_md_spec_t _gcry_digest_spec_md4;
extern gcry_md_spec_t _gcry_digest_spec_md5;
extern gcry_md_spec_t _gcry_digest_spec_rmd160;
diff --git a/tests/basic.c b/tests/basic.c
index e21e055..5abedb3 100644
--- a/tests/basic.c
+++ b/tests/basic.c
@@ -3784,6 +3784,12 @@ check_digests (void)
const char *expect;
} algos[] =
{
+ { GCRY_MD_MD2, "",
+ "\x83\x50\xe5\xa3\xe2\x4c\x15\x3d\xf2\x27\x5c\x9f\x80\x69\x27\x73" },
+ { GCRY_MD_MD2, "a",
+ "\x32\xec\x01\xec\x4a\x6d\xac\x72\xc0\xab\x96\xfb\x34\xc0\xb5\xd1"},
+ { GCRY_MD_MD2, "message digest",
+ "\xab\x4f\x49\x6b\xfb\x2a\x53\x0b\x21\x9f\xf3\x30\x31\xfe\x06\xb0"},
{ GCRY_MD_MD4, "",
"\x31\xD6\xCF\xE0\xD1\x6A\xE9\x31\xB7\x3C\x59\xD7\xE0\xC0\x89\xC0" },
{ GCRY_MD_MD4, "a",
--
1.9.0
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