* rsa_sha1.c: New file, PKCS#1 rsa-sha1 signatures.

* rsa_md5.c: New file, PKCS#1 rsa-md5 signatures.

Rev: src/nettle/rsa_md5.c:1.1
Rev: src/nettle/rsa_sha1.c:1.1

diff --git a/rsa_md5.c b/rsa_md5.c
new file mode 100644 (file)
index 0000000..41e5c71
--- /dev/null
+++ b/rsa_md5.c
@@ -0,0 +1,139 @@
+/* rsa_md5.c
+ *
+ * Signatures using RSA and MD5.
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2001 Niels Möller
+ *  
+ * The nettle library 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.
+ * 
+ * The nettle library 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 the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#if HAVE_LIBGMP
+
+#include "rsa.h"
+
+#include "bignum.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+/* Forward declarations */
+static void
+pkcs1_encode_md5(mpz_t m, unsigned length, struct md5_ctx *hash);
+
+void
+rsa_md5_sign(struct rsa_private_key *key,
+             struct md5_ctx *hash,
+             uint8_t *signature)
+{
+  mpz_t m;
+  mpz_init(m);
+
+  assert(key->pub.size >= 45);
+
+  pkcs1_encode_md5(m, key->pub.size - 1, hash);
+
+  rsa_compute_root(key, m, m);
+
+  nettle_mpz_get_str_256(key->pub.size, signature, m);
+
+  mpz_clear(m);
+}
+
+int
+rsa_md5_verify(struct rsa_public_key *key,
+               struct md5_ctx *hash,
+               const uint8_t *signature)
+{
+  int res;
+  
+  mpz_t m;
+  mpz_t s;
+
+  mpz_init(m);
+  
+  nettle_mpz_init_set_str_256(s, key->size, signature);
+  mpz_powm(s, s, key->e, key->n);
+
+  /* FIXME: Is it cheaper to convert s to a string and check that? */
+  pkcs1_encode_md5(m, key->size - 1, hash);
+  res = !mpz_cmp(m, s);
+
+  mpz_clear(m); mpz_clear(s);
+
+  return res;
+}
+
+/* From pkcs-1v2
+ *
+ *   md5 OBJECT IDENTIFIER ::=
+ *     {iso(1) member-body(2) US(840) rsadsi(113549) digestAlgorithm(2) 5}
+ *
+ * The parameters part of the algorithm identifier is NULL:
+ *
+ *   md5Identifier ::= AlgorithmIdentifier {md5, NULL}
+ */
+
+static const uint8_t md5_prefix[] =
+{
+  /* 18 octets prefix, 16 octets hash, 34 total. */
+  0x30,       32, /* SEQUENCE */
+    0x30,     12, /* SEQUENCE */
+      0x06,    8, /* OBJECT IDENTIFIER */
+       0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05,
+      0x05,    0, /* NULL */
+    0x04,     16  /* OCTET STRING */
+      /* Here comes the raw hash value */
+};
+
+static void
+pkcs1_encode_md5(mpz_t m, unsigned length, struct md5_ctx *hash)
+{
+  uint8_t *em = alloca(length);
+  unsigned i;
+
+  assert(length >= MD5_DIGEST_SIZE);
+
+  i = length - MD5_DIGEST_SIZE;
+  
+  md5_final(hash);
+  md5_digest(hash, MD5_DIGEST_SIZE, em + i);
+  md5_init(hash);
+
+  assert(i >= sizeof(md5_prefix));
+
+  i -= sizeof(md5_prefix);
+  memcpy(em + i, md5_prefix, sizeof(md5_prefix));
+
+  assert(i);
+  em[--i] = 0;
+
+  assert(i >= 9);
+
+  em[0] = 1;
+  memset(em + 1, 0xff, i - 1);
+
+  nettle_mpz_set_str_256(m, length, em);
+}
+
+#endif /* HAVE_LIBGMP */

diff --git a/rsa_sha1.c b/rsa_sha1.c
new file mode 100644 (file)
index 0000000..be69399
--- /dev/null
+++ b/rsa_sha1.c
@@ -0,0 +1,141 @@
+/* rsa_sha1.c
+ *
+ * Signatures using RSA and SHA1.
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2001 Niels Möller
+ *  
+ * The nettle library 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.
+ * 
+ * The nettle library 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 the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#if HAVE_LIBGMP
+
+#include "rsa.h"
+
+#include "bignum.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+/* Forward declarations */
+static void
+pkcs1_encode_sha1(mpz_t m, unsigned length, struct sha1_ctx *hash);
+
+void
+rsa_sha1_sign(struct rsa_private_key *key,
+              struct sha1_ctx *hash,
+              uint8_t *signature)
+{
+  mpz_t m;
+  mpz_init(m);
+
+  assert(key->pub.size >= 45);
+
+  pkcs1_encode_sha1(m, key->pub.size - 1, hash);
+
+  rsa_compute_root(key, m, m);
+
+  nettle_mpz_get_str_256(key->pub.size, signature, m);
+
+  mpz_clear(m);
+}
+
+int
+rsa_sha1_verify(struct rsa_public_key *key,
+                struct sha1_ctx *hash,
+                const uint8_t *signature)
+{
+  int res;
+  
+  mpz_t m;
+  mpz_t s;
+
+  mpz_init(m);
+  
+  nettle_mpz_init_set_str_256(s, key->size, signature);
+  mpz_powm(s, s, key->e, key->n);
+
+  /* FIXME: Is it cheaper to convert s to a string and check that? */
+  pkcs1_encode_sha1(m, key->size - 1, hash);
+  res = !mpz_cmp(m, s);
+
+  mpz_clear(m); mpz_clear(s);
+
+  return res;
+}
+
+/* From pkcs-1v2
+ *
+ *   id-sha1 OBJECT IDENTIFIER ::=
+ *     {iso(1) identified-organization(3) oiw(14) secsig(3)
+ *      algorithms(2) 26}
+ *   
+ *   The default hash function is SHA-1: 
+ *   sha1Identifier ::= AlgorithmIdentifier {id-sha1, NULL}
+ */
+
+static const uint8_t sha1_prefix[] =
+{
+  /* 15 octets prefix, 20 octets hash, total 35 */
+  0x30,       33, /* SEQUENCE */
+    0x30,      9, /* SEQUENCE */
+      0x06,    5, /* OBJECT IDENTIFIER */
+         0x2b, 0x0e, 0x03, 0x02, 0x1a,
+      0x05,    0, /* NULL */
+    0x04,     20  /* OCTET STRING */
+      /* Here comes the raw hash value */
+};
+    
+
+
+static void
+pkcs1_encode_sha1(mpz_t m, unsigned length, struct sha1_ctx *hash)
+{
+  uint8_t *em = alloca(length);
+  unsigned i;
+
+  assert(length >= SHA1_DIGEST_SIZE);
+
+  i = length - SHA1_DIGEST_SIZE;
+  
+  sha1_final(hash);
+  sha1_digest(hash, SHA1_DIGEST_SIZE, em + i);
+  sha1_init(hash);
+
+  assert(i >= sizeof(sha1_prefix));
+
+  i -= sizeof(sha1_prefix);
+  memcpy(em + i, sha1_prefix, sizeof(sha1_prefix));
+
+  assert(i);
+  em[--i] = 0;
+
+  assert(i >= 9);
+
+  em[0] = 1;
+  memset(em + 1, 0xff, i - 1);
+
+  nettle_mpz_set_str_256(m, length, em);
+}
+
+#endif /* HAVE_LIBGMP */