New file.

Rev: src/nettle/der2rsa.c:1.1
Rev: src/nettle/testsuite/pkcs1-conv-test:1.1

1 files changed, 137 insertions, 0 deletions

diff --git a/der2rsa.c b/der2rsa.c
new file mode 100644
index 00000000..9d8b437f
--- /dev/null
+++ b/der2rsa.c
@@ -0,0 +1,137 @@
+/* der2rsa.c
+ *
+ * Decoding of keys in PKCS#1 format.
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2005 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 WITH_PUBLIC_KEY
+
+#include "rsa.h"
+
+#include "bignum.h"
+#include "asn1.h"
+
+#define GET(i, x, l)					\
+(asn1_der_iterator_next((i)) == ASN1_ITERATOR_PRIMITIVE	\
+ && (i)->type == ASN1_INTEGER				\
+ && asn1_der_get_bignum((i), (x), (l))			\
+ && mpz_sgn((x)) > 0)
+
+int
+rsa_public_key_from_der_iterator(struct rsa_public_key *pub,
+				 unsigned limit,
+				 struct asn1_der_iterator *i)
+{
+  /* RSAPublicKey ::= SEQUENCE {
+         modulus           INTEGER,  -- n
+	 publicExponent    INTEGER   -- e
+      }
+  */
+
+  return (i->type == ASN1_SEQUENCE
+	  && asn1_der_decode_constructed_last(i) == ASN1_ITERATOR_PRIMITIVE
+	  && asn1_der_get_bignum(i, pub->n, limit) 
+	  && mpz_sgn(pub->n) > 0
+	  && GET(i, pub->e, limit)
+	  && asn1_der_iterator_next(i) == ASN1_ITERATOR_END
+	  && rsa_public_key_prepare(pub));
+}
+
+int
+rsa_private_key_from_der_iterator(struct rsa_public_key *pub,
+				  struct rsa_private_key *priv,
+				  unsigned limit,
+				  struct asn1_der_iterator *i)
+{
+  /* RSAPrivateKey ::= SEQUENCE {
+         version           Version,
+	 modulus           INTEGER,  -- n
+	 publicExponent    INTEGER,  -- e
+	 privateExponent   INTEGER,  -- d
+	 prime1            INTEGER,  -- p
+	 prime2            INTEGER,  -- q
+	 exponent1         INTEGER,  -- d mod (p-1)
+	 exponent2         INTEGER,  -- d mod (q-1)
+	 coefficient       INTEGER,  -- (inverse of q) mod p
+	 otherPrimeInfos   OtherPrimeInfos OPTIONAL
+    }
+  */
+
+  uint32_t version;
+  
+  if (i->type != ASN1_SEQUENCE)
+    return 0;
+
+  if (asn1_der_decode_constructed_last(i) == ASN1_ITERATOR_PRIMITIVE
+      && i->type == ASN1_INTEGER
+      && asn1_der_get_uint32(i, &version)
+      && version <= 1
+      && GET(i, pub->n, limit)
+      && GET(i, pub->e, limit)
+      && rsa_public_key_prepare(pub)
+      && GET(i, priv->d, limit)
+      && GET(i, priv->p, limit)
+      && GET(i, priv->q, limit)
+      && GET(i, priv->a, limit)
+      && GET(i, priv->b, limit)
+      && GET(i, priv->c, limit)
+      && rsa_private_key_prepare(priv))
+    {
+      if (version == 1)
+	{
+	  /* otherPrimeInfos must be present. We ignore the contents */
+	  if (!(asn1_der_iterator_next(i) == ASN1_ITERATOR_CONSTRUCTED
+		&& i->type == ASN1_SEQUENCE))
+	    return 0;
+	}
+
+      return (asn1_der_iterator_next(i) == ASN1_ITERATOR_END);
+    }
+  
+  return 0;
+}
+
+int
+rsa_keypair_from_der(struct rsa_public_key *pub,
+		     struct rsa_private_key *priv,
+		     unsigned limit, 
+		     unsigned length, const uint8_t *data)
+{
+  struct asn1_der_iterator i;
+  enum asn1_iterator_result res;
+
+  res = asn1_der_iterator_first(&i, length, data);
+
+  if (res != ASN1_ITERATOR_CONSTRUCTED)
+    return 0;
+
+  if (priv)
+    return rsa_private_key_from_der_iterator(pub, priv, limit, &i);
+  else
+    return rsa_public_key_from_der_iterator(pub, limit, &i);    
+}
+
+#endif /* WITH_PUBLIC_KEY */