1 files changed, 89 insertions, 0 deletions
diff --git a/libtomcrypt/src/pk/dsa/dsa_import.c b/libtomcrypt/src/pk/dsa/dsa_import.c
new file mode 100644
index 0000000..e81bac8
--- /dev/null
+++ b/libtomcrypt/src/pk/dsa/dsa_import.c
@@ -0,0 +1,89 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.org
+ */
+#include "tomcrypt.h"
+
+/**
+   @file dsa_import.c
+   DSA implementation, import a DSA key, Tom St Denis
+*/
+
+#ifdef MDSA
+
+/**
+   Import a DSA key 
+   @param in       The binary packet to import from
+   @param inlen    The length of the binary packet
+   @param key      [out] Where to store the imported key
+   @return CRYPT_OK if successful, upon error this function will free all allocated memory
+*/
+int dsa_import(const unsigned char *in, unsigned long inlen, dsa_key *key)
+{
+   unsigned char flags[1];
+   int           err;
+
+   LTC_ARGCHK(in  != NULL);
+   LTC_ARGCHK(key != NULL);
+
+   /* init key */
+   if (mp_init_multi(&key->p, &key->g, &key->q, &key->x, &key->y, NULL) != MP_OKAY) {
+      return CRYPT_MEM;
+   }
+
+   /* get key type */
+   if ((err = der_decode_sequence_multi(in, inlen,
+                                  LTC_ASN1_BIT_STRING, 1UL, flags,
+                                  LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) {
+      goto error;
+   }
+
+   if (flags[0] == 1) {
+      if ((err = der_decode_sequence_multi(in, inlen,
+                                 LTC_ASN1_BIT_STRING,   1UL, flags,
+                                 LTC_ASN1_INTEGER,      1UL, &key->g,
+                                 LTC_ASN1_INTEGER,      1UL, &key->p,
+                                 LTC_ASN1_INTEGER,      1UL, &key->q,
+                                 LTC_ASN1_INTEGER,      1UL, &key->y,
+                                 LTC_ASN1_INTEGER,      1UL, &key->x,
+                                 LTC_ASN1_EOL,          0UL, NULL)) != CRYPT_OK) {
+         goto error;
+      }
+      key->type = PK_PRIVATE;
+   } else {
+      if ((err = der_decode_sequence_multi(in, inlen,
+                                 LTC_ASN1_BIT_STRING,   1UL, flags,
+                                 LTC_ASN1_INTEGER,      1UL, &key->g,
+                                 LTC_ASN1_INTEGER,      1UL, &key->p,
+                                 LTC_ASN1_INTEGER,      1UL, &key->q,
+                                 LTC_ASN1_INTEGER,      1UL, &key->y,
+                                 LTC_ASN1_EOL,          0UL, NULL)) != CRYPT_OK) {
+         goto error;
+      }
+      key->type = PK_PUBLIC;
+  }
+  key->qord = mp_unsigned_bin_size(&key->q);
+
+  if (key->qord >= MDSA_MAX_GROUP || key->qord <= 15 ||
+      key->qord >= mp_unsigned_bin_size(&key->p) || (mp_unsigned_bin_size(&key->p) - key->qord) >= MDSA_DELTA) {
+      err = CRYPT_INVALID_PACKET;
+      goto error;
+   }
+
+  return CRYPT_OK;
+error: 
+   mp_clear_multi(&key->p, &key->g, &key->q, &key->x, &key->y, NULL);
+   return err;
+}
+
+#endif
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/dsa/dsa_import.c,v $ */
+/* $Revision: 1.7 $ */
+/* $Date: 2005/06/08 23:31:17 $ */