adding dsa_import_radix

src/headers/tomcrypt_pk.h

@@ -430,6 +430,7 @@ int dsa_decrypt_key(const unsigned char *in,  unsigned long  inlen,
                           unsigned char *out, unsigned long *outlen,
                           dsa_key *key);
 
+int dsa_import_radix(int radix, char *p, char *q, char *g, char *x, char *y, dsa_key *key);
 int dsa_import(const unsigned char *in, unsigned long inlen, dsa_key *key);
 int dsa_export(unsigned char *out, unsigned long *outlen, int type, dsa_key *key);
 int dsa_verify_key(dsa_key *key, int *stat);

src/pk/dsa/dsa_import_radix.c

@@ -0,0 +1,67 @@
+/* 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, [email protected], http://libtom.org
+ */
+#include "tomcrypt.h"
+
+/**
+  Import DSA public or private key from raw numbers
+  @param radix   the radix the numbers are represented in (2-64, 16 = hexadecimal)
+  @param p       DSA's p  in radix representation
+  @param q       DSA's q  in radix representation
+  @param g       DSA's g  in radix representation
+  @param x       DSA's x  in radix representation (only private key, NULL for public key)
+  @param y       DSA's y  in radix representation
+  @param key     [out] the destination for the imported key
+  @return CRYPT_OK if successful, upon error allocated memory is freed
+*/
+
+#ifdef LTC_MDSA
+
+int dsa_import_radix(int radix, char *p, char *q, char *g, char *x, char *y, dsa_key *key)
+{
+   int err;
+
+   LTC_ARGCHK(p != NULL);
+   LTC_ARGCHK(q != NULL);
+   LTC_ARGCHK(g != NULL);
+   LTC_ARGCHK(y != NULL);
+   LTC_ARGCHK(ltc_mp.name != NULL);
+
+   /* init key */
+   err = mp_init_multi(&key->p, &key->g, &key->q, &key->x, &key->y, NULL);
+   if (err != CRYPT_OK) return err;
+   
+   if ((err = mp_read_radix(key->p , p , radix)) != CRYPT_OK) { goto LBL_ERR; }
+   if ((err = mp_read_radix(key->q , q , radix)) != CRYPT_OK) { goto LBL_ERR; }
+   if ((err = mp_read_radix(key->g , g , radix)) != CRYPT_OK) { goto LBL_ERR; }
+   if ((err = mp_read_radix(key->y , y , radix)) != CRYPT_OK) { goto LBL_ERR; }
+   if (x && strlen(x) > 0) {
+      key->type = PK_PRIVATE;
+      if ((err = mp_read_radix(key->x , x , radix)) != CRYPT_OK) { goto LBL_ERR; }
+   }
+   else {
+      key->type = PK_PUBLIC;
+   }
+
+   key->qord = mp_unsigned_bin_size(key->q);
+
+   if (key->qord >= LTC_MDSA_MAX_GROUP || key->qord <= 15 ||
+      (unsigned long)key->qord >= mp_unsigned_bin_size(key->p) || (mp_unsigned_bin_size(key->p) - key->qord) >= LTC_MDSA_DELTA) {
+      err = CRYPT_INVALID_PACKET;
+      goto LBL_ERR;
+   }
+   return CRYPT_OK;
+
+LBL_ERR:
+   mp_clear_multi(key->p, key->g, key->q, key->x, key->y, NULL);
+   return err;
+}
+
+#endif