--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libtomcrypt/src/pk/dsa/dsa_set.c	Fri Feb 09 21:44:05 2018 +0800
@@ -0,0 +1,112 @@
+/* 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.
+ */
+#include "tomcrypt.h"
+
+
+#ifdef LTC_MDSA
+
+/**
+  Import DSA's p, q & g from raw numbers
+  @param p       DSA's p  in binary representation
+  @param plen    The length of p
+  @param q       DSA's q  in binary representation
+  @param qlen    The length of q
+  @param g       DSA's g  in binary representation
+  @param glen    The length of g
+  @param key     [out] the destination for the imported key
+  @return CRYPT_OK if successful.
+*/
+int dsa_set_pqg(const unsigned char *p,  unsigned long plen,
+                const unsigned char *q,  unsigned long qlen,
+                const unsigned char *g,  unsigned long glen,
+                dsa_key *key)
+{
+   int err, stat;
+
+   LTC_ARGCHK(p           != NULL);
+   LTC_ARGCHK(q           != NULL);
+   LTC_ARGCHK(g           != NULL);
+   LTC_ARGCHK(key         != 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_unsigned_bin(key->p, (unsigned char *)p , plen)) != CRYPT_OK) { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->g, (unsigned char *)g , glen)) != CRYPT_OK) { goto LBL_ERR; }
+   if ((err = mp_read_unsigned_bin(key->q, (unsigned char *)q , qlen)) != CRYPT_OK) { goto LBL_ERR; }
+
+   key->qord = mp_unsigned_bin_size(key->q);
+
+   /* do only a quick validation, without primality testing */
+   if ((err = dsa_int_validate_pqg(key, &stat)) != CRYPT_OK)                        { goto LBL_ERR; }
+   if (stat == 0) {
+      err = CRYPT_INVALID_PACKET;
+      goto LBL_ERR;
+   }
+
+   return CRYPT_OK;
+
+LBL_ERR:
+   dsa_free(key);
+   return err;
+}
+
+/**
+  Import DSA public or private key-part from raw numbers
+
+     NB: The p, q & g parts must be set beforehand
+
+  @param in      The key-part to import, either public or private.
+  @param inlen   The key-part's length
+  @param type    Which type of key (PK_PRIVATE or PK_PUBLIC)
+  @param key     [out] the destination for the imported key
+  @return CRYPT_OK if successful.
+*/
+int dsa_set_key(const unsigned char *in, unsigned long inlen, int type, dsa_key *key)
+{
+   int err, stat = 0;
+
+   LTC_ARGCHK(key         != NULL);
+   LTC_ARGCHK(key->x      != NULL);
+   LTC_ARGCHK(key->y      != NULL);
+   LTC_ARGCHK(key->p      != NULL);
+   LTC_ARGCHK(key->g      != NULL);
+   LTC_ARGCHK(key->q      != NULL);
+   LTC_ARGCHK(ltc_mp.name != NULL);
+
+   if (type == PK_PRIVATE) {
+      key->type = PK_PRIVATE;
+      if ((err = mp_read_unsigned_bin(key->x, (unsigned char *)in, inlen)) != CRYPT_OK) { goto LBL_ERR; }
+      if ((err = mp_exptmod(key->g, key->x, key->p, key->y)) != CRYPT_OK)               { goto LBL_ERR; }
+   }
+   else {
+      key->type = PK_PUBLIC;
+      if ((err = mp_read_unsigned_bin(key->y, (unsigned char *)in, inlen)) != CRYPT_OK) { goto LBL_ERR; }
+   }
+
+   if ((err = dsa_int_validate_xy(key, &stat)) != CRYPT_OK)                             { goto LBL_ERR; }
+   if (stat == 0) {
+      err = CRYPT_INVALID_PACKET;
+      goto LBL_ERR;
+   }
+
+   return CRYPT_OK;
+
+LBL_ERR:
+   dsa_free(key);
+   return err;
+}
+
+#endif
+
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */