diff libtomcrypt/src/pk/dsa/dsa_generate_key.c @ 1471:6dba84798cd5

Update to libtomcrypt 1.18.1, merged with Dropbear changes
author Matt Johnston <matt@ucc.asn.au>
date Fri, 09 Feb 2018 21:44:05 +0800
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libtomcrypt/src/pk/dsa/dsa_generate_key.c	Fri Feb 09 21:44:05 2018 +0800
@@ -0,0 +1,47 @@
+/* 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"
+
+/**
+   @file dsa_make_key.c
+   DSA implementation, generate a DSA key
+*/
+
+#ifdef LTC_MDSA
+
+/**
+  Create a DSA key
+  @param prng          An active PRNG state
+  @param wprng         The index of the PRNG desired
+  @param key           [in/out] Where to store the created key
+  @return CRYPT_OK if successful.
+*/
+int dsa_generate_key(prng_state *prng, int wprng, dsa_key *key)
+{
+  int err;
+
+  LTC_ARGCHK(key         != NULL);
+  LTC_ARGCHK(ltc_mp.name != NULL);
+
+  /* so now we have our DH structure, generator g, order q, modulus p
+     Now we need a random exponent [mod q] and it's power g^x mod p
+   */
+  /* private key x should be from range: 1 <= x <= q-1 (see FIPS 186-4 B.1.2) */
+  if ((err = rand_bn_upto(key->x, key->q, prng, wprng)) != CRYPT_OK)          { return err; }
+  if ((err = mp_exptmod(key->g, key->x, key->p, key->y)) != CRYPT_OK)            { return err; }
+  key->type = PK_PRIVATE;
+
+  return CRYPT_OK;
+}
+
+#endif
+
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */