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-rw-r--r--libtomcrypt/src/pk/dsa/dsa_generate_key.c47
1 files changed, 47 insertions, 0 deletions
diff --git a/libtomcrypt/src/pk/dsa/dsa_generate_key.c b/libtomcrypt/src/pk/dsa/dsa_generate_key.c
new file mode 100644
index 0000000..18b2df6
--- /dev/null
+++ b/libtomcrypt/src/pk/dsa/dsa_generate_key.c
@@ -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: $Format:%ai$ */