commit files needed for zpm-fetchurl

[zpackage] / libtomcrypt / src / pk / ecc / ecc_ansi_x963_export.c

diff --git a/libtomcrypt/src/pk/ecc/ecc_ansi_x963_export.c b/libtomcrypt/src/pk/ecc/ecc_ansi_x963_export.c
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+++ b/libtomcrypt/src/pk/ecc/ecc_ansi_x963_export.c
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+/* 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.
+ */
+
+/* Implements ECC over Z/pZ for curve y^2 = x^3 - 3x + b
+ *
+ * All curves taken from NIST recommendation paper of July 1999
+ * Available at http://csrc.nist.gov/cryptval/dss.htm
+ */
+#include "tomcrypt.h"
+
+/**
+  @file ecc_ansi_x963_export.c
+  ECC Crypto, Tom St Denis
+*/
+
+#ifdef LTC_MECC
+
+/** ECC X9.63 (Sec. 4.3.6) uncompressed export
+  @param key     Key to export
+  @param out     [out] destination of export
+  @param outlen  [in/out]  Length of destination and final output size
+  Return CRYPT_OK on success
+*/
+int ecc_ansi_x963_export(ecc_key *key, unsigned char *out, unsigned long *outlen)
+{
+   unsigned char buf[ECC_BUF_SIZE];
+   unsigned long numlen, xlen, ylen;
+
+   LTC_ARGCHK(key    != NULL);
+   LTC_ARGCHK(outlen != NULL);
+
+   if (ltc_ecc_is_valid_idx(key->idx) == 0) {
+      return CRYPT_INVALID_ARG;
+   }
+   numlen = key->dp->size;
+   xlen = mp_unsigned_bin_size(key->pubkey.x);
+   ylen = mp_unsigned_bin_size(key->pubkey.y);
+
+   if (xlen > numlen || ylen > numlen || sizeof(buf) < numlen) {
+      return CRYPT_BUFFER_OVERFLOW;
+   }
+
+   if (*outlen < (1 + 2*numlen)) {
+      *outlen = 1 + 2*numlen;
+      return CRYPT_BUFFER_OVERFLOW;
+   }
+
+   LTC_ARGCHK(out    != NULL);
+
+   /* store byte 0x04 */
+   out[0] = 0x04;
+
+   /* pad and store x */
+   zeromem(buf, sizeof(buf));
+   mp_to_unsigned_bin(key->pubkey.x, buf + (numlen - xlen));
+   XMEMCPY(out+1, buf, numlen);
+
+   /* pad and store y */
+   zeromem(buf, sizeof(buf));
+   mp_to_unsigned_bin(key->pubkey.y, buf + (numlen - ylen));
+   XMEMCPY(out+1+numlen, buf, numlen);
+
+   *outlen = 1 + 2*numlen;
+   return CRYPT_OK;
+}
+
+#endif
+
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */