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Diffstat (limited to 'libtomcrypt/src/pk/ecc/ecc_ansi_x963_import.c')
-rw-r--r--libtomcrypt/src/pk/ecc/ecc_ansi_x963_import.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/libtomcrypt/src/pk/ecc/ecc_ansi_x963_import.c b/libtomcrypt/src/pk/ecc/ecc_ansi_x963_import.c
new file mode 100644
index 0000000..e92f5f4
--- /dev/null
+++ b/libtomcrypt/src/pk/ecc/ecc_ansi_x963_import.c
@@ -0,0 +1,104 @@
+/* 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, tomstdenis@gmail.com, http://libtomcrypt.com
+ */
+
+/* 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_import.c
+ ECC Crypto, Tom St Denis
+*/
+
+#ifdef MECC
+
+/** Import an ANSI X9.63 format public key
+ @param in The input data to read
+ @param inlen The length of the input data
+ @param key [out] destination to store imported key \
+*/
+int ecc_ansi_x963_import(const unsigned char *in, unsigned long inlen, ecc_key *key)
+{
+ return ecc_ansi_x963_import_ex(in, inlen, key, NULL);
+}
+
+int ecc_ansi_x963_import_ex(const unsigned char *in, unsigned long inlen, ecc_key *key, ltc_ecc_set_type *dp)
+{
+ int x, err;
+
+ LTC_ARGCHK(in != NULL);
+ LTC_ARGCHK(key != NULL);
+
+ /* must be odd */
+ if ((inlen & 1) == 0) {
+ return CRYPT_INVALID_ARG;
+ }
+
+ /* init key */
+ if (mp_init_multi(&key->pubkey.x, &key->pubkey.y, &key->pubkey.z, &key->k, NULL) != CRYPT_OK) {
+ return CRYPT_MEM;
+ }
+
+ /* check for 4, 6 or 7 */
+ if (in[0] != 4 && in[0] != 6 && in[0] != 7) {
+ err = CRYPT_INVALID_PACKET;
+ goto error;
+ }
+
+ /* read data */
+ if ((err = mp_read_unsigned_bin(key->pubkey.x, (unsigned char *)in+1, (inlen-1)>>1)) != CRYPT_OK) {
+ goto error;
+ }
+
+ if ((err = mp_read_unsigned_bin(key->pubkey.y, (unsigned char *)in+1+((inlen-1)>>1), (inlen-1)>>1)) != CRYPT_OK) {
+ goto error;
+ }
+ if ((err = mp_set(key->pubkey.z, 1)) != CRYPT_OK) { goto error; }
+
+ if (dp == NULL) {
+ /* determine the idx */
+ for (x = 0; ltc_ecc_sets[x].size != 0; x++) {
+ if ((unsigned)ltc_ecc_sets[x].size >= ((inlen-1)>>1)) {
+ break;
+ }
+ }
+ if (ltc_ecc_sets[x].size == 0) {
+ err = CRYPT_INVALID_PACKET;
+ goto error;
+ }
+ /* set the idx */
+ key->idx = x;
+ key->dp = &ltc_ecc_sets[x];
+ } else {
+ if (((inlen-1)>>1) != (unsigned long) dp->size) {
+ err = CRYPT_INVALID_PACKET;
+ goto error;
+ }
+ key->idx = -1;
+ key->dp = dp;
+ }
+ key->type = PK_PUBLIC;
+
+ /* we're done */
+ return CRYPT_OK;
+error:
+ mp_clear_multi(key->pubkey.x, key->pubkey.y, key->pubkey.z, key->k, NULL);
+ return err;
+}
+
+#endif
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/ecc/ecc_ansi_x963_import.c,v $ */
+/* $Revision: 1.9 $ */
+/* $Date: 2006/12/04 22:17:46 $ */