New "i62" code for big integers with 64x64->128 opcodes; also improved "i31" modular...

[BearSSL] / src / rsa / rsa_i62_pkcs1_vrfy.c

diff --git a/src/rsa/rsa_i62_pkcs1_vrfy.c b/src/rsa/rsa_i62_pkcs1_vrfy.c
new file mode 100644 (file)
index 0000000..6519161
--- /dev/null
+++ b/src/rsa/rsa_i62_pkcs1_vrfy.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2017 Thomas Pornin <pornin@bolet.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining 
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be 
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "inner.h"
+
+#if BR_INT128 || BR_UMUL128
+
+/* see bearssl_rsa.h */
+uint32_t
+br_rsa_i62_pkcs1_vrfy(const unsigned char *x, size_t xlen,
+       const unsigned char *hash_oid, size_t hash_len,
+       const br_rsa_public_key *pk, unsigned char *hash_out)
+{
+       unsigned char sig[BR_MAX_RSA_SIZE >> 3];
+
+       if (xlen > (sizeof sig)) {
+               return 0;
+       }
+       memcpy(sig, x, xlen);
+       if (!br_rsa_i62_public(sig, xlen, pk)) {
+               return 0;
+       }
+       return br_rsa_pkcs1_sig_unpad(sig, xlen, hash_oid, hash_len, hash_out);
+}
+
+/* see bearssl_rsa.h */
+br_rsa_pkcs1_vrfy
+br_rsa_i62_pkcs1_vrfy_get(void)
+{
+       return &br_rsa_i62_pkcs1_vrfy;
+}
+
+#else
+
+/* see bearssl_rsa.h */
+br_rsa_pkcs1_vrfy
+br_rsa_i62_pkcs1_vrfy_get(void)
+{
+       return 0;
+}
+
+#endif