[dev.boringcrypto] crypto/ecdsa: use BoringCrypto

Change-Id: I108e0a527bddd673b16582d206e0697341d0a0ea
Reviewed-on: https://go-review.googlesource.com/55478
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/src/crypto/internal/boring/boring.go b/src/crypto/internal/boring/boring.go
index 615b1efadc..bf1509122d 100644
--- a/src/crypto/internal/boring/boring.go
+++ b/src/crypto/internal/boring/boring.go
@@ -9,6 +9,7 @@ package boring
 
 // #include "goboringcrypto.h"
 import "C"
+import "math/big"
 
 const available = true
 
@@ -41,3 +42,14 @@ func UnreachableExceptTests() {
 type fail string
 
 func (e fail) Error() string { return "boringcrypto: " + string(e) + " failed" }
+
+func bigToBN(x *big.Int) *C.GO_BIGNUM {
+	raw := x.Bytes()
+	return C._goboringcrypto_BN_bin2bn(base(raw), C.size_t(len(raw)), nil)
+}
+
+func bnToBig(bn *C.GO_BIGNUM) *big.Int {
+	raw := make([]byte, C._goboringcrypto_BN_num_bytes(bn))
+	n := C._goboringcrypto_BN_bn2bin(bn, base(raw))
+	return new(big.Int).SetBytes(raw[:n])
+}