added wrapper for EVP_BPE_scrypt

Author: harrybrwn

scrypt.go

@@ -0,0 +1,37 @@
+//go:build !cmd_go_bootstrap
+
+package openssl
+
+// #include "goopenssl.h"
+import "C"
+import (
+	"unsafe"
+)
+
+func Scrypt(password string, salt []byte, N, r, p, maxmem, keylen uint64) ([]byte, error) {
+	cpassword := C.CString(password)
+	defer C.free((unsafe.Pointer)(cpassword))
+
+	csalt := C.CBytes(salt)
+	defer C.free((unsafe.Pointer)(csalt))
+
+	key := C.malloc(C.size_t(keylen))
+	defer C.free(key)
+
+	res := C.go_openssl_EVP_PBE_scrypt(
+		cpassword,
+		C.size_t(len(password)),
+		(*C.uchar)(csalt),
+		C.size_t(len(salt)),
+		C.uint64_t(N),
+		C.uint64_t(r),
+		C.uint64_t(p),
+		C.uint64_t(maxmem),
+		(*C.uchar)(key),
+		C.size_t(keylen),
+	)
+	if res != 1 {
+		return nil, newOpenSSLError("EVP_PBE_scrypt")
+	}
+	return C.GoBytes(key, C.int(keylen)), nil
+}

scrypt_test.go

@@ -0,0 +1,36 @@
+//go:build !cmd_go_bootstrap
+
+package openssl_test
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/golang-fips/openssl/v2"
+)
+
+func TestScrypt(t *testing.T) {
+	hash, err := openssl.Scrypt("testpass01", []byte("abc123"), 1<<14, 8, 1, 32<<20, 64)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(hash) == 0 {
+		t.Error("zero length hash")
+	}
+	hexhash := fmt.Sprintf("%x", hash)
+	exp := "e6a3569950bf90e88d2f114c3d43f2d103cf3c13cf1579095e88ff5b3b3eb379cad31d26aa533e0f32c10666bbcc9c1cac2775a8a60d55d55d63c401927e905e"
+	if hexhash != exp {
+		t.Errorf("expected %q, got %q", exp, hexhash)
+	}
+}
+
+func TestScrypt_Err(t *testing.T) {
+	_, err := openssl.Scrypt("testpass01", []byte("abc123"), 1<<14, 0, 0, 32<<20, 64)
+	if err == nil {
+		t.Error("expected an error when using zeros for r and p")
+	}
+	_, err = openssl.Scrypt("x", []byte("y"), 1<<14, 8, 1, 1<<20, 32)
+	if err == nil {
+		t.Error("expected memory limit error")
+	}
+}

shims.h

@@ -410,4 +410,4 @@ DEFINEFUNC_3_0(int, EVP_KDF_CTX_set_params, (GO_EVP_KDF_CTX_PTR ctx, const GO_OS
 DEFINEFUNC_3_0(void, EVP_KDF_CTX_free, (GO_EVP_KDF_CTX_PTR ctx), (ctx)) \
 DEFINEFUNC_3_0(size_t, EVP_KDF_CTX_get_kdf_size, (GO_EVP_KDF_CTX_PTR ctx), (ctx)) \
 DEFINEFUNC_3_0(int, EVP_KDF_derive, (GO_EVP_KDF_CTX_PTR ctx, unsigned char *key, size_t keylen, const GO_OSSL_PARAM_PTR params), (ctx, key, keylen, params)) \
-
+DEFINEFUNC_1_1_1(int, EVP_PBE_scrypt, (const char *pass, size_t passlen, const unsigned char *salt, size_t saltlen, uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem, unsigned char *key, size_t keylen), (pass, passlen, salt, saltlen, N, r, p, maxmem, key, keylen))