From d8d1347863d8a9abeef8f3173fa53b61ec915c05 Mon Sep 17 00:00:00 2001
From: Roy Crihfield <roy@manteia.ltd>
Date: Wed, 7 Jun 2023 00:15:31 +0800
Subject: [PATCH] conditionally link against geth's libsecp256k1

---
 restricted/crypto/secp256k1/ext.h             |  4 +
 .../secp256k1/libsecp256k1/src/group_impl.h   |  2 +-
 .../secp256k1/libsecp256k1/src/secp256k1.c    | 64 +---------------
 .../libsecp256k1/src/secp256k1_impl.h         | 74 +++++++++++++++++++
 restricted/crypto/secp256k1/panic_cb.go       |  4 +-
 restricted/crypto/secp256k1/secp256.go        | 13 +++-
 .../crypto/secp256k1/secp256_linkgeth.go      | 14 ++++
 7 files changed, 105 insertions(+), 70 deletions(-)
 create mode 100644 restricted/crypto/secp256k1/libsecp256k1/src/secp256k1_impl.h
 create mode 100644 restricted/crypto/secp256k1/secp256_linkgeth.go

diff --git a/restricted/crypto/secp256k1/ext.h b/restricted/crypto/secp256k1/ext.h
index e422fe4..3f17dc9 100644
--- a/restricted/crypto/secp256k1/ext.h
+++ b/restricted/crypto/secp256k1/ext.h
@@ -98,6 +98,9 @@ static int secp256k1_ext_reencode_pubkey(
 //  In:     point:    pointer to a 64-byte public point,
 //                    encoded as two 256bit big-endian numbers.
 //          scalar:   a 32-byte scalar with which to multiply the point
+int secp256k1_ext_scalar_mul(const secp256k1_context* ctx, unsigned char *point, const unsigned char *scalar);
+
+#ifndef PLUGETH_LINK_GETH
 int secp256k1_ext_scalar_mul(const secp256k1_context* ctx, unsigned char *point, const unsigned char *scalar) {
 	int ret = 0;
 	int overflow = 0;
@@ -128,3 +131,4 @@ int secp256k1_ext_scalar_mul(const secp256k1_context* ctx, unsigned char *point,
 	secp256k1_scalar_clear(&s);
 	return ret;
 }
+#endif
diff --git a/restricted/crypto/secp256k1/libsecp256k1/src/group_impl.h b/restricted/crypto/secp256k1/libsecp256k1/src/group_impl.h
index 7d72353..dec54e4 100644
--- a/restricted/crypto/secp256k1/libsecp256k1/src/group_impl.h
+++ b/restricted/crypto/secp256k1/libsecp256k1/src/group_impl.h
@@ -68,7 +68,7 @@ static const secp256k1_ge secp256k1_ge_const_g = SECP256K1_GE_CONST(
     0xFD17B448UL, 0xA6855419UL, 0x9C47D08FUL, 0xFB10D4B8UL
 );
 
-const int CURVE_B = 7;
+static const int CURVE_B = 7;
 #endif
 
 static void secp256k1_ge_set_gej_zinv(secp256k1_ge *r, const secp256k1_gej *a, const secp256k1_fe *zi) {
diff --git a/restricted/crypto/secp256k1/libsecp256k1/src/secp256k1.c b/restricted/crypto/secp256k1/libsecp256k1/src/secp256k1.c
index 7d637bf..794552e 100644
--- a/restricted/crypto/secp256k1/libsecp256k1/src/secp256k1.c
+++ b/restricted/crypto/secp256k1/libsecp256k1/src/secp256k1.c
@@ -4,26 +4,7 @@
  * file COPYING or http://www.opensource.org/licenses/mit-license.php.*
  **********************************************************************/
 
-#include "include/secp256k1.h"
-
-#include "util.h"
-#include "num_impl.h"
-#include "field_impl.h"
-#include "scalar_impl.h"
-#include "group_impl.h"
-#include "ecmult_impl.h"
-#include "ecmult_const_impl.h"
-#include "ecmult_gen_impl.h"
-#include "ecdsa_impl.h"
-#include "eckey_impl.h"
-#include "hash_impl.h"
-
-#define ARG_CHECK(cond) do { \
-    if (EXPECT(!(cond), 0)) { \
-        secp256k1_callback_call(&ctx->illegal_callback, #cond); \
-        return 0; \
-    } \
-} while(0)
+#include "secp256k1_impl.h"
 
 static void default_illegal_callback_fn(const char* str, void* data) {
     fprintf(stderr, "[libsecp256k1] illegal argument: %s\n", str);
@@ -46,13 +27,6 @@ static const secp256k1_callback default_error_callback = {
 };
 
 
-struct secp256k1_context_struct {
-    secp256k1_ecmult_context ecmult_ctx;
-    secp256k1_ecmult_gen_context ecmult_gen_ctx;
-    secp256k1_callback illegal_callback;
-    secp256k1_callback error_callback;
-};
-
 secp256k1_context* secp256k1_context_create(unsigned int flags) {
     secp256k1_context* ret = (secp256k1_context*)checked_malloc(&default_error_callback, sizeof(secp256k1_context));
     ret->illegal_callback = default_illegal_callback;
@@ -131,20 +105,6 @@ static int secp256k1_pubkey_load(const secp256k1_context* ctx, secp256k1_ge* ge,
     return 1;
 }
 
-static void secp256k1_pubkey_save(secp256k1_pubkey* pubkey, secp256k1_ge* ge) {
-    if (sizeof(secp256k1_ge_storage) == 64) {
-        secp256k1_ge_storage s;
-        secp256k1_ge_to_storage(&s, ge);
-        memcpy(&pubkey->data[0], &s, 64);
-    } else {
-        VERIFY_CHECK(!secp256k1_ge_is_infinity(ge));
-        secp256k1_fe_normalize_var(&ge->x);
-        secp256k1_fe_normalize_var(&ge->y);
-        secp256k1_fe_get_b32(pubkey->data, &ge->x);
-        secp256k1_fe_get_b32(pubkey->data + 32, &ge->y);
-    }
-}
-
 int secp256k1_ec_pubkey_parse(const secp256k1_context* ctx, secp256k1_pubkey* pubkey, const unsigned char *input, size_t inputlen) {
     secp256k1_ge Q;
 
@@ -197,16 +157,6 @@ static void secp256k1_ecdsa_signature_load(const secp256k1_context* ctx, secp256
     }
 }
 
-static void secp256k1_ecdsa_signature_save(secp256k1_ecdsa_signature* sig, const secp256k1_scalar* r, const secp256k1_scalar* s) {
-    if (sizeof(secp256k1_scalar) == 32) {
-        memcpy(&sig->data[0], r, 32);
-        memcpy(&sig->data[32], s, 32);
-    } else {
-        secp256k1_scalar_get_b32(&sig->data[0], r);
-        secp256k1_scalar_get_b32(&sig->data[32], s);
-    }
-}
-
 int secp256k1_ecdsa_signature_parse_der(const secp256k1_context* ctx, secp256k1_ecdsa_signature* sig, const unsigned char *input, size_t inputlen) {
     secp256k1_scalar r, s;
 
@@ -545,15 +495,3 @@ int secp256k1_ec_pubkey_combine(const secp256k1_context* ctx, secp256k1_pubkey *
     secp256k1_pubkey_save(pubnonce, &Q);
     return 1;
 }
-
-#ifdef ENABLE_MODULE_ECDH
-# include "modules/ecdh/main_impl.h"
-#endif
-
-#ifdef ENABLE_MODULE_SCHNORR
-# include "modules/schnorr/main_impl.h"
-#endif
-
-#ifdef ENABLE_MODULE_RECOVERY
-# include "modules/recovery/main_impl.h"
-#endif
diff --git a/restricted/crypto/secp256k1/libsecp256k1/src/secp256k1_impl.h b/restricted/crypto/secp256k1/libsecp256k1/src/secp256k1_impl.h
new file mode 100644
index 0000000..137fc08
--- /dev/null
+++ b/restricted/crypto/secp256k1/libsecp256k1/src/secp256k1_impl.h
@@ -0,0 +1,74 @@
+/**********************************************************************
+ * Copyright (c) 2013-2015 Pieter Wuille                              *
+ * Distributed under the MIT software license, see the accompanying   *
+ * file COPYING or http://www.opensource.org/licenses/mit-license.php.*
+ **********************************************************************/
+
+#ifndef _SECP256K1_IMPL_H_
+#define _SECP256K1_IMPL_H_
+
+#include "include/secp256k1.h"
+
+#include "util.h"
+#include "num_impl.h"
+#include "field_impl.h"
+#include "scalar_impl.h"
+#include "group_impl.h"
+#include "ecmult_impl.h"
+#include "ecmult_const_impl.h"
+#include "ecmult_gen_impl.h"
+#include "ecdsa_impl.h"
+#include "eckey_impl.h"
+#include "hash_impl.h"
+
+#define ARG_CHECK(cond) do { \
+    if (EXPECT(!(cond), 0)) { \
+        secp256k1_callback_call(&ctx->illegal_callback, #cond); \
+        return 0; \
+    } \
+} while(0)
+
+struct secp256k1_context_struct {
+    secp256k1_ecmult_context ecmult_ctx;
+    secp256k1_ecmult_gen_context ecmult_gen_ctx;
+    secp256k1_callback illegal_callback;
+    secp256k1_callback error_callback;
+};
+
+static void secp256k1_ecdsa_signature_save(secp256k1_ecdsa_signature* sig, const secp256k1_scalar* r, const secp256k1_scalar* s) {
+    if (sizeof(secp256k1_scalar) == 32) {
+        memcpy(&sig->data[0], r, 32);
+        memcpy(&sig->data[32], s, 32);
+    } else {
+        secp256k1_scalar_get_b32(&sig->data[0], r);
+        secp256k1_scalar_get_b32(&sig->data[32], s);
+    }
+}
+
+static void secp256k1_pubkey_save(secp256k1_pubkey* pubkey, secp256k1_ge* ge) {
+    if (sizeof(secp256k1_ge_storage) == 64) {
+        secp256k1_ge_storage s;
+        secp256k1_ge_to_storage(&s, ge);
+        memcpy(&pubkey->data[0], &s, 64);
+    } else {
+        VERIFY_CHECK(!secp256k1_ge_is_infinity(ge));
+        secp256k1_fe_normalize_var(&ge->x);
+        secp256k1_fe_normalize_var(&ge->y);
+        secp256k1_fe_get_b32(pubkey->data, &ge->x);
+        secp256k1_fe_get_b32(pubkey->data + 32, &ge->y);
+    }
+}
+
+#ifdef ENABLE_MODULE_ECDH
+# include "modules/ecdh/main_impl.h"
+#endif
+
+#ifdef ENABLE_MODULE_SCHNORR
+# include "modules/schnorr/main_impl.h"
+#endif
+
+#ifdef ENABLE_MODULE_RECOVERY
+# include "modules/recovery/main_impl.h"
+#endif
+
+#endif
diff --git a/restricted/crypto/secp256k1/panic_cb.go b/restricted/crypto/secp256k1/panic_cb.go
index 5da2bea..729e71a 100644
--- a/restricted/crypto/secp256k1/panic_cb.go
+++ b/restricted/crypto/secp256k1/panic_cb.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be found in
 // the LICENSE file.
 
-// +build !gofuzz
-// +build cgo
+//go:build !gofuzz && cgo && !linkgeth
+// +build !gofuzz,cgo,!linkgeth
 
 package secp256k1
 
diff --git a/restricted/crypto/secp256k1/secp256.go b/restricted/crypto/secp256k1/secp256.go
index a1bcf77..e395b7d 100644
--- a/restricted/crypto/secp256k1/secp256.go
+++ b/restricted/crypto/secp256k1/secp256.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be found in
 // the LICENSE file.
 
-// +build !gofuzz
-// +build cgo
+//go:build !gofuzz && cgo
+// +build !gofuzz,cgo
 
 // Package secp256k1 wraps the bitcoin secp256k1 C library.
 package secp256k1
@@ -26,8 +26,13 @@ package secp256k1
 #define USE_FIELD_INV_BUILTIN
 #define USE_SCALAR_INV_BUILTIN
 #define NDEBUG
-#include "./libsecp256k1/src/secp256k1.c"
-#include "./libsecp256k1/src/modules/recovery/main_impl.h"
+#ifdef PLUGETH_LINK_GETH
+#  include "./libsecp256k1/src/secp256k1_impl.h"
+#  include "./libsecp256k1/include/secp256k1_recovery.h"
+#else
+#  include "./libsecp256k1/src/secp256k1.c"
+#  include "./libsecp256k1/src/modules/recovery/main_impl.h"
+#endif
 #include "ext.h"
 
 typedef void (*callbackFunc) (const char* msg, void* data);
diff --git a/restricted/crypto/secp256k1/secp256_linkgeth.go b/restricted/crypto/secp256k1/secp256_linkgeth.go
new file mode 100644
index 0000000..2e7cf4f
--- /dev/null
+++ b/restricted/crypto/secp256k1/secp256_linkgeth.go
@@ -0,0 +1,14 @@
+// Copyright 2015 Jeffrey Wilcke, Felix Lange, Gustav Simonsson. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+//go:build !gofuzz && cgo && linkgeth
+// +build !gofuzz,cgo,linkgeth
+
+// Package secp256k1 wraps the bitcoin secp256k1 C library.
+package secp256k1
+
+/*
+#cgo CFLAGS: -DPLUGETH_LINK_GETH
+*/
+import "C"