feat: add syscalls using Barreto-Naehrig (BN) curve construction

c/generator_utils.h

@@ -35,6 +35,10 @@
 #define GW_SYS_PAY_FEE 3501
 #define GW_SYS_LOG 3502
 #define GW_SYS_RECOVER_ACCOUNT 3503
+/* Syscall for make use the Barreto-Naehrig (BN) curve construction */
+#define GW_SYS_BN_ADD 3601
+#define GW_SYS_BN_MUL 3602
+#define GW_SYS_BN_PAIRING 3603
 
 typedef struct gw_context_t {
   /* verification context */
@@ -57,6 +61,9 @@ typedef struct gw_context_t {
   gw_store_data_fn sys_store_data;
   gw_get_block_hash_fn sys_get_block_hash;
   gw_recover_account_fn sys_recover_account;
+  gw_bn_add sys_bn_add;
+  gw_bn_mul sys_bn_mul;
+  gw_bn_pairing sys_bn_pairing;
   gw_log_fn sys_log;
   gw_pay_fee_fn sys_pay_fee;
   gw_get_registry_address_by_script_hash_fn
@@ -346,6 +353,23 @@ int sys_recover_account(struct gw_context_t *ctx, uint8_t message[32],
   return ret;
 }
 
+int sys_bn_add(const uint8_t *input, const size_t input_size, uint8_t *output) {
+  volatile uint64_t output_len = 64;
+  return syscall(GW_SYS_BN_ADD, output, &output_len, 0, input, input_size, 0);
+}
+
+int sys_bn_mul(const uint8_t *input, const size_t input_size, uint8_t *output) {
+  volatile uint64_t output_len = 64;
+  return syscall(GW_SYS_BN_MUL, output, &output_len, 0, input, input_size, 0);
+}
+
+int sys_bn_pairing(const uint8_t *input, const size_t input_size,
+                   uint8_t *output) {
+  volatile uint64_t output_size = 32;
+  return syscall(GW_SYS_BN_PAIRING, output, &output_size, 0 /* offset = 0 */,
+                 input, input_size, 0);
+}
+
 int sys_log(gw_context_t *ctx, uint32_t account_id, uint8_t service_flag,
             uint64_t data_length, const uint8_t *data) {
   if (ctx == NULL) {
@@ -415,6 +439,9 @@ int gw_context_init(gw_context_t *ctx) {
   ctx->sys_load_data = sys_load_data;
   ctx->sys_get_block_hash = sys_get_block_hash;
   ctx->sys_recover_account = sys_recover_account;
+  ctx->sys_bn_add = sys_bn_add;
+  ctx->sys_bn_mul = sys_bn_mul;
+  ctx->sys_bn_pairing = sys_bn_pairing;
   ctx->sys_pay_fee = sys_pay_fee;
   ctx->sys_log = sys_log;
   ctx->sys_get_registry_address_by_script_hash =

c/gw_def.h

@@ -105,6 +105,42 @@ int gw_verify_sudt_account(struct gw_context_t *ctx, uint32_t sudt_id);
 typedef int (*gw_create_fn)(struct gw_context_t *ctx, uint8_t *script,
                             uint64_t script_len, uint32_t *account_id);
 
+/**
+ * @param input  two curve points (x, y)
+ * @param output curve point x + y, where + is point addition on the elliptic
+ * curve
+ *
+ * Fails on invalid input
+ */
+typedef int (*gw_bn_add)(const uint8_t *input, const size_t input_size,
+                         uint8_t *output);
+
+/**
+ * @param Input  two curve points (x, y)
+ * @param output curve point s * x, where * is the scalar multiplication on the
+ * elliptic curve
+ *
+ * Fails on invalid input
+ */
+typedef int (*gw_bn_mul)(const uint8_t *input, const size_t input_size,
+                         uint8_t *output);
+
+/**
+ * @param input  Input: (a1, b1, a2, b2, ..., ak, bk) from (G_1 x G_2)^k
+ *               Note that k is the input_size divided by 192
+ * @param output curve point s * x, where * is the scalar multiplication on the
+ * elliptic curve
+ *
+ * @return Empty input is valid and results in returning one.
+ *
+ * Fails on:
+ *   1. the input_size is not a multiple of 192
+ *   2. any of the inputs are not elements of the respective group are not
+ * encoded correctly
+ */
+typedef int (*gw_bn_pairing)(const uint8_t *input, const size_t input_size,
+                             uint8_t *output);
+
 /**
  * Load value by key from current contract account
  *

c/gw_errors.h

@@ -41,6 +41,7 @@
 #define GW_ERROR_NOT_FOUND 83
 #define GW_ERROR_RECOVER 84
 #define GW_ERROR_ACCOUNT_NOT_EXISTS 85
+#define GW_UNIMPLEMENTED 86
 
 /* sUDT errors */
 #define GW_SUDT_ERROR_INSUFFICIENT_BALANCE 92

c/validator_utils.h

@@ -71,6 +71,9 @@ typedef struct gw_context_t {
   gw_recover_account_fn sys_recover_account;
   gw_log_fn sys_log;
   gw_pay_fee_fn sys_pay_fee;
+  gw_bn_add sys_bn_add;
+  gw_bn_mul sys_bn_mul;
+  gw_bn_pairing sys_bn_pairing;
   gw_get_registry_address_by_script_hash_fn
       sys_get_registry_address_by_script_hash;
   gw_get_script_hash_by_registry_address_fn
@@ -548,6 +551,22 @@ int sys_recover_account(gw_context_t *ctx, uint8_t message[32],
   return GW_FATAL_SIGNATURE_CELL_NOT_FOUND;
 }
 
+int sys_bn_add(const uint8_t *input, const size_t input_size, uint8_t *output) {
+  // TODO
+  return GW_UNIMPLEMENTED;
+}
+
+int sys_bn_mul(const uint8_t *input, const size_t input_size, uint8_t *output) {
+  // TODO
+  return GW_UNIMPLEMENTED;
+}
+
+int sys_bn_pairing(const uint8_t *input, const size_t input_size,
+                   uint8_t *output) {
+  // TODO
+  return GW_UNIMPLEMENTED;
+}
+
 int sys_create(gw_context_t *ctx, uint8_t *script, uint64_t script_len,
                uint32_t *account_id) {
   if (ctx == NULL) {
@@ -1595,6 +1614,9 @@ int gw_context_init(gw_context_t *ctx) {
   ctx->sys_load_data = sys_load_data;
   ctx->sys_get_block_hash = sys_get_block_hash;
   ctx->sys_recover_account = sys_recover_account;
+  ctx->sys_bn_add = sys_bn_add;
+  ctx->sys_bn_mul = sys_bn_mul;
+  ctx->sys_bn_pairing = sys_bn_pairing;
   ctx->sys_log = sys_log;
   ctx->sys_pay_fee = sys_pay_fee;
   ctx->sys_get_registry_address_by_script_hash =