From 254327e49a12efe2117eb229198d46af65f19b3c Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Sun, 31 Mar 2013 06:34:15 +0200
Subject: [PATCH] Begin group C interface + start/stop

---
 include/secp256k1.h |  6 ++++--
 src/group.h         | 49 +++++++++++++++++++++++++++++++++++++++++++++
 src/num.h           |  1 +
 src/num_gmp.cpp     |  7 +++++++
 src/num_openssl.cpp |  4 ++++
 src/secp256k1.cpp   | 17 ++++++++++++++--
 6 files changed, 80 insertions(+), 4 deletions(-)

diff --git a/include/secp256k1.h b/include/secp256k1.h
index 806af8b1dc7..a5b4252aebd 100644
--- a/include/secp256k1.h
+++ b/include/secp256k1.h
@@ -1,8 +1,10 @@
 #ifndef _SECP256K1_
 #define _SECP256K1_
 
-namespace secp256k1 {
-int VerifyECDSA(const unsigned char *msg, int msglen, const unsigned char *sig, int siglen, const unsigned char *pubkey, int pubkeylen);
+extern "C" {
+void secp256k1_start(void);
+void secp256k1_stop(void);
+int secp256k1_ecdsa_verify(const unsigned char *msg, int msglen, const unsigned char *sig, int siglen, const unsigned char *pubkey, int pubkeylen);
 }
 
 #endif
diff --git a/src/group.h b/src/group.h
index 0a46208ef76..34b645a5f52 100644
--- a/src/group.h
+++ b/src/group.h
@@ -6,6 +6,55 @@
 #include "num.h"
 #include "field.h"
 
+extern "C" {
+
+typedef struct {
+    secp256k1_fe_t x;
+    secp256k1_fe_t y;
+    int infinity;
+} secp256k1_ge_t;
+
+typedef struct {
+    secp256k1_fe_t x;
+    secp256k1_fe_t y;
+    secp256k1_fe_t z;
+    int infinity;
+} secp256k1_gej_t;
+
+typedef struct {
+    secp256k1_num_t order;
+    secp256k1_ge_t g;
+    secp256k1_fe_t beta;
+    secp256k1_num_t lambda, a1b2, b1, a2;
+} secp256k1_ge_consts_t;
+
+static secp256k1_ge_consts_t *secp256k1_ge_consts = NULL;
+
+void static secp256k1_ge_start(void);
+void static secp256k1_ge_stop(void);
+void static secp256k1_ge_set_infinity(secp256k1_ge_t *r);
+void static secp256k1_ge_set_xy(secp256k1_ge_t *r, const secp256k1_fe_t *x, const secp256k1_fe_t *y);
+int  static secp256k1_ge_is_infinity(const secp256k1_ge_t *a);
+void static secp256k1_ge_neg(secp256k1_ge_t *r, const secp256k1_ge_t *a);
+void static secp256k1_ge_get_hex(char *r, int *rlen, const secp256k1_ge_t *a);
+void static secp256k1_ge_set_gej(secp256k1_ge_t *r, const secp256k1_gej_t *a);
+
+void static secp256k1_gej_set_infinity(secp256k1_gej_t *r);
+void static secp256k1_gej_set_xy(secp256k1_gej_t *r, const secp256k1_fe_t *x, const secp256k1_fe_t *y);
+void static secp256k1_gej_set_xo(secp256k1_gej_t *r, const secp256k1_fe_t *x, int compressed);
+void static secp256k1_gej_set_ge(secp256k1_gej_t *r, const secp256k1_ge_t *a);
+void static secp256k1_gej_get_x(secp256k1_fe_t *r, const secp256k1_gej_t *a);
+void static secp256k1_gej_neg(secp256k1_gej_t *r, const secp256k1_gej_t *a);
+int  static secp256k1_gej_is_infinity(const secp256k1_gej_t *a);
+void static secp256k1_gej_double(secp256k1_gej_t *r, const secp256k1_gej_t *a);
+void static secp256k1_gej_add(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_gej_t *b);
+void static secp256k1_gej_add_ge(secp256k1_gej_t *r, const secp256k1_gej_t *a, const secp256k1_ge_t *b);
+void static secp256k1_gej_get_hex(char *r, int *rlen, const secp256k1_gej_t *a);
+void static secp256k1_gej_mul_lambda(secp256k1_gej_t *r, const secp256k1_gej_t *a);
+void static secp256k1_gej_split_exp(secp256k1_num_t *r1, secp256k1_num_t *r2, const secp256k1_num_t *a);
+
+}
+
 namespace secp256k1 {
 
 class GroupElemJac;
diff --git a/src/num.h b/src/num.h
index fe600db6275..2c2579af8cc 100644
--- a/src/num.h
+++ b/src/num.h
@@ -12,6 +12,7 @@
 extern "C" {
 
 void static secp256k1_num_start(void);
+void static secp256k1_num_stop(void);
 void static secp256k1_num_init(secp256k1_num_t *r);
 void static secp256k1_num_free(secp256k1_num_t *r);
 void static secp256k1_num_copy(secp256k1_num_t *r, const secp256k1_num_t *a);
diff --git a/src/num_gmp.cpp b/src/num_gmp.cpp
index e89e1b0a07e..85bb79871f4 100644
--- a/src/num_gmp.cpp
+++ b/src/num_gmp.cpp
@@ -21,6 +21,13 @@ void static secp256k1_num_start(void) {
     gmp_randinit_default(secp256k1_num_state.rng);
 }
 
+void static secp256k1_num_stop(void) {
+    if (!secp256k1_num_state.initialized)
+        return;
+    secp256k1_num_state.initialized = 0;
+    gmp_randclear(secp256k1_num_state.rng);
+}
+
 void static secp256k1_num_init(secp256k1_num_t *r) {
     mpz_init(r->bn);
 }
diff --git a/src/num_openssl.cpp b/src/num_openssl.cpp
index 50c4f6c9abf..5b88d98bacb 100644
--- a/src/num_openssl.cpp
+++ b/src/num_openssl.cpp
@@ -9,6 +9,10 @@
 void static secp256k1_num_start() {
 }
 
+void static secp256k1_num_stop() {
+}
+
+
 void static secp256k1_num_init(secp256k1_num_t *r) {
     BN_init(&r->bn);
 }
diff --git a/src/secp256k1.cpp b/src/secp256k1.cpp
index 5cdadae1a52..bbbf03ba73b 100644
--- a/src/secp256k1.cpp
+++ b/src/secp256k1.cpp
@@ -4,9 +4,22 @@
 #include "ecmult.cpp"
 #include "ecdsa.cpp"
 
+
 namespace secp256k1 {
 
-int VerifyECDSA(const unsigned char *msg, int msglen, const unsigned char *sig, int siglen, const unsigned char *pubkey, int pubkeylen) {
+extern "C" void secp256k1_start(void) {
+    secp256k1_num_start();
+    secp256k1_fe_start();
+    GetGroupConst();
+    GetECMultConsts();
+}
+
+extern "C" void secp256k1_stop(void) {
+    secp256k1_fe_stop();
+    secp256k1_num_stop();
+}
+
+extern "C" int secp256k1_ecdsa_verify(const unsigned char *msg, int msglen, const unsigned char *sig, int siglen, const unsigned char *pubkey, int pubkeylen) {
     int ret = -3;
     secp256k1_num_t m; 
     secp256k1_num_init(&m);
@@ -34,5 +47,5 @@ end:
     return ret;
 }
 
-
 }
+