Update key.cpp to new secp256k1 API

1 files changed, 131 insertions, 24 deletions

diff --git a/src/key.cpp b/src/key.cpp
index b772dff333..a24fa8a4ba 100644
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -7,17 +7,120 @@
 #include "arith_uint256.h"
 #include "crypto/common.h"
 #include "crypto/hmac_sha512.h"
-#include "eccryptoverify.h"
 #include "pubkey.h"
 #include "random.h"
 
 #include <secp256k1.h>
-#include "ecwrapper.h"
+#include <secp256k1_recovery.h>
 
-static secp256k1_context_t* secp256k1_context = NULL;
+static secp256k1_context* secp256k1_context_sign = NULL;
+
+/** These functions are taken from the libsecp256k1 distribution and are very ugly. */
+static int ec_privkey_import_der(const secp256k1_context* ctx, unsigned char *out32, const unsigned char *privkey, size_t privkeylen) {
+    const unsigned char *end = privkey + privkeylen;
+    int lenb = 0;
+    int len = 0;
+    memset(out32, 0, 32);
+    /* sequence header */
+    if (end < privkey+1 || *privkey != 0x30) {
+        return 0;
+    }
+    privkey++;
+    /* sequence length constructor */
+    if (end < privkey+1 || !(*privkey & 0x80)) {
+        return 0;
+    }
+    lenb = *privkey & ~0x80; privkey++;
+    if (lenb < 1 || lenb > 2) {
+        return 0;
+    }
+    if (end < privkey+lenb) {
+        return 0;
+    }
+    /* sequence length */
+    len = privkey[lenb-1] | (lenb > 1 ? privkey[lenb-2] << 8 : 0);
+    privkey += lenb;
+    if (end < privkey+len) {
+        return 0;
+    }
+    /* sequence element 0: version number (=1) */
+    if (end < privkey+3 || privkey[0] != 0x02 || privkey[1] != 0x01 || privkey[2] != 0x01) {
+        return 0;
+    }
+    privkey += 3;
+    /* sequence element 1: octet string, up to 32 bytes */
+    if (end < privkey+2 || privkey[0] != 0x04 || privkey[1] > 0x20 || end < privkey+2+privkey[1]) {
+        return 0;
+    }
+    memcpy(out32 + 32 - privkey[1], privkey + 2, privkey[1]);
+    if (!secp256k1_ec_seckey_verify(ctx, out32)) {
+        memset(out32, 0, 32);
+        return 0;
+    }
+    return 1;
+}
+
+static int ec_privkey_export_der(const secp256k1_context *ctx, unsigned char *privkey, size_t *privkeylen, const unsigned char *key32, int compressed) {
+    secp256k1_pubkey pubkey;
+    size_t pubkeylen = 0;
+    if (!secp256k1_ec_pubkey_create(ctx, &pubkey, key32)) {
+        *privkeylen = 0;
+        return 0;
+    }
+    if (compressed) {
+        static const unsigned char begin[] = {
+            0x30,0x81,0xD3,0x02,0x01,0x01,0x04,0x20
+        };
+        static const unsigned char middle[] = {
+            0xA0,0x81,0x85,0x30,0x81,0x82,0x02,0x01,0x01,0x30,0x2C,0x06,0x07,0x2A,0x86,0x48,
+            0xCE,0x3D,0x01,0x01,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+            0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+            0xFF,0xFF,0xFE,0xFF,0xFF,0xFC,0x2F,0x30,0x06,0x04,0x01,0x00,0x04,0x01,0x07,0x04,
+            0x21,0x02,0x79,0xBE,0x66,0x7E,0xF9,0xDC,0xBB,0xAC,0x55,0xA0,0x62,0x95,0xCE,0x87,
+            0x0B,0x07,0x02,0x9B,0xFC,0xDB,0x2D,0xCE,0x28,0xD9,0x59,0xF2,0x81,0x5B,0x16,0xF8,
+            0x17,0x98,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+            0xFF,0xFF,0xFF,0xFF,0xFE,0xBA,0xAE,0xDC,0xE6,0xAF,0x48,0xA0,0x3B,0xBF,0xD2,0x5E,
+            0x8C,0xD0,0x36,0x41,0x41,0x02,0x01,0x01,0xA1,0x24,0x03,0x22,0x00
+        };
+        unsigned char *ptr = privkey;
+        memcpy(ptr, begin, sizeof(begin)); ptr += sizeof(begin);
+        memcpy(ptr, key32, 32); ptr += 32;
+        memcpy(ptr, middle, sizeof(middle)); ptr += sizeof(middle);
+        pubkeylen = 33;
+        secp256k1_ec_pubkey_serialize(ctx, ptr, &pubkeylen, &pubkey, SECP256K1_EC_COMPRESSED);
+        ptr += pubkeylen;
+        *privkeylen = ptr - privkey;
+    } else {
+        static const unsigned char begin[] = {
+            0x30,0x82,0x01,0x13,0x02,0x01,0x01,0x04,0x20
+        };
+        static const unsigned char middle[] = {
+            0xA0,0x81,0xA5,0x30,0x81,0xA2,0x02,0x01,0x01,0x30,0x2C,0x06,0x07,0x2A,0x86,0x48,
+            0xCE,0x3D,0x01,0x01,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+            0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+            0xFF,0xFF,0xFE,0xFF,0xFF,0xFC,0x2F,0x30,0x06,0x04,0x01,0x00,0x04,0x01,0x07,0x04,
+            0x41,0x04,0x79,0xBE,0x66,0x7E,0xF9,0xDC,0xBB,0xAC,0x55,0xA0,0x62,0x95,0xCE,0x87,
+            0x0B,0x07,0x02,0x9B,0xFC,0xDB,0x2D,0xCE,0x28,0xD9,0x59,0xF2,0x81,0x5B,0x16,0xF8,
+            0x17,0x98,0x48,0x3A,0xDA,0x77,0x26,0xA3,0xC4,0x65,0x5D,0xA4,0xFB,0xFC,0x0E,0x11,
+            0x08,0xA8,0xFD,0x17,0xB4,0x48,0xA6,0x85,0x54,0x19,0x9C,0x47,0xD0,0x8F,0xFB,0x10,
+            0xD4,0xB8,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+            0xFF,0xFF,0xFF,0xFF,0xFE,0xBA,0xAE,0xDC,0xE6,0xAF,0x48,0xA0,0x3B,0xBF,0xD2,0x5E,
+            0x8C,0xD0,0x36,0x41,0x41,0x02,0x01,0x01,0xA1,0x44,0x03,0x42,0x00
+        };
+        unsigned char *ptr = privkey;
+        memcpy(ptr, begin, sizeof(begin)); ptr += sizeof(begin);
+        memcpy(ptr, key32, 32); ptr += 32;
+        memcpy(ptr, middle, sizeof(middle)); ptr += sizeof(middle);
+        pubkeylen = 65;
+        secp256k1_ec_pubkey_serialize(ctx, ptr, &pubkeylen, &pubkey, SECP256K1_EC_UNCOMPRESSED);
+        ptr += pubkeylen;
+        *privkeylen = ptr - privkey;
+    }
+    return 1;
+}
 
 bool CKey::Check(const unsigned char *vch) {
-    return eccrypto::Check(vch);
+    return secp256k1_ec_seckey_verify(secp256k1_context_sign, vch);
 }
 
 void CKey::MakeNewKey(bool fCompressedIn) {
@@ -30,7 +133,7 @@ void CKey::MakeNewKey(bool fCompressedIn) {
 }
 
 bool CKey::SetPrivKey(const CPrivKey &privkey, bool fCompressedIn) {
-    if (!secp256k1_ec_privkey_import(secp256k1_context, (unsigned char*)begin(), &privkey[0], privkey.size()))
+    if (!ec_privkey_import_der(secp256k1_context_sign, (unsigned char*)begin(), &privkey[0], privkey.size()))
         return false;
     fCompressed = fCompressedIn;
     fValid = true;
@@ -40,10 +143,11 @@ bool CKey::SetPrivKey(const CPrivKey &privkey, bool fCompressedIn) {
 CPrivKey CKey::GetPrivKey() const {
     assert(fValid);
     CPrivKey privkey;
-    int privkeylen, ret;
+    int ret;
+    size_t privkeylen;
     privkey.resize(279);
     privkeylen = 279;
-    ret = secp256k1_ec_privkey_export(secp256k1_context, begin(), (unsigned char*)&privkey[0], &privkeylen, fCompressed);
+    ret = ec_privkey_export_der(secp256k1_context_sign, (unsigned char*)&privkey[0], &privkeylen, begin(), fCompressed ? SECP256K1_EC_COMPRESSED : SECP256K1_EC_UNCOMPRESSED);
     assert(ret);
     privkey.resize(privkeylen);
     return privkey;
@@ -51,11 +155,13 @@ CPrivKey CKey::GetPrivKey() const {
 
 CPubKey CKey::GetPubKey() const {
     assert(fValid);
+    secp256k1_pubkey pubkey;
+    size_t clen = 65;
     CPubKey result;
-    int clen = 65;
-    int ret = secp256k1_ec_pubkey_create(secp256k1_context, (unsigned char*)result.begin(), &clen, begin(), fCompressed);
-    assert((int)result.size() == clen);
+    int ret = secp256k1_ec_pubkey_create(secp256k1_context_sign, &pubkey, begin());
     assert(ret);
+    secp256k1_ec_pubkey_serialize(secp256k1_context_sign, (unsigned char*)result.begin(), &clen, &pubkey, fCompressed ? SECP256K1_EC_COMPRESSED : SECP256K1_EC_UNCOMPRESSED);
+    assert(result.size() == clen);
     assert(result.IsValid());
     return result;
 }
@@ -64,11 +170,13 @@ bool CKey::Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, uint32_
     if (!fValid)
         return false;
     vchSig.resize(72);
-    int nSigLen = 72;
+    size_t nSigLen = 72;
     unsigned char extra_entropy[32] = {0};
     WriteLE32(extra_entropy, test_case);
-    int ret = secp256k1_ecdsa_sign(secp256k1_context, hash.begin(), (unsigned char*)&vchSig[0], &nSigLen, begin(), secp256k1_nonce_function_rfc6979, test_case ? extra_entropy : NULL);
+    secp256k1_ecdsa_signature sig;
+    int ret = secp256k1_ecdsa_sign(secp256k1_context_sign, &sig, hash.begin(), begin(), secp256k1_nonce_function_rfc6979, test_case ? extra_entropy : NULL);
     assert(ret);
+    secp256k1_ecdsa_signature_serialize_der(secp256k1_context_sign, (unsigned char*)&vchSig[0], &nSigLen, &sig);
     vchSig.resize(nSigLen);
     return true;
 }
@@ -92,7 +200,10 @@ bool CKey::SignCompact(const uint256 &hash, std::vector<unsigned char>& vchSig)
         return false;
     vchSig.resize(65);
     int rec = -1;
-    int ret = secp256k1_ecdsa_sign_compact(secp256k1_context, hash.begin(), &vchSig[1], begin(), secp256k1_nonce_function_rfc6979, NULL, &rec);
+    secp256k1_ecdsa_recoverable_signature sig;
+    int ret = secp256k1_ecdsa_sign_recoverable(secp256k1_context_sign, &sig, hash.begin(), begin(), secp256k1_nonce_function_rfc6979, NULL);
+    assert(ret);
+    secp256k1_ecdsa_recoverable_signature_serialize_compact(secp256k1_context_sign, (unsigned char*)&vchSig[1], &rec, &sig);
     assert(ret);
     assert(rec != -1);
     vchSig[0] = 27 + rec + (fCompressed ? 4 : 0);
@@ -100,7 +211,7 @@ bool CKey::SignCompact(const uint256 &hash, std::vector<unsigned char>& vchSig)
 }
 
 bool CKey::Load(CPrivKey &privkey, CPubKey &vchPubKey, bool fSkipCheck=false) {
-    if (!secp256k1_ec_privkey_import(secp256k1_context, (unsigned char*)begin(), &privkey[0], privkey.size()))
+    if (!ec_privkey_import_der(secp256k1_context_sign, (unsigned char*)begin(), &privkey[0], privkey.size()))
         return false;
     fCompressed = vchPubKey.IsCompressed();
     fValid = true;
@@ -126,7 +237,7 @@ bool CKey::Derive(CKey& keyChild, ChainCode &ccChild, unsigned int nChild, const
     }
     memcpy(ccChild.begin(), out+32, 32);
     memcpy((unsigned char*)keyChild.begin(), begin(), 32);
-    bool ret = secp256k1_ec_privkey_tweak_add(secp256k1_context, (unsigned char*)keyChild.begin(), out);
+    bool ret = secp256k1_ec_privkey_tweak_add(secp256k1_context_sign, (unsigned char*)keyChild.begin(), out);
     UnlockObject(out);
     keyChild.fCompressed = true;
     keyChild.fValid = ret;
@@ -184,20 +295,16 @@ void CExtKey::Decode(const unsigned char code[74]) {
 }
 
 bool ECC_InitSanityCheck() {
-    if (!CECKey::SanityCheck()) {
-        return false;
-    }
     CKey key;
     key.MakeNewKey(true);
     CPubKey pubkey = key.GetPubKey();
     return key.VerifyPubKey(pubkey);
 }
 
-
 void ECC_Start() {
-    assert(secp256k1_context == NULL);
+    assert(secp256k1_context_sign == NULL);
 
-    secp256k1_context_t *ctx = secp256k1_context_create(SECP256K1_CONTEXT_SIGN);
+    secp256k1_context *ctx = secp256k1_context_create(SECP256K1_CONTEXT_SIGN);
     assert(ctx != NULL);
 
     {
@@ -210,12 +317,12 @@ void ECC_Start() {
         UnlockObject(seed);
     }
 
-    secp256k1_context = ctx;
+    secp256k1_context_sign = ctx;
 }
 
 void ECC_Stop() {
-    secp256k1_context_t *ctx = secp256k1_context;
-    secp256k1_context = NULL;
+    secp256k1_context *ctx = secp256k1_context_sign;
+    secp256k1_context_sign = NULL;
 
     if (ctx) {
         secp256k1_context_destroy(ctx);