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-rw-r--r--src/key.cpp372
1 files changed, 26 insertions, 346 deletions
diff --git a/src/key.cpp b/src/key.cpp
index 079e2c6540..c466e84f26 100644
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -1,5 +1,5 @@
// Copyright (c) 2009-2014 The Bitcoin developers
-// Distributed under the MIT/X11 software license, see the accompanying
+// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include "key.h"
@@ -10,12 +10,10 @@
#ifdef USE_SECP256K1
#include <secp256k1.h>
#else
-#include <openssl/bn.h>
-#include <openssl/ecdsa.h>
-#include <openssl/obj_mac.h>
+#include "ecwrapper.h"
#endif
-// anonymous namespace with local implementation code (OpenSSL interaction)
+//! anonymous namespace
namespace {
#ifdef USE_SECP256K1
@@ -31,326 +29,6 @@ public:
};
static CSecp256k1Init instance_of_csecp256k1;
-#else
-
-// Generate a private key from just the secret parameter
-int EC_KEY_regenerate_key(EC_KEY *eckey, BIGNUM *priv_key)
-{
- int ok = 0;
- BN_CTX *ctx = NULL;
- EC_POINT *pub_key = NULL;
-
- if (!eckey) return 0;
-
- const EC_GROUP *group = EC_KEY_get0_group(eckey);
-
- if ((ctx = BN_CTX_new()) == NULL)
- goto err;
-
- pub_key = EC_POINT_new(group);
-
- if (pub_key == NULL)
- goto err;
-
- if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, ctx))
- goto err;
-
- EC_KEY_set_private_key(eckey,priv_key);
- EC_KEY_set_public_key(eckey,pub_key);
-
- ok = 1;
-
-err:
-
- if (pub_key)
- EC_POINT_free(pub_key);
- if (ctx != NULL)
- BN_CTX_free(ctx);
-
- return(ok);
-}
-
-// Perform ECDSA key recovery (see SEC1 4.1.6) for curves over (mod p)-fields
-// recid selects which key is recovered
-// if check is non-zero, additional checks are performed
-int ECDSA_SIG_recover_key_GFp(EC_KEY *eckey, ECDSA_SIG *ecsig, const unsigned char *msg, int msglen, int recid, int check)
-{
- if (!eckey) return 0;
-
- int ret = 0;
- BN_CTX *ctx = NULL;
-
- BIGNUM *x = NULL;
- BIGNUM *e = NULL;
- BIGNUM *order = NULL;
- BIGNUM *sor = NULL;
- BIGNUM *eor = NULL;
- BIGNUM *field = NULL;
- EC_POINT *R = NULL;
- EC_POINT *O = NULL;
- EC_POINT *Q = NULL;
- BIGNUM *rr = NULL;
- BIGNUM *zero = NULL;
- int n = 0;
- int i = recid / 2;
-
- const EC_GROUP *group = EC_KEY_get0_group(eckey);
- if ((ctx = BN_CTX_new()) == NULL) { ret = -1; goto err; }
- BN_CTX_start(ctx);
- order = BN_CTX_get(ctx);
- if (!EC_GROUP_get_order(group, order, ctx)) { ret = -2; goto err; }
- x = BN_CTX_get(ctx);
- if (!BN_copy(x, order)) { ret=-1; goto err; }
- if (!BN_mul_word(x, i)) { ret=-1; goto err; }
- if (!BN_add(x, x, ecsig->r)) { ret=-1; goto err; }
- field = BN_CTX_get(ctx);
- if (!EC_GROUP_get_curve_GFp(group, field, NULL, NULL, ctx)) { ret=-2; goto err; }
- if (BN_cmp(x, field) >= 0) { ret=0; goto err; }
- if ((R = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
- if (!EC_POINT_set_compressed_coordinates_GFp(group, R, x, recid % 2, ctx)) { ret=0; goto err; }
- if (check)
- {
- if ((O = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
- if (!EC_POINT_mul(group, O, NULL, R, order, ctx)) { ret=-2; goto err; }
- if (!EC_POINT_is_at_infinity(group, O)) { ret = 0; goto err; }
- }
- if ((Q = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
- n = EC_GROUP_get_degree(group);
- e = BN_CTX_get(ctx);
- if (!BN_bin2bn(msg, msglen, e)) { ret=-1; goto err; }
- if (8*msglen > n) BN_rshift(e, e, 8-(n & 7));
- zero = BN_CTX_get(ctx);
- if (!BN_zero(zero)) { ret=-1; goto err; }
- if (!BN_mod_sub(e, zero, e, order, ctx)) { ret=-1; goto err; }
- rr = BN_CTX_get(ctx);
- if (!BN_mod_inverse(rr, ecsig->r, order, ctx)) { ret=-1; goto err; }
- sor = BN_CTX_get(ctx);
- if (!BN_mod_mul(sor, ecsig->s, rr, order, ctx)) { ret=-1; goto err; }
- eor = BN_CTX_get(ctx);
- if (!BN_mod_mul(eor, e, rr, order, ctx)) { ret=-1; goto err; }
- if (!EC_POINT_mul(group, Q, eor, R, sor, ctx)) { ret=-2; goto err; }
- if (!EC_KEY_set_public_key(eckey, Q)) { ret=-2; goto err; }
-
- ret = 1;
-
-err:
- if (ctx) {
- BN_CTX_end(ctx);
- BN_CTX_free(ctx);
- }
- if (R != NULL) EC_POINT_free(R);
- if (O != NULL) EC_POINT_free(O);
- if (Q != NULL) EC_POINT_free(Q);
- return ret;
-}
-
-// RAII Wrapper around OpenSSL's EC_KEY
-class CECKey {
-private:
- EC_KEY *pkey;
-
-public:
- CECKey() {
- pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
- assert(pkey != NULL);
- }
-
- ~CECKey() {
- EC_KEY_free(pkey);
- }
-
- void GetSecretBytes(unsigned char vch[32]) const {
- const BIGNUM *bn = EC_KEY_get0_private_key(pkey);
- assert(bn);
- int nBytes = BN_num_bytes(bn);
- int n=BN_bn2bin(bn,&vch[32 - nBytes]);
- assert(n == nBytes);
- memset(vch, 0, 32 - nBytes);
- }
-
- void SetSecretBytes(const unsigned char vch[32]) {
- bool ret;
- BIGNUM bn;
- BN_init(&bn);
- ret = BN_bin2bn(vch, 32, &bn) != NULL;
- assert(ret);
- ret = EC_KEY_regenerate_key(pkey, &bn) != 0;
- assert(ret);
- BN_clear_free(&bn);
- }
-
- int GetPrivKeySize(bool fCompressed) {
- EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
- return i2d_ECPrivateKey(pkey, NULL);
- }
- int GetPrivKey(unsigned char* privkey, bool fCompressed) {
- EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
- return i2d_ECPrivateKey(pkey, &privkey);
- }
-
- bool SetPrivKey(const unsigned char* privkey, size_t size, bool fSkipCheck=false) {
- if (d2i_ECPrivateKey(&pkey, &privkey, size)) {
- if(fSkipCheck)
- return true;
-
- // d2i_ECPrivateKey returns true if parsing succeeds.
- // This doesn't necessarily mean the key is valid.
- if (EC_KEY_check_key(pkey))
- return true;
- }
- return false;
- }
-
- void GetPubKey(CPubKey &pubkey, bool fCompressed) {
- EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
- int nSize = i2o_ECPublicKey(pkey, NULL);
- assert(nSize);
- assert(nSize <= 65);
- unsigned char c[65];
- unsigned char *pbegin = c;
- int nSize2 = i2o_ECPublicKey(pkey, &pbegin);
- assert(nSize == nSize2);
- pubkey.Set(&c[0], &c[nSize]);
- }
-
- bool SetPubKey(const CPubKey &pubkey) {
- const unsigned char* pbegin = pubkey.begin();
- return o2i_ECPublicKey(&pkey, &pbegin, pubkey.size()) != NULL;
- }
-
- bool Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, bool lowS) {
- vchSig.clear();
- ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
- if (sig == NULL)
- return false;
- BN_CTX *ctx = BN_CTX_new();
- BN_CTX_start(ctx);
- const EC_GROUP *group = EC_KEY_get0_group(pkey);
- BIGNUM *order = BN_CTX_get(ctx);
- BIGNUM *halforder = BN_CTX_get(ctx);
- EC_GROUP_get_order(group, order, ctx);
- BN_rshift1(halforder, order);
- if (lowS && BN_cmp(sig->s, halforder) > 0) {
- // enforce low S values, by negating the value (modulo the order) if above order/2.
- BN_sub(sig->s, order, sig->s);
- }
- BN_CTX_end(ctx);
- BN_CTX_free(ctx);
- unsigned int nSize = ECDSA_size(pkey);
- vchSig.resize(nSize); // Make sure it is big enough
- unsigned char *pos = &vchSig[0];
- nSize = i2d_ECDSA_SIG(sig, &pos);
- ECDSA_SIG_free(sig);
- vchSig.resize(nSize); // Shrink to fit actual size
- return true;
- }
-
- bool Verify(const uint256 &hash, const std::vector<unsigned char>& vchSig) {
- // -1 = error, 0 = bad sig, 1 = good
- if (ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], vchSig.size(), pkey) != 1)
- return false;
- return true;
- }
-
- bool SignCompact(const uint256 &hash, unsigned char *p64, int &rec) {
- bool fOk = false;
- ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
- if (sig==NULL)
- return false;
- memset(p64, 0, 64);
- int nBitsR = BN_num_bits(sig->r);
- int nBitsS = BN_num_bits(sig->s);
- if (nBitsR <= 256 && nBitsS <= 256) {
- CPubKey pubkey;
- GetPubKey(pubkey, true);
- for (int i=0; i<4; i++) {
- CECKey keyRec;
- if (ECDSA_SIG_recover_key_GFp(keyRec.pkey, sig, (unsigned char*)&hash, sizeof(hash), i, 1) == 1) {
- CPubKey pubkeyRec;
- keyRec.GetPubKey(pubkeyRec, true);
- if (pubkeyRec == pubkey) {
- rec = i;
- fOk = true;
- break;
- }
- }
- }
- assert(fOk);
- BN_bn2bin(sig->r,&p64[32-(nBitsR+7)/8]);
- BN_bn2bin(sig->s,&p64[64-(nBitsS+7)/8]);
- }
- ECDSA_SIG_free(sig);
- return fOk;
- }
-
- // reconstruct public key from a compact signature
- // This is only slightly more CPU intensive than just verifying it.
- // If this function succeeds, the recovered public key is guaranteed to be valid
- // (the signature is a valid signature of the given data for that key)
- bool Recover(const uint256 &hash, const unsigned char *p64, int rec)
- {
- if (rec<0 || rec>=3)
- return false;
- ECDSA_SIG *sig = ECDSA_SIG_new();
- BN_bin2bn(&p64[0], 32, sig->r);
- BN_bin2bn(&p64[32], 32, sig->s);
- bool ret = ECDSA_SIG_recover_key_GFp(pkey, sig, (unsigned char*)&hash, sizeof(hash), rec, 0) == 1;
- ECDSA_SIG_free(sig);
- return ret;
- }
-
- static bool TweakSecret(unsigned char vchSecretOut[32], const unsigned char vchSecretIn[32], const unsigned char vchTweak[32])
- {
- bool ret = true;
- BN_CTX *ctx = BN_CTX_new();
- BN_CTX_start(ctx);
- BIGNUM *bnSecret = BN_CTX_get(ctx);
- BIGNUM *bnTweak = BN_CTX_get(ctx);
- BIGNUM *bnOrder = BN_CTX_get(ctx);
- EC_GROUP *group = EC_GROUP_new_by_curve_name(NID_secp256k1);
- EC_GROUP_get_order(group, bnOrder, ctx); // what a grossly inefficient way to get the (constant) group order...
- BN_bin2bn(vchTweak, 32, bnTweak);
- if (BN_cmp(bnTweak, bnOrder) >= 0)
- ret = false; // extremely unlikely
- BN_bin2bn(vchSecretIn, 32, bnSecret);
- BN_add(bnSecret, bnSecret, bnTweak);
- BN_nnmod(bnSecret, bnSecret, bnOrder, ctx);
- if (BN_is_zero(bnSecret))
- ret = false; // ridiculously unlikely
- int nBits = BN_num_bits(bnSecret);
- memset(vchSecretOut, 0, 32);
- BN_bn2bin(bnSecret, &vchSecretOut[32-(nBits+7)/8]);
- EC_GROUP_free(group);
- BN_CTX_end(ctx);
- BN_CTX_free(ctx);
- return ret;
- }
-
- bool TweakPublic(const unsigned char vchTweak[32]) {
- bool ret = true;
- BN_CTX *ctx = BN_CTX_new();
- BN_CTX_start(ctx);
- BIGNUM *bnTweak = BN_CTX_get(ctx);
- BIGNUM *bnOrder = BN_CTX_get(ctx);
- BIGNUM *bnOne = BN_CTX_get(ctx);
- const EC_GROUP *group = EC_KEY_get0_group(pkey);
- EC_GROUP_get_order(group, bnOrder, ctx); // what a grossly inefficient way to get the (constant) group order...
- BN_bin2bn(vchTweak, 32, bnTweak);
- if (BN_cmp(bnTweak, bnOrder) >= 0)
- ret = false; // extremely unlikely
- EC_POINT *point = EC_POINT_dup(EC_KEY_get0_public_key(pkey), group);
- BN_one(bnOne);
- EC_POINT_mul(group, point, bnTweak, point, bnOne, ctx);
- if (EC_POINT_is_at_infinity(group, point))
- ret = false; // ridiculously unlikely
- EC_KEY_set_public_key(pkey, point);
- EC_POINT_free(point);
- BN_CTX_end(ctx);
- BN_CTX_free(ctx);
- return ret;
- }
-};
-
#endif
int CompareBigEndian(const unsigned char *c1, size_t c1len, const unsigned char *c2, size_t c2len) {
@@ -378,7 +56,7 @@ int CompareBigEndian(const unsigned char *c1, size_t c1len, const unsigned char
return 0;
}
-// Order of secp256k1's generator minus 1.
+/** Order of secp256k1's generator minus 1. */
const unsigned char vchMaxModOrder[32] = {
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFE,
@@ -386,7 +64,7 @@ const unsigned char vchMaxModOrder[32] = {
0xBF,0xD2,0x5E,0x8C,0xD0,0x36,0x41,0x40
};
-// Half of the order of secp256k1's generator minus 1.
+/** Half of the order of secp256k1's generator minus 1. */
const unsigned char vchMaxModHalfOrder[32] = {
0x7F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
@@ -455,19 +133,21 @@ CPrivKey CKey::GetPrivKey() const {
CPubKey CKey::GetPubKey() const {
assert(fValid);
- CPubKey pubkey;
+ CPubKey result;
#ifdef USE_SECP256K1
int clen = 65;
- int ret = secp256k1_ecdsa_pubkey_create((unsigned char*)pubkey.begin(), &clen, begin(), fCompressed);
+ int ret = secp256k1_ecdsa_pubkey_create((unsigned char*)result.begin(), &clen, begin(), fCompressed);
+ assert((int)result.size() == clen);
assert(ret);
- assert(pubkey.IsValid());
- assert((int)pubkey.size() == clen);
#else
+ std::vector<unsigned char> pubkey;
CECKey key;
key.SetSecretBytes(vch);
key.GetPubKey(pubkey, fCompressed);
+ result.Set(pubkey.begin(), pubkey.end());
#endif
- return pubkey;
+ assert(result.IsValid());
+ return result;
}
bool CKey::Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, bool lowS) const {
@@ -544,7 +224,7 @@ bool CPubKey::Verify(const uint256 &hash, const std::vector<unsigned char>& vchS
return false;
#else
CECKey key;
- if (!key.SetPubKey(*this))
+ if (!key.SetPubKey(begin(), size()))
return false;
if (!key.Verify(hash, vchSig))
return false;
@@ -566,7 +246,9 @@ bool CPubKey::RecoverCompact(const uint256 &hash, const std::vector<unsigned cha
CECKey key;
if (!key.Recover(hash, &vchSig[1], recid))
return false;
- key.GetPubKey(*this, fComp);
+ std::vector<unsigned char> pubkey;
+ key.GetPubKey(pubkey, fComp);
+ Set(pubkey.begin(), pubkey.end());
#endif
return true;
}
@@ -579,7 +261,7 @@ bool CPubKey::IsFullyValid() const {
return false;
#else
CECKey key;
- if (!key.SetPubKey(*this))
+ if (!key.SetPubKey(begin(), size()))
return false;
#endif
return true;
@@ -595,9 +277,11 @@ bool CPubKey::Decompress() {
assert(clen == (int)size());
#else
CECKey key;
- if (!key.SetPubKey(*this))
+ if (!key.SetPubKey(begin(), size()))
return false;
- key.GetPubKey(*this, false);
+ std::vector<unsigned char> pubkey;
+ key.GetPubKey(pubkey, false);
+ Set(pubkey.begin(), pubkey.end());
#endif
return true;
}
@@ -652,9 +336,11 @@ bool CPubKey::Derive(CPubKey& pubkeyChild, unsigned char ccChild[32], unsigned i
bool ret = secp256k1_ecdsa_pubkey_tweak_add((unsigned char*)pubkeyChild.begin(), pubkeyChild.size(), out);
#else
CECKey key;
- bool ret = key.SetPubKey(*this);
+ bool ret = key.SetPubKey(begin(), size());
ret &= key.TweakPublic(out);
- key.GetPubKey(pubkeyChild, true);
+ std::vector<unsigned char> pubkey;
+ key.GetPubKey(pubkey, true);
+ pubkeyChild.Set(pubkey.begin(), pubkey.end());
#endif
return ret;
}
@@ -739,12 +425,6 @@ bool ECC_InitSanityCheck() {
#ifdef USE_SECP256K1
return true;
#else
- EC_KEY *pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
- if(pkey == NULL)
- return false;
- EC_KEY_free(pkey);
-
- // TODO Is there more EC functionality that could be missing?
- return true;
+ return CECKey::SanityCheck();
#endif
}
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-06 05:17:25 +0000