Skip to content

Commit

Permalink
Remove unused ecwrapper code
Browse files Browse the repository at this point in the history
  • Loading branch information
sipa committed Nov 19, 2014
1 parent 2710612 commit 230f7a8
Show file tree
Hide file tree
Showing 2 changed files with 0 additions and 172 deletions.
164 changes: 0 additions & 164 deletions src/ecwrapper.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -13,43 +13,6 @@

namespace {

// 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
Expand Down Expand Up @@ -135,48 +98,6 @@ CECKey::~CECKey() {
EC_KEY_free(pkey);
}

void CECKey::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 CECKey::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 CECKey::GetPrivKeySize(bool fCompressed) {
EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
return i2d_ECPrivateKey(pkey, NULL);
}
int CECKey::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 CECKey::SetPrivKey(const unsigned char* privkey, size_t size, bool fSkipCheck) {
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 CECKey::GetPubKey(std::vector<unsigned char> &pubkey, bool fCompressed) {
EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
int nSize = i2o_ECPublicKey(pkey, NULL);
Expand All @@ -193,71 +114,13 @@ bool CECKey::SetPubKey(const unsigned char* pubkey, size_t size) {
return o2i_ECPublicKey(&pkey, &pubkey, size) != NULL;
}

bool CECKey::Sign(const uint256 &hash, std::vector<unsigned char>& vchSig) {
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 (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 CECKey::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 CECKey::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) {
std::vector<unsigned char> 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) {
std::vector<unsigned char> 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;
}

bool CECKey::Recover(const uint256 &hash, const unsigned char *p64, int rec)
{
if (rec<0 || rec>=3)
Expand All @@ -270,33 +133,6 @@ bool CECKey::Recover(const uint256 &hash, const unsigned char *p64, int rec)
return ret;
}

bool CECKey::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 CECKey::TweakPublic(const unsigned char vchTweak[32]) {
bool ret = true;
BN_CTX *ctx = BN_CTX_new();
Expand Down
8 changes: 0 additions & 8 deletions src/ecwrapper.h
Original file line number Diff line number Diff line change
Expand Up @@ -21,24 +21,16 @@ class CECKey {
CECKey();
~CECKey();

void GetSecretBytes(unsigned char vch[32]) const;
void SetSecretBytes(const unsigned char vch[32]);
int GetPrivKeySize(bool fCompressed);
int GetPrivKey(unsigned char* privkey, bool fCompressed);
bool SetPrivKey(const unsigned char* privkey, size_t size, bool fSkipCheck=false);
void GetPubKey(std::vector<unsigned char>& pubkey, bool fCompressed);
bool SetPubKey(const unsigned char* pubkey, size_t size);
bool Sign(const uint256 &hash, std::vector<unsigned char>& vchSig);
bool Verify(const uint256 &hash, const std::vector<unsigned char>& vchSig);
bool SignCompact(const uint256 &hash, unsigned char *p64, int &rec);

// 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);

static bool TweakSecret(unsigned char vchSecretOut[32], const unsigned char vchSecretIn[32], const unsigned char vchTweak[32]);
bool TweakPublic(const unsigned char vchTweak[32]);
static bool SanityCheck();
};
Expand Down

0 comments on commit 230f7a8

Please sign in to comment.