You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
68 lines
1.8 KiB
68 lines
1.8 KiB
// Copyright (c) 2009-2010 Satoshi Nakamoto |
|
// Copyright (c) 2009-2014 The Bitcoin Core developers |
|
// Distributed under the MIT software license, see the accompanying |
|
// file COPYING or http://www.opensource.org/licenses/mit-license.php. |
|
|
|
#include "eccryptoverify.h" |
|
|
|
namespace { |
|
|
|
int CompareBigEndian(const unsigned char *c1, size_t c1len, const unsigned char *c2, size_t c2len) { |
|
while (c1len > c2len) { |
|
if (*c1) |
|
return 1; |
|
c1++; |
|
c1len--; |
|
} |
|
while (c2len > c1len) { |
|
if (*c2) |
|
return -1; |
|
c2++; |
|
c2len--; |
|
} |
|
while (c1len > 0) { |
|
if (*c1 > *c2) |
|
return 1; |
|
if (*c2 > *c1) |
|
return -1; |
|
c1++; |
|
c2++; |
|
c1len--; |
|
} |
|
return 0; |
|
} |
|
|
|
/** 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, |
|
0xBA,0xAE,0xDC,0xE6,0xAF,0x48,0xA0,0x3B, |
|
0xBF,0xD2,0x5E,0x8C,0xD0,0x36,0x41,0x40 |
|
}; |
|
|
|
/** 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, |
|
0x5D,0x57,0x6E,0x73,0x57,0xA4,0x50,0x1D, |
|
0xDF,0xE9,0x2F,0x46,0x68,0x1B,0x20,0xA0 |
|
}; |
|
|
|
const unsigned char vchZero[1] = {0}; |
|
} // anon namespace |
|
|
|
namespace eccrypto { |
|
|
|
bool Check(const unsigned char *vch) { |
|
return vch && |
|
CompareBigEndian(vch, 32, vchZero, 0) > 0 && |
|
CompareBigEndian(vch, 32, vchMaxModOrder, 32) <= 0; |
|
} |
|
|
|
bool CheckSignatureElement(const unsigned char *vch, int len, bool half) { |
|
return vch && |
|
CompareBigEndian(vch, len, vchZero, 0) > 0 && |
|
CompareBigEndian(vch, len, half ? vchMaxModHalfOrder : vchMaxModOrder, 32) <= 0; |
|
} |
|
|
|
} // namespace eccrypto
|
|
|