Method Load

src/crypto/sha256.cpp:780–804

}

bool CSHA256::Load(const std::vector<unsigned char>& vch) {
    if (vch.size() < 40) return false;

    uint64_t bits = ReadLE64(&vch[32]);
    size_t buf_size = (bits >> 3) % 64;

    if ((bits & 0x07) != 0 || vch.size() != 40 + buf_size) return false;

    // We want to leave the internal state of the object unchanged if false is returned.
    // So no member variables can be modified until now.

    s[0] = ReadBE32(&vch[ 0]);
    s[1] = ReadBE32(&vch[ 4]);
    s[2] = ReadBE32(&vch[ 8]);
    s[3] = ReadBE32(&vch[12]);
    s[4] = ReadBE32(&vch[16]);
    s[5] = ReadBE32(&vch[20]);
    s[6] = ReadBE32(&vch[24]);
    s[7] = ReadBE32(&vch[28]);

    bytes = bits >> 3;
    if (buf_size) memcpy(buf, &vch[40], buf_size);

    return true;
}

bool CSHA256::SafeWrite(const unsigned char* data, size_t len) {
  const uint64_t SHA256_MAX = 0x1FFFFFFFFFFFFFFF; // SHA256's maximum allowed message length in bytes.