md5_digest.cpp (7233B)
1 #include "md5_digest.h" 2 3 // based heavily on this implementation: 4 // http://www.fourmilab.ch/md5/ 5 6 #ifndef HIGHFIRST 7 #define byteReverse(buf, len) /* Nothing */ 8 #else 9 /* 10 * Note: this code is harmless on little-endian machines. 11 */ 12 static void byteReverse(unsigned char* buf, unsigned longs) 13 { 14 u32 t; 15 do 16 { 17 t = (u32)((unsigned)buf[3] << 8 | buf[2]) << 16 | ((unsigned)buf[1] << 8 | buf[0]); 18 *(u32*)buf = t; 19 buf += 4; 20 } while (--longs); 21 } 22 #endif 23 24 /* The four core functions - F1 is optimized somewhat */ 25 26 /* #define F1(x, y, z) (x & y | ~x & z) */ 27 #define F1(x, y, z) (z ^ (x & (y ^ z))) 28 #define F2(x, y, z) F1(z, x, y) 29 #define F3(x, y, z) (x ^ y ^ z) 30 #define F4(x, y, z) (y ^ (x | ~z)) 31 32 /* This is the central step in the MD5 algorithm. */ 33 #define MD5STEP(f, w, x, y, z, data, s) (w += f(x, y, z) + data, w = w << s | w >> (32 - s), w += x) 34 35 /* 36 * The core of the MD5 algorithm, this alters an existing MD5 hash to 37 * reflect the addition of 16 longwords of new data. MD5Update blocks 38 * the data and converts bytes into longwords for this routine. 39 */ 40 static void MD5Transform(u32 buf[4], u32 in[16]) 41 { 42 // register u32 a, b, c, d; 43 u32 a, b, c, d; 44 45 a = buf[0]; 46 b = buf[1]; 47 c = buf[2]; 48 d = buf[3]; 49 50 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7); 51 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12); 52 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17); 53 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22); 54 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7); 55 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12); 56 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17); 57 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22); 58 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7); 59 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12); 60 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17); 61 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22); 62 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7); 63 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12); 64 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17); 65 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22); 66 67 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5); 68 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9); 69 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14); 70 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); 71 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5); 72 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9); 73 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14); 74 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); 75 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5); 76 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9); 77 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14); 78 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20); 79 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5); 80 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); 81 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14); 82 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); 83 84 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4); 85 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11); 86 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16); 87 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23); 88 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4); 89 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); 90 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); 91 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23); 92 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4); 93 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11); 94 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16); 95 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23); 96 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4); 97 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11); 98 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); 99 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23); 100 101 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6); 102 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10); 103 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15); 104 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21); 105 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6); 106 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); 107 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15); 108 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21); 109 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); 110 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); 111 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15); 112 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21); 113 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6); 114 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10); 115 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); 116 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21); 117 118 buf[0] += a; 119 buf[1] += b; 120 buf[2] += c; 121 buf[3] += d; 122 } 123 124 MD5Digest::MD5Digest() 125 { 126 Reset(); 127 } 128 129 void MD5Digest::Reset() 130 { 131 this->buf[0] = 0x67452301; 132 this->buf[1] = 0xefcdab89; 133 this->buf[2] = 0x98badcfe; 134 this->buf[3] = 0x10325476; 135 136 this->bits[0] = 0; 137 this->bits[1] = 0; 138 } 139 140 std::array<u8, MD5Digest::DIGEST_SIZE> MD5Digest::HashData(std::span<const u8> data) 141 { 142 std::array<u8, DIGEST_SIZE> ret; 143 144 MD5Digest digest; 145 digest.Update(data); 146 digest.Final(ret); 147 return ret; 148 } 149 150 void MD5Digest::Update(const void* pData, u32 cbData) 151 { 152 u32 t; 153 const u8* pByteData = reinterpret_cast<const u8*>(pData); 154 155 /* Update bitcount */ 156 157 t = this->bits[0]; 158 if ((this->bits[0] = t + ((u32)cbData << 3)) < t) 159 this->bits[1]++; /* Carry from low to high */ 160 this->bits[1] += cbData >> 29; 161 162 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */ 163 164 /* Handle any leading odd-sized chunks */ 165 166 if (t) 167 { 168 u8* p = (u8*)this->in + t; 169 170 t = 64 - t; 171 if (cbData < t) 172 { 173 std::memcpy(p, pByteData, cbData); 174 return; 175 } 176 std::memcpy(p, pByteData, t); 177 byteReverse(this->in, 16); 178 MD5Transform(this->buf, (u32*)this->in); 179 pByteData += t; 180 cbData -= t; 181 } 182 /* Process data in 64-byte chunks */ 183 184 while (cbData >= 64) 185 { 186 std::memcpy(this->in, pByteData, 64); 187 byteReverse(this->in, 16); 188 MD5Transform(this->buf, (u32*)this->in); 189 pByteData += 64; 190 cbData -= 64; 191 } 192 193 /* Handle any remaining bytes of data. */ 194 195 std::memcpy(this->in, pByteData, cbData); 196 } 197 198 void MD5Digest::Update(std::span<const u8> data) 199 { 200 if (!data.empty()) 201 Update(data.data(), static_cast<u32>(data.size_bytes())); 202 } 203 204 void MD5Digest::Final(std::span<u8, DIGEST_SIZE> digest) 205 { 206 u32 count; 207 u8* p; 208 209 /* Compute number of bytes mod 64 */ 210 count = (this->bits[0] >> 3) & 0x3F; 211 212 /* Set the first char of padding to 0x80. This is safe since there is 213 always at least one byte free */ 214 p = this->in + count; 215 *p++ = 0x80; 216 217 /* Bytes of padding needed to make 64 bytes */ 218 count = 64 - 1 - count; 219 220 /* Pad out to 56 mod 64 */ 221 if (count < 8) 222 { 223 /* Two lots of padding: Pad the first block to 64 bytes */ 224 std::memset(p, 0, count); 225 byteReverse(this->in, 16); 226 MD5Transform(this->buf, (u32*)this->in); 227 228 /* Now fill the next block with 56 bytes */ 229 std::memset(this->in, 0, 56); 230 } 231 else 232 { 233 /* Pad block to 56 bytes */ 234 std::memset(p, 0, count - 8); 235 } 236 byteReverse(this->in, 14); 237 238 /* Append length in bits and transform */ 239 ((u32*)this->in)[14] = this->bits[0]; 240 ((u32*)this->in)[15] = this->bits[1]; 241 242 MD5Transform(this->buf, (u32*)this->in); 243 byteReverse((unsigned char*)this->buf, 4); 244 std::memcpy(digest.data(), this->buf, 16); 245 }