1 #include "xmpmeta/md5.h" 2 3 #include <string.h> // for memcpy(). 4 5 #include <vector> 6 7 #include "base/integral_types.h" 8 #include "strings/escaping.h" 9 10 namespace dynamic_depth { 11 namespace xmpmeta { 12 namespace { 13 14 const int kMd5DigestSize = 16; 15 16 typedef struct MD5Context MD5_CTX; 17 18 struct MD5Context { 19 uint32 buf[4]; 20 uint32 bits[2]; 21 uint32 in[16]; 22 }; 23 24 void MD5Init(struct MD5Context* context); 25 void MD5Update(struct MD5Context* context, const uint8* data, size_t len); 26 void MD5Final(unsigned char digest[16], struct MD5Context* ctx); 27 void MD5Transform(uint32 buf[4], const uint32 in[16]); 28 29 // Start MD5 accumulation. Set bit count to 0 and buffer to mysterious 30 // initialization constants. 31 void MD5Init(MD5Context* context) { 32 context->buf[0] = 0x67452301; 33 context->buf[1] = 0xefcdab89; 34 context->buf[2] = 0x98badcfe; 35 context->buf[3] = 0x10325476; 36 context->bits[0] = 0; 37 context->bits[1] = 0; 38 } 39 40 // Update context to reflect the concatenation of another buffer full of bytes. 41 void MD5Update(MD5Context* context, const uint8* data, size_t len) { 42 // Update bitcount. 43 uint32 t = context->bits[0]; 44 if ((context->bits[0] = t + (static_cast<uint32>(len) << 3)) < t) { 45 context->bits[1]++; // Carry from low to high. 46 } 47 context->bits[1] += len >> 29; 48 t = (t >> 3) & 0x3f; // Bytes already in shsInfo->data. 49 50 // Handle any leading odd-sized chunks. 51 if (t) { 52 uint8* p = reinterpret_cast<uint8*>(context->in) + t; 53 54 t = 64 - t; 55 if (len < t) { 56 memcpy(p, data, len); 57 return; 58 } 59 memcpy(p, data, t); 60 MD5Transform(context->buf, context->in); 61 data += t; 62 len -= t; 63 } 64 65 // Process data in 64-byte chunks. 66 while (len >= 64) { 67 memcpy(context->in, data, 64); 68 MD5Transform(context->buf, context->in); 69 data += 64; 70 len -= 64; 71 } 72 73 // Handle any remaining bytes of data. 74 memcpy(context->in, data, len); 75 } 76 77 // Final wrapup - pad to 64-byte boundary with the bit pattern. 78 // 1 0* (64-bit count of bits processed, MSB-first) 79 void MD5Final(uint8 digest[16], MD5Context* ctx) { 80 // Compute number of bytes mod 64. 81 uint32 count = (ctx->bits[0] >> 3) & 0x3F; 82 83 // Set the first char of padding to 0x80. This is safe since there is 84 // always at least one byte free. 85 uint8* p = reinterpret_cast<uint8*>(ctx->in) + count; 86 *p++ = 0x80; 87 88 // Bytes of padding needed to make 64 bytes. 89 count = 64 - 1 - count; 90 91 // Pad out to 56 mod 64. 92 if (count < 8) { 93 // Two lots of padding: Pad the first block to 64 bytes. 94 memset(p, 0, count); 95 MD5Transform(ctx->buf, ctx->in); 96 97 // Now fill the next block with 56 bytes. 98 memset(ctx->in, 0, 56); 99 } else { 100 // Pad block to 56 bytes. 101 memset(p, 0, count - 8); 102 } 103 104 // Append length in bits and transform. 105 ctx->in[14] = ctx->bits[0]; 106 ctx->in[15] = ctx->bits[1]; 107 108 MD5Transform(ctx->buf, ctx->in); 109 memcpy(digest, ctx->buf, 16); 110 memset(ctx, 0, sizeof(*ctx)); // In case it's sensitive. 111 } 112 113 // The four core functions - F1 is optimized somewhat. 114 // #define F1(x, y, z) (x & y | ~x & z) 115 #define F1(x, y, z) (z ^ (x & (y ^ z))) 116 #define F2(x, y, z) F1(z, x, y) 117 #define F3(x, y, z) (x ^ y ^ z) 118 #define F4(x, y, z) (y ^ (x | ~z)) 119 120 // This is the central step in the MD5 algorithm. 121 #define MD5STEP(f, w, x, y, z, data, s) \ 122 (w += f(x, y, z) + data, w = w << s | w >> (32 - s), w += x) 123 124 #if defined(__clang__) && defined(__has_attribute) 125 #if __has_attribute(no_sanitize) 126 #define DDEPTH_NO_UNSIGNED_OVERFLOW_CHECK \ 127 __attribute__((no_sanitize("unsigned-integer-overflow"))) 128 #endif 129 #endif 130 131 #ifndef DDEPTH_NO_UNSIGNED_OVERFLOW_CHECK 132 #define DDEPTH_NO_UNSIGNED_OVERFLOW_CHECK 133 #endif 134 135 // The core of the MD5 algorithm, this alters an existing MD5 hash to 136 // reflect the addition of 16 longwords of new data. MD5Update blocks 137 // the data and converts bytes into longwords for this routine. 138 DDEPTH_NO_UNSIGNED_OVERFLOW_CHECK void MD5Transform(uint32 buf[4], 139 const uint32 in[16]) { 140 uint32 a = buf[0]; 141 uint32 b = buf[1]; 142 uint32 c = buf[2]; 143 uint32 d = buf[3]; 144 145 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7); 146 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12); 147 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17); 148 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22); 149 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7); 150 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12); 151 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17); 152 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22); 153 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7); 154 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12); 155 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17); 156 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22); 157 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7); 158 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12); 159 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17); 160 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22); 161 162 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5); 163 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9); 164 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14); 165 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); 166 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5); 167 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9); 168 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14); 169 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); 170 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5); 171 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9); 172 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14); 173 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20); 174 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5); 175 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); 176 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14); 177 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); 178 179 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4); 180 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11); 181 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16); 182 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23); 183 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4); 184 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); 185 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); 186 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23); 187 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4); 188 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11); 189 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16); 190 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23); 191 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4); 192 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11); 193 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); 194 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23); 195 196 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6); 197 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10); 198 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15); 199 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21); 200 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6); 201 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); 202 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15); 203 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21); 204 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); 205 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); 206 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15); 207 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21); 208 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6); 209 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10); 210 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); 211 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21); 212 buf[0] += a; 213 buf[1] += b; 214 buf[2] += c; 215 buf[3] += d; 216 } 217 218 void MD5(const uint8_t* to_hash, size_t to_hash_length, uint8_t* output) { 219 MD5Context md5_context; 220 MD5Init(&md5_context); 221 MD5Update(&md5_context, to_hash, to_hash_length); 222 MD5Final(output, &md5_context); 223 } 224 225 } // namespace 226 227 string MD5Hash(const string& to_hash) { 228 std::vector<uint8_t> buffer; 229 buffer.resize(kMd5DigestSize); 230 MD5(reinterpret_cast<const uint8_t*>(to_hash.data()), to_hash.length(), 231 &buffer[0]); 232 return dynamic_depth::b2a_hex(reinterpret_cast<const char*>(&buffer[0]), 233 kMd5DigestSize); 234 } 235 236 } // namespace xmpmeta 237 } // namespace dynamic_depth 238
