md5.c
1 /* 2 * Copyright (C) 2021 - This file is part of libecc project 3 * 4 * Authors: 5 * Ryad BENADJILA <ryadbenadjila@gmail.com> 6 * Arnaud EBALARD <arnaud.ebalard@ssi.gouv.fr> 7 * 8 * This software is licensed under a dual BSD and GPL v2 license. 9 * See LICENSE file at the root folder of the project. 10 */ 11 #include "md5.h" 12 13 /* All the inner MD-5 operations */ 14 static const u32 K_MD5[64] = { 15 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501, 16 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821, 17 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8, 18 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a, 19 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, 20 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05, 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665, 21 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1, 22 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391 23 }; 24 25 static const u8 R_MD5[64] = { 26 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 27 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 28 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 29 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21 30 }; 31 32 #define F_MD5(x, y, z) (((x) & (y)) | ((~(x)) & (z))) 33 #define G_MD5(x, y, z) (((x) & (z)) | ((y) & (~(z)))) 34 #define H_MD5(x, y, z) ((x) ^ (y) ^ (z)) 35 #define I_MD5(x, y, z) ((y) ^ ((x) | ((~z)))) 36 37 /* SHA-2 core processing. Returns 0 on success, -1 on error. */ 38 ATTRIBUTE_WARN_UNUSED_RET static inline int md5_process(md5_context *ctx, 39 const u8 data[MD5_BLOCK_SIZE]) 40 { 41 u32 A, B, C, D, tmp; 42 u32 W[16]; 43 int ret; 44 unsigned int i; 45 46 MUST_HAVE((data != NULL), ret, err); 47 MD5_HASH_CHECK_INITIALIZED(ctx, ret, err); 48 49 /* Init our inner variables */ 50 A = ctx->md5_state[0]; 51 B = ctx->md5_state[1]; 52 C = ctx->md5_state[2]; 53 D = ctx->md5_state[3]; 54 55 /* Load data */ 56 for (i = 0; i < 16; i++) { 57 GET_UINT32_LE(W[i], data, (4 * i)); 58 } 59 for (i = 0; i < 64; i++) { 60 u32 f, g; 61 if(i <= 15){ 62 f = F_MD5(B, C, D); 63 g = i; 64 } 65 else if((i >= 16) && (i <= 31)){ 66 f = G_MD5(B, C, D); 67 g = (((5 * i) + 1) % 16); 68 } 69 else if((i >= 32) && (i <= 47)){ 70 f = H_MD5(B, C, D); 71 g = (((3 * i) + 5) % 16); 72 } 73 else{ 74 f = I_MD5(B, C, D); 75 g = ((7 * i) % 16); 76 } 77 tmp = D; 78 D = C; 79 C = B; 80 B += ROTL_MD5((A + f + K_MD5[i] + W[g]), R_MD5[i]); 81 A = tmp; 82 } 83 84 /* Update state */ 85 ctx->md5_state[0] += A; 86 ctx->md5_state[1] += B; 87 ctx->md5_state[2] += C; 88 ctx->md5_state[3] += D; 89 90 ret = 0; 91 92 err: 93 return ret; 94 } 95 96 /* Init hash function. Returns 0 on success, -1 on error. */ 97 ATTRIBUTE_WARN_UNUSED_RET int md5_init(md5_context *ctx) 98 { 99 int ret; 100 101 MUST_HAVE((ctx != NULL), ret, err); 102 103 /* Sanity check on size */ 104 MUST_HAVE((MD5_DIGEST_SIZE <= MAX_DIGEST_SIZE), ret, err); 105 106 ctx->md5_total = 0; 107 ctx->md5_state[0] = 0x67452301; 108 ctx->md5_state[1] = 0xEFCDAB89; 109 ctx->md5_state[2] = 0x98BADCFE; 110 ctx->md5_state[3] = 0x10325476; 111 112 /* Tell that we are initialized */ 113 ctx->magic = MD5_HASH_MAGIC; 114 115 ret = 0; 116 117 err: 118 return ret; 119 } 120 121 ATTRIBUTE_WARN_UNUSED_RET int md5_update(md5_context *ctx, const u8 *input, u32 ilen) 122 { 123 const u8 *data_ptr = input; 124 u32 remain_ilen = ilen; 125 u16 fill; 126 u8 left; 127 int ret; 128 129 MUST_HAVE((input != NULL) || (ilen == 0), ret, err); 130 MD5_HASH_CHECK_INITIALIZED(ctx, ret, err); 131 132 /* Nothing to process, return */ 133 if (ilen == 0) { 134 ret = 0; 135 goto err; 136 } 137 138 /* Get what's left in our local buffer */ 139 left = (ctx->md5_total & 0x3F); 140 fill = (u16)(MD5_BLOCK_SIZE - left); 141 142 ctx->md5_total += ilen; 143 144 if ((left > 0) && (remain_ilen >= fill)) { 145 /* Copy data at the end of the buffer */ 146 ret = local_memcpy(ctx->md5_buffer + left, data_ptr, fill); EG(ret, err); 147 ret = md5_process(ctx, ctx->md5_buffer); EG(ret, err); 148 data_ptr += fill; 149 remain_ilen -= fill; 150 left = 0; 151 } 152 153 while (remain_ilen >= MD5_BLOCK_SIZE) { 154 ret = md5_process(ctx, data_ptr); EG(ret, err); 155 data_ptr += MD5_BLOCK_SIZE; 156 remain_ilen -= MD5_BLOCK_SIZE; 157 } 158 159 if (remain_ilen > 0) { 160 ret = local_memcpy(ctx->md5_buffer + left, data_ptr, remain_ilen); EG(ret, err); 161 } 162 163 ret = 0; 164 165 err: 166 return ret; 167 } 168 169 /* Finalize. Returns 0 on success, -1 on error.*/ 170 ATTRIBUTE_WARN_UNUSED_RET int md5_final(md5_context *ctx, u8 output[MD5_DIGEST_SIZE]) 171 { 172 unsigned int block_present = 0; 173 u8 last_padded_block[2 * MD5_BLOCK_SIZE]; 174 int ret; 175 176 MUST_HAVE((output != NULL), ret, err); 177 MD5_HASH_CHECK_INITIALIZED(ctx, ret, err); 178 179 /* Fill in our last block with zeroes */ 180 ret = local_memset(last_padded_block, 0, sizeof(last_padded_block)); EG(ret, err); 181 182 /* This is our final step, so we proceed with the padding */ 183 block_present = ctx->md5_total % MD5_BLOCK_SIZE; 184 if (block_present != 0) { 185 /* Copy what's left in our temporary context buffer */ 186 ret = local_memcpy(last_padded_block, ctx->md5_buffer, 187 block_present); EG(ret, err); 188 } 189 190 /* Put the 0x80 byte, beginning of padding */ 191 last_padded_block[block_present] = 0x80; 192 193 /* Handle possible additional block */ 194 if (block_present > (MD5_BLOCK_SIZE - 1 - sizeof(u64))) { 195 /* We need an additional block */ 196 PUT_UINT64_LE(8 * ctx->md5_total, last_padded_block, 197 (2 * MD5_BLOCK_SIZE) - sizeof(u64)); 198 ret = md5_process(ctx, last_padded_block); EG(ret, err); 199 ret = md5_process(ctx, last_padded_block + MD5_BLOCK_SIZE); EG(ret, err); 200 } else { 201 /* We do not need an additional block */ 202 PUT_UINT64_LE(8 * ctx->md5_total, last_padded_block, 203 MD5_BLOCK_SIZE - sizeof(u64)); 204 ret = md5_process(ctx, last_padded_block); EG(ret, err); 205 } 206 207 /* Output the hash result */ 208 PUT_UINT32_LE(ctx->md5_state[0], output, 0); 209 PUT_UINT32_LE(ctx->md5_state[1], output, 4); 210 PUT_UINT32_LE(ctx->md5_state[2], output, 8); 211 PUT_UINT32_LE(ctx->md5_state[3], output, 12); 212 213 /* Tell that we are uninitialized */ 214 ctx->magic = WORD(0); 215 216 ret = 0; 217 218 err: 219 return ret; 220 } 221 222 223 /* 224 * Scattered version performing init/update/finalize on a vector of buffers 225 * 'inputs' with the length of each buffer passed via 'ilens'. The function 226 * loops on pointers in 'inputs' until it finds a NULL pointer. The function 227 * returns 0 on success, -1 on error. 228 */ 229 ATTRIBUTE_WARN_UNUSED_RET int md5_scattered(const u8 **inputs, const u32 *ilens, 230 u8 output[MD5_DIGEST_SIZE]) 231 { 232 md5_context ctx; 233 int ret, pos = 0; 234 235 MUST_HAVE((inputs != NULL) && (ilens != NULL) && (output != NULL), ret, err); 236 237 ret = md5_init(&ctx); EG(ret, err); 238 239 while (inputs[pos] != NULL) { 240 ret = md5_update(&ctx, inputs[pos], ilens[pos]); EG(ret, err); 241 pos += 1; 242 } 243 244 ret = md5_final(&ctx, output); 245 246 err: 247 return ret; 248 } 249 250 /* 251 * Single call version performing init/update/final on given input. 252 * Returns 0 on success, -1 on error. 253 */ 254 ATTRIBUTE_WARN_UNUSED_RET int md5(const u8 *input, u32 ilen, u8 output[MD5_DIGEST_SIZE]) 255 { 256 md5_context ctx; 257 int ret; 258 259 ret = md5_init(&ctx); EG(ret, err); 260 ret = md5_update(&ctx, input, ilen); EG(ret, err); 261 ret = md5_final(&ctx, output); 262 263 err: 264 return ret; 265 }