diff options
Diffstat (limited to 'lib/lib4.c')
| -rw-r--r-- | lib/lib4.c | 196 |
1 files changed, 190 insertions, 6 deletions
@@ -22,6 +22,126 @@ int aes_ctr_edit(char *ciphertext, int ciphertext_length, int offset, char *newt } +unsigned int left_rotate(int shift, int value) +{ + // TODO make use of the x86 instruction rol, ror + unsigned int ret = value; + unsigned int mask = 0xFFFFFFFF << shift; + ret = ret << shift; + ret |= ((value & mask) >> (32-shift)); + return ret; +} + +void sha1_helper_copy_chunk(char *chunk, int *dest) +{ + int i; + for(i=0;i<16;i++) { + memcpy(&dest[i], &chunk[i], 4); + } +} + +void sha1_hash(char *text, int text_length) +{ + unsigned char *padding; + char *hash; + int padding_len = sha1_padding(text_length, &padding); + + char *to_hash = malloc(text_length + padding_len); + + memcpy(to_hash, text, text_length); + memcpy(&to_hash[text_length], padding, padding_len); + hash_sha1_core(to_hash, (text_length + padding_len), &hash); + int i; + for(i=0;i<64;i++) + printf("%02x", hash[i]); + printf("\n"); +} + +void hash_sha1_core(char *text, int text_length, char **sha1_hash) +{ + *sha1_hash = malloc(20); + int i,j; + unsigned int h0 = 0x67452301; + unsigned int h1 = 0xEFCDAB89; + unsigned int h2 = 0x98BADCFE; + unsigned int h3 = 0x10325476; + unsigned int h4 = 0xC3D2E1F0; + + unsigned int temp; + int chunks = (text_length*8) / 512; + unsigned int w[80]; + unsigned int a,b,c,d,e,f,k; + char *chunk; + + for(i=0;i<chunks;i++) { + // chunk is text[i*512] + // fill the first w[0]...w[15] + sha1_helper_copy_chunk(&text[i*512], w); + + for(j=16;j<80;j++) { + w[j] = (w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16]); + w[j] = left_rotate(1, w[j]); + } + + a = h0; + b = h1; + c = h2; + d = h3; + c = h4; + + for(j=0;j<80;j++) { + if (i >= 0 && i <= 19) { + f = (b & c) | ((~b) & d); + k = 0x5A827999; + } + else if (i >= 20 && i <= 39) { + f = b ^ c ^ d; + k = 0x6ED9EBA1; + } + else if (i>= 40 && i <= 59) { + f = (b & c) | (b & d) | (c & d); + k = 0x8F1BBCDC; + } + else if (i >= 60 && i <= 79) { + f = b ^ c ^ d; + k = 0xCA62C1D6; + } + + temp = left_rotate(5 ,a); + temp += f + e + k + w[j]; + e = d; + d = c; + c = left_rotate(30, b); + b = a; + a = temp; + + } + + h0 += a; + h1 += b; + h2 += c; + h3 += d; + h4 += e; + } + + // copy h_i into sha_hash + memcpy(*sha1_hash, &h0, 4); + memcpy(&((*sha1_hash)[4]), &h1, 4); + memcpy(&((*sha1_hash)[8]), &h2, 4); + memcpy(&((*sha1_hash)[12]), &h3, 4); + memcpy(&((*sha1_hash)[16]), &h4, 4); +} + +void sha1_set_magic_nr(SHA1Context *sh, unsigned int *magic) +{ + sh->Message_Digest[0] = magic[0]; + sh->Message_Digest[1] = magic[1]; + sh->Message_Digest[2] = magic[2]; + sh->Message_Digest[3] = magic[3]; + sh->Message_Digest[4] = magic[4]; +} + + void sha1_hmac(unsigned int *mac, unsigned char *message, unsigned int msg_len, unsigned char *key, unsigned int key_len) { @@ -47,11 +167,21 @@ int sha1_hmac_verify(unsigned int *mac, unsigned char *msg, unsigned int msg_len sha1_hmac(com_mac, msg, msg_len, key, key_len); + printf("mac of msg is:\n"); + int i; + for(i=0;i<5;i++) + printf("%02x", com_mac[i]); + printf("\n"); + printf("to compate with\n"); + for(i=0;i<5;i++) + printf("%02x", mac[i]); + printf("\n"); + return !memcmp(com_mac, mac, 20); } -int sha1_padding(unsigned long msg_len, char **result) +int sha1_padding(unsigned long msg_len, unsigned char **result) { int i; unsigned int padding_len = 64 - (msg_len % 64); @@ -62,8 +192,7 @@ int sha1_padding(unsigned long msg_len, char **result) memset((*result), 0x00, padding_len); // append 1 - memset(&(*result)[0], 0x80, 1); - //(*result)[0] = 0x80; + (*result)[0] = 0x80; // write the 8 byte msg_len at the end bytewise for(i=0;i<8;i++) { @@ -77,12 +206,67 @@ void sha1_hmac_forge(unsigned int *mac, unsigned char *text, unsigned int text_l unsigned int *sha1_registers) { SHA1Context sh; - SHA1Reset(&sh); + SHA1Reset_Mod(&sh, sha1_registers); - sha1_set_magic_nr(&sh, sha1_registers); SHA1Input(&sh, text, text_len); - SHA1Result(&sh); + SHA1Result_Forged(&sh); memcpy(mac, &(sh.Message_Digest), 20); } + +void md4_prefix_key_mac(uint32_t **mac, unsigned char *text, unsigned int text_len, + unsigned char *key, unsigned int key_len) +{ + char *res = malloc(text_len + key_len); + + memcpy(res, text, text_len); + memcpy(res+text_len, key, key_len); + + MD4(res, (text_len + key_len), mac, NULL); +} + +int md4_prefix_key_verify(uint32_t *mac, unsigned char *text, unsigned int text_len, + unsigned char *key, unsigned int key_len) +{ + uint32_t *hash; + + MD4(text, text_len, &hash, NULL); + printf("computed mac is:\n"); + int i; + for(i=0;i<4;i++) + printf("%02x", hash[i]); + printf("\n"); + return !memcmp(hash, mac, 4*sizeof(uint32_t)); +} + +void md4_prefix_key_forge(uint32_t **mac, unsigned char *text, unsigned int text_len, + unsigned int *md4_registers) +{ + MD4(text, text_len, mac, md4_registers); +} + +uint32_t stringToUint32(char *s){ + uint32_t l; + int i; + l=0; + for(i=0; i<4; i++){ + l = l|(((uint32_t)((unsigned char)s[i]))<<(8*(3-i))); + } + return l; +} + +uint32_t changeEndianness(uint32_t x){ + return ((x & 0xFF) << 24) | ((x & 0xFF00) << 8) | ((x & 0xFF0000) >> 8) | ((x & 0xFF000000) >> 24); +} + +int md4_padding(unsigned long msg_len, unsigned char **result) +{ + int len = sha1_padding(msg_len, result); + int i; + //change endianess + for(i=0;i<len;i+=4) + (*result)[i] = changeEndianness(stringToUint32(&(*result)[i])); + + return len; +} |