CeDOS - Commit ae0f4fa1

shell: Added MD5 hash program
Celina Sophie Kalus
Sun, 26 Nov 2023 22:22:12 +0100
1 files changed, 93 insertions(+), 0 deletions(-)

jump to
A src/shell/md5.c

@@ -0,0 +1,93 @@

+#include "cedos.h" +#include "stdio.h" +#include "string.h" + +const uint32_t K[64] = { + 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, + 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501, + 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, + 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821, + 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, + 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8, + 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, + 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a, + 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, + 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, + 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05, + 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665, + 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, + 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1, + 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, + 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391 }; + +const uint32_t s[64] = { + 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, + 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, + 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, + 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21 }; + +#define MD5_CHUNK_SIZE 512 + +#define lrotate32(x, i) ((x << i) | (x >> (32 - i))) + +void main(char *args) { + FILE* file = fopen(args, "r"); + + if (file == NULL) { + printf("Could not find file: %s\n", args); + return; + } + + char buffer[MD5_CHUNK_SIZE]; + uint32_t hash[4] = { 0x01234567, 0x89abcdef, 0xfedcba98, 0x76543210 }; + + int run = 1; + while (run) { + memset(buffer, 0, MD5_CHUNK_SIZE); + int size = fread(buffer, 1, MD5_CHUNK_SIZE, file); + if (size < MD5_CHUNK_SIZE) { + buffer[size] = 0x80; + run = 0; + } + + uint32_t *M = buffer; + uint32_t chunk_hash[4] = { hash[0], hash[1], hash[2], hash[3] }; + uint32_t F, g; + + for (int i = 0; i < 64; i++) { + if (i < 16) { + F = (chunk_hash[1] & chunk_hash[2]) + | ((~chunk_hash[1]) & chunk_hash[3]); + g = i; + } else if (i < 32) { + F = (chunk_hash[3] & chunk_hash[1]) + | ((~chunk_hash[3]) & chunk_hash[2]); + g = (5 * i + 1) % 16; + } else if (i < 48) { + F = chunk_hash[1] ^ chunk_hash[2] ^ chunk_hash[3]; + g = (3 * i + 5) % 16; + } else { + F = chunk_hash[2] ^ (chunk_hash[2] | (~chunk_hash[3])); + g = (7 * i) % 16; + } + + F = F + chunk_hash[0] + K[i] + M[g]; + chunk_hash[0] = chunk_hash[3]; + chunk_hash[3] = chunk_hash[2]; + chunk_hash[2] = chunk_hash[1]; + chunk_hash[1] = chunk_hash[1] + lrotate32(F, s[i]); + } + + hash[0] += chunk_hash[0]; + hash[1] += chunk_hash[1]; + hash[2] += chunk_hash[2]; + hash[3] += chunk_hash[3]; + } + + uint8_t *digest = (uint8_t *)(hash); + + for (int i = 0; i < 16; i++) { + printf("%x", digest[i]); + } + printf("\n"); +}