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Diffstat (limited to 'src/generic/md5.cpp')
| -rw-r--r-- | src/generic/md5.cpp | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/src/generic/md5.cpp b/src/generic/md5.cpp new file mode 100644 index 0000000..a626dc5 --- /dev/null +++ b/src/generic/md5.cpp @@ -0,0 +1,234 @@ +#include "md5.hpp" + +#include <cstring> + +#include "../compat/rawmem.hpp" + +#include "../strings/xstring.hpp" +#include "../strings/vstring.hpp" + +#include "random.hpp" + +#include "../poison.hpp" + +// auxilary data +/* +sin() constant table +#Reformatted output of: +echo 'scale=40; obase=16; for (i=1;i<=64;i++) print 2^32 * sin(i), "\n"' | +bc | sed 's/^-//;s/^/0x/;s/\..*$/,/' +*/ +static +const uint32_t T[64] = +{ + // used by round 1 + 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, //0 + 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501, //4 + 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, //8 + 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821, //12 + // used by round 2 + 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, //16 + 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8, //20 + 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, //24 + 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a, //28 + // used by round 3 + 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, //32 + 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, //36 + 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05, //40 + 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665, //44 + // used by round 4 + 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, //48 + 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1, //52 + 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, //56 + 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391, //60 +}; + +// auxilary functions +// note - the RFC defines these by non-CS conventions: or=v, and=(empty) +static +uint32_t rotate_left(uint32_t val, unsigned shift) +{ + return val << shift | val >> (32 - shift); +} + +static +uint32_t F(uint32_t X, uint32_t Y, uint32_t Z) +{ + return (X & Y) | (~X & Z); +} +static +uint32_t G(uint32_t X, uint32_t Y, uint32_t Z) +{ + return (X & Z) | (Y & ~Z); +} +static +uint32_t H(uint32_t X, uint32_t Y, uint32_t Z) +{ + return X ^ Y ^ Z; +} +static +uint32_t I(uint32_t X, uint32_t Y, uint32_t Z) +{ + return Y ^ (X | ~Z); +} + +static +const struct +{ + uint8_t k : 4; + uint8_t : 0; + uint8_t s : 5; +// uint8_t i : 6; just increments constantly, from 1 .. 64 over all rounds +} +MD5_round1[16] = +{ + { 0, 7}, { 1, 12}, { 2, 17}, { 3, 22}, + { 4, 7}, { 5, 12}, { 6, 17}, { 7, 22}, + { 8, 7}, { 9, 12}, {10, 17}, {11, 22}, + {12, 7}, {13, 12}, {14, 17}, {15, 22}, +}, +MD5_round2[16] = +{ + { 1, 5}, { 6, 9}, {11, 14}, { 0, 20}, + { 5, 5}, {10, 9}, {15, 14}, { 4, 20}, + { 9, 5}, {14, 9}, { 3, 14}, { 8, 20}, + {13, 5}, { 2, 9}, { 7, 14}, {12, 20}, +}, +MD5_round3[16] = +{ + { 5, 4}, { 8, 11}, {11, 16}, {14, 23}, + { 1, 4}, { 4, 11}, { 7, 16}, {10, 23}, + {13, 4}, { 0, 11}, { 3, 16}, { 6, 23}, + { 9, 4}, {12, 11}, {15, 16}, { 2, 23}, +}, +MD5_round4[16] = +{ + { 0, 6}, { 7, 10}, {14, 15}, { 5, 21}, + {12, 6}, { 3, 10}, {10, 15}, { 1, 21}, + { 8, 6}, {15, 10}, { 6, 15}, {13, 21}, + { 4, 6}, {11, 10}, { 2, 15}, { 9, 21}, +}; + + +void MD5_init(MD5_state* state) +{ + // in the RFC, these are specified as bytes, interpreted as little-endian + state->val[0] = 0x67452301; + state->val[1] = 0xEFCDAB89; + state->val[2] = 0x98BADCFE; + state->val[3] = 0x10325476; +} + +#define X block.data + +void MD5_do_block(MD5_state* state, MD5_block block) +{ +#define a state->val[(16 - i) % 4] +#define b state->val[(17 - i) % 4] +#define c state->val[(18 - i) % 4] +#define d state->val[(19 - i) % 4] + // save the values + const MD5_state saved = *state; + // round 1 + for (int i = 0; i < 16; i++) + { +#define k MD5_round1[i].k +#define s MD5_round1[i].s + a = b + rotate_left(a + F(b, c, d) + X[k] + T[i + 0x0], s); +#undef k +#undef s + } + // round 2 + for (int i = 0; i < 16; i++) + { +#define k MD5_round2[i].k +#define s MD5_round2[i].s + a = b + rotate_left(a + G(b, c, d) + X[k] + T[i + 0x10], s); +#undef k +#undef s + } + // round 3 + for (int i = 0; i < 16; i++) + { +#define k MD5_round3[i].k +#define s MD5_round3[i].s + a = b + rotate_left(a + H(b, c, d) + X[k] + T[i + 0x20], s); +#undef k +#undef s + } + // round 4 + for (int i = 0; i < 16; i++) + { +#define k MD5_round4[i].k +#define s MD5_round4[i].s + a = b + rotate_left(a + I(b, c, d) + X[k] + T[i + 0x30], s); +#undef k +#undef s + } + // adjust state based on original + state->val[0] += saved.val[0]; + state->val[1] += saved.val[1]; + state->val[2] += saved.val[2]; + state->val[3] += saved.val[3]; +#undef a +#undef b +#undef c +#undef d +} + +void MD5_to_bin(MD5_state state, md5_binary& out) +{ + for (int i = 0; i < 0x10; i++) + out[i] = state.val[i / 4] >> 8 * (i % 4); +} + +static +const char hex[] = "0123456789abcdef"; + +void MD5_to_str(MD5_state state, md5_string& out_) +{ + md5_binary bin; + MD5_to_bin(state, bin); + char out[0x20]; + for (int i = 0; i < 0x10; i++) + out[2 * i] = hex[bin[i] >> 4], + out[2 * i + 1] = hex[bin[i] & 0xf]; + out_ = stringish<md5_string>(XString(out, out + 0x20, nullptr)); +} + +MD5_state MD5_from_string(XString msg) +{ + MD5_state state; + MD5_init(&state); + MD5_block block; + const uint64_t msg_full_len = msg.size(); + while (msg.size() >= 64) + { + for (int i = 0; i < 0x10; i++) + X[i] = msg[4 * i + 0] | msg[4 * i + 1] << 8 | msg[4 * i + 2] << 16 | msg[4 * i + 3] << 24; + MD5_do_block(&state, block); + msg = msg.xslice_t(64); + } + // now pad 1-512 bits + the 64-bit length - may be two blocks + uint8_t buf[0x40] = {}; + really_memcpy(buf, reinterpret_cast<const uint8_t *>(msg.data()), msg.size()); + buf[msg.size()] = 0x80; // a single one bit + if (64 - msg.size() > 8) + { + for (int i = 0; i < 8; i++) + buf[0x38 + i] = (msg_full_len * 8) >> (i * 8); + } + for (int i = 0; i < 0x10; i++) + X[i] = buf[4 * i + 0] | buf[4 * i + 1] << 8 | buf[4 * i + 2] << 16 | buf[4 * i + 3] << 24; + MD5_do_block(&state, block); + if (64 - msg.size() <= 8) + { + really_memset0(buf, 0x38); + for (int i = 0; i < 8; i++) + buf[0x38 + i] = (msg_full_len * 8) >> (i * 8); + for (int i = 0; i < 0x10; i++) + X[i] = buf[4 * i + 0] | buf[4 * i + 1] << 8 | buf[4 * i + 2] << 16 | buf[4 * i + 3] << 24; + MD5_do_block(&state, block); + } + return state; +} |