Clean up header organization

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;
+}