+
+#include "secure.h"
+
+/*****************************************************************/
+
+/*
+ * This code implements the MD5 message-digest algorithm.
+ * The algorithm is due to Ron Rivest. This code was
+ * written by Colin Plumb in 1993, no copyright is claimed.
+ * This code is in the public domain; do with it what you wish.
+ *
+ * Equivalent code is available from RSA Data Security, Inc.
+ * This code has been tested against that, and is equivalent,
+ * except that you don't need to include two pages of legalese
+ * with every copy.
+ *
+ * To compute the message digest of a chunk of bytes, declare an
+ * MD5Context structure, pass it to MD5Init, call MD5Update as
+ * needed on buffers full of bytes, and then call MD5Final, which
+ * will fill a supplied 16-byte array with the digest.
+ */
+
+typedef unsigned long word32;
+typedef unsigned char byte;
+
+struct xMD5Context {
+ word32 buf[4];
+ word32 bytes[2];
+ word32 in[16];
+};
+
+void xMD5Init(struct xMD5Context *context);
+void xMD5Update(struct xMD5Context *context, byte const *buf, int len);
+void xMD5Final(byte digest[16], struct xMD5Context *context);
+void xMD5Transform(word32 buf[4], word32 const in[16]);
+
+
+/*
+ * Shuffle the bytes into little-endian order within words, as per the
+ * MD5 spec. Note: this code works regardless of the byte order.
+ */
+void
+byteSwap(word32 *buf, unsigned words)
+{
+ byte *p = (byte *)buf;
+
+ do {
+ *buf++ = (word32)((unsigned)p[3] << 8 | p[2]) << 16 |
+ ((unsigned)p[1] << 8 | p[0]);
+ p += 4;
+ } while (--words);
+}
+
+/*
+ * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
+ * initialization constants.
+ */
+void
+xMD5Init(struct xMD5Context *ctx)
+{
+ ctx->buf[0] = 0x67452301;
+ ctx->buf[1] = 0xefcdab89;
+ ctx->buf[2] = 0x98badcfe;
+ ctx->buf[3] = 0x10325476;
+
+ ctx->bytes[0] = 0;
+ ctx->bytes[1] = 0;
+}
+
+/*
+ * Update context to reflect the concatenation of another buffer full
+ * of bytes.
+ */
+void
+xMD5Update(struct xMD5Context *ctx, byte const *buf, int len)
+{
+ word32 t;
+
+ /* Update byte count */
+
+ t = ctx->bytes[0];
+ if ((ctx->bytes[0] = t + len) < t)
+ ctx->bytes[1]++; /* Carry from low to high */
+
+ t = 64 - (t & 0x3f); /* Space available in ctx->in (at least 1) */
+ if ((unsigned)t > len) {
+ bcopy(buf, (byte *)ctx->in + 64 - (unsigned)t, len);
+ return;
+ }
+ /* First chunk is an odd size */
+ bcopy(buf,(byte *)ctx->in + 64 - (unsigned)t, (unsigned)t);
+ byteSwap(ctx->in, 16);
+ xMD5Transform(ctx->buf, ctx->in);
+ buf += (unsigned)t;
+ len -= (unsigned)t;
+
+ /* Process data in 64-byte chunks */
+ while (len >= 64) {
+ bcopy(buf, ctx->in, 64);
+ byteSwap(ctx->in, 16);
+ xMD5Transform(ctx->buf, ctx->in);
+ buf += 64;
+ len -= 64;
+ }
+
+ /* Handle any remaining bytes of data. */
+ bcopy(buf, ctx->in, len);
+}
+
+/*
+ * Final wrapup - pad to 64-byte boundary with the bit pattern
+ * 1 0* (64-bit count of bits processed, MSB-first)
+ */
+void
+xMD5Final(byte digest[16], struct xMD5Context *ctx)
+{
+ int count = (int)(ctx->bytes[0] & 0x3f); /* Bytes in ctx->in */
+ byte *p = (byte *)ctx->in + count; /* First unused byte */
+
+ /* Set the first char of padding to 0x80. There is always room. */
+ *p++ = 0x80;
+
+ /* Bytes of padding needed to make 56 bytes (-8..55) */
+ count = 56 - 1 - count;
+
+ if (count < 0) { /* Padding forces an extra block */
+ bzero(p, count+8);
+ byteSwap(ctx->in, 16);
+ xMD5Transform(ctx->buf, ctx->in);
+ p = (byte *)ctx->in;
+ count = 56;
+ }
+ bzero(p, count+8);
+ byteSwap(ctx->in, 14);
+
+ /* Append length in bits and transform */
+ ctx->in[14] = ctx->bytes[0] << 3;
+ ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
+ xMD5Transform(ctx->buf, ctx->in);
+
+ byteSwap(ctx->buf, 4);
+ bcopy(ctx->buf, digest, 16);
+ bzero(ctx,sizeof(ctx));
+}
+
+
+/* The four core functions - F1 is optimized somewhat */
+
+/* #define F1(x, y, z) (x & y | ~x & z) */
+#define F1(x, y, z) (z ^ (x & (y ^ z)))
+#define F2(x, y, z) F1(z, x, y)
+#define F3(x, y, z) (x ^ y ^ z)
+#define F4(x, y, z) (y ^ (x | ~z))
+
+/* This is the central step in the MD5 algorithm. */
+#define MD5STEP(f,w,x,y,z,in,s) \
+ (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x)
+
+/*
+ * The core of the MD5 algorithm, this alters an existing MD5 hash to
+ * reflect the addition of 16 longwords of new data. MD5Update blocks
+ * the data and converts bytes into longwords for this routine.
+ */
+void
+xMD5Transform(word32 buf[4], word32 const in[16])
+{
+ register word32 a, b, c, d;
+
+ a = buf[0];
+ b = buf[1];
+ c = buf[2];
+ d = buf[3];
+
+ MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
+ MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
+ MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
+ MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
+ MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
+ MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
+ MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
+ MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
+ MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
+ MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
+ MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
+ MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
+ MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
+ MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
+ MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
+ MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
+
+ MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
+ MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
+ MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
+ MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
+ MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
+ MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
+ MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
+ MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
+ MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
+ MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
+ MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
+ MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
+ MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
+ MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
+ MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
+ MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
+
+ MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
+ MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
+ MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
+ MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
+ MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
+ MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
+ MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
+ MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
+ MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
+ MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
+ MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
+ MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
+ MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
+ MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
+ MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
+ MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
+
+ MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
+ MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
+ MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
+ MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
+ MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
+ MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
+ MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
+ MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
+ MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
+ MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
+ MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
+ MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
+ MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
+ MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
+ MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
+ MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
+
+ buf[0] += a;
+ buf[1] += b;
+ buf[2] += c;
+ buf[3] += d;
+}
+
+
+void MD5(void *dest, void *orig, int len)
+{
+ struct xMD5Context context;
+
+ xMD5Init(&context);
+ xMD5Update(&context, orig, len);
+ xMD5Final(dest, &context);
+}
+
+void secure_nick(char *result, char *user, char *host, char *key, int time)
+{
+ int k;
+ char *s, *t;
+ char *code = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
+ char src[SECURE_BUFFER_SIZE], dst[16];
+
+ sprintf(src, "%s%s%s%d", user, host, key, time);
+ MD5(dst, src, strlen(src));
+
+ s = dst; t = result;
+ for(k=0; k<NICK_LENGTH; k++) *t++ = code[((unsigned int) *s++)%52];
+ *t = '\0';
+
+ cout<<"RESULT=>"<<result
+ <<"< USER=>"<<user
+ <<"< HOST=>"<<host
+ <<"< KEY=>"<<key
+ <<"< time="<<time<<"\n";
+
+};