--- /dev/null
+/* mcookie.c -- Generates random numbers for xauth
+ * Created: Fri Feb 3 10:42:48 1995 by faith@cs.unc.edu
+ * Revised: Fri Mar 19 07:48:01 1999 by faith@acm.org
+ * Public Domain 1995, 1999 Rickard E. Faith (faith@acm.org)
+ * This program comes with ABSOLUTELY NO WARRANTY.
+ *
+ * $Id: mcookie.c,v 1.5 1997/07/06 00:13:06 aebr Exp $
+ *
+ * This program gathers some random bits of data and used the MD5
+ * message-digest algorithm to generate a 128-bit hexadecimal number for
+ * use with xauth(1).
+ *
+ * NOTE: Unless /dev/random is available, this program does not actually
+ * gather 128 bits of random information, so the magic cookie generated
+ * will be considerably easier to guess than one might expect.
+ *
+ * 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@pld.ORG.PL>
+ * - added Native Language Support
+ * 1999-03-21 aeb: Added some fragments of code from Colin Plumb.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <sys/time.h>
+#include <time.h>
+#include <unistd.h>
+
+#define BUFFERSIZE 4096
+
+
+#ifndef MD5_H
+#define MD5_H
+
+#if defined (__alpha__) || defined (__ia64__) || defined (__x86_64__)
+typedef unsigned int uint32;
+#else
+typedef unsigned long uint32;
+#endif
+
+struct MD5Context {
+ uint32 buf[4];
+ uint32 bits[2];
+ unsigned char in[64];
+};
+
+void MD5Init(struct MD5Context *context);
+void MD5Update(struct MD5Context *context, unsigned char const *buf,
+ unsigned len);
+void MD5Final(unsigned char digest[16], struct MD5Context *context);
+void MD5Transform(uint32 buf[4], uint32 const in[16]);
+
+/*
+ * This is needed to make RSAREF happy on some MS-DOS compilers.
+ */
+typedef struct MD5Context MD5_CTX;
+
+#endif /* !MD5_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.
+ */
+#include <string.h> /* for memcpy() */
+#include <endian.h>
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+#define byteReverse(buf, len) /* Nothing */
+#else
+void byteReverse(unsigned char *buf, unsigned longs);
+
+/*
+ * Note: this code is harmless on little-endian machines.
+ */
+void byteReverse(unsigned char *buf, unsigned longs)
+{
+ uint32 t;
+ do {
+ t = (uint32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
+ ((unsigned) buf[1] << 8 | buf[0]);
+ *(uint32 *) buf = t;
+ buf += 4;
+ } while (--longs);
+}
+#endif
+
+/*
+ * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
+ * initialization constants.
+ */
+void MD5Init(struct MD5Context *ctx)
+{
+ ctx->buf[0] = 0x67452301;
+ ctx->buf[1] = 0xefcdab89;
+ ctx->buf[2] = 0x98badcfe;
+ ctx->buf[3] = 0x10325476;
+
+ ctx->bits[0] = 0;
+ ctx->bits[1] = 0;
+}
+
+/*
+ * Update context to reflect the concatenation of another buffer full
+ * of bytes.
+ */
+void MD5Update(struct MD5Context *ctx, unsigned char const *buf, unsigned len)
+{
+ uint32 t;
+
+ /* Update bitcount */
+
+ t = ctx->bits[0];
+ if ((ctx->bits[0] = t + ((uint32) len << 3)) < t)
+ ctx->bits[1]++; /* Carry from low to high */
+ ctx->bits[1] += len >> 29;
+
+ t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
+
+ /* Handle any leading odd-sized chunks */
+
+ if (t) {
+ unsigned char *p = (unsigned char *) ctx->in + t;
+
+ t = 64 - t;
+ if (len < t) {
+ memcpy(p, buf, len);
+ return;
+ }
+ memcpy(p, buf, t);
+ byteReverse(ctx->in, 16);
+ MD5Transform(ctx->buf, (uint32 *) ctx->in);
+ buf += t;
+ len -= t;
+ }
+ /* Process data in 64-byte chunks */
+
+ while (len >= 64) {
+ memcpy(ctx->in, buf, 64);
+ byteReverse(ctx->in, 16);
+ MD5Transform(ctx->buf, (uint32 *) ctx->in);
+ buf += 64;
+ len -= 64;
+ }
+
+ /* Handle any remaining bytes of data. */
+
+ memcpy(ctx->in, buf, len);
+}
+
+/*
+ * Final wrapup - pad to 64-byte boundary with the bit pattern
+ * 1 0* (64-bit count of bits processed, MSB-first)
+ */
+void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
+{
+ unsigned count;
+ unsigned char *p;
+
+ /* Compute number of bytes mod 64 */
+ count = (ctx->bits[0] >> 3) & 0x3F;
+
+ /* Set the first char of padding to 0x80. This is safe since there is
+ always at least one byte free */
+ p = ctx->in + count;
+ *p++ = 0x80;
+
+ /* Bytes of padding needed to make 64 bytes */
+ count = 64 - 1 - count;
+
+ /* Pad out to 56 mod 64 */
+ if (count < 8) {
+ /* Two lots of padding: Pad the first block to 64 bytes */
+ memset(p, 0, count);
+ byteReverse(ctx->in, 16);
+ MD5Transform(ctx->buf, (uint32 *) ctx->in);
+
+ /* Now fill the next block with 56 bytes */
+ memset(ctx->in, 0, 56);
+ } else {
+ /* Pad block to 56 bytes */
+ memset(p, 0, count - 8);
+ }
+ byteReverse(ctx->in, 14);
+
+ /* Append length in bits and transform */
+ ((uint32 *) ctx->in)[14] = ctx->bits[0];
+ ((uint32 *) ctx->in)[15] = ctx->bits[1];
+
+ MD5Transform(ctx->buf, (uint32 *) ctx->in);
+ byteReverse((unsigned char *) ctx->buf, 4);
+ memcpy(digest, ctx->buf, 16);
+ memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */
+}
+
+/* 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, data, s) \
+ ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += 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 MD5Transform(uint32 buf[4], uint32 const in[16])
+{
+ register uint32 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;
+}
+
+
+
+
+struct rngs {
+ const char *path;
+ int minlength, maxlength;
+} rngs[] = {
+ { "/dev/random", 16, 16 }, /* 16 bytes = 128 bits suffice */
+ { "/proc/interrupts", 0, 0 },
+ { "/proc/slabinfo", 0, 0 },
+ { "/proc/stat", 0, 0 },
+ { "/dev/urandom", 32, 64 },
+};
+#define RNGS (sizeof(rngs)/sizeof(struct rngs))
+
+int Verbose = 0;
+
+/* The basic function to hash a file */
+static off_t
+hash_file(struct MD5Context *ctx, int fd)
+{
+ off_t count = 0;
+ ssize_t r;
+ unsigned char buf[BUFFERSIZE];
+
+ while ((r = read(fd, buf, sizeof(buf))) > 0) {
+ MD5Update(ctx, buf, r);
+ count += r;
+ }
+ /* Separate files with a null byte */
+ buf[0] = 0;
+ MD5Update(ctx, buf, 1);
+ return count;
+}
+
+int main( int argc, char **argv )
+{
+ int i;
+ struct MD5Context ctx;
+ unsigned char digest[16];
+ unsigned char buf[BUFFERSIZE];
+ int fd;
+ int c;
+ pid_t pid;
+ char *file = NULL;
+ int r;
+ struct timeval tv;
+ struct timezone tz;
+
+ while ((c = getopt( argc, argv, "vf:" )) != -1)
+ switch (c) {
+ case 'v': ++Verbose; break;
+ case 'f': file = optarg; break;
+ }
+
+ MD5Init( &ctx );
+
+ gettimeofday( &tv, &tz );
+ MD5Update( &ctx, (unsigned char *)&tv, sizeof( tv ) );
+ pid = getppid();
+ MD5Update( &ctx, (unsigned char *)&pid, sizeof( pid ));
+ pid = getpid();
+ MD5Update( &ctx, (unsigned char *)&pid, sizeof( pid ));
+
+ if (file) {
+ int count = 0;
+
+ if (file[0] == '-' && !file[1])
+ fd = fileno(stdin);
+ else
+ fd = open( file, O_RDONLY );
+
+ if (fd < 0) {
+ fprintf( stderr, "Could not open %s\n", file );
+ } else {
+ count = hash_file( &ctx, fd );
+ if (Verbose)
+ fprintf( stderr, "Got %d bytes from %s\n", count, file );
+
+ if (file[0] != '-' || file[1]) close( fd );
+ }
+ }
+
+ for (i = 0; i < RNGS; i++) {
+ if ((fd = open( rngs[i].path, O_RDONLY|O_NONBLOCK )) >= 0) {
+ int count = sizeof(buf);
+
+ if (rngs[i].maxlength && count > rngs[i].maxlength)
+ count = rngs[i].maxlength;
+ r = read( fd, buf, count );
+ if (r > 0)
+ MD5Update( &ctx, buf, r );
+ else
+ r = 0;
+ close( fd );
+ if (Verbose)
+ fprintf( stderr, "Got %d bytes from %s\n", r, rngs[i].path );
+ if (rngs[i].minlength && r >= rngs[i].minlength)
+ break;
+ } else if (Verbose)
+ fprintf( stderr, "Could not open %s\n", rngs[i].path );
+ }
+
+ MD5Final( digest, &ctx );
+ for (i = 0; i < 16; i++) printf( "%02x", digest[i] );
+ putchar ( '\n' );
+
+ /*
+ * The following is important for cases like disk full, so shell scripts
+ * can bomb out properly rather than think they succeeded.
+ */
+ if (fflush(stdout) < 0 || fclose(stdout) < 0)
+ return 1;
+
+ return 0;
+}