--- /dev/null
+/* $OpenBSD: md5.c,v 1.1 1996/04/17 05:03:08 mickey Exp $ */
+
+/*
+ * Copyright (c) 1996 Michael Shalayeff.
+ *
+ * This software derived from one contributed by Theodore Ts'o.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by Theodore Ts'o.
+ * 4. Neither the name of the University nor of the Laboratory may be used
+ * to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+/*
+ * The code for MD5 transform was taken from Colin Plumb's
+ * implementation, which has been placed in the public domain. The
+ * MD5 cryptographic checksum was devised by Ronald Rivest, and is
+ * documented in RFC 1321, "The MD5 Message Digest Algorithm".
+ *
+ */
+
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/kernel.h>
+
+/*
+ * MD5 transform algorithm, taken from code written by Colin Plumb,
+ * and put into the public domain
+ *
+ * QUESTION: Replace this with SHA, which as generally received better
+ * reviews from the cryptographic community?
+ */
+void
+MD5Init(buf)
+ u_int32_t buf[4];
+{
+ buf[0] = 0x67452301;
+ buf[1] = 0xefcdab89;
+ buf[2] = 0x98badcfe;
+ buf[3] = 0x10325476;
+}
+
+/* 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(buf, in)
+ u_int32_t buf[4];
+ u_int32_t const in[16];
+{
+ u_int32_t 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;
+}
+