[Toybox] [PATCH 4/8] Add new toy - md5sum

Georgi Chorbadzhiyski gf at unixsol.org
Tue Apr 24 02:20:47 PDT 2012


---
 toys/md5sum.c |  273 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 273 insertions(+), 0 deletions(-)
 create mode 100644 toys/md5sum.c

diff --git a/toys/md5sum.c b/toys/md5sum.c
new file mode 100644
index 0000000..1162c05
--- /dev/null
+++ b/toys/md5sum.c
@@ -0,0 +1,273 @@
+/* vi: set sw=4 ts=4:
+ *
+ * md5sum.c - Calculate md5 cryptographic hash for input.
+ *
+ * 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.
+ *
+ * Not in SUSv3.
+
+USE_MD5SUM(NEWTOY(md5sum, NULL, TOYFLAG_USR|TOYFLAG_BIN))
+
+config MD5SUM
+	bool "md5sum"
+	default y
+	help
+	  usage: md5sum [file...]
+
+	  Calculate md5 hash of files (or stdin).
+*/
+
+#include <toys.h>
+
+static void byteReverse(unsigned char *buf, unsigned longs)
+{
+#ifdef IS_BIG_ENDIAN
+	uint32_t t;
+	do {
+		t = (uint32_t) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
+			((unsigned) buf[1] << 8 | buf[0]);
+		*(uint32_t *) buf = t;
+		buf += 4;
+	} while (--longs);
+#endif
+}
+
+struct md5 {
+	uint32_t buf[4];
+	uint32_t bits[2];
+	unsigned char in[64];
+};
+
+/*
+ * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
+ * initialization constants.
+ */
+static void md5_init(struct md5 *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;
+}
+
+/* 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.  md5_update blocks
+ * the data and converts bytes into longwords for this routine.
+ */
+static void md5_transform(uint32_t buf[4], uint32_t in[16])
+{
+	uint32_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;
+}
+
+/*
+ * Update context to reflect the concatenation of another buffer full
+ * of bytes.
+ */
+static void md5_update(struct md5 *ctx, unsigned char *buf, unsigned len)
+{
+	uint32_t t;
+
+	/* Update bitcount */
+
+	t = ctx->bits[0];
+	if ((ctx->bits[0] = t + ((uint32_t) len << 3)) < t)
+		ctx->bits[1]++; /* Carry from low to high */
+
+	ctx->bits[1] += len >> 29;
+
+	t = (t >> 3) & 0x3f;
+
+	/* 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);
+		md5_transform(ctx->buf, (uint32_t *) ctx->in);
+		buf += t;
+		len -= t;
+	}
+
+	/* Process data in 64-byte chunks */
+	while (len >= 64) {
+		memcpy(ctx->in, buf, 64);
+		byteReverse(ctx->in, 16);
+		md5_transform(ctx->buf, (uint32_t *) 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)
+ */
+static void md5_final(struct md5 *ctx, unsigned char digest[16])
+{
+	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);
+		md5_transform(ctx->buf, (uint32_t *) 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_t *c = (uint32_t *)ctx->in;
+	c[14] = ctx->bits[0];
+	c[15] = ctx->bits[1];
+
+	md5_transform(ctx->buf, (uint32_t *) ctx->in);
+	byteReverse((unsigned char *) ctx->buf, 4);
+	memcpy(digest, ctx->buf, 16);
+	memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */
+}
+
+static void do_md5(int fd, char *name)
+{
+	struct md5 this;
+	int len;
+
+	md5_init(&this);
+	for (;;) {
+		len = read(fd, toybuf, sizeof(toybuf));
+		if (len < 1)
+			break;
+		md5_update(&this, (unsigned char *)toybuf, len);
+	}
+	md5_final(&this, (unsigned char *)toybuf);
+	for (len = 0; len < 16; len++) printf("%02x", toybuf[len]);
+	printf("  %s\n", name);
+}
+
+void md5sum_main(void)
+{
+	loopfiles(toys.optargs, do_md5);
+}
-- 
1.7.5.1


 1335259247.0


More information about the Toybox mailing list