Skip to main content

Browse the archive

Revision 2cfb8ce8c87802181ade74f5dadb3dded9bb4c7e authored by Jan Nikitenko on 13 March 2008, 19:32:39 UTC, committed by Linus Torvalds on 13 March 2008, 20:11:43 UTC 
spi_bitbang: short transfer status fix
 
SPI controller drivers return number of bytes actually transfered from
bitbang->txrx_bufs() method.  This updates handling of short transfers (where
the transfer size is less than requested):

 - Even zero byte short transfers should report errors;
 - Include short transfers in the total of transferred bytes;
 - Use EREMOTEIO (like USB) not EMSGSIZE to report short transfers

Short transfers don't normally mean invalid message sizes, but if the
underlying controller driver needs to use EMSGSIZE it can still do so.

[db: fix two more minor issues]
Signed-off-by: Jan Nikitenko <jan.nikitenko@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 40369e1
Raw File
sha1.c 
/*
 * SHA transform algorithm, originally taken from code written by
 * Peter Gutmann, and placed in the public domain.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/cryptohash.h>

/* The SHA f()-functions.  */

#define f1(x,y,z)   (z ^ (x & (y ^ z)))		/* x ? y : z */
#define f2(x,y,z)   (x ^ y ^ z)			/* XOR */
#define f3(x,y,z)   ((x & y) + (z & (x ^ y)))	/* majority */

/* The SHA Mysterious Constants */

#define K1  0x5A827999L			/* Rounds  0-19: sqrt(2) * 2^30 */
#define K2  0x6ED9EBA1L			/* Rounds 20-39: sqrt(3) * 2^30 */
#define K3  0x8F1BBCDCL			/* Rounds 40-59: sqrt(5) * 2^30 */
#define K4  0xCA62C1D6L			/* Rounds 60-79: sqrt(10) * 2^30 */

/**
 * sha_transform - single block SHA1 transform
 *
 * @digest: 160 bit digest to update
 * @data:   512 bits of data to hash
 * @W:      80 words of workspace (see note)
 *
 * This function generates a SHA1 digest for a single 512-bit block.
 * Be warned, it does not handle padding and message digest, do not
 * confuse it with the full FIPS 180-1 digest algorithm for variable
 * length messages.
 *
 * Note: If the hash is security sensitive, the caller should be sure
 * to clear the workspace. This is left to the caller to avoid
 * unnecessary clears between chained hashing operations.
 */
void sha_transform(__u32 *digest, const char *in, __u32 *W)
{
	__u32 a, b, c, d, e, t, i;

	for (i = 0; i < 16; i++)
		W[i] = be32_to_cpu(((const __be32 *)in)[i]);

	for (i = 0; i < 64; i++)
		W[i+16] = rol32(W[i+13] ^ W[i+8] ^ W[i+2] ^ W[i], 1);

	a = digest[0];
	b = digest[1];
	c = digest[2];
	d = digest[3];
	e = digest[4];

	for (i = 0; i < 20; i++) {
		t = f1(b, c, d) + K1 + rol32(a, 5) + e + W[i];
		e = d; d = c; c = rol32(b, 30); b = a; a = t;
	}

	for (; i < 40; i ++) {
		t = f2(b, c, d) + K2 + rol32(a, 5) + e + W[i];
		e = d; d = c; c = rol32(b, 30); b = a; a = t;
	}

	for (; i < 60; i ++) {
		t = f3(b, c, d) + K3 + rol32(a, 5) + e + W[i];
		e = d; d = c; c = rol32(b, 30); b = a; a = t;
	}

	for (; i < 80; i ++) {
		t = f2(b, c, d) + K4 + rol32(a, 5) + e + W[i];
		e = d; d = c; c = rol32(b, 30); b = a; a = t;
	}

	digest[0] += a;
	digest[1] += b;
	digest[2] += c;
	digest[3] += d;
	digest[4] += e;
}
EXPORT_SYMBOL(sha_transform);

/**
 * sha_init - initialize the vectors for a SHA1 digest
 * @buf: vector to initialize
 */
void sha_init(__u32 *buf)
{
	buf[0] = 0x67452301;
	buf[1] = 0xefcdab89;
	buf[2] = 0x98badcfe;
	buf[3] = 0x10325476;
	buf[4] = 0xc3d2e1f0;
}
back to top