[CIFS] Replace cifs md5 hashing functions with kernel crypto APIs

Replace remaining use of md5 hash functions local to cifs module
with kernel crypto APIs.
Remove header and source file containing those local functions.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

6 files changed, 51 insertions, 416 deletions

diff --git a/fs/cifs/Makefile b/fs/cifs/Makefile
index 43b19dd..e132229 100644
--- a/fs/cifs/Makefile
+++ b/fs/cifs/Makefile
@@ -5,7 +5,7 @@ obj-$(CONFIG_CIFS) += cifs.o
 
 cifs-y := cifsfs.o cifssmb.o cifs_debug.o connect.o dir.o file.o inode.o \
 	  link.o misc.o netmisc.o smbdes.o smbencrypt.o transport.o asn1.o \
-	  md4.o md5.o cifs_unicode.o nterr.o xattr.o cifsencrypt.o \
+	  md4.o cifs_unicode.o nterr.o xattr.o cifsencrypt.o \
 	  readdir.o ioctl.o sess.o export.o
 
 cifs-$(CONFIG_CIFS_ACL) += cifsacl.o
diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index 66f3d50..35bf329 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -24,7 +24,6 @@
 #include "cifspdu.h"
 #include "cifsglob.h"
 #include "cifs_debug.h"
-#include "md5.h"
 #include "cifs_unicode.h"
 #include "cifsproto.h"
 #include "ntlmssp.h"
diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index 306769d..d3444ea 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -28,7 +28,6 @@
 #include "cifsproto.h"
 #include "cifs_debug.h"
 #include "cifs_fs_sb.h"
-#include "md5.h"
 
 #define CIFS_MF_SYMLINK_LEN_OFFSET (4+1)
 #define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1))
@@ -47,6 +46,45 @@
 	md5_hash[12], md5_hash[13], md5_hash[14], md5_hash[15]
 
 static int
+symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
+{
+	int rc;
+	unsigned int size;
+	struct crypto_shash *md5;
+	struct sdesc *sdescmd5;
+
+	md5 = crypto_alloc_shash("md5", 0, 0);
+	if (!md5 || IS_ERR(md5)) {
+		rc = PTR_ERR(md5);
+		cERROR(1, "%s: Crypto md5 allocation error %d\n", __func__, rc);
+		return rc;
+	}
+	size = sizeof(struct shash_desc) + crypto_shash_descsize(md5);
+	sdescmd5 = kmalloc(size, GFP_KERNEL);
+	if (!sdescmd5) {
+		rc = -ENOMEM;
+		cERROR(1, "%s: Memory allocation failure\n", __func__);
+		goto symlink_hash_err;
+	}
+	sdescmd5->shash.tfm = md5;
+	sdescmd5->shash.flags = 0x0;
+
+	rc = crypto_shash_init(&sdescmd5->shash);
+	if (rc) {
+		cERROR(1, "%s: Could not init md5 shash\n", __func__);
+		goto symlink_hash_err;
+	}
+	crypto_shash_update(&sdescmd5->shash, link_str, link_len);
+	rc = crypto_shash_final(&sdescmd5->shash, md5_hash);
+
+symlink_hash_err:
+	crypto_free_shash(md5);
+	kfree(sdescmd5);
+
+	return rc;
+}
+
+static int
 CIFSParseMFSymlink(const u8 *buf,
 		   unsigned int buf_len,
 		   unsigned int *_link_len,
@@ -56,7 +94,6 @@ CIFSParseMFSymlink(const u8 *buf,
 	unsigned int link_len;
 	const char *md5_str1;
 	const char *link_str;
-	struct MD5Context md5_ctx;
 	u8 md5_hash[16];
 	char md5_str2[34];
 
@@ -70,9 +107,11 @@ CIFSParseMFSymlink(const u8 *buf,
 	if (rc != 1)
 		return -EINVAL;
 
-	cifs_MD5_init(&md5_ctx);
-	cifs_MD5_update(&md5_ctx, (const u8 *)link_str, link_len);
-	cifs_MD5_final(md5_hash, &md5_ctx);
+	rc = symlink_hash(link_len, link_str, md5_hash);
+	if (rc) {
+		cFYI(1, "%s: MD5 hash failure: %d\n", __func__, rc);
+		return rc;
+	}
 
 	snprintf(md5_str2, sizeof(md5_str2),
 		 CIFS_MF_SYMLINK_MD5_FORMAT,
@@ -94,9 +133,9 @@ CIFSParseMFSymlink(const u8 *buf,
 static int
 CIFSFormatMFSymlink(u8 *buf, unsigned int buf_len, const char *link_str)
 {
+	int rc;
 	unsigned int link_len;
 	unsigned int ofs;
-	struct MD5Context md5_ctx;
 	u8 md5_hash[16];
 
 	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
@@ -107,9 +146,11 @@ CIFSFormatMFSymlink(u8 *buf, unsigned int buf_len, const char *link_str)
 	if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
 		return -ENAMETOOLONG;
 
-	cifs_MD5_init(&md5_ctx);
-	cifs_MD5_update(&md5_ctx, (const u8 *)link_str, link_len);
-	cifs_MD5_final(md5_hash, &md5_ctx);
+	rc = symlink_hash(link_len, link_str, md5_hash);
+	if (rc) {
+		cFYI(1, "%s: MD5 hash failure: %d\n", __func__, rc);
+		return rc;
+	}
 
 	snprintf(buf, buf_len,
 		 CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT,
diff --git a/fs/cifs/md5.c b/fs/cifs/md5.c
deleted file mode 100644
index 98b66a5..0000000
--- a/fs/cifs/md5.c
+++ /dev/null
@@ -1,366 +0,0 @@
-/*
- * 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 cifs_MD5_init, call cifs_MD5_update as
- * needed on buffers full of bytes, and then call cifs_MD5_final, which
- * will fill a supplied 16-byte array with the digest.
- */
-
-/* This code slightly modified to fit into Samba by
-   abartlet@samba.org Jun 2001
-   and to fit the cifs vfs by
-   Steve French sfrench@us.ibm.com */
-
-#include <linux/string.h>
-#include "md5.h"
-
-static void MD5Transform(__u32 buf[4], __u32 const in[16]);
-
-/*
- * Note: this code is harmless on little-endian machines.
- */
-static void
-byteReverse(unsigned char *buf, unsigned longs)
-{
-	__u32 t;
-	do {
-		t = (__u32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
-		    ((unsigned) buf[1] << 8 | buf[0]);
-		*(__u32 *) buf = t;
-		buf += 4;
-	} while (--longs);
-}
-
-/*
- * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
- * initialization constants.
- */
-void
-cifs_MD5_init(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
-cifs_MD5_update(struct MD5Context *ctx, unsigned char const *buf, unsigned len)
-{
-	register __u32 t;
-
-	/* Update bitcount */
-
-	t = ctx->bits[0];
-	if ((ctx->bits[0] = t + ((__u32) 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) {
-			memmove(p, buf, len);
-			return;
-		}
-		memmove(p, buf, t);
-		byteReverse(ctx->in, 16);
-		MD5Transform(ctx->buf, (__u32 *) ctx->in);
-		buf += t;
-		len -= t;
-	}
-	/* Process data in 64-byte chunks */
-
-	while (len >= 64) {
-		memmove(ctx->in, buf, 64);
-		byteReverse(ctx->in, 16);
-		MD5Transform(ctx->buf, (__u32 *) ctx->in);
-		buf += 64;
-		len -= 64;
-	}
-
-	/* Handle any remaining bytes of data. */
-
-	memmove(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
-cifs_MD5_final(unsigned char digest[16], struct MD5Context *ctx)
-{
-	unsigned int 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, (__u32 *) 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 */
-	((__u32 *) ctx->in)[14] = ctx->bits[0];
-	((__u32 *) ctx->in)[15] = ctx->bits[1];
-
-	MD5Transform(ctx->buf, (__u32 *) ctx->in);
-	byteReverse((unsigned char *) ctx->buf, 4);
-	memmove(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.  cifs_MD5_update blocks
- * the data and converts bytes into longwords for this routine.
- */
-static void
-MD5Transform(__u32 buf[4], __u32 const in[16])
-{
-	register __u32 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;
-}
-
-#if 0   /* currently unused */
-/***********************************************************************
- the rfc 2104 version of hmac_md5 initialisation.
-***********************************************************************/
-static void
-hmac_md5_init_rfc2104(unsigned char *key, int key_len,
-		      struct HMACMD5Context *ctx)
-{
-	int i;
-
-	/* if key is longer than 64 bytes reset it to key=MD5(key) */
-	if (key_len > 64) {
-		unsigned char tk[16];
-		struct MD5Context tctx;
-
-		cifs_MD5_init(&tctx);
-		cifs_MD5_update(&tctx, key, key_len);
-		cifs_MD5_final(tk, &tctx);
-
-		key = tk;
-		key_len = 16;
-	}
-
-	/* start out by storing key in pads */
-	memset(ctx->k_ipad, 0, sizeof(ctx->k_ipad));
-	memset(ctx->k_opad, 0, sizeof(ctx->k_opad));
-	memcpy(ctx->k_ipad, key, key_len);
-	memcpy(ctx->k_opad, key, key_len);
-
-	/* XOR key with ipad and opad values */
-	for (i = 0; i < 64; i++) {
-		ctx->k_ipad[i] ^= 0x36;
-		ctx->k_opad[i] ^= 0x5c;
-	}
-
-	cifs_MD5_init(&ctx->ctx);
-	cifs_MD5_update(&ctx->ctx, ctx->k_ipad, 64);
-}
-#endif
-
-/***********************************************************************
- the microsoft version of hmac_md5 initialisation.
-***********************************************************************/
-void
-hmac_md5_init_limK_to_64(const unsigned char *key, int key_len,
-			 struct HMACMD5Context *ctx)
-{
-	int i;
-
-	/* if key is longer than 64 bytes truncate it */
-	if (key_len > 64)
-		key_len = 64;
-
-	/* start out by storing key in pads */
-	memset(ctx->k_ipad, 0, sizeof(ctx->k_ipad));
-	memset(ctx->k_opad, 0, sizeof(ctx->k_opad));
-	memcpy(ctx->k_ipad, key, key_len);
-	memcpy(ctx->k_opad, key, key_len);
-
-	/* XOR key with ipad and opad values */
-	for (i = 0; i < 64; i++) {
-		ctx->k_ipad[i] ^= 0x36;
-		ctx->k_opad[i] ^= 0x5c;
-	}
-
-	cifs_MD5_init(&ctx->ctx);
-	cifs_MD5_update(&ctx->ctx, ctx->k_ipad, 64);
-}
-
-/***********************************************************************
- update hmac_md5 "inner" buffer
-***********************************************************************/
-void
-hmac_md5_update(const unsigned char *text, int text_len,
-		struct HMACMD5Context *ctx)
-{
-	cifs_MD5_update(&ctx->ctx, text, text_len);	/* then text of datagram */
-}
-
-/***********************************************************************
- finish off hmac_md5 "inner" buffer and generate outer one.
-***********************************************************************/
-void
-hmac_md5_final(unsigned char *digest, struct HMACMD5Context *ctx)
-{
-	struct MD5Context ctx_o;
-
-	cifs_MD5_final(digest, &ctx->ctx);
-
-	cifs_MD5_init(&ctx_o);
-	cifs_MD5_update(&ctx_o, ctx->k_opad, 64);
-	cifs_MD5_update(&ctx_o, digest, 16);
-	cifs_MD5_final(digest, &ctx_o);
-}
-
-/***********************************************************
- single function to calculate an HMAC MD5 digest from data.
- use the microsoft hmacmd5 init method because the key is 16 bytes.
-************************************************************/
-#if 0 /* currently unused */
-static void
-hmac_md5(unsigned char key[16], unsigned char *data, int data_len,
-	 unsigned char *digest)
-{
-	struct HMACMD5Context ctx;
-	hmac_md5_init_limK_to_64(key, 16, &ctx);
-	if (data_len != 0)
-		hmac_md5_update(data, data_len, &ctx);
-
-	hmac_md5_final(digest, &ctx);
-}
-#endif
diff --git a/fs/cifs/md5.h b/fs/cifs/md5.h
deleted file mode 100644
index 6fba8cb..0000000
--- a/fs/cifs/md5.h
+++ /dev/null
@@ -1,38 +0,0 @@
-#ifndef MD5_H
-#define MD5_H
-#ifndef HEADER_MD5_H
-/* Try to avoid clashes with OpenSSL */
-#define HEADER_MD5_H
-#endif
-
-struct MD5Context {
-	__u32 buf[4];
-	__u32 bits[2];
-	unsigned char in[64];
-};
-#endif				/* !MD5_H */
-
-#ifndef _HMAC_MD5_H
-struct HMACMD5Context {
-	struct MD5Context ctx;
-	unsigned char k_ipad[65];
-	unsigned char k_opad[65];
-};
-#endif				/* _HMAC_MD5_H */
-
-void cifs_MD5_init(struct MD5Context *context);
-void cifs_MD5_update(struct MD5Context *context, unsigned char const *buf,
-			unsigned len);
-void cifs_MD5_final(unsigned char digest[16], struct MD5Context *context);
-
-/* The following definitions come from lib/hmacmd5.c  */
-
-/* void hmac_md5_init_rfc2104(unsigned char *key, int key_len,
-			struct HMACMD5Context *ctx);*/
-void hmac_md5_init_limK_to_64(const unsigned char *key, int key_len,
-			struct HMACMD5Context *ctx);
-void hmac_md5_update(const unsigned char *text, int text_len,
-			struct HMACMD5Context *ctx);
-void hmac_md5_final(unsigned char *digest, struct HMACMD5Context *ctx);
-/* void hmac_md5(unsigned char key[16], unsigned char *data, int data_len,
-			unsigned char *digest);*/
diff --git a/fs/cifs/smbencrypt.c b/fs/cifs/smbencrypt.c
index 192ea51..3013500 100644
--- a/fs/cifs/smbencrypt.c
+++ b/fs/cifs/smbencrypt.c
@@ -32,7 +32,6 @@
 #include "cifs_unicode.h"
 #include "cifspdu.h"
 #include "cifsglob.h"
-#include "md5.h"
 #include "cifs_debug.h"
 #include "cifsencrypt.h"