cifs: More crypto cleanup (try #2)

Replaced md4 hashing function local to cifs module with kernel crypto APIs.
As a result, md4 hashing function and its supporting functions in
file md4.c are not needed anymore.

Cleaned up function declarations, removed forward function declarations,
and removed a header file that is being deleted from being included.

Verified that sec=ntlm/i, sec=ntlmv2/i, and sec=ntlmssp/i work correctly.

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

1 files changed, 64 insertions, 26 deletions

diff --git a/fs/cifs/smbencrypt.c b/fs/cifs/smbencrypt.c
index 30135005e4f3..b5450e9f40c0 100644
--- a/fs/cifs/smbencrypt.c
+++ b/fs/cifs/smbencrypt.c
@@ -33,7 +33,7 @@
 #include "cifspdu.h"
 #include "cifsglob.h"
 #include "cifs_debug.h"
-#include "cifsencrypt.h"
+#include "cifsproto.h"
 
 #ifndef false
 #define false 0
@@ -47,14 +47,57 @@
 #define SSVALX(buf,pos,val) (CVAL(buf,pos)=(val)&0xFF,CVAL(buf,pos+1)=(val)>>8)
 #define SSVAL(buf,pos,val) SSVALX((buf),(pos),((__u16)(val)))
 
-/*The following definitions come from  libsmb/smbencrypt.c  */
+/* produce a md4 message digest from data of length n bytes */
+int
+mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
+{
+        int rc;
+        unsigned int size;
+        struct crypto_shash *md4;
+        struct sdesc *sdescmd4;
+
+        md4 = crypto_alloc_shash("md4", 0, 0);
+        if (IS_ERR(md4)) {
+                cERROR(1, "%s: Crypto md4 allocation error %d\n", __func__, rc);
+                return PTR_ERR(md4);
+        }
+        size = sizeof(struct shash_desc) + crypto_shash_descsize(md4);
+        sdescmd4 = kmalloc(size, GFP_KERNEL);
+        if (!sdescmd4) {
+                rc = -ENOMEM;
+                cERROR(1, "%s: Memory allocation failure\n", __func__);
+                goto mdfour_err;
+        }
+        sdescmd4->shash.tfm = md4;
+        sdescmd4->shash.flags = 0x0;
+
+        rc = crypto_shash_init(&sdescmd4->shash);
+        if (rc) {
+                cERROR(1, "%s: Could not init md4 shash\n", __func__);
+                goto mdfour_err;
+        }
+        crypto_shash_update(&sdescmd4->shash, link_str, link_len);
+        rc = crypto_shash_final(&sdescmd4->shash, md4_hash);
 
-void SMBencrypt(unsigned char *passwd, const unsigned char *c8,
-                unsigned char *p24);
-void E_md4hash(const unsigned char *passwd, unsigned char *p16);
-static void SMBOWFencrypt(unsigned char passwd[16], const unsigned char *c8,
-                   unsigned char p24[24]);
-void SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24);
+mdfour_err:
+        crypto_free_shash(md4);
+        kfree(sdescmd4);
+
+        return rc;
+}
+
+/* Does the des encryption from the NT or LM MD4 hash. */
+static void
+SMBOWFencrypt(unsigned char passwd[16], const unsigned char *c8,
+              unsigned char p24[24])
+{
+        unsigned char p21[21];
+
+        memset(p21, '\0', 21);
+
+        memcpy(p21, passwd, 16);
+        E_P24(p21, c8, p24);
+}
 
 /*
    This implements the X/Open SMB password encryption
@@ -117,9 +160,10 @@ _my_mbstowcs(__u16 *dst, const unsigned char *src, int len)
  * Creates the MD4 Hash of the users password in NT UNICODE.
  */
 
-void
+int
 E_md4hash(const unsigned char *passwd, unsigned char *p16)
 {
+        int rc;
         int len;
         __u16 wpwd[129];
 
@@ -138,8 +182,10 @@ E_md4hash(const unsigned char *passwd, unsigned char *p16)
         /* Calculate length in bytes */
         len = _my_wcslen(wpwd) * sizeof(__u16);
 
-        mdfour(p16, (unsigned char *) wpwd, len);
+        rc = mdfour(p16, (unsigned char *) wpwd, len);
         memset(wpwd, 0, 129 * 2);
+
+        return rc;
 }
 
 #if 0 /* currently unused */
@@ -211,19 +257,6 @@ ntv2_owf_gen(const unsigned char owf[16], const char *user_n,
 }
 #endif
 
-/* Does the des encryption from the NT or LM MD4 hash. */
-static void
-SMBOWFencrypt(unsigned char passwd[16], const unsigned char *c8,
-              unsigned char p24[24])
-{
-        unsigned char p21[21];
-
-        memset(p21, '\0', 21);
-
-        memcpy(p21, passwd, 16);
-        E_P24(p21, c8, p24);
-}
-
 /* Does the des encryption from the FIRST 8 BYTES of the NT or LM MD4 hash. */
 #if 0 /* currently unused */
 static void
@@ -241,16 +274,21 @@ NTLMSSPOWFencrypt(unsigned char passwd[8],
 #endif
 
 /* Does the NT MD4 hash then des encryption. */
-
-void
+int
 SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24)
 {
+        int rc;
         unsigned char p21[21];
 
         memset(p21, '\0', 21);
 
-        E_md4hash(passwd, p21);
+        rc = E_md4hash(passwd, p21);
+        if (rc) {
+                cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
+                return rc;
+        }
         SMBOWFencrypt(p21, c8, p24);
+        return rc;
 }