ima: provide support for arbitrary hash algorithms

In preparation of supporting more hash algorithms with larger hash sizes
needed for signature verification, this patch replaces the 20 byte sized
digest, with a more flexible structure.  The new structure includes the
hash algorithm, digest size, and digest.

Changelog:
- recalculate filedata hash for the measurement list, if the signature
  hash digest size is greater than 20 bytes.
- use generic HASH_ALGO_
- make ima_calc_file_hash static
- scripts lindent and checkpatch fixes

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

crypto/asymmetric_keys/x509_parser.h

@@ -21,8 +21,6 @@ struct x509_certificate {
 	char		*authority;		/* Authority key fingerprint as hex */
 	struct tm	valid_from;
 	struct tm	valid_to;
-	enum pkey_algo	pkey_algo : 8;		/* Public key algorithm */
-	enum hash_algo sig_hash_algo : 8;	/* Signature hash algorithm */
 	const void	*tbs;			/* Signed data */
 	unsigned	tbs_size;		/* Size of signed data */
 	unsigned	raw_sig_size;		/* Size of sigature */

crypto/asymmetric_keys/x509_public_key.c

@@ -213,7 +213,8 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
 		 cert->valid_to.tm_year + 1900, cert->valid_to.tm_mon + 1,
 		 cert->valid_to.tm_mday, cert->valid_to.tm_hour,
 		 cert->valid_to.tm_min,  cert->valid_to.tm_sec);
-	pr_devel("Cert Signature: %s\n",
+	pr_devel("Cert Signature: %s + %s\n",
+		 pkey_algo_name[cert->sig.pkey_algo],
 		 hash_algo_name[cert->sig.pkey_hash_algo]);
 
 	if (!cert->fingerprint) {