Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull security subsystem updates from James Morris:
 "In this patchset, we finally get an SELinux update, with Paul Moore
  taking over as maintainer of that code.

  Also a significant update for the Keys subsystem, as well as
  maintenance updates to Smack, IMA, TPM, and Apparmor"

and since I wanted to know more about the updates to key handling,
here's the explanation from David Howells on that:

 "Okay.  There are a number of separate bits.  I'll go over the big bits
  and the odd important other bit, most of the smaller bits are just
  fixes and cleanups.  If you want the small bits accounting for, I can
  do that too.

   (1) Keyring capacity expansion.

        KEYS: Consolidate the concept of an 'index key' for key access
        KEYS: Introduce a search context structure
        KEYS: Search for auth-key by name rather than target key ID
        Add a generic associative array implementation.
        KEYS: Expand the capacity of a keyring

     Several of the patches are providing an expansion of the capacity of a
     keyring.  Currently, the maximum size of a keyring payload is one page.
     Subtract a small header and then divide up into pointers, that only gives
     you ~500 pointers on an x86_64 box.  However, since the NFS idmapper uses
     a keyring to store ID mapping data, that has proven to be insufficient to
     the cause.

     Whatever data structure I use to handle the keyring payload, it can only
     store pointers to keys, not the keys themselves because several keyrings
     may point to a single key.  This precludes inserting, say, and rb_node
     struct into the key struct for this purpose.

     I could make an rbtree of records such that each record has an rb_node
     and a key pointer, but that would use four words of space per key stored
     in the keyring.  It would, however, be able to use much existing code.

     I selected instead a non-rebalancing radix-tree type approach as that
     could have a better space-used/key-pointer ratio.  I could have used the
     radix tree implementation that we already have and insert keys into it by
     their serial numbers, but that means any sort of search must iterate over
     the whole radix tree.  Further, its nodes are a bit on the capacious side
     for what I want - especially given that key serial numbers are randomly
     allocated, thus leaving a lot of empty space in the tree.

     So what I have is an associative array that internally is a radix-tree
     with 16 pointers per node where the index key is constructed from the key
     type pointer and the key description.  This means that an exact lookup by
     type+description is very fast as this tells us how to navigate directly to
     the target key.

     I made the data structure general in lib/assoc_array.c as far as it is
     concerned, its index key is just a sequence of bits that leads to a
     pointer.  It's possible that someone else will be able to make use of it
     also.  FS-Cache might, for example.

   (2) Mark keys as 'trusted' and keyrings as 'trusted only'.

        KEYS: verify a certificate is signed by a 'trusted' key
        KEYS: Make the system 'trusted' keyring viewable by userspace
        KEYS: Add a 'trusted' flag and a 'trusted only' flag
        KEYS: Separate the kernel signature checking keyring from module signing

     These patches allow keys carrying asymmetric public keys to be marked as
     being 'trusted' and allow keyrings to be marked as only permitting the
     addition or linkage of trusted keys.

     Keys loaded from hardware during kernel boot or compiled into the kernel
     during build are marked as being trusted automatically.  New keys can be
     loaded at runtime with add_key().  They are checked against the system
     keyring contents and if their signatures can be validated with keys that
     are already marked trusted, then they are marked trusted also and can
     thus be added into the master keyring.

     Patches from Mimi Zohar make this usable with the IMA keyrings also.

   (3) Remove the date checks on the key used to validate a module signature.

        X.509: Remove certificate date checks

     It's not reasonable to reject a signature just because the key that it was
     generated with is no longer valid datewise - especially if the kernel
     hasn't yet managed to set the system clock when the first module is
     loaded - so just remove those checks.

   (4) Make it simpler to deal with additional X.509 being loaded into the kernel.

        KEYS: Load *.x509 files into kernel keyring
        KEYS: Have make canonicalise the paths of the X.509 certs better to deduplicate

     The builder of the kernel now just places files with the extension ".x509"
     into the kernel source or build trees and they're concatenated by the
     kernel build and stuffed into the appropriate section.

   (5) Add support for userspace kerberos to use keyrings.

        KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches
        KEYS: Implement a big key type that can save to tmpfs

     Fedora went to, by default, storing kerberos tickets and tokens in tmpfs.
     We looked at storing it in keyrings instead as that confers certain
     advantages such as tickets being automatically deleted after a certain
     amount of time and the ability for the kernel to get at these tokens more
     easily.

     To make this work, two things were needed:

     (a) A way for the tickets to persist beyond the lifetime of all a user's
         sessions so that cron-driven processes can still use them.

         The problem is that a user's session keyrings are deleted when the
         session that spawned them logs out and the user's user keyring is
         deleted when the UID is deleted (typically when the last log out
         happens), so neither of these places is suitable.

         I've added a system keyring into which a 'persistent' keyring is
         created for each UID on request.  Each time a user requests their
         persistent keyring, the expiry time on it is set anew.  If the user
         doesn't ask for it for, say, three days, the keyring is automatically
         expired and garbage collected using the existing gc.  All the kerberos
         tokens it held are then also gc'd.

     (b) A key type that can hold really big tickets (up to 1MB in size).

         The problem is that Active Directory can return huge tickets with lots
         of auxiliary data attached.  We don't, however, want to eat up huge
         tracts of unswappable kernel space for this, so if the ticket is
         greater than a certain size, we create a swappable shmem file and dump
         the contents in there and just live with the fact we then have an
         inode and a dentry overhead.  If the ticket is smaller than that, we
         slap it in a kmalloc()'d buffer"

* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (121 commits)
  KEYS: Fix keyring content gc scanner
  KEYS: Fix error handling in big_key instantiation
  KEYS: Fix UID check in keyctl_get_persistent()
  KEYS: The RSA public key algorithm needs to select MPILIB
  ima: define '_ima' as a builtin 'trusted' keyring
  ima: extend the measurement list to include the file signature
  kernel/system_certificate.S: use real contents instead of macro GLOBAL()
  KEYS: fix error return code in big_key_instantiate()
  KEYS: Fix keyring quota misaccounting on key replacement and unlink
  KEYS: Fix a race between negating a key and reading the error set
  KEYS: Make BIG_KEYS boolean
  apparmor: remove the "task" arg from may_change_ptraced_domain()
  apparmor: remove parent task info from audit logging
  apparmor: remove tsk field from the apparmor_audit_struct
  apparmor: fix capability to not use the current task, during reporting
  Smack: Ptrace access check mode
  ima: provide hash algo info in the xattr
  ima: enable support for larger default filedata hash algorithms
  ima: define kernel parameter 'ima_template=' to change configured default
  ima: add Kconfig default measurement list template
  ...

11 files changed, 296 insertions, 140 deletions

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 71f337a..4ae5734 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1402,6 +1402,9 @@ config CRYPTO_USER_API_SKCIPHER
 	  This option enables the user-spaces interface for symmetric
 	  key cipher algorithms.
 
+config CRYPTO_HASH_INFO
+	bool
+
 source "drivers/crypto/Kconfig"
 source crypto/asymmetric_keys/Kconfig
 
diff --git a/crypto/Makefile b/crypto/Makefile
index 80019ba..b3a7e80 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -104,3 +104,4 @@ obj-$(CONFIG_CRYPTO_USER_API_SKCIPHER) += algif_skcipher.o
 obj-$(CONFIG_XOR_BLOCKS) += xor.o
 obj-$(CONFIG_ASYNC_CORE) += async_tx/
 obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys/
+obj-$(CONFIG_CRYPTO_HASH_INFO) += hash_info.o
diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig
index 6d2c2ea..03a6eb9 100644
--- a/crypto/asymmetric_keys/Kconfig
+++ b/crypto/asymmetric_keys/Kconfig
@@ -12,6 +12,8 @@ if ASYMMETRIC_KEY_TYPE
 config ASYMMETRIC_PUBLIC_KEY_SUBTYPE
 	tristate "Asymmetric public-key crypto algorithm subtype"
 	select MPILIB
+	select PUBLIC_KEY_ALGO_RSA
+	select CRYPTO_HASH_INFO
 	help
 	  This option provides support for asymmetric public key type handling.
 	  If signature generation and/or verification are to be used,
@@ -20,8 +22,8 @@ config ASYMMETRIC_PUBLIC_KEY_SUBTYPE
 
 config PUBLIC_KEY_ALGO_RSA
 	tristate "RSA public-key algorithm"
-	depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE
 	select MPILIB_EXTRA
+	select MPILIB
 	help
 	  This option enables support for the RSA algorithm (PKCS#1, RFC3447).
 
diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c
index cf80765..b77eb53 100644
--- a/crypto/asymmetric_keys/asymmetric_type.c
+++ b/crypto/asymmetric_keys/asymmetric_type.c
@@ -209,6 +209,7 @@ struct key_type key_type_asymmetric = {
 	.match		= asymmetric_key_match,
 	.destroy	= asymmetric_key_destroy,
 	.describe	= asymmetric_key_describe,
+	.def_lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE,
 };
 EXPORT_SYMBOL_GPL(key_type_asymmetric);
 
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index cb2e291..97eb0019 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -22,29 +22,25 @@
 
 MODULE_LICENSE("GPL");
 
-const char *const pkey_algo[PKEY_ALGO__LAST] = {
+const char *const pkey_algo_name[PKEY_ALGO__LAST] = {
 	[PKEY_ALGO_DSA]		= "DSA",
 	[PKEY_ALGO_RSA]		= "RSA",
 };
-EXPORT_SYMBOL_GPL(pkey_algo);
+EXPORT_SYMBOL_GPL(pkey_algo_name);
 
-const char *const pkey_hash_algo[PKEY_HASH__LAST] = {
-	[PKEY_HASH_MD4]		= "md4",
-	[PKEY_HASH_MD5]		= "md5",
-	[PKEY_HASH_SHA1]	= "sha1",
-	[PKEY_HASH_RIPE_MD_160]	= "rmd160",
-	[PKEY_HASH_SHA256]	= "sha256",
-	[PKEY_HASH_SHA384]	= "sha384",
-	[PKEY_HASH_SHA512]	= "sha512",
-	[PKEY_HASH_SHA224]	= "sha224",
+const struct public_key_algorithm *pkey_algo[PKEY_ALGO__LAST] = {
+#if defined(CONFIG_PUBLIC_KEY_ALGO_RSA) || \
+	defined(CONFIG_PUBLIC_KEY_ALGO_RSA_MODULE)
+	[PKEY_ALGO_RSA]		= &RSA_public_key_algorithm,
+#endif
 };
-EXPORT_SYMBOL_GPL(pkey_hash_algo);
+EXPORT_SYMBOL_GPL(pkey_algo);
 
-const char *const pkey_id_type[PKEY_ID_TYPE__LAST] = {
+const char *const pkey_id_type_name[PKEY_ID_TYPE__LAST] = {
 	[PKEY_ID_PGP]		= "PGP",
 	[PKEY_ID_X509]		= "X509",
 };
-EXPORT_SYMBOL_GPL(pkey_id_type);
+EXPORT_SYMBOL_GPL(pkey_id_type_name);
 
 /*
  * Provide a part of a description of the key for /proc/keys.
@@ -56,7 +52,7 @@ static void public_key_describe(const struct key *asymmetric_key,
 
 	if (key)
 		seq_printf(m, "%s.%s",
-			   pkey_id_type[key->id_type], key->algo->name);
+			   pkey_id_type_name[key->id_type], key->algo->name);
 }
 
 /*
@@ -78,21 +74,45 @@ EXPORT_SYMBOL_GPL(public_key_destroy);
 /*
  * Verify a signature using a public key.
  */
-static int public_key_verify_signature(const struct key *key,
-				       const struct public_key_signature *sig)
+int public_key_verify_signature(const struct public_key *pk,
+				const struct public_key_signature *sig)
 {
-	const struct public_key *pk = key->payload.data;
+	const struct public_key_algorithm *algo;
+
+	BUG_ON(!pk);
+	BUG_ON(!pk->mpi[0]);
+	BUG_ON(!pk->mpi[1]);
+	BUG_ON(!sig);
+	BUG_ON(!sig->digest);
+	BUG_ON(!sig->mpi[0]);
+
+	algo = pk->algo;
+	if (!algo) {
+		if (pk->pkey_algo >= PKEY_ALGO__LAST)
+			return -ENOPKG;
+		algo = pkey_algo[pk->pkey_algo];
+		if (!algo)
+			return -ENOPKG;
+	}
 
-	if (!pk->algo->verify_signature)
+	if (!algo->verify_signature)
 		return -ENOTSUPP;
 
-	if (sig->nr_mpi != pk->algo->n_sig_mpi) {
+	if (sig->nr_mpi != algo->n_sig_mpi) {
 		pr_debug("Signature has %u MPI not %u\n",
-			 sig->nr_mpi, pk->algo->n_sig_mpi);
+			 sig->nr_mpi, algo->n_sig_mpi);
 		return -EINVAL;
 	}
 
-	return pk->algo->verify_signature(pk, sig);
+	return algo->verify_signature(pk, sig);
+}
+EXPORT_SYMBOL_GPL(public_key_verify_signature);
+
+static int public_key_verify_signature_2(const struct key *key,
+					 const struct public_key_signature *sig)
+{
+	const struct public_key *pk = key->payload.data;
+	return public_key_verify_signature(pk, sig);
 }
 
 /*
@@ -103,6 +123,6 @@ struct asymmetric_key_subtype public_key_subtype = {
 	.name			= "public_key",
 	.describe		= public_key_describe,
 	.destroy		= public_key_destroy,
-	.verify_signature	= public_key_verify_signature,
+	.verify_signature	= public_key_verify_signature_2,
 };
 EXPORT_SYMBOL_GPL(public_key_subtype);
diff --git a/crypto/asymmetric_keys/public_key.h b/crypto/asymmetric_keys/public_key.h
index 5e5e356..5c37a22 100644
--- a/crypto/asymmetric_keys/public_key.h
+++ b/crypto/asymmetric_keys/public_key.h
@@ -28,3 +28,9 @@ struct public_key_algorithm {
 };
 
 extern const struct public_key_algorithm RSA_public_key_algorithm;
+
+/*
+ * public_key.c
+ */
+extern int public_key_verify_signature(const struct public_key *pk,
+				       const struct public_key_signature *sig);
diff --git a/crypto/asymmetric_keys/rsa.c b/crypto/asymmetric_keys/rsa.c
index 4a6a069..90a17f5 100644
--- a/crypto/asymmetric_keys/rsa.c
+++ b/crypto/asymmetric_keys/rsa.c
@@ -73,13 +73,13 @@ static const struct {
 	size_t size;
 } RSA_ASN1_templates[PKEY_HASH__LAST] = {
 #define _(X) { RSA_digest_info_##X, sizeof(RSA_digest_info_##X) }
-	[PKEY_HASH_MD5]		= _(MD5),
-	[PKEY_HASH_SHA1]	= _(SHA1),
-	[PKEY_HASH_RIPE_MD_160]	= _(RIPE_MD_160),
-	[PKEY_HASH_SHA256]	= _(SHA256),
-	[PKEY_HASH_SHA384]	= _(SHA384),
-	[PKEY_HASH_SHA512]	= _(SHA512),
-	[PKEY_HASH_SHA224]	= _(SHA224),
+	[HASH_ALGO_MD5]		= _(MD5),
+	[HASH_ALGO_SHA1]	= _(SHA1),
+	[HASH_ALGO_RIPE_MD_160]	= _(RIPE_MD_160),
+	[HASH_ALGO_SHA256]	= _(SHA256),
+	[HASH_ALGO_SHA384]	= _(SHA384),
+	[HASH_ALGO_SHA512]	= _(SHA512),
+	[HASH_ALGO_SHA224]	= _(SHA224),
 #undef _
 };
 
diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
index facbf26..2989316 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -47,6 +47,8 @@ void x509_free_certificate(struct x509_certificate *cert)
 		kfree(cert->subject);
 		kfree(cert->fingerprint);
 		kfree(cert->authority);
+		kfree(cert->sig.digest);
+		mpi_free(cert->sig.rsa.s);
 		kfree(cert);
 	}
 }
@@ -152,33 +154,33 @@ int x509_note_pkey_algo(void *context, size_t hdrlen,
 		return -ENOPKG; /* Unsupported combination */
 
 	case OID_md4WithRSAEncryption:
-		ctx->cert->sig_hash_algo = PKEY_HASH_MD5;
-		ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+		ctx->cert->sig.pkey_hash_algo = HASH_ALGO_MD5;
+		ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA;
 		break;
 
 	case OID_sha1WithRSAEncryption:
-		ctx->cert->sig_hash_algo = PKEY_HASH_SHA1;
-		ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+		ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA1;
+		ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA;
 		break;
 
 	case OID_sha256WithRSAEncryption:
-		ctx->cert->sig_hash_algo = PKEY_HASH_SHA256;
-		ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+		ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA256;
+		ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA;
 		break;
 
 	case OID_sha384WithRSAEncryption:
-		ctx->cert->sig_hash_algo = PKEY_HASH_SHA384;
-		ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+		ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA384;
+		ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA;
 		break;
 
 	case OID_sha512WithRSAEncryption:
-		ctx->cert->sig_hash_algo = PKEY_HASH_SHA512;
-		ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+		ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA512;
+		ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA;
 		break;
 
 	case OID_sha224WithRSAEncryption:
-		ctx->cert->sig_hash_algo = PKEY_HASH_SHA224;
-		ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+		ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA224;
+		ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA;
 		break;
 	}
 
@@ -203,8 +205,8 @@ int x509_note_signature(void *context, size_t hdrlen,
 		return -EINVAL;
 	}
 
-	ctx->cert->sig = value;
-	ctx->cert->sig_size = vlen;
+	ctx->cert->raw_sig = value;
+	ctx->cert->raw_sig_size = vlen;
 	return 0;
 }
 
@@ -343,8 +345,9 @@ int x509_extract_key_data(void *context, size_t hdrlen,
 	if (ctx->last_oid != OID_rsaEncryption)
 		return -ENOPKG;
 
-	/* There seems to be an extraneous 0 byte on the front of the data */
-	ctx->cert->pkey_algo = PKEY_ALGO_RSA;
+	ctx->cert->pub->pkey_algo = PKEY_ALGO_RSA;
+
+	/* Discard the BIT STRING metadata */
 	ctx->key = value + 1;
 	ctx->key_size = vlen - 1;
 	return 0;
diff --git a/crypto/asymmetric_keys/x509_parser.h b/crypto/asymmetric_keys/x509_parser.h
index f86dc5f..87d9cc2 100644
--- a/crypto/asymmetric_keys/x509_parser.h
+++ b/crypto/asymmetric_keys/x509_parser.h
@@ -9,6 +9,7 @@
  * 2 of the Licence, or (at your option) any later version.
  */
 
+#include <linux/time.h>
 #include <crypto/public_key.h>
 
 struct x509_certificate {
@@ -20,13 +21,11 @@ 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 pkey_algo	sig_pkey_algo : 8;	/* Signature public key algorithm */
-	enum pkey_hash_algo sig_hash_algo : 8;	/* Signature hash algorithm */
 	const void	*tbs;			/* Signed data */
-	size_t		tbs_size;		/* Size of signed data */
-	const void	*sig;			/* Signature data */
-	size_t		sig_size;		/* Size of sigature */
+	unsigned	tbs_size;		/* Size of signed data */
+	unsigned	raw_sig_size;		/* Size of sigature */
+	const void	*raw_sig;		/* Signature data */
+	struct public_key_signature sig;	/* Signature parameters */
 };
 
 /*
@@ -34,3 +33,10 @@ struct x509_certificate {
  */
 extern void x509_free_certificate(struct x509_certificate *cert);
 extern struct x509_certificate *x509_cert_parse(const void *data, size_t datalen);
+
+/*
+ * x509_public_key.c
+ */
+extern int x509_get_sig_params(struct x509_certificate *cert);
+extern int x509_check_signature(const struct public_key *pub,
+				struct x509_certificate *cert);
diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c
index 06007f0..f83300b 100644
--- a/crypto/asymmetric_keys/x509_public_key.c
+++ b/crypto/asymmetric_keys/x509_public_key.c
@@ -18,85 +18,162 @@
 #include <linux/asn1_decoder.h>
 #include <keys/asymmetric-subtype.h>
 #include <keys/asymmetric-parser.h>
+#include <keys/system_keyring.h>
 #include <crypto/hash.h>
 #include "asymmetric_keys.h"
 #include "public_key.h"
 #include "x509_parser.h"
 
-static const
-struct public_key_algorithm *x509_public_key_algorithms[PKEY_ALGO__LAST] = {
-	[PKEY_ALGO_DSA]		= NULL,
-#if defined(CONFIG_PUBLIC_KEY_ALGO_RSA) || \
-	defined(CONFIG_PUBLIC_KEY_ALGO_RSA_MODULE)
-	[PKEY_ALGO_RSA]		= &RSA_public_key_algorithm,
-#endif
-};
+/*
+ * Find a key in the given keyring by issuer and authority.
+ */
+static struct key *x509_request_asymmetric_key(
+	struct key *keyring,
+	const char *signer, size_t signer_len,
+	const char *authority, size_t auth_len)
+{
+	key_ref_t key;
+	char *id;
+
+	/* Construct an identifier. */
+	id = kmalloc(signer_len + 2 + auth_len + 1, GFP_KERNEL);
+	if (!id)
+		return ERR_PTR(-ENOMEM);
+
+	memcpy(id, signer, signer_len);
+	id[signer_len + 0] = ':';
+	id[signer_len + 1] = ' ';
+	memcpy(id + signer_len + 2, authority, auth_len);
+	id[signer_len + 2 + auth_len] = 0;
+
+	pr_debug("Look up: \"%s\"\n", id);
+
+	key = keyring_search(make_key_ref(keyring, 1),
+			     &key_type_asymmetric, id);
+	if (IS_ERR(key))
+		pr_debug("Request for module key '%s' err %ld\n",
+			 id, PTR_ERR(key));
+	kfree(id);
+
+	if (IS_ERR(key)) {
+		switch (PTR_ERR(key)) {
+			/* Hide some search errors */
+		case -EACCES:
+		case -ENOTDIR:
+		case -EAGAIN:
+			return ERR_PTR(-ENOKEY);
+		default:
+			return ERR_CAST(key);
+		}
+	}
+
+	pr_devel("<==%s() = 0 [%x]\n", __func__, key_serial(key_ref_to_ptr(key)));
+	return key_ref_to_ptr(key);
+}
 
 /*
- * Check the signature on a certificate using the provided public key
+ * Set up the signature parameters in an X.509 certificate.  This involves
+ * digesting the signed data and extracting the signature.
  */
-static int x509_check_signature(const struct public_key *pub,
-				const struct x509_certificate *cert)
+int x509_get_sig_params(struct x509_certificate *cert)
 {
-	struct public_key_signature *sig;
 	struct crypto_shash *tfm;
 	struct shash_desc *desc;
 	size_t digest_size, desc_size;
+	void *digest;
 	int ret;
 
 	pr_devel("==>%s()\n", __func__);
-	
+
+	if (cert->sig.rsa.s)
+		return 0;
+
+	cert->sig.rsa.s = mpi_read_raw_data(cert->raw_sig, cert->raw_sig_size);
+	if (!cert->sig.rsa.s)
+		return -ENOMEM;
+	cert->sig.nr_mpi = 1;
+
 	/* Allocate the hashing algorithm we're going to need and find out how
 	 * big the hash operational data will be.
 	 */
-	tfm = crypto_alloc_shash(pkey_hash_algo[cert->sig_hash_algo], 0, 0);
+	tfm = crypto_alloc_shash(hash_algo_name[cert->sig.pkey_hash_algo], 0, 0);
 	if (IS_ERR(tfm))
 		return (PTR_ERR(tfm) == -ENOENT) ? -ENOPKG : PTR_ERR(tfm);
 
 	desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
 	digest_size = crypto_shash_digestsize(tfm);
 
-	/* We allocate the hash operational data storage on the end of our
-	 * context data.
+	/* We allocate the hash operational data storage on the end of the
+	 * digest storage space.
 	 */
 	ret = -ENOMEM;
-	sig = kzalloc(sizeof(*sig) + desc_size + digest_size, GFP_KERNEL);
-	if (!sig)
-		goto error_no_sig;
+	digest = kzalloc(digest_size + desc_size, GFP_KERNEL);
+	if (!digest)
+		goto error;
 
-	sig->pkey_hash_algo	= cert->sig_hash_algo;
-	sig->digest		= (u8 *)sig + sizeof(*sig) + desc_size;
-	sig->digest_size	= digest_size;
+	cert->sig.digest = digest;
+	cert->sig.digest_size = digest_size;
 
-	desc = (void *)sig + sizeof(*sig);
-	desc->tfm	= tfm;
-	desc->flags	= CRYPTO_TFM_REQ_MAY_SLEEP;
+	desc = digest + digest_size;
+	desc->tfm = tfm;
+	desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	ret = crypto_shash_init(desc);
 	if (ret < 0)
 		goto error;
+	might_sleep();
+	ret = crypto_shash_finup(desc, cert->tbs, cert->tbs_size, digest);
+error:
+	crypto_free_shash(tfm);
+	pr_devel("<==%s() = %d\n", __func__, ret);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(x509_get_sig_params);
 
-	ret = -ENOMEM;
-	sig->rsa.s = mpi_read_raw_data(cert->sig, cert->sig_size);
-	if (!sig->rsa.s)
-		goto error;
+/*
+ * Check the signature on a certificate using the provided public key
+ */
+int x509_check_signature(const struct public_key *pub,
+			 struct x509_certificate *cert)
+{
+	int ret;
 
-	ret = crypto_shash_finup(desc, cert->tbs, cert->tbs_size, sig->digest);
-	if (ret < 0)
-		goto error_mpi;
+	pr_devel("==>%s()\n", __func__);
 
-	ret = pub->algo->verify_signature(pub, sig);
+	ret = x509_get_sig_params(cert);
+	if (ret < 0)
+		return ret;
 
+	ret = public_key_verify_signature(pub, &cert->sig);
 	pr_debug("Cert Verification: %d\n", ret);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(x509_check_signature);
 
-error_mpi:
-	mpi_free(sig->rsa.s);
-error:
-	kfree(sig);
-error_no_sig:
-	crypto_free_shash(tfm);
+/*
+ * Check the new certificate against the ones in the trust keyring.  If one of
+ * those is the signing key and validates the new certificate, then mark the
+ * new certificate as being trusted.
+ *
+ * Return 0 if the new certificate was successfully validated, 1 if we couldn't
+ * find a matching parent certificate in the trusted list and an error if there
+ * is a matching certificate but the signature check fails.
+ */
+static int x509_validate_trust(struct x509_certificate *cert,
+			       struct key *trust_keyring)
+{
+	const struct public_key *pk;
+	struct key *key;
+	int ret = 1;
 
-	pr_devel("<==%s() = %d\n", __func__, ret);
+	key = x509_request_asymmetric_key(trust_keyring,
+					  cert->issuer, strlen(cert->issuer),
+					  cert->authority,
+					  strlen(cert->authority));
+	if (!IS_ERR(key))  {
+		pk = key->payload.data;
+		ret = x509_check_signature(pk, cert);
+	}
 	return ret;
 }
 
@@ -106,7 +183,6 @@ error_no_sig:
 static int x509_key_preparse(struct key_preparsed_payload *prep)
 {
 	struct x509_certificate *cert;
-	struct tm now;
 	size_t srlen, sulen;
 	char *desc = NULL;
 	int ret;
@@ -117,7 +193,18 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
 
 	pr_devel("Cert Issuer: %s\n", cert->issuer);
 	pr_devel("Cert Subject: %s\n", cert->subject);
-	pr_devel("Cert Key Algo: %s\n", pkey_algo[cert->pkey_algo]);
+
+	if (cert->pub->pkey_algo >= PKEY_ALGO__LAST ||
+	    cert->sig.pkey_algo >= PKEY_ALGO__LAST ||
+	    cert->sig.pkey_hash_algo >= PKEY_HASH__LAST ||
+	    !pkey_algo[cert->pub->pkey_algo] ||
+	    !pkey_algo[cert->sig.pkey_algo] ||
+	    !hash_algo_name[cert->sig.pkey_hash_algo]) {
+		ret = -ENOPKG;
+		goto error_free_cert;
+	}
+
+	pr_devel("Cert Key Algo: %s\n", pkey_algo_name[cert->pub->pkey_algo]);
 	pr_devel("Cert Valid From: %04ld-%02d-%02d %02d:%02d:%02d\n",
 		 cert->valid_from.tm_year + 1900, cert->valid_from.tm_mon + 1,
 		 cert->valid_from.tm_mday, cert->valid_from.tm_hour,
@@ -127,61 +214,29 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
 		 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 + %s\n",
-		 pkey_algo[cert->sig_pkey_algo],
-		 pkey_hash_algo[cert->sig_hash_algo]);
+		 pkey_algo_name[cert->sig.pkey_algo],
+		 hash_algo_name[cert->sig.pkey_hash_algo]);
 
-	if (!cert->fingerprint || !cert->authority) {
-		pr_warn("Cert for '%s' must have SubjKeyId and AuthKeyId extensions\n",
+	if (!cert->fingerprint) {
+		pr_warn("Cert for '%s' must have a SubjKeyId extension\n",
 			cert->subject);
 		ret = -EKEYREJECTED;
 		goto error_free_cert;
 	}
 
-	time_to_tm(CURRENT_TIME.tv_sec, 0, &now);
-	pr_devel("Now: %04ld-%02d-%02d %02d:%02d:%02d\n",
-		 now.tm_year + 1900, now.tm_mon + 1, now.tm_mday,
-		 now.tm_hour, now.tm_min,  now.tm_sec);
-	if (now.tm_year < cert->valid_from.tm_year ||
-	    (now.tm_year == cert->valid_from.tm_year &&
-	     (now.tm_mon < cert->valid_from.tm_mon ||
-	      (now.tm_mon == cert->valid_from.tm_mon &&
-	       (now.tm_mday < cert->valid_from.tm_mday ||
-		(now.tm_mday == cert->valid_from.tm_mday &&
-		 (now.tm_hour < cert->valid_from.tm_hour ||
-		  (now.tm_hour == cert->valid_from.tm_hour &&
-		   (now.tm_min < cert->valid_from.tm_min ||
-		    (now.tm_min == cert->valid_from.tm_min &&
-		     (now.tm_sec < cert->valid_from.tm_sec
-		      ))))))))))) {
-		pr_warn("Cert %s is not yet valid\n", cert->fingerprint);
-		ret = -EKEYREJECTED;
-		goto error_free_cert;
-	}
-	if (now.tm_year > cert->valid_to.tm_year ||
-	    (now.tm_year == cert->valid_to.tm_year &&
-	     (now.tm_mon > cert->valid_to.tm_mon ||
-	      (now.tm_mon == cert->valid_to.tm_mon &&
-	       (now.tm_mday > cert->valid_to.tm_mday ||
-		(now.tm_mday == cert->valid_to.tm_mday &&
-		 (now.tm_hour > cert->valid_to.tm_hour ||
-		  (now.tm_hour == cert->valid_to.tm_hour &&
-		   (now.tm_min > cert->valid_to.tm_min ||
-		    (now.tm_min == cert->valid_to.tm_min &&
-		     (now.tm_sec > cert->valid_to.tm_sec
-		      ))))))))))) {
-		pr_warn("Cert %s has expired\n", cert->fingerprint);
-		ret = -EKEYEXPIRED;
-		goto error_free_cert;
-	}
-
-	cert->pub->algo = x509_public_key_algorithms[cert->pkey_algo];
+	cert->pub->algo = pkey_algo[cert->pub->pkey_algo];
 	cert->pub->id_type = PKEY_ID_X509;
 
-	/* Check the signature on the key */
-	if (strcmp(cert->fingerprint, cert->authority) == 0) {
-		ret = x509_check_signature(cert->pub, cert);
+	/* Check the signature on the key if it appears to be self-signed */
+	if (!cert->authority ||
+	    strcmp(cert->fingerprint, cert->authority) == 0) {
+		ret = x509_check_signature(cert->pub, cert); /* self-signed */
 		if (ret < 0)
 			goto error_free_cert;
+	} else {
+		ret = x509_validate_trust(cert, system_trusted_keyring);
+		if (!ret)
+			prep->trusted = 1;
 	}
 
 	/* Propose a description */
@@ -237,3 +292,6 @@ static void __exit x509_key_exit(void)
 
 module_init(x509_key_init);
 module_exit(x509_key_exit);
+
+MODULE_DESCRIPTION("X.509 certificate parser");
+MODULE_LICENSE("GPL");
diff --git a/crypto/hash_info.c b/crypto/hash_info.c
new file mode 100644
index 0000000..3e7ff46
--- /dev/null
+++ b/crypto/hash_info.c
@@ -0,0 +1,56 @@
+/*
+ * Hash Info: Hash algorithms information
+ *
+ * Copyright (c) 2013 Dmitry Kasatkin <d.kasatkin@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ */
+
+#include <linux/export.h>
+#include <crypto/hash_info.h>
+
+const char *const hash_algo_name[HASH_ALGO__LAST] = {
+	[HASH_ALGO_MD4]		= "md4",
+	[HASH_ALGO_MD5]		= "md5",
+	[HASH_ALGO_SHA1]	= "sha1",
+	[HASH_ALGO_RIPE_MD_160]	= "rmd160",
+	[HASH_ALGO_SHA256]	= "sha256",
+	[HASH_ALGO_SHA384]	= "sha384",
+	[HASH_ALGO_SHA512]	= "sha512",
+	[HASH_ALGO_SHA224]	= "sha224",
+	[HASH_ALGO_RIPE_MD_128]	= "rmd128",
+	[HASH_ALGO_RIPE_MD_256]	= "rmd256",
+	[HASH_ALGO_RIPE_MD_320]	= "rmd320",
+	[HASH_ALGO_WP_256]	= "wp256",
+	[HASH_ALGO_WP_384]	= "wp384",
+	[HASH_ALGO_WP_512]	= "wp512",
+	[HASH_ALGO_TGR_128]	= "tgr128",
+	[HASH_ALGO_TGR_160]	= "tgr160",
+	[HASH_ALGO_TGR_192]	= "tgr192",
+};
+EXPORT_SYMBOL_GPL(hash_algo_name);
+
+const int hash_digest_size[HASH_ALGO__LAST] = {
+	[HASH_ALGO_MD4]		= MD5_DIGEST_SIZE,
+	[HASH_ALGO_MD5]		= MD5_DIGEST_SIZE,
+	[HASH_ALGO_SHA1]	= SHA1_DIGEST_SIZE,
+	[HASH_ALGO_RIPE_MD_160]	= RMD160_DIGEST_SIZE,
+	[HASH_ALGO_SHA256]	= SHA256_DIGEST_SIZE,
+	[HASH_ALGO_SHA384]	= SHA384_DIGEST_SIZE,
+	[HASH_ALGO_SHA512]	= SHA512_DIGEST_SIZE,
+	[HASH_ALGO_SHA224]	= SHA224_DIGEST_SIZE,
+	[HASH_ALGO_RIPE_MD_128]	= RMD128_DIGEST_SIZE,
+	[HASH_ALGO_RIPE_MD_256]	= RMD256_DIGEST_SIZE,
+	[HASH_ALGO_RIPE_MD_320]	= RMD320_DIGEST_SIZE,
+	[HASH_ALGO_WP_256]	= WP256_DIGEST_SIZE,
+	[HASH_ALGO_WP_384]	= WP384_DIGEST_SIZE,
+	[HASH_ALGO_WP_512]	= WP512_DIGEST_SIZE,
+	[HASH_ALGO_TGR_128]	= TGR128_DIGEST_SIZE,
+	[HASH_ALGO_TGR_160]	= TGR160_DIGEST_SIZE,
+	[HASH_ALGO_TGR_192]	= TGR192_DIGEST_SIZE,
+};
+EXPORT_SYMBOL_GPL(hash_digest_size);