[RFC PATCH] KEYS: Provide keyctls to do public key operations [ver #2]

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Here's v2 of the patch with the reported errors fixed.  It's still untested by
me, however.

David
---
KEYS: Provide keyctls to do public key operations

From: David Howells <dhowells@xxxxxxxxxx>

Provide keyctl functions to do public key operations (sign, verify, encrypt
and decrypt) if the target key supports them, plus a query function to find
out about the key.

Not-yet-signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---
 Documentation/security/keys.txt           |  105 +++++++++
 crypto/asymmetric_keys/pkcs7_parser.c     |    1 
 crypto/asymmetric_keys/public_key.c       |   38 +++
 crypto/asymmetric_keys/signature.c        |  150 +++++++++++++
 crypto/asymmetric_keys/x509_cert_parser.c |   21 +-
 include/crypto/public_key.h               |   13 +
 include/keys/asymmetric-subtype.h         |   13 +
 include/linux/keyctl.h                    |   36 +++
 include/uapi/linux/keyctl.h               |   27 ++
 security/keys/Makefile                    |    1 
 security/keys/compat.c                    |   11 +
 security/keys/internal.h                  |   35 +++
 security/keys/keyctl.c                    |   21 ++
 security/keys/keyctl_pkey.c               |  325 +++++++++++++++++++++++++++++
 14 files changed, 782 insertions(+), 15 deletions(-)
 create mode 100644 include/linux/keyctl.h
 create mode 100644 security/keys/keyctl_pkey.c

diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt
index 20d05719bceb..de90cdaa1a4e 100644
--- a/Documentation/security/keys.txt
+++ b/Documentation/security/keys.txt
@@ -854,6 +854,111 @@ The keyctl syscall functions are:
      supported, error ENOKEY if the key could not be found, or error
      EACCES if the key is not readable by the caller.
 
+
+ (*) Query an asymmetric key.
+
+	long keyctl(KEYCTL_PKEY_QUERY, key_serial_t key,
+		    struct keyctl_pkey_query *info);
+
+     Get information about an asymmetric key.  The information is returned in
+     the keyctl_pkey_query struct:
+
+	__u32	supported_ops;
+
+     A bit mask of flags indicating which ops are supported.  This is
+     constructed from a bitwise-OR of:
+
+	KEYCTL_SUPPORTS_{ENCRYPT,DECRYPT,SIGN,VERIFY}
+
+	__u32	key_size;
+
+     The size in bits of the key.
+
+	__u16	max_data_size;
+	__u16	max_sig_size;
+	__u16	max_enc_size;
+	__u16	max_dec_size;
+
+     The maximum sizes in bytes of a blob of data to be signed, a signature
+     blob, a blob to be encrypted and a blob to be decypted.
+
+     If successful, 0 is returned.  If the key is not an asymmetric key,
+     EOPNOTSUPP is returned.
+
+
+ (*) Encrypt, decrypt, sign or verify a blob using an asymmetric key.
+
+	long keyctl(KEYCTL_PKEY_ENCRYPT,
+		    const struct keyctl_pkey_params *params,
+		    const char *info,
+		    const void *data,
+		    void *enc);
+
+	long keyctl(KEYCTL_PKEY_DECRYPT,
+		    const struct keyctl_pkey_params *params,
+		    const char *info,
+		    const void *enc,
+		    void *data);
+
+	long keyctl(KEYCTL_PKEY_SIGN,
+		    const struct keyctl_pkey_params *params,
+		    const char *info,
+		    const void *data,
+		    void *enc);
+
+	long keyctl(KEYCTL_PKEY_VERIFY,
+		    const struct keyctl_pkey_params *params,
+		    const char *info,
+		    const void *data,
+		    const void *enc);
+
+     Use an asymmetric key to perform a public-key cryptographic operation a
+     blob of data.  For encryption and verification, the asymmetric key may
+     only need the public parts to be available, but for decryption and signing
+     the private parts are required also.
+
+     The parameter block pointed to by params contains a number of integer
+     values:
+
+	__s32		key_id;
+	__s32		password_id;
+	__u32		data_len;
+	__u32		enc_len;
+
+     key_id is the ID of the asymmetric key to be used.  data_len indicates the
+     length of the data or buffer pointed to by data whilst enc_len indicates
+     the length of the data or buffer pointed to by enc.
+
+     If the key must be unlocked with a password before it can be used,
+     password_id should point to a logon-type key that holds this.
+
+     info is a string of key=value pairs that supply supplementary
+     information.  These include:
+
+	enc=<encoding>	The encoding of the encrypted/signature blob.  This can
+			be "pkcs1" for RSASSA-PKCS1-v1.5 or RSAES-PKCS1-v1.5;
+			"pss" for "RSASSA-PSS"; "oaep" for "RSAES-OAEP".  If
+			omitted or is "raw", the raw output of the encryption
+			function is specified.
+
+	hash=<algo>	If the data buffer contains the output of a hash
+			function and the encoding includes some indication of
+			which hash function was used, the hash function can be
+			specified with this, eg. "hash=sha256".
+
+     For encryption, data points to the data blob to be encrypted whilst enc
+     points to a buffer to hold the encrypted output.  Decryption is the mirror
+     image of this - and note that the arguments are reversed.
+
+     For signing and verifying, data holds the blob to be signed in both cases
+     (this is typically the output of a digest function).  When signing, enc
+     points to a buffer into which the signature will be written, whereas with
+     verification, enc points to the signature to be verified.
+
+     If successful, encrypt, decrypt and sign all return the amount of data
+     written into the output buffer.  Verification returns 0 on success.
+
+
 ===============
 KERNEL SERVICES
 ===============
diff --git a/crypto/asymmetric_keys/pkcs7_parser.c b/crypto/asymmetric_keys/pkcs7_parser.c
index af4cd8649117..5f0c6755a55b 100644
--- a/crypto/asymmetric_keys/pkcs7_parser.c
+++ b/crypto/asymmetric_keys/pkcs7_parser.c
@@ -261,6 +261,7 @@ int pkcs7_sig_note_pkey_algo(void *context, size_t hdrlen,
 	switch (ctx->last_oid) {
 	case OID_rsaEncryption:
 		ctx->sinfo->sig->pkey_algo = "rsa";
+		ctx->sinfo->sig->encoding = "pkcs1";
 		break;
 	default:
 		printk("Unsupported pkey algo: %u\n", ctx->last_oid);
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index fd76b5fc3b3a..9379adb169ff 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -57,6 +57,40 @@ static void public_key_destroy(void *payload0, void *payload3)
 	public_key_signature_free(payload3);
 }
 
+/*
+ * Query information about a key.
+ */
+static int software_key_query(const struct key *key,
+			      struct kernel_pkey_query *info)
+{
+	struct crypto_akcipher *tfm;
+	struct public_key *pkey = key->payload.data[asym_crypto];
+	int ret, len;
+
+	tfm = crypto_alloc_akcipher(pkey->pkey_algo, 0, 0);
+	if (IS_ERR(tfm))
+		return PTR_ERR(tfm);
+
+	ret = crypto_akcipher_set_pub_key(tfm, pkey->key, pkey->keylen);
+	if (ret < 0)
+		goto error_free_tfm;
+
+	len = crypto_akcipher_maxsize(tfm);
+	info->key_size = len * 8;
+	info->max_data_size = len;
+	info->max_sig_size = len;
+	info->max_enc_size = len;
+	info->max_dec_size = len;
+	info->supported_ops = KEYCTL_SUPPORTS_VERIFY;
+	ret = 0;
+
+error_free_tfm:
+	crypto_free_akcipher(tfm);
+	pr_devel("<==%s() = %d\n", __func__, ret);
+	return ret;
+}
+
+
 struct public_key_completion {
 	struct completion completion;
 	int err;
@@ -97,7 +131,8 @@ int public_key_verify_signature(const struct public_key *pkey,
 	BUG_ON(!sig->s);
 
 	alg_name = sig->pkey_algo;
-	if (strcmp(sig->pkey_algo, "rsa") == 0) {
+	if (strcmp(sig->pkey_algo, "rsa") == 0 &&
+	    strcmp(sig->encoding, "pkcs1") == 0) {
 		/* The data wangled by the RSA algorithm is typically padded
 		 * and encoded in some manner, such as EMSA-PKCS1-1_5 [RFC3447
 		 * sec 8.2].
@@ -179,6 +214,7 @@ struct asymmetric_key_subtype public_key_subtype = {
 	.name_len		= sizeof("public_key") - 1,
 	.describe		= public_key_describe,
 	.destroy		= public_key_destroy,
+	.query			= software_key_query,
 	.verify_signature	= public_key_verify_signature_2,
 };
 EXPORT_SYMBOL_GPL(public_key_subtype);
diff --git a/crypto/asymmetric_keys/signature.c b/crypto/asymmetric_keys/signature.c
index 11b7ba170904..8ecbeda16b53 100644
--- a/crypto/asymmetric_keys/signature.c
+++ b/crypto/asymmetric_keys/signature.c
@@ -37,6 +37,156 @@ void public_key_signature_free(struct public_key_signature *sig)
 EXPORT_SYMBOL_GPL(public_key_signature_free);
 
 /**
+ * query_asymmetric_key - Get information about an aymmetric key.
+ * @key: The key to query
+ * @info: Where to put the information.
+ */
+int query_asymmetric_key(const struct key *key,
+			 struct kernel_pkey_query *info)
+{
+	const struct asymmetric_key_subtype *subtype;
+	int ret;
+
+	pr_devel("==>%s()\n", __func__);
+
+	if (key->type != &key_type_asymmetric)
+		return -EINVAL;
+	subtype = asymmetric_key_subtype(key);
+	if (!subtype ||
+	    !key->payload.data[0])
+		return -EINVAL;
+
+	ret = subtype->query(key, info);
+
+	pr_devel("<==%s() = %d\n", __func__, ret);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(query_asymmetric_key);
+
+/**
+ * encrypt_blob - Encrypt data using an asymmetric key
+ * @params: Various parameters
+ * @data: Data blob to be encrypted, length params->data_len
+ * @enc: Encrypted data buffer, length params->enc_len
+ *
+ * Encrypt the specified data blob using the private key specified by
+ * params->key.  The encrypted data is wrapped in an encoding if
+ * params->encoding is specified (eg. "pkcs1").
+ *
+ * If the key needs to be unlocked, a password can be supplied in a logon key
+ * specified by params->password.
+ *
+ * Returns the length of the data placed in the encrypted data buffer or an
+ * error.
+ */
+int encrypt_blob(struct kernel_pkey_params *params,
+		 const void *data, void *enc)
+{
+	const struct asymmetric_key_subtype *subtype;
+	struct key *key = params->key;
+	int ret;
+
+	pr_devel("==>%s()\n", __func__);
+
+	if (key->type != &key_type_asymmetric)
+		return -EINVAL;
+	subtype = asymmetric_key_subtype(key);
+	if (!subtype ||
+	    !key->payload.data[0])
+		return -EINVAL;
+	if (!subtype->encrypt_blob)
+		return -ENOTSUPP;
+
+	ret = subtype->encrypt_blob(params, data, enc);
+
+	pr_devel("<==%s() = %d\n", __func__, ret);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(encrypt_blob);
+
+/**
+ * decrypt_blob - Decrypt data using an asymmetric key
+ * @params: Various parameters
+ * @enc: Encrypted data to be decrypted, length params->enc_len
+ * @data: Decrypted data buffer, length params->data_len
+ *
+ * Decrypt the specified data blob using the private key specified by
+ * params->key.  The decrypted data is wrapped in an encoding if
+ * params->encoding is specified (eg. "pkcs1").
+ *
+ * If the private key needs to be unlocked, a password can be supplied in a
+ * logon key specified by params->password.
+ *
+ * Returns the length of the data placed in the decrypted data buffer or an
+ * error.
+ */
+int decrypt_blob(struct kernel_pkey_params *params,
+		 const void *enc, void *data)
+{
+	const struct asymmetric_key_subtype *subtype;
+	struct key *key = params->key;
+	int ret;
+
+	pr_devel("==>%s()\n", __func__);
+
+	if (key->type != &key_type_asymmetric)
+		return -EINVAL;
+	subtype = asymmetric_key_subtype(key);
+	if (!subtype ||
+	    !key->payload.data[0])
+		return -EINVAL;
+	if (!subtype->decrypt_blob)
+		return -ENOTSUPP;
+
+	ret = subtype->decrypt_blob(params, enc, data);
+
+	pr_devel("<==%s() = %d\n", __func__, ret);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(decrypt_blob);
+
+/**
+ * create_signature - Sign some data using an asymmetric key
+ * @params: Various parameters
+ * @data: Data blob to be signed, length params->data_len
+ * @enc: Signature buffer, length params->enc_len
+ *
+ * Sign the specified data blob using the private key specified by params->key.
+ * The signature is wrapped in an encoding if params->encoding is specified
+ * (eg. "pkcs1").  If the encoding needs to know the digest type, this can be
+ * passed through params->hash_algo (eg. "sha1").
+ *
+ * If the private key needs to be unlocked, a password can be supplied in a
+ * logon key specified by params->password.
+ *
+ * Returns the length of the data placed in the signature buffer or an error.
+ */
+int create_signature(struct kernel_pkey_params *params,
+		     const void *data, void *enc)
+{
+	const struct asymmetric_key_subtype *subtype;
+	struct key *key = params->key;
+	int ret;
+
+	pr_devel("==>%s()\n", __func__);
+
+	if (key->type != &key_type_asymmetric)
+		return -EINVAL;
+	subtype = asymmetric_key_subtype(key);
+	if (!subtype ||
+	    !key->payload.data[0])
+		return -EINVAL;
+	if (!subtype->create_signature)
+		return -ENOTSUPP;
+
+	ret = subtype->create_signature(params, data, enc);
+
+	pr_devel("<==%s() = %d\n", __func__, ret);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(create_signature);
+
+/**
  * verify_signature - Initiate the use of an asymmetric key to verify a signature
  * @key: The asymmetric key to verify against
  * @sig: The signature to check
diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
index 865f46ea724f..1f1899d5ab43 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -199,35 +199,32 @@ int x509_note_pkey_algo(void *context, size_t hdrlen,
 
 	case OID_md4WithRSAEncryption:
 		ctx->cert->sig->hash_algo = "md4";
-		ctx->cert->sig->pkey_algo = "rsa";
-		break;
+		goto rsa_pkcs1;
 
 	case OID_sha1WithRSAEncryption:
 		ctx->cert->sig->hash_algo = "sha1";
-		ctx->cert->sig->pkey_algo = "rsa";
-		break;
+		goto rsa_pkcs1;
 
 	case OID_sha256WithRSAEncryption:
 		ctx->cert->sig->hash_algo = "sha256";
-		ctx->cert->sig->pkey_algo = "rsa";
-		break;
+		goto rsa_pkcs1;
 
 	case OID_sha384WithRSAEncryption:
 		ctx->cert->sig->hash_algo = "sha384";
-		ctx->cert->sig->pkey_algo = "rsa";
-		break;
+		goto rsa_pkcs1;
 
 	case OID_sha512WithRSAEncryption:
 		ctx->cert->sig->hash_algo = "sha512";
-		ctx->cert->sig->pkey_algo = "rsa";
-		break;
+		goto rsa_pkcs1;
 
 	case OID_sha224WithRSAEncryption:
 		ctx->cert->sig->hash_algo = "sha224";
-		ctx->cert->sig->pkey_algo = "rsa";
-		break;
+		goto rsa_pkcs1;
 	}
 
+rsa_pkcs1:
+	ctx->cert->sig->pkey_algo = "rsa";
+	ctx->cert->sig->encoding = "pkcs1";
 	ctx->algo_oid = ctx->last_oid;
 	return 0;
 }
diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h
index 882ca0e1e7a5..a5bdfef2d243 100644
--- a/include/crypto/public_key.h
+++ b/include/crypto/public_key.h
@@ -14,6 +14,8 @@
 #ifndef _LINUX_PUBLIC_KEY_H
 #define _LINUX_PUBLIC_KEY_H
 
+#include <linux/keyctl.h>
+
 /*
  * Cryptographic data for the public-key subtype of the asymmetric key type.
  *
@@ -40,6 +42,7 @@ struct public_key_signature {
 	u8 digest_size;		/* Number of bytes in digest */
 	const char *pkey_algo;
 	const char *hash_algo;
+	const char *encoding;
 };
 
 extern void public_key_signature_free(struct public_key_signature *sig);
@@ -54,8 +57,14 @@ extern int restrict_link_by_signature(struct key *trust_keyring,
 				      const struct key_type *type,
 				      const union key_payload *payload);
 
-extern int verify_signature(const struct key *key,
-			    const struct public_key_signature *sig);
+extern int query_asymmetric_key(const struct key *,
+				struct kernel_pkey_query *);
+
+extern int encrypt_blob(struct kernel_pkey_params *, const void *, void *);
+extern int decrypt_blob(struct kernel_pkey_params *, const void *, void *);
+extern int create_signature(struct kernel_pkey_params *, const void *, void *);
+extern int verify_signature(const struct key *,
+			    const struct public_key_signature *);
 
 int public_key_verify_signature(const struct public_key *pkey,
 				const struct public_key_signature *sig);
diff --git a/include/keys/asymmetric-subtype.h b/include/keys/asymmetric-subtype.h
index 2480469ce8fb..b3a6e1a090c2 100644
--- a/include/keys/asymmetric-subtype.h
+++ b/include/keys/asymmetric-subtype.h
@@ -17,6 +17,8 @@
 #include <linux/seq_file.h>
 #include <keys/asymmetric-type.h>
 
+struct kernel_pkey_query;
+struct kernel_pkey_params;
 struct public_key_signature;
 
 /*
@@ -34,6 +36,17 @@ struct asymmetric_key_subtype {
 	/* Destroy a key of this subtype */
 	void (*destroy)(void *payload_crypto, void *payload_auth);
 
+	int (*query)(const struct key *key, struct kernel_pkey_query *info);
+
+	int (*encrypt_blob)(struct kernel_pkey_params *params,
+			    const void *data, void *enc);
+
+	int (*decrypt_blob)(struct kernel_pkey_params *params,
+			    const void *enc, void *data);
+
+	int (*create_signature)(struct kernel_pkey_params *params,
+				const void *data, void *enc);
+
 	/* Verify the signature on a key of this subtype (optional) */
 	int (*verify_signature)(const struct key *key,
 				const struct public_key_signature *sig);
diff --git a/include/linux/keyctl.h b/include/linux/keyctl.h
new file mode 100644
index 000000000000..54afe345b75a
--- /dev/null
+++ b/include/linux/keyctl.h
@@ -0,0 +1,36 @@
+/* keyctl kernel bits
+ *
+ * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@xxxxxxxxxx)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#ifndef __LINUX_KEYCTL_H
+#define __LINUX_KEYCTL_H
+
+#include <uapi/linux/keyctl.h>
+
+struct kernel_pkey_query {
+	__u32		supported_ops;	/* Which ops are supported */
+	__u32		key_size;	/* Size of the key in bits */
+	__u16		max_data_size;	/* Maximum size of raw data to sign in bytes */
+	__u16		max_sig_size;	/* Maximum size of signature in bytes */
+	__u16		max_enc_size;	/* Maximum size of encrypted blob in bytes */
+	__u16		max_dec_size;	/* Maximum size of decrypted blob in bytes */
+};
+
+struct kernel_pkey_params {
+	struct key	*key;
+	struct key	*password;
+	const char	*encoding;	/* Encoding (eg. "oaep" or NULL for raw) */
+	const char	*hash_algo;	/* Digest algorithm used (eg. "sha1") or NULL if N/A */
+	char		*info;		/* Modified info string to be released later */
+	__u32		data_len;	/* Unencrypted/unsigned data (buffer) size */
+	__u32		enc_len;	/* Encrypted data/signature (buffer) size */
+};
+
+#endif /* __LINUX_KEYCTL_H */
diff --git a/include/uapi/linux/keyctl.h b/include/uapi/linux/keyctl.h
index 86eddd6241f3..37248ab64b02 100644
--- a/include/uapi/linux/keyctl.h
+++ b/include/uapi/linux/keyctl.h
@@ -60,6 +60,11 @@
 #define KEYCTL_INVALIDATE		21	/* invalidate a key */
 #define KEYCTL_GET_PERSISTENT		22	/* get a user's persistent keyring */
 #define KEYCTL_DH_COMPUTE		23	/* Compute Diffie-Hellman values */
+#define KEYCTL_PKEY_QUERY		24	/* Query public key parameters */
+#define KEYCTL_PKEY_ENCRYPT		25	/* Encrypt a blob using a public key */
+#define KEYCTL_PKEY_DECRYPT		26	/* Decrypt a blob using a public key */
+#define KEYCTL_PKEY_SIGN		27	/* Create a public key signature */
+#define KEYCTL_PKEY_VERIFY		28	/* Verify a public key signature */
 
 /* keyctl structures */
 struct keyctl_dh_params {
@@ -68,4 +73,26 @@ struct keyctl_dh_params {
 	__s32 base;
 };
 
+struct keyctl_pkey_query {
+	__u32		supported_ops;	/* Which ops are supported */
+#define KEYCTL_SUPPORTS_ENCRYPT		0x01
+#define KEYCTL_SUPPORTS_DECRYPT		0x02
+#define KEYCTL_SUPPORTS_SIGN		0x04
+#define KEYCTL_SUPPORTS_VERIFY		0x08
+	__u32		key_size;	/* Size of the key in bits */
+	__u16		max_data_size;	/* Maximum size of raw data to sign in bytes */
+	__u16		max_sig_size;	/* Maximum size of signature in bytes */
+	__u16		max_enc_size;	/* Maximum size of encrypted blob in bytes */
+	__u16		max_dec_size;	/* Maximum size of decrypted blob in bytes */
+	__u32		__spare[10];
+};
+
+struct keyctl_pkey_params {
+	__s32		key_id;		/* Serial no. of public key to use */
+	__s32		password_id;	/* Serial no. of password-containing key to use (or 0) */
+	__u32		data_len;	/* Unencrypted/unsigned data (buffer) size */
+	__u32		enc_len;	/* Encrypted data/signature (buffer) size */
+	__u32		__spare[4];
+};
+
 #endif /*  _LINUX_KEYCTL_H */
diff --git a/security/keys/Makefile b/security/keys/Makefile
index 1fd4a16e6daf..981be73e938f 100644
--- a/security/keys/Makefile
+++ b/security/keys/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_PROC_FS) += proc.o
 obj-$(CONFIG_SYSCTL) += sysctl.o
 obj-$(CONFIG_PERSISTENT_KEYRINGS) += persistent.o
 obj-$(CONFIG_KEY_DH_OPERATIONS) += dh.o
+obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += keyctl_pkey.o
 
 #
 # Key types
diff --git a/security/keys/compat.c b/security/keys/compat.c
index c8783b3b628c..e3e365ebf12d 100644
--- a/security/keys/compat.c
+++ b/security/keys/compat.c
@@ -136,6 +136,17 @@ COMPAT_SYSCALL_DEFINE5(keyctl, u32, option,
 		return keyctl_dh_compute(compat_ptr(arg2), compat_ptr(arg3),
 					 arg4);
 
+	case KEYCTL_PKEY_ENCRYPT:
+	case KEYCTL_PKEY_DECRYPT:
+	case KEYCTL_PKEY_SIGN:
+		return keyctl_pkey_e_d_s(option,
+					 compat_ptr(arg2), compat_ptr(arg3),
+					 compat_ptr(arg4), compat_ptr(arg5));
+
+	case KEYCTL_PKEY_VERIFY:
+		return keyctl_pkey_verify(compat_ptr(arg2), compat_ptr(arg3),
+					  compat_ptr(arg4), compat_ptr(arg5));
+
 	default:
 		return -EOPNOTSUPP;
 	}
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 8ec7a528365d..fba433d91015 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -269,6 +269,41 @@ static inline long keyctl_dh_compute(struct keyctl_dh_params __user *params,
 }
 #endif
 
+#ifdef CONFIG_ASYMMETRIC_KEY_TYPE
+extern long keyctl_pkey_query(key_serial_t,  struct keyctl_pkey_query __user *);
+
+extern long keyctl_pkey_verify(const struct keyctl_pkey_params __user *,
+			       const char __user *,
+			       const void __user *, const void __user *);
+
+extern long keyctl_pkey_e_d_s(int,
+			      const struct keyctl_pkey_params __user *,
+			      const char __user *,
+			      const void __user *, void __user *);
+#else
+static inline long keyctl_pkey_query(key_serial_t id,  struct keyctl_pkey_query __user *_res)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline long keyctl_pkey_verify(const struct keyctl_pkey_params __user *params,
+				      const char __user *_info,
+				      const void __user *_sig,
+				      const void __user *_data)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline long keyctl_pkey_e_d_s(int op,
+				     const struct keyctl_pkey_params __user *params,
+				     const char __user *_info,
+				     const void __user *_in,
+				     void __user *_out)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
 /*
  * Debugging key validation
  */
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 3b135a0af344..bd4580e55eaf 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -1691,6 +1691,27 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3,
 					 (char __user *) arg3,
 					 (size_t) arg4);
 
+	case KEYCTL_PKEY_QUERY:
+		return keyctl_pkey_query((key_serial_t)arg2,
+					 (struct keyctl_pkey_query *)arg3);
+
+	case KEYCTL_PKEY_ENCRYPT:
+	case KEYCTL_PKEY_DECRYPT:
+	case KEYCTL_PKEY_SIGN:
+		return keyctl_pkey_e_d_s(
+			option,
+			(const struct keyctl_pkey_params __user *)arg2,
+			(const char __user *)arg3,
+			(const void __user *)arg4,
+			(void __user *)arg5);
+
+	case KEYCTL_PKEY_VERIFY:
+		return keyctl_pkey_verify(
+			(const struct keyctl_pkey_params __user *)arg2,
+			(const char __user *)arg3,
+			(const void __user *)arg4,
+			(const void __user *)arg5);
+
 	default:
 		return -EOPNOTSUPP;
 	}
diff --git a/security/keys/keyctl_pkey.c b/security/keys/keyctl_pkey.c
new file mode 100644
index 000000000000..c5be02ab0a46
--- /dev/null
+++ b/security/keys/keyctl_pkey.c
@@ -0,0 +1,325 @@
+/* Public-key operation keyctls
+ *
+ * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@xxxxxxxxxx)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/slab.h>
+#include <linux/key.h>
+#include <linux/keyctl.h>
+#include <linux/parser.h>
+#include <crypto/public_key.h>
+#include <keys/asymmetric-type.h>
+#include <keys/user-type.h>
+#include <asm/uaccess.h>
+#include "internal.h"
+
+/*
+ * Query information about an asymmetric key.
+ */
+long keyctl_pkey_query(key_serial_t id,  struct keyctl_pkey_query __user *_res)
+{
+	struct kernel_pkey_query res;
+	struct key *key;
+	key_ref_t key_ref;
+	long ret;
+
+	key_ref = lookup_user_key(id, 0, KEY_NEED_READ);
+	if (IS_ERR(key_ref))
+		return PTR_ERR(key_ref);
+
+	key = key_ref_to_ptr(key_ref);
+
+	ret = query_asymmetric_key(key, &res);
+	if (ret < 0)
+		goto error_key;
+
+	ret = -EFAULT;
+	if (copy_to_user(_res, &res, sizeof(res)) == 0 &&
+	    clear_user(_res->__spare, sizeof(_res->__spare)) == 0)
+		ret = 0;
+
+error_key:
+	key_put(key);
+	return ret;
+}
+
+static void keyctl_pkey_params_free(struct kernel_pkey_params *params)
+{
+	kfree(params->info);
+	key_put(params->key);
+	key_put(params->password);
+}
+
+enum {
+	Opt_err = -1,
+	Opt_enc,		/* "enc=<encoding>" eg. "enc=oaep" */
+	Opt_hash,		/* "hash=<digest-name>" eg. "hash=sha1" */
+};
+
+static const match_table_t param_keys = {
+	{ Opt_enc,	"enc=%s" },
+	{ Opt_hash,	"hash=%s" },
+	{ Opt_err,	NULL }
+};
+
+/*
+ * Parse the information string which consists of key=val pairs.
+ */
+static int keyctl_pkey_params_parse(struct kernel_pkey_params *params)
+{
+	unsigned long token_mask = 0;
+	substring_t args[MAX_OPT_ARGS];
+	char *c = params->info, *p, *q;
+	int token;
+
+	while ((p = strsep(&c, " \t"))) {
+		if (*p == '\0' || *p == ' ' || *p == '\t')
+			continue;
+		token = match_token(p, param_keys, args);
+		if (test_and_set_bit(token, &token_mask))
+			return -EINVAL;
+		q = args[0].from;
+		if (q[0])
+			return -EINVAL;
+
+		switch (token) {
+		case Opt_enc:
+			params->encoding = q;
+			break;
+
+		case Opt_hash:
+			params->hash_algo = q;
+			break;
+
+		default:
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Get parameters from userspace.
+ */
+static int keyctl_pkey_params_get(const struct keyctl_pkey_params __user *_params,
+				  const char __user *_info,
+				  int op,
+				  struct kernel_pkey_params *params)
+{
+	struct keyctl_pkey_params uparams;
+	struct kernel_pkey_query info;
+	key_ref_t key_ref;
+	void *p;
+	int ret;
+
+	memset(params, 0, sizeof(*params));
+	params->encoding = "raw";
+
+	if (copy_from_user(&uparams, _params, sizeof(uparams)) != 0)
+		return -EFAULT;
+
+	p = strndup_user(_info, PAGE_SIZE);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
+	params->info = p;
+
+	ret = keyctl_pkey_params_parse(params);
+
+	key_ref = lookup_user_key(uparams.key_id, 0, KEY_NEED_READ);
+	if (IS_ERR(key_ref))
+		return PTR_ERR(key_ref);
+	params->key = key_ref_to_ptr(key_ref);
+
+	ret = query_asymmetric_key(params->key, &info);
+	if (ret < 0)
+		goto error;
+
+	if (uparams.password_id) {
+		key_ref = lookup_user_key(uparams.password_id, 0,
+					  KEY_NEED_READ);
+		if (IS_ERR(key_ref)) {
+			ret = PTR_ERR(key_ref);
+			goto error;
+		}
+		params->password = key_ref_to_ptr(key_ref);
+		ret = -EINVAL;
+		if (params->password->type != &key_type_logon)
+			goto error;
+	}
+
+	ret = -EINVAL;
+	switch (op) {
+	case KEYCTL_PKEY_ENCRYPT:
+	case KEYCTL_PKEY_DECRYPT:
+		if (uparams.enc_len  > info.max_enc_size ||
+		    uparams.data_len > info.max_dec_size)
+			goto error;
+		break;
+	case KEYCTL_PKEY_SIGN:
+	case KEYCTL_PKEY_VERIFY:
+		if (uparams.enc_len  > info.max_sig_size ||
+		    uparams.data_len > info.max_data_size)
+			goto error;
+		break;
+	default:
+		BUG();
+	}
+
+	params->enc_len  = uparams.enc_len;
+	params->data_len = uparams.data_len;
+	return 0;
+
+error:
+	keyctl_pkey_params_free(params);
+	return ret;
+}
+
+/*
+ * Encrypt/decrypt/sign
+ *
+ * Encrypt data, decrypt data or sign data using a public key.
+ *
+ * _info is a string of supplementary information in key=val format.  For
+ * instance, it might contain:
+ *
+ *	"enc=pkcs1 hash=sha256"
+ *
+ * where enc= specifies the encoding and hash= selects the OID to go in that
+ * particular encoding if required.  If enc= isn't supplied, it's assumed that
+ * the caller is supplying raw values.
+ *
+ * If needed, a password may be provided to unlock the private key in a logon
+ * key whose serial number is in _params->password_id.
+ *
+ * If successful, 0 is returned.
+ */
+long keyctl_pkey_e_d_s(int op,
+		       const struct keyctl_pkey_params __user *_params,
+		       const char __user *_info,
+		       const void __user *_in,
+		       void __user *_out)
+{
+	int (*func)(struct kernel_pkey_params *, const void *, void *);
+	struct kernel_pkey_params params;
+	u16 in_len, out_len;
+	void *in, *out;
+	long ret;
+
+	ret = keyctl_pkey_params_get(_params, _info, op, &params);
+	if (ret < 0)
+		return ret;
+
+	switch (op) {
+	case KEYCTL_PKEY_ENCRYPT:
+		func = encrypt_blob;
+		in_len = params.data_len;
+		out_len = params.enc_len;
+		break;
+	case KEYCTL_PKEY_DECRYPT:
+		func = decrypt_blob;
+		in_len = params.enc_len;
+		out_len = params.data_len;
+		break;
+	case KEYCTL_PKEY_SIGN:
+		func = create_signature;
+		in_len = params.data_len;
+		out_len = params.enc_len;
+		break;
+	default:
+		BUG();
+	}
+
+	in = memdup_user(_in, in_len);
+	if (IS_ERR(in)) {
+		ret = PTR_ERR(in);
+		goto error_params;
+	}
+
+	ret = -ENOMEM;
+	out = kzalloc(out_len, GFP_KERNEL);
+	if (!out)
+		goto error_in;
+
+	ret = func(&params, in, out);
+	if (ret < 0)
+		goto error_out;
+
+	if (copy_to_user(_out, out, out_len) != 0)
+		ret = -EFAULT;
+
+error_out:
+	kfree(out);
+error_in:
+	kfree(in);
+error_params:
+	keyctl_pkey_params_free(&params);
+	return ret;
+}
+
+/*
+ * Verify a signature.
+ *
+ * Verify a public key signature using the given key, or if not given, search
+ * for a matching key.
+ *
+ * _info is a string of supplementary information in key=val format.  For
+ * instance, it might contain:
+ *
+ *	"enc=pkcs1 hash=sha256"
+ *
+ * where enc= specifies the signature blob encoding and hash= selects the OID
+ * to go in that particular encoding.  If enc= isn't supplied, it's assumed
+ * that the caller is supplying raw values.
+ *
+ * If successful, 0 is returned.
+ */
+long keyctl_pkey_verify(const struct keyctl_pkey_params __user *_params,
+			const char __user *_info,
+			const void __user *_sig,
+			const void __user *_data)
+{
+	struct kernel_pkey_params params;
+	struct public_key_signature sig;
+	void *p;
+	long ret;
+
+	ret = keyctl_pkey_params_get(_params, _info, KEYCTL_PKEY_VERIFY,
+				     &params);
+	if (ret < 0)
+		return ret;
+
+	memset(&sig, 0, sizeof(sig));
+	sig.s_size	= params.enc_len;
+	sig.digest_size	= params.data_len;
+	sig.encoding	= params.encoding;
+	sig.hash_algo	= params.hash_algo;
+
+	p = memdup_user(_sig, params.enc_len);
+	if (IS_ERR(p)) {
+		ret = PTR_ERR(p);
+		goto error_params;
+	}
+	sig.s = p;
+
+	p = memdup_user(_data, params.data_len);
+	if (IS_ERR(p)) {
+		ret = PTR_ERR(p);
+		goto error_sig;
+	}
+	sig.digest = p;
+
+	ret = verify_signature(params.key, &sig);
+
+error_sig:
+	public_key_signature_free(&sig);
+error_params:
+	keyctl_pkey_params_free(&params);
+	return ret;
+}
--
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