Imported from linux kernel v5.0.

Signed-off-by: AKASHI Takahiro <takahiro.aka...@linaro.org>
---
 include/crypto/public_key.h    |  89 +++++
 include/keys/asymmetric-type.h |  92 +++++
 lib/crypto/Kconfig             |  19 +
 lib/crypto/Makefile            |  10 +
 lib/crypto/asymmetric_type.c   | 655 +++++++++++++++++++++++++++++++++
 lib/crypto/public_key.c        | 344 +++++++++++++++++
 6 files changed, 1209 insertions(+)
 create mode 100644 include/crypto/public_key.h
 create mode 100644 include/keys/asymmetric-type.h
 create mode 100644 lib/crypto/Kconfig
 create mode 100644 lib/crypto/Makefile
 create mode 100644 lib/crypto/asymmetric_type.c
 create mode 100644 lib/crypto/public_key.c

diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h
new file mode 100644
index 000000000000..91b1f2615294
--- /dev/null
+++ b/include/crypto/public_key.h
@@ -0,0 +1,89 @@
+/* Asymmetric public-key algorithm definitions
+ *
+ * See Documentation/crypto/asymmetric-keys.txt
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowe...@redhat.com)
+ *
+ * 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_PUBLIC_KEY_H
+#define _LINUX_PUBLIC_KEY_H
+
+#ifndef __UBOOT__
+#include <linux/keyctl.h>
+#endif
+#include <linux/types.h>
+
+/*
+ * Cryptographic data for the public-key subtype of the asymmetric key type.
+ *
+ * Note that this may include private part of the key as well as the public
+ * part.
+ */
+struct public_key {
+       void *key;
+       u32 keylen;
+       bool key_is_private;
+       const char *id_type;
+       const char *pkey_algo;
+};
+
+extern void public_key_free(struct public_key *key);
+
+/*
+ * Public key cryptography signature data
+ */
+struct public_key_signature {
+       struct asymmetric_key_id *auth_ids[2];
+       u8 *s;                  /* Signature */
+       u32 s_size;             /* Number of bytes in signature */
+       u8 *digest;
+       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);
+
+#ifndef __UBOOT__
+extern struct asymmetric_key_subtype public_key_subtype;
+
+struct key;
+struct key_type;
+union key_payload;
+
+extern int restrict_link_by_signature(struct key *dest_keyring,
+                                     const struct key_type *type,
+                                     const union key_payload *payload,
+                                     struct key *trust_keyring);
+
+extern int restrict_link_by_key_or_keyring(struct key *dest_keyring,
+                                          const struct key_type *type,
+                                          const union key_payload *payload,
+                                          struct key *trusted);
+
+extern int restrict_link_by_key_or_keyring_chain(struct key *trust_keyring,
+                                                const struct key_type *type,
+                                                const union key_payload 
*payload,
+                                                struct key *trusted);
+
+extern int query_asymmetric_key(const struct kernel_pkey_params *,
+                               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);
+#endif /* !__UBOOT__ */
+
+#endif /* _LINUX_PUBLIC_KEY_H */
diff --git a/include/keys/asymmetric-type.h b/include/keys/asymmetric-type.h
new file mode 100644
index 000000000000..ac34780cd6a4
--- /dev/null
+++ b/include/keys/asymmetric-type.h
@@ -0,0 +1,92 @@
+/* Asymmetric Public-key cryptography key type interface
+ *
+ * See Documentation/crypto/asymmetric-keys.txt
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowe...@redhat.com)
+ *
+ * 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 _KEYS_ASYMMETRIC_TYPE_H
+#define _KEYS_ASYMMETRIC_TYPE_H
+
+#ifndef __UBOOT__
+#include <linux/key-type.h>
+#include <linux/verification.h>
+
+extern struct key_type key_type_asymmetric;
+
+/*
+ * The key payload is four words.  The asymmetric-type key uses them as
+ * follows:
+ */
+enum asymmetric_payload_bits {
+       asym_crypto,            /* The data representing the key */
+       asym_subtype,           /* Pointer to an asymmetric_key_subtype struct 
*/
+       asym_key_ids,           /* Pointer to an asymmetric_key_ids struct */
+       asym_auth               /* The key's authorisation (signature, parent 
key ID) */
+};
+#endif /* !__UBOOT__ */
+
+/*
+ * Identifiers for an asymmetric key ID.  We have three ways of looking up a
+ * key derived from an X.509 certificate:
+ *
+ * (1) Serial Number & Issuer.  Non-optional.  This is the only valid way to
+ *     map a PKCS#7 signature to an X.509 certificate.
+ *
+ * (2) Issuer & Subject Unique IDs.  Optional.  These were the original way to
+ *     match X.509 certificates, but have fallen into disuse in favour of (3).
+ *
+ * (3) Auth & Subject Key Identifiers.  Optional.  SKIDs are only provided on
+ *     CA keys that are intended to sign other keys, so don't appear in end
+ *     user certificates unless forced.
+ *
+ * We could also support an PGP key identifier, which is just a SHA1 sum of the
+ * public key and certain parameters, but since we don't support PGP keys at
+ * the moment, we shall ignore those.
+ *
+ * What we actually do is provide a place where binary identifiers can be
+ * stashed and then compare against them when checking for an id match.
+ */
+struct asymmetric_key_id {
+       unsigned short  len;
+       unsigned char   data[];
+};
+
+struct asymmetric_key_ids {
+       void            *id[2];
+};
+
+extern bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1,
+                                  const struct asymmetric_key_id *kid2);
+
+extern bool asymmetric_key_id_partial(const struct asymmetric_key_id *kid1,
+                                     const struct asymmetric_key_id *kid2);
+
+extern struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1,
+                                                           size_t len_1,
+                                                           const void *val_2,
+                                                           size_t len_2);
+#ifndef __UBOOT__
+static inline
+const struct asymmetric_key_ids *asymmetric_key_ids(const struct key *key)
+{
+       return key->payload.data[asym_key_ids];
+}
+
+extern struct key *find_asymmetric_key(struct key *keyring,
+                                      const struct asymmetric_key_id *id_0,
+                                      const struct asymmetric_key_id *id_1,
+                                      bool partial);
+#endif
+
+/*
+ * The payload is at the discretion of the subtype.
+ */
+
+#endif /* _KEYS_ASYMMETRIC_TYPE_H */
diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig
new file mode 100644
index 000000000000..b8e8288d2f80
--- /dev/null
+++ b/lib/crypto/Kconfig
@@ -0,0 +1,19 @@
+menuconfig ASYMMETRIC_KEY_TYPE
+       bool "Asymmetric (public-key cryptographic) key Support"
+       help
+         This option provides support for a key type that holds the data for
+         the asymmetric keys used for public key cryptographic operations such
+         as encryption, decryption, signature generation and signature
+         verification.
+
+if ASYMMETRIC_KEY_TYPE
+
+config ASYMMETRIC_PUBLIC_KEY_SUBTYPE
+       bool "Asymmetric public-key crypto algorithm subtype"
+       help
+         This option provides support for asymmetric public key type handling.
+         If signature generation and/or verification are to be used,
+         appropriate hash algorithms (such as SHA-1) must be available.
+         ENOPKG will be reported if the requisite algorithm is unavailable.
+
+endif # ASYMMETRIC_KEY_TYPE
diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile
new file mode 100644
index 000000000000..a284de9e0411
--- /dev/null
+++ b/lib/crypto/Makefile
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Makefile for asymmetric cryptographic keys
+#
+
+obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o
+
+asymmetric_keys-y := asymmetric_type.o
+
+obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o
diff --git a/lib/crypto/asymmetric_type.c b/lib/crypto/asymmetric_type.c
new file mode 100644
index 000000000000..905e8b490133
--- /dev/null
+++ b/lib/crypto/asymmetric_type.c
@@ -0,0 +1,655 @@
+/* Asymmetric public-key cryptography key type
+ *
+ * See Documentation/crypto/asymmetric-keys.txt
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowe...@redhat.com)
+ *
+ * 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 <crypto/public_key.h>
+#include <linux/compat.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <keys/asymmetric-type.h>
+
+MODULE_LICENSE("GPL");
+
+#ifndef __UBOOT__
+const char *const key_being_used_for[NR__KEY_BEING_USED_FOR] = {
+       [VERIFYING_MODULE_SIGNATURE]            = "mod sig",
+       [VERIFYING_FIRMWARE_SIGNATURE]          = "firmware sig",
+       [VERIFYING_KEXEC_PE_SIGNATURE]          = "kexec PE sig",
+       [VERIFYING_KEY_SIGNATURE]               = "key sig",
+       [VERIFYING_KEY_SELF_SIGNATURE]          = "key self sig",
+       [VERIFYING_UNSPECIFIED_SIGNATURE]       = "unspec sig",
+};
+EXPORT_SYMBOL_GPL(key_being_used_for);
+
+static LIST_HEAD(asymmetric_key_parsers);
+static DECLARE_RWSEM(asymmetric_key_parsers_sem);
+
+/**
+ * find_asymmetric_key - Find a key by ID.
+ * @keyring: The keys to search.
+ * @id_0: The first ID to look for or NULL.
+ * @id_1: The second ID to look for or NULL.
+ * @partial: Use partial match if true, exact if false.
+ *
+ * Find a key in the given keyring by identifier.  The preferred identifier is
+ * the id_0 and the fallback identifier is the id_1.  If both are given, the
+ * lookup is by the former, but the latter must also match.
+ */
+struct key *find_asymmetric_key(struct key *keyring,
+                               const struct asymmetric_key_id *id_0,
+                               const struct asymmetric_key_id *id_1,
+                               bool partial)
+{
+       struct key *key;
+       key_ref_t ref;
+       const char *lookup;
+       char *req, *p;
+       int len;
+
+       BUG_ON(!id_0 && !id_1);
+
+       if (id_0) {
+               lookup = id_0->data;
+               len = id_0->len;
+       } else {
+               lookup = id_1->data;
+               len = id_1->len;
+       }
+
+       /* Construct an identifier "id:<keyid>". */
+       p = req = kmalloc(2 + 1 + len * 2 + 1, GFP_KERNEL);
+       if (!req)
+               return ERR_PTR(-ENOMEM);
+
+       if (partial) {
+               *p++ = 'i';
+               *p++ = 'd';
+       } else {
+               *p++ = 'e';
+               *p++ = 'x';
+       }
+       *p++ = ':';
+       p = bin2hex(p, lookup, len);
+       *p = 0;
+
+       pr_debug("Look up: \"%s\"\n", req);
+
+       ref = keyring_search(make_key_ref(keyring, 1),
+                            &key_type_asymmetric, req);
+       if (IS_ERR(ref))
+               pr_debug("Request for key '%s' err %ld\n", req, PTR_ERR(ref));
+       kfree(req);
+
+       if (IS_ERR(ref)) {
+               switch (PTR_ERR(ref)) {
+                       /* Hide some search errors */
+               case -EACCES:
+               case -ENOTDIR:
+               case -EAGAIN:
+                       return ERR_PTR(-ENOKEY);
+               default:
+                       return ERR_CAST(ref);
+               }
+       }
+
+       key = key_ref_to_ptr(ref);
+       if (id_0 && id_1) {
+               const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
+
+               if (!kids->id[1]) {
+                       pr_debug("First ID matches, but second is missing\n");
+                       goto reject;
+               }
+               if (!asymmetric_key_id_same(id_1, kids->id[1])) {
+                       pr_debug("First ID matches, but second does not\n");
+                       goto reject;
+               }
+       }
+
+       pr_devel("<==%s() = 0 [%x]\n", __func__, key_serial(key));
+       return key;
+
+reject:
+       key_put(key);
+       return ERR_PTR(-EKEYREJECTED);
+}
+EXPORT_SYMBOL_GPL(find_asymmetric_key);
+#endif /* !__UBOOT__ */
+
+/**
+ * asymmetric_key_generate_id: Construct an asymmetric key ID
+ * @val_1: First binary blob
+ * @len_1: Length of first binary blob
+ * @val_2: Second binary blob
+ * @len_2: Length of second binary blob
+ *
+ * Construct an asymmetric key ID from a pair of binary blobs.
+ */
+struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1,
+                                                    size_t len_1,
+                                                    const void *val_2,
+                                                    size_t len_2)
+{
+       struct asymmetric_key_id *kid;
+
+       kid = kmalloc(sizeof(struct asymmetric_key_id) + len_1 + len_2,
+                     GFP_KERNEL);
+       if (!kid)
+               return ERR_PTR(-ENOMEM);
+       kid->len = len_1 + len_2;
+       memcpy(kid->data, val_1, len_1);
+       memcpy(kid->data + len_1, val_2, len_2);
+       return kid;
+}
+EXPORT_SYMBOL_GPL(asymmetric_key_generate_id);
+
+/**
+ * asymmetric_key_id_same - Return true if two asymmetric keys IDs are the 
same.
+ * @kid_1, @kid_2: The key IDs to compare
+ */
+bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1,
+                           const struct asymmetric_key_id *kid2)
+{
+       if (!kid1 || !kid2)
+               return false;
+       if (kid1->len != kid2->len)
+               return false;
+       return memcmp(kid1->data, kid2->data, kid1->len) == 0;
+}
+EXPORT_SYMBOL_GPL(asymmetric_key_id_same);
+
+/**
+ * asymmetric_key_id_partial - Return true if two asymmetric keys IDs
+ * partially match
+ * @kid_1, @kid_2: The key IDs to compare
+ */
+bool asymmetric_key_id_partial(const struct asymmetric_key_id *kid1,
+                              const struct asymmetric_key_id *kid2)
+{
+       if (!kid1 || !kid2)
+               return false;
+       if (kid1->len < kid2->len)
+               return false;
+       return memcmp(kid1->data + (kid1->len - kid2->len),
+                     kid2->data, kid2->len) == 0;
+}
+EXPORT_SYMBOL_GPL(asymmetric_key_id_partial);
+
+#ifndef __UBOOT__
+/**
+ * asymmetric_match_key_ids - Search asymmetric key IDs
+ * @kids: The list of key IDs to check
+ * @match_id: The key ID we're looking for
+ * @match: The match function to use
+ */
+static bool asymmetric_match_key_ids(
+       const struct asymmetric_key_ids *kids,
+       const struct asymmetric_key_id *match_id,
+       bool (*match)(const struct asymmetric_key_id *kid1,
+                     const struct asymmetric_key_id *kid2))
+{
+       int i;
+
+       if (!kids || !match_id)
+               return false;
+       for (i = 0; i < ARRAY_SIZE(kids->id); i++)
+               if (match(kids->id[i], match_id))
+                       return true;
+       return false;
+}
+
+/* helper function can be called directly with pre-allocated memory */
+inline int __asymmetric_key_hex_to_key_id(const char *id,
+                                  struct asymmetric_key_id *match_id,
+                                  size_t hexlen)
+{
+       match_id->len = hexlen;
+       return hex2bin(match_id->data, id, hexlen);
+}
+
+/**
+ * asymmetric_key_hex_to_key_id - Convert a hex string into a key ID.
+ * @id: The ID as a hex string.
+ */
+struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id)
+{
+       struct asymmetric_key_id *match_id;
+       size_t asciihexlen;
+       int ret;
+
+       if (!*id)
+               return ERR_PTR(-EINVAL);
+       asciihexlen = strlen(id);
+       if (asciihexlen & 1)
+               return ERR_PTR(-EINVAL);
+
+       match_id = kmalloc(sizeof(struct asymmetric_key_id) + asciihexlen / 2,
+                          GFP_KERNEL);
+       if (!match_id)
+               return ERR_PTR(-ENOMEM);
+       ret = __asymmetric_key_hex_to_key_id(id, match_id, asciihexlen / 2);
+       if (ret < 0) {
+               kfree(match_id);
+               return ERR_PTR(-EINVAL);
+       }
+       return match_id;
+}
+
+/*
+ * Match asymmetric keys by an exact match on an ID.
+ */
+static bool asymmetric_key_cmp(const struct key *key,
+                              const struct key_match_data *match_data)
+{
+       const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
+       const struct asymmetric_key_id *match_id = match_data->preparsed;
+
+       return asymmetric_match_key_ids(kids, match_id,
+                                       asymmetric_key_id_same);
+}
+
+/*
+ * Match asymmetric keys by a partial match on an IDs.
+ */
+static bool asymmetric_key_cmp_partial(const struct key *key,
+                                      const struct key_match_data *match_data)
+{
+       const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
+       const struct asymmetric_key_id *match_id = match_data->preparsed;
+
+       return asymmetric_match_key_ids(kids, match_id,
+                                       asymmetric_key_id_partial);
+}
+
+/*
+ * Preparse the match criterion.  If we don't set lookup_type and cmp,
+ * the default will be an exact match on the key description.
+ *
+ * There are some specifiers for matching key IDs rather than by the key
+ * description:
+ *
+ *     "id:<id>" - find a key by partial match on any available ID
+ *     "ex:<id>" - find a key by exact match on any available ID
+ *
+ * These have to be searched by iteration rather than by direct lookup because
+ * the key is hashed according to its description.
+ */
+static int asymmetric_key_match_preparse(struct key_match_data *match_data)
+{
+       struct asymmetric_key_id *match_id;
+       const char *spec = match_data->raw_data;
+       const char *id;
+       bool (*cmp)(const struct key *, const struct key_match_data *) =
+               asymmetric_key_cmp;
+
+       if (!spec || !*spec)
+               return -EINVAL;
+       if (spec[0] == 'i' &&
+           spec[1] == 'd' &&
+           spec[2] == ':') {
+               id = spec + 3;
+               cmp = asymmetric_key_cmp_partial;
+       } else if (spec[0] == 'e' &&
+                  spec[1] == 'x' &&
+                  spec[2] == ':') {
+               id = spec + 3;
+       } else {
+               goto default_match;
+       }
+
+       match_id = asymmetric_key_hex_to_key_id(id);
+       if (IS_ERR(match_id))
+               return PTR_ERR(match_id);
+
+       match_data->preparsed = match_id;
+       match_data->cmp = cmp;
+       match_data->lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE;
+       return 0;
+
+default_match:
+       return 0;
+}
+
+/*
+ * Free the preparsed the match criterion.
+ */
+static void asymmetric_key_match_free(struct key_match_data *match_data)
+{
+       kfree(match_data->preparsed);
+}
+
+/*
+ * Describe the asymmetric key
+ */
+static void asymmetric_key_describe(const struct key *key, struct seq_file *m)
+{
+       const struct asymmetric_key_subtype *subtype = 
asymmetric_key_subtype(key);
+       const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
+       const struct asymmetric_key_id *kid;
+       const unsigned char *p;
+       int n;
+
+       seq_puts(m, key->description);
+
+       if (subtype) {
+               seq_puts(m, ": ");
+               subtype->describe(key, m);
+
+               if (kids && kids->id[1]) {
+                       kid = kids->id[1];
+                       seq_putc(m, ' ');
+                       n = kid->len;
+                       p = kid->data;
+                       if (n > 4) {
+                               p += n - 4;
+                               n = 4;
+                       }
+                       seq_printf(m, "%*phN", n, p);
+               }
+
+               seq_puts(m, " [");
+               /* put something here to indicate the key's capabilities */
+               seq_putc(m, ']');
+       }
+}
+
+/*
+ * Preparse a asymmetric payload to get format the contents appropriately for 
the
+ * internal payload to cut down on the number of scans of the data performed.
+ *
+ * We also generate a proposed description from the contents of the key that
+ * can be used to name the key if the user doesn't want to provide one.
+ */
+static int asymmetric_key_preparse(struct key_preparsed_payload *prep)
+{
+       struct asymmetric_key_parser *parser;
+       int ret;
+
+       pr_devel("==>%s()\n", __func__);
+
+       if (prep->datalen == 0)
+               return -EINVAL;
+
+       down_read(&asymmetric_key_parsers_sem);
+
+       ret = -EBADMSG;
+       list_for_each_entry(parser, &asymmetric_key_parsers, link) {
+               pr_debug("Trying parser '%s'\n", parser->name);
+
+               ret = parser->parse(prep);
+               if (ret != -EBADMSG) {
+                       pr_debug("Parser recognised the format (ret %d)\n",
+                                ret);
+                       break;
+               }
+       }
+
+       up_read(&asymmetric_key_parsers_sem);
+       pr_devel("<==%s() = %d\n", __func__, ret);
+       return ret;
+}
+
+/*
+ * Clean up the key ID list
+ */
+static void asymmetric_key_free_kids(struct asymmetric_key_ids *kids)
+{
+       int i;
+
+       if (kids) {
+               for (i = 0; i < ARRAY_SIZE(kids->id); i++)
+                       kfree(kids->id[i]);
+               kfree(kids);
+       }
+}
+
+/*
+ * Clean up the preparse data
+ */
+static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep)
+{
+       struct asymmetric_key_subtype *subtype = 
prep->payload.data[asym_subtype];
+       struct asymmetric_key_ids *kids = prep->payload.data[asym_key_ids];
+
+       pr_devel("==>%s()\n", __func__);
+
+       if (subtype) {
+               subtype->destroy(prep->payload.data[asym_crypto],
+                                prep->payload.data[asym_auth]);
+               module_put(subtype->owner);
+       }
+       asymmetric_key_free_kids(kids);
+       kfree(prep->description);
+}
+
+/*
+ * dispose of the data dangling from the corpse of a asymmetric key
+ */
+static void asymmetric_key_destroy(struct key *key)
+{
+       struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
+       struct asymmetric_key_ids *kids = key->payload.data[asym_key_ids];
+       void *data = key->payload.data[asym_crypto];
+       void *auth = key->payload.data[asym_auth];
+
+       key->payload.data[asym_crypto] = NULL;
+       key->payload.data[asym_subtype] = NULL;
+       key->payload.data[asym_key_ids] = NULL;
+       key->payload.data[asym_auth] = NULL;
+
+       if (subtype) {
+               subtype->destroy(data, auth);
+               module_put(subtype->owner);
+       }
+
+       asymmetric_key_free_kids(kids);
+}
+
+static struct key_restriction *asymmetric_restriction_alloc(
+       key_restrict_link_func_t check,
+       struct key *key)
+{
+       struct key_restriction *keyres =
+               kzalloc(sizeof(struct key_restriction), GFP_KERNEL);
+
+       if (!keyres)
+               return ERR_PTR(-ENOMEM);
+
+       keyres->check = check;
+       keyres->key = key;
+       keyres->keytype = &key_type_asymmetric;
+
+       return keyres;
+}
+
+/*
+ * look up keyring restrict functions for asymmetric keys
+ */
+static struct key_restriction *asymmetric_lookup_restriction(
+       const char *restriction)
+{
+       char *restrict_method;
+       char *parse_buf;
+       char *next;
+       struct key_restriction *ret = ERR_PTR(-EINVAL);
+
+       if (strcmp("builtin_trusted", restriction) == 0)
+               return asymmetric_restriction_alloc(
+                       restrict_link_by_builtin_trusted, NULL);
+
+       if (strcmp("builtin_and_secondary_trusted", restriction) == 0)
+               return asymmetric_restriction_alloc(
+                       restrict_link_by_builtin_and_secondary_trusted, NULL);
+
+       parse_buf = kstrndup(restriction, PAGE_SIZE, GFP_KERNEL);
+       if (!parse_buf)
+               return ERR_PTR(-ENOMEM);
+
+       next = parse_buf;
+       restrict_method = strsep(&next, ":");
+
+       if ((strcmp(restrict_method, "key_or_keyring") == 0) && next) {
+               char *key_text;
+               key_serial_t serial;
+               struct key *key;
+               key_restrict_link_func_t link_fn =
+                       restrict_link_by_key_or_keyring;
+               bool allow_null_key = false;
+
+               key_text = strsep(&next, ":");
+
+               if (next) {
+                       if (strcmp(next, "chain") != 0)
+                               goto out;
+
+                       link_fn = restrict_link_by_key_or_keyring_chain;
+                       allow_null_key = true;
+               }
+
+               if (kstrtos32(key_text, 0, &serial) < 0)
+                       goto out;
+
+               if ((serial == 0) && allow_null_key) {
+                       key = NULL;
+               } else {
+                       key = key_lookup(serial);
+                       if (IS_ERR(key)) {
+                               ret = ERR_CAST(key);
+                               goto out;
+                       }
+               }
+
+               ret = asymmetric_restriction_alloc(link_fn, key);
+               if (IS_ERR(ret))
+                       key_put(key);
+       }
+
+out:
+       kfree(parse_buf);
+       return ret;
+}
+
+int asymmetric_key_eds_op(struct kernel_pkey_params *params,
+                         const void *in, void *out)
+{
+       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->eds_op)
+               return -ENOTSUPP;
+
+       ret = subtype->eds_op(params, in, out);
+
+       pr_devel("<==%s() = %d\n", __func__, ret);
+       return ret;
+}
+
+static int asymmetric_key_verify_signature(struct kernel_pkey_params *params,
+                                          const void *in, const void *in2)
+{
+       struct public_key_signature sig = {
+               .s_size         = params->in2_len,
+               .digest_size    = params->in_len,
+               .encoding       = params->encoding,
+               .hash_algo      = params->hash_algo,
+               .digest         = (void *)in,
+               .s              = (void *)in2,
+       };
+
+       return verify_signature(params->key, &sig);
+}
+
+struct key_type key_type_asymmetric = {
+       .name                   = "asymmetric",
+       .preparse               = asymmetric_key_preparse,
+       .free_preparse          = asymmetric_key_free_preparse,
+       .instantiate            = generic_key_instantiate,
+       .match_preparse         = asymmetric_key_match_preparse,
+       .match_free             = asymmetric_key_match_free,
+       .destroy                = asymmetric_key_destroy,
+       .describe               = asymmetric_key_describe,
+       .lookup_restriction     = asymmetric_lookup_restriction,
+       .asym_query             = query_asymmetric_key,
+       .asym_eds_op            = asymmetric_key_eds_op,
+       .asym_verify_signature  = asymmetric_key_verify_signature,
+};
+EXPORT_SYMBOL_GPL(key_type_asymmetric);
+
+/**
+ * register_asymmetric_key_parser - Register a asymmetric key blob parser
+ * @parser: The parser to register
+ */
+int register_asymmetric_key_parser(struct asymmetric_key_parser *parser)
+{
+       struct asymmetric_key_parser *cursor;
+       int ret;
+
+       down_write(&asymmetric_key_parsers_sem);
+
+       list_for_each_entry(cursor, &asymmetric_key_parsers, link) {
+               if (strcmp(cursor->name, parser->name) == 0) {
+                       pr_err("Asymmetric key parser '%s' already 
registered\n",
+                              parser->name);
+                       ret = -EEXIST;
+                       goto out;
+               }
+       }
+
+       list_add_tail(&parser->link, &asymmetric_key_parsers);
+
+       pr_notice("Asymmetric key parser '%s' registered\n", parser->name);
+       ret = 0;
+
+out:
+       up_write(&asymmetric_key_parsers_sem);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(register_asymmetric_key_parser);
+
+/**
+ * unregister_asymmetric_key_parser - Unregister a asymmetric key blob parser
+ * @parser: The parser to unregister
+ */
+void unregister_asymmetric_key_parser(struct asymmetric_key_parser *parser)
+{
+       down_write(&asymmetric_key_parsers_sem);
+       list_del(&parser->link);
+       up_write(&asymmetric_key_parsers_sem);
+
+       pr_notice("Asymmetric key parser '%s' unregistered\n", parser->name);
+}
+EXPORT_SYMBOL_GPL(unregister_asymmetric_key_parser);
+
+/*
+ * Module stuff
+ */
+static int __init asymmetric_key_init(void)
+{
+       return register_key_type(&key_type_asymmetric);
+}
+
+static void __exit asymmetric_key_cleanup(void)
+{
+       unregister_key_type(&key_type_asymmetric);
+}
+
+module_init(asymmetric_key_init);
+module_exit(asymmetric_key_cleanup);
+#endif /* !__UBOOT__ */
diff --git a/lib/crypto/public_key.c b/lib/crypto/public_key.c
new file mode 100644
index 000000000000..c48f777b06b4
--- /dev/null
+++ b/lib/crypto/public_key.c
@@ -0,0 +1,344 @@
+/* In-software asymmetric public-key crypto subtype
+ *
+ * See Documentation/crypto/asymmetric-keys.txt
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowe...@redhat.com)
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt) "PKEY: "fmt
+#include <linux/compat.h>
+#include <linux/kernel.h>
+#include <crypto/public_key.h>
+
+MODULE_DESCRIPTION("In-software asymmetric public-key subtype");
+MODULE_AUTHOR("Red Hat, Inc.");
+MODULE_LICENSE("GPL");
+
+#ifndef __UBOOT__
+/*
+ * Provide a part of a description of the key for /proc/keys.
+ */
+static void public_key_describe(const struct key *asymmetric_key,
+                               struct seq_file *m)
+{
+       struct public_key *key = asymmetric_key->payload.data[asym_crypto];
+
+       if (key)
+               seq_printf(m, "%s.%s", key->id_type, key->pkey_algo);
+}
+#endif
+
+/*
+ * Destroy a public key algorithm key.
+ */
+void public_key_free(struct public_key *key)
+{
+       if (key) {
+               kfree(key->key);
+               kfree(key);
+       }
+}
+EXPORT_SYMBOL_GPL(public_key_free);
+
+/*
+ * from <linux>/crypto/asymmetric_keys/signature.c
+ *
+ * Destroy a public key signature.
+ */
+void public_key_signature_free(struct public_key_signature *sig)
+{
+       int i;
+
+       if (sig) {
+               for (i = 0; i < ARRAY_SIZE(sig->auth_ids); i++)
+                       free(sig->auth_ids[i]);
+               free(sig->s);
+               free(sig->digest);
+               free(sig);
+       }
+}
+EXPORT_SYMBOL_GPL(public_key_signature_free);
+
+#ifndef __UBOOT__
+/*
+ * Destroy a public key algorithm key.
+ */
+static void public_key_destroy(void *payload0, void *payload3)
+{
+       public_key_free(payload0);
+       public_key_signature_free(payload3);
+}
+
+/*
+ * Determine the crypto algorithm name.
+ */
+static
+int software_key_determine_akcipher(const char *encoding,
+                                   const char *hash_algo,
+                                   const struct public_key *pkey,
+                                   char alg_name[CRYPTO_MAX_ALG_NAME])
+{
+       int n;
+
+       if (strcmp(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].
+                */
+               if (!hash_algo)
+                       n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
+                                    "pkcs1pad(%s)",
+                                    pkey->pkey_algo);
+               else
+                       n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
+                                    "pkcs1pad(%s,%s)",
+                                    pkey->pkey_algo, hash_algo);
+               return n >= CRYPTO_MAX_ALG_NAME ? -EINVAL : 0;
+       }
+
+       if (strcmp(encoding, "raw") == 0) {
+               strcpy(alg_name, pkey->pkey_algo);
+               return 0;
+       }
+
+       return -ENOPKG;
+}
+
+/*
+ * Query information about a key.
+ */
+static int software_key_query(const struct kernel_pkey_params *params,
+                             struct kernel_pkey_query *info)
+{
+       struct crypto_akcipher *tfm;
+       struct public_key *pkey = params->key->payload.data[asym_crypto];
+       char alg_name[CRYPTO_MAX_ALG_NAME];
+       int ret, len;
+
+       ret = software_key_determine_akcipher(params->encoding,
+                                             params->hash_algo,
+                                             pkey, alg_name);
+       if (ret < 0)
+               return ret;
+
+       tfm = crypto_alloc_akcipher(alg_name, 0, 0);
+       if (IS_ERR(tfm))
+               return PTR_ERR(tfm);
+
+       if (pkey->key_is_private)
+               ret = crypto_akcipher_set_priv_key(tfm,
+                                                  pkey->key, pkey->keylen);
+       else
+               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_ENCRYPT |
+                              KEYCTL_SUPPORTS_VERIFY);
+       if (pkey->key_is_private)
+               info->supported_ops |= (KEYCTL_SUPPORTS_DECRYPT |
+                                       KEYCTL_SUPPORTS_SIGN);
+       ret = 0;
+
+error_free_tfm:
+       crypto_free_akcipher(tfm);
+       pr_devel("<==%s() = %d\n", __func__, ret);
+       return ret;
+}
+
+/*
+ * Do encryption, decryption and signing ops.
+ */
+static int software_key_eds_op(struct kernel_pkey_params *params,
+                              const void *in, void *out)
+{
+       const struct public_key *pkey = params->key->payload.data[asym_crypto];
+       struct akcipher_request *req;
+       struct crypto_akcipher *tfm;
+       struct crypto_wait cwait;
+       struct scatterlist in_sg, out_sg;
+       char alg_name[CRYPTO_MAX_ALG_NAME];
+       int ret;
+
+       pr_devel("==>%s()\n", __func__);
+
+       ret = software_key_determine_akcipher(params->encoding,
+                                             params->hash_algo,
+                                             pkey, alg_name);
+       if (ret < 0)
+               return ret;
+
+       tfm = crypto_alloc_akcipher(alg_name, 0, 0);
+       if (IS_ERR(tfm))
+               return PTR_ERR(tfm);
+
+       req = akcipher_request_alloc(tfm, GFP_KERNEL);
+       if (!req)
+               goto error_free_tfm;
+
+       if (pkey->key_is_private)
+               ret = crypto_akcipher_set_priv_key(tfm,
+                                                  pkey->key, pkey->keylen);
+       else
+               ret = crypto_akcipher_set_pub_key(tfm,
+                                                 pkey->key, pkey->keylen);
+       if (ret)
+               goto error_free_req;
+
+       sg_init_one(&in_sg, in, params->in_len);
+       sg_init_one(&out_sg, out, params->out_len);
+       akcipher_request_set_crypt(req, &in_sg, &out_sg, params->in_len,
+                                  params->out_len);
+       crypto_init_wait(&cwait);
+       akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
+                                     CRYPTO_TFM_REQ_MAY_SLEEP,
+                                     crypto_req_done, &cwait);
+
+       /* Perform the encryption calculation. */
+       switch (params->op) {
+       case kernel_pkey_encrypt:
+               ret = crypto_akcipher_encrypt(req);
+               break;
+       case kernel_pkey_decrypt:
+               ret = crypto_akcipher_decrypt(req);
+               break;
+       case kernel_pkey_sign:
+               ret = crypto_akcipher_sign(req);
+               break;
+       default:
+               BUG();
+       }
+
+       ret = crypto_wait_req(ret, &cwait);
+       if (ret == 0)
+               ret = req->dst_len;
+
+error_free_req:
+       akcipher_request_free(req);
+error_free_tfm:
+       crypto_free_akcipher(tfm);
+       pr_devel("<==%s() = %d\n", __func__, ret);
+       return ret;
+}
+
+/*
+ * Verify a signature using a public key.
+ */
+int public_key_verify_signature(const struct public_key *pkey,
+                               const struct public_key_signature *sig)
+{
+       struct crypto_wait cwait;
+       struct crypto_akcipher *tfm;
+       struct akcipher_request *req;
+       struct scatterlist sig_sg, digest_sg;
+       char alg_name[CRYPTO_MAX_ALG_NAME];
+       void *output;
+       unsigned int outlen;
+       int ret;
+
+       pr_devel("==>%s()\n", __func__);
+
+       BUG_ON(!pkey);
+       BUG_ON(!sig);
+       BUG_ON(!sig->s);
+
+       ret = software_key_determine_akcipher(sig->encoding,
+                                             sig->hash_algo,
+                                             pkey, alg_name);
+       if (ret < 0)
+               return ret;
+
+       tfm = crypto_alloc_akcipher(alg_name, 0, 0);
+       if (IS_ERR(tfm))
+               return PTR_ERR(tfm);
+
+       ret = -ENOMEM;
+       req = akcipher_request_alloc(tfm, GFP_KERNEL);
+       if (!req)
+               goto error_free_tfm;
+
+       if (pkey->key_is_private)
+               ret = crypto_akcipher_set_priv_key(tfm,
+                                                  pkey->key, pkey->keylen);
+       else
+               ret = crypto_akcipher_set_pub_key(tfm,
+                                                 pkey->key, pkey->keylen);
+       if (ret)
+               goto error_free_req;
+
+       ret = -ENOMEM;
+       outlen = crypto_akcipher_maxsize(tfm);
+       output = kmalloc(outlen, GFP_KERNEL);
+       if (!output)
+               goto error_free_req;
+
+       sg_init_one(&sig_sg, sig->s, sig->s_size);
+       sg_init_one(&digest_sg, output, outlen);
+       akcipher_request_set_crypt(req, &sig_sg, &digest_sg, sig->s_size,
+                                  outlen);
+       crypto_init_wait(&cwait);
+       akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
+                                     CRYPTO_TFM_REQ_MAY_SLEEP,
+                                     crypto_req_done, &cwait);
+
+       /* Perform the verification calculation.  This doesn't actually do the
+        * verification, but rather calculates the hash expected by the
+        * signature and returns that to us.
+        */
+       ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
+       if (ret)
+               goto out_free_output;
+
+       /* Do the actual verification step. */
+       if (req->dst_len != sig->digest_size ||
+           memcmp(sig->digest, output, sig->digest_size) != 0)
+               ret = -EKEYREJECTED;
+
+out_free_output:
+       kfree(output);
+error_free_req:
+       akcipher_request_free(req);
+error_free_tfm:
+       crypto_free_akcipher(tfm);
+       pr_devel("<==%s() = %d\n", __func__, ret);
+       if (WARN_ON_ONCE(ret > 0))
+               ret = -EINVAL;
+       return ret;
+}
+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[asym_crypto];
+       return public_key_verify_signature(pk, sig);
+}
+
+/*
+ * Public key algorithm asymmetric key subtype
+ */
+struct asymmetric_key_subtype public_key_subtype = {
+       .owner                  = THIS_MODULE,
+       .name                   = "public_key",
+       .name_len               = sizeof("public_key") - 1,
+       .describe               = public_key_describe,
+       .destroy                = public_key_destroy,
+       .query                  = software_key_query,
+       .eds_op                 = software_key_eds_op,
+       .verify_signature       = public_key_verify_signature_2,
+};
+EXPORT_SYMBOL_GPL(public_key_subtype);
+#endif /* !__UBOOT__ */
-- 
2.21.0

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