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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-or-later
 /* Asymmetric public-key cryptography key type
  *
  * See Documentation/crypto/asymmetric-keys.rst
  *
  * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  */
 #include <keys/asymmetric-subtype.h>
 #include <keys/asymmetric-parser.h>
 #include <crypto/public_key.h>
 #include <linux/seq_file.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/ctype.h>
 #include <keys/system_keyring.h>
 #include <keys/user-type.h>
 #include "asymmetric_keys.h"
 
 MODULE_LICENSE("GPL");
 
 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, matched together with @id_0
  * against @keyring keys' id[0] and id[1].
  * @id_2: The fallback ID to match against @keyring keys' id[2] if both of the
  * other IDs are NULL.
  * @partial: Use partial match for @id_0 and @id_1 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
  * former is matched (exactly or partially) against either of the sought key's
  * identifiers and the latter must match the found key's second identifier
  * exactly.  If both are missing, id_2 must match the sought key's third
  * identifier exactly.
  */
 struct key *find_asymmetric_key(struct key *keyring,
                 const struct asymmetric_key_id *id_0,
                 const struct asymmetric_key_id *id_1,
                 const struct asymmetric_key_id *id_2,
                 bool partial)
 {
     struct key *key;
     key_ref_t ref;
     const char *lookup;
     char *req, *p;
     int len;
 
     WARN_ON(!id_0 && !id_1 && !id_2);
 
     if (id_0) {
         lookup = id_0->data;
         len = id_0->len;
     } else if (id_1) {
         lookup = id_1->data;
         len = id_1->len;
     } else {
         lookup = id_2->data;
         len = id_2->len;
     }
 
     /* Construct an identifier "id:<keyid>". */
     p = req = kmalloc(2 + 1 + len * 2 + 1, GFP_KERNEL);
     if (!req)
         return ERR_PTR(-ENOMEM);
 
     if (!id_0 && !id_1) {
         *p++ = 'd';
         *p++ = 'n';
     } else 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, true);
     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);
 
 /**
  * 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.
  * @kid1: The key ID to compare
  * @kid2: The key ID 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
  * @kid1: The key ID to compare
  * @kid2: The key ID 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);
 
 /**
  * asymmetric_match_key_ids - Search asymmetric key IDs 1 & 2
  * @kids: The pair 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 < 2; 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 one of the first two IDs.
  */
 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 one of the first two 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);
 }
 
 /*
  * Match asymmetric keys by an exact match on the third IDs.
  */
 static bool asymmetric_key_cmp_name(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 kids && asymmetric_key_id_same(kids->id[2], match_id);
 }
 
 /*
  * 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 one of the first two IDs
  *  "ex:<id>" - find a key by exact match on one of the first two IDs
  *  "dn:<id>" - find a key by exact match on the third 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 if (spec[0] == 'd' &&
            spec[1] == 'n' &&
            spec[2] == ':') {
         id = spec + 3;
         cmp = asymmetric_key_cmp_name;
     } 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);

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