| /* Definitions for key type implementations |
| * |
| * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. |
| * Written by David Howells (dhowells@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_KEY_TYPE_H |
| #define _LINUX_KEY_TYPE_H |
| |
| #include <linux/key.h> |
| #include <linux/errno.h> |
| |
| #ifdef CONFIG_KEYS |
| |
| /* |
| * key under-construction record |
| * - passed to the request_key actor if supplied |
| */ |
| struct key_construction { |
| struct key *key; /* key being constructed */ |
| struct key *authkey;/* authorisation for key being constructed */ |
| }; |
| |
| /* |
| * Pre-parsed payload, used by key add, update and instantiate. |
| * |
| * This struct will be cleared and data and datalen will be set with the data |
| * and length parameters from the caller and quotalen will be set from |
| * def_datalen from the key type. Then if the preparse() op is provided by the |
| * key type, that will be called. Then the struct will be passed to the |
| * instantiate() or the update() op. |
| * |
| * If the preparse() op is given, the free_preparse() op will be called to |
| * clear the contents. |
| */ |
| struct key_preparsed_payload { |
| char *description; /* Proposed key description (or NULL) */ |
| union key_payload payload; /* Proposed payload */ |
| const void *data; /* Raw data */ |
| size_t datalen; /* Raw datalen */ |
| size_t quotalen; /* Quota length for proposed payload */ |
| time_t expiry; /* Expiry time of key */ |
| } __randomize_layout; |
| |
| typedef int (*request_key_actor_t)(struct key_construction *key, |
| const char *op, void *aux); |
| |
| /* |
| * Preparsed matching criterion. |
| */ |
| struct key_match_data { |
| /* Comparison function, defaults to exact description match, but can be |
| * overridden by type->match_preparse(). Should return true if a match |
| * is found and false if not. |
| */ |
| bool (*cmp)(const struct key *key, |
| const struct key_match_data *match_data); |
| |
| const void *raw_data; /* Raw match data */ |
| void *preparsed; /* For ->match_preparse() to stash stuff */ |
| unsigned lookup_type; /* Type of lookup for this search. */ |
| #define KEYRING_SEARCH_LOOKUP_DIRECT 0x0000 /* Direct lookup by description. */ |
| #define KEYRING_SEARCH_LOOKUP_ITERATE 0x0001 /* Iterative search. */ |
| }; |
| |
| /* |
| * kernel managed key type definition |
| */ |
| struct key_type { |
| /* name of the type */ |
| const char *name; |
| |
| /* default payload length for quota precalculation (optional) |
| * - this can be used instead of calling key_payload_reserve(), that |
| * function only needs to be called if the real datalen is different |
| */ |
| size_t def_datalen; |
| |
| /* vet a description */ |
| int (*vet_description)(const char *description); |
| |
| /* Preparse the data blob from userspace that is to be the payload, |
| * generating a proposed description and payload that will be handed to |
| * the instantiate() and update() ops. |
| */ |
| int (*preparse)(struct key_preparsed_payload *prep); |
| |
| /* Free a preparse data structure. |
| */ |
| void (*free_preparse)(struct key_preparsed_payload *prep); |
| |
| /* instantiate a key of this type |
| * - this method should call key_payload_reserve() to determine if the |
| * user's quota will hold the payload |
| */ |
| int (*instantiate)(struct key *key, struct key_preparsed_payload *prep); |
| |
| /* update a key of this type (optional) |
| * - this method should call key_payload_reserve() to recalculate the |
| * quota consumption |
| * - the key must be locked against read when modifying |
| */ |
| int (*update)(struct key *key, struct key_preparsed_payload *prep); |
| |
| /* Preparse the data supplied to ->match() (optional). The |
| * data to be preparsed can be found in match_data->raw_data. |
| * The lookup type can also be set by this function. |
| */ |
| int (*match_preparse)(struct key_match_data *match_data); |
| |
| /* Free preparsed match data (optional). This should be supplied it |
| * ->match_preparse() is supplied. */ |
| void (*match_free)(struct key_match_data *match_data); |
| |
| /* clear some of the data from a key on revokation (optional) |
| * - the key's semaphore will be write-locked by the caller |
| */ |
| void (*revoke)(struct key *key); |
| |
| /* clear the data from a key (optional) */ |
| void (*destroy)(struct key *key); |
| |
| /* describe a key */ |
| void (*describe)(const struct key *key, struct seq_file *p); |
| |
| /* read a key's data (optional) |
| * - permission checks will be done by the caller |
| * - the key's semaphore will be readlocked by the caller |
| * - should return the amount of data that could be read, no matter how |
| * much is copied into the buffer |
| * - shouldn't do the copy if the buffer is NULL |
| */ |
| long (*read)(const struct key *key, char __user *buffer, size_t buflen); |
| |
| /* handle request_key() for this type instead of invoking |
| * /sbin/request-key (optional) |
| * - key is the key to instantiate |
| * - authkey is the authority to assume when instantiating this key |
| * - op is the operation to be done, usually "create" |
| * - the call must not return until the instantiation process has run |
| * its course |
| */ |
| request_key_actor_t request_key; |
| |
| /* Look up a keyring access restriction (optional) |
| * |
| * - NULL is a valid return value (meaning the requested restriction |
| * is known but will never block addition of a key) |
| * - should return -EINVAL if the restriction is unknown |
| */ |
| struct key_restriction *(*lookup_restriction)(const char *params); |
| |
| /* internal fields */ |
| struct list_head link; /* link in types list */ |
| struct lock_class_key lock_class; /* key->sem lock class */ |
| } __randomize_layout; |
| |
| extern struct key_type key_type_keyring; |
| |
| extern int register_key_type(struct key_type *ktype); |
| extern void unregister_key_type(struct key_type *ktype); |
| |
| extern int key_payload_reserve(struct key *key, size_t datalen); |
| extern int key_instantiate_and_link(struct key *key, |
| const void *data, |
| size_t datalen, |
| struct key *keyring, |
| struct key *instkey); |
| extern int key_reject_and_link(struct key *key, |
| unsigned timeout, |
| unsigned error, |
| struct key *keyring, |
| struct key *instkey); |
| extern void complete_request_key(struct key_construction *cons, int error); |
| |
| static inline int key_negate_and_link(struct key *key, |
| unsigned timeout, |
| struct key *keyring, |
| struct key *instkey) |
| { |
| return key_reject_and_link(key, timeout, ENOKEY, keyring, instkey); |
| } |
| |
| extern int generic_key_instantiate(struct key *key, struct key_preparsed_payload *prep); |
| |
| #endif /* CONFIG_KEYS */ |
| #endif /* _LINUX_KEY_TYPE_H */ |