1 /* Definitions for key type implementations
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
12 #ifndef _LINUX_KEY_TYPE_H
13 #define _LINUX_KEY_TYPE_H
15 #include <linux/key.h>
16 #include <linux/errno.h>
20 struct kernel_pkey_query;
21 struct kernel_pkey_params;
24 * Pre-parsed payload, used by key add, update and instantiate.
26 * This struct will be cleared and data and datalen will be set with the data
27 * and length parameters from the caller and quotalen will be set from
28 * def_datalen from the key type. Then if the preparse() op is provided by the
29 * key type, that will be called. Then the struct will be passed to the
30 * instantiate() or the update() op.
32 * If the preparse() op is given, the free_preparse() op will be called to
35 struct key_preparsed_payload {
36 char *description; /* Proposed key description (or NULL) */
37 union key_payload payload; /* Proposed payload */
38 const void *data; /* Raw data */
39 size_t datalen; /* Raw datalen */
40 size_t quotalen; /* Quota length for proposed payload */
41 time64_t expiry; /* Expiry time of key */
44 typedef int (*request_key_actor_t)(struct key *auth_key, void *aux);
47 * Preparsed matching criterion.
49 struct key_match_data {
50 /* Comparison function, defaults to exact description match, but can be
51 * overridden by type->match_preparse(). Should return true if a match
52 * is found and false if not.
54 bool (*cmp)(const struct key *key,
55 const struct key_match_data *match_data);
57 const void *raw_data; /* Raw match data */
58 void *preparsed; /* For ->match_preparse() to stash stuff */
59 unsigned lookup_type; /* Type of lookup for this search. */
60 #define KEYRING_SEARCH_LOOKUP_DIRECT 0x0000 /* Direct lookup by description. */
61 #define KEYRING_SEARCH_LOOKUP_ITERATE 0x0001 /* Iterative search. */
65 * kernel managed key type definition
68 /* name of the type */
71 /* default payload length for quota precalculation (optional)
72 * - this can be used instead of calling key_payload_reserve(), that
73 * function only needs to be called if the real datalen is different
78 #define KEY_TYPE_NET_DOMAIN 0x00000001 /* Keys of this type have a net namespace domain */
80 /* vet a description */
81 int (*vet_description)(const char *description);
83 /* Preparse the data blob from userspace that is to be the payload,
84 * generating a proposed description and payload that will be handed to
85 * the instantiate() and update() ops.
87 int (*preparse)(struct key_preparsed_payload *prep);
89 /* Free a preparse data structure.
91 void (*free_preparse)(struct key_preparsed_payload *prep);
93 /* instantiate a key of this type
94 * - this method should call key_payload_reserve() to determine if the
95 * user's quota will hold the payload
97 int (*instantiate)(struct key *key, struct key_preparsed_payload *prep);
99 /* update a key of this type (optional)
100 * - this method should call key_payload_reserve() to recalculate the
102 * - the key must be locked against read when modifying
104 int (*update)(struct key *key, struct key_preparsed_payload *prep);
106 /* Preparse the data supplied to ->match() (optional). The
107 * data to be preparsed can be found in match_data->raw_data.
108 * The lookup type can also be set by this function.
110 int (*match_preparse)(struct key_match_data *match_data);
112 /* Free preparsed match data (optional). This should be supplied it
113 * ->match_preparse() is supplied. */
114 void (*match_free)(struct key_match_data *match_data);
116 /* clear some of the data from a key on revokation (optional)
117 * - the key's semaphore will be write-locked by the caller
119 void (*revoke)(struct key *key);
121 /* clear the data from a key (optional) */
122 void (*destroy)(struct key *key);
125 void (*describe)(const struct key *key, struct seq_file *p);
127 /* read a key's data (optional)
128 * - permission checks will be done by the caller
129 * - the key's semaphore will be readlocked by the caller
130 * - should return the amount of data that could be read, no matter how
131 * much is copied into the buffer
132 * - shouldn't do the copy if the buffer is NULL
134 long (*read)(const struct key *key, char __user *buffer, size_t buflen);
136 /* handle request_key() for this type instead of invoking
137 * /sbin/request-key (optional)
138 * - key is the key to instantiate
139 * - authkey is the authority to assume when instantiating this key
140 * - op is the operation to be done, usually "create"
141 * - the call must not return until the instantiation process has run
144 request_key_actor_t request_key;
146 /* Look up a keyring access restriction (optional)
148 * - NULL is a valid return value (meaning the requested restriction
149 * is known but will never block addition of a key)
150 * - should return -EINVAL if the restriction is unknown
152 struct key_restriction *(*lookup_restriction)(const char *params);
154 /* Asymmetric key accessor functions. */
155 int (*asym_query)(const struct kernel_pkey_params *params,
156 struct kernel_pkey_query *info);
157 int (*asym_eds_op)(struct kernel_pkey_params *params,
158 const void *in, void *out);
159 int (*asym_verify_signature)(struct kernel_pkey_params *params,
160 const void *in, const void *in2);
162 /* internal fields */
163 struct list_head link; /* link in types list */
164 struct lock_class_key lock_class; /* key->sem lock class */
165 } __randomize_layout;
167 extern struct key_type key_type_keyring;
169 extern int register_key_type(struct key_type *ktype);
170 extern void unregister_key_type(struct key_type *ktype);
172 extern int key_payload_reserve(struct key *key, size_t datalen);
173 extern int key_instantiate_and_link(struct key *key,
177 struct key *authkey);
178 extern int key_reject_and_link(struct key *key,
182 struct key *authkey);
183 extern void complete_request_key(struct key *authkey, int error);
185 static inline int key_negate_and_link(struct key *key,
190 return key_reject_and_link(key, timeout, ENOKEY, keyring, authkey);
193 extern int generic_key_instantiate(struct key *key, struct key_preparsed_payload *prep);
195 #endif /* CONFIG_KEYS */
196 #endif /* _LINUX_KEY_TYPE_H */