1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* Definitions for key type implementations
4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
8 #ifndef _LINUX_KEY_TYPE_H
9 #define _LINUX_KEY_TYPE_H
11 #include <linux/key.h>
12 #include <linux/errno.h>
16 struct kernel_pkey_query
;
17 struct kernel_pkey_params
;
20 * Pre-parsed payload, used by key add, update and instantiate.
22 * This struct will be cleared and data and datalen will be set with the data
23 * and length parameters from the caller and quotalen will be set from
24 * def_datalen from the key type. Then if the preparse() op is provided by the
25 * key type, that will be called. Then the struct will be passed to the
26 * instantiate() or the update() op.
28 * If the preparse() op is given, the free_preparse() op will be called to
31 struct key_preparsed_payload
{
32 char *description
; /* Proposed key description (or NULL) */
33 union key_payload payload
; /* Proposed payload */
34 const void *data
; /* Raw data */
35 size_t datalen
; /* Raw datalen */
36 size_t quotalen
; /* Quota length for proposed payload */
37 time64_t expiry
; /* Expiry time of key */
40 typedef int (*request_key_actor_t
)(struct key
*auth_key
, void *aux
);
43 * Preparsed matching criterion.
45 struct key_match_data
{
46 /* Comparison function, defaults to exact description match, but can be
47 * overridden by type->match_preparse(). Should return true if a match
48 * is found and false if not.
50 bool (*cmp
)(const struct key
*key
,
51 const struct key_match_data
*match_data
);
53 const void *raw_data
; /* Raw match data */
54 void *preparsed
; /* For ->match_preparse() to stash stuff */
55 unsigned lookup_type
; /* Type of lookup for this search. */
56 #define KEYRING_SEARCH_LOOKUP_DIRECT 0x0000 /* Direct lookup by description. */
57 #define KEYRING_SEARCH_LOOKUP_ITERATE 0x0001 /* Iterative search. */
61 * kernel managed key type definition
64 /* name of the type */
67 /* default payload length for quota precalculation (optional)
68 * - this can be used instead of calling key_payload_reserve(), that
69 * function only needs to be called if the real datalen is different
74 #define KEY_TYPE_NET_DOMAIN 0x00000001 /* Keys of this type have a net namespace domain */
76 /* vet a description */
77 int (*vet_description
)(const char *description
);
79 /* Preparse the data blob from userspace that is to be the payload,
80 * generating a proposed description and payload that will be handed to
81 * the instantiate() and update() ops.
83 int (*preparse
)(struct key_preparsed_payload
*prep
);
85 /* Free a preparse data structure.
87 void (*free_preparse
)(struct key_preparsed_payload
*prep
);
89 /* instantiate a key of this type
90 * - this method should call key_payload_reserve() to determine if the
91 * user's quota will hold the payload
93 int (*instantiate
)(struct key
*key
, struct key_preparsed_payload
*prep
);
95 /* update a key of this type (optional)
96 * - this method should call key_payload_reserve() to recalculate the
98 * - the key must be locked against read when modifying
100 int (*update
)(struct key
*key
, struct key_preparsed_payload
*prep
);
102 /* Preparse the data supplied to ->match() (optional). The
103 * data to be preparsed can be found in match_data->raw_data.
104 * The lookup type can also be set by this function.
106 int (*match_preparse
)(struct key_match_data
*match_data
);
108 /* Free preparsed match data (optional). This should be supplied it
109 * ->match_preparse() is supplied. */
110 void (*match_free
)(struct key_match_data
*match_data
);
112 /* clear some of the data from a key on revokation (optional)
113 * - the key's semaphore will be write-locked by the caller
115 void (*revoke
)(struct key
*key
);
117 /* clear the data from a key (optional) */
118 void (*destroy
)(struct key
*key
);
121 void (*describe
)(const struct key
*key
, struct seq_file
*p
);
123 /* read a key's data (optional)
124 * - permission checks will be done by the caller
125 * - the key's semaphore will be readlocked by the caller
126 * - should return the amount of data that could be read, no matter how
127 * much is copied into the buffer
128 * - shouldn't do the copy if the buffer is NULL
130 long (*read
)(const struct key
*key
, char *buffer
, size_t buflen
);
132 /* handle request_key() for this type instead of invoking
133 * /sbin/request-key (optional)
134 * - key is the key to instantiate
135 * - authkey is the authority to assume when instantiating this key
136 * - op is the operation to be done, usually "create"
137 * - the call must not return until the instantiation process has run
140 request_key_actor_t request_key
;
142 /* Look up a keyring access restriction (optional)
144 * - NULL is a valid return value (meaning the requested restriction
145 * is known but will never block addition of a key)
146 * - should return -EINVAL if the restriction is unknown
148 struct key_restriction
*(*lookup_restriction
)(const char *params
);
150 /* Asymmetric key accessor functions. */
151 int (*asym_query
)(const struct kernel_pkey_params
*params
,
152 struct kernel_pkey_query
*info
);
153 int (*asym_eds_op
)(struct kernel_pkey_params
*params
,
154 const void *in
, void *out
);
155 int (*asym_verify_signature
)(struct kernel_pkey_params
*params
,
156 const void *in
, const void *in2
);
158 /* internal fields */
159 struct list_head link
; /* link in types list */
160 struct lock_class_key lock_class
; /* key->sem lock class */
161 } __randomize_layout
;
163 extern struct key_type key_type_keyring
;
165 extern int register_key_type(struct key_type
*ktype
);
166 extern void unregister_key_type(struct key_type
*ktype
);
168 extern int key_payload_reserve(struct key
*key
, size_t datalen
);
169 extern int key_instantiate_and_link(struct key
*key
,
173 struct key
*authkey
);
174 extern int key_reject_and_link(struct key
*key
,
178 struct key
*authkey
);
179 extern void complete_request_key(struct key
*authkey
, int error
);
181 static inline int key_negate_and_link(struct key
*key
,
186 return key_reject_and_link(key
, timeout
, ENOKEY
, keyring
, authkey
);
189 extern int generic_key_instantiate(struct key
*key
, struct key_preparsed_payload
*prep
);
191 #endif /* CONFIG_KEYS */
192 #endif /* _LINUX_KEY_TYPE_H */