David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 1 | /* Definitions for key type implementations |
| 2 | * |
| 3 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. |
| 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 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. |
| 10 | */ |
| 11 | |
| 12 | #ifndef _LINUX_KEY_TYPE_H |
| 13 | #define _LINUX_KEY_TYPE_H |
| 14 | |
| 15 | #include <linux/key.h> |
David Howells | 5935e6d | 2012-07-23 15:37:31 +0100 | [diff] [blame] | 16 | #include <linux/errno.h> |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 17 | |
| 18 | #ifdef CONFIG_KEYS |
| 19 | |
| 20 | /* |
| 21 | * key under-construction record |
| 22 | * - passed to the request_key actor if supplied |
| 23 | */ |
| 24 | struct key_construction { |
| 25 | struct key *key; /* key being constructed */ |
| 26 | struct key *authkey;/* authorisation for key being constructed */ |
| 27 | }; |
| 28 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 29 | /* |
| 30 | * Pre-parsed payload, used by key add, update and instantiate. |
| 31 | * |
| 32 | * This struct will be cleared and data and datalen will be set with the data |
| 33 | * and length parameters from the caller and quotalen will be set from |
| 34 | * def_datalen from the key type. Then if the preparse() op is provided by the |
| 35 | * key type, that will be called. Then the struct will be passed to the |
| 36 | * instantiate() or the update() op. |
| 37 | * |
| 38 | * If the preparse() op is given, the free_preparse() op will be called to |
| 39 | * clear the contents. |
| 40 | */ |
| 41 | struct key_preparsed_payload { |
| 42 | char *description; /* Proposed key description (or NULL) */ |
| 43 | void *type_data[2]; /* Private key-type data */ |
| 44 | void *payload; /* Proposed payload */ |
| 45 | const void *data; /* Raw data */ |
| 46 | size_t datalen; /* Raw datalen */ |
| 47 | size_t quotalen; /* Quota length for proposed payload */ |
David Howells | 008643b | 2013-08-30 16:07:37 +0100 | [diff] [blame] | 48 | bool trusted; /* True if key is trusted */ |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 49 | }; |
| 50 | |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 51 | typedef int (*request_key_actor_t)(struct key_construction *key, |
| 52 | const char *op, void *aux); |
| 53 | |
| 54 | /* |
| 55 | * kernel managed key type definition |
| 56 | */ |
| 57 | struct key_type { |
| 58 | /* name of the type */ |
| 59 | const char *name; |
| 60 | |
| 61 | /* default payload length for quota precalculation (optional) |
| 62 | * - this can be used instead of calling key_payload_reserve(), that |
| 63 | * function only needs to be called if the real datalen is different |
| 64 | */ |
| 65 | size_t def_datalen; |
| 66 | |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 67 | /* Default key search algorithm. */ |
| 68 | unsigned def_lookup_type; |
| 69 | #define KEYRING_SEARCH_LOOKUP_DIRECT 0x0000 /* Direct lookup by description. */ |
| 70 | #define KEYRING_SEARCH_LOOKUP_ITERATE 0x0001 /* Iterative search. */ |
| 71 | |
David Howells | b9fffa3 | 2011-03-07 15:05:59 +0000 | [diff] [blame] | 72 | /* vet a description */ |
| 73 | int (*vet_description)(const char *description); |
| 74 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 75 | /* Preparse the data blob from userspace that is to be the payload, |
| 76 | * generating a proposed description and payload that will be handed to |
| 77 | * the instantiate() and update() ops. |
| 78 | */ |
| 79 | int (*preparse)(struct key_preparsed_payload *prep); |
| 80 | |
| 81 | /* Free a preparse data structure. |
| 82 | */ |
| 83 | void (*free_preparse)(struct key_preparsed_payload *prep); |
| 84 | |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 85 | /* instantiate a key of this type |
| 86 | * - this method should call key_payload_reserve() to determine if the |
| 87 | * user's quota will hold the payload |
| 88 | */ |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 89 | int (*instantiate)(struct key *key, struct key_preparsed_payload *prep); |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 90 | |
| 91 | /* update a key of this type (optional) |
| 92 | * - this method should call key_payload_reserve() to recalculate the |
| 93 | * quota consumption |
| 94 | * - the key must be locked against read when modifying |
| 95 | */ |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 96 | int (*update)(struct key *key, struct key_preparsed_payload *prep); |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 97 | |
| 98 | /* match a key against a description */ |
| 99 | int (*match)(const struct key *key, const void *desc); |
| 100 | |
| 101 | /* clear some of the data from a key on revokation (optional) |
| 102 | * - the key's semaphore will be write-locked by the caller |
| 103 | */ |
| 104 | void (*revoke)(struct key *key); |
| 105 | |
| 106 | /* clear the data from a key (optional) */ |
| 107 | void (*destroy)(struct key *key); |
| 108 | |
| 109 | /* describe a key */ |
| 110 | void (*describe)(const struct key *key, struct seq_file *p); |
| 111 | |
| 112 | /* read a key's data (optional) |
| 113 | * - permission checks will be done by the caller |
| 114 | * - the key's semaphore will be readlocked by the caller |
| 115 | * - should return the amount of data that could be read, no matter how |
| 116 | * much is copied into the buffer |
| 117 | * - shouldn't do the copy if the buffer is NULL |
| 118 | */ |
| 119 | long (*read)(const struct key *key, char __user *buffer, size_t buflen); |
| 120 | |
| 121 | /* handle request_key() for this type instead of invoking |
| 122 | * /sbin/request-key (optional) |
| 123 | * - key is the key to instantiate |
| 124 | * - authkey is the authority to assume when instantiating this key |
| 125 | * - op is the operation to be done, usually "create" |
| 126 | * - the call must not return until the instantiation process has run |
| 127 | * its course |
| 128 | */ |
| 129 | request_key_actor_t request_key; |
| 130 | |
| 131 | /* internal fields */ |
| 132 | struct list_head link; /* link in types list */ |
David Howells | 7845bc39 | 2011-11-16 11:15:54 +0000 | [diff] [blame] | 133 | struct lock_class_key lock_class; /* key->sem lock class */ |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 134 | }; |
| 135 | |
| 136 | extern struct key_type key_type_keyring; |
| 137 | |
| 138 | extern int register_key_type(struct key_type *ktype); |
| 139 | extern void unregister_key_type(struct key_type *ktype); |
| 140 | |
| 141 | extern int key_payload_reserve(struct key *key, size_t datalen); |
| 142 | extern int key_instantiate_and_link(struct key *key, |
| 143 | const void *data, |
| 144 | size_t datalen, |
| 145 | struct key *keyring, |
| 146 | struct key *instkey); |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 147 | extern int key_reject_and_link(struct key *key, |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 148 | unsigned timeout, |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 149 | unsigned error, |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 150 | struct key *keyring, |
| 151 | struct key *instkey); |
| 152 | extern void complete_request_key(struct key_construction *cons, int error); |
| 153 | |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 154 | static inline int key_negate_and_link(struct key *key, |
| 155 | unsigned timeout, |
| 156 | struct key *keyring, |
| 157 | struct key *instkey) |
| 158 | { |
| 159 | return key_reject_and_link(key, timeout, ENOKEY, keyring, instkey); |
| 160 | } |
| 161 | |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 162 | #endif /* CONFIG_KEYS */ |
| 163 | #endif /* _LINUX_KEY_TYPE_H */ |