include/crypto/public_key.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /* Asymmetric public-key algorithm definitions
   3  *
   4  * See Documentation/crypto/asymmetric-keys.rst
   5  *
   6  * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
   7  * Written by David Howells (dhowells@redhat.com)
   8  */
   9
  10 #ifndef _LINUX_PUBLIC_KEY_H
  11 #define _LINUX_PUBLIC_KEY_H
  12
  13 #include <linux/errno.h>
  14 #include <linux/keyctl.h>
  15 #include <linux/oid_registry.h>
  16
  17 /*
  18  * Cryptographic data for the public-key subtype of the asymmetric key type.
  19  *
  20  * Note that this may include private part of the key as well as the public
  21  * part.
  22  */
  23 struct public_key {
  24         void *key;
  25         u32 keylen;
  26         enum OID algo;
  27         void *params;
  28         u32 paramlen;
  29         bool key_is_private;
  30         const char *id_type;
  31         const char *pkey_algo;
  32         unsigned long key_eflags;       /* key extension flags */
  33 #define KEY_EFLAG_CA            0       /* set if the CA basic constraints is set */
  34 #define KEY_EFLAG_DIGITALSIG    1       /* set if the digitalSignature usage is set */
  35 #define KEY_EFLAG_KEYCERTSIGN   2       /* set if the keyCertSign usage is set */
  36 };
  37
  38 extern void public_key_free(struct public_key *key);
  39
  40 /*
  41  * Public key cryptography signature data
  42  */
  43 struct public_key_signature {
  44         struct asymmetric_key_id *auth_ids[3];
  45         u8 *s;                  /* Signature */
  46         u8 *digest;
  47         u32 s_size;             /* Number of bytes in signature */
  48         u32 digest_size;        /* Number of bytes in digest */
  49         const char *pkey_algo;
  50         const char *hash_algo;
  51         const char *encoding;
  52 };
  53
  54 extern void public_key_signature_free(struct public_key_signature *sig);
  55
  56 extern struct asymmetric_key_subtype public_key_subtype;
  57
  58 struct key;
  59 struct key_type;
  60 union key_payload;
  61
  62 extern int restrict_link_by_signature(struct key *dest_keyring,
  63                                       const struct key_type *type,
  64                                       const union key_payload *payload,
  65                                       struct key *trust_keyring);
  66
  67 extern int restrict_link_by_key_or_keyring(struct key *dest_keyring,
  68                                            const struct key_type *type,
  69                                            const union key_payload *payload,
  70                                            struct key *trusted);
  71
  72 extern int restrict_link_by_key_or_keyring_chain(struct key *trust_keyring,
  73                                                  const struct key_type *type,
  74                                                  const union key_payload *payload,
  75                                                  struct key *trusted);
  76
  77 #if IS_REACHABLE(CONFIG_ASYMMETRIC_KEY_TYPE)
  78 extern int restrict_link_by_ca(struct key *dest_keyring,
  79                                const struct key_type *type,
  80                                const union key_payload *payload,
  81                                struct key *trust_keyring);
  82 int restrict_link_by_digsig(struct key *dest_keyring,
  83                             const struct key_type *type,
  84                             const union key_payload *payload,
  85                             struct key *trust_keyring);
  86 #else
  87 static inline int restrict_link_by_ca(struct key *dest_keyring,
  88                                       const struct key_type *type,
  89                                       const union key_payload *payload,
  90                                       struct key *trust_keyring)
  91 {
  92         return 0;
  93 }
  94
  95 static inline int restrict_link_by_digsig(struct key *dest_keyring,
  96                                           const struct key_type *type,
  97                                           const union key_payload *payload,
  98                                           struct key *trust_keyring)
  99 {
 100         return 0;
 101 }
 102 #endif
 103
 104 extern int query_asymmetric_key(const struct kernel_pkey_params *,
 105                                 struct kernel_pkey_query *);
 106
 107 extern int verify_signature(const struct key *,
 108                             const struct public_key_signature *);
 109
 110 #if IS_REACHABLE(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE)
 111 int public_key_verify_signature(const struct public_key *pkey,
 112                                 const struct public_key_signature *sig);
 113 #else
 114 static inline
 115 int public_key_verify_signature(const struct public_key *pkey,
 116                                 const struct public_key_signature *sig)
 117 {
 118         return -EINVAL;
 119 }
 120 #endif
 121
 122 #endif /* _LINUX_PUBLIC_KEY_H */