1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _FS_CEPH_AUTH_H
3 #define _FS_CEPH_AUTH_H
4 
5 #include <linux/ceph/types.h>
6 #include <linux/ceph/buffer.h>
7 
8 /*
9  * Abstract interface for communicating with the authenticate module.
10  * There is some handshake that takes place between us and the monitor
11  * to acquire the necessary keys.  These are used to generate an
12  * 'authorizer' that we use when connecting to a service (mds, osd).
13  */
14 
15 struct ceph_auth_client;
16 struct ceph_msg;
17 
18 struct ceph_authorizer {
19 	void (*destroy)(struct ceph_authorizer *);
20 };
21 
22 struct ceph_auth_handshake {
23 	struct ceph_authorizer *authorizer;
24 	void *authorizer_buf;
25 	size_t authorizer_buf_len;
26 	void *authorizer_reply_buf;
27 	size_t authorizer_reply_buf_len;
28 	int (*sign_message)(struct ceph_auth_handshake *auth,
29 			    struct ceph_msg *msg);
30 	int (*check_message_signature)(struct ceph_auth_handshake *auth,
31 				       struct ceph_msg *msg);
32 };
33 
34 struct ceph_auth_client_ops {
35 	const char *name;
36 
37 	/*
38 	 * true if we are authenticated and can connect to
39 	 * services.
40 	 */
41 	int (*is_authenticated)(struct ceph_auth_client *ac);
42 
43 	/*
44 	 * true if we should (re)authenticate, e.g., when our tickets
45 	 * are getting old and crusty.
46 	 */
47 	int (*should_authenticate)(struct ceph_auth_client *ac);
48 
49 	/*
50 	 * build requests and process replies during monitor
51 	 * handshake.  if handle_reply returns -EAGAIN, we build
52 	 * another request.
53 	 */
54 	int (*build_request)(struct ceph_auth_client *ac, void *buf, void *end);
55 	int (*handle_reply)(struct ceph_auth_client *ac, int result,
56 			    void *buf, void *end);
57 
58 	/*
59 	 * Create authorizer for connecting to a service, and verify
60 	 * the response to authenticate the service.
61 	 */
62 	int (*create_authorizer)(struct ceph_auth_client *ac, int peer_type,
63 				 struct ceph_auth_handshake *auth);
64 	/* ensure that an existing authorizer is up to date */
65 	int (*update_authorizer)(struct ceph_auth_client *ac, int peer_type,
66 				 struct ceph_auth_handshake *auth);
67 	int (*add_authorizer_challenge)(struct ceph_auth_client *ac,
68 					struct ceph_authorizer *a,
69 					void *challenge_buf,
70 					int challenge_buf_len);
71 	int (*verify_authorizer_reply)(struct ceph_auth_client *ac,
72 				       struct ceph_authorizer *a);
73 	void (*invalidate_authorizer)(struct ceph_auth_client *ac,
74 				      int peer_type);
75 
76 	/* reset when we (re)connect to a monitor */
77 	void (*reset)(struct ceph_auth_client *ac);
78 
79 	void (*destroy)(struct ceph_auth_client *ac);
80 
81 	int (*sign_message)(struct ceph_auth_handshake *auth,
82 			    struct ceph_msg *msg);
83 	int (*check_message_signature)(struct ceph_auth_handshake *auth,
84 				       struct ceph_msg *msg);
85 };
86 
87 struct ceph_auth_client {
88 	u32 protocol;           /* CEPH_AUTH_* */
89 	void *private;          /* for use by protocol implementation */
90 	const struct ceph_auth_client_ops *ops;  /* null iff protocol==0 */
91 
92 	bool negotiating;       /* true if negotiating protocol */
93 	const char *name;       /* entity name */
94 	u64 global_id;          /* our unique id in system */
95 	const struct ceph_crypto_key *key;     /* our secret key */
96 	unsigned want_keys;     /* which services we want */
97 
98 	struct mutex mutex;
99 };
100 
101 extern struct ceph_auth_client *ceph_auth_init(const char *name,
102 					       const struct ceph_crypto_key *key);
103 extern void ceph_auth_destroy(struct ceph_auth_client *ac);
104 
105 extern void ceph_auth_reset(struct ceph_auth_client *ac);
106 
107 extern int ceph_auth_build_hello(struct ceph_auth_client *ac,
108 				 void *buf, size_t len);
109 extern int ceph_handle_auth_reply(struct ceph_auth_client *ac,
110 				  void *buf, size_t len,
111 				  void *reply_buf, size_t reply_len);
112 int ceph_auth_entity_name_encode(const char *name, void **p, void *end);
113 
114 extern int ceph_build_auth(struct ceph_auth_client *ac,
115 		    void *msg_buf, size_t msg_len);
116 
117 extern int ceph_auth_is_authenticated(struct ceph_auth_client *ac);
118 extern int ceph_auth_create_authorizer(struct ceph_auth_client *ac,
119 				       int peer_type,
120 				       struct ceph_auth_handshake *auth);
121 void ceph_auth_destroy_authorizer(struct ceph_authorizer *a);
122 extern int ceph_auth_update_authorizer(struct ceph_auth_client *ac,
123 				       int peer_type,
124 				       struct ceph_auth_handshake *a);
125 int ceph_auth_add_authorizer_challenge(struct ceph_auth_client *ac,
126 				       struct ceph_authorizer *a,
127 				       void *challenge_buf,
128 				       int challenge_buf_len);
129 extern int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac,
130 					     struct ceph_authorizer *a);
131 extern void ceph_auth_invalidate_authorizer(struct ceph_auth_client *ac,
132 					    int peer_type);
133 
ceph_auth_sign_message(struct ceph_auth_handshake * auth,struct ceph_msg * msg)134 static inline int ceph_auth_sign_message(struct ceph_auth_handshake *auth,
135 					 struct ceph_msg *msg)
136 {
137 	if (auth->sign_message)
138 		return auth->sign_message(auth, msg);
139 	return 0;
140 }
141 
142 static inline
ceph_auth_check_message_signature(struct ceph_auth_handshake * auth,struct ceph_msg * msg)143 int ceph_auth_check_message_signature(struct ceph_auth_handshake *auth,
144 				      struct ceph_msg *msg)
145 {
146 	if (auth->check_message_signature)
147 		return auth->check_message_signature(auth, msg);
148 	return 0;
149 }
150 #endif
151