1 /* SCTP kernel implementation
2  * (C) Copyright 2007 Hewlett-Packard Development Company, L.P.
3  *
4  * This file is part of the SCTP kernel implementation
5  *
6  * This SCTP implementation is free software;
7  * you can redistribute it and/or modify it under the terms of
8  * the GNU General Public License as published by
9  * the Free Software Foundation; either version 2, or (at your option)
10  * any later version.
11  *
12  * This SCTP implementation is distributed in the hope that it
13  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
14  *                 ************************
15  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
16  * See the GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with GNU CC; see the file COPYING.  If not, write to
20  * the Free Software Foundation, 59 Temple Place - Suite 330,
21  * Boston, MA 02111-1307, USA.
22  *
23  * Please send any bug reports or fixes you make to the
24  * email address(es):
25  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
26  *
27  * Or submit a bug report through the following website:
28  *    http://www.sf.net/projects/lksctp
29  *
30  * Written or modified by:
31  *   Vlad Yasevich     <vladislav.yasevich@hp.com>
32  *
33  * Any bugs reported given to us we will try to fix... any fixes shared will
34  * be incorporated into the next SCTP release.
35  */
36 
37 #ifndef __sctp_auth_h__
38 #define __sctp_auth_h__
39 
40 #include <linux/list.h>
41 #include <linux/crypto.h>
42 
43 struct sctp_endpoint;
44 struct sctp_association;
45 struct sctp_authkey;
46 struct sctp_hmacalgo;
47 
48 /*
49  * Define a generic struct that will hold all the info
50  * necessary for an HMAC transform
51  */
52 struct sctp_hmac {
53 	__u16 hmac_id;		/* one of the above ids */
54 	char *hmac_name;	/* name for loading */
55 	__u16 hmac_len;		/* length of the signature */
56 };
57 
58 /* This is generic structure that containst authentication bytes used
59  * as keying material.  It's a what is referred to as byte-vector all
60  * over SCTP-AUTH
61  */
62 struct sctp_auth_bytes {
63 	atomic_t refcnt;
64 	__u32 len;
65 	__u8  data[];
66 };
67 
68 /* Definition for a shared key, weather endpoint or association */
69 struct sctp_shared_key {
70 	struct list_head key_list;
71 	__u16 key_id;
72 	struct sctp_auth_bytes *key;
73 };
74 
75 #define key_for_each(__key, __list_head) \
76 	list_for_each_entry(__key, __list_head, key_list)
77 
78 #define key_for_each_safe(__key, __tmp, __list_head) \
79 	list_for_each_entry_safe(__key, __tmp, __list_head, key_list)
80 
sctp_auth_key_hold(struct sctp_auth_bytes * key)81 static inline void sctp_auth_key_hold(struct sctp_auth_bytes *key)
82 {
83 	if (!key)
84 		return;
85 
86 	atomic_inc(&key->refcnt);
87 }
88 
89 void sctp_auth_key_put(struct sctp_auth_bytes *key);
90 struct sctp_shared_key *sctp_auth_shkey_create(__u16 key_id, gfp_t gfp);
91 void sctp_auth_destroy_keys(struct list_head *keys);
92 int sctp_auth_asoc_init_active_key(struct sctp_association *asoc, gfp_t gfp);
93 struct sctp_shared_key *sctp_auth_get_shkey(
94 				const struct sctp_association *asoc,
95 				__u16 key_id);
96 int sctp_auth_asoc_copy_shkeys(const struct sctp_endpoint *ep,
97 				struct sctp_association *asoc,
98 				gfp_t gfp);
99 int sctp_auth_init_hmacs(struct sctp_endpoint *ep, gfp_t gfp);
100 void sctp_auth_destroy_hmacs(struct crypto_hash *auth_hmacs[]);
101 struct sctp_hmac *sctp_auth_get_hmac(__u16 hmac_id);
102 struct sctp_hmac *sctp_auth_asoc_get_hmac(const struct sctp_association *asoc);
103 void sctp_auth_asoc_set_default_hmac(struct sctp_association *asoc,
104 				     struct sctp_hmac_algo_param *hmacs);
105 int sctp_auth_asoc_verify_hmac_id(const struct sctp_association *asoc,
106 				    __be16 hmac_id);
107 int sctp_auth_send_cid(sctp_cid_t chunk, const struct sctp_association *asoc);
108 int sctp_auth_recv_cid(sctp_cid_t chunk, const struct sctp_association *asoc);
109 void sctp_auth_calculate_hmac(const struct sctp_association *asoc,
110 			    struct sk_buff *skb,
111 			    struct sctp_auth_chunk *auth, gfp_t gfp);
112 
113 /* API Helpers */
114 int sctp_auth_ep_add_chunkid(struct sctp_endpoint *ep, __u8 chunk_id);
115 int sctp_auth_ep_set_hmacs(struct sctp_endpoint *ep,
116 			    struct sctp_hmacalgo *hmacs);
117 int sctp_auth_set_key(struct sctp_endpoint *ep,
118 		      struct sctp_association *asoc,
119 		      struct sctp_authkey *auth_key);
120 int sctp_auth_set_active_key(struct sctp_endpoint *ep,
121 		      struct sctp_association *asoc,
122 		      __u16 key_id);
123 int sctp_auth_del_key_id(struct sctp_endpoint *ep,
124 		      struct sctp_association *asoc,
125 		      __u16 key_id);
126 
127 #endif
128