1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* |
3 | * net/tipc/crypto.h: Include file for TIPC crypto |
4 | * |
5 | * Copyright (c) 2019, Ericsson AB |
6 | * All rights reserved. |
7 | * |
8 | * Redistribution and use in source and binary forms, with or without |
9 | * modification, are permitted provided that the following conditions are met: |
10 | * |
11 | * 1. Redistributions of source code must retain the above copyright |
12 | * notice, this list of conditions and the following disclaimer. |
13 | * 2. Redistributions in binary form must reproduce the above copyright |
14 | * notice, this list of conditions and the following disclaimer in the |
15 | * documentation and/or other materials provided with the distribution. |
16 | * 3. Neither the names of the copyright holders nor the names of its |
17 | * contributors may be used to endorse or promote products derived from |
18 | * this software without specific prior written permission. |
19 | * |
20 | * Alternatively, this software may be distributed under the terms of the |
21 | * GNU General Public License ("GPL") version 2 as published by the Free |
22 | * Software Foundation. |
23 | * |
24 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
25 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
28 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
29 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
30 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
31 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
32 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
33 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
34 | * POSSIBILITY OF SUCH DAMAGE. |
35 | */ |
36 | #ifdef CONFIG_TIPC_CRYPTO |
37 | #ifndef _TIPC_CRYPTO_H |
38 | #define _TIPC_CRYPTO_H |
39 | |
40 | #include "core.h" |
41 | #include "node.h" |
42 | #include "msg.h" |
43 | #include "bearer.h" |
44 | |
45 | #define TIPC_EVERSION 7 |
46 | |
47 | /* AEAD aes(gcm) */ |
48 | #define TIPC_AES_GCM_KEY_SIZE_128 16 |
49 | #define TIPC_AES_GCM_KEY_SIZE_192 24 |
50 | #define TIPC_AES_GCM_KEY_SIZE_256 32 |
51 | |
52 | #define TIPC_AES_GCM_SALT_SIZE 4 |
53 | #define TIPC_AES_GCM_IV_SIZE 12 |
54 | #define TIPC_AES_GCM_TAG_SIZE 16 |
55 | |
56 | /* |
57 | * TIPC crypto modes: |
58 | * - CLUSTER_KEY: |
59 | * One single key is used for both TX & RX in all nodes in the cluster. |
60 | * - PER_NODE_KEY: |
61 | * Each nodes in the cluster has one TX key, for RX a node needs to know |
62 | * its peers' TX key for the decryption of messages from those nodes. |
63 | */ |
64 | enum { |
65 | CLUSTER_KEY = 1, |
66 | PER_NODE_KEY = (1 << 1), |
67 | }; |
68 | |
69 | extern int sysctl_tipc_max_tfms __read_mostly; |
70 | extern int sysctl_tipc_key_exchange_enabled __read_mostly; |
71 | |
72 | /* |
73 | * TIPC encryption message format: |
74 | * |
75 | * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 |
76 | * 1 0 9 8 7 6 5 4|3 2 1 0 9 8 7 6|5 4 3 2 1 0 9 8|7 6 5 4 3 2 1 0 |
77 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
78 | * w0:|Ver=7| User |D|TX |RX |K|M|N| Rsvd | |
79 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
80 | * w1:| Seqno | |
81 | * w2:| (8 octets) | |
82 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
83 | * w3:\ Prevnode \ |
84 | * / (4 or 16 octets) / |
85 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
86 | * \ \ |
87 | * / Encrypted complete TIPC V2 header and user data / |
88 | * \ \ |
89 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
90 | * | | |
91 | * | AuthTag | |
92 | * | (16 octets) | |
93 | * | | |
94 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
95 | * |
96 | * Word0: |
97 | * Ver : = 7 i.e. TIPC encryption message version |
98 | * User : = 7 (for LINK_PROTOCOL); = 13 (for LINK_CONFIG) or = 0 |
99 | * D : The destined bit i.e. the message's destination node is |
100 | * "known" or not at the message encryption |
101 | * TX : TX key used for the message encryption |
102 | * RX : Currently RX active key corresponding to the destination |
103 | * node's TX key (when the "D" bit is set) |
104 | * K : Keep-alive bit (for RPS, LINK_PROTOCOL/STATE_MSG only) |
105 | * M : Bit indicates if sender has master key |
106 | * N : Bit indicates if sender has no RX keys corresponding to the |
107 | * receiver's TX (when the "D" bit is set) |
108 | * Rsvd : Reserved bit, field |
109 | * Word1-2: |
110 | * Seqno : The 64-bit sequence number of the encrypted message, also |
111 | * part of the nonce used for the message encryption/decryption |
112 | * Word3-: |
113 | * Prevnode: The source node address, or ID in case LINK_CONFIG only |
114 | * AuthTag : The authentication tag for the message integrity checking |
115 | * generated by the message encryption |
116 | */ |
117 | struct tipc_ehdr { |
118 | union { |
119 | struct { |
120 | #if defined(__LITTLE_ENDIAN_BITFIELD) |
121 | __u8 destined:1, |
122 | user:4, |
123 | version:3; |
124 | __u8 reserved_1:1, |
125 | rx_nokey:1, |
126 | master_key:1, |
127 | keepalive:1, |
128 | rx_key_active:2, |
129 | tx_key:2; |
130 | #elif defined(__BIG_ENDIAN_BITFIELD) |
131 | __u8 version:3, |
132 | user:4, |
133 | destined:1; |
134 | __u8 tx_key:2, |
135 | rx_key_active:2, |
136 | keepalive:1, |
137 | master_key:1, |
138 | rx_nokey:1, |
139 | reserved_1:1; |
140 | #else |
141 | #error "Please fix <asm/byteorder.h>" |
142 | #endif |
143 | __be16 reserved_2; |
144 | } __packed; |
145 | __be32 w0; |
146 | }; |
147 | __be64 seqno; |
148 | union { |
149 | __be32 addr; |
150 | __u8 id[NODE_ID_LEN]; /* For a LINK_CONFIG message only! */ |
151 | }; |
152 | #define EHDR_SIZE (offsetof(struct tipc_ehdr, addr) + sizeof(__be32)) |
153 | #define EHDR_CFG_SIZE (sizeof(struct tipc_ehdr)) |
154 | #define EHDR_MIN_SIZE (EHDR_SIZE) |
155 | #define EHDR_MAX_SIZE (EHDR_CFG_SIZE) |
156 | #define EMSG_OVERHEAD (EHDR_SIZE + TIPC_AES_GCM_TAG_SIZE) |
157 | } __packed; |
158 | |
159 | int tipc_crypto_start(struct tipc_crypto **crypto, struct net *net, |
160 | struct tipc_node *node); |
161 | void tipc_crypto_stop(struct tipc_crypto **crypto); |
162 | void tipc_crypto_timeout(struct tipc_crypto *rx); |
163 | int tipc_crypto_xmit(struct net *net, struct sk_buff **skb, |
164 | struct tipc_bearer *b, struct tipc_media_addr *dst, |
165 | struct tipc_node *__dnode); |
166 | int tipc_crypto_rcv(struct net *net, struct tipc_crypto *rx, |
167 | struct sk_buff **skb, struct tipc_bearer *b); |
168 | int tipc_crypto_key_init(struct tipc_crypto *c, struct tipc_aead_key *ukey, |
169 | u8 mode, bool master_key); |
170 | void tipc_crypto_key_flush(struct tipc_crypto *c); |
171 | int tipc_crypto_key_distr(struct tipc_crypto *tx, u8 key, |
172 | struct tipc_node *dest); |
173 | void tipc_crypto_msg_rcv(struct net *net, struct sk_buff *skb); |
174 | void tipc_crypto_rekeying_sched(struct tipc_crypto *tx, bool changed, |
175 | u32 new_intv); |
176 | int tipc_aead_key_validate(struct tipc_aead_key *ukey, struct genl_info *info); |
177 | bool tipc_ehdr_validate(struct sk_buff *skb); |
178 | |
179 | static inline u32 msg_key_gen(struct tipc_msg *m) |
180 | { |
181 | return msg_bits(m, w: 4, pos: 16, mask: 0xffff); |
182 | } |
183 | |
184 | static inline void msg_set_key_gen(struct tipc_msg *m, u32 gen) |
185 | { |
186 | msg_set_bits(m, w: 4, pos: 16, mask: 0xffff, val: gen); |
187 | } |
188 | |
189 | static inline u32 msg_key_mode(struct tipc_msg *m) |
190 | { |
191 | return msg_bits(m, w: 4, pos: 0, mask: 0xf); |
192 | } |
193 | |
194 | static inline void msg_set_key_mode(struct tipc_msg *m, u32 mode) |
195 | { |
196 | msg_set_bits(m, w: 4, pos: 0, mask: 0xf, val: mode); |
197 | } |
198 | |
199 | #endif /* _TIPC_CRYPTO_H */ |
200 | #endif |
201 | |