2 * Copyright (c) 2020 Doc.ai and/or its affiliates.
3 * Copyright (c) 2015-2020 Jason A. Donenfeld <Jason@zx2c4.com>.
4 * Copyright (c) 2019-2020 Matt Dunwoodie <ncon@noconroy.net>.
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
9 * http://www.apache.org/licenses/LICENSE-2.0
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
19 #include <openssl/rand.h>
20 #include <vlib/vlib.h>
22 #include <wireguard/wireguard_cookie.h>
23 #include <wireguard/wireguard_chachapoly.h>
24 #include <wireguard/wireguard.h>
26 static void cookie_precompute_key (uint8_t *,
27 const uint8_t[COOKIE_INPUT_SIZE],
29 static void cookie_macs_mac1 (message_macs_t *, const void *, size_t,
30 const uint8_t[COOKIE_KEY_SIZE]);
31 static void cookie_macs_mac2 (message_macs_t *, const void *, size_t,
32 const uint8_t[COOKIE_COOKIE_SIZE]);
33 static void cookie_checker_make_cookie (vlib_main_t *vm, cookie_checker_t *,
34 uint8_t[COOKIE_COOKIE_SIZE],
35 ip46_address_t *ip, u16 udp_port);
37 /* Public Functions */
39 cookie_maker_init (cookie_maker_t * cp, const uint8_t key[COOKIE_INPUT_SIZE])
41 clib_memset (cp, 0, sizeof (*cp));
42 cookie_precompute_key (cp->cp_mac1_key, key, COOKIE_MAC1_KEY_LABEL);
43 cookie_precompute_key (cp->cp_cookie_key, key, COOKIE_COOKIE_KEY_LABEL);
47 cookie_checker_update (cookie_checker_t * cc, uint8_t key[COOKIE_INPUT_SIZE])
51 cookie_precompute_key (cc->cc_mac1_key, key, COOKIE_MAC1_KEY_LABEL);
52 cookie_precompute_key (cc->cc_cookie_key, key, COOKIE_COOKIE_KEY_LABEL);
56 clib_memset (cc->cc_mac1_key, 0, sizeof (cc->cc_mac1_key));
57 clib_memset (cc->cc_cookie_key, 0, sizeof (cc->cc_cookie_key));
62 cookie_checker_create_payload (vlib_main_t *vm, cookie_checker_t *cc,
64 uint8_t nonce[COOKIE_NONCE_SIZE],
65 uint8_t ecookie[COOKIE_ENCRYPTED_SIZE],
66 ip46_address_t *ip, u16 udp_port)
68 uint8_t cookie[COOKIE_COOKIE_SIZE];
70 cookie_checker_make_cookie (vm, cc, cookie, ip, udp_port);
71 RAND_bytes (nonce, COOKIE_NONCE_SIZE);
73 wg_xchacha20poly1305_encrypt (vm, cookie, COOKIE_COOKIE_SIZE, ecookie,
74 cm->mac1, COOKIE_MAC_SIZE, nonce,
77 wg_secure_zero_memory (cookie, sizeof (cookie));
81 cookie_maker_consume_payload (vlib_main_t *vm, cookie_maker_t *cp,
82 uint8_t nonce[COOKIE_NONCE_SIZE],
83 uint8_t ecookie[COOKIE_ENCRYPTED_SIZE])
85 uint8_t cookie[COOKIE_COOKIE_SIZE];
87 if (cp->cp_mac1_valid == 0)
92 if (!wg_xchacha20poly1305_decrypt (vm, ecookie, COOKIE_ENCRYPTED_SIZE,
93 cookie, cp->cp_mac1_last, COOKIE_MAC_SIZE,
94 nonce, cp->cp_cookie_key))
99 clib_memcpy (cp->cp_cookie, cookie, COOKIE_COOKIE_SIZE);
100 cp->cp_birthdate = vlib_time_now (vm);
101 cp->cp_mac1_valid = 0;
107 cookie_maker_mac (cookie_maker_t * cp, message_macs_t * cm, void *buf,
110 len = len - sizeof (message_macs_t);
111 cookie_macs_mac1 (cm, buf, len, cp->cp_mac1_key);
113 clib_memcpy (cp->cp_mac1_last, cm->mac1, COOKIE_MAC_SIZE);
114 cp->cp_mac1_valid = 1;
116 if (!wg_birthdate_has_expired (cp->cp_birthdate,
117 COOKIE_SECRET_MAX_AGE -
118 COOKIE_SECRET_LATENCY))
119 cookie_macs_mac2 (cm, buf, len, cp->cp_cookie);
121 clib_memset (cm->mac2, 0, COOKIE_MAC_SIZE);
124 enum cookie_mac_state
125 cookie_checker_validate_macs (vlib_main_t *vm, cookie_checker_t *cc,
126 message_macs_t *cm, void *buf, size_t len,
127 bool busy, ip46_address_t *ip, u16 udp_port)
129 message_macs_t our_cm;
130 uint8_t cookie[COOKIE_COOKIE_SIZE];
132 len = len - sizeof (message_macs_t);
133 cookie_macs_mac1 (&our_cm, buf, len, cc->cc_mac1_key);
135 /* If mac1 is invalid, we want to drop the packet */
136 if (clib_memcmp (our_cm.mac1, cm->mac1, COOKIE_MAC_SIZE) != 0)
140 return VALID_MAC_BUT_NO_COOKIE;
142 cookie_checker_make_cookie (vm, cc, cookie, ip, udp_port);
143 cookie_macs_mac2 (&our_cm, buf, len, cookie);
145 /* If the mac2 is invalid, we want to send a cookie response */
146 if (clib_memcmp (our_cm.mac2, cm->mac2, COOKIE_MAC_SIZE) != 0)
147 return VALID_MAC_BUT_NO_COOKIE;
149 return VALID_MAC_WITH_COOKIE;
152 /* Private functions */
154 cookie_precompute_key (uint8_t * key, const uint8_t input[COOKIE_INPUT_SIZE],
157 blake2s_state_t blake;
159 blake2s_init (&blake, COOKIE_KEY_SIZE);
160 blake2s_update (&blake, (const uint8_t *) label, strlen (label));
161 blake2s_update (&blake, input, COOKIE_INPUT_SIZE);
162 blake2s_final (&blake, key, COOKIE_KEY_SIZE);
166 cookie_macs_mac1 (message_macs_t * cm, const void *buf, size_t len,
167 const uint8_t key[COOKIE_KEY_SIZE])
169 blake2s_state_t state;
170 blake2s_init_key (&state, COOKIE_MAC_SIZE, key, COOKIE_KEY_SIZE);
171 blake2s_update (&state, buf, len);
172 blake2s_final (&state, cm->mac1, COOKIE_MAC_SIZE);
177 cookie_macs_mac2 (message_macs_t * cm, const void *buf, size_t len,
178 const uint8_t key[COOKIE_COOKIE_SIZE])
180 blake2s_state_t state;
181 blake2s_init_key (&state, COOKIE_MAC_SIZE, key, COOKIE_COOKIE_SIZE);
182 blake2s_update (&state, buf, len);
183 blake2s_update (&state, cm->mac1, COOKIE_MAC_SIZE);
184 blake2s_final (&state, cm->mac2, COOKIE_MAC_SIZE);
188 cookie_checker_make_cookie (vlib_main_t *vm, cookie_checker_t *cc,
189 uint8_t cookie[COOKIE_COOKIE_SIZE],
190 ip46_address_t *ip, u16 udp_port)
192 blake2s_state_t state;
194 if (wg_birthdate_has_expired (cc->cc_secret_birthdate,
195 COOKIE_SECRET_MAX_AGE))
197 cc->cc_secret_birthdate = vlib_time_now (vm);
198 RAND_bytes (cc->cc_secret, COOKIE_SECRET_SIZE);
201 blake2s_init_key (&state, COOKIE_COOKIE_SIZE, cc->cc_secret,
204 if (ip46_address_is_ip4 (ip))
206 blake2s_update (&state, ip->ip4.as_u8, sizeof (ip4_address_t));
210 blake2s_update (&state, ip->ip6.as_u8, sizeof (ip6_address_t));
212 blake2s_update (&state, (u8 *) & udp_port, sizeof (u16));
213 blake2s_final (&state, cookie, COOKIE_COOKIE_SIZE);
217 * fd.io coding-style-patch-verification: ON
220 * eval: (c-set-style "gnu")