/* $OpenBSD: wg_noise.h,v 1.2 2020/12/09 05:53:33 tb Exp $ */ /* * Copyright (C) 2015-2020 Jason A. Donenfeld . All Rights Reserved. * Copyright (C) 2019-2020 Matt Dunwoodie * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #ifndef __NOISE_H__ #define __NOISE_H__ #include #include #include #include #include #include #define NOISE_PUBLIC_KEY_LEN CURVE25519_KEY_SIZE #define NOISE_SYMMETRIC_KEY_LEN CHACHA20POLY1305_KEY_SIZE #define NOISE_TIMESTAMP_LEN (sizeof(uint64_t) + sizeof(uint32_t)) #define NOISE_AUTHTAG_LEN CHACHA20POLY1305_AUTHTAG_SIZE #define NOISE_HASH_LEN BLAKE2S_HASH_SIZE /* Protocol string constants */ #define NOISE_HANDSHAKE_NAME "Noise_IKpsk2_25519_ChaChaPoly_BLAKE2s" #define NOISE_IDENTIFIER_NAME "WireGuard v1 zx2c4 Jason@zx2c4.com" /* Constants for the counter */ #define COUNTER_BITS_TOTAL 8192 #define COUNTER_BITS (sizeof(unsigned long) * 8) #define COUNTER_NUM (COUNTER_BITS_TOTAL / COUNTER_BITS) #define COUNTER_WINDOW_SIZE (COUNTER_BITS_TOTAL - COUNTER_BITS) /* Constants for the keypair */ #define REKEY_AFTER_MESSAGES (1ull << 60) #define REJECT_AFTER_MESSAGES (UINT64_MAX - COUNTER_WINDOW_SIZE - 1) #define REKEY_AFTER_TIME 120 #define REKEY_AFTER_TIME_RECV 165 #define REJECT_AFTER_TIME 180 #define REJECT_INTERVAL (1000000000 / 50) /* fifty times per sec */ /* 24 = floor(log2(REJECT_INTERVAL)) */ #define REJECT_INTERVAL_MASK (~((1ull<<24)-1)) enum noise_state_hs { HS_ZEROED = 0, CREATED_INITIATION, CONSUMED_INITIATION, CREATED_RESPONSE, CONSUMED_RESPONSE, }; struct noise_handshake { enum noise_state_hs hs_state; uint32_t hs_local_index; uint32_t hs_remote_index; uint8_t hs_e[NOISE_PUBLIC_KEY_LEN]; uint8_t hs_hash[NOISE_HASH_LEN]; uint8_t hs_ck[NOISE_HASH_LEN]; }; struct noise_counter { struct rwlock c_lock; uint64_t c_send; uint64_t c_recv; unsigned long c_backtrack[COUNTER_NUM]; }; struct noise_keypair { SLIST_ENTRY(noise_keypair) kp_entry; int kp_valid; int kp_is_initiator; uint32_t kp_local_index; uint32_t kp_remote_index; uint8_t kp_send[NOISE_SYMMETRIC_KEY_LEN]; uint8_t kp_recv[NOISE_SYMMETRIC_KEY_LEN]; struct timespec kp_birthdate; /* nanouptime */ struct noise_counter kp_ctr; }; struct noise_remote { uint8_t r_public[NOISE_PUBLIC_KEY_LEN]; struct noise_local *r_local; uint8_t r_ss[NOISE_PUBLIC_KEY_LEN]; struct rwlock r_handshake_lock; struct noise_handshake r_handshake; uint8_t r_psk[NOISE_SYMMETRIC_KEY_LEN]; uint8_t r_timestamp[NOISE_TIMESTAMP_LEN]; struct timespec r_last_init; /* nanouptime */ struct rwlock r_keypair_lock; SLIST_HEAD(,noise_keypair) r_unused_keypairs; struct noise_keypair *r_next, *r_current, *r_previous; struct noise_keypair r_keypair[3]; /* 3: next, current, previous. */ }; struct noise_local { struct rwlock l_identity_lock; int l_has_identity; uint8_t l_public[NOISE_PUBLIC_KEY_LEN]; uint8_t l_private[NOISE_PUBLIC_KEY_LEN]; struct noise_upcall { void *u_arg; struct noise_remote * (*u_remote_get)(void *, uint8_t[NOISE_PUBLIC_KEY_LEN]); uint32_t (*u_index_set)(void *, struct noise_remote *); void (*u_index_drop)(void *, uint32_t); } l_upcall; }; /* Set/Get noise parameters */ void noise_local_init(struct noise_local *, struct noise_upcall *); void noise_local_lock_identity(struct noise_local *); void noise_local_unlock_identity(struct noise_local *); int noise_local_set_private(struct noise_local *, uint8_t[NOISE_PUBLIC_KEY_LEN]); int noise_local_keys(struct noise_local *, uint8_t[NOISE_PUBLIC_KEY_LEN], uint8_t[NOISE_PUBLIC_KEY_LEN]); void noise_remote_init(struct noise_remote *, uint8_t[NOISE_PUBLIC_KEY_LEN], struct noise_local *); int noise_remote_set_psk(struct noise_remote *, uint8_t[NOISE_SYMMETRIC_KEY_LEN]); int noise_remote_keys(struct noise_remote *, uint8_t[NOISE_PUBLIC_KEY_LEN], uint8_t[NOISE_SYMMETRIC_KEY_LEN]); /* Should be called anytime noise_local_set_private is called */ void noise_remote_precompute(struct noise_remote *); /* Cryptographic functions */ int noise_create_initiation( struct noise_remote *, uint32_t *s_idx, uint8_t ue[NOISE_PUBLIC_KEY_LEN], uint8_t es[NOISE_PUBLIC_KEY_LEN + NOISE_AUTHTAG_LEN], uint8_t ets[NOISE_TIMESTAMP_LEN + NOISE_AUTHTAG_LEN]); int noise_consume_initiation( struct noise_local *, struct noise_remote **, uint32_t s_idx, uint8_t ue[NOISE_PUBLIC_KEY_LEN], uint8_t es[NOISE_PUBLIC_KEY_LEN + NOISE_AUTHTAG_LEN], uint8_t ets[NOISE_TIMESTAMP_LEN + NOISE_AUTHTAG_LEN]); int noise_create_response( struct noise_remote *, uint32_t *s_idx, uint32_t *r_idx, uint8_t ue[NOISE_PUBLIC_KEY_LEN], uint8_t en[0 + NOISE_AUTHTAG_LEN]); int noise_consume_response( struct noise_remote *, uint32_t s_idx, uint32_t r_idx, uint8_t ue[NOISE_PUBLIC_KEY_LEN], uint8_t en[0 + NOISE_AUTHTAG_LEN]); int noise_remote_begin_session(struct noise_remote *); void noise_remote_clear(struct noise_remote *); void noise_remote_expire_current(struct noise_remote *); int noise_remote_ready(struct noise_remote *); int noise_remote_encrypt( struct noise_remote *, uint32_t *r_idx, uint64_t *nonce, uint8_t *buf, size_t buflen); int noise_remote_decrypt( struct noise_remote *, uint32_t r_idx, uint64_t nonce, uint8_t *buf, size_t buflen); #ifdef WGTEST void noise_test(); #endif /* WGTEST */ #endif /* __NOISE_H__ */