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Comparing gvpe/src/connection.C (file contents):
Revision 1.96 by root, Thu Mar 24 21:52:48 2011 UTC vs.
Revision 1.113 by root, Thu Jan 29 00:21:39 2015 UTC

1/* 1/*
2 connection.C -- manage a single connection 2 connection.C -- manage a single connection
3 Copyright (C) 2003-2008,2010,2011 Marc Lehmann <gvpe@schmorp.de> 3 Copyright (C) 2003-2008,2010,2011,2013 Marc Lehmann <gvpe@schmorp.de>
4 4
5 This file is part of GVPE. 5 This file is part of GVPE.
6 6
7 GVPE is free software; you can redistribute it and/or modify it 7 GVPE is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the 8 under the terms of the GNU General Public License as published by the
… …
33 33
34#include <list> 34#include <list>
35#include <queue> 35#include <queue>
36#include <utility> 36#include <utility>
37 37
38#include <openssl/opensslv.h>
38#include <openssl/rand.h> 39#include <openssl/rand.h>
39#include <openssl/evp.h> 40#include <openssl/evp.h>
40#include <openssl/rsa.h> 41#include <openssl/rsa.h>
41#include <openssl/err.h> 42#include <openssl/err.h>
43
44// openssl 0.9.8 compatibility
45#if OPENSSL_VERSION_NUMBER < 0x10100000
46 #define require101(exp) exp
47#else
48 #define require101(exp) require (exp)
49#endif
42 50
43#include "conf.h" 51#include "conf.h"
44#include "slog.h" 52#include "slog.h"
45#include "device.h" 53#include "device.h"
46#include "vpn.h" 54#include "vpn.h"
47#include "connection.h" 55#include "connection.h"
56#include "hkdf.h"
48 57
49#include "netcompat.h" 58#include "netcompat.h"
50 59
51#if !HAVE_RAND_PSEUDO_BYTES
52# define RAND_pseudo_bytes RAND_bytes
53#endif
54
55#define MAGIC_OLD "vped\xbd\xc6\xdb\x82" // 8 bytes of magic (still used in the protocol)
56#define MAGIC "gvpe\xbd\xc6\xdb\x82" // 8 bytes of magic (understood but not generated) 60#define MAGIC "gvpe\xbd\xc6\xdb\x82" // 8 bytes of magic
57 61
58#define ULTRA_FAST 1 62#define ULTRA_FAST 1
59#define HLOG 15 63#define HLOG 15
60#include "lzf/lzf.h" 64#include "lzf/lzf.h"
61#include "lzf/lzf_c.c" 65#include "lzf/lzf_c.c"
… …
108struct crypto_ctx 112struct crypto_ctx
109{ 113{
110 EVP_CIPHER_CTX cctx; 114 EVP_CIPHER_CTX cctx;
111 HMAC_CTX hctx; 115 HMAC_CTX hctx;
112 116
113 crypto_ctx (const rsachallenge &challenge, int enc); 117 crypto_ctx (const auth_data &auth1, const auth_data &auth2, const ecdh_key &a, const ecdh_key &b, int enc);
114 ~crypto_ctx (); 118 ~crypto_ctx ();
115}; 119};
116 120
117crypto_ctx::crypto_ctx (const rsachallenge &challenge, int enc) 121crypto_ctx::crypto_ctx (const auth_data &auth1, const auth_data &auth2, const ecdh_key &a, const ecdh_key &b, int enc)
118{ 122{
123 ecdh_key s;
124
125 curve25519_combine (a, b, s);
126
127 {
128 u8 mac_key[MAC_KEYSIZE];
129 static const unsigned char mac_info[] = "gvpe mac key";
130
131 hkdf kdf (auth2.rsa.hkdf_salt, sizeof (auth2.rsa.hkdf_salt), HKDF_XTR_HASH ());
132 kdf.extract (auth1.rsa.mac_key, sizeof (auth1.rsa.mac_key));
133 kdf.extract (s, sizeof (s));
134 kdf.extract_done (HKDF_PRF_HASH ());
135 kdf.expand (mac_key, sizeof (mac_key), mac_info, sizeof (mac_info));
136
137 HMAC_CTX_init (&hctx);
138 require101 (HMAC_Init_ex (&hctx, mac_key, MAC_KEYSIZE, MAC_DIGEST (), 0));
139 }
140
141 {
142 u8 cipher_key[CIPHER_KEYSIZE];
143 static const unsigned char cipher_info[] = "gvpe cipher key";
144
145 hkdf kdf (auth2.rsa.hkdf_salt, sizeof (auth2.rsa.hkdf_salt), HKDF_XTR_HASH ());
146 kdf.extract (auth1.rsa.cipher_key, sizeof (auth1.rsa.cipher_key));
147 kdf.extract (s, sizeof (s));
148 kdf.extract_done (HKDF_PRF_HASH ());
149 kdf.expand (cipher_key, sizeof (cipher_key), cipher_info, sizeof (cipher_info));
150
119 EVP_CIPHER_CTX_init (&cctx); 151 EVP_CIPHER_CTX_init (&cctx);
120 require (EVP_CipherInit_ex (&cctx, CIPHER, 0, &challenge[CHG_CIPHER_KEY], 0, enc)); 152 require (EVP_CipherInit_ex (&cctx, CIPHER (), 0, cipher_key, 0, enc));
121 HMAC_CTX_init (&hctx); 153 }
122 HMAC_Init_ex (&hctx, &challenge[CHG_HMAC_KEY], HMAC_KEYLEN, DIGEST, 0);
123} 154}
124 155
125crypto_ctx::~crypto_ctx () 156crypto_ctx::~crypto_ctx ()
126{ 157{
127 require (EVP_CIPHER_CTX_cleanup (&cctx)); 158 require (EVP_CIPHER_CTX_cleanup (&cctx));
128 HMAC_CTX_cleanup (&hctx); 159 HMAC_CTX_cleanup (&hctx);
129} 160}
130 161
162static inline void
163auth_encrypt (RSA *key, const auth_data &auth, auth_encr &encr)
164{
165 if (RSA_public_encrypt (sizeof (auth.rsa),
166 (unsigned char *)&auth.rsa, (unsigned char *)&encr.rsa,
167 key, RSA_PKCS1_OAEP_PADDING) < 0)
168 fatal ("RSA_public_encrypt error");
169
170 memcpy (&encr.ecdh, &auth.ecdh, sizeof (encr.ecdh));
171}
172
173static inline bool
174auth_decrypt (RSA *key, const auth_encr &encr, auth_data &auth)
175{
176 u8 rsa_decrypt[RSA_KEYLEN];
177
178 if (RSA_private_decrypt (sizeof (encr.rsa),
179 (const unsigned char *)&encr.rsa, (unsigned char *)rsa_decrypt,
180 key, RSA_PKCS1_OAEP_PADDING) != sizeof (auth.rsa))
181 return 0;
182
183 memcpy (&auth.rsa, rsa_decrypt, sizeof (auth.rsa));
184 memcpy (&auth.ecdh, &encr.ecdh, sizeof (auth.ecdh));
185
186 return 1;
187}
188
131static void 189static void
132rsa_hash (const rsaid &id, const rsachallenge &chg, rsaresponse &h) 190auth_hash (const auth_data &auth, const ecdh_key &b, auth_mac &mac)
133{ 191{
134 EVP_MD_CTX ctx; 192 hkdf kdf (b, sizeof b, AUTH_DIGEST ()); // use response ecdh b as salt
135 193 kdf.extract (&auth.rsa, sizeof (auth.rsa));
136 EVP_MD_CTX_init (&ctx); 194 kdf.extract_done ();
137 require (EVP_DigestInit (&ctx, RSA_HASH)); 195 kdf.expand (mac, sizeof mac, auth.ecdh, sizeof (auth.ecdh)); // use challenge ecdh b as info
138 require (EVP_DigestUpdate (&ctx, &chg, sizeof chg));
139 require (EVP_DigestUpdate (&ctx, &id, sizeof id));
140 require (EVP_DigestFinal (&ctx, (unsigned char *)&h, 0));
141 EVP_MD_CTX_cleanup (&ctx);
142} 196}
143 197
144struct rsa_entry 198void
199connection::generate_auth_data ()
145{ 200{
146 tstamp expire; 201 if (auth_expire < ev_now ())
147 rsaid id;
148 rsachallenge chg;
149};
150
151struct rsa_cache : list<rsa_entry>
152{
153 inline void cleaner_cb (ev::timer &w, int revents); ev::timer cleaner;
154
155 bool find (const rsaid &id, rsachallenge &chg)
156 {
157 for (iterator i = begin (); i != end (); ++i)
158 { 202 {
159 if (!memcmp (&id, &i->id, sizeof id) && i->expire > ev_now ()) 203 // request data
160 { 204 rand_fill (snd_auth.rsa);
161 memcpy (&chg, &i->chg, sizeof chg); 205 curve25519_generate (snd_ecdh_a, snd_auth.ecdh);
162 206
163 erase (i); 207 // eventual response data
164 return true; 208 curve25519_generate (rcv_ecdh_a, rcv_ecdh_b);
165 }
166 } 209 }
167 210
168 if (!cleaner.is_active ()) 211 // every use prolongs the expiry
169 cleaner.again ();
170
171 return false;
172 }
173
174 void gen (rsaid &id, rsachallenge &chg)
175 {
176 rsa_entry e;
177
178 RAND_bytes ((unsigned char *)&id, sizeof id);
179 RAND_bytes ((unsigned char *)&chg, sizeof chg);
180
181 e.expire = ev_now () + RSA_TTL; 212 auth_expire = ev_now () + AUTH_TTL;
182 e.id = id;
183 memcpy (&e.chg, &chg, sizeof chg);
184
185 push_back (e);
186
187 if (!cleaner.is_active ())
188 cleaner.again ();
189 }
190
191 rsa_cache ()
192 {
193 cleaner.set<rsa_cache, &rsa_cache::cleaner_cb> (this);
194 cleaner.set (RSA_TTL, RSA_TTL);
195 }
196
197} rsa_cache;
198
199void
200rsa_cache::cleaner_cb (ev::timer &w, int revents)
201{
202 if (empty ())
203 w.stop ();
204 else
205 {
206 for (iterator i = begin (); i != end (); )
207 if (i->expire <= ev_now ())
208 i = erase (i);
209 else
210 ++i;
211 }
212} 213}
213 214
214////////////////////////////////////////////////////////////////////////////// 215//////////////////////////////////////////////////////////////////////////////
215 216
216pkt_queue::pkt_queue (double max_ttl, int max_queue) 217pkt_queue::pkt_queue (double max_ttl, int max_queue)
… …
365 } 366 }
366} 367}
367 368
368///////////////////////////////////////////////////////////////////////////// 369/////////////////////////////////////////////////////////////////////////////
369 370
370unsigned char hmac_packet::hmac_digest[EVP_MAX_MD_SIZE];
371
372void 371void
373hmac_packet::hmac_gen (crypto_ctx *ctx) 372hmac_packet::hmac_gen (crypto_ctx *ctx, u8 *hmac_digest)
374{ 373{
375 unsigned int xlen;
376
377 HMAC_CTX *hctx = &ctx->hctx; 374 HMAC_CTX *hctx = &ctx->hctx;
378 375
379 HMAC_Init_ex (hctx, 0, 0, 0, 0); 376 require101 (HMAC_Init_ex (hctx, 0, 0, 0, 0));
380 HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet), 377 require101 (HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet), len - sizeof (hmac_packet)));
381 len - sizeof (hmac_packet)); 378 require101 (HMAC_Final (hctx, hmac_digest, 0));
382 HMAC_Final (hctx, (unsigned char *) &hmac_digest, &xlen);
383} 379}
384 380
385void 381void
386hmac_packet::hmac_set (crypto_ctx *ctx) 382hmac_packet::hmac_set (crypto_ctx *ctx)
387{ 383{
388 hmac_gen (ctx); 384 unsigned char hmac_digest[EVP_MAX_MD_SIZE];
389 385 hmac_gen (ctx, hmac_digest);
390 memcpy (hmac, hmac_digest, HMACLENGTH); 386 memcpy (hmac, hmac_digest, HMACLENGTH);
391} 387}
392 388
393bool 389bool
394hmac_packet::hmac_chk (crypto_ctx *ctx) 390hmac_packet::hmac_chk (crypto_ctx *ctx)
395{ 391{
396 hmac_gen (ctx); 392 unsigned char hmac_digest[EVP_MAX_MD_SIZE];
397 393 hmac_gen (ctx, hmac_digest);
398 return !memcmp (hmac, hmac_digest, HMACLENGTH); 394 return slow_memeq (hmac, hmac_digest, HMACLENGTH);
399} 395}
400 396
401void 397void
402vpn_packet::set_hdr (ptype type_, unsigned int dst) 398vpn_packet::set_hdr (ptype type_, unsigned int dst)
403{ 399{
… …
409 srcdst = ((src >> 8) << 4) | (dst >> 8); 405 srcdst = ((src >> 8) << 4) | (dst >> 8);
410 dst1 = dst; 406 dst1 = dst;
411} 407}
412 408
413#define MAXVPNDATA (MAX_MTU - 6 - 6) 409#define MAXVPNDATA (MAX_MTU - 6 - 6)
414#define DATAHDR (sizeof (u32) + RAND_SIZE)
415 410
416struct vpndata_packet : vpn_packet 411struct vpndata_packet : vpn_packet
417{ 412{
418 u8 data[MAXVPNDATA + DATAHDR]; // seqno 413 u32 ctr; // seqno
414 u8 data[MAXVPNDATA];
419 415
420 void setup (connection *conn, int dst, u8 *d, u32 len, u32 seqno); 416 void setup (connection *conn, int dst, u8 *d, u32 len, u32 seqno);
421 tap_packet *unpack (connection *conn, u32 &seqno); 417 tap_packet *unpack (connection *conn, u32 &seqno);
422 418
423private: 419private:
424 const u32 data_hdr_size () const 420 const u32 data_hdr_size () const
425 { 421 {
426 return sizeof (vpndata_packet) - sizeof (net_packet) - MAXVPNDATA - DATAHDR; 422 // the distance from beginning of packet to data member
423 return data - at (0);
427 } 424 }
428}; 425};
426
427// expands packet counter (unlike seqno, in network byte order) to counter mode IV
428static unsigned char *
429expand_iv (u32 ctr)
430{
431 static u32 iv[IV_SIZE (CIPHER) / 4];
432
433 require (sizeof (iv) == 4 * 4);
434 require (IV_SIZE (CIPHER) % 4 == 0);
435
436 iv[0] =
437 iv[1] =
438 iv[2] = ctr;
439
440 // I would reuse ctr here to to avoid potential endianness issues,
441 // but it seems openssl wraps around. While this would be still ok,
442 // and I don't even know if its true, let's play safe and initialise
443 // to 0.
444 iv[3] = 0;
445
446 return (unsigned char *)iv;
447}
429 448
430void 449void
431vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno) 450vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno)
432{ 451{
433 EVP_CIPHER_CTX *cctx = &conn->octx->cctx; 452 EVP_CIPHER_CTX *cctx = &conn->octx->cctx;
… …
451 d[1] = cl; 470 d[1] = cl;
452 } 471 }
453 } 472 }
454#endif 473#endif
455 474
475 ctr = htonl (seqno);
476
456 require (EVP_EncryptInit_ex (cctx, 0, 0, 0, 0)); 477 require (EVP_EncryptInit_ex (cctx, 0, 0, 0, expand_iv (ctr)));
457
458 struct {
459#if RAND_SIZE
460 u8 rnd[RAND_SIZE];
461#endif
462 u32 seqno;
463 } datahdr;
464
465 datahdr.seqno = ntohl (seqno);
466#if RAND_SIZE
467 RAND_pseudo_bytes ((unsigned char *) datahdr.rnd, RAND_SIZE);
468#endif
469 478
470 require (EVP_EncryptUpdate (cctx, 479 require (EVP_EncryptUpdate (cctx,
471 (unsigned char *) data + outl, &outl2, 480 (unsigned char *)data + outl, &outl2,
472 (unsigned char *) &datahdr, DATAHDR)); 481 (unsigned char *)d, l));
473 outl += outl2; 482 outl += outl2;
474 483
475 require (EVP_EncryptUpdate (cctx, 484 // it seems this is a nop for us, but we do it anyways
476 (unsigned char *) data + outl, &outl2, 485 require (EVP_EncryptFinal_ex (cctx, (unsigned char *)data + outl, &outl2));
477 (unsigned char *) d, l));
478 outl += outl2; 486 outl += outl2;
479 487
480 require (EVP_EncryptFinal_ex (cctx, (unsigned char *) data + outl, &outl2));
481 outl += outl2;
482
483 len = outl + data_hdr_size (); 488 len = data_hdr_size () + outl;
484 489
485 set_hdr (type, dst); 490 set_hdr (type, dst);
486 491
487 hmac_set (conn->octx); 492 hmac_set (conn->octx);
488} 493}
… …
492{ 497{
493 EVP_CIPHER_CTX *cctx = &conn->ictx->cctx; 498 EVP_CIPHER_CTX *cctx = &conn->ictx->cctx;
494 int outl = 0, outl2; 499 int outl = 0, outl2;
495 tap_packet *p = new tap_packet; 500 tap_packet *p = new tap_packet;
496 u8 *d; 501 u8 *d;
497 u32 l = len - data_hdr_size ();
498 502
503 seqno = ntohl (ctr);
504
499 require (EVP_DecryptInit_ex (cctx, 0, 0, 0, 0)); 505 require (EVP_DecryptInit_ex (cctx, 0, 0, 0, expand_iv (ctr)));
500 506
501#if ENABLE_COMPRESSION 507#if ENABLE_COMPRESSION
502 u8 cdata[MAX_MTU]; 508 u8 cdata[MAX_MTU];
503 509
504 if (type == PT_DATA_COMPRESSED) 510 if (type == PT_DATA_COMPRESSED)
505 d = cdata; 511 d = cdata;
506 else 512 else
507#endif 513#endif
508 d = &(*p)[6 + 6 - DATAHDR]; 514 d = &(*p)[6 + 6];
509 515
510 /* this overwrites part of the src mac, but we fix that later */ 516 // this can overwrite the len/dst/src fields
511 require (EVP_DecryptUpdate (cctx, 517 require (EVP_DecryptUpdate (cctx,
512 d, &outl2, 518 d, &outl2,
513 (unsigned char *)&data, len - data_hdr_size ())); 519 (unsigned char *)&data, len - data_hdr_size ()));
514 outl += outl2; 520 outl += outl2;
515 521
522 // it seems this is a nop for us, but we do it anyways
516 require (EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2)); 523 require (EVP_DecryptFinal_ex (cctx, (unsigned char *)d + outl, &outl2));
517 outl += outl2; 524 outl += outl2;
518 525
519 seqno = ntohl (*(u32 *)(d + RAND_SIZE));
520
521 id2mac (dst () ? dst() : THISNODE->id, p->dst); 526 id2mac (dst () ? dst() : THISNODE->id, p->dst);
522 id2mac (src (), p->src); 527 id2mac (src (), p->src);
523 528
524#if ENABLE_COMPRESSION 529#if ENABLE_COMPRESSION
525 if (type == PT_DATA_COMPRESSED) 530 if (type == PT_DATA_COMPRESSED)
526 { 531 {
527 u32 cl = (d[DATAHDR] << 8) | d[DATAHDR + 1]; 532 u32 cl = (d[0] << 8) | d[1];
528 533
529 p->len = lzf_decompress (d + DATAHDR + 2, cl < MAX_MTU ? cl : 0, 534 p->len = lzf_decompress (d + 2, cl < MAX_MTU - 2 ? cl : 0,
530 &(*p)[6 + 6], MAX_MTU) 535 &(*p)[6 + 6], MAX_MTU)
531 + 6 + 6; 536 + 6 + 6;
532 } 537 }
533 else 538 else
534 p->len = outl + (6 + 6 - DATAHDR); 539 p->len = outl + (6 + 6);
535#endif 540#endif
536 541
537 return p; 542 return p;
538} 543}
539 544
… …
546 } 551 }
547}; 552};
548 553
549struct config_packet : vpn_packet 554struct config_packet : vpn_packet
550{ 555{
551 // actually, hmaclen cannot be checked because the hmac 556 u8 serial[SERIAL_SIZE];
552 // field comes before this data, so peers with other
553 // hmacs simply will not work.
554 u8 prot_major, prot_minor, randsize, hmaclen; 557 u8 prot_major, prot_minor, randsize;
555 u8 flags, challengelen, features, pad3; 558 u8 flags, features, pad6, pad7, pad8;
556 u32 cipher_nid, digest_nid, hmac_nid; 559 u32 cipher_nid, mac_nid, auth_nid;
557 560
558 void setup (ptype type, int dst); 561 void setup (ptype type, int dst);
559 bool chk_config () const; 562 bool chk_config (const conf_node *conf, const sockinfo &rsi) const;
560 563
561 static u8 get_features () 564 static u8 get_features ()
562 { 565 {
563 u8 f = 0; 566 u8 f = 0;
564#if ENABLE_COMPRESSION 567#if ENABLE_COMPRESSION
… …
577void 580void
578config_packet::setup (ptype type, int dst) 581config_packet::setup (ptype type, int dst)
579{ 582{
580 prot_major = PROTOCOL_MAJOR; 583 prot_major = PROTOCOL_MAJOR;
581 prot_minor = PROTOCOL_MINOR; 584 prot_minor = PROTOCOL_MINOR;
582 randsize = RAND_SIZE;
583 hmaclen = HMACLENGTH;
584 flags = 0; 585 flags = 0;
585 challengelen = sizeof (rsachallenge);
586 features = get_features (); 586 features = get_features ();
587 587
588 strncpy ((char *)serial, conf.serial, sizeof (serial));
589
588 cipher_nid = htonl (EVP_CIPHER_nid (CIPHER)); 590 cipher_nid = htonl (EVP_CIPHER_nid (CIPHER ()));
589 digest_nid = htonl (EVP_MD_type (RSA_HASH));
590 hmac_nid = htonl (EVP_MD_type (DIGEST)); 591 mac_nid = htonl (EVP_MD_type (MAC_DIGEST ()));
592 auth_nid = htonl (EVP_MD_type (AUTH_DIGEST ()));
591 593
592 len = sizeof (*this) - sizeof (net_packet); 594 len = sizeof (*this) - sizeof (net_packet);
593 set_hdr (type, dst); 595 set_hdr (type, dst);
594} 596}
595 597
596bool 598bool
597config_packet::chk_config () const 599config_packet::chk_config (const conf_node *conf, const sockinfo &rsi) const
598{ 600{
599 if (prot_major != PROTOCOL_MAJOR) 601 if (prot_major != PROTOCOL_MAJOR)
600 slog (L_WARN, _("major version mismatch (remote %d <=> local %d)"), prot_major, PROTOCOL_MAJOR); 602 slog (L_WARN, _("%s(%s): major version mismatch (remote %d <=> local %d)"),
601 else if (randsize != RAND_SIZE) 603 conf->nodename, (const char *)rsi, prot_major, PROTOCOL_MAJOR);
602 slog (L_WARN, _("rand size mismatch (remote %d <=> local %d)"), randsize, RAND_SIZE);
603 else if (hmaclen != HMACLENGTH)
604 slog (L_WARN, _("hmac length mismatch (remote %d <=> local %d)"), hmaclen, HMACLENGTH);
605 else if (challengelen != sizeof (rsachallenge))
606 slog (L_WARN, _("challenge length mismatch (remote %d <=> local %d)"), challengelen, sizeof (rsachallenge));
607 else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER))) 604 else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER ())))
608 slog (L_WARN, _("cipher mismatch (remote %x <=> local %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER)); 605 slog (L_WARN, _("%s(%s): cipher algo mismatch (remote %x <=> local %x)"),
609 else if (digest_nid != htonl (EVP_MD_type (RSA_HASH))) 606 conf->nodename, (const char *)rsi, ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER ()));
610 slog (L_WARN, _("digest mismatch (remote %x <=> local %x)"), ntohl (digest_nid), EVP_MD_type (RSA_HASH));
611 else if (hmac_nid != htonl (EVP_MD_type (DIGEST))) 607 else if (mac_nid != htonl (EVP_MD_type (MAC_DIGEST ())))
612 slog (L_WARN, _("hmac mismatch (remote %x <=> local %x)"), ntohl (hmac_nid), EVP_MD_type (DIGEST)); 608 slog (L_WARN, _("%s(%s): mac algo mismatch (remote %x <=> local %x)"),
609 conf->nodename, (const char *)rsi, ntohl (mac_nid), EVP_MD_type (MAC_DIGEST ()));
610 else if (auth_nid != htonl (EVP_MD_type (AUTH_DIGEST ())))
611 slog (L_WARN, _("%s(%s): auth algo mismatch (remote %x <=> local %x)"),
612 conf->nodename, (const char *)rsi, ntohl (auth_nid), EVP_MD_type (AUTH_DIGEST ()));
613 else 613 else
614 {
615 int cmp = memcmp (serial, ::conf.serial, sizeof (serial));
616
617 if (cmp > 0)
618 slog (L_WARN, _("%s(%s): remote serial newer than local serial - outdated config?"),
619 conf->nodename, (const char *)rsi);
620 else if (cmp == 0)
614 return true; 621 return true;
622 }
615 623
616 return false; 624 return false;
617} 625}
618 626
619struct auth_req_packet : config_packet 627struct auth_req_packet : config_packet // UNPROTECTED
620{ 628{
621 char magic[8]; 629 char magic[8];
622 u8 initiate; // false if this is just an automatic reply 630 u8 initiate; // false if this is just an automatic reply
623 u8 protocols; // supported protocols (will be patched on forward) 631 u8 protocols; // supported protocols (will be patched on forward)
624 u8 pad2, pad3; 632 u8 pad2, pad3;
625 rsaid id; 633 auth_encr encr;
626 rsaencrdata encr;
627 634
628 auth_req_packet (int dst, bool initiate_, u8 protocols_) 635 auth_req_packet (int dst, bool initiate_, u8 protocols_)
629 { 636 {
630 config_packet::setup (PT_AUTH_REQ, dst); 637 config_packet::setup (PT_AUTH_REQ, dst);
631 strncpy (magic, MAGIC_OLD, 8); 638 memcpy (magic, MAGIC, 8);
632 initiate = !!initiate_; 639 initiate = !!initiate_;
633 protocols = protocols_; 640 protocols = protocols_;
634 641
635 len = sizeof (*this) - sizeof (net_packet); 642 len = sizeof (*this) - sizeof (net_packet);
636 } 643 }
637}; 644};
638 645
639struct auth_res_packet : config_packet 646struct auth_res_packet : vpn_packet // UNPROTECTED
640{ 647{
641 rsaid id;
642 u8 pad1, pad2, pad3;
643 u8 response_len; // encrypted length
644 rsaresponse response; 648 auth_response response;
645 649
646 auth_res_packet (int dst) 650 auth_res_packet (int dst)
647 { 651 {
648 config_packet::setup (PT_AUTH_RES, dst); 652 set_hdr (PT_AUTH_RES, dst);
649 653
650 len = sizeof (*this) - sizeof (net_packet); 654 len = sizeof (*this) - sizeof (net_packet);
651 } 655 }
652}; 656};
653 657
… …
683}; 687};
684 688
685///////////////////////////////////////////////////////////////////////////// 689/////////////////////////////////////////////////////////////////////////////
686 690
687void 691void
688connection::connection_established () 692connection::connection_established (const sockinfo &rsi)
689{ 693{
690 slog (L_NOISE, _("%s: possible connection establish (ictx %d, octx %d)"), conf->nodename, !!ictx, !!octx); 694 if (!have_snd_auth || !have_rcv_auth)
695 return;
691 696
692 if (ictx && octx) 697 si = rsi;
698 protocol = rsi.prot;
699
700 slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."),
701 conf->nodename, (const char *)rsi,
702 vpn->can_direct (THISNODE, conf) ? "direct" : "forwarded",
703 PROTOCOL_MAJOR, prot_minor);
704
705 if (::conf.script_node_up)
706 {
707 run_script_cb *cb = new run_script_cb;
708 cb->set<connection, &connection::script_node_up> (this);
709 run_script_queued (cb, _("node-up command execution failed, continuing."));
693 { 710 }
711
712 delete ictx; ictx = new crypto_ctx (rcv_auth, snd_auth, rcv_ecdh_a, rcv_auth.ecdh, 0);
713 iseqno.reset (ntohl (rcv_auth.rsa.seqno) & 0x7fffffff);
714
715 delete octx; octx = new crypto_ctx (snd_auth, rcv_auth, snd_ecdh_a, snd_ecdh_b , 1);
716 oseqno = ntohl (snd_auth.rsa.seqno) & 0x7fffffff;
717
694 // make sure rekeying timeouts are slightly asymmetric 718 // make sure rekeying timeouts are slightly asymmetric
695 ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0); 719 ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0);
696 rekey.start (rekey_interval, rekey_interval); 720 rekey.start (rekey_interval, rekey_interval);
721
722 hmac_error = 0.;
723
697 keepalive.start (::conf.keepalive); 724 keepalive.start (::conf.keepalive);
698 725
699 // send queued packets 726 // send queued packets
700 if (ictx && octx)
701 {
702 while (tap_packet *p = (tap_packet *)data_queue.get ()) 727 while (tap_packet *p = (tap_packet *)data_queue.get ())
703 { 728 {
704 if (p->len) send_data_packet (p); 729 if (p->len) send_data_packet (p);
705 delete p; 730 delete p;
706 } 731 }
707 732
708 while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) 733 while (vpn_packet *p = (vpn_packet *)vpn_queue.get ())
709 { 734 {
710 if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY); 735 if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY);
711 delete p; 736 delete p;
712 } 737 }
713 }
714 738
715 vpn->connection_established (this); 739 vpn->connection_established (this);
716 }
717 else
718 {
719 retry_cnt = 0;
720 establish_connection.start (5);
721 keepalive.stop ();
722 rekey.stop ();
723 }
724} 740}
725 741
726void 742void
727connection::reset_si () 743connection::reset_si ()
728{ 744{
… …
733 slog (L_TRACE, _("%s: direct connection denied by config."), conf->nodename); 749 slog (L_TRACE, _("%s: direct connection denied by config."), conf->nodename);
734 protocol = 0; 750 protocol = 0;
735 } 751 }
736 752
737 si.set (conf, protocol); 753 si.set (conf, protocol);
738
739 is_direct = si.valid ();
740} 754}
741 755
742// ensure sockinfo is valid, forward if necessary 756// ensure sockinfo is valid, forward if necessary
743const sockinfo & 757const sockinfo &
744connection::forward_si (const sockinfo &si) const 758connection::forward_si (const sockinfo &si) const
… …
763 777
764void 778void
765connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos) 779connection::send_vpn_packet (vpn_packet *pkt, const sockinfo &si, int tos)
766{ 780{
767 if (!vpn->send_vpn_packet (pkt, si, tos)) 781 if (!vpn->send_vpn_packet (pkt, si, tos))
768 reset_connection (); 782 reset_connection ("packet send error");
769} 783}
770 784
771void 785void
772connection::send_ping (const sockinfo &si, u8 pong) 786connection::send_ping (const sockinfo &si, u8 pong)
773{ 787{
774 ping_packet *pkt = new ping_packet; 788 ping_packet *pkt = new ping_packet;
775 789
776 pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); 790 pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING);
777 791
778 slog (L_TRACE, "%s << %s [%s]", conf->nodename, pong ? "PT_PONG" : "PT_PING", (const char *)si); 792 slog (L_TRACE, "%s << %s [%s]", conf->nodename, pong ? "PT_PONG" : "PT_PING", (const char *)si);
779
780 send_vpn_packet (pkt, si, IPTOS_LOWDELAY); 793 send_vpn_packet (pkt, si, IPTOS_LOWDELAY);
781 794
782 delete pkt; 795 delete pkt;
783} 796}
784 797
… …
799void 812void
800connection::send_auth_request (const sockinfo &si, bool initiate) 813connection::send_auth_request (const sockinfo &si, bool initiate)
801{ 814{
802 auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols); 815 auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols);
803 816
804 rsachallenge chg; 817 generate_auth_data ();
805 rsa_cache.gen (pkt->id, chg);
806 rsa_encrypt (conf->rsa_key, chg, pkt->encr); 818 auth_encrypt (conf->rsa_key, snd_auth, pkt->encr);
807 819
808 slog (L_TRACE, "%s << PT_AUTH_REQ [%s]", conf->nodename, (const char *)si); 820 slog (L_TRACE, "%s << PT_AUTH_REQ [%s]", conf->nodename, (const char *)si);
809
810 send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly 821 send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly
811 822
812 delete pkt; 823 delete pkt;
813} 824}
814 825
815void 826void
816connection::send_auth_response (const sockinfo &si, const rsaid &id, const rsachallenge &chg) 827connection::send_auth_response (const sockinfo &si)
817{ 828{
818 auth_res_packet *pkt = new auth_res_packet (conf->id); 829 auth_res_packet *pkt = new auth_res_packet (conf->id);
819 830
820 pkt->id = id; 831 memcpy (pkt->response.ecdh, rcv_ecdh_b, sizeof rcv_ecdh_b);
821 832 auth_hash (rcv_auth, rcv_ecdh_b, pkt->response.mac);
822 rsa_hash (id, chg, pkt->response);
823
824 pkt->hmac_set (octx);
825 833
826 slog (L_TRACE, "%s << PT_AUTH_RES [%s]", conf->nodename, (const char *)si); 834 slog (L_TRACE, "%s << PT_AUTH_RES [%s]", conf->nodename, (const char *)si);
827
828 send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly 835 send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly
829 836
830 delete pkt; 837 delete pkt;
831} 838}
832 839
… …
856 { 863 {
857 // a bit hacky, if ondemand, and packets are no longer queued, then reset the connection 864 // a bit hacky, if ondemand, and packets are no longer queued, then reset the connection
858 // and stop trying. should probably be handled by a per-connection expire handler. 865 // and stop trying. should probably be handled by a per-connection expire handler.
859 if (connectmode == conf_node::C_ONDEMAND && vpn_queue.empty () && data_queue.empty ()) 866 if (connectmode == conf_node::C_ONDEMAND && vpn_queue.empty () && data_queue.empty ())
860 { 867 {
861 reset_connection (); 868 reset_connection ("no demand");
862 return; 869 return;
863 } 870 }
864 871
865 last_establish_attempt = ev_now (); 872 last_establish_attempt = ev_now ();
866 873
… …
868 ? (retry_cnt & 3) + 1 875 ? (retry_cnt & 3) + 1
869 : 1 << (retry_cnt >> 2)); 876 : 1 << (retry_cnt >> 2));
870 877
871 reset_si (); 878 reset_si ();
872 879
873 bool slow = si.prot & PROT_SLOW; 880 bool slow = (si.prot & PROT_SLOW) || (conf->low_power || THISNODE->low_power);
874 881
875 if (si.prot && !si.host && vpn->can_direct (THISNODE, conf)) 882 if (si.prot && !si.host && vpn->can_direct (THISNODE, conf))
876 { 883 {
877 /*TODO*/ /* start the timer so we don't recurse endlessly */ 884 /*TODO*/ /* start the timer so we don't recurse endlessly */
878 w.start (1); 885 w.start (1);
… …
888 895
889 slow = slow || (dsi.prot & PROT_SLOW); 896 slow = slow || (dsi.prot & PROT_SLOW);
890 897
891 if (dsi.valid () && auth_rate_limiter.can (dsi)) 898 if (dsi.valid () && auth_rate_limiter.can (dsi))
892 { 899 {
893 if (retry_cnt < 4) 900 // use ping after the first few retries
901 // TODO: on rekeys, the other node might not interpret ping correctly,
902 // TODO: as it will still have a valid connection
903 if (retry_cnt < 4 && (!conf->low_power || THISNODE->low_power))
894 send_auth_request (dsi, true); 904 send_auth_request (dsi, true);
895 else 905 else
896 send_ping (dsi, 0); 906 send_ping (dsi, 0);
897 } 907 }
898 } 908 }
899 909
900 retry_int *= slow ? 8. : 0.9; 910 retry_int *= slow ? 4. : 0.9;
901 911
902 if (retry_int < conf->max_retry) 912 if (retry_int < conf->max_retry)
903 retry_cnt++; 913 retry_cnt++;
904 else 914 else
905 retry_int = conf->max_retry; 915 retry_int = conf->max_retry;
… …
907 w.start (retry_int); 917 w.start (retry_int);
908 } 918 }
909} 919}
910 920
911void 921void
912connection::reset_connection () 922connection::reset_connection (const char *reason)
913{ 923{
914 if (ictx && octx) 924 if (ictx && octx)
915 { 925 {
916 slog (L_INFO, _("%s(%s): connection lost"), 926 slog (L_INFO, _("%s(%s): connection lost (%s)"),
917 conf->nodename, (const char *)si); 927 conf->nodename, (const char *)si, reason);
918 928
919 if (::conf.script_node_down) 929 if (::conf.script_node_down)
920 { 930 {
921 run_script_cb *cb = new run_script_cb; 931 run_script_cb *cb = new run_script_cb;
922 cb->set<connection, &connection::script_node_down> (this); 932 cb->set<connection, &connection::script_node_down> (this);
… …
927 delete ictx; ictx = 0; 937 delete ictx; ictx = 0;
928 delete octx; octx = 0; 938 delete octx; octx = 0;
929 939
930 si.host = 0; 940 si.host = 0;
931 941
942 have_snd_auth = false;
943 have_rcv_auth = false;
944 auth_expire = 0.;
945
932 last_activity = 0.; 946 last_activity = 0.;
933 //last_si_change = 0.; 947 //last_si_change = 0.;
934 retry_cnt = 0; 948 retry_cnt = 0;
935 949
936 rekey.stop (); 950 rekey.stop ();
… …
942connection::shutdown () 956connection::shutdown ()
943{ 957{
944 if (ictx && octx) 958 if (ictx && octx)
945 send_reset (si); 959 send_reset (si);
946 960
947 reset_connection (); 961 reset_connection ("shutdown");
948} 962}
949 963
950// poor-man's rekeying 964// poor-man's rekeying
951inline void 965inline void
952connection::rekey_cb (ev::timer &w, int revents) 966connection::rekey_cb (ev::timer &w, int revents)
953{ 967{
954 reset_connection (); 968 reset_connection ("rekeying");
955 establish_connection (); 969 establish_connection ();
956} 970}
957 971
958void 972void
959connection::send_data_packet (tap_packet *pkt) 973connection::send_data_packet (tap_packet *pkt)
… …
976 990
977void 991void
978connection::post_inject_queue () 992connection::post_inject_queue ()
979{ 993{
980 // force a connection every now and when when packets are sent (max 1/s) 994 // force a connection every now and when when packets are sent (max 1/s)
981 if (ev_now () - last_establish_attempt >= 0.95) // arbitrary 995 if (ev_now () - last_establish_attempt >= (conf->low_power || THISNODE->low_power ? 2.95 : 0.95)) // arbitrary
982 establish_connection.stop (); 996 establish_connection.stop ();
983 997
984 establish_connection (); 998 establish_connection ();
985} 999}
986 1000
… …
1046 // about our desire for communication. 1060 // about our desire for communication.
1047 establish_connection (); 1061 establish_connection ();
1048 break; 1062 break;
1049 1063
1050 case vpn_packet::PT_RESET: 1064 case vpn_packet::PT_RESET:
1065 slog (L_TRACE, "%s >> PT_RESET", conf->nodename);
1066
1067 if (ictx && octx)
1051 { 1068 {
1052 reset_connection (); 1069 reset_connection ("remote reset");
1053 1070
1054 config_packet *p = (config_packet *) pkt; 1071 config_packet *p = (config_packet *) pkt;
1055 1072
1056 if (!p->chk_config ()) 1073 if (p->chk_config (conf, rsi) && connectmode == conf_node::C_ALWAYS)
1057 {
1058 slog (L_WARN, _("%s(%s): protocol mismatch, disabling node."),
1059 conf->nodename, (const char *)rsi);
1060 connectmode = conf_node::C_DISABLED;
1061 }
1062 else if (connectmode == conf_node::C_ALWAYS)
1063 establish_connection (); 1074 establish_connection ();
1064 } 1075 }
1076
1065 break; 1077 break;
1066 1078
1067 case vpn_packet::PT_AUTH_REQ: 1079 case vpn_packet::PT_AUTH_REQ:
1068 if (auth_rate_limiter.can (rsi)) 1080 if (auth_rate_limiter.can (rsi))
1069 { 1081 {
… …
1071 1083
1072 slog (L_TRACE, "%s >> PT_AUTH_REQ(%s,p%02x,f%02x)", 1084 slog (L_TRACE, "%s >> PT_AUTH_REQ(%s,p%02x,f%02x)",
1073 conf->nodename, p->initiate ? "initiate" : "reply", 1085 conf->nodename, p->initiate ? "initiate" : "reply",
1074 p->protocols, p->features); 1086 p->protocols, p->features);
1075 1087
1088 if (memcmp (p->magic, MAGIC, 8))
1089 {
1090 slog (L_WARN, _("%s(%s): protocol magic mismatch - stray packet?"),
1091 conf->nodename, (const char *)rsi);
1092 }
1076 if (p->chk_config () 1093 else if (p->chk_config (conf, rsi))
1077 && (!memcmp (p->magic, MAGIC_OLD, 8) || !memcmp (p->magic, MAGIC, 8)))
1078 { 1094 {
1079 if (p->prot_minor != PROTOCOL_MINOR) 1095 if (p->prot_minor != PROTOCOL_MINOR)
1080 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), 1096 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
1081 conf->nodename, (const char *)rsi, 1097 conf->nodename, (const char *)rsi,
1082 PROTOCOL_MINOR, conf->nodename, p->prot_minor); 1098 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
1083 1099
1084 if (p->initiate) 1100 if (p->initiate)
1101 {
1085 send_auth_request (rsi, false); 1102 send_auth_request (rsi, false);
1086 1103
1087 rsachallenge k; 1104 if (ictx && octx)
1105 reset_connection ("reconnect");
1106 }
1088 1107
1108 auth_data auth;
1109
1089 if (!rsa_decrypt (::conf.rsa_key, p->encr, k)) 1110 if (!auth_decrypt (::conf.rsa_key, p->encr, auth))
1090 { 1111 {
1091 slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), 1112 slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"),
1092 conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); 1113 conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0));
1093 break;
1094 } 1114 }
1095 else 1115 else
1096 { 1116 {
1097 delete octx; 1117 bool chg = !have_rcv_auth || !slow_memeq (&rcv_auth, &auth, sizeof auth);
1098 1118
1099 octx = new crypto_ctx (k, 1); 1119 rcv_auth = auth;
1100 oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; 1120 have_rcv_auth = true;
1101 1121
1122 send_auth_response (rsi);
1123
1124 if (chg)
1125 {
1102 conf->protocols = p->protocols; 1126 conf->protocols = p->protocols;
1103 features = p->features & config_packet::get_features (); 1127 features = p->features & config_packet::get_features ();
1104 1128
1105 send_auth_response (rsi, p->id, k);
1106
1107 connection_established (); 1129 connection_established (rsi);
1108
1109 break; 1130 }
1110 } 1131 }
1132
1133 break;
1111 } 1134 }
1112 else
1113 slog (L_WARN, _("%s(%s): protocol mismatch."),
1114 conf->nodename, (const char *)rsi);
1115 1135
1116 send_reset (rsi); 1136 send_reset (rsi);
1117 } 1137 }
1118 1138
1119 break; 1139 break;
… …
1122 { 1142 {
1123 auth_res_packet *p = (auth_res_packet *)pkt; 1143 auth_res_packet *p = (auth_res_packet *)pkt;
1124 1144
1125 slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename); 1145 slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename);
1126 1146
1127 if (p->chk_config ()) 1147 auth_mac local_mac;
1148 auth_hash (snd_auth, p->response.ecdh, local_mac);
1149
1150 if (!slow_memeq (&p->response.mac, local_mac, sizeof local_mac))
1128 { 1151 {
1129 if (p->prot_minor != PROTOCOL_MINOR)
1130 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
1131 conf->nodename, (const char *)rsi,
1132 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
1133
1134 rsachallenge chg;
1135
1136 if (!rsa_cache.find (p->id, chg))
1137 {
1138 slog (L_ERR, _("%s(%s): unrequested auth response, ignoring."), 1152 slog (L_ERR, _("%s(%s): unrequested or outdated auth response, ignoring."),
1139 conf->nodename, (const char *)rsi); 1153 conf->nodename, (const char *)rsi);
1140 break;
1141 } 1154 }
1142 else 1155 else if (!have_snd_auth)
1143 { 1156 {
1144 crypto_ctx *cctx = new crypto_ctx (chg, 0); 1157 memcpy (snd_ecdh_b, p->response.ecdh, sizeof snd_ecdh_b);
1145 1158
1146 if (!p->hmac_chk (cctx)) 1159 have_snd_auth = true;
1147 {
1148 slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n"
1149 "could be an attack, or just corruption or a synchronization error."),
1150 conf->nodename, (const char *)rsi);
1151 break;
1152 }
1153 else
1154 {
1155 rsaresponse h;
1156
1157 rsa_hash (p->id, chg, h);
1158
1159 if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h))
1160 {
1161 prot_minor = p->prot_minor;
1162
1163 delete ictx; ictx = cctx;
1164
1165 iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid
1166
1167 si = rsi;
1168 protocol = rsi.prot;
1169
1170 slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."),
1171 conf->nodename, (const char *)rsi,
1172 is_direct ? "direct" : "forwarded",
1173 p->prot_major, p->prot_minor);
1174
1175 connection_established (); 1160 connection_established (rsi);
1176
1177 if (::conf.script_node_up)
1178 {
1179 run_script_cb *cb = new run_script_cb;
1180 cb->set<connection, &connection::script_node_up> (this);
1181 run_script_queued (cb, _("node-up command execution failed, continuing."));
1182 }
1183
1184 break;
1185 }
1186 else
1187 slog (L_ERR, _("%s(%s): sent and received challenge do not match."),
1188 conf->nodename, (const char *)rsi);
1189 }
1190
1191 delete cctx;
1192 }
1193 } 1161 }
1194 } 1162 }
1195
1196 send_reset (rsi);
1197 break; 1163 break;
1198 1164
1199 case vpn_packet::PT_DATA_COMPRESSED: 1165 case vpn_packet::PT_DATA_COMPRESSED:
1200#if !ENABLE_COMPRESSION 1166#if !ENABLE_COMPRESSION
1201 send_reset (rsi); 1167 send_reset (rsi);
… …
1207 if (ictx && octx) 1173 if (ictx && octx)
1208 { 1174 {
1209 vpndata_packet *p = (vpndata_packet *)pkt; 1175 vpndata_packet *p = (vpndata_packet *)pkt;
1210 1176
1211 if (!p->hmac_chk (ictx)) 1177 if (!p->hmac_chk (ictx))
1178 {
1179 // rekeying often creates temporary hmac auth floods
1180 // we assume they don't take longer than a few seconds normally,
1181 // and suppress messages and resets during that time.
1182 //TODO: should be done per source address
1183 if (!hmac_error)
1184 {
1185 hmac_error = ev_now () + 3;
1186 break;
1187 }
1188 else if (hmac_error >= ev_now ())
1189 break; // silently suppress
1190 else
1191 {
1212 slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" 1192 slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n"
1213 "could be an attack, or just corruption or a synchronization error."), 1193 "could be an attack, or just corruption or a synchronization error."),
1214 conf->nodename, (const char *)rsi); 1194 conf->nodename, (const char *)rsi);
1195 // reset
1196 }
1197 }
1215 else 1198 else
1216 { 1199 {
1217 u32 seqno; 1200 u32 seqno;
1218 tap_packet *d = p->unpack (this, seqno); 1201 tap_packet *d = p->unpack (this, seqno);
1219 int seqclass = iseqno.seqno_classify (seqno); 1202 int seqclass = iseqno.seqno_classify (seqno);
1203
1204 hmac_error = 0;
1220 1205
1221 if (seqclass == 0) // ok 1206 if (seqclass == 0) // ok
1222 { 1207 {
1223 vpn->tap->send (d); 1208 vpn->tap->send (d);
1224 1209
… …
1345} 1330}
1346 1331
1347inline void 1332inline void
1348connection::keepalive_cb (ev::timer &w, int revents) 1333connection::keepalive_cb (ev::timer &w, int revents)
1349{ 1334{
1350 if (ev_now () >= last_activity + ::conf.keepalive + 15) 1335 ev_tstamp when = last_activity + ::conf.keepalive - ev::now ();
1336
1337 if (when >= 0)
1338 w.start (when);
1339 else if (when < -15)
1351 { 1340 {
1352 reset_connection (); 1341 reset_connection ("keepalive overdue");
1353 establish_connection (); 1342 establish_connection ();
1354 } 1343 }
1355 else if (ev_now () < last_activity + ::conf.keepalive)
1356 w.start (last_activity + ::conf.keepalive - ev::now ());
1357 else if (conf->connectmode != conf_node::C_ONDEMAND 1344 else if (conf->connectmode != conf_node::C_ONDEMAND
1358 || THISNODE->connectmode != conf_node::C_ONDEMAND) 1345 || THISNODE->connectmode != conf_node::C_ONDEMAND)
1359 { 1346 {
1347 w.start (3);
1360 send_ping (si); 1348 send_ping (si);
1361 w.start (3);
1362 } 1349 }
1363 else if (ev_now () < last_activity + ::conf.keepalive + 10) 1350 else if (when >= -10)
1364 // hold ondemand connections implicitly a few seconds longer 1351 // hold ondemand connections implicitly a few seconds longer
1365 // should delete octx, though, or something like that ;) 1352 // should delete octx, though, or something like that ;)
1366 w.start (last_activity + ::conf.keepalive + 10 - ev::now ()); 1353 w.start (when + 10);
1367 else 1354 else
1368 reset_connection (); 1355 reset_connection ("keepalive timeout");
1369} 1356}
1370 1357
1371void 1358void
1372connection::send_connect_request (int id) 1359connection::send_connect_request (int id)
1373{ 1360{
… …
1473 1460
1474 // queue a dummy packet to force an initial connection attempt 1461 // queue a dummy packet to force an initial connection attempt
1475 if (connectmode != conf_node::C_ALWAYS && connectmode != conf_node::C_DISABLED) 1462 if (connectmode != conf_node::C_ALWAYS && connectmode != conf_node::C_DISABLED)
1476 vpn_queue.put (new net_packet); 1463 vpn_queue.put (new net_packet);
1477 1464
1478 reset_connection (); 1465 reset_connection ("startup");
1479} 1466}
1480 1467
1481connection::~connection () 1468connection::~connection ()
1482{ 1469{
1483 shutdown (); 1470 shutdown ();

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