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 |
… | |
… | |
43 | #include "conf.h" |
43 | #include "conf.h" |
44 | #include "slog.h" |
44 | #include "slog.h" |
45 | #include "device.h" |
45 | #include "device.h" |
46 | #include "vpn.h" |
46 | #include "vpn.h" |
47 | #include "connection.h" |
47 | #include "connection.h" |
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48 | #include "hkdf.h" |
48 | |
49 | |
49 | #include "netcompat.h" |
50 | #include "netcompat.h" |
50 | |
51 | |
51 | #if !HAVE_RAND_PSEUDO_BYTES |
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52 | # define RAND_pseudo_bytes RAND_bytes |
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53 | #endif |
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54 | |
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55 | #define MAGIC_OLD "vped\xbd\xc6\xdb\x82" // 8 bytes of magic (still used in the protocol) |
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56 | #define MAGIC "gvpe\xbd\xc6\xdb\x82" // 8 bytes of magic (understood but not generated) |
52 | #define MAGIC "gvpe\xbd\xc6\xdb\x82" // 8 bytes of magic |
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53 | #define MAGIC "HUHN\xbd\xc6\xdb\x82" // 8 bytes of magic//D |
57 | |
54 | |
58 | #define ULTRA_FAST 1 |
55 | #define ULTRA_FAST 1 |
59 | #define HLOG 15 |
56 | #define HLOG 15 |
60 | #include "lzf/lzf.h" |
57 | #include "lzf/lzf.h" |
61 | #include "lzf/lzf_c.c" |
58 | #include "lzf/lzf_c.c" |
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… | |
108 | struct crypto_ctx |
105 | struct crypto_ctx |
109 | { |
106 | { |
110 | EVP_CIPHER_CTX cctx; |
107 | EVP_CIPHER_CTX cctx; |
111 | HMAC_CTX hctx; |
108 | HMAC_CTX hctx; |
112 | |
109 | |
113 | crypto_ctx (const rsachallenge &challenge, int enc); |
110 | crypto_ctx (const auth_data &auth1, const auth_data &auth2, const ecdh_key &a, const ecdh_key &b, int enc); |
114 | ~crypto_ctx (); |
111 | ~crypto_ctx (); |
115 | }; |
112 | }; |
116 | |
113 | |
117 | crypto_ctx::crypto_ctx (const rsachallenge &challenge, int enc) |
114 | crypto_ctx::crypto_ctx (const auth_data &auth1, const auth_data &auth2, const ecdh_key &a, const ecdh_key &b, int enc) |
118 | { |
115 | { |
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116 | ecdh_key s; |
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117 | |
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118 | curve25519_combine (a, b, s); |
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119 | |
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120 | { |
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121 | u8 mac_key[MAC_KEYSIZE]; |
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122 | static const unsigned char mac_info[] = "gvpe mac key"; |
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123 | |
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124 | hkdf kdf (auth2.rsa.hkdf_salt, sizeof (auth2.rsa.hkdf_salt), HKDF_XTR_HASH ()); |
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125 | kdf.extract (auth1.rsa.mac_key, sizeof (auth1.rsa.mac_key)); |
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126 | kdf.extract (s, sizeof (s)); |
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127 | kdf.extract_done (HKDF_PRF_HASH ()); |
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128 | kdf.expand (mac_key, sizeof (mac_key), mac_info, sizeof (mac_info)); |
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129 | |
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130 | HMAC_CTX_init (&hctx); |
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131 | require (HMAC_Init_ex (&hctx, mac_key, MAC_KEYSIZE, MAC_DIGEST (), 0)); |
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132 | } |
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133 | |
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134 | { |
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135 | u8 cipher_key[CIPHER_KEYSIZE]; |
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136 | static const unsigned char cipher_info[] = "gvpe cipher key"; |
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137 | |
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138 | hkdf kdf (auth2.rsa.hkdf_salt, sizeof (auth2.rsa.hkdf_salt), HKDF_XTR_HASH ()); |
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139 | kdf.extract (auth1.rsa.cipher_key, sizeof (auth1.rsa.cipher_key)); |
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140 | kdf.extract (s, sizeof (s)); |
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141 | kdf.extract_done (HKDF_PRF_HASH ()); |
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142 | kdf.expand (cipher_key, sizeof (cipher_key), cipher_info, sizeof (cipher_info)); |
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143 | |
119 | EVP_CIPHER_CTX_init (&cctx); |
144 | EVP_CIPHER_CTX_init (&cctx); |
120 | require (EVP_CipherInit_ex (&cctx, CIPHER, 0, &challenge[CHG_CIPHER_KEY], 0, enc)); |
145 | require (EVP_CipherInit_ex (&cctx, CIPHER (), 0, cipher_key, 0, enc)); |
121 | HMAC_CTX_init (&hctx); |
146 | } |
122 | HMAC_Init_ex (&hctx, &challenge[CHG_HMAC_KEY], HMAC_KEYLEN, DIGEST, 0); |
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123 | } |
147 | } |
124 | |
148 | |
125 | crypto_ctx::~crypto_ctx () |
149 | crypto_ctx::~crypto_ctx () |
126 | { |
150 | { |
127 | require (EVP_CIPHER_CTX_cleanup (&cctx)); |
151 | require (EVP_CIPHER_CTX_cleanup (&cctx)); |
128 | HMAC_CTX_cleanup (&hctx); |
152 | HMAC_CTX_cleanup (&hctx); |
129 | } |
153 | } |
130 | |
154 | |
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155 | static inline void |
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156 | auth_encrypt (RSA *key, const auth_data &auth, auth_encr &encr) |
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157 | { |
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158 | if (RSA_public_encrypt (sizeof (auth.rsa), |
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159 | (unsigned char *)&auth.rsa, (unsigned char *)&encr.rsa, |
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160 | key, RSA_PKCS1_OAEP_PADDING) < 0) |
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161 | fatal ("RSA_public_encrypt error"); |
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162 | |
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163 | memcpy (&encr.ecdh, &auth.ecdh, sizeof (encr.ecdh)); |
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164 | } |
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165 | |
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166 | static inline bool |
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167 | auth_decrypt (RSA *key, const auth_encr &encr, auth_data &auth) |
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168 | { |
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169 | u8 rsa_decrypt[RSA_KEYLEN]; |
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170 | |
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171 | if (RSA_private_decrypt (sizeof (encr.rsa), |
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172 | (const unsigned char *)&encr.rsa, (unsigned char *)rsa_decrypt, |
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173 | key, RSA_PKCS1_OAEP_PADDING) != sizeof (auth.rsa)) |
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174 | return 0; |
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175 | |
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176 | memcpy (&auth.rsa, rsa_decrypt, sizeof (auth.rsa)); |
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177 | memcpy (&auth.ecdh, &encr.ecdh, sizeof (auth.ecdh)); |
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178 | |
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179 | return 1; |
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180 | } |
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181 | |
131 | static void |
182 | static void |
132 | rsa_hash (const rsaid &id, const rsachallenge &chg, rsaresponse &h) |
183 | auth_hash (const auth_data &auth, auth_mac &mac) |
133 | { |
184 | { |
134 | EVP_MD_CTX ctx; |
185 | HMAC_CTX ctx; |
135 | |
186 | |
136 | EVP_MD_CTX_init (&ctx); |
187 | HMAC_CTX_init (&ctx); |
137 | require (EVP_DigestInit (&ctx, RSA_HASH)); |
188 | require (HMAC_Init_ex (&ctx, auth.rsa.auth_key, sizeof (auth.rsa.auth_key), AUTH_DIGEST (), 0)); |
138 | require (EVP_DigestUpdate(&ctx, &chg, sizeof chg)); |
189 | require (HMAC_Update (&ctx, (const unsigned char *)&auth, sizeof auth)); |
139 | require (EVP_DigestUpdate(&ctx, &id, sizeof id)); |
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140 | require (EVP_DigestFinal (&ctx, (unsigned char *)&h, 0)); |
190 | require (HMAC_Final (&ctx, (unsigned char *)&mac, 0)); |
141 | EVP_MD_CTX_cleanup (&ctx); |
191 | HMAC_CTX_cleanup (&ctx); |
142 | } |
192 | } |
143 | |
193 | |
144 | struct rsa_entry |
194 | void |
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195 | connection::generate_auth_data () |
145 | { |
196 | { |
146 | tstamp expire; |
197 | if (auth_expire < ev_now ()) |
147 | rsaid id; |
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148 | rsachallenge chg; |
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149 | }; |
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150 | |
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151 | struct rsa_cache : list<rsa_entry> |
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152 | { |
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153 | inline void cleaner_cb (ev::timer &w, int revents); ev::timer cleaner; |
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154 | |
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155 | bool find (const rsaid &id, rsachallenge &chg) |
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156 | { |
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157 | for (iterator i = begin (); i != end (); ++i) |
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158 | { |
198 | { |
159 | if (!memcmp (&id, &i->id, sizeof id) && i->expire > ev_now ()) |
199 | // request data |
160 | { |
200 | rand_fill (snd_auth.rsa); |
161 | memcpy (&chg, &i->chg, sizeof chg); |
201 | curve25519_generate (snd_ecdh_a, snd_auth.ecdh); |
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202 | auth_hash (snd_auth, snd_auth_mac); |
162 | |
203 | |
163 | erase (i); |
204 | // eventual response data |
164 | return true; |
205 | curve25519_generate (rcv_ecdh_a, rcv_ecdh_b); |
165 | } |
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166 | } |
206 | } |
167 | |
207 | |
168 | if (!cleaner.is_active ()) |
208 | // every use prolongs the expiry |
169 | cleaner.again (); |
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170 | |
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171 | return false; |
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172 | } |
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173 | |
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174 | void gen (rsaid &id, rsachallenge &chg) |
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175 | { |
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176 | rsa_entry e; |
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177 | |
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178 | RAND_bytes ((unsigned char *)&id, sizeof id); |
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179 | RAND_bytes ((unsigned char *)&chg, sizeof chg); |
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180 | |
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181 | e.expire = ev_now () + RSA_TTL; |
209 | auth_expire = ev_now () + AUTH_TTL; |
182 | e.id = id; |
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183 | memcpy (&e.chg, &chg, sizeof chg); |
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184 | |
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185 | push_back (e); |
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186 | |
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187 | if (!cleaner.is_active ()) |
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188 | cleaner.again (); |
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189 | } |
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190 | |
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191 | rsa_cache () |
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192 | { |
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193 | cleaner.set<rsa_cache, &rsa_cache::cleaner_cb> (this); |
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194 | cleaner.set (RSA_TTL, RSA_TTL); |
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195 | } |
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196 | |
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197 | } rsa_cache; |
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198 | |
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199 | void |
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200 | rsa_cache::cleaner_cb (ev::timer &w, int revents) |
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201 | { |
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202 | if (empty ()) |
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203 | w.stop (); |
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204 | else |
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205 | { |
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206 | for (iterator i = begin (); i != end (); ) |
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207 | if (i->expire <= ev_now ()) |
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208 | i = erase (i); |
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209 | else |
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210 | ++i; |
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211 | } |
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212 | } |
210 | } |
213 | |
211 | |
214 | ////////////////////////////////////////////////////////////////////////////// |
212 | ////////////////////////////////////////////////////////////////////////////// |
215 | |
213 | |
216 | pkt_queue::pkt_queue (double max_ttl, int max_queue) |
214 | pkt_queue::pkt_queue (double max_ttl, int max_queue) |
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374 | { |
372 | { |
375 | unsigned int xlen; |
373 | unsigned int xlen; |
376 | |
374 | |
377 | HMAC_CTX *hctx = &ctx->hctx; |
375 | HMAC_CTX *hctx = &ctx->hctx; |
378 | |
376 | |
379 | HMAC_Init_ex (hctx, 0, 0, 0, 0); |
377 | require (HMAC_Init_ex (hctx, 0, 0, 0, 0)); |
380 | HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet), |
378 | require (HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet), |
381 | len - sizeof (hmac_packet)); |
379 | len - sizeof (hmac_packet))); |
382 | HMAC_Final (hctx, (unsigned char *) &hmac_digest, &xlen); |
380 | require (HMAC_Final (hctx, (unsigned char *) &hmac_digest, &xlen)); |
383 | } |
381 | } |
384 | |
382 | |
385 | void |
383 | void |
386 | hmac_packet::hmac_set (crypto_ctx *ctx) |
384 | hmac_packet::hmac_set (crypto_ctx *ctx) |
387 | { |
385 | { |
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451 | d[1] = cl; |
449 | d[1] = cl; |
452 | } |
450 | } |
453 | } |
451 | } |
454 | #endif |
452 | #endif |
455 | |
453 | |
456 | require (EVP_EncryptInit_ex (cctx, 0, 0, 0, 0)); |
454 | require (EVP_CipherInit_ex (cctx, 0, 0, 0, 0, 1)); |
457 | |
455 | |
458 | struct { |
456 | struct { |
459 | #if RAND_SIZE |
457 | #if RAND_SIZE |
460 | u8 rnd[RAND_SIZE]; |
458 | u8 rnd[RAND_SIZE]; |
461 | #endif |
459 | #endif |
462 | u32 seqno; |
460 | u32 seqno; |
463 | } datahdr; |
461 | } datahdr; |
464 | |
462 | |
465 | datahdr.seqno = ntohl (seqno); |
463 | datahdr.seqno = ntohl (seqno); |
466 | #if RAND_SIZE |
464 | #if RAND_SIZE |
467 | RAND_pseudo_bytes ((unsigned char *) datahdr.rnd, RAND_SIZE); |
465 | // NB: a constant (per session) random prefix |
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466 | // is likely enough, but we don't take any chances. |
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467 | conn->oiv.get (datahdr.rnd, RAND_SIZE); |
468 | #endif |
468 | #endif |
469 | |
469 | |
470 | require (EVP_EncryptUpdate (cctx, |
470 | require (EVP_EncryptUpdate (cctx, |
471 | (unsigned char *) data + outl, &outl2, |
471 | (unsigned char *) data + outl, &outl2, |
472 | (unsigned char *) &datahdr, DATAHDR)); |
472 | (unsigned char *) &datahdr, DATAHDR)); |
… | |
… | |
494 | int outl = 0, outl2; |
494 | int outl = 0, outl2; |
495 | tap_packet *p = new tap_packet; |
495 | tap_packet *p = new tap_packet; |
496 | u8 *d; |
496 | u8 *d; |
497 | u32 l = len - data_hdr_size (); |
497 | u32 l = len - data_hdr_size (); |
498 | |
498 | |
499 | require (EVP_DecryptInit_ex (cctx, 0, 0, 0, 0)); |
499 | require (EVP_CipherInit_ex (cctx, 0, 0, 0, 0, 0)); |
500 | |
500 | |
501 | #if ENABLE_COMPRESSION |
501 | #if ENABLE_COMPRESSION |
502 | u8 cdata[MAX_MTU]; |
502 | u8 cdata[MAX_MTU]; |
503 | |
503 | |
504 | if (type == PT_DATA_COMPRESSED) |
504 | if (type == PT_DATA_COMPRESSED) |
505 | d = cdata; |
505 | d = cdata; |
506 | else |
506 | else |
507 | #endif |
507 | #endif |
508 | d = &(*p)[6 + 6 - DATAHDR]; |
508 | d = &(*p)[6 + 6] - DATAHDR; |
509 | |
509 | |
510 | /* this overwrites part of the src mac, but we fix that later */ |
510 | // we play do evil games with the struct layout atm. |
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511 | // pending better solutions, we at least do some verification. |
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512 | // this is fine, as we left ISO territory long ago. |
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513 | require (DATAHDR <= 16); |
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514 | require ((u8 *)(&p->len + 1) == &(*p)[0]); |
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515 | |
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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 | |
… | |
… | |
546 | } |
552 | } |
547 | }; |
553 | }; |
548 | |
554 | |
549 | struct config_packet : vpn_packet |
555 | struct config_packet : vpn_packet |
550 | { |
556 | { |
551 | // actually, hmaclen cannot be checked because the hmac |
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552 | // field comes before this data, so peers with other |
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553 | // hmacs simply will not work. |
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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; |
560 | |
563 | |
561 | static u8 get_features () |
564 | static u8 get_features () |
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… | |
578 | config_packet::setup (ptype type, int dst) |
581 | config_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; |
585 | randsize = RAND_SIZE; |
583 | hmaclen = HMACLENGTH; |
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584 | flags = 0; |
586 | flags = 0; |
585 | challengelen = sizeof (rsachallenge); |
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586 | features = get_features (); |
587 | features = get_features (); |
587 | |
588 | |
588 | cipher_nid = htonl (EVP_CIPHER_nid (CIPHER)); |
589 | cipher_nid = htonl (EVP_CIPHER_nid (CIPHER ())); |
589 | digest_nid = htonl (EVP_MD_type (RSA_HASH)); |
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590 | hmac_nid = htonl (EVP_MD_type (DIGEST)); |
590 | mac_nid = htonl (EVP_MD_type (MAC_DIGEST ())); |
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591 | auth_nid = htonl (EVP_MD_type (AUTH_DIGEST ())); |
591 | |
592 | |
592 | len = sizeof (*this) - sizeof (net_packet); |
593 | len = sizeof (*this) - sizeof (net_packet); |
593 | set_hdr (type, dst); |
594 | set_hdr (type, dst); |
594 | } |
595 | } |
595 | |
596 | |
… | |
… | |
598 | { |
599 | { |
599 | if (prot_major != PROTOCOL_MAJOR) |
600 | if (prot_major != PROTOCOL_MAJOR) |
600 | slog (L_WARN, _("major version mismatch (remote %d <=> local %d)"), prot_major, PROTOCOL_MAJOR); |
601 | slog (L_WARN, _("major version mismatch (remote %d <=> local %d)"), prot_major, PROTOCOL_MAJOR); |
601 | else if (randsize != RAND_SIZE) |
602 | else if (randsize != RAND_SIZE) |
602 | slog (L_WARN, _("rand size mismatch (remote %d <=> local %d)"), randsize, RAND_SIZE); |
603 | slog (L_WARN, _("rand size mismatch (remote %d <=> local %d)"), randsize, RAND_SIZE); |
603 | else if (hmaclen != HMACLENGTH) |
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604 | slog (L_WARN, _("hmac length mismatch (remote %d <=> local %d)"), hmaclen, HMACLENGTH); |
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605 | else if (challengelen != sizeof (rsachallenge)) |
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606 | slog (L_WARN, _("challenge length mismatch (remote %d <=> local %d)"), challengelen, sizeof (rsachallenge)); |
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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, _("cipher algo mismatch (remote %x <=> local %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER ())); |
609 | else if (digest_nid != htonl (EVP_MD_type (RSA_HASH))) |
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610 | slog (L_WARN, _("digest mismatch (remote %x <=> local %x)"), ntohl (digest_nid), EVP_MD_type (RSA_HASH)); |
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611 | else if (hmac_nid != htonl (EVP_MD_type (DIGEST))) |
606 | 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)); |
607 | slog (L_WARN, _("mac algo mismatch (remote %x <=> local %x)"), ntohl (mac_nid), EVP_MD_type (MAC_DIGEST ())); |
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608 | else if (auth_nid != htonl (EVP_MD_type (AUTH_DIGEST ()))) |
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609 | slog (L_WARN, _("auth algo mismatch (remote %x <=> local %x)"), ntohl (auth_nid), EVP_MD_type (AUTH_DIGEST ())); |
613 | else |
610 | else |
614 | return true; |
611 | return true; |
615 | |
612 | |
616 | return false; |
613 | return false; |
617 | } |
614 | } |
618 | |
615 | |
619 | struct auth_req_packet : config_packet |
616 | struct auth_req_packet : config_packet // UNPROTECTED |
620 | { |
617 | { |
621 | char magic[8]; |
618 | char magic[8]; |
622 | u8 initiate; // false if this is just an automatic reply |
619 | u8 initiate; // false if this is just an automatic reply |
623 | u8 protocols; // supported protocols (will be patched on forward) |
620 | u8 protocols; // supported protocols (will be patched on forward) |
624 | u8 pad2, pad3; |
621 | u8 pad2, pad3; |
625 | rsaid id; |
622 | auth_encr encr; |
626 | rsaencrdata encr; |
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627 | |
623 | |
628 | auth_req_packet (int dst, bool initiate_, u8 protocols_) |
624 | auth_req_packet (int dst, bool initiate_, u8 protocols_) |
629 | { |
625 | { |
630 | config_packet::setup (PT_AUTH_REQ, dst); |
626 | config_packet::setup (PT_AUTH_REQ, dst); |
631 | strncpy (magic, MAGIC_OLD, 8); |
627 | memcpy (magic, MAGIC, 8); |
632 | initiate = !!initiate_; |
628 | initiate = !!initiate_; |
633 | protocols = protocols_; |
629 | protocols = protocols_; |
634 | |
630 | |
635 | len = sizeof (*this) - sizeof (net_packet); |
631 | len = sizeof (*this) - sizeof (net_packet); |
636 | } |
632 | } |
637 | }; |
633 | }; |
638 | |
634 | |
639 | struct auth_res_packet : config_packet |
635 | struct auth_res_packet : config_packet // UNPROTECTED |
640 | { |
636 | { |
641 | rsaid id; |
|
|
642 | u8 pad1, pad2, pad3; |
|
|
643 | u8 response_len; // encrypted length |
|
|
644 | rsaresponse response; |
637 | auth_response response; |
645 | |
638 | |
646 | auth_res_packet (int dst) |
639 | auth_res_packet (int dst) |
647 | { |
640 | { |
648 | config_packet::setup (PT_AUTH_RES, dst); |
641 | config_packet::setup (PT_AUTH_RES, dst); |
649 | |
642 | |
… | |
… | |
683 | }; |
676 | }; |
684 | |
677 | |
685 | ///////////////////////////////////////////////////////////////////////////// |
678 | ///////////////////////////////////////////////////////////////////////////// |
686 | |
679 | |
687 | void |
680 | void |
688 | connection::connection_established () |
681 | connection::connection_established (const sockinfo &rsi) |
689 | { |
682 | { |
690 | slog (L_NOISE, _("%s: possible connection establish (ictx %d, octx %d)"), conf->nodename, !!ictx, !!octx); |
683 | if (!have_snd_auth || !have_rcv_auth) |
|
|
684 | return; |
691 | |
685 | |
|
|
686 | si = rsi; |
|
|
687 | protocol = rsi.prot; |
|
|
688 | |
|
|
689 | slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."), |
|
|
690 | conf->nodename, (const char *)rsi, |
|
|
691 | is_direct ? "direct" : "forwarded", |
|
|
692 | PROTOCOL_MAJOR, prot_minor); |
|
|
693 | |
|
|
694 | if (::conf.script_node_up) |
|
|
695 | { |
|
|
696 | run_script_cb *cb = new run_script_cb; |
|
|
697 | cb->set<connection, &connection::script_node_up> (this); |
|
|
698 | run_script_queued (cb, _("node-up command execution failed, continuing.")); |
|
|
699 | } |
|
|
700 | |
|
|
701 | delete ictx; ictx = new crypto_ctx (rcv_auth, snd_auth, rcv_ecdh_a, rcv_auth.ecdh, 0); |
|
|
702 | iseqno.reset (ntohl (rcv_auth.rsa.seqno) & 0x7fffffff); |
|
|
703 | |
|
|
704 | delete octx; octx = new crypto_ctx (snd_auth, rcv_auth, snd_ecdh_a, snd_ecdh_b , 1); |
|
|
705 | oseqno = ntohl (snd_auth.rsa.seqno) & 0x7fffffff; |
|
|
706 | |
|
|
707 | oiv.reset (); |
|
|
708 | |
|
|
709 | // make sure rekeying timeouts are slightly asymmetric |
|
|
710 | ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0); |
|
|
711 | rekey.start (rekey_interval, rekey_interval); |
|
|
712 | |
|
|
713 | keepalive.start (::conf.keepalive); |
|
|
714 | |
|
|
715 | // send queued packets |
692 | if (ictx && octx) |
716 | if (ictx && octx) |
693 | { |
717 | { |
694 | // make sure rekeying timeouts are slightly asymmetric |
718 | while (tap_packet *p = (tap_packet *)data_queue.get ()) |
695 | ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0); |
|
|
696 | rekey.start (rekey_interval, rekey_interval); |
|
|
697 | keepalive.start (::conf.keepalive); |
|
|
698 | |
|
|
699 | // send queued packets |
|
|
700 | if (ictx && octx) |
|
|
701 | { |
719 | { |
702 | while (tap_packet *p = (tap_packet *)data_queue.get ()) |
|
|
703 | { |
|
|
704 | if (p->len) send_data_packet (p); |
720 | if (p->len) send_data_packet (p); |
705 | delete p; |
721 | delete p; |
706 | } |
|
|
707 | |
|
|
708 | while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) |
|
|
709 | { |
|
|
710 | if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY); |
|
|
711 | delete p; |
|
|
712 | } |
|
|
713 | } |
722 | } |
714 | |
723 | |
|
|
724 | while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) |
|
|
725 | { |
|
|
726 | if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY); |
|
|
727 | delete p; |
|
|
728 | } |
|
|
729 | } |
|
|
730 | |
715 | vpn->connection_established (this); |
731 | 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 | } |
732 | } |
725 | |
733 | |
726 | void |
734 | void |
727 | connection::reset_si () |
735 | connection::reset_si () |
728 | { |
736 | { |
… | |
… | |
774 | ping_packet *pkt = new ping_packet; |
782 | ping_packet *pkt = new ping_packet; |
775 | |
783 | |
776 | pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); |
784 | pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); |
777 | |
785 | |
778 | slog (L_TRACE, "%s << %s [%s]", conf->nodename, pong ? "PT_PONG" : "PT_PING", (const char *)si); |
786 | 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); |
787 | send_vpn_packet (pkt, si, IPTOS_LOWDELAY); |
781 | |
788 | |
782 | delete pkt; |
789 | delete pkt; |
783 | } |
790 | } |
784 | |
791 | |
… | |
… | |
799 | void |
806 | void |
800 | connection::send_auth_request (const sockinfo &si, bool initiate) |
807 | connection::send_auth_request (const sockinfo &si, bool initiate) |
801 | { |
808 | { |
802 | auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols); |
809 | auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols); |
803 | |
810 | |
804 | rsachallenge chg; |
811 | generate_auth_data (); |
805 | rsa_cache.gen (pkt->id, chg); |
|
|
806 | rsa_encrypt (conf->rsa_key, chg, pkt->encr); |
812 | auth_encrypt (conf->rsa_key, snd_auth, pkt->encr); |
807 | |
813 | |
808 | slog (L_TRACE, "%s << PT_AUTH_REQ [%s]", conf->nodename, (const char *)si); |
814 | 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 |
815 | send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly |
811 | |
816 | |
812 | delete pkt; |
817 | delete pkt; |
813 | } |
818 | } |
814 | |
819 | |
815 | void |
820 | void |
816 | connection::send_auth_response (const sockinfo &si, const rsaid &id, const rsachallenge &chg) |
821 | connection::send_auth_response (const sockinfo &si) |
817 | { |
822 | { |
818 | auth_res_packet *pkt = new auth_res_packet (conf->id); |
823 | auth_res_packet *pkt = new auth_res_packet (conf->id); |
819 | |
824 | |
820 | pkt->id = id; |
825 | auth_hash (rcv_auth, pkt->response.mac); |
821 | |
826 | memcpy (pkt->response.ecdh, rcv_ecdh_b, sizeof (rcv_ecdh_b)); |
822 | rsa_hash (id, chg, pkt->response); |
|
|
823 | |
|
|
824 | pkt->hmac_set (octx); |
|
|
825 | |
827 | |
826 | slog (L_TRACE, "%s << PT_AUTH_RES [%s]", conf->nodename, (const char *)si); |
828 | 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 |
829 | send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly |
829 | |
830 | |
830 | delete pkt; |
831 | delete pkt; |
831 | } |
832 | } |
832 | |
833 | |
… | |
… | |
924 | } |
925 | } |
925 | } |
926 | } |
926 | |
927 | |
927 | delete ictx; ictx = 0; |
928 | delete ictx; ictx = 0; |
928 | delete octx; octx = 0; |
929 | delete octx; octx = 0; |
929 | #if ENABLE_DNS |
|
|
930 | dnsv4_reset_connection (); |
|
|
931 | #endif |
|
|
932 | |
930 | |
933 | si.host = 0; |
931 | si.host = 0; |
|
|
932 | |
|
|
933 | have_snd_auth = false; |
|
|
934 | have_rcv_auth = false; |
|
|
935 | auth_expire = 0.; |
934 | |
936 | |
935 | last_activity = 0.; |
937 | last_activity = 0.; |
936 | //last_si_change = 0.; |
938 | //last_si_change = 0.; |
937 | retry_cnt = 0; |
939 | retry_cnt = 0; |
938 | |
940 | |
… | |
… | |
1074 | |
1076 | |
1075 | slog (L_TRACE, "%s >> PT_AUTH_REQ(%s,p%02x,f%02x)", |
1077 | slog (L_TRACE, "%s >> PT_AUTH_REQ(%s,p%02x,f%02x)", |
1076 | conf->nodename, p->initiate ? "initiate" : "reply", |
1078 | conf->nodename, p->initiate ? "initiate" : "reply", |
1077 | p->protocols, p->features); |
1079 | p->protocols, p->features); |
1078 | |
1080 | |
1079 | if (p->chk_config () |
1081 | if (p->chk_config () && !memcmp (p->magic, MAGIC, 8)) |
1080 | && (!memcmp (p->magic, MAGIC_OLD, 8) || !memcmp (p->magic, MAGIC, 8))) |
|
|
1081 | { |
1082 | { |
1082 | if (p->prot_minor != PROTOCOL_MINOR) |
1083 | if (p->prot_minor != PROTOCOL_MINOR) |
1083 | slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
1084 | slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
1084 | conf->nodename, (const char *)rsi, |
1085 | conf->nodename, (const char *)rsi, |
1085 | PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
1086 | PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
1086 | |
1087 | |
1087 | if (p->initiate) |
1088 | if (p->initiate) |
1088 | send_auth_request (rsi, false); |
1089 | send_auth_request (rsi, false); |
1089 | |
1090 | |
1090 | rsachallenge k; |
1091 | auth_data auth; |
1091 | |
1092 | |
1092 | if (!rsa_decrypt (::conf.rsa_key, p->encr, k)) |
1093 | if (!auth_decrypt (::conf.rsa_key, p->encr, auth)) |
1093 | { |
1094 | { |
1094 | slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), |
1095 | slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), |
1095 | conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); |
1096 | conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); |
1096 | break; |
|
|
1097 | } |
1097 | } |
1098 | else |
1098 | else |
1099 | { |
1099 | { |
1100 | delete octx; |
1100 | bool chg = !have_rcv_auth || memcmp (&rcv_auth, &auth, sizeof auth); |
1101 | |
1101 | |
1102 | octx = new crypto_ctx (k, 1); |
1102 | rcv_auth = auth; |
1103 | oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; |
1103 | have_rcv_auth = true; |
1104 | |
1104 | |
|
|
1105 | send_auth_response (rsi); |
|
|
1106 | |
|
|
1107 | if (chg) |
|
|
1108 | { |
1105 | conf->protocols = p->protocols; |
1109 | conf->protocols = p->protocols; |
1106 | features = p->features & config_packet::get_features (); |
1110 | features = p->features & config_packet::get_features (); |
1107 | |
1111 | |
1108 | send_auth_response (rsi, p->id, k); |
|
|
1109 | |
|
|
1110 | connection_established (); |
1112 | connection_established (rsi); |
1111 | |
|
|
1112 | break; |
1113 | } |
1113 | } |
1114 | } |
|
|
1115 | |
|
|
1116 | break; |
1114 | } |
1117 | } |
1115 | else |
1118 | else |
1116 | slog (L_WARN, _("%s(%s): protocol mismatch."), |
1119 | slog (L_WARN, _("%s(%s): protocol mismatch."), |
1117 | conf->nodename, (const char *)rsi); |
1120 | conf->nodename, (const char *)rsi); |
1118 | |
1121 | |
… | |
… | |
1127 | |
1130 | |
1128 | slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename); |
1131 | slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename); |
1129 | |
1132 | |
1130 | if (p->chk_config ()) |
1133 | if (p->chk_config ()) |
1131 | { |
1134 | { |
1132 | if (p->prot_minor != PROTOCOL_MINOR) |
1135 | if (memcmp (&p->response.mac, snd_auth_mac, sizeof (snd_auth_mac))) |
1133 | slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
|
|
1134 | conf->nodename, (const char *)rsi, |
|
|
1135 | PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
|
|
1136 | |
|
|
1137 | rsachallenge chg; |
|
|
1138 | |
|
|
1139 | if (!rsa_cache.find (p->id, chg)) |
|
|
1140 | { |
1136 | { |
1141 | slog (L_ERR, _("%s(%s): unrequested auth response, ignoring."), |
1137 | slog (L_ERR, _("%s(%s): unrequested or outdated auth response, ignoring."), |
1142 | conf->nodename, (const char *)rsi); |
1138 | conf->nodename, (const char *)rsi); |
1143 | break; |
|
|
1144 | } |
1139 | } |
1145 | else |
1140 | else if (!have_snd_auth) |
1146 | { |
1141 | { |
1147 | crypto_ctx *cctx = new crypto_ctx (chg, 0); |
1142 | if (p->prot_minor != PROTOCOL_MINOR) |
1148 | |
1143 | slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), |
1149 | if (!p->hmac_chk (cctx)) |
|
|
1150 | { |
|
|
1151 | slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n" |
|
|
1152 | "could be an attack, or just corruption or a synchronization error."), |
|
|
1153 | conf->nodename, (const char *)rsi); |
1144 | conf->nodename, (const char *)rsi, |
1154 | break; |
1145 | PROTOCOL_MINOR, conf->nodename, p->prot_minor); |
1155 | } |
|
|
1156 | else |
|
|
1157 | { |
|
|
1158 | rsaresponse h; |
|
|
1159 | |
1146 | |
1160 | rsa_hash (p->id, chg, h); |
|
|
1161 | |
|
|
1162 | if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h)) |
|
|
1163 | { |
|
|
1164 | prot_minor = p->prot_minor; |
1147 | prot_minor = p->prot_minor; |
|
|
1148 | memcpy (snd_ecdh_b, p->response.ecdh, sizeof (snd_ecdh_b)); |
1165 | |
1149 | |
1166 | delete ictx; ictx = cctx; |
1150 | have_snd_auth = true; |
1167 | |
|
|
1168 | iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid |
|
|
1169 | |
|
|
1170 | si = rsi; |
|
|
1171 | protocol = rsi.prot; |
|
|
1172 | |
|
|
1173 | slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."), |
|
|
1174 | conf->nodename, (const char *)rsi, |
|
|
1175 | is_direct ? "direct" : "forwarded", |
|
|
1176 | p->prot_major, p->prot_minor); |
|
|
1177 | |
|
|
1178 | connection_established (); |
1151 | connection_established (rsi); |
1179 | |
|
|
1180 | if (::conf.script_node_up) |
|
|
1181 | { |
|
|
1182 | run_script_cb *cb = new run_script_cb; |
|
|
1183 | cb->set<connection, &connection::script_node_up> (this); |
|
|
1184 | run_script_queued (cb, _("node-up command execution failed, continuing.")); |
|
|
1185 | } |
|
|
1186 | |
|
|
1187 | break; |
|
|
1188 | } |
|
|
1189 | else |
|
|
1190 | slog (L_ERR, _("%s(%s): sent and received challenge do not match."), |
|
|
1191 | conf->nodename, (const char *)rsi); |
|
|
1192 | } |
|
|
1193 | |
|
|
1194 | delete cctx; |
|
|
1195 | } |
1152 | } |
|
|
1153 | |
|
|
1154 | break; |
1196 | } |
1155 | } |
1197 | } |
1156 | } |
1198 | |
1157 | |
1199 | send_reset (rsi); |
1158 | send_reset (rsi); |
1200 | break; |
1159 | break; |
… | |
… | |
1313 | |
1272 | |
1314 | c->conf->protocols = p->protocols; |
1273 | c->conf->protocols = p->protocols; |
1315 | protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf)); |
1274 | protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf)); |
1316 | p->si.upgrade_protocol (protocol, c->conf); |
1275 | p->si.upgrade_protocol (protocol, c->conf); |
1317 | |
1276 | |
1318 | slog (L_TRACE, "%s >> PT_CONNECT_INFO(%s,%s,p%02x) [%d]", |
1277 | slog (L_TRACE, "%s >> PT_CONNECT_INFO(%s,%s,protocols=%02x,protocol=%02x,upgradable=%02x) [%d]", |
1319 | conf->nodename, |
1278 | conf->nodename, |
1320 | vpn->conns[p->id - 1]->conf->nodename, |
1279 | vpn->conns[p->id - 1]->conf->nodename, |
1321 | (const char *)p->si, |
1280 | (const char *)p->si, |
1322 | p->protocols, |
1281 | p->protocols, |
|
|
1282 | protocol, |
|
|
1283 | p->si.supported_protocols (c->conf), |
1323 | !c->ictx && !c->octx); |
1284 | !c->ictx && !c->octx); |
1324 | |
1285 | |
1325 | const sockinfo &dsi = forward_si (p->si); |
1286 | const sockinfo &dsi = forward_si (p->si); |
1326 | |
1287 | |
1327 | if (dsi.valid ()) |
1288 | if (dsi.valid ()) |
1328 | c->send_auth_request (dsi, true); |
1289 | c->send_auth_request (dsi, true); |
|
|
1290 | else |
|
|
1291 | slog (L_INFO, "connect info for %s received (%s), but still unable to contact.", |
|
|
1292 | vpn->conns[p->id - 1]->conf->nodename, |
|
|
1293 | (const char *)p->si); |
1329 | } |
1294 | } |
1330 | else |
1295 | else |
1331 | slog (L_WARN, |
1296 | slog (L_WARN, |
1332 | _("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1297 | _("received authenticated connection request from unknown node #%d, config file mismatch?"), |
1333 | p->id); |
1298 | p->id); |
… | |
… | |
1342 | } |
1307 | } |
1343 | |
1308 | |
1344 | inline void |
1309 | inline void |
1345 | connection::keepalive_cb (ev::timer &w, int revents) |
1310 | connection::keepalive_cb (ev::timer &w, int revents) |
1346 | { |
1311 | { |
1347 | if (ev_now () >= last_activity + ::conf.keepalive + 15) |
1312 | ev_tstamp when = last_activity + ::conf.keepalive - ev::now (); |
|
|
1313 | |
|
|
1314 | if (when >= 0) |
|
|
1315 | w.start (when); |
|
|
1316 | else if (when < -15) |
1348 | { |
1317 | { |
1349 | reset_connection (); |
1318 | reset_connection (); |
1350 | establish_connection (); |
1319 | establish_connection (); |
1351 | } |
1320 | } |
1352 | else if (ev_now () < last_activity + ::conf.keepalive) |
|
|
1353 | w.start (last_activity + ::conf.keepalive - ev::now ()); |
|
|
1354 | else if (conf->connectmode != conf_node::C_ONDEMAND |
1321 | else if (conf->connectmode != conf_node::C_ONDEMAND |
1355 | || THISNODE->connectmode != conf_node::C_ONDEMAND) |
1322 | || THISNODE->connectmode != conf_node::C_ONDEMAND) |
1356 | { |
1323 | { |
|
|
1324 | w.start (3); |
1357 | send_ping (si); |
1325 | send_ping (si); |
1358 | w.start (3); |
|
|
1359 | } |
1326 | } |
1360 | else if (ev_now () < last_activity + ::conf.keepalive + 10) |
1327 | else if (when >= -10) |
1361 | // hold ondemand connections implicitly a few seconds longer |
1328 | // hold ondemand connections implicitly a few seconds longer |
1362 | // should delete octx, though, or something like that ;) |
1329 | // should delete octx, though, or something like that ;) |
1363 | w.start (last_activity + ::conf.keepalive + 10 - ev::now ()); |
1330 | w.start (when + 10); |
1364 | else |
1331 | else |
1365 | reset_connection (); |
1332 | reset_connection (); |
1366 | } |
1333 | } |
1367 | |
1334 | |
1368 | void |
1335 | void |