X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fprotocol_auth.c;h=16abc055c2057505a06b38ca1bde634ed199a35f;hb=0289162552cd85375605044c696e2a3294e7aa9a;hp=68dd071712a4d5f1021fb98a0558036b2d028641;hpb=f6e87ab476a0faf8b124ecaaa27f967d825e6457;p=tinc diff --git a/src/protocol_auth.c b/src/protocol_auth.c index 68dd0717..16abc055 100644 --- a/src/protocol_auth.c +++ b/src/protocol_auth.c @@ -1,7 +1,7 @@ /* protocol_auth.c -- handle the meta-protocol, authentication Copyright (C) 1999-2005 Ivo Timmermans, - 2000-2017 Guus Sliepen + 2000-2022 Guus Sliepen This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -25,8 +25,6 @@ #include "control.h" #include "control_common.h" #include "cipher.h" -#include "crypto.h" -#include "device.h" #include "digest.h" #include "ecdsa.h" #include "edge.h" @@ -37,15 +35,19 @@ #include "net.h" #include "netutl.h" #include "node.h" -#include "prf.h" #include "protocol.h" #include "rsa.h" #include "script.h" #include "sptps.h" #include "utils.h" #include "xalloc.h" +#include "random.h" #include "ed25519/sha512.h" +#include "keys.h" + +/* If nonzero, use null ciphers and skip all key exchanges. */ +bool bypass_security = false; int invitation_lifetime; ecdsa_t *invitation_key = NULL; @@ -69,7 +71,8 @@ static bool send_proxyrequest(connection_t *c) { return false; } - char s4req[9 + (proxyuser ? strlen(proxyuser) : 0)]; + const size_t s4reqlen = 9 + (proxyuser ? strlen(proxyuser) : 0); + uint8_t *s4req = alloca(s4reqlen); s4req[0] = 4; s4req[1] = 1; memcpy(s4req + 2, &c->address.in.sin_port, 2); @@ -79,21 +82,22 @@ static bool send_proxyrequest(connection_t *c) { memcpy(s4req + 8, proxyuser, strlen(proxyuser)); } - s4req[sizeof(s4req) - 1] = 0; + s4req[s4reqlen - 1] = 0; c->tcplen = 8; - return send_meta(c, s4req, sizeof(s4req)); + return send_meta(c, s4req, s4reqlen); } case PROXY_SOCKS5: { - int len = 3 + 6 + (c->address.sa.sa_family == AF_INET ? 4 : 16); + size_t len = 3 + 6 + (c->address.sa.sa_family == AF_INET ? 4 : 16); c->tcplen = 2; if(proxypass) { len += 3 + strlen(proxyuser) + strlen(proxypass); } - char s5req[len]; - int i = 0; + uint8_t *s5req = alloca(len); + + size_t i = 0; s5req[i++] = 5; s5req[i++] = 1; @@ -138,7 +142,7 @@ static bool send_proxyrequest(connection_t *c) { abort(); } - return send_meta(c, s5req, sizeof(s5req)); + return send_meta(c, s5req, len); } case PROXY_SOCKS4A: @@ -160,7 +164,7 @@ bool send_id(connection_t *c) { int minor = 0; if(experimental) { - if(c->outgoing && !read_ecdsa_public_key(c)) { + if(c->outgoing && !read_ecdsa_public_key(&c->ecdsa, &c->config_tree, c->name)) { minor = 1; } else { minor = myself->connection->protocol_minor; @@ -176,6 +180,8 @@ bool send_id(connection_t *c) { } static bool finalize_invitation(connection_t *c, const char *data, uint16_t len) { + (void)len; + if(strchr(data, '\n')) { logger(DEBUG_ALWAYS, LOG_ERR, "Received invalid key from invited node %s (%s)!\n", c->name, c->hostname); return false; @@ -200,7 +206,7 @@ static bool finalize_invitation(connection_t *c, const char *data, uint16_t len) fprintf(f, "Ed25519PublicKey = %s\n", data); fclose(f); - logger(DEBUG_CONNECTIONS, LOG_INFO, "Key succesfully received from %s (%s)", c->name, c->hostname); + logger(DEBUG_CONNECTIONS, LOG_INFO, "Key successfully received from %s (%s)", c->name, c->hostname); // Call invitation-accepted script environment_t env; @@ -212,6 +218,9 @@ static bool finalize_invitation(connection_t *c, const char *data, uint16_t len) environment_add(&env, "REMOTEADDRESS=%s", address); environment_add(&env, "NAME=%s", myself->name); + free(address); + free(port); + execute_script("invitation-accepted", &env); environment_exit(&env); @@ -237,12 +246,13 @@ static bool receive_invitation_sptps(void *handle, uint8_t type, const void *dat // Recover the filename from the cookie and the key char *fingerprint = ecdsa_get_base64_public_key(invitation_key); - char hashbuf[18 + strlen(fingerprint)]; + const size_t hashbuflen = 18 + strlen(fingerprint); + char *hashbuf = alloca(hashbuflen); char cookie[64]; memcpy(hashbuf, data, 18); - memcpy(hashbuf + 18, fingerprint, sizeof(hashbuf) - 18); - sha512(hashbuf, sizeof(hashbuf), cookie); - b64encode_urlsafe(cookie, cookie, 18); + memcpy(hashbuf + 18, fingerprint, hashbuflen - 18); + sha512(hashbuf, hashbuflen, cookie); + b64encode_tinc_urlsafe(cookie, cookie, 18); free(fingerprint); char filename[PATH_MAX], usedname[PATH_MAX]; @@ -282,13 +292,22 @@ static bool receive_invitation_sptps(void *handle, uint8_t type, const void *dat } // Read the new node's Name from the file - char buf[1024]; - fgets(buf, sizeof(buf), f); + char buf[1024] = ""; - if(*buf) { - buf[strlen(buf) - 1] = 0; + if(!fgets(buf, sizeof(buf), f)) { + logger(DEBUG_ALWAYS, LOG_ERR, "Could not read invitation file %s\n", cookie); + fclose(f); + return false; } + size_t buflen = strlen(buf); + + // Strip whitespace at the end + while(buflen && strchr(" \t\r\n", buf[buflen - 1])) { + buf[--buflen] = 0; + } + + // Split the first line into variable and value len = strcspn(buf, " \t="); char *name = buf + len; name += strspn(name, " \t"); @@ -300,7 +319,8 @@ static bool receive_invitation_sptps(void *handle, uint8_t type, const void *dat buf[len] = 0; - if(!*buf || !*name || strcasecmp(buf, "Name") || !check_id(name)) { + // Check that it is a valid Name + if(!*buf || !*name || strcasecmp(buf, "Name") || !check_id(name) || !strcmp(name, myself->name)) { logger(DEBUG_ALWAYS, LOG_ERR, "Invalid invitation file %s\n", cookie); fclose(f); return false; @@ -317,13 +337,19 @@ static bool receive_invitation_sptps(void *handle, uint8_t type, const void *dat sptps_send_record(&c->sptps, 0, buf, result); } + if(!feof(f)) { + logger(DEBUG_ALWAYS, LOG_ERR, "Could not read invitation file %s\n", cookie); + fclose(f); + return false; + } + sptps_send_record(&c->sptps, 1, buf, 0); fclose(f); unlink(usedname); c->status.invitation_used = true; - logger(DEBUG_CONNECTIONS, LOG_INFO, "Invitation %s succesfully sent to %s (%s)", cookie, c->name, c->hostname); + logger(DEBUG_CONNECTIONS, LOG_INFO, "Invitation %s successfully sent to %s (%s)", cookie, c->name, c->hostname); return true; } @@ -346,6 +372,10 @@ bool id_h(connection_t *c, const char *request) { free(c->name); c->name = xstrdup(""); + if(!c->outgoing) { + send_id(c); + } + return send_request(c, "%d %d %d", ACK, TINC_CTL_VERSION_CURRENT, getpid()); } @@ -369,6 +399,10 @@ bool id_h(connection_t *c, const char *request) { return false; } + if(!c->outgoing) { + send_id(c); + } + if(!send_request(c, "%d %s", ACK, mykey)) { return false; } @@ -382,7 +416,7 @@ bool id_h(connection_t *c, const char *request) { /* Check if identity is a valid name */ - if(!check_id(name)) { + if(!check_id(name) || !strcmp(name, myself->name)) { logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ID", c->name, c->hostname, "invalid name"); return false; @@ -397,10 +431,7 @@ bool id_h(connection_t *c, const char *request) { return false; } } else { - if(c->name) { - free(c->name); - } - + free(c->name); c->name = xstrdup(name); } @@ -414,10 +445,15 @@ bool id_h(connection_t *c, const char *request) { if(bypass_security) { if(!c->config_tree) { - init_configuration(&c->config_tree); + c->config_tree = create_configuration(); } c->allow_request = ACK; + + if(!c->outgoing) { + send_id(c); + } + return send_ack(c); } @@ -426,15 +462,15 @@ bool id_h(connection_t *c, const char *request) { } if(!c->config_tree) { - init_configuration(&c->config_tree); + c->config_tree = create_configuration(); - if(!read_host_config(c->config_tree, c->name)) { + if(!read_host_config(c->config_tree, c->name, false)) { logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s had unknown identity (%s)", c->hostname, c->name); return false; } if(experimental) { - read_ecdsa_public_key(c); + read_ecdsa_public_key(&c->ecdsa, &c->config_tree, c->name); } /* Ignore failures if no key known yet */ @@ -454,33 +490,36 @@ bool id_h(connection_t *c, const char *request) { c->allow_request = METAKEY; + if(!c->outgoing) { + send_id(c); + } + if(c->protocol_minor >= 2) { c->allow_request = ACK; - char label[25 + strlen(myself->name) + strlen(c->name)]; + + const size_t labellen = 25 + strlen(myself->name) + strlen(c->name); + char *label = alloca(labellen); if(c->outgoing) { - snprintf(label, sizeof(label), "tinc TCP key expansion %s %s", myself->name, c->name); + snprintf(label, labellen, "tinc TCP key expansion %s %s", myself->name, c->name); } else { - snprintf(label, sizeof(label), "tinc TCP key expansion %s %s", c->name, myself->name); + snprintf(label, labellen, "tinc TCP key expansion %s %s", c->name, myself->name); } - return sptps_start(&c->sptps, c, c->outgoing, false, myself->connection->ecdsa, c->ecdsa, label, sizeof(label), send_meta_sptps, receive_meta_sptps); + return sptps_start(&c->sptps, c, c->outgoing, false, myself->connection->ecdsa, c->ecdsa, label, labellen, send_meta_sptps, receive_meta_sptps); } else { return send_metakey(c); } } +#ifndef DISABLE_LEGACY bool send_metakey(connection_t *c) { -#ifdef DISABLE_LEGACY - return false; -#else - if(!myself->connection->rsa) { logger(DEBUG_CONNECTIONS, LOG_ERR, "Peer %s (%s) uses legacy protocol which we don't support", c->name, c->hostname); return false; } - if(!read_rsa_public_key(c)) { + if(!read_rsa_public_key(&c->rsa, c->config_tree, c->name)) { return false; } @@ -489,30 +528,32 @@ bool send_metakey(connection_t *c) { by Cipher. */ - int keylen = cipher_keylength(myself->incipher); + size_t keylen = cipher_keylength(myself->incipher); + const char *cipher_name; if(keylen <= 16) { - c->outcipher = cipher_open_by_name("aes-128-cfb"); + cipher_name = "aes-128-cfb"; } else if(keylen <= 24) { - c->outcipher = cipher_open_by_name("aes-192-cfb"); + cipher_name = "aes-192-cfb"; } else { - c->outcipher = cipher_open_by_name("aes-256-cfb"); + cipher_name = "aes-256-cfb"; } - if(!c) { + if(!cipher_open_by_name(&c->outcipher, cipher_name)) { return false; } - c->outbudget = cipher_budget(c->outcipher); + c->outbudget = cipher_budget(&c->outcipher); - if(!(c->outdigest = digest_open_by_name("sha256", -1))) { + if(!digest_open_by_name(&c->outdigest, "sha256", DIGEST_ALGO_SIZE)) { + cipher_close(&c->outcipher); return false; } const size_t len = rsa_size(c->rsa); - char key[len]; - char enckey[len]; - char hexkey[2 * len + 1]; + char *key = alloca(len); + char *enckey = alloca(len); + char *hexkey = alloca(2 * len + 1); /* Create a random key */ @@ -530,7 +571,7 @@ bool send_metakey(connection_t *c) { key[0] &= 0x7F; - if(!cipher_set_key_from_rsa(c->outcipher, key, len, true)) { + if(!cipher_set_key_from_rsa(&c->outcipher, key, len, true)) { return false; } @@ -558,20 +599,15 @@ bool send_metakey(connection_t *c) { /* Send the meta key */ bool result = send_request(c, "%d %d %d %d %d %s", METAKEY, - cipher_get_nid(c->outcipher), - digest_get_nid(c->outdigest), c->outmaclength, + cipher_get_nid(&c->outcipher), + digest_get_nid(&c->outdigest), c->outmaclength, c->outcompression, hexkey); c->status.encryptout = true; return result; -#endif } bool metakey_h(connection_t *c, const char *request) { -#ifdef DISABLE_LEGACY - return false; -#else - if(!myself->connection->rsa) { return false; } @@ -579,8 +615,8 @@ bool metakey_h(connection_t *c, const char *request) { char hexkey[MAX_STRING_SIZE]; int cipher, digest, maclength, compression; const size_t len = rsa_size(myself->connection->rsa); - char enckey[len]; - char key[len]; + char *enckey = alloca(len); + char *key = alloca(len); if(sscanf(request, "%*d %d %d %d %d " MAX_STRING, &cipher, &digest, &maclength, &compression, hexkey) != 5) { logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "METAKEY", c->name, c->hostname); @@ -589,7 +625,7 @@ bool metakey_h(connection_t *c, const char *request) { /* Convert the challenge from hexadecimal back to binary */ - int inlen = hex2bin(hexkey, enckey, sizeof(enckey)); + size_t inlen = hex2bin(hexkey, enckey, len); /* Check if the length of the meta key is all right */ @@ -613,23 +649,25 @@ bool metakey_h(connection_t *c, const char *request) { /* Check and lookup cipher and digest algorithms */ if(cipher) { - if(!(c->incipher = cipher_open_by_nid(cipher)) || !cipher_set_key_from_rsa(c->incipher, key, len, false)) { + if(!cipher_open_by_nid(&c->incipher, cipher) || !cipher_set_key_from_rsa(&c->incipher, key, len, false)) { logger(DEBUG_ALWAYS, LOG_ERR, "Error during initialisation of cipher from %s (%s)", c->name, c->hostname); return false; } } else { - c->incipher = NULL; + logger(DEBUG_ALWAYS, LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "null cipher"); + return false; } - c->inbudget = cipher_budget(c->incipher); + c->inbudget = cipher_budget(&c->incipher); if(digest) { - if(!(c->indigest = digest_open_by_nid(digest, -1))) { + if(!digest_open_by_nid(&c->indigest, digest, DIGEST_ALGO_SIZE)) { logger(DEBUG_ALWAYS, LOG_ERR, "Error during initialisation of digest from %s (%s)", c->name, c->hostname); return false; } } else { - c->indigest = NULL; + logger(DEBUG_ALWAYS, LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "null digest"); + return false; } c->status.decryptin = true; @@ -637,19 +675,13 @@ bool metakey_h(connection_t *c, const char *request) { c->allow_request = CHALLENGE; return send_challenge(c); -#endif } bool send_challenge(connection_t *c) { -#ifdef DISABLE_LEGACY - return false; -#else const size_t len = rsa_size(c->rsa); - char buffer[len * 2 + 1]; + char *buffer = alloca(len * 2 + 1); - if(!c->hischallenge) { - c->hischallenge = xrealloc(c->hischallenge, len); - } + c->hischallenge = xrealloc(c->hischallenge, len); /* Copy random data to the buffer */ @@ -662,61 +694,69 @@ bool send_challenge(connection_t *c) { /* Send the challenge */ return send_request(c, "%d %s", CHALLENGE, buffer); -#endif } bool challenge_h(connection_t *c, const char *request) { -#ifdef DISABLE_LEGACY - return false; -#else - if(!myself->connection->rsa) { return false; } char buffer[MAX_STRING_SIZE]; const size_t len = rsa_size(myself->connection->rsa); - size_t digestlen = digest_length(c->indigest); - char digest[digestlen]; if(sscanf(request, "%*d " MAX_STRING, buffer) != 1) { logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "CHALLENGE", c->name, c->hostname); return false; } - /* Convert the challenge from hexadecimal back to binary */ - - int inlen = hex2bin(buffer, buffer, sizeof(buffer)); - /* Check if the length of the challenge is all right */ - if(inlen != len) { + if(strlen(buffer) != (size_t)len * 2) { logger(DEBUG_ALWAYS, LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong challenge length"); return false; } + c->mychallenge = xrealloc(c->mychallenge, len); + + /* Convert the challenge from hexadecimal back to binary */ + + hex2bin(buffer, c->mychallenge, len); + + /* The rest is done by send_chal_reply() */ + + c->allow_request = CHAL_REPLY; + + if(c->outgoing) { + return send_chal_reply(c); + } else { + return true; + } +} + +bool send_chal_reply(connection_t *c) { + const size_t len = rsa_size(myself->connection->rsa); + size_t digestlen = digest_length(&c->indigest); + char *digest = alloca(digestlen * 2 + 1); + /* Calculate the hash from the challenge we received */ - if(!digest_create(c->indigest, buffer, len, digest)) { + if(!digest_create(&c->indigest, c->mychallenge, len, digest)) { return false; } + free(c->mychallenge); + c->mychallenge = NULL; + /* Convert the hash to a hexadecimal formatted string */ - bin2hex(digest, buffer, digestlen); + bin2hex(digest, digest, digestlen); /* Send the reply */ - c->allow_request = CHAL_REPLY; - - return send_request(c, "%d %s", CHAL_REPLY, buffer); -#endif + return send_request(c, "%d %s", CHAL_REPLY, digest); } bool chal_reply_h(connection_t *c, const char *request) { -#ifdef DISABLE_LEGACY - return false; -#else char hishash[MAX_STRING_SIZE]; if(sscanf(request, "%*d " MAX_STRING, hishash) != 1) { @@ -727,11 +767,11 @@ bool chal_reply_h(connection_t *c, const char *request) { /* Convert the hash to binary format */ - int inlen = hex2bin(hishash, hishash, sizeof(hishash)); + size_t inlen = hex2bin(hishash, hishash, sizeof(hishash)); /* Check if the length of the hash is all right */ - if(inlen != digest_length(c->outdigest)) { + if(inlen != digest_length(&c->outdigest)) { logger(DEBUG_ALWAYS, LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong challenge reply length"); return false; } @@ -739,7 +779,7 @@ bool chal_reply_h(connection_t *c, const char *request) { /* Verify the hash */ - if(!digest_verify(c->outdigest, c->hischallenge, rsa_size(c->rsa), hishash)) { + if(!digest_verify(&c->outdigest, c->hischallenge, rsa_size(c->rsa), hishash)) { logger(DEBUG_ALWAYS, LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong challenge reply"); return false; } @@ -752,14 +792,14 @@ bool chal_reply_h(connection_t *c, const char *request) { c->hischallenge = NULL; c->allow_request = ACK; + if(!c->outgoing) { + send_chal_reply(c); + } + return send_ack(c); -#endif } static bool send_upgrade(connection_t *c) { -#ifdef DISABLE_LEGACY - return false; -#else /* Special case when protocol_minor is 1: the other end is Ed25519 capable, * but doesn't know our key yet. So send it now. */ @@ -772,8 +812,46 @@ static bool send_upgrade(connection_t *c) { bool result = send_request(c, "%d %s", ACK, pubkey); free(pubkey); return result; -#endif } +#else +bool send_metakey(connection_t *c) { + (void)c; + return false; +} + +bool metakey_h(connection_t *c, const char *request) { + (void)c; + (void)request; + return false; +} + +bool send_challenge(connection_t *c) { + (void)c; + return false; +} + +bool challenge_h(connection_t *c, const char *request) { + (void)c; + (void)request; + return false; +} + +bool send_chal_reply(connection_t *c) { + (void)c; + return false; +} + +bool chal_reply_h(connection_t *c, const char *request) { + (void)c; + (void)request; + return false; +} + +static bool send_upgrade(connection_t *c) { + (void)c; + return false; +} +#endif bool send_ack(connection_t *c) { if(c->protocol_minor == 1) { @@ -789,7 +867,7 @@ bool send_ack(connection_t *c) { /* Estimate weight */ gettimeofday(&now, NULL); - c->estimated_weight = (now.tv_sec - c->start.tv_sec) * 1000 + (now.tv_usec - c->start.tv_usec) / 1000; + c->estimated_weight = (int)((now.tv_sec - c->start.tv_sec) * 1000 + (now.tv_usec - c->start.tv_usec) / 1000); /* Check some options */ @@ -801,7 +879,7 @@ bool send_ack(connection_t *c) { c->options |= OPTION_TCPONLY | OPTION_INDIRECT; } - if(myself->options & OPTION_PMTU_DISCOVERY) { + if(myself->options & OPTION_PMTU_DISCOVERY && !(c->options & OPTION_TCPONLY)) { c->options |= OPTION_PMTU_DISCOVERY; } @@ -813,10 +891,10 @@ bool send_ack(connection_t *c) { } if(!get_config_int(lookup_config(c->config_tree, "Weight"), &c->estimated_weight)) { - get_config_int(lookup_config(config_tree, "Weight"), &c->estimated_weight); + get_config_int(lookup_config(&config_tree, "Weight"), &c->estimated_weight); } - return send_request(c, "%d %s %d %x", ACK, myport, c->estimated_weight, (c->options & 0xffffff) | (experimental ? (PROT_MINOR << 24) : 0)); + return send_request(c, "%d %s %d %x", ACK, myport.udp, c->estimated_weight, (c->options & 0xffffff) | (experimental ? (PROT_MINOR << 24) : 0)); } static void send_everything(connection_t *c) { @@ -834,19 +912,19 @@ static void send_everything(connection_t *c) { } if(tunnelserver) { - for splay_each(subnet_t, s, myself->subnet_tree) { + for splay_each(subnet_t, s, &myself->subnet_tree) { send_add_subnet(c, s); } return; } - for splay_each(node_t, n, node_tree) { - for splay_each(subnet_t, s, n->subnet_tree) { + for splay_each(node_t, n, &node_tree) { + for splay_each(subnet_t, s, &n->subnet_tree) { send_add_subnet(c, s); } - for splay_each(edge_t, e, n->edge_tree) { + for splay_each(edge_t, e, &n->edge_tree) { send_add_edge(c, e); } } @@ -860,7 +938,7 @@ static bool upgrade_h(connection_t *c, const char *request) { return false; } - if(ecdsa_active(c->ecdsa) || read_ecdsa_public_key(c)) { + if(ecdsa_active(c->ecdsa) || read_ecdsa_public_key(&c->ecdsa, &c->config_tree, c->name)) { char *knownkey = ecdsa_get_base64_public_key(c->ecdsa); bool different = strcmp(knownkey, pubkey); free(knownkey); @@ -953,7 +1031,7 @@ bool ack_h(connection_t *c, const char *request) { n->mtu = mtu; } - if(get_config_int(lookup_config(config_tree, "PMTU"), &mtu) && mtu < n->mtu) { + if(get_config_int(lookup_config(&config_tree, "PMTU"), &mtu) && mtu < n->mtu) { n->mtu = mtu; } @@ -989,7 +1067,7 @@ bool ack_h(connection_t *c, const char *request) { if(getsockname(c->socket, &local_sa.sa, &local_salen) < 0) { logger(DEBUG_ALWAYS, LOG_WARNING, "Could not get local socket address for connection with %s", c->name); } else { - sockaddr_setport(&local_sa, myport); + sockaddr_setport(&local_sa, myport.udp); c->edge->local_address = local_sa; }