X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol_auth.c;h=93fe23ea1692053309204c6f3dab93a31ae02166;hp=48166105874ec1f2fc75db608d26ce922ff02558;hb=5a132550deb58473285e5f91705d286aef47be71;hpb=591c38eb38dbf0851bdebdd50b08d1bcbf6d7b0f diff --git a/src/protocol_auth.c b/src/protocol_auth.c index 48166105..93fe23ea 100644 --- a/src/protocol_auth.c +++ b/src/protocol_auth.c @@ -22,14 +22,10 @@ #include "system.h" -#include -#include -#include -#include - -#include "avl_tree.h" +#include "splay_tree.h" #include "conf.h" #include "connection.h" +#include "crypto.h" #include "edge.h" #include "graph.h" #include "logger.h" @@ -37,24 +33,25 @@ #include "netutl.h" #include "node.h" #include "protocol.h" +#include "rsa.h" #include "utils.h" #include "xalloc.h" -bool send_id(connection_t *c) -{ +bool send_id(connection_t *c) { cp(); + gettimeofday(&c->start, NULL); + return send_request(c, "%d %s %d", ID, myself->connection->name, myself->connection->protocol_version); } -bool id_h(connection_t *c) -{ +bool id_h(connection_t *c, char *request) { char name[MAX_STRING_SIZE]; cp(); - if(sscanf(c->buffer, "%*d " MAX_STRING " %d", name, &c->protocol_version) != 2) { + if(sscanf(request, "%*d " MAX_STRING " %d", name, &c->protocol_version) != 2) { logger(LOG_ERR, _("Got bad %s from %s (%s)"), "ID", c->name, c->hostname); return false; @@ -116,28 +113,23 @@ bool id_h(connection_t *c) return send_metakey(c); } -bool send_metakey(connection_t *c) -{ - char *buffer; - int len; - bool x; +bool send_metakey(connection_t *c) { + size_t len = rsa_size(&c->rsa); + char key[len]; + char enckey[len]; + char hexkey[2 * len + 1]; cp(); - len = RSA_size(c->rsa_key); - - /* Allocate buffers for the meta key */ - - buffer = alloca(2 * len + 1); + if(!cipher_open_blowfish_ofb(&c->outcipher)) + return false; - c->outkey = xrealloc(c->outkey, len); + if(!digest_open_sha1(&c->outdigest)) + return false; - if(!c->outctx) - c->outctx = xmalloc_and_zero(sizeof(*c->outctx)); - cp(); - /* Copy random data to the buffer */ + /* Create a random key */ - RAND_pseudo_bytes((unsigned char *)c->outkey, len); + randomize(key, len); /* The message we send must be smaller than the modulus of the RSA key. By definition, for a key of k bits, the following formula holds: @@ -149,13 +141,14 @@ bool send_metakey(connection_t *c) This can be done by setting the most significant bit to zero. */ - c->outkey[0] &= 0x7F; + key[0] &= 0x7F; + + cipher_set_key_from_rsa(&c->outcipher, key, len, true); ifdebug(SCARY_THINGS) { - bin2hex(c->outkey, buffer, len); - buffer[len * 2] = '\0'; - logger(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"), - buffer); + bin2hex(key, hexkey, len); + hexkey[len * 2] = '\0'; + logger(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"), hexkey); } /* Encrypt the random data @@ -165,161 +158,96 @@ bool send_metakey(connection_t *c) with a length equal to that of the modulus of the RSA key. */ - if(RSA_public_encrypt(len, (unsigned char *)c->outkey, (unsigned char *)buffer, c->rsa_key, RSA_NO_PADDING) != len) { - logger(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), - c->name, c->hostname); + if(!rsa_public_encrypt(&c->rsa, key, len, enckey)) { + logger(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), c->name, c->hostname); return false; } /* Convert the encrypted random data to a hexadecimal formatted string */ - bin2hex(buffer, buffer, len); - buffer[len * 2] = '\0'; + bin2hex(enckey, hexkey, len); + hexkey[len * 2] = '\0'; /* Send the meta key */ - x = send_request(c, "%d %d %d %d %d %s", METAKEY, - c->outcipher ? c->outcipher->nid : 0, - c->outdigest ? c->outdigest->type : 0, c->outmaclength, - c->outcompression, buffer); - - /* Further outgoing requests are encrypted with the key we just generated */ - - if(c->outcipher) { - if(!EVP_EncryptInit(c->outctx, c->outcipher, - (unsigned char *)c->outkey + len - c->outcipher->key_len, - (unsigned char *)c->outkey + len - c->outcipher->key_len - - c->outcipher->iv_len)) { - logger(LOG_ERR, _("Error during initialisation of cipher for %s (%s): %s"), - c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); - return false; - } - - c->status.encryptout = true; - } - - return x; + bool result = send_request(c, "%d %d %d %d %d %s", METAKEY, + cipher_get_nid(&c->outcipher), + digest_get_nid(&c->outdigest), c->outmaclength, + c->outcompression, hexkey); + + c->status.encryptout = true; + return result; } -bool metakey_h(connection_t *c) -{ - char buffer[MAX_STRING_SIZE]; +bool metakey_h(connection_t *c, char *request) { + char hexkey[MAX_STRING_SIZE]; int cipher, digest, maclength, compression; - int len; + size_t len = rsa_size(&myself->connection->rsa); + char enckey[len]; + char key[len]; cp(); - if(sscanf(c->buffer, "%*d %d %d %d %d " MAX_STRING, &cipher, &digest, &maclength, &compression, buffer) != 5) { - logger(LOG_ERR, _("Got bad %s from %s (%s)"), "METAKEY", c->name, - c->hostname); + if(sscanf(request, "%*d %d %d %d %d " MAX_STRING, &cipher, &digest, &maclength, &compression, hexkey) != 5) { + logger(LOG_ERR, _("Got bad %s from %s (%s)"), "METAKEY", c->name, c->hostname); return false; } - len = RSA_size(myself->connection->rsa_key); - /* Check if the length of the meta key is all right */ - if(strlen(buffer) != len * 2) { + if(strlen(hexkey) != len * 2) { logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, c->hostname, "wrong keylength"); return false; } - /* Allocate buffers for the meta key */ - - c->inkey = xrealloc(c->inkey, len); - - if(!c->inctx) - c->inctx = xmalloc_and_zero(sizeof(*c->inctx)); - /* Convert the challenge from hexadecimal back to binary */ - hex2bin(buffer, buffer, len); + hex2bin(hexkey, enckey, len); /* Decrypt the meta key */ - if(RSA_private_decrypt(len, (unsigned char *)buffer, (unsigned char *)c->inkey, myself->connection->rsa_key, RSA_NO_PADDING) != len) { /* See challenge() */ - logger(LOG_ERR, _("Error during decryption of meta key for %s (%s)"), - c->name, c->hostname); + if(!rsa_private_decrypt(&myself->connection->rsa, enckey, len, key)) { + logger(LOG_ERR, _("Error during decryption of meta key for %s (%s)"), c->name, c->hostname); return false; } ifdebug(SCARY_THINGS) { - bin2hex(c->inkey, buffer, len); - buffer[len * 2] = '\0'; - logger(LOG_DEBUG, _("Received random meta key (unencrypted): %s"), buffer); + bin2hex(key, hexkey, len); + hexkey[len * 2] = '\0'; + logger(LOG_DEBUG, _("Received random meta key (unencrypted): %s"), hexkey); } - /* All incoming requests will now be encrypted. */ - /* Check and lookup cipher and digest algorithms */ - if(cipher) { - c->incipher = EVP_get_cipherbynid(cipher); - - if(!c->incipher) { - logger(LOG_ERR, _("%s (%s) uses unknown cipher!"), c->name, c->hostname); - return false; - } - - if(!EVP_DecryptInit(c->inctx, c->incipher, - (unsigned char *)c->inkey + len - c->incipher->key_len, - (unsigned char *)c->inkey + len - c->incipher->key_len - - c->incipher->iv_len)) { - logger(LOG_ERR, _("Error during initialisation of cipher from %s (%s): %s"), - c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); - return false; - } - - c->status.decryptin = true; - } else { - c->incipher = NULL; + if(!cipher_open_by_nid(&c->incipher, cipher) || !cipher_set_key_from_rsa(&c->incipher, key, len, false)) { + logger(LOG_ERR, _("Error during initialisation of cipher from %s (%s)"), c->name, c->hostname); + return false; } - c->inmaclength = maclength; - - if(digest) { - c->indigest = EVP_get_digestbynid(digest); - - if(!c->indigest) { - logger(LOG_ERR, _("Node %s (%s) uses unknown digest!"), c->name, c->hostname); - return false; - } - - if(c->inmaclength > c->indigest->md_size || c->inmaclength < 0) { - logger(LOG_ERR, _("%s (%s) uses bogus MAC length!"), c->name, c->hostname); - return false; - } - } else { - c->indigest = NULL; + if(!digest_open_by_nid(&c->indigest, digest)) { + logger(LOG_ERR, _("Error during initialisation of digest from %s (%s)"), c->name, c->hostname); + return false; } - c->incompression = compression; + c->status.decryptin = true; c->allow_request = CHALLENGE; return send_challenge(c); } -bool send_challenge(connection_t *c) -{ - char *buffer; - int len; +bool send_challenge(connection_t *c) { + size_t len = rsa_size(&c->rsa); + char buffer[len * 2 + 1]; cp(); - /* CHECKME: what is most reasonable value for len? */ - - len = RSA_size(c->rsa_key); - - /* Allocate buffers for the challenge */ - - buffer = alloca(2 * len + 1); - - c->hischallenge = xrealloc(c->hischallenge, len); + if(!c->hischallenge) + c->hischallenge = xrealloc(c->hischallenge, len); /* Copy random data to the buffer */ - RAND_pseudo_bytes((unsigned char *)c->hischallenge, len); + randomize(c->hischallenge, len); /* Convert to hex */ @@ -331,80 +259,54 @@ bool send_challenge(connection_t *c) return send_request(c, "%d %s", CHALLENGE, buffer); } -bool challenge_h(connection_t *c) -{ +bool challenge_h(connection_t *c, char *request) { char buffer[MAX_STRING_SIZE]; - int len; + size_t len = rsa_size(&myself->connection->rsa); + size_t digestlen = digest_length(&c->outdigest); + char digest[digestlen]; cp(); - if(sscanf(c->buffer, "%*d " MAX_STRING, buffer) != 1) { - logger(LOG_ERR, _("Got bad %s from %s (%s)"), "CHALLENGE", c->name, - c->hostname); + if(sscanf(request, "%*d " MAX_STRING, buffer) != 1) { + logger(LOG_ERR, _("Got bad %s from %s (%s)"), "CHALLENGE", c->name, c->hostname); return false; } - len = RSA_size(myself->connection->rsa_key); - /* Check if the length of the challenge is all right */ if(strlen(buffer) != len * 2) { - logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, - c->hostname, "wrong challenge length"); + logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, c->hostname, "wrong challenge length"); return false; } - /* Allocate buffers for the challenge */ - - c->mychallenge = xrealloc(c->mychallenge, len); - /* Convert the challenge from hexadecimal back to binary */ - hex2bin(buffer, c->mychallenge, len); + hex2bin(buffer, buffer, len); c->allow_request = CHAL_REPLY; - /* Rest is done by send_chal_reply() */ - - return send_chal_reply(c); -} - -bool send_chal_reply(connection_t *c) -{ - char hash[EVP_MAX_MD_SIZE * 2 + 1]; - EVP_MD_CTX ctx; - cp(); /* Calculate the hash from the challenge we received */ - if(!EVP_DigestInit(&ctx, c->indigest) - || !EVP_DigestUpdate(&ctx, c->mychallenge, RSA_size(myself->connection->rsa_key)) - || !EVP_DigestFinal(&ctx, (unsigned char *)hash, NULL)) { - logger(LOG_ERR, _("Error during calculation of response for %s (%s): %s"), - c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); - return false; - } + digest_create(&c->indigest, buffer, len, digest); /* Convert the hash to a hexadecimal formatted string */ - bin2hex(hash, hash, c->indigest->md_size); - hash[c->indigest->md_size * 2] = '\0'; + bin2hex(digest, buffer, digestlen); + buffer[digestlen * 2] = '\0'; /* Send the reply */ - return send_request(c, "%d %s", CHAL_REPLY, hash); + return send_request(c, "%d %s", CHAL_REPLY, buffer); } -bool chal_reply_h(connection_t *c) -{ +bool chal_reply_h(connection_t *c, char *request) { char hishash[MAX_STRING_SIZE]; - char myhash[EVP_MAX_MD_SIZE]; - EVP_MD_CTX ctx; cp(); - if(sscanf(c->buffer, "%*d " MAX_STRING, hishash) != 1) { + if(sscanf(request, "%*d " MAX_STRING, hishash) != 1) { logger(LOG_ERR, _("Got bad %s from %s (%s)"), "CHAL_REPLY", c->name, c->hostname); return false; @@ -412,38 +314,19 @@ bool chal_reply_h(connection_t *c) /* Check if the length of the hash is all right */ - if(strlen(hishash) != c->outdigest->md_size * 2) { - logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, - c->hostname, _("wrong challenge reply length")); + if(strlen(hishash) != digest_length(&c->outdigest) * 2) { + logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, c->hostname, _("wrong challenge reply length")); return false; } /* Convert the hash to binary format */ - hex2bin(hishash, hishash, c->outdigest->md_size); + hex2bin(hishash, hishash, digest_length(&c->outdigest)); - /* Calculate the hash from the challenge we sent */ - - if(!EVP_DigestInit(&ctx, c->outdigest) - || !EVP_DigestUpdate(&ctx, c->hischallenge, RSA_size(c->rsa_key)) - || !EVP_DigestFinal(&ctx, (unsigned char *)myhash, NULL)) { - logger(LOG_ERR, _("Error during calculation of response from %s (%s): %s"), - c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); - return false; - } - - /* Verify the incoming hash with the calculated hash */ - - if(memcmp(hishash, myhash, c->outdigest->md_size)) { - logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, - c->hostname, _("wrong challenge reply")); - - ifdebug(SCARY_THINGS) { - bin2hex(myhash, hishash, SHA_DIGEST_LENGTH); - hishash[SHA_DIGEST_LENGTH * 2] = '\0'; - logger(LOG_DEBUG, _("Expected challenge reply: %s"), hishash); - } + /* Verify the hash */ + if(!digest_verify(&c->outdigest, c->hischallenge, rsa_size(&c->rsa), hishash)) { + logger(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name, c->hostname, _("wrong challenge reply")); return false; } @@ -451,13 +334,14 @@ bool chal_reply_h(connection_t *c) Send an acknowledgement with the rest of the information needed. */ + free(c->hischallenge); + c->hischallenge = NULL; c->allow_request = ACK; return send_ack(c); } -bool send_ack(connection_t *c) -{ +bool send_ack(connection_t *c) { /* ACK message contains rest of the information the other end needs to create node_t and edge_t structures. */ @@ -487,9 +371,8 @@ bool send_ack(connection_t *c) return send_request(c, "%d %s %d %lx", ACK, myport, c->estimated_weight, c->options); } -static void send_everything(connection_t *c) -{ - avl_node_t *node, *node2; +static void send_everything(connection_t *c) { + splay_node_t *node, *node2; node_t *n; subnet_t *s; edge_t *e; @@ -520,8 +403,7 @@ static void send_everything(connection_t *c) } } -bool ack_h(connection_t *c) -{ +bool ack_h(connection_t *c, char *request) { char hisport[MAX_STRING_SIZE]; char *hisaddress, *dummy; int weight, mtu; @@ -530,7 +412,7 @@ bool ack_h(connection_t *c) cp(); - if(sscanf(c->buffer, "%*d " MAX_STRING " %d %lx", hisport, &weight, &options) != 3) { + if(sscanf(request, "%*d " MAX_STRING " %d %lx", hisport, &weight, &options) != 3) { logger(LOG_ERR, _("Got bad %s from %s (%s)"), "ACK", c->name, c->hostname); return false; @@ -547,8 +429,17 @@ bool ack_h(connection_t *c) } else { if(n->connection) { /* Oh dear, we already have a connection to this node. */ - ifdebug(CONNECTIONS) logger(LOG_DEBUG, _("Established a second connection with %s (%s), closing old connection"), - n->name, n->hostname); + ifdebug(CONNECTIONS) logger(LOG_DEBUG, _("Established a second connection with %s (%s), closing old connection"), n->connection->name, n->connection->hostname); + + if(n->connection->outgoing) { + if(c->outgoing) + logger(LOG_WARNING, _("Two outgoing connections to the same node!")); + else + c->outgoing = n->connection->outgoing; + + n->connection->outgoing = NULL; + } + terminate_connection(n->connection, false); /* Run graph algorithm to purge key and make sure up/down scripts are rerun with new IP addresses and stuff */ graph();