From 046158a216e78a0412186ec8463157f6bce45d5d Mon Sep 17 00:00:00 2001 From: Guus Sliepen Date: Thu, 11 Dec 2008 14:44:44 +0000 Subject: [PATCH] Use the crypto wrappers again instead of calling OpenSSL directly. This theoretically allows other cryptographic libraries to be used, and it improves the readability of the code. --- src/connection.c | 11 +- src/connection.h | 27 ++--- src/meta.c | 29 +++-- src/net_packet.c | 65 ++++-------- src/net_setup.c | 251 +++++++++++++------------------------------ src/node.c | 11 +- src/node.h | 12 +-- src/protocol_auth.c | 253 ++++++++++++-------------------------------- src/protocol_key.c | 91 ++++++---------- src/tincd.c | 18 +--- 10 files changed, 240 insertions(+), 528 deletions(-) diff --git a/src/connection.c b/src/connection.c index 06f51b50..84d2ac4d 100644 --- a/src/connection.c +++ b/src/connection.c @@ -23,6 +23,7 @@ #include "system.h" #include "splay_tree.h" +#include "cipher.h" #include "conf.h" #include "list.h" #include "logger.h" @@ -73,14 +74,8 @@ void free_connection(connection_t *c) { if(c->hostname) free(c->hostname); - if(c->inkey) - free(c->inkey); - - if(c->outkey) - free(c->outkey); - - if(c->mychallenge) - free(c->mychallenge); + cipher_close(&c->incipher); + cipher_close(&c->outcipher); if(c->hischallenge) free(c->hischallenge); diff --git a/src/connection.h b/src/connection.h index ddff03bb..ca71cad9 100644 --- a/src/connection.h +++ b/src/connection.h @@ -23,11 +23,11 @@ #ifndef __TINC_CONNECTION_H__ #define __TINC_CONNECTION_H__ -#include -#include - #include +#include "cipher.h" +#include "digest.h" +#include "rsa.h" #include "splay_tree.h" #define OPTION_INDIRECT 0x0001 @@ -72,23 +72,18 @@ typedef struct connection_t { struct node_t *node; /* node associated with the other end */ struct edge_t *edge; /* edge associated with this connection */ - RSA *rsa_key; /* his public/private key */ - const EVP_CIPHER *incipher; /* Cipher he will use to send data to us */ - const EVP_CIPHER *outcipher; /* Cipher we will use to send data to him */ - EVP_CIPHER_CTX *inctx; /* Context of encrypted meta data that will come from him to us */ - EVP_CIPHER_CTX *outctx; /* Context of encrypted meta data that will be sent from us to him */ - char *inkey; /* His symmetric meta key + iv */ - char *outkey; /* Our symmetric meta key + iv */ - int inkeylength; /* Length of his key + iv */ - int outkeylength; /* Length of our key + iv */ - const EVP_MD *indigest; - const EVP_MD *outdigest; + rsa_t rsa; /* his public/private key */ + cipher_t incipher; /* Cipher he will use to send data to us */ + cipher_t outcipher; /* Cipher we will use to send data to him */ + digest_t indigest; + digest_t outdigest; + int inmaclength; int outmaclength; int incompression; int outcompression; - char *mychallenge; /* challenge we received from him */ - char *hischallenge; /* challenge we sent to him */ + + char *hischallenge; /* The challenge we sent to him */ struct bufferevent *buffer; /* buffer events on this metadata connection */ struct event inevent; /* input event on this metadata connection */ diff --git a/src/meta.c b/src/meta.c index cb4b03e1..aaa5c30c 100644 --- a/src/meta.c +++ b/src/meta.c @@ -22,10 +22,8 @@ #include "system.h" -#include -#include - #include "splay_tree.h" +#include "cipher.h" #include "connection.h" #include "logger.h" #include "meta.h" @@ -35,8 +33,6 @@ #include "xalloc.h" bool send_meta(connection_t *c, const char *buffer, int length) { - int outlen; - int result; cp(); ifdebug(META) logger(LOG_DEBUG, _("Sending %d bytes of metadata to %s (%s)"), length, @@ -45,11 +41,11 @@ bool send_meta(connection_t *c, const char *buffer, int length) { /* Add our data to buffer */ if(c->status.encryptout) { char outbuf[length]; + size_t outlen = length; - result = EVP_EncryptUpdate(c->outctx, (unsigned char *)outbuf, &outlen, (unsigned char *)buffer, length); - if(!result || outlen != length) { - logger(LOG_ERR, _("Error while encrypting metadata to %s (%s): %s"), - c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); + if(!cipher_encrypt(&c->outcipher, buffer, length, outbuf, &outlen, false) || outlen != length) { + logger(LOG_ERR, _("Error while encrypting metadata to %s (%s)"), + c->name, c->hostname); return false; } @@ -80,7 +76,7 @@ void broadcast_meta(connection_t *from, const char *buffer, int length) { } bool receive_meta(connection_t *c) { - int result, inlen, outlen; + size_t inlen; char inbuf[MAXBUFSIZE]; char *bufp = inbuf, *endp; @@ -115,12 +111,13 @@ bool receive_meta(connection_t *c) { inlen -= endp - bufp; bufp = endp; } else { + size_t outlen = inlen; ifdebug(META) logger(LOG_DEBUG, _("Received encrypted %d bytes"), inlen); evbuffer_expand(c->buffer->input, c->buffer->input->off + inlen); - result = EVP_DecryptUpdate(c->inctx, (unsigned char *)c->buffer->input->buffer + c->buffer->input->off, &outlen, (unsigned char *)bufp, inlen); - if(!result || outlen != inlen) { - logger(LOG_ERR, _("Error while decrypting metadata from %s (%s): %s"), - c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); + + if(!cipher_decrypt(&c->incipher, bufp, inlen, c->buffer->input->buffer + c->buffer->input->off, &outlen, false) || inlen != outlen) { + logger(LOG_ERR, _("Error while decrypting metadata from %s (%s)"), + c->name, c->hostname); return false; } c->buffer->input->off += inlen; @@ -146,8 +143,10 @@ bool receive_meta(connection_t *c) { char *request = evbuffer_readline(c->buffer->input); if(request) { - receive_request(c, request); + bool result = receive_request(c, request); free(request); + if(!result) + return false; continue; } else { break; diff --git a/src/net_packet.c b/src/net_packet.c index 2a86d657..eee3972e 100644 --- a/src/net_packet.c +++ b/src/net_packet.c @@ -22,18 +22,15 @@ #include "system.h" -#include -#include -#include -#include -#include - #include #include LZO1X_H #include "splay_tree.h" +#include "cipher.h" #include "conf.h" #include "connection.h" +#include "crypto.h" +#include "digest.h" #include "device.h" #include "ethernet.h" #include "graph.h" @@ -52,7 +49,6 @@ #endif int keylifetime = 0; -EVP_CIPHER_CTX packet_ctx; static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS]; static void send_udppacket(node_t *, vpn_packet_t *); @@ -85,7 +81,7 @@ static void send_mtu_probe_handler(int fd, short events, void *data) { len = 64; memset(packet.data, 0, 14); - RAND_pseudo_bytes(packet.data + 14, len - 14); + randomize(packet.data + 14, len - 14); packet.len = len; ifdebug(TRAFFIC) logger(LOG_INFO, _("Sending MTU probe length %d to %s (%s)"), len, n->name, n->hostname); @@ -168,15 +164,14 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 }; int nextpkt = 0; vpn_packet_t *outpkt = pkt[0]; - int outlen, outpad; - unsigned char hmac[EVP_MAX_MD_SIZE]; + size_t outlen; int i; cp(); /* Check packet length */ - if(inpkt->len < sizeof(inpkt->seqno) + myself->maclength) { + if(inpkt->len < sizeof(inpkt->seqno) + digest_length(&myself->digest)) { ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got too short packet from %s (%s)"), n->name, n->hostname); return; @@ -184,33 +179,23 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { /* Check the message authentication code */ - if(myself->digest && myself->maclength) { - inpkt->len -= myself->maclength; - HMAC(myself->digest, myself->key, myself->keylength, - (unsigned char *) &inpkt->seqno, inpkt->len, (unsigned char *)hmac, NULL); - - if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len, myself->maclength)) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got unauthenticated packet from %s (%s)"), - n->name, n->hostname); - return; - } + if(digest_active(&myself->digest) && !digest_verify(&myself->digest, &inpkt->seqno, inpkt->len, &inpkt->seqno + inpkt->len)) { + ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got unauthenticated packet from %s (%s)"), n->name, n->hostname); + return; } /* Decrypt the packet */ - if(myself->cipher) { + if(cipher_active(&myself->cipher)) { outpkt = pkt[nextpkt++]; + outlen = MAXSIZE; - if(!EVP_DecryptInit_ex(&packet_ctx, NULL, NULL, NULL, NULL) - || !EVP_DecryptUpdate(&packet_ctx, (unsigned char *) &outpkt->seqno, &outlen, - (unsigned char *) &inpkt->seqno, inpkt->len) - || !EVP_DecryptFinal_ex(&packet_ctx, (unsigned char *) &outpkt->seqno + outlen, &outpad)) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Error decrypting packet from %s (%s): %s"), - n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL)); + if(!cipher_decrypt(&myself->cipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) { + ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Error decrypting packet from %s (%s)"), n->name, n->hostname); return; } - outpkt->len = outlen + outpad; + outpkt->len = outlen; inpkt = outpkt; } @@ -283,7 +268,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { int nextpkt = 0; vpn_packet_t *outpkt; int origlen; - int outlen, outpad; + size_t outlen; vpn_packet_t *copy; static int priority = 0; int origpriority; @@ -339,28 +324,24 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { /* Encrypt the packet */ - if(n->cipher) { + if(cipher_active(&n->cipher)) { outpkt = pkt[nextpkt++]; + outlen = MAXSIZE; - if(!EVP_EncryptInit_ex(&n->packet_ctx, NULL, NULL, NULL, NULL) - || !EVP_EncryptUpdate(&n->packet_ctx, (unsigned char *) &outpkt->seqno, &outlen, - (unsigned char *) &inpkt->seqno, inpkt->len) - || !EVP_EncryptFinal_ex(&n->packet_ctx, (unsigned char *) &outpkt->seqno + outlen, &outpad)) { - ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while encrypting packet to %s (%s): %s"), - n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL)); + if(!cipher_encrypt(&n->cipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) { + ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while encrypting packet to %s (%s)"), n->name, n->hostname); goto end; } - outpkt->len = outlen + outpad; + outpkt->len = outlen; inpkt = outpkt; } /* Add the message authentication code */ - if(n->digest && n->maclength) { - HMAC(n->digest, n->key, n->keylength, (unsigned char *) &inpkt->seqno, - inpkt->len, (unsigned char *) &inpkt->seqno + inpkt->len, NULL); - inpkt->len += n->maclength; + if(digest_active(&n->digest)) { + digest_create(&n->digest, &inpkt->seqno, inpkt->len, &inpkt->seqno + inpkt->len); + inpkt->len += digest_length(&n->digest); } /* Determine which socket we have to use */ diff --git a/src/net_setup.c b/src/net_setup.c index b8fb4f02..033bf376 100644 --- a/src/net_setup.c +++ b/src/net_setup.c @@ -22,17 +22,13 @@ #include "system.h" -#include -#include -#include -#include -#include - #include "splay_tree.h" +#include "cipher.h" #include "conf.h" #include "connection.h" #include "control.h" #include "device.h" +#include "digest.h" #include "graph.h" #include "logger.h" #include "net.h" @@ -40,6 +36,7 @@ #include "process.h" #include "protocol.h" #include "route.h" +#include "rsa.h" #include "subnet.h" #include "utils.h" #include "xalloc.h" @@ -50,125 +47,66 @@ static struct event device_ev; bool read_rsa_public_key(connection_t *c) { FILE *fp; char *fname; - char *key; + char *n; + bool result; cp(); - if(!c->rsa_key) { - c->rsa_key = RSA_new(); -// RSA_blinding_on(c->rsa_key, NULL); - } - /* First, check for simple PublicKey statement */ - if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) { - BN_hex2bn(&c->rsa_key->n, key); - BN_hex2bn(&c->rsa_key->e, "FFFF"); - free(key); - return true; + if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &n)) { + result = rsa_set_hex_public_key(&c->rsa, n, "FFFF"); + free(n); + return result; } /* Else, check for PublicKeyFile statement and read it */ - if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) { - fp = fopen(fname, "r"); - - if(!fp) { - logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"), - fname, strerror(errno)); - free(fname); - return false; - } - - free(fname); - c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL); - fclose(fp); - - if(c->rsa_key) - return true; /* Woohoo. */ + if(!get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) + asprintf(&fname, "%s/hosts/%s", confbase, c->name); - /* If it fails, try PEM_read_RSA_PUBKEY. */ - fp = fopen(fname, "r"); - - if(!fp) { - logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"), - fname, strerror(errno)); - free(fname); - return false; - } - - free(fname); - c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL); - fclose(fp); - - if(c->rsa_key) { -// RSA_blinding_on(c->rsa_key, NULL); - return true; - } + fp = fopen(fname, "r"); - logger(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"), + if(!fp) { + logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"), fname, strerror(errno)); + free(fname); return false; } - /* Else, check if a harnessed public key is in the config file */ - - asprintf(&fname, "%s/hosts/%s", confbase, c->name); - fp = fopen(fname, "r"); - - if(fp) { - c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL); - fclose(fp); - } - - free(fname); - - if(c->rsa_key) - return true; - - /* Try again with PEM_read_RSA_PUBKEY. */ - - asprintf(&fname, "%s/hosts/%s", confbase, c->name); - fp = fopen(fname, "r"); - - if(fp) { - c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL); -// RSA_blinding_on(c->rsa_key, NULL); - fclose(fp); - } + result = rsa_read_pem_public_key(&c->rsa, fp); + fclose(fp); + if(!result) + logger(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"), fname, strerror(errno)); free(fname); - - if(c->rsa_key) - return true; - - logger(LOG_ERR, _("No public key for %s specified!"), c->name); - - return false; + return result; } -bool read_rsa_private_key(void) { +bool read_rsa_private_key() { FILE *fp; - char *fname, *key, *pubkey; - struct stat s; + char *fname; + char *n, *d; + bool result; cp(); - if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) { - if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &pubkey)) { + /* First, check for simple PrivateKey statement */ + + if(get_config_string(lookup_config(config_tree, "PrivateKey"), &d)) { + if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &n)) { logger(LOG_ERR, _("PrivateKey used but no PublicKey found!")); + free(d); return false; } - myself->connection->rsa_key = RSA_new(); -// RSA_blinding_on(myself->connection->rsa_key, NULL); - BN_hex2bn(&myself->connection->rsa_key->d, key); - BN_hex2bn(&myself->connection->rsa_key->n, pubkey); - BN_hex2bn(&myself->connection->rsa_key->e, "FFFF"); - free(key); - free(pubkey); + result = rsa_set_hex_private_key(&myself->connection->rsa, n, "FFFF", d); + free(n); + free(d); return true; } + /* Else, check for PrivateKeyFile statement and read it */ + if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname)) asprintf(&fname, "%s/rsa_key.priv", confbase); @@ -182,9 +120,10 @@ bool read_rsa_private_key(void) { } #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN) + struct stat s; + if(fstat(fileno(fp), &s)) { - logger(LOG_ERR, _("Could not stat RSA private key file `%s': %s'"), - fname, strerror(errno)); + logger(LOG_ERR, _("Could not stat RSA private key file `%s': %s'"), fname, strerror(errno)); free(fname); return false; } @@ -193,18 +132,13 @@ bool read_rsa_private_key(void) { logger(LOG_WARNING, _("Warning: insecure file permissions for RSA private key file `%s'!"), fname); #endif - myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL); + result = rsa_read_pem_private_key(&myself->connection->rsa, fp); fclose(fp); - if(!myself->connection->rsa_key) { - logger(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"), - fname, strerror(errno)); - free(fname); - return false; - } - + if(!result) + logger(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"), fname, strerror(errno)); free(fname); - return true; + return result; } static struct event keyexpire_event; @@ -214,10 +148,14 @@ static void keyexpire_handler(int fd, short events, void *data) { } void regenerate_key() { - RAND_pseudo_bytes((unsigned char *)myself->key, myself->keylength); + ifdebug(STATUS) logger(LOG_INFO, _("Regenerating symmetric key")); + + if(!cipher_regenerate_key(&myself->cipher, true)) { + logger(LOG_ERR, _("Error regenerating key!")); + abort(); + } if(timeout_initialized(&keyexpire_event)) { - ifdebug(STATUS) logger(LOG_INFO, _("Regenerating symmetric key")); event_del(&keyexpire_event); send_key_changed(broadcast, myself); } else { @@ -225,16 +163,6 @@ void regenerate_key() { } event_add(&keyexpire_event, &(struct timeval){keylifetime, 0}); - - if(myself->cipher) { - EVP_CIPHER_CTX_init(&packet_ctx); - if(!EVP_DecryptInit_ex(&packet_ctx, myself->cipher, NULL, (unsigned char *)myself->key, (unsigned char *)myself->key + myself->cipher->key_len)) { - logger(LOG_ERR, _("Error during initialisation of cipher for %s (%s): %s"), - myself->name, myself->hostname, ERR_error_string(ERR_get_error(), NULL)); - abort(); - } - - } } /* @@ -373,73 +301,44 @@ bool setup_myself(void) { /* Generate packet encryption key */ - if(get_config_string - (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) { - if(!strcasecmp(cipher, "none")) { - myself->cipher = NULL; - } else { - myself->cipher = EVP_get_cipherbyname(cipher); - - if(!myself->cipher) { - logger(LOG_ERR, _("Unrecognized cipher type!")); - return false; - } - } - } else - myself->cipher = EVP_bf_cbc(); - - if(myself->cipher) - myself->keylength = myself->cipher->key_len + myself->cipher->iv_len; - else - myself->keylength = 1; - - myself->connection->outcipher = EVP_bf_ofb(); + if(!get_config_string(lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) + cipher = xstrdup("blowfish"); - myself->key = xmalloc(myself->keylength); + if(!cipher_open_by_name(&myself->cipher, cipher)) { + logger(LOG_ERR, _("Unrecognized cipher type!")); + return false; + } if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime)) keylifetime = 3600; regenerate_key(); + /* Check if we want to use message authentication codes... */ - if(get_config_string - (lookup_config(myself->connection->config_tree, "Digest"), &digest)) { - if(!strcasecmp(digest, "none")) { - myself->digest = NULL; - } else { - myself->digest = EVP_get_digestbyname(digest); - - if(!myself->digest) { - logger(LOG_ERR, _("Unrecognized digest type!")); - return false; - } - } - } else - myself->digest = EVP_sha1(); - - myself->connection->outdigest = EVP_sha1(); - - if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), - &myself->maclength)) { - if(myself->digest) { - if(myself->maclength > myself->digest->md_size) { - logger(LOG_ERR, _("MAC length exceeds size of digest!")); - return false; - } else if(myself->maclength < 0) { - logger(LOG_ERR, _("Bogus MAC length!")); - return false; - } - } - } else - myself->maclength = 4; + if(!get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest)) + digest = xstrdup("sha1"); - myself->connection->outmaclength = 0; + if(!digest_open_by_name(&myself->digest, digest)) { + logger(LOG_ERR, _("Unrecognized digest type!")); + return false; + } + + if(!get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->maclength)) + + if(digest_active(&myself->digest)) { + if(myself->maclength > digest_length(&myself->digest)) { + logger(LOG_ERR, _("MAC length exceeds size of digest!")); + return false; + } else if(myself->maclength < 0) { + logger(LOG_ERR, _("Bogus MAC length!")); + return false; + } + } /* Compression */ - if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), - &myself->compression)) { + if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->compression)) { if(myself->compression < 0 || myself->compression > 11) { logger(LOG_ERR, _("Bogus compression level!")); return false; @@ -463,8 +362,8 @@ bool setup_myself(void) { if(!setup_device()) return false; - event_set(&device_ev, device_fd, EV_READ|EV_PERSIST, - handle_device_data, NULL); + event_set(&device_ev, device_fd, EV_READ|EV_PERSIST, handle_device_data, NULL); + if (event_add(&device_ev, NULL) < 0) { logger(LOG_ERR, _("event_add failed: %s"), strerror(errno)); close_device(); diff --git a/src/node.c b/src/node.c index 0960ca76..99bbb6db 100644 --- a/src/node.c +++ b/src/node.c @@ -74,7 +74,6 @@ node_t *new_node(void) { n->subnet_tree = new_subnet_tree(); n->edge_tree = new_edge_tree(); n->queue = list_alloc((list_action_t) free); - EVP_CIPHER_CTX_init(&n->packet_ctx); n->mtu = MTU; n->maxmtu = MTU; @@ -87,9 +86,6 @@ void free_node(node_t *n) { if(n->queue) list_delete_list(n->queue); - if(n->key) - free(n->key); - if(n->subnet_tree) free_subnet_tree(n->subnet_tree); @@ -98,7 +94,8 @@ void free_node(node_t *n) { sockaddrfree(&n->address); - EVP_CIPHER_CTX_cleanup(&n->packet_ctx); + cipher_close(&n->cipher); + digest_close(&n->digest); event_del(&n->mtuevent); @@ -169,8 +166,8 @@ int dump_nodes(struct evbuffer *out) { for(node = node_tree->head; node; node = node->next) { n = node->data; if(evbuffer_add_printf(out, _(" %s at %s cipher %d digest %d maclength %d compression %d options %lx status %04x nexthop %s via %s pmtu %d (min %d max %d)\n"), - n->name, n->hostname, n->cipher ? n->cipher->nid : 0, - n->digest ? n->digest->type : 0, n->maclength, n->compression, + n->name, n->hostname, cipher_get_nid(&n->cipher), + digest_get_nid(&n->digest), n->maclength, n->compression, n->options, *(uint32_t *)&n->status, n->nexthop ? n->nexthop->name : "-", n->via ? n->via->name : "-", n->mtu, n->minmtu, n->maxmtu) == -1) return errno; diff --git a/src/node.h b/src/node.h index 0476cdb0..fee68593 100644 --- a/src/node.h +++ b/src/node.h @@ -24,7 +24,9 @@ #define __TINC_NODE_H__ #include "splay_tree.h" +#include "cipher.h" #include "connection.h" +#include "digest.h" #include "list.h" #include "subnet.h" @@ -50,13 +52,9 @@ typedef struct node_t { node_status_t status; - const EVP_CIPHER *cipher; /* Cipher type for UDP packets */ - char *key; /* Cipher key and iv */ - int keylength; /* Cipher key and iv length */ - EVP_CIPHER_CTX packet_ctx; /* Cipher context */ - - const EVP_MD *digest; /* Digest type for MAC */ - int maclength; /* Length of MAC */ + cipher_t cipher; /* Cipher for UDP packets */ + digest_t digest; /* Digest for UDP packets */ + int maclength; /* Portion of digest to use */ int compression; /* Compressionlevel, 0 = no compression */ diff --git a/src/protocol_auth.c b/src/protocol_auth.c index 49dfd281..0471932a 100644 --- a/src/protocol_auth.c +++ b/src/protocol_auth.c @@ -22,14 +22,10 @@ #include "system.h" -#include -#include -#include -#include - #include "splay_tree.h" #include "conf.h" #include "connection.h" +#include "crypto.h" #include "edge.h" #include "graph.h" #include "logger.h" @@ -37,6 +33,7 @@ #include "netutl.h" #include "node.h" #include "protocol.h" +#include "rsa.h" #include "utils.h" #include "xalloc.h" @@ -117,27 +114,22 @@ bool id_h(connection_t *c, char *request) { } bool send_metakey(connection_t *c) { - char *buffer; - int len; - bool x; + 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; - if(!c->outkey) - c->outkey = xmalloc(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 @@ -165,135 +158,78 @@ 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 *request) { - char buffer[MAX_STRING_SIZE]; + 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(request, "%*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 */ - - if(!c->inkey) - c->inkey = xmalloc(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 encryption 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 encryption 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; @@ -301,25 +237,17 @@ bool metakey_h(connection_t *c, char *request) { } bool send_challenge(connection_t *c) { - char *buffer; - int len; + 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); - if(!c->hischallenge) c->hischallenge = xmalloc(len); /* Copy random data to the buffer */ - RAND_pseudo_bytes((unsigned char *)c->hischallenge, len); + randomize(c->hischallenge, len); /* Convert to hex */ @@ -333,72 +261,48 @@ bool send_challenge(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(request, "%*d " MAX_STRING, buffer) != 1) { - logger(LOG_ERR, _("Got bad %s from %s (%s)"), "CHALLENGE", c->name, - c->hostname); + 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 */ - - if(!c->mychallenge) - c->mychallenge = xmalloc(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, char *request) { char hishash[MAX_STRING_SIZE]; - char myhash[EVP_MAX_MD_SIZE]; - EVP_MD_CTX ctx; cp(); @@ -410,38 +314,19 @@ bool chal_reply_h(connection_t *c, char *request) { /* 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); - - /* 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 */ + hex2bin(hishash, hishash, digest_length(&c->outdigest)); - 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; } @@ -449,6 +334,8 @@ bool chal_reply_h(connection_t *c, char *request) { Send an acknowledgement with the rest of the information needed. */ + free(c->hischallenge); + c->hischallenge = NULL; c->allow_request = ACK; return send_ack(c); diff --git a/src/protocol_key.c b/src/protocol_key.c index 05bc97ba..52666d99 100644 --- a/src/protocol_key.c +++ b/src/protocol_key.c @@ -22,10 +22,8 @@ #include "system.h" -#include -#include - #include "splay_tree.h" +#include "cipher.h" #include "connection.h" #include "logger.h" #include "net.h" @@ -35,7 +33,7 @@ #include "utils.h" #include "xalloc.h" -bool mykeyused = false; +static bool mykeyused = false; bool send_key_changed(connection_t *c, const node_t *n) { cp(); @@ -137,18 +135,19 @@ bool req_key_h(connection_t *c, char *request) { } bool send_ans_key(connection_t *c, const node_t *from, const node_t *to) { - char *key; + size_t keylen = cipher_keylength(&from->cipher); + char key[keylen * 2 + 1]; cp(); - key = alloca(2 * from->keylength + 1); - bin2hex(from->key, key, from->keylength); - key[from->keylength * 2] = '\0'; + cipher_get_key(&from->cipher, key); + bin2hex(key, key, keylen); + key[keylen * 2] = '\0'; return send_request(c, "%d %s %s %s %d %d %d %d", ANS_KEY, from->name, to->name, key, - from->cipher ? from->cipher->nid : 0, - from->digest ? from->digest->type : 0, from->maclength, + cipher_get_nid(&from->cipher), + digest_get_nid(&from->digest), from->maclength, from->compression); } @@ -194,58 +193,28 @@ bool ans_key_h(connection_t *c, char *request) { return send_request(to->nexthop->connection, "%s", request); } - /* Update our copy of the origin's packet key */ - - if(from->key) - free(from->key); - - from->key = xstrdup(key); - from->keylength = strlen(key) / 2; - hex2bin(from->key, from->key, from->keylength); - from->key[from->keylength] = '\0'; - - from->status.validkey = true; - from->status.waitingforkey = false; - from->sent_seqno = 0; - /* Check and lookup cipher and digest algorithms */ - if(cipher) { - from->cipher = EVP_get_cipherbynid(cipher); - - if(!from->cipher) { - logger(LOG_ERR, _("Node %s (%s) uses unknown cipher!"), from->name, - from->hostname); - return false; - } + if(!cipher_open_by_nid(&from->cipher, cipher)) { + logger(LOG_ERR, _("Node %s (%s) uses unknown cipher!"), from->name, from->hostname); + return false; + } - if(from->keylength != from->cipher->key_len + from->cipher->iv_len) { - logger(LOG_ERR, _("Node %s (%s) uses wrong keylength!"), from->name, - from->hostname); - return false; - } - } else { - from->cipher = NULL; + if(strlen(key) / 2 != cipher_keylength(&from->cipher)) { + logger(LOG_ERR, _("Node %s (%s) uses wrong keylength!"), from->name, from->hostname); + return false; } from->maclength = maclength; - if(digest) { - from->digest = EVP_get_digestbynid(digest); - - if(!from->digest) { - logger(LOG_ERR, _("Node %s (%s) uses unknown digest!"), from->name, - from->hostname); - return false; - } + if(!digest_open_by_nid(&from->digest, digest)) { + logger(LOG_ERR, _("Node %s (%s) uses unknown digest!"), from->name, from->hostname); + return false; + } - if(from->maclength > from->digest->md_size || from->maclength < 0) { - logger(LOG_ERR, _("Node %s (%s) uses bogus MAC length!"), - from->name, from->hostname); - return false; - } - } else { - from->digest = NULL; + if(from->maclength > digest_length(&from->digest) || from->maclength < 0) { + logger(LOG_ERR, _("Node %s (%s) uses bogus MAC length!"), from->name, from->hostname); + return false; } if(compression < 0 || compression > 11) { @@ -255,12 +224,14 @@ bool ans_key_h(connection_t *c, char *request) { from->compression = compression; - if(from->cipher) - if(!EVP_EncryptInit_ex(&from->packet_ctx, from->cipher, NULL, (unsigned char *)from->key, (unsigned char *)from->key + from->cipher->key_len)) { - logger(LOG_ERR, _("Error during initialisation of key from %s (%s): %s"), - from->name, from->hostname, ERR_error_string(ERR_get_error(), NULL)); - return false; - } + /* Update our copy of the origin's packet key */ + + hex2bin(key, key, cipher_keylength(&from->cipher)); + cipher_set_key(&from->cipher, key, false); + + from->status.validkey = true; + from->status.waitingforkey = false; + from->sent_seqno = 0; if(from->options & OPTION_PMTU_DISCOVERY && !from->mtuprobes) send_mtu_probe(from); diff --git a/src/tincd.c b/src/tincd.c index 20443101..0f78e45a 100644 --- a/src/tincd.c +++ b/src/tincd.c @@ -31,18 +31,13 @@ #include #endif -#include -#include -#include -#include -#include - #include LZO1X_H #include #include "conf.h" #include "control.h" +#include "crypto.h" #include "device.h" #include "logger.h" #include "net.h" @@ -295,12 +290,7 @@ int main(int argc, char **argv) /* Slllluuuuuuurrrrp! */ srand(time(NULL)); - RAND_load_file("/dev/urandom", 1024); - - ENGINE_load_builtin_engines(); - ENGINE_register_all_complete(); - - OpenSSL_add_all_algorithms(); + crypto_init(); if(!read_server_config()) return 1; @@ -353,7 +343,7 @@ end: exit_control(); #endif - EVP_cleanup(); - + crypto_exit(); + return status; } -- 2.20.1