From cd5aa5f6f2268a1ad7d11ce8ddbb72362cffbbd4 Mon Sep 17 00:00:00 2001 From: turly221 Date: Sat, 7 Dec 2024 20:24:36 +0000 Subject: [PATCH] commit patch 25345242 --- src/net_packet.c | 3 + src/net_packet.c.orig | 522 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 525 insertions(+) create mode 100644 src/net_packet.c.orig diff --git a/src/net_packet.c b/src/net_packet.c index 20bee349e..713129e57 100644 --- a/src/net_packet.c +++ b/src/net_packet.c @@ -284,6 +284,9 @@ void receive_tcppacket(connection_t *c, char *buffer, int len) cp(); + if(len > sizeof outpkt.data) + return; + outpkt.len = len; memcpy(outpkt.data, buffer, len); diff --git a/src/net_packet.c.orig b/src/net_packet.c.orig new file mode 100644 index 000000000..20bee349e --- /dev/null +++ b/src/net_packet.c.orig @@ -0,0 +1,522 @@ +/* + net_packet.c -- Handles in- and outgoing VPN packets + Copyright (C) 1998-2005 Ivo Timmermans, + 2000-2006 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 + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + $Id$ +*/ + +#include "system.h" + +#include +#include +#include +#include +#include + +#include +#ifdef HAVE_LZO_LZO1X_H +#include +#endif +#ifdef HAVE_LZO1X_H +#include +#endif + +#include "avl_tree.h" +#include "conf.h" +#include "connection.h" +#include "device.h" +#include "ethernet.h" +#include "event.h" +#include "graph.h" +#include "list.h" +#include "logger.h" +#include "net.h" +#include "netutl.h" +#include "protocol.h" +#include "process.h" +#include "route.h" +#include "utils.h" +#include "xalloc.h" + +#ifdef WSAEMSGSIZE +#define EMSGSIZE WSAEMSGSIZE +#endif + +int keylifetime = 0; +int keyexpires = 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 *); + +#define MAX_SEQNO 1073741824 + +void send_mtu_probe(node_t *n) +{ + vpn_packet_t packet; + int len, i; + + cp(); + + n->mtuprobes++; + n->mtuevent = NULL; + + if(n->mtuprobes >= 10 && !n->minmtu) { + ifdebug(TRAFFIC) logger(LOG_INFO, _("No response to MTU probes from %s (%s)"), n->name, n->hostname); + return; + } + + for(i = 0; i < 3; i++) { + if(n->mtuprobes >= 30 || n->minmtu >= n->maxmtu) { + n->mtu = n->minmtu; + ifdebug(TRAFFIC) logger(LOG_INFO, _("Fixing MTU of %s (%s) to %d after %d probes"), n->name, n->hostname, n->mtu, n->mtuprobes); + return; + } + + len = n->minmtu + 1 + random() % (n->maxmtu - n->minmtu); + if(len < 64) + len = 64; + + memset(packet.data, 0, 14); + RAND_pseudo_bytes(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); + + send_udppacket(n, &packet); + } + + n->mtuevent = new_event(); + n->mtuevent->handler = (event_handler_t)send_mtu_probe; + n->mtuevent->data = n; + n->mtuevent->time = now + 1; + event_add(n->mtuevent); +} + +void mtu_probe_h(node_t *n, vpn_packet_t *packet) { + ifdebug(TRAFFIC) logger(LOG_INFO, _("Got MTU probe length %d from %s (%s)"), packet->len, n->name, n->hostname); + + if(!packet->data[0]) { + packet->data[0] = 1; + send_packet(n, packet); + } else { + if(n->minmtu < packet->len) + n->minmtu = packet->len; + } +} + +static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) +{ + if(level == 10) { + lzo_uint lzolen = MAXSIZE; + lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem); + return lzolen; + } else if(level < 10) { + unsigned long destlen = MAXSIZE; + if(compress2(dest, &destlen, source, len, level) == Z_OK) + return destlen; + else + return -1; + } else { + lzo_uint lzolen = MAXSIZE; + lzo1x_999_compress(source, len, dest, &lzolen, lzo_wrkmem); + return lzolen; + } + + return -1; +} + +static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) +{ + if(level > 9) { + lzo_uint lzolen = MAXSIZE; + if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK) + return lzolen; + else + return -1; + } else { + unsigned long destlen = MAXSIZE; + if(uncompress(dest, &destlen, source, len) == Z_OK) + return destlen; + else + return -1; + } + + return -1; +} + +/* VPN packet I/O */ + +static void receive_packet(node_t *n, vpn_packet_t *packet) +{ + cp(); + + ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Received packet of %d bytes from %s (%s)"), + packet->len, n->name, n->hostname); + + route(n, packet); +} + +static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) +{ + vpn_packet_t pkt1, pkt2; + 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]; + int i; + + cp(); + + /* Check packet length */ + + if(inpkt->len < sizeof(inpkt->seqno) + myself->maclength) { + ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got too short packet from %s (%s)"), + n->name, n->hostname); + return; + } + + /* 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; + } + } + + /* Decrypt the packet */ + + if(myself->cipher) { + outpkt = pkt[nextpkt++]; + + 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)); + return; + } + + outpkt->len = outlen + outpad; + inpkt = outpkt; + } + + /* Check the sequence number */ + + inpkt->len -= sizeof(inpkt->seqno); + inpkt->seqno = ntohl(inpkt->seqno); + + if(inpkt->seqno != n->received_seqno + 1) { + if(inpkt->seqno >= n->received_seqno + sizeof(n->late) * 8) { + logger(LOG_WARNING, _("Lost %d packets from %s (%s)"), + inpkt->seqno - n->received_seqno - 1, n->name, n->hostname); + + memset(n->late, 0, sizeof(n->late)); + } else if (inpkt->seqno <= n->received_seqno) { + if((n->received_seqno >= sizeof(n->late) * 8 && inpkt->seqno <= n->received_seqno - sizeof(n->late) * 8) || !(n->late[(inpkt->seqno / 8) % sizeof(n->late)] & (1 << inpkt->seqno % 8))) { + logger(LOG_WARNING, _("Got late or replayed packet from %s (%s), seqno %d, last received %d"), + n->name, n->hostname, inpkt->seqno, n->received_seqno); + return; + } + } else { + for(i = n->received_seqno + 1; i < inpkt->seqno; i++) + n->late[(i / 8) % sizeof(n->late)] |= 1 << i % 8; + } + } + + n->late[(inpkt->seqno / 8) % sizeof(n->late)] &= ~(1 << inpkt->seqno % 8); + + if(inpkt->seqno > n->received_seqno) + n->received_seqno = inpkt->seqno; + + if(n->received_seqno > MAX_SEQNO) + keyexpires = 0; + + /* Decompress the packet */ + + if(myself->compression) { + outpkt = pkt[nextpkt++]; + + if((outpkt->len = uncompress_packet(outpkt->data, inpkt->data, inpkt->len, myself->compression)) < 0) { + ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while uncompressing packet from %s (%s)"), + n->name, n->hostname); + return; + } + + inpkt = outpkt; + } + + if(n->connection) + n->connection->last_ping_time = now; + + if(!inpkt->data[12] && !inpkt->data[13]) + mtu_probe_h(n, inpkt); + else + receive_packet(n, inpkt); +} + +void receive_tcppacket(connection_t *c, char *buffer, int len) +{ + vpn_packet_t outpkt; + + cp(); + + outpkt.len = len; + memcpy(outpkt.data, buffer, len); + + receive_packet(c->node, &outpkt); +} + +static void send_udppacket(node_t *n, vpn_packet_t *origpkt) +{ + vpn_packet_t pkt1, pkt2; + vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 }; + vpn_packet_t *inpkt = origpkt; + int nextpkt = 0; + vpn_packet_t *outpkt; + int origlen; + int outlen, outpad; + vpn_packet_t *copy; + static int priority = 0; + int origpriority; + int sock; + + cp(); + + /* Make sure we have a valid key */ + + if(!n->status.validkey) { + ifdebug(TRAFFIC) logger(LOG_INFO, + _("No valid key known yet for %s (%s), queueing packet"), + n->name, n->hostname); + + /* Since packet is on the stack of handle_tap_input(), we have to make a copy of it first. */ + + *(copy = xmalloc(sizeof(*copy))) = *inpkt; + + list_insert_tail(n->queue, copy); + + if(n->queue->count > MAXQUEUELENGTH) + list_delete_head(n->queue); + + if(!n->status.waitingforkey) + send_req_key(n->nexthop->connection, myself, n); + + n->status.waitingforkey = true; + + return; + } + + origlen = inpkt->len; + origpriority = inpkt->priority; + + /* Compress the packet */ + + if(n->compression) { + outpkt = pkt[nextpkt++]; + + if((outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->compression)) < 0) { + ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while compressing packet to %s (%s)"), + n->name, n->hostname); + return; + } + + inpkt = outpkt; + } + + /* Add sequence number */ + + inpkt->seqno = htonl(++(n->sent_seqno)); + inpkt->len += sizeof(inpkt->seqno); + + /* Encrypt the packet */ + + if(n->cipher) { + outpkt = pkt[nextpkt++]; + + 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)); + goto end; + } + + outpkt->len = outlen + outpad; + 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; + } + + /* Determine which socket we have to use */ + + for(sock = 0; sock < listen_sockets; sock++) + if(n->address.sa.sa_family == listen_socket[sock].sa.sa.sa_family) + break; + + if(sock >= listen_sockets) + sock = 0; /* If none is available, just use the first and hope for the best. */ + + /* Send the packet */ + +#if defined(SOL_IP) && defined(IP_TOS) + if(priorityinheritance && origpriority != priority + && listen_socket[sock].sa.sa.sa_family == AF_INET) { + priority = origpriority; + ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Setting outgoing packet priority to %d"), priority); + if(setsockopt(listen_socket[sock].udp, SOL_IP, IP_TOS, &priority, sizeof(priority))) /* SO_PRIORITY doesn't seem to work */ + logger(LOG_ERR, _("System call `%s' failed: %s"), "setsockopt", strerror(errno)); + } +#endif + + if((sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa))) < 0) { + if(errno == EMSGSIZE) { + if(n->maxmtu >= origlen) + n->maxmtu = origlen - 1; + if(n->mtu >= origlen) + n->mtu = origlen - 1; + } else + logger(LOG_ERR, _("Error sending packet to %s (%s): %s"), n->name, n->hostname, strerror(errno)); + } + +end: + origpkt->len = origlen; +} + +/* + send a packet to the given vpn ip. +*/ +void send_packet(const node_t *n, vpn_packet_t *packet) +{ + node_t *via; + + cp(); + + if(n == myself) { + if(overwrite_mac) + memcpy(packet->data, mymac.x, ETH_ALEN); + write_packet(packet); + return; + } + + ifdebug(TRAFFIC) logger(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"), + packet->len, n->name, n->hostname); + + if(!n->status.reachable) { + ifdebug(TRAFFIC) logger(LOG_INFO, _("Node %s (%s) is not reachable"), + n->name, n->hostname); + return; + } + + via = (n->via == myself) ? n->nexthop : n->via; + + if(via != n) + ifdebug(TRAFFIC) logger(LOG_ERR, _("Sending packet to %s via %s (%s)"), + n->name, via->name, n->via->hostname); + + if((myself->options | via->options) & OPTION_TCPONLY) { + if(!send_tcppacket(via->connection, packet)) + terminate_connection(via->connection, true); + } else + send_udppacket(via, packet); +} + +/* Broadcast a packet using the minimum spanning tree */ + +void broadcast_packet(const node_t *from, vpn_packet_t *packet) +{ + avl_node_t *node; + connection_t *c; + + cp(); + + ifdebug(TRAFFIC) logger(LOG_INFO, _("Broadcasting packet of %d bytes from %s (%s)"), + packet->len, from->name, from->hostname); + + if(from != myself) + send_packet(myself, packet); + + for(node = connection_tree->head; node; node = node->next) { + c = node->data; + + if(c->status.active && c->status.mst && c != from->nexthop->connection) + send_packet(c->node, packet); + } +} + +void flush_queue(node_t *n) +{ + list_node_t *node, *next; + + cp(); + + ifdebug(TRAFFIC) logger(LOG_INFO, _("Flushing queue for %s (%s)"), n->name, n->hostname); + + for(node = n->queue->head; node; node = next) { + next = node->next; + send_udppacket(n, node->data); + list_delete_node(n->queue, node); + } +} + +void handle_incoming_vpn_data(int sock) +{ + vpn_packet_t pkt; + char *hostname; + sockaddr_t from; + socklen_t fromlen = sizeof(from); + node_t *n; + + cp(); + + pkt.len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen); + + if(pkt.len < 0) { + logger(LOG_ERR, _("Receiving packet failed: %s"), strerror(errno)); + return; + } + + sockaddrunmap(&from); /* Some braindead IPv6 implementations do stupid things. */ + + n = lookup_node_udp(&from); + + if(!n) { + hostname = sockaddr2hostname(&from); + logger(LOG_WARNING, _("Received UDP packet from unknown source %s"), + hostname); + free(hostname); + return; + } + + receive_udppacket(n, &pkt); +}