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-rw-r--r--src/charon/network/socket.c456
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diff --git a/src/charon/network/socket.c b/src/charon/network/socket.c
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+/**
+ * @file socket.c
+ *
+ * @brief Implementation of socket_t.
+ *
+ */
+
+/*
+ * Copyright (C) 2005 Jan Hutter, Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ * Copyright (C) 1998-2002 D. Hugh Redelmeier.
+ * Copyright (C) 1997 Angelos D. Keromytis.
+ *
+ * Some parts of interface lookup code from pluto.
+ *
+ * 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. See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+#include <pthread.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
+#include <netinet/in.h>
+#include <linux/filter.h>
+
+#include "socket.h"
+
+#include <daemon.h>
+#include <utils/logger_manager.h>
+
+
+#define IP_HEADER_LENGTH 20
+#define UDP_HEADER_LENGTH 8
+
+
+/**
+ * This filter code filters out all non-IKEv2 traffic on
+ * a SOCK_RAW IP_PROTP_UDP socket. Handling of other
+ * IKE versions is done in pluto.
+ */
+struct sock_filter ikev2_filter_code[] =
+{
+ /* Protocol must be UDP */
+ BPF_STMT(BPF_LD+BPF_B+BPF_ABS, 9),
+ BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, IPPROTO_UDP, 0, 7),
+ /* Destination Port must be 500 */
+ BPF_STMT(BPF_LD+BPF_H+BPF_ABS, 22),
+ BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, 500, 0, 5),
+ /* IKE version must be 2.0 */
+ BPF_STMT(BPF_LD+BPF_B+BPF_ABS, 45),
+ BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, 0x20, 0, 3),
+ /* packet length is length in IKEv2 header + ip header + udp header */
+ BPF_STMT(BPF_LD+BPF_W+BPF_ABS, 52),
+ BPF_STMT(BPF_ALU+BPF_ADD+BPF_K, IP_HEADER_LENGTH + UDP_HEADER_LENGTH),
+ BPF_STMT(BPF_RET+BPF_A, 0),
+ /* packet doesn't match IKEv2, ignore */
+ BPF_STMT(BPF_RET+BPF_K, 0),
+};
+
+/**
+ * Filter struct to use with setsockopt
+ */
+struct sock_fprog ikev2_filter = {
+ sizeof(ikev2_filter_code) / sizeof(struct sock_filter),
+ ikev2_filter_code
+};
+
+
+typedef struct interface_t interface_t;
+
+/**
+ * An interface on which we listen.
+ */
+struct interface_t {
+
+ /**
+ * Name of the interface
+ */
+ char name[IFNAMSIZ];
+
+ /**
+ * Associated socket
+ */
+ int socket_fd;
+
+ /**
+ * Host with listening address
+ */
+ host_t *address;
+};
+
+typedef struct private_socket_t private_socket_t;
+
+/**
+ * Private data of an socket_t object
+ */
+struct private_socket_t{
+ /**
+ * public functions
+ */
+ socket_t public;
+
+ /**
+ * Master socket
+ */
+ int master_fd;
+
+ /**
+ * List of all socket to listen
+ */
+ linked_list_t* interfaces;
+
+ /**
+ * logger for this socket
+ */
+ logger_t *logger;
+};
+
+/**
+ * implementation of socket_t.receive
+ */
+static status_t receiver(private_socket_t *this, packet_t **packet)
+{
+ char buffer[MAX_PACKET];
+ chunk_t data;
+ packet_t *pkt = packet_create();
+ host_t *source, *dest;
+ int bytes_read = 0;
+
+
+ while (bytes_read >= 0)
+ {
+ int max_fd = 1;
+ fd_set readfds;
+ iterator_t *iterator;
+ int oldstate;
+ interface_t *interface;
+
+ /* build fd_set */
+ FD_ZERO(&readfds);
+ iterator = this->interfaces->create_iterator(this->interfaces, TRUE);
+ while (iterator->has_next(iterator))
+ {
+ iterator->current(iterator, (void**)&interface);
+ FD_SET(interface->socket_fd, &readfds);
+ if (interface->socket_fd > max_fd)
+ {
+ max_fd = interface->socket_fd + 1;
+ }
+ }
+ iterator->destroy(iterator);
+
+ /* add packet destroy handler for cancellation, enable cancellation */
+ pthread_cleanup_push((void(*)(void*))pkt->destroy, (void*)pkt);
+ pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldstate);
+
+ this->logger->log(this->logger, CONTROL|LEVEL1, "waiting on sockets");
+ bytes_read = select(max_fd, &readfds, NULL, NULL, NULL);
+
+ /* reset cancellation, remove packet destroy handler (without executing) */
+ pthread_setcancelstate(oldstate, NULL);
+ pthread_cleanup_pop(0);
+
+ /* read on the first nonblocking socket */
+ bytes_read = 0;
+ iterator = this->interfaces->create_iterator(this->interfaces, TRUE);
+ while (iterator->has_next(iterator))
+ {
+ iterator->current(iterator, (void**)&interface);
+ if (FD_ISSET(interface->socket_fd, &readfds))
+ {
+ /* do the read */
+ bytes_read = recv(interface->socket_fd, buffer, MAX_PACKET, 0);
+ break;
+ }
+ }
+ iterator->destroy(iterator);
+
+ if (bytes_read < 0)
+ {
+ this->logger->log(this->logger, ERROR, "error reading from socket: %s", strerror(errno));
+ continue;
+ }
+ if (bytes_read > IP_HEADER_LENGTH + UDP_HEADER_LENGTH)
+ {
+ /* read source/dest from raw IP/UDP header */
+ chunk_t source_chunk = {buffer + 12, 4};
+ chunk_t dest_chunk = {buffer + 16, 4};
+ u_int16_t source_port = ntohs(*(u_int16_t*)(buffer + 20));
+ u_int16_t dest_port = ntohs(*(u_int16_t*)(buffer + 22));
+ source = host_create_from_chunk(AF_INET, source_chunk, source_port);
+ dest = host_create_from_chunk(AF_INET, dest_chunk, dest_port);
+ pkt->set_source(pkt, source);
+ pkt->set_destination(pkt, dest);
+ break;
+ }
+ this->logger->log(this->logger, ERROR|LEVEL1, "too short packet received");
+ }
+
+ this->logger->log(this->logger, CONTROL, "received packet: from %s:%d to %s:%d",
+ source->get_address(source), source->get_port(source),
+ dest->get_address(dest), dest->get_port(dest));
+
+ /* fill in packet */
+ data.len = bytes_read - IP_HEADER_LENGTH - UDP_HEADER_LENGTH;
+ data.ptr = malloc(data.len);
+ memcpy(data.ptr, buffer + IP_HEADER_LENGTH + UDP_HEADER_LENGTH, data.len);
+ pkt->set_data(pkt, data);
+
+ /* return packet */
+ *packet = pkt;
+
+ return SUCCESS;
+}
+
+/**
+ * implementation of socket_t.send
+ */
+status_t sender(private_socket_t *this, packet_t *packet)
+{
+ ssize_t bytes_sent;
+ chunk_t data;
+ host_t *src, *dst;
+
+ src = packet->get_source(packet);
+ dst = packet->get_destination(packet);
+ data = packet->get_data(packet);
+
+ this->logger->log(this->logger, CONTROL, "sending packet: from %s:%d to %s:%d",
+ src->get_address(src), src->get_port(src),
+ dst->get_address(dst), dst->get_port(dst));
+
+ /* send data */
+ /* TODO: should we send via the interface we received the packet? */
+ bytes_sent = sendto(this->master_fd, data.ptr, data.len, 0,
+ dst->get_sockaddr(dst), *(dst->get_sockaddr_len(dst)));
+
+ if (bytes_sent != data.len)
+ {
+ this->logger->log(this->logger, ERROR, "error writing to socket: %s", strerror(errno));
+ return FAILED;
+ }
+ return SUCCESS;
+}
+
+/**
+ * Find all suitable interfaces, bind them and add them to the list
+ */
+static status_t build_interface_list(private_socket_t *this, u_int16_t port)
+{
+ int on = TRUE;
+ int i;
+ struct sockaddr_in addr;
+ struct ifconf ifconf;
+ struct ifreq buf[300];
+
+ /* master socket for querying socket for a specific interfaces */
+ this->master_fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+ if (this->master_fd == -1)
+ {
+ this->logger->log(this->logger, ERROR, "could not open IPv4 master socket!");
+ return FAILED;
+ }
+
+ /* allow binding of multiplo sockets */
+ if (setsockopt(this->master_fd, SOL_SOCKET, SO_REUSEADDR, (void*)&on, sizeof(on)) < 0)
+ {
+ this->logger->log(this->logger, ERROR, "unable to set SO_REUSEADDR on master socket!");
+ return FAILED;
+ }
+
+ /* bind the master socket */
+ addr.sin_family = AF_INET;
+ addr.sin_addr.s_addr = INADDR_ANY;
+ addr.sin_port = htons(port);
+ if (bind(this->master_fd,(struct sockaddr*)&addr, sizeof(addr)) < 0)
+ {
+ this->logger->log(this->logger, ERROR, "unable to bind master socket: %s!", strerror(errno));
+ return FAILED;
+ }
+
+ /* get all interfaces */
+ ifconf.ifc_len = sizeof(buf);
+ ifconf.ifc_buf = (void*) buf;
+ memset(buf, 0, sizeof(buf));
+ if (ioctl(this->master_fd, SIOCGIFCONF, &ifconf) == -1)
+ {
+ this->logger->log(this->logger, ERROR, "unable to get interfaces!");
+ return FAILED;
+ }
+
+ /* add every interesting interfaces to our interface list */
+ for (i = 0; (i+1) * sizeof(*buf) <= (size_t)ifconf.ifc_len; i++)
+ {
+ struct sockaddr_in *current = (struct sockaddr_in*) &buf[i].ifr_addr;
+ struct ifreq auxinfo;
+ int skt;
+ interface_t *interface;
+
+ if (current->sin_family != AF_INET)
+ {
+ /* ignore all but AF_INET interfaces */
+ continue;
+ }
+
+ /* get auxilary info about socket */
+ memset(&auxinfo, 0, sizeof(auxinfo));
+ memcpy(auxinfo.ifr_name, buf[i].ifr_name, IFNAMSIZ);
+ if (ioctl(this->master_fd, SIOCGIFFLAGS, &auxinfo) == -1)
+ {
+ this->logger->log(this->logger, ERROR, "unable to SIOCGIFFLAGS master socket!");
+ continue;
+ }
+ if (!(auxinfo.ifr_flags & IFF_UP))
+ {
+ /* ignore an interface that isn't up */
+ continue;
+ }
+ if (current->sin_addr.s_addr == 0)
+ {
+ /* ignore unconfigured interfaces */
+ continue;
+ }
+
+ /* set up interface socket */
+ skt = socket(AF_INET, SOCK_RAW, IPPROTO_UDP);
+ if (socket < 0)
+ {
+ this->logger->log(this->logger, ERROR, "unable to open interface socket!");
+ continue;
+ }
+ if (setsockopt(skt, SOL_SOCKET, SO_REUSEADDR, (void*)&on, sizeof(on)) < 0)
+ {
+ this->logger->log(this->logger, ERROR, "unable to set SO_REUSEADDR on interface socket!");
+ close(skt);
+ continue;
+ }
+ current->sin_port = htons(port);
+ current->sin_family = AF_INET;
+ if (bind(skt, (struct sockaddr*)current, sizeof(struct sockaddr_in)) < 0)
+ {
+ this->logger->log(this->logger, ERROR, "unable to bind interface socket!");
+ close(skt);
+ continue;
+ }
+
+ if (setsockopt(skt, SOL_SOCKET, SO_ATTACH_FILTER, &ikev2_filter, sizeof(ikev2_filter)) < 0)
+ {
+ this->logger->log(this->logger, ERROR, "unable to attack IKEv2 filter to interface socket!");
+ close(skt);
+ continue;
+ }
+
+ /* add socket with interface name to list */
+ interface = malloc_thing(interface_t);
+ strncpy(interface->name, buf[i].ifr_name, IFNAMSIZ);
+ interface->socket_fd = skt;
+ interface->address = host_create_from_sockaddr((struct sockaddr*)current);
+ this->logger->log(this->logger, CONTROL, "listening on %s (%s)",
+ interface->name, interface->address->get_address(interface->address));
+ this->interfaces->insert_last(this->interfaces, (void*)interface);
+ }
+
+ if (this->interfaces->get_count(this->interfaces) == 0)
+ {
+ this->logger->log(this->logger, ERROR, "unable to find any usable interface!");
+ return FAILED;
+ }
+ return SUCCESS;
+}
+
+/**
+ * implementation of socket_t.is_listening_on
+ */
+static bool is_listening_on(private_socket_t *this, host_t *host)
+{
+ iterator_t *iterator;
+
+ /* listening on 0.0.0.0 is always TRUE */
+ if (host->is_default_route(host))
+ {
+ return TRUE;
+ }
+
+ /* compare host with all interfaces */
+ iterator = this->interfaces->create_iterator(this->interfaces, TRUE);
+ while (iterator->has_next(iterator))
+ {
+ interface_t *interface;
+ iterator->current(iterator, (void**)&interface);
+ if (host->equals(host, interface->address))
+ {
+ iterator->destroy(iterator);
+ return TRUE;
+ }
+ }
+ iterator->destroy(iterator);
+ return FALSE;
+}
+
+/**
+ * implementation of socket_t.destroy
+ */
+static void destroy(private_socket_t *this)
+{
+ interface_t *interface;
+ while (this->interfaces->remove_last(this->interfaces, (void**)&interface) == SUCCESS)
+ {
+ interface->address->destroy(interface->address);
+ close(interface->socket_fd);
+ free(interface);
+ }
+ this->interfaces->destroy(this->interfaces);
+ close(this->master_fd);
+ free(this);
+}
+
+/*
+ * See header for description
+ */
+socket_t *socket_create(u_int16_t port)
+{
+ private_socket_t *this = malloc_thing(private_socket_t);
+
+ /* public functions */
+ this->public.send = (status_t(*)(socket_t*, packet_t*))sender;
+ this->public.receive = (status_t(*)(socket_t*, packet_t**))receiver;
+ this->public.is_listening_on = (bool (*)(socket_t*,host_t*))is_listening_on;
+ this->public.destroy = (void(*)(socket_t*)) destroy;
+
+ this->logger = logger_manager->get_logger(logger_manager, SOCKET);
+ this->interfaces = linked_list_create();
+
+ if (build_interface_list(this, port) != SUCCESS)
+ {
+ this->interfaces->destroy(this->interfaces);
+ free(this);
+ charon->kill(charon, "could not bind any interface!");
+ }
+
+ return (socket_t*)this;
+}
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