diff options
Diffstat (limited to 'src/libhydra/plugins/kernel_pfroute/kernel_pfroute_net.c')
| -rw-r--r-- | src/libhydra/plugins/kernel_pfroute/kernel_pfroute_net.c | 742 |
1 files changed, 742 insertions, 0 deletions
diff --git a/src/libhydra/plugins/kernel_pfroute/kernel_pfroute_net.c b/src/libhydra/plugins/kernel_pfroute/kernel_pfroute_net.c new file mode 100644 index 000000000..99b99a274 --- /dev/null +++ b/src/libhydra/plugins/kernel_pfroute/kernel_pfroute_net.c @@ -0,0 +1,742 @@ +/* + * Copyright (C) 2009 Tobias Brunner + * Hochschule fuer Technik Rapperswil + * + * 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 <sys/types.h> +#include <sys/socket.h> +#include <net/if.h> +#include <ifaddrs.h> +#include <net/route.h> +#include <unistd.h> +#include <errno.h> + +#include "kernel_pfroute_net.h" + +#include <hydra.h> +#include <debug.h> +#include <utils/host.h> +#include <threading/thread.h> +#include <threading/mutex.h> +#include <utils/linked_list.h> +#include <processing/jobs/callback_job.h> + +#ifndef HAVE_STRUCT_SOCKADDR_SA_LEN +#error Cannot compile this plugin on systems where 'struct sockaddr' has no sa_len member. +#endif + +/** delay before firing roam events (ms) */ +#define ROAM_DELAY 100 + +/** buffer size for PF_ROUTE messages */ +#define PFROUTE_BUFFER_SIZE 4096 + +typedef struct addr_entry_t addr_entry_t; + +/** + * IP address in an inface_entry_t + */ +struct addr_entry_t { + + /** The ip address */ + host_t *ip; + + /** virtual IP managed by us */ + bool virtual; + + /** Number of times this IP is used, if virtual */ + u_int refcount; +}; + +/** + * destroy a addr_entry_t object + */ +static void addr_entry_destroy(addr_entry_t *this) +{ + this->ip->destroy(this->ip); + free(this); +} + +typedef struct iface_entry_t iface_entry_t; + +/** + * A network interface on this system, containing addr_entry_t's + */ +struct iface_entry_t { + + /** interface index */ + int ifindex; + + /** name of the interface */ + char ifname[IFNAMSIZ]; + + /** interface flags, as in netdevice(7) SIOCGIFFLAGS */ + u_int flags; + + /** list of addresses as host_t */ + linked_list_t *addrs; +}; + +/** + * destroy an interface entry + */ +static void iface_entry_destroy(iface_entry_t *this) +{ + this->addrs->destroy_function(this->addrs, (void*)addr_entry_destroy); + free(this); +} + + +typedef struct private_kernel_pfroute_net_t private_kernel_pfroute_net_t; + +/** + * Private variables and functions of kernel_pfroute class. + */ +struct private_kernel_pfroute_net_t +{ + /** + * Public part of the kernel_pfroute_t object. + */ + kernel_pfroute_net_t public; + + /** + * mutex to lock access to various lists + */ + mutex_t *mutex; + + /** + * Cached list of interfaces and their addresses (iface_entry_t) + */ + linked_list_t *ifaces; + + /** + * job receiving PF_ROUTE events + */ + callback_job_t *job; + + /** + * mutex to lock access to the PF_ROUTE socket + */ + mutex_t *mutex_pfroute; + + /** + * PF_ROUTE socket to communicate with the kernel + */ + int socket; + + /** + * PF_ROUTE socket to receive events + */ + int socket_events; + + /** + * sequence number for messages sent to the kernel + */ + int seq; + + /** + * time of last roam event + */ + timeval_t last_roam; +}; + +/** + * callback function that raises the delayed roam event + */ +static job_requeue_t roam_event(uintptr_t address) +{ + hydra->kernel_interface->roam(hydra->kernel_interface, address != 0); + return JOB_REQUEUE_NONE; +} + +/** + * fire a roaming event. we delay it for a bit and fire only one event + * for multiple calls. otherwise we would create too many events. + */ +static void fire_roam_event(private_kernel_pfroute_net_t *this, bool address) +{ + timeval_t now; + job_t *job; + + time_monotonic(&now); + if (timercmp(&now, &this->last_roam, >)) + { + now.tv_usec += ROAM_DELAY * 1000; + while (now.tv_usec > 1000000) + { + now.tv_sec++; + now.tv_usec -= 1000000; + } + this->last_roam = now; + + job = (job_t*)callback_job_create((callback_job_cb_t)roam_event, + (void*)(uintptr_t)(address ? 1 : 0), + NULL, NULL); + hydra->scheduler->schedule_job_ms(hydra->scheduler, job, ROAM_DELAY); + } +} + +/** + * Process an RTM_*ADDR message from the kernel + */ +static void process_addr(private_kernel_pfroute_net_t *this, + struct rt_msghdr *msg) +{ + struct ifa_msghdr *ifa = (struct ifa_msghdr*)msg; + sockaddr_t *sockaddr = (sockaddr_t*)(ifa + 1); + host_t *host = NULL; + enumerator_t *ifaces, *addrs; + iface_entry_t *iface; + addr_entry_t *addr; + bool found = FALSE, changed = FALSE, roam = FALSE; + int i; + + for (i = 1; i < (1 << RTAX_MAX); i <<= 1) + { + if (ifa->ifam_addrs & i) + { + if (RTA_IFA & i) + { + host = host_create_from_sockaddr(sockaddr); + break; + } + sockaddr = (sockaddr_t*)((char*)sockaddr + sockaddr->sa_len); + } + } + + if (!host) + { + return; + } + + this->mutex->lock(this->mutex); + ifaces = this->ifaces->create_enumerator(this->ifaces); + while (ifaces->enumerate(ifaces, &iface)) + { + if (iface->ifindex == ifa->ifam_index) + { + addrs = iface->addrs->create_enumerator(iface->addrs); + while (addrs->enumerate(addrs, &addr)) + { + if (host->ip_equals(host, addr->ip)) + { + found = TRUE; + if (ifa->ifam_type == RTM_DELADDR) + { + iface->addrs->remove_at(iface->addrs, addrs); + if (!addr->virtual) + { + changed = TRUE; + DBG1(DBG_KNL, "%H disappeared from %s", + host, iface->ifname); + } + addr_entry_destroy(addr); + } + else if (ifa->ifam_type == RTM_NEWADDR && addr->virtual) + { + addr->refcount = 1; + } + } + } + addrs->destroy(addrs); + + if (!found && ifa->ifam_type == RTM_NEWADDR) + { + changed = TRUE; + addr = malloc_thing(addr_entry_t); + addr->ip = host->clone(host); + addr->virtual = FALSE; + addr->refcount = 1; + iface->addrs->insert_last(iface->addrs, addr); + DBG1(DBG_KNL, "%H appeared on %s", host, iface->ifname); + } + + if (changed && (iface->flags & IFF_UP)) + { + roam = TRUE; + } + break; + } + } + ifaces->destroy(ifaces); + this->mutex->unlock(this->mutex); + host->destroy(host); + + if (roam) + { + fire_roam_event(this, TRUE); + } +} + +/** + * Process an RTM_IFINFO message from the kernel + */ +static void process_link(private_kernel_pfroute_net_t *this, + struct rt_msghdr *hdr) +{ + struct if_msghdr *msg = (struct if_msghdr*)hdr; + enumerator_t *enumerator; + iface_entry_t *iface; + bool roam = FALSE; + + if (msg->ifm_flags & IFF_LOOPBACK) + { /* ignore loopback interfaces */ + return; + } + + this->mutex->lock(this->mutex); + enumerator = this->ifaces->create_enumerator(this->ifaces); + while (enumerator->enumerate(enumerator, &iface)) + { + if (iface->ifindex == msg->ifm_index) + { + if (!(iface->flags & IFF_UP) && (msg->ifm_flags & IFF_UP)) + { + roam = TRUE; + DBG1(DBG_KNL, "interface %s activated", iface->ifname); + } + else if ((iface->flags & IFF_UP) && !(msg->ifm_flags & IFF_UP)) + { + roam = TRUE; + DBG1(DBG_KNL, "interface %s deactivated", iface->ifname); + } + iface->flags = msg->ifm_flags; + break; + } + } + enumerator->destroy(enumerator); + this->mutex->unlock(this->mutex); + + if (roam) + { + fire_roam_event(this, TRUE); + } +} + +/** + * Process an RTM_*ROUTE message from the kernel + */ +static void process_route(private_kernel_pfroute_net_t *this, + struct rt_msghdr *msg) +{ + +} + +/** + * Receives events from kernel + */ +static job_requeue_t receive_events(private_kernel_pfroute_net_t *this) +{ + unsigned char buf[PFROUTE_BUFFER_SIZE]; + struct rt_msghdr *msg = (struct rt_msghdr*)buf; + int len; + bool oldstate; + + oldstate = thread_cancelability(TRUE); + len = recvfrom(this->socket_events, buf, sizeof(buf), 0, NULL, 0); + thread_cancelability(oldstate); + + if (len < 0) + { + switch (errno) + { + case EINTR: + /* interrupted, try again */ + return JOB_REQUEUE_DIRECT; + case EAGAIN: + /* no data ready, select again */ + return JOB_REQUEUE_DIRECT; + default: + DBG1(DBG_KNL, "unable to receive from PF_ROUTE event socket"); + sleep(1); + return JOB_REQUEUE_FAIR; + } + } + + if (len < sizeof(msg->rtm_msglen) || len < msg->rtm_msglen || + msg->rtm_version != RTM_VERSION) + { + DBG2(DBG_KNL, "received corrupted PF_ROUTE message"); + return JOB_REQUEUE_DIRECT; + } + + switch (msg->rtm_type) + { + case RTM_NEWADDR: + case RTM_DELADDR: + process_addr(this, msg); + break; + case RTM_IFINFO: + /*case RTM_IFANNOUNCE <- what about this*/ + process_link(this, msg); + break; + case RTM_ADD: + case RTM_DELETE: + process_route(this, msg); + default: + break; + } + + return JOB_REQUEUE_DIRECT; +} + + +/** enumerator over addresses */ +typedef struct { + private_kernel_pfroute_net_t* this; + /** whether to enumerate down interfaces */ + bool include_down_ifaces; + /** whether to enumerate virtual ip addresses */ + bool include_virtual_ips; +} address_enumerator_t; + +/** + * cleanup function for address enumerator + */ +static void address_enumerator_destroy(address_enumerator_t *data) +{ + data->this->mutex->unlock(data->this->mutex); + free(data); +} + +/** + * filter for addresses + */ +static bool filter_addresses(address_enumerator_t *data, addr_entry_t** in, host_t** out) +{ + host_t *ip; + if (!data->include_virtual_ips && (*in)->virtual) + { /* skip virtual interfaces added by us */ + return FALSE; + } + ip = (*in)->ip; + if (ip->get_family(ip) == AF_INET6) + { + struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)ip->get_sockaddr(ip); + if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) + { /* skip addresses with a unusable scope */ + return FALSE; + } + } + *out = ip; + return TRUE; +} + +/** + * enumerator constructor for interfaces + */ +static enumerator_t *create_iface_enumerator(iface_entry_t *iface, address_enumerator_t *data) +{ + return enumerator_create_filter(iface->addrs->create_enumerator(iface->addrs), + (void*)filter_addresses, data, NULL); +} + +/** + * filter for interfaces + */ +static bool filter_interfaces(address_enumerator_t *data, iface_entry_t** in, iface_entry_t** out) +{ + if (!data->include_down_ifaces && !((*in)->flags & IFF_UP)) + { /* skip interfaces not up */ + return FALSE; + } + *out = *in; + return TRUE; +} + +/** + * implementation of kernel_net_t.create_address_enumerator + */ +static enumerator_t *create_address_enumerator(private_kernel_pfroute_net_t *this, + bool include_down_ifaces, bool include_virtual_ips) +{ + address_enumerator_t *data = malloc_thing(address_enumerator_t); + data->this = this; + data->include_down_ifaces = include_down_ifaces; + data->include_virtual_ips = include_virtual_ips; + + this->mutex->lock(this->mutex); + return enumerator_create_nested( + enumerator_create_filter(this->ifaces->create_enumerator(this->ifaces), + (void*)filter_interfaces, data, NULL), + (void*)create_iface_enumerator, data, (void*)address_enumerator_destroy); +} + +/** + * implementation of kernel_net_t.get_interface_name + */ +static char *get_interface_name(private_kernel_pfroute_net_t *this, host_t* ip) +{ + enumerator_t *ifaces, *addrs; + iface_entry_t *iface; + addr_entry_t *addr; + char *name = NULL; + + DBG2(DBG_KNL, "getting interface name for %H", ip); + + this->mutex->lock(this->mutex); + ifaces = this->ifaces->create_enumerator(this->ifaces); + while (ifaces->enumerate(ifaces, &iface)) + { + addrs = iface->addrs->create_enumerator(iface->addrs); + while (addrs->enumerate(addrs, &addr)) + { + if (ip->ip_equals(ip, addr->ip)) + { + name = strdup(iface->ifname); + break; + } + } + addrs->destroy(addrs); + if (name) + { + break; + } + } + ifaces->destroy(ifaces); + this->mutex->unlock(this->mutex); + + if (name) + { + DBG2(DBG_KNL, "%H is on interface %s", ip, name); + } + else + { + DBG2(DBG_KNL, "%H is not a local address", ip); + } + return name; +} + +/** + * Implementation of kernel_net_t.get_source_addr. + */ +static host_t* get_source_addr(private_kernel_pfroute_net_t *this, + host_t *dest, host_t *src) +{ + return NULL; +} + +/** + * Implementation of kernel_net_t.get_nexthop. + */ +static host_t* get_nexthop(private_kernel_pfroute_net_t *this, host_t *dest) +{ + return NULL; +} + +/** + * Implementation of kernel_net_t.add_ip. + */ +static status_t add_ip(private_kernel_pfroute_net_t *this, + host_t *virtual_ip, host_t *iface_ip) +{ + return FAILED; +} + +/** + * Implementation of kernel_net_t.del_ip. + */ +static status_t del_ip(private_kernel_pfroute_net_t *this, host_t *virtual_ip) +{ + return FAILED; +} + +/** + * Implementation of kernel_net_t.add_route. + */ +static status_t add_route(private_kernel_pfroute_net_t *this, chunk_t dst_net, + u_int8_t prefixlen, host_t *gateway, host_t *src_ip, char *if_name) +{ + return FAILED; +} + +/** + * Implementation of kernel_net_t.del_route. + */ +static status_t del_route(private_kernel_pfroute_net_t *this, chunk_t dst_net, + u_int8_t prefixlen, host_t *gateway, host_t *src_ip, char *if_name) +{ + return FAILED; +} + +/** + * Initialize a list of local addresses. + */ +static status_t init_address_list(private_kernel_pfroute_net_t *this) +{ + struct ifaddrs *ifap, *ifa; + iface_entry_t *iface, *current; + addr_entry_t *addr; + enumerator_t *ifaces, *addrs; + + DBG1(DBG_KNL, "listening on interfaces:"); + + if (getifaddrs(&ifap) < 0) + { + DBG1(DBG_KNL, " failed to get interfaces!"); + return FAILED; + } + + for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) + { + if (ifa->ifa_addr == NULL) + { + continue; + } + switch(ifa->ifa_addr->sa_family) + { + case AF_LINK: + case AF_INET: + case AF_INET6: + { + if (ifa->ifa_flags & IFF_LOOPBACK) + { /* ignore loopback interfaces */ + continue; + } + + iface = NULL; + ifaces = this->ifaces->create_enumerator(this->ifaces); + while (ifaces->enumerate(ifaces, ¤t)) + { + if (streq(current->ifname, ifa->ifa_name)) + { + iface = current; + break; + } + } + ifaces->destroy(ifaces); + + if (!iface) + { + iface = malloc_thing(iface_entry_t); + memcpy(iface->ifname, ifa->ifa_name, IFNAMSIZ); + iface->ifindex = if_nametoindex(ifa->ifa_name); + iface->flags = ifa->ifa_flags; + iface->addrs = linked_list_create(); + this->ifaces->insert_last(this->ifaces, iface); + } + + if (ifa->ifa_addr->sa_family != AF_LINK) + { + addr = malloc_thing(addr_entry_t); + addr->ip = host_create_from_sockaddr(ifa->ifa_addr); + addr->virtual = FALSE; + addr->refcount = 1; + iface->addrs->insert_last(iface->addrs, addr); + } + } + } + } + freeifaddrs(ifap); + + ifaces = this->ifaces->create_enumerator(this->ifaces); + while (ifaces->enumerate(ifaces, &iface)) + { + if (iface->flags & IFF_UP) + { + DBG1(DBG_KNL, " %s", iface->ifname); + addrs = iface->addrs->create_enumerator(iface->addrs); + while (addrs->enumerate(addrs, (void**)&addr)) + { + DBG1(DBG_KNL, " %H", addr->ip); + } + addrs->destroy(addrs); + } + } + ifaces->destroy(ifaces); + + return SUCCESS; +} + +/** + * Implementation of kernel_netlink_net_t.destroy. + */ +static void destroy(private_kernel_pfroute_net_t *this) +{ + if (this->job) + { + this->job->cancel(this->job); + } + if (this->socket > 0) + { + close(this->socket); + } + if (this->socket_events) + { + close(this->socket_events); + } + this->ifaces->destroy_function(this->ifaces, (void*)iface_entry_destroy); + this->mutex->destroy(this->mutex); + this->mutex_pfroute->destroy(this->mutex_pfroute); + free(this); +} + +/* + * Described in header. + */ +kernel_pfroute_net_t *kernel_pfroute_net_create() +{ + private_kernel_pfroute_net_t *this = malloc_thing(private_kernel_pfroute_net_t); + + /* public functions */ + this->public.interface.get_interface = (char*(*)(kernel_net_t*,host_t*))get_interface_name; + this->public.interface.create_address_enumerator = (enumerator_t*(*)(kernel_net_t*,bool,bool))create_address_enumerator; + this->public.interface.get_source_addr = (host_t*(*)(kernel_net_t*, host_t *dest, host_t *src))get_source_addr; + this->public.interface.get_nexthop = (host_t*(*)(kernel_net_t*, host_t *dest))get_nexthop; + this->public.interface.add_ip = (status_t(*)(kernel_net_t*,host_t*,host_t*)) add_ip; + this->public.interface.del_ip = (status_t(*)(kernel_net_t*,host_t*)) del_ip; + this->public.interface.add_route = (status_t(*)(kernel_net_t*,chunk_t,u_int8_t,host_t*,host_t*,char*)) add_route; + this->public.interface.del_route = (status_t(*)(kernel_net_t*,chunk_t,u_int8_t,host_t*,host_t*,char*)) del_route; + + this->public.interface.destroy = (void(*)(kernel_net_t*)) destroy; + + /* private members */ + this->ifaces = linked_list_create(); + this->mutex = mutex_create(MUTEX_TYPE_DEFAULT); + this->mutex_pfroute = mutex_create(MUTEX_TYPE_DEFAULT); + + this->seq = 0; + this->socket_events = 0; + this->job = NULL; + + /* create a PF_ROUTE socket to communicate with the kernel */ + this->socket = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC); + if (this->socket < 0) + { + DBG1(DBG_KNL, "unable to create PF_ROUTE socket"); + destroy(this); + return NULL; + } + + /* create a PF_ROUTE socket to receive events */ + this->socket_events = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC); + if (this->socket_events < 0) + { + DBG1(DBG_KNL, "unable to create PF_ROUTE event socket"); + destroy(this); + return NULL; + } + + this->job = callback_job_create((callback_job_cb_t)receive_events, + this, NULL, NULL); + hydra->processor->queue_job(hydra->processor, (job_t*)this->job); + + if (init_address_list(this) != SUCCESS) + { + DBG1(DBG_KNL, "unable to get interface list"); + destroy(this); + return NULL; + } + + return &this->public; +} |