mirror of
https://gitlab.nic.cz/labs/bird.git
synced 2024-11-08 20:28:43 +00:00
1756 lines
40 KiB
C
1756 lines
40 KiB
C
/*
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* BIRD -- Linux Netlink Interface
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*
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* (c) 1999--2000 Martin Mares <mj@ucw.cz>
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*
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* Can be freely distributed and used under the terms of the GNU GPL.
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*/
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#include <stdio.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include <sys/socket.h>
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#include <sys/uio.h>
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#include <errno.h>
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#undef LOCAL_DEBUG
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#include "nest/bird.h"
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#include "nest/route.h"
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#include "nest/protocol.h"
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#include "nest/iface.h"
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#include "lib/timer.h"
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#include "lib/unix.h"
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#include "lib/krt.h"
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#include "lib/socket.h"
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#include "lib/string.h"
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#include "lib/hash.h"
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#include "conf/conf.h"
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#include <asm/types.h>
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#include <linux/if.h>
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#include <linux/netlink.h>
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#include <linux/rtnetlink.h>
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#ifndef MSG_TRUNC /* Hack: Several versions of glibc miss this one :( */
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#define MSG_TRUNC 0x20
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#endif
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#ifndef IFA_FLAGS
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#define IFA_FLAGS 8
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#endif
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#ifndef IFF_LOWER_UP
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#define IFF_LOWER_UP 0x10000
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#endif
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#ifndef RTA_TABLE
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#define RTA_TABLE 15
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#endif
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#ifdef IPV6
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#define krt_ecmp6(X) 1
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#else
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#define krt_ecmp6(X) 0
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#endif
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/*
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* Structure nl_parse_state keeps state of received route processing. Ideally,
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* we could just independently parse received Netlink messages and immediately
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* propagate received routes to the rest of BIRD, but older Linux kernel (before
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* version 4.11) represents and announces IPv6 ECMP routes not as one route with
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* multiple next hops (like RTA_MULTIPATH in IPv4 ECMP), but as a sequence of
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* routes with the same prefix. More recent kernels work as with IPv4.
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*
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* Therefore, BIRD keeps currently processed route in nl_parse_state structure
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* and postpones its propagation until we expect it to be final; i.e., when
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* non-matching route is received or when the scan ends. When another matching
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* route is received, it is merged with the already processed route to form an
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* ECMP route. Note that merging is done only for IPv6 (merge == 1), but the
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* postponing is done in both cases (for simplicity). All IPv4 routes or IPv6
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* routes with RTA_MULTIPATH set are just considered non-matching.
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*
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* This is ignored for asynchronous notifications (every notification is handled
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* as a separate route). It is not an issue for our routes, as we ignore such
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* notifications anyways. But importing alien IPv6 ECMP routes does not work
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* properly with older kernels.
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*
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* Whatever the kernel version is, IPv6 ECMP routes are sent as multiple routes
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* for the same prefix.
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*/
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struct nl_parse_state
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{
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struct linpool *pool;
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int scan;
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int merge;
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net *net;
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rta *attrs;
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struct krt_proto *proto;
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s8 new;
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s8 krt_src;
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u8 krt_type;
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u8 krt_proto;
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u32 krt_metric;
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};
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/*
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* Synchronous Netlink interface
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*/
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struct nl_sock
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{
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int fd;
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u32 seq;
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byte *rx_buffer; /* Receive buffer */
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struct nlmsghdr *last_hdr; /* Recently received packet */
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uint last_size;
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};
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#define NL_RX_SIZE 8192
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#define NL_OP_DELETE 0
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#define NL_OP_ADD (NLM_F_CREATE|NLM_F_EXCL)
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#define NL_OP_REPLACE (NLM_F_CREATE|NLM_F_REPLACE)
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#define NL_OP_APPEND (NLM_F_CREATE|NLM_F_APPEND)
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static linpool *nl_linpool;
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static struct nl_sock nl_scan = {.fd = -1}; /* Netlink socket for synchronous scan */
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static struct nl_sock nl_req = {.fd = -1}; /* Netlink socket for requests */
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static void
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nl_open_sock(struct nl_sock *nl)
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{
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if (nl->fd < 0)
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{
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nl->fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
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if (nl->fd < 0)
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die("Unable to open rtnetlink socket: %m");
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nl->seq = now;
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nl->rx_buffer = xmalloc(NL_RX_SIZE);
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nl->last_hdr = NULL;
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nl->last_size = 0;
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}
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}
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static void
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nl_open(void)
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{
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nl_open_sock(&nl_scan);
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nl_open_sock(&nl_req);
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}
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static void
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nl_send(struct nl_sock *nl, struct nlmsghdr *nh)
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{
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struct sockaddr_nl sa;
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memset(&sa, 0, sizeof(sa));
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sa.nl_family = AF_NETLINK;
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nh->nlmsg_pid = 0;
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nh->nlmsg_seq = ++(nl->seq);
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if (sendto(nl->fd, nh, nh->nlmsg_len, 0, (struct sockaddr *)&sa, sizeof(sa)) < 0)
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die("rtnetlink sendto: %m");
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nl->last_hdr = NULL;
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}
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static void
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nl_request_dump(int af, int cmd)
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{
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struct {
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struct nlmsghdr nh;
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struct rtgenmsg g;
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} req = {
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.nh.nlmsg_type = cmd,
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.nh.nlmsg_len = sizeof(req),
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.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP,
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.g.rtgen_family = af
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};
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nl_send(&nl_scan, &req.nh);
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}
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static struct nlmsghdr *
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nl_get_reply(struct nl_sock *nl)
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{
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for(;;)
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{
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if (!nl->last_hdr)
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{
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struct iovec iov = { nl->rx_buffer, NL_RX_SIZE };
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struct sockaddr_nl sa;
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struct msghdr m = {
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.msg_name = &sa,
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.msg_namelen = sizeof(sa),
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.msg_iov = &iov,
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.msg_iovlen = 1,
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};
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int x = recvmsg(nl->fd, &m, 0);
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if (x < 0)
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die("nl_get_reply: %m");
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if (sa.nl_pid) /* It isn't from the kernel */
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{
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DBG("Non-kernel packet\n");
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continue;
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}
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nl->last_size = x;
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nl->last_hdr = (void *) nl->rx_buffer;
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if (m.msg_flags & MSG_TRUNC)
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bug("nl_get_reply: got truncated reply which should be impossible");
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}
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if (NLMSG_OK(nl->last_hdr, nl->last_size))
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{
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struct nlmsghdr *h = nl->last_hdr;
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nl->last_hdr = NLMSG_NEXT(h, nl->last_size);
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if (h->nlmsg_seq != nl->seq)
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{
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log(L_WARN "nl_get_reply: Ignoring out of sequence netlink packet (%x != %x)",
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h->nlmsg_seq, nl->seq);
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continue;
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}
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return h;
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}
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if (nl->last_size)
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log(L_WARN "nl_get_reply: Found packet remnant of size %d", nl->last_size);
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nl->last_hdr = NULL;
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}
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}
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static struct tbf rl_netlink_err = TBF_DEFAULT_LOG_LIMITS;
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static int
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nl_error(struct nlmsghdr *h, int ignore_esrch)
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{
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struct nlmsgerr *e;
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int ec;
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if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr)))
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{
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log(L_WARN "Netlink: Truncated error message received");
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return ENOBUFS;
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}
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e = (struct nlmsgerr *) NLMSG_DATA(h);
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ec = -e->error;
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if (ec && !(ignore_esrch && (ec == ESRCH)))
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log_rl(&rl_netlink_err, L_WARN "Netlink: %s", strerror(ec));
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return ec;
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}
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static struct nlmsghdr *
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nl_get_scan(void)
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{
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struct nlmsghdr *h = nl_get_reply(&nl_scan);
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if (h->nlmsg_type == NLMSG_DONE)
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return NULL;
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if (h->nlmsg_type == NLMSG_ERROR)
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{
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nl_error(h, 0);
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return NULL;
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}
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return h;
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}
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static int
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nl_exchange(struct nlmsghdr *pkt, int ignore_esrch)
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{
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struct nlmsghdr *h;
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nl_send(&nl_req, pkt);
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for(;;)
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{
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h = nl_get_reply(&nl_req);
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if (h->nlmsg_type == NLMSG_ERROR)
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break;
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log(L_WARN "nl_exchange: Unexpected reply received");
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}
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return nl_error(h, ignore_esrch) ? -1 : 0;
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}
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/*
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* Netlink attributes
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*/
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static int nl_attr_len;
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static void *
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nl_checkin(struct nlmsghdr *h, int lsize)
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{
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nl_attr_len = h->nlmsg_len - NLMSG_LENGTH(lsize);
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if (nl_attr_len < 0)
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{
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log(L_ERR "nl_checkin: underrun by %d bytes", -nl_attr_len);
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return NULL;
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}
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return NLMSG_DATA(h);
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}
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struct nl_want_attrs {
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u8 defined:1;
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u8 checksize:1;
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u8 size;
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};
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#define BIRD_IFLA_MAX (IFLA_WIRELESS+1)
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static struct nl_want_attrs ifla_attr_want[BIRD_IFLA_MAX] = {
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[IFLA_IFNAME] = { 1, 0, 0 },
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[IFLA_MTU] = { 1, 1, sizeof(u32) },
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[IFLA_MASTER] = { 1, 1, sizeof(u32) },
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[IFLA_WIRELESS] = { 1, 0, 0 },
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};
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#define BIRD_IFA_MAX (IFA_FLAGS+1)
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#ifndef IPV6
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static struct nl_want_attrs ifa_attr_want4[BIRD_IFA_MAX] = {
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[IFA_ADDRESS] = { 1, 1, sizeof(ip4_addr) },
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[IFA_LOCAL] = { 1, 1, sizeof(ip4_addr) },
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[IFA_BROADCAST] = { 1, 1, sizeof(ip4_addr) },
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[IFA_FLAGS] = { 1, 1, sizeof(u32) },
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};
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#else
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static struct nl_want_attrs ifa_attr_want6[BIRD_IFA_MAX] = {
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[IFA_ADDRESS] = { 1, 1, sizeof(ip6_addr) },
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[IFA_LOCAL] = { 1, 1, sizeof(ip6_addr) },
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[IFA_FLAGS] = { 1, 1, sizeof(u32) },
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};
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#endif
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#define BIRD_RTA_MAX (RTA_TABLE+1)
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#ifndef IPV6
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static struct nl_want_attrs mpnh_attr_want4[BIRD_RTA_MAX] = {
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[RTA_GATEWAY] = { 1, 1, sizeof(ip4_addr) },
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};
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#else
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static struct nl_want_attrs mpnh_attr_want6[BIRD_RTA_MAX] = {
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[RTA_GATEWAY] = { 1, 1, sizeof(ip6_addr) },
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};
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#endif
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#ifndef IPV6
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static struct nl_want_attrs rtm_attr_want4[BIRD_RTA_MAX] = {
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[RTA_DST] = { 1, 1, sizeof(ip4_addr) },
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[RTA_OIF] = { 1, 1, sizeof(u32) },
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[RTA_GATEWAY] = { 1, 1, sizeof(ip4_addr) },
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[RTA_PRIORITY] = { 1, 1, sizeof(u32) },
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[RTA_PREFSRC] = { 1, 1, sizeof(ip4_addr) },
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[RTA_METRICS] = { 1, 0, 0 },
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[RTA_MULTIPATH] = { 1, 0, 0 },
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[RTA_FLOW] = { 1, 1, sizeof(u32) },
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[RTA_TABLE] = { 1, 1, sizeof(u32) },
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};
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#else
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static struct nl_want_attrs rtm_attr_want6[BIRD_RTA_MAX] = {
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[RTA_DST] = { 1, 1, sizeof(ip6_addr) },
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[RTA_IIF] = { 1, 1, sizeof(u32) },
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[RTA_OIF] = { 1, 1, sizeof(u32) },
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[RTA_GATEWAY] = { 1, 1, sizeof(ip6_addr) },
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[RTA_PRIORITY] = { 1, 1, sizeof(u32) },
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[RTA_PREFSRC] = { 1, 1, sizeof(ip6_addr) },
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[RTA_METRICS] = { 1, 0, 0 },
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[RTA_MULTIPATH] = { 1, 0, 0 },
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[RTA_FLOW] = { 1, 1, sizeof(u32) },
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[RTA_TABLE] = { 1, 1, sizeof(u32) },
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};
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#endif
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static int
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nl_parse_attrs(struct rtattr *a, struct nl_want_attrs *want, struct rtattr **k, int ksize)
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{
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int max = ksize / sizeof(struct rtattr *);
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bzero(k, ksize);
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for ( ; RTA_OK(a, nl_attr_len); a = RTA_NEXT(a, nl_attr_len))
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{
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if ((a->rta_type >= max) || !want[a->rta_type].defined)
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continue;
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if (want[a->rta_type].checksize && (RTA_PAYLOAD(a) != want[a->rta_type].size))
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{
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log(L_ERR "nl_parse_attrs: Malformed message received");
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return 0;
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}
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k[a->rta_type] = a;
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}
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if (nl_attr_len)
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{
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log(L_ERR "nl_parse_attrs: remnant of size %d", nl_attr_len);
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return 0;
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}
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return 1;
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}
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static inline u32 rta_get_u32(struct rtattr *a)
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{ return *(u32 *) RTA_DATA(a); }
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static inline ip4_addr rta_get_ip4(struct rtattr *a)
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{ return ip4_ntoh(*(ip4_addr *) RTA_DATA(a)); }
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static inline ip6_addr rta_get_ip6(struct rtattr *a)
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{ return ip6_ntoh(*(ip6_addr *) RTA_DATA(a)); }
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struct rtattr *
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nl_add_attr(struct nlmsghdr *h, uint bufsize, uint code, const void *data, uint dlen)
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{
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uint pos = NLMSG_ALIGN(h->nlmsg_len);
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uint len = RTA_LENGTH(dlen);
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if (pos + len > bufsize)
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bug("nl_add_attr: packet buffer overflow");
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struct rtattr *a = (struct rtattr *)((char *)h + pos);
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a->rta_type = code;
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a->rta_len = len;
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h->nlmsg_len = pos + len;
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if (dlen > 0)
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memcpy(RTA_DATA(a), data, dlen);
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return a;
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}
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static inline void
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nl_add_attr_u32(struct nlmsghdr *h, unsigned bufsize, int code, u32 data)
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{
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nl_add_attr(h, bufsize, code, &data, 4);
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}
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static inline void
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nl_add_attr_ipa(struct nlmsghdr *h, unsigned bufsize, int code, ip_addr ipa)
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{
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ipa_hton(ipa);
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nl_add_attr(h, bufsize, code, &ipa, sizeof(ipa));
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}
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static inline struct rtattr *
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nl_open_attr(struct nlmsghdr *h, uint bufsize, uint code)
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{
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return nl_add_attr(h, bufsize, code, NULL, 0);
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}
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static inline void
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nl_close_attr(struct nlmsghdr *h, struct rtattr *a)
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{
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a->rta_len = (void *)h + NLMSG_ALIGN(h->nlmsg_len) - (void *)a;
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}
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static inline struct rtnexthop *
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nl_open_nexthop(struct nlmsghdr *h, uint bufsize)
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{
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uint pos = NLMSG_ALIGN(h->nlmsg_len);
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uint len = RTNH_LENGTH(0);
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if (pos + len > bufsize)
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bug("nl_open_nexthop: packet buffer overflow");
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h->nlmsg_len = pos + len;
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return (void *)h + pos;
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}
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static inline void
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nl_close_nexthop(struct nlmsghdr *h, struct rtnexthop *nh)
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{
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nh->rtnh_len = (void *)h + NLMSG_ALIGN(h->nlmsg_len) - (void *)nh;
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}
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static void
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nl_add_multipath(struct nlmsghdr *h, unsigned bufsize, struct mpnh *nh)
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{
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struct rtattr *a = nl_open_attr(h, bufsize, RTA_MULTIPATH);
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for (; nh; nh = nh->next)
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{
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struct rtnexthop *rtnh = nl_open_nexthop(h, bufsize);
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rtnh->rtnh_flags = 0;
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rtnh->rtnh_hops = nh->weight;
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rtnh->rtnh_ifindex = nh->iface->index;
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nl_add_attr_ipa(h, bufsize, RTA_GATEWAY, nh->gw);
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nl_close_nexthop(h, rtnh);
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}
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nl_close_attr(h, a);
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}
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static struct mpnh *
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nl_parse_multipath(struct krt_proto *p, struct rtattr *ra, int af)
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{
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/* Temporary buffer for multicast nexthops */
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static struct mpnh *nh_buffer;
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static int nh_buf_size; /* in number of structures */
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static int nh_buf_used;
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struct rtattr *a[BIRD_RTA_MAX];
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struct rtnexthop *nh = RTA_DATA(ra);
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struct mpnh *rv, *first, **last;
|
|
unsigned len = RTA_PAYLOAD(ra);
|
|
|
|
first = NULL;
|
|
last = &first;
|
|
nh_buf_used = 0;
|
|
|
|
while (len)
|
|
{
|
|
/* Use RTNH_OK(nh,len) ?? */
|
|
if ((len < sizeof(*nh)) || (len < nh->rtnh_len))
|
|
return NULL;
|
|
|
|
if (nh_buf_used == nh_buf_size)
|
|
{
|
|
nh_buf_size = nh_buf_size ? (nh_buf_size * 2) : 4;
|
|
nh_buffer = xrealloc(nh_buffer, nh_buf_size * sizeof(struct mpnh));
|
|
}
|
|
*last = rv = nh_buffer + nh_buf_used++;
|
|
rv->next = NULL;
|
|
last = &(rv->next);
|
|
|
|
rv->weight = nh->rtnh_hops;
|
|
rv->iface = if_find_by_index(nh->rtnh_ifindex);
|
|
if (!rv->iface)
|
|
return NULL;
|
|
|
|
/* Nonexistent RTNH_PAYLOAD ?? */
|
|
nl_attr_len = nh->rtnh_len - RTNH_LENGTH(0);
|
|
switch (af)
|
|
{
|
|
#ifndef IPV6
|
|
case AF_INET:
|
|
if (!nl_parse_attrs(RTNH_DATA(nh), mpnh_attr_want4, a, sizeof(a)))
|
|
return NULL;
|
|
break;
|
|
#else
|
|
case AF_INET6:
|
|
if (!nl_parse_attrs(RTNH_DATA(nh), mpnh_attr_want6, a, sizeof(a)))
|
|
return NULL;
|
|
break;
|
|
#endif
|
|
default:
|
|
return NULL;
|
|
}
|
|
|
|
if (a[RTA_GATEWAY])
|
|
{
|
|
memcpy(&rv->gw, RTA_DATA(a[RTA_GATEWAY]), sizeof(rv->gw));
|
|
ipa_ntoh(rv->gw);
|
|
|
|
neighbor *ng = neigh_find2(&p->p, &rv->gw, rv->iface,
|
|
(nh->rtnh_flags & RTNH_F_ONLINK) ? NEF_ONLINK : 0);
|
|
if (!ng || (ng->scope == SCOPE_HOST))
|
|
return NULL;
|
|
}
|
|
else
|
|
return NULL;
|
|
|
|
len -= NLMSG_ALIGN(nh->rtnh_len);
|
|
nh = RTNH_NEXT(nh);
|
|
}
|
|
|
|
return first;
|
|
}
|
|
|
|
static void
|
|
nl_add_metrics(struct nlmsghdr *h, uint bufsize, u32 *metrics, int max)
|
|
{
|
|
struct rtattr *a = nl_open_attr(h, bufsize, RTA_METRICS);
|
|
int t;
|
|
|
|
for (t = 1; t < max; t++)
|
|
if (metrics[0] & (1 << t))
|
|
nl_add_attr_u32(h, bufsize, t, metrics[t]);
|
|
|
|
nl_close_attr(h, a);
|
|
}
|
|
|
|
static int
|
|
nl_parse_metrics(struct rtattr *hdr, u32 *metrics, int max)
|
|
{
|
|
struct rtattr *a = RTA_DATA(hdr);
|
|
int len = RTA_PAYLOAD(hdr);
|
|
|
|
metrics[0] = 0;
|
|
for (; RTA_OK(a, len); a = RTA_NEXT(a, len))
|
|
{
|
|
if (a->rta_type == RTA_UNSPEC)
|
|
continue;
|
|
|
|
if (a->rta_type >= max)
|
|
continue;
|
|
|
|
if (RTA_PAYLOAD(a) != 4)
|
|
return -1;
|
|
|
|
metrics[0] |= 1 << a->rta_type;
|
|
metrics[a->rta_type] = rta_get_u32(a);
|
|
}
|
|
|
|
if (len > 0)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* Scanning of interfaces
|
|
*/
|
|
|
|
static void
|
|
nl_parse_link(struct nlmsghdr *h, int scan)
|
|
{
|
|
struct ifinfomsg *i;
|
|
struct rtattr *a[BIRD_IFLA_MAX];
|
|
int new = h->nlmsg_type == RTM_NEWLINK;
|
|
struct iface f = {};
|
|
struct iface *ifi;
|
|
char *name;
|
|
u32 mtu, master = 0;
|
|
uint fl;
|
|
|
|
if (!(i = nl_checkin(h, sizeof(*i))) || !nl_parse_attrs(IFLA_RTA(i), ifla_attr_want, a, sizeof(a)))
|
|
return;
|
|
if (!a[IFLA_IFNAME] || (RTA_PAYLOAD(a[IFLA_IFNAME]) < 2) || !a[IFLA_MTU])
|
|
{
|
|
/*
|
|
* IFLA_IFNAME and IFLA_MTU are required, in fact, but there may also come
|
|
* a message with IFLA_WIRELESS set, where (e.g.) no IFLA_IFNAME exists.
|
|
* We simply ignore all such messages with IFLA_WIRELESS without notice.
|
|
*/
|
|
|
|
if (a[IFLA_WIRELESS])
|
|
return;
|
|
|
|
log(L_ERR "KIF: Malformed message received");
|
|
return;
|
|
}
|
|
|
|
name = RTA_DATA(a[IFLA_IFNAME]);
|
|
mtu = rta_get_u32(a[IFLA_MTU]);
|
|
|
|
if (a[IFLA_MASTER])
|
|
master = rta_get_u32(a[IFLA_MASTER]);
|
|
|
|
ifi = if_find_by_index(i->ifi_index);
|
|
if (!new)
|
|
{
|
|
DBG("KIF: IF%d(%s) goes down\n", i->ifi_index, name);
|
|
if (!ifi)
|
|
return;
|
|
|
|
if_delete(ifi);
|
|
}
|
|
else
|
|
{
|
|
DBG("KIF: IF%d(%s) goes up (mtu=%d,flg=%x)\n", i->ifi_index, name, mtu, i->ifi_flags);
|
|
if (ifi && strncmp(ifi->name, name, sizeof(ifi->name)-1))
|
|
if_delete(ifi);
|
|
|
|
strncpy(f.name, name, sizeof(f.name)-1);
|
|
f.index = i->ifi_index;
|
|
f.mtu = mtu;
|
|
|
|
f.master_index = master;
|
|
f.master = if_find_by_index(master);
|
|
|
|
fl = i->ifi_flags;
|
|
if (fl & IFF_UP)
|
|
f.flags |= IF_ADMIN_UP;
|
|
if (fl & IFF_LOWER_UP)
|
|
f.flags |= IF_LINK_UP;
|
|
if (fl & IFF_LOOPBACK) /* Loopback */
|
|
f.flags |= IF_MULTIACCESS | IF_LOOPBACK | IF_IGNORE;
|
|
else if (fl & IFF_POINTOPOINT) /* PtP */
|
|
f.flags |= IF_MULTICAST;
|
|
else if (fl & IFF_BROADCAST) /* Broadcast */
|
|
f.flags |= IF_MULTIACCESS | IF_BROADCAST | IF_MULTICAST;
|
|
else
|
|
f.flags |= IF_MULTIACCESS; /* NBMA */
|
|
|
|
if (fl & IFF_MULTICAST)
|
|
f.flags |= IF_MULTICAST;
|
|
|
|
ifi = if_update(&f);
|
|
|
|
if (!scan)
|
|
if_end_partial_update(ifi);
|
|
}
|
|
}
|
|
|
|
static void
|
|
nl_parse_addr(struct nlmsghdr *h, int scan)
|
|
{
|
|
struct ifaddrmsg *i;
|
|
struct rtattr *a[BIRD_IFA_MAX];
|
|
int new = h->nlmsg_type == RTM_NEWADDR;
|
|
struct ifa ifa;
|
|
struct iface *ifi;
|
|
int scope;
|
|
u32 ifa_flags;
|
|
|
|
if (!(i = nl_checkin(h, sizeof(*i))))
|
|
return;
|
|
|
|
switch (i->ifa_family)
|
|
{
|
|
#ifndef IPV6
|
|
case AF_INET:
|
|
if (!nl_parse_attrs(IFA_RTA(i), ifa_attr_want4, a, sizeof(a)))
|
|
return;
|
|
if (!a[IFA_LOCAL])
|
|
{
|
|
log(L_ERR "KIF: Malformed message received (missing IFA_LOCAL)");
|
|
return;
|
|
}
|
|
break;
|
|
#else
|
|
case AF_INET6:
|
|
if (!nl_parse_attrs(IFA_RTA(i), ifa_attr_want6, a, sizeof(a)))
|
|
return;
|
|
break;
|
|
#endif
|
|
default:
|
|
return;
|
|
}
|
|
|
|
if (!a[IFA_ADDRESS])
|
|
{
|
|
log(L_ERR "KIF: Malformed message received (missing IFA_ADDRESS)");
|
|
return;
|
|
}
|
|
|
|
if (a[IFA_FLAGS])
|
|
ifa_flags = rta_get_u32(a[IFA_FLAGS]);
|
|
else
|
|
ifa_flags = i->ifa_flags;
|
|
|
|
ifi = if_find_by_index(i->ifa_index);
|
|
if (!ifi)
|
|
{
|
|
log(L_ERR "KIF: Received address message for unknown interface %d", i->ifa_index);
|
|
return;
|
|
}
|
|
|
|
bzero(&ifa, sizeof(ifa));
|
|
ifa.iface = ifi;
|
|
if (ifa_flags & IFA_F_SECONDARY)
|
|
ifa.flags |= IA_SECONDARY;
|
|
|
|
#ifdef IPV6
|
|
/* Ignore tentative addresses silently */
|
|
if (ifa_flags & IFA_F_TENTATIVE)
|
|
return;
|
|
#endif
|
|
|
|
/* IFA_LOCAL can be unset for IPv6 interfaces */
|
|
memcpy(&ifa.ip, RTA_DATA(a[IFA_LOCAL] ? : a[IFA_ADDRESS]), sizeof(ifa.ip));
|
|
ipa_ntoh(ifa.ip);
|
|
ifa.pxlen = i->ifa_prefixlen;
|
|
if (i->ifa_prefixlen > BITS_PER_IP_ADDRESS)
|
|
{
|
|
log(L_ERR "KIF: Invalid prefix length for interface %s: %d", ifi->name, i->ifa_prefixlen);
|
|
new = 0;
|
|
}
|
|
if (i->ifa_prefixlen == BITS_PER_IP_ADDRESS)
|
|
{
|
|
ip_addr addr;
|
|
memcpy(&addr, RTA_DATA(a[IFA_ADDRESS]), sizeof(addr));
|
|
ipa_ntoh(addr);
|
|
ifa.prefix = ifa.brd = addr;
|
|
|
|
/* It is either a host address or a peer address */
|
|
if (ipa_equal(ifa.ip, addr))
|
|
ifa.flags |= IA_HOST;
|
|
else
|
|
{
|
|
ifa.flags |= IA_PEER;
|
|
ifa.opposite = addr;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
ip_addr netmask = ipa_mkmask(ifa.pxlen);
|
|
ifa.prefix = ipa_and(ifa.ip, netmask);
|
|
ifa.brd = ipa_or(ifa.ip, ipa_not(netmask));
|
|
if (i->ifa_prefixlen == BITS_PER_IP_ADDRESS - 1)
|
|
ifa.opposite = ipa_opposite_m1(ifa.ip);
|
|
|
|
#ifndef IPV6
|
|
if (i->ifa_prefixlen == BITS_PER_IP_ADDRESS - 2)
|
|
ifa.opposite = ipa_opposite_m2(ifa.ip);
|
|
|
|
if ((ifi->flags & IF_BROADCAST) && a[IFA_BROADCAST])
|
|
{
|
|
ip_addr xbrd;
|
|
memcpy(&xbrd, RTA_DATA(a[IFA_BROADCAST]), sizeof(xbrd));
|
|
ipa_ntoh(xbrd);
|
|
if (ipa_equal(xbrd, ifa.prefix) || ipa_equal(xbrd, ifa.brd))
|
|
ifa.brd = xbrd;
|
|
else if (ifi->flags & IF_TMP_DOWN) /* Complain only during the first scan */
|
|
log(L_ERR "KIF: Invalid broadcast address %I for %s", xbrd, ifi->name);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
scope = ipa_classify(ifa.ip);
|
|
if (scope < 0)
|
|
{
|
|
log(L_ERR "KIF: Invalid interface address %I for %s", ifa.ip, ifi->name);
|
|
return;
|
|
}
|
|
ifa.scope = scope & IADDR_SCOPE_MASK;
|
|
|
|
DBG("KIF: IF%d(%s): %s IPA %I, flg %x, net %I/%d, brd %I, opp %I\n",
|
|
ifi->index, ifi->name,
|
|
new ? "added" : "removed",
|
|
ifa.ip, ifa.flags, ifa.prefix, ifa.pxlen, ifa.brd, ifa.opposite);
|
|
|
|
if (new)
|
|
ifa_update(&ifa);
|
|
else
|
|
ifa_delete(&ifa);
|
|
|
|
if (!scan)
|
|
if_end_partial_update(ifi);
|
|
}
|
|
|
|
void
|
|
kif_do_scan(struct kif_proto *p UNUSED)
|
|
{
|
|
struct nlmsghdr *h;
|
|
|
|
if_start_update();
|
|
|
|
nl_request_dump(AF_UNSPEC, RTM_GETLINK);
|
|
while (h = nl_get_scan())
|
|
if (h->nlmsg_type == RTM_NEWLINK || h->nlmsg_type == RTM_DELLINK)
|
|
nl_parse_link(h, 1);
|
|
else
|
|
log(L_DEBUG "nl_scan_ifaces: Unknown packet received (type=%d)", h->nlmsg_type);
|
|
|
|
/* Re-resolve master interface for slaves */
|
|
struct iface *i;
|
|
WALK_LIST(i, iface_list)
|
|
if (i->master_index)
|
|
{
|
|
struct iface f = {
|
|
.flags = i->flags,
|
|
.mtu = i->mtu,
|
|
.index = i->index,
|
|
.master_index = i->master_index,
|
|
.master = if_find_by_index(i->master_index)
|
|
};
|
|
|
|
if (f.master != i->master)
|
|
{
|
|
memcpy(f.name, i->name, sizeof(f.name));
|
|
if_update(&f);
|
|
}
|
|
}
|
|
|
|
nl_request_dump(BIRD_AF, RTM_GETADDR);
|
|
while (h = nl_get_scan())
|
|
if (h->nlmsg_type == RTM_NEWADDR || h->nlmsg_type == RTM_DELADDR)
|
|
nl_parse_addr(h, 1);
|
|
else
|
|
log(L_DEBUG "nl_scan_ifaces: Unknown packet received (type=%d)", h->nlmsg_type);
|
|
|
|
if_end_update();
|
|
}
|
|
|
|
/*
|
|
* Routes
|
|
*/
|
|
|
|
static inline u32
|
|
krt_table_id(struct krt_proto *p)
|
|
{
|
|
return KRT_CF->sys.table_id;
|
|
}
|
|
|
|
static HASH(struct krt_proto) nl_table_map;
|
|
|
|
#define RTH_FN(k) u32_hash(k)
|
|
#define RTH_EQ(k1,k2) k1 == k2
|
|
#define RTH_KEY(p) krt_table_id(p)
|
|
#define RTH_NEXT(p) p->sys.hash_next
|
|
|
|
#define RTH_REHASH rth_rehash
|
|
#define RTH_PARAMS /8, *2, 2, 2, 6, 20
|
|
|
|
HASH_DEFINE_REHASH_FN(RTH, struct krt_proto)
|
|
|
|
int
|
|
krt_capable(rte *e)
|
|
{
|
|
rta *a = e->attrs;
|
|
|
|
if (a->cast != RTC_UNICAST)
|
|
return 0;
|
|
|
|
switch (a->dest)
|
|
{
|
|
case RTD_ROUTER:
|
|
case RTD_DEVICE:
|
|
if (a->iface == NULL)
|
|
return 0;
|
|
case RTD_BLACKHOLE:
|
|
case RTD_UNREACHABLE:
|
|
case RTD_PROHIBIT:
|
|
case RTD_MULTIPATH:
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static inline int
|
|
nh_bufsize(struct mpnh *nh)
|
|
{
|
|
int rv = 0;
|
|
for (; nh != NULL; nh = nh->next)
|
|
rv += RTNH_LENGTH(RTA_LENGTH(sizeof(ip_addr)));
|
|
return rv;
|
|
}
|
|
|
|
static int
|
|
nl_send_route(struct krt_proto *p, rte *e, struct ea_list *eattrs, int op, int dest, ip_addr gw, struct iface *iface)
|
|
{
|
|
eattr *ea;
|
|
net *net = e->net;
|
|
rta *a = e->attrs;
|
|
u32 priority = 0;
|
|
|
|
struct {
|
|
struct nlmsghdr h;
|
|
struct rtmsg r;
|
|
char buf[0];
|
|
} *r;
|
|
|
|
uint rsize = sizeof(*r) + 128 + KRT_METRICS_MAX*8 + nh_bufsize(a->nexthops);
|
|
r = alloca(rsize);
|
|
|
|
DBG("nl_send_route(%I/%d,op=%x)\n", net->n.prefix, net->n.pxlen, op);
|
|
|
|
bzero(&r->h, sizeof(r->h));
|
|
bzero(&r->r, sizeof(r->r));
|
|
r->h.nlmsg_type = op ? RTM_NEWROUTE : RTM_DELROUTE;
|
|
r->h.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
|
|
r->h.nlmsg_flags = op | NLM_F_REQUEST | NLM_F_ACK;
|
|
|
|
r->r.rtm_family = BIRD_AF;
|
|
r->r.rtm_dst_len = net->n.pxlen;
|
|
r->r.rtm_protocol = RTPROT_BIRD;
|
|
r->r.rtm_scope = RT_SCOPE_NOWHERE;
|
|
nl_add_attr_ipa(&r->h, rsize, RTA_DST, net->n.prefix);
|
|
|
|
/*
|
|
* Strange behavior for RTM_DELROUTE:
|
|
* 1) rtm_family is ignored in IPv6, works for IPv4
|
|
* 2) not setting RTA_PRIORITY is different from setting default value (on IPv6)
|
|
* 3) not setting RTA_PRIORITY is equivalent to setting 0, which is wildcard
|
|
*/
|
|
|
|
if (krt_table_id(p) < 256)
|
|
r->r.rtm_table = krt_table_id(p);
|
|
else
|
|
nl_add_attr_u32(&r->h, rsize, RTA_TABLE, krt_table_id(p));
|
|
|
|
if (a->source == RTS_DUMMY)
|
|
priority = e->u.krt.metric;
|
|
else if (KRT_CF->sys.metric)
|
|
priority = KRT_CF->sys.metric;
|
|
else if ((op != NL_OP_DELETE) && (ea = ea_find(eattrs, EA_KRT_METRIC)))
|
|
priority = ea->u.data;
|
|
|
|
if (priority)
|
|
nl_add_attr_u32(&r->h, rsize, RTA_PRIORITY, priority);
|
|
|
|
/* For route delete, we do not specify remaining route attributes */
|
|
if (op == NL_OP_DELETE)
|
|
goto dest;
|
|
|
|
/* Default scope is LINK for device routes, UNIVERSE otherwise */
|
|
if (ea = ea_find(eattrs, EA_KRT_SCOPE))
|
|
r->r.rtm_scope = ea->u.data;
|
|
else
|
|
r->r.rtm_scope = (dest == RTD_DEVICE) ? RT_SCOPE_LINK : RT_SCOPE_UNIVERSE;
|
|
|
|
if (ea = ea_find(eattrs, EA_KRT_PREFSRC))
|
|
nl_add_attr_ipa(&r->h, rsize, RTA_PREFSRC, *(ip_addr *)ea->u.ptr->data);
|
|
|
|
if (ea = ea_find(eattrs, EA_KRT_REALM))
|
|
nl_add_attr_u32(&r->h, rsize, RTA_FLOW, ea->u.data);
|
|
|
|
|
|
u32 metrics[KRT_METRICS_MAX];
|
|
metrics[0] = 0;
|
|
|
|
struct ea_walk_state ews = { .eattrs = eattrs };
|
|
while (ea = ea_walk(&ews, EA_KRT_METRICS, KRT_METRICS_MAX))
|
|
{
|
|
int id = ea->id - EA_KRT_METRICS;
|
|
metrics[0] |= 1 << id;
|
|
metrics[id] = ea->u.data;
|
|
}
|
|
|
|
if (metrics[0])
|
|
nl_add_metrics(&r->h, rsize, metrics, KRT_METRICS_MAX);
|
|
|
|
|
|
dest:
|
|
/* a->iface != NULL checked in krt_capable() for router and device routes */
|
|
switch (dest)
|
|
{
|
|
case RTD_ROUTER:
|
|
r->r.rtm_type = RTN_UNICAST;
|
|
nl_add_attr_u32(&r->h, rsize, RTA_OIF, iface->index);
|
|
nl_add_attr_ipa(&r->h, rsize, RTA_GATEWAY, gw);
|
|
break;
|
|
case RTD_DEVICE:
|
|
r->r.rtm_type = RTN_UNICAST;
|
|
nl_add_attr_u32(&r->h, rsize, RTA_OIF, iface->index);
|
|
break;
|
|
case RTD_BLACKHOLE:
|
|
r->r.rtm_type = RTN_BLACKHOLE;
|
|
break;
|
|
case RTD_UNREACHABLE:
|
|
r->r.rtm_type = RTN_UNREACHABLE;
|
|
break;
|
|
case RTD_PROHIBIT:
|
|
r->r.rtm_type = RTN_PROHIBIT;
|
|
break;
|
|
case RTD_MULTIPATH:
|
|
r->r.rtm_type = RTN_UNICAST;
|
|
nl_add_multipath(&r->h, rsize, a->nexthops);
|
|
break;
|
|
case RTD_NONE:
|
|
break;
|
|
default:
|
|
bug("krt_capable inconsistent with nl_send_route");
|
|
}
|
|
|
|
/* Ignore missing for DELETE */
|
|
return nl_exchange(&r->h, (op == NL_OP_DELETE));
|
|
}
|
|
|
|
static inline int
|
|
nl_add_rte(struct krt_proto *p, rte *e, struct ea_list *eattrs)
|
|
{
|
|
rta *a = e->attrs;
|
|
int err = 0;
|
|
|
|
if (krt_ecmp6(p) && (a->dest == RTD_MULTIPATH))
|
|
{
|
|
struct mpnh *nh = a->nexthops;
|
|
|
|
err = nl_send_route(p, e, eattrs, NL_OP_ADD, RTD_ROUTER, nh->gw, nh->iface);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
for (nh = nh->next; nh; nh = nh->next)
|
|
err += nl_send_route(p, e, eattrs, NL_OP_APPEND, RTD_ROUTER, nh->gw, nh->iface);
|
|
|
|
return err;
|
|
}
|
|
|
|
return nl_send_route(p, e, eattrs, NL_OP_ADD, a->dest, a->gw, a->iface);
|
|
}
|
|
|
|
static inline int
|
|
nl_delete_rte(struct krt_proto *p, rte *e, struct ea_list *eattrs)
|
|
{
|
|
int err = 0;
|
|
|
|
/* For IPv6, we just repeatedly request DELETE until we get error */
|
|
do
|
|
err = nl_send_route(p, e, eattrs, NL_OP_DELETE, RTD_NONE, IPA_NONE, NULL);
|
|
while (krt_ecmp6(p) && !err);
|
|
|
|
return err;
|
|
}
|
|
|
|
void
|
|
krt_replace_rte(struct krt_proto *p, net *n, rte *new, rte *old, struct ea_list *eattrs)
|
|
{
|
|
int err = 0;
|
|
|
|
/*
|
|
* We could use NL_OP_REPLACE, but route replace on Linux has some problems:
|
|
*
|
|
* 1) Does not check for matching rtm_protocol
|
|
* 2) Has broken semantics for IPv6 ECMP
|
|
* 3) Crashes some kernel version when used for IPv6 ECMP
|
|
*
|
|
* So we use NL_OP_DELETE and then NL_OP_ADD. We also do not trust the old
|
|
* route value, so we do not try to optimize IPv6 ECMP reconfigurations.
|
|
*/
|
|
|
|
if (old)
|
|
nl_delete_rte(p, old, eattrs);
|
|
|
|
if (new)
|
|
err = nl_add_rte(p, new, eattrs);
|
|
|
|
if (err < 0)
|
|
n->n.flags |= KRF_SYNC_ERROR;
|
|
else
|
|
n->n.flags &= ~KRF_SYNC_ERROR;
|
|
}
|
|
|
|
|
|
static inline struct mpnh *
|
|
nl_alloc_mpnh(struct nl_parse_state *s, ip_addr gw, struct iface *iface, byte weight)
|
|
{
|
|
struct mpnh *nh = lp_alloc(s->pool, sizeof(struct mpnh));
|
|
|
|
nh->gw = gw;
|
|
nh->iface = iface;
|
|
nh->next = NULL;
|
|
nh->weight = weight;
|
|
|
|
return nh;
|
|
}
|
|
|
|
static int
|
|
nl_mergable_route(struct nl_parse_state *s, net *net, struct krt_proto *p, uint priority, uint krt_type)
|
|
{
|
|
/* Route merging must be active */
|
|
if (!s->merge)
|
|
return 0;
|
|
|
|
/* Saved and new route must have same network, proto/table, and priority */
|
|
if ((s->net != net) || (s->proto != p) || (s->krt_metric != priority))
|
|
return 0;
|
|
|
|
/* Both must be regular unicast routes */
|
|
if ((s->krt_type != RTN_UNICAST) || (krt_type != RTN_UNICAST))
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
|
|
static void
|
|
nl_announce_route(struct nl_parse_state *s)
|
|
{
|
|
rte *e = rte_get_temp(s->attrs);
|
|
e->net = s->net;
|
|
e->u.krt.src = s->krt_src;
|
|
e->u.krt.proto = s->krt_proto;
|
|
e->u.krt.seen = 0;
|
|
e->u.krt.best = 0;
|
|
e->u.krt.metric = s->krt_metric;
|
|
|
|
if (s->scan)
|
|
krt_got_route(s->proto, e);
|
|
else
|
|
krt_got_route_async(s->proto, e, s->new);
|
|
|
|
s->net = NULL;
|
|
s->attrs = NULL;
|
|
s->proto = NULL;
|
|
lp_flush(s->pool);
|
|
}
|
|
|
|
static inline void
|
|
nl_parse_begin(struct nl_parse_state *s, int scan, int merge)
|
|
{
|
|
memset(s, 0, sizeof (struct nl_parse_state));
|
|
s->pool = nl_linpool;
|
|
s->scan = scan;
|
|
s->merge = merge;
|
|
}
|
|
|
|
static inline void
|
|
nl_parse_end(struct nl_parse_state *s)
|
|
{
|
|
if (s->net)
|
|
nl_announce_route(s);
|
|
}
|
|
|
|
|
|
#define SKIP(ARG...) do { DBG("KRT: Ignoring route - " ARG); return; } while(0)
|
|
|
|
static void
|
|
nl_parse_route(struct nl_parse_state *s, struct nlmsghdr *h)
|
|
{
|
|
struct krt_proto *p;
|
|
struct rtmsg *i;
|
|
struct rtattr *a[BIRD_RTA_MAX];
|
|
int new = h->nlmsg_type == RTM_NEWROUTE;
|
|
|
|
ip_addr dst = IPA_NONE;
|
|
u32 oif = ~0;
|
|
u32 table;
|
|
u32 priority = 0;
|
|
u32 def_scope = RT_SCOPE_UNIVERSE;
|
|
int src;
|
|
|
|
if (!(i = nl_checkin(h, sizeof(*i))))
|
|
return;
|
|
|
|
switch (i->rtm_family)
|
|
{
|
|
#ifndef IPV6
|
|
case AF_INET:
|
|
if (!nl_parse_attrs(RTM_RTA(i), rtm_attr_want4, a, sizeof(a)))
|
|
return;
|
|
break;
|
|
#else
|
|
case AF_INET6:
|
|
if (!nl_parse_attrs(RTM_RTA(i), rtm_attr_want6, a, sizeof(a)))
|
|
return;
|
|
break;
|
|
#endif
|
|
default:
|
|
return;
|
|
}
|
|
|
|
if (a[RTA_DST])
|
|
{
|
|
memcpy(&dst, RTA_DATA(a[RTA_DST]), sizeof(dst));
|
|
ipa_ntoh(dst);
|
|
}
|
|
|
|
if (a[RTA_OIF])
|
|
oif = rta_get_u32(a[RTA_OIF]);
|
|
|
|
if (a[RTA_TABLE])
|
|
table = rta_get_u32(a[RTA_TABLE]);
|
|
else
|
|
table = i->rtm_table;
|
|
|
|
p = HASH_FIND(nl_table_map, RTH, table); /* Do we know this table? */
|
|
DBG("KRT: Got %I/%d, type=%d, oif=%d, table=%d, prid=%d, proto=%s\n", dst, i->rtm_dst_len, i->rtm_type, oif, table, i->rtm_protocol, p ? p->p.name : "(none)");
|
|
if (!p)
|
|
SKIP("unknown table %d\n", table);
|
|
|
|
#ifdef IPV6
|
|
if (a[RTA_IIF])
|
|
SKIP("IIF set\n");
|
|
#else
|
|
if (i->rtm_tos != 0) /* We don't support TOS */
|
|
SKIP("TOS %02x\n", i->rtm_tos);
|
|
#endif
|
|
|
|
if (s->scan && !new)
|
|
SKIP("RTM_DELROUTE in scan\n");
|
|
|
|
if (a[RTA_PRIORITY])
|
|
priority = rta_get_u32(a[RTA_PRIORITY]);
|
|
|
|
int c = ipa_classify_net(dst);
|
|
if ((c < 0) || !(c & IADDR_HOST) || ((c & IADDR_SCOPE_MASK) <= SCOPE_LINK))
|
|
SKIP("strange class/scope\n");
|
|
|
|
switch (i->rtm_protocol)
|
|
{
|
|
case RTPROT_UNSPEC:
|
|
SKIP("proto unspec\n");
|
|
|
|
case RTPROT_REDIRECT:
|
|
src = KRT_SRC_REDIRECT;
|
|
break;
|
|
|
|
case RTPROT_KERNEL:
|
|
src = KRT_SRC_KERNEL;
|
|
return;
|
|
|
|
case RTPROT_BIRD:
|
|
if (!s->scan)
|
|
SKIP("echo\n");
|
|
src = KRT_SRC_BIRD;
|
|
break;
|
|
|
|
case RTPROT_BOOT:
|
|
default:
|
|
src = KRT_SRC_ALIEN;
|
|
}
|
|
|
|
net *net = net_get(p->p.table, dst, i->rtm_dst_len);
|
|
|
|
if (s->net && !nl_mergable_route(s, net, p, priority, i->rtm_type))
|
|
nl_announce_route(s);
|
|
|
|
rta *ra = lp_allocz(s->pool, sizeof(rta));
|
|
ra->src = p->p.main_source;
|
|
ra->source = RTS_INHERIT;
|
|
ra->scope = SCOPE_UNIVERSE;
|
|
ra->cast = RTC_UNICAST;
|
|
|
|
switch (i->rtm_type)
|
|
{
|
|
case RTN_UNICAST:
|
|
|
|
if (a[RTA_MULTIPATH])
|
|
{
|
|
ra->dest = RTD_MULTIPATH;
|
|
ra->nexthops = nl_parse_multipath(p, a[RTA_MULTIPATH], i->rtm_family);
|
|
if (!ra->nexthops)
|
|
{
|
|
log(L_ERR "KRT: Received strange multipath route %I/%d",
|
|
net->n.prefix, net->n.pxlen);
|
|
return;
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
ra->iface = if_find_by_index(oif);
|
|
if (!ra->iface)
|
|
{
|
|
log(L_ERR "KRT: Received route %I/%d with unknown ifindex %u",
|
|
net->n.prefix, net->n.pxlen, oif);
|
|
return;
|
|
}
|
|
|
|
if (a[RTA_GATEWAY])
|
|
{
|
|
neighbor *ng;
|
|
ra->dest = RTD_ROUTER;
|
|
memcpy(&ra->gw, RTA_DATA(a[RTA_GATEWAY]), sizeof(ra->gw));
|
|
ipa_ntoh(ra->gw);
|
|
|
|
#ifdef IPV6
|
|
/* Silently skip strange 6to4 routes */
|
|
if (ipa_in_net(ra->gw, IPA_NONE, 96))
|
|
return;
|
|
#endif
|
|
|
|
ng = neigh_find2(&p->p, &ra->gw, ra->iface,
|
|
(i->rtm_flags & RTNH_F_ONLINK) ? NEF_ONLINK : 0);
|
|
if (!ng || (ng->scope == SCOPE_HOST))
|
|
{
|
|
log(L_ERR "KRT: Received route %I/%d with strange next-hop %I",
|
|
net->n.prefix, net->n.pxlen, ra->gw);
|
|
return;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
ra->dest = RTD_DEVICE;
|
|
def_scope = RT_SCOPE_LINK;
|
|
}
|
|
|
|
break;
|
|
case RTN_BLACKHOLE:
|
|
ra->dest = RTD_BLACKHOLE;
|
|
break;
|
|
case RTN_UNREACHABLE:
|
|
ra->dest = RTD_UNREACHABLE;
|
|
break;
|
|
case RTN_PROHIBIT:
|
|
ra->dest = RTD_PROHIBIT;
|
|
break;
|
|
/* FIXME: What about RTN_THROW? */
|
|
default:
|
|
SKIP("type %d\n", i->rtm_type);
|
|
return;
|
|
}
|
|
|
|
if (i->rtm_scope != def_scope)
|
|
{
|
|
ea_list *ea = lp_alloc(s->pool, sizeof(ea_list) + sizeof(eattr));
|
|
ea->next = ra->eattrs;
|
|
ra->eattrs = ea;
|
|
ea->flags = EALF_SORTED;
|
|
ea->count = 1;
|
|
ea->attrs[0].id = EA_KRT_SCOPE;
|
|
ea->attrs[0].flags = 0;
|
|
ea->attrs[0].type = EAF_TYPE_INT;
|
|
ea->attrs[0].u.data = i->rtm_scope;
|
|
}
|
|
|
|
if (a[RTA_PREFSRC])
|
|
{
|
|
ip_addr ps;
|
|
memcpy(&ps, RTA_DATA(a[RTA_PREFSRC]), sizeof(ps));
|
|
ipa_ntoh(ps);
|
|
|
|
ea_list *ea = lp_alloc(s->pool, sizeof(ea_list) + sizeof(eattr));
|
|
ea->next = ra->eattrs;
|
|
ra->eattrs = ea;
|
|
ea->flags = EALF_SORTED;
|
|
ea->count = 1;
|
|
ea->attrs[0].id = EA_KRT_PREFSRC;
|
|
ea->attrs[0].flags = 0;
|
|
ea->attrs[0].type = EAF_TYPE_IP_ADDRESS;
|
|
ea->attrs[0].u.ptr = lp_alloc(s->pool, sizeof(struct adata) + sizeof(ps));
|
|
ea->attrs[0].u.ptr->length = sizeof(ps);
|
|
memcpy(ea->attrs[0].u.ptr->data, &ps, sizeof(ps));
|
|
}
|
|
|
|
if (a[RTA_FLOW])
|
|
{
|
|
ea_list *ea = lp_alloc(s->pool, sizeof(ea_list) + sizeof(eattr));
|
|
ea->next = ra->eattrs;
|
|
ra->eattrs = ea;
|
|
ea->flags = EALF_SORTED;
|
|
ea->count = 1;
|
|
ea->attrs[0].id = EA_KRT_REALM;
|
|
ea->attrs[0].flags = 0;
|
|
ea->attrs[0].type = EAF_TYPE_INT;
|
|
ea->attrs[0].u.data = rta_get_u32(a[RTA_FLOW]);
|
|
}
|
|
|
|
if (a[RTA_METRICS])
|
|
{
|
|
u32 metrics[KRT_METRICS_MAX];
|
|
ea_list *ea = lp_alloc(s->pool, sizeof(ea_list) + KRT_METRICS_MAX * sizeof(eattr));
|
|
int t, n = 0;
|
|
|
|
if (nl_parse_metrics(a[RTA_METRICS], metrics, ARRAY_SIZE(metrics)) < 0)
|
|
{
|
|
log(L_ERR "KRT: Received route %I/%d with strange RTA_METRICS attribute",
|
|
net->n.prefix, net->n.pxlen);
|
|
return;
|
|
}
|
|
|
|
for (t = 1; t < KRT_METRICS_MAX; t++)
|
|
if (metrics[0] & (1 << t))
|
|
{
|
|
ea->attrs[n].id = EA_CODE(EAP_KRT, KRT_METRICS_OFFSET + t);
|
|
ea->attrs[n].flags = 0;
|
|
ea->attrs[n].type = EAF_TYPE_INT; /* FIXME: Some are EAF_TYPE_BITFIELD */
|
|
ea->attrs[n].u.data = metrics[t];
|
|
n++;
|
|
}
|
|
|
|
if (n > 0)
|
|
{
|
|
ea->next = ra->eattrs;
|
|
ea->flags = EALF_SORTED;
|
|
ea->count = n;
|
|
ra->eattrs = ea;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Ideally, now we would send the received route to the rest of kernel code.
|
|
* But IPv6 ECMP routes before 4.11 are sent as a sequence of routes, so we
|
|
* postpone it and merge next hops until the end of the sequence. Note that
|
|
* proper multipath updates are rejected by nl_mergable_route(), so it is
|
|
* always the first case for them.
|
|
*/
|
|
|
|
if (!s->net)
|
|
{
|
|
/* Store the new route */
|
|
s->net = net;
|
|
s->attrs = ra;
|
|
s->proto = p;
|
|
s->new = new;
|
|
s->krt_src = src;
|
|
s->krt_type = i->rtm_type;
|
|
s->krt_proto = i->rtm_protocol;
|
|
s->krt_metric = priority;
|
|
}
|
|
else
|
|
{
|
|
/* Merge next hops with the stored route */
|
|
rta *a = s->attrs;
|
|
|
|
if (a->dest != RTD_MULTIPATH)
|
|
{
|
|
a->dest = RTD_MULTIPATH;
|
|
a->nexthops = nl_alloc_mpnh(s, a->gw, a->iface, 0);
|
|
}
|
|
|
|
mpnh_insert(&a->nexthops, nl_alloc_mpnh(s, ra->gw, ra->iface, 0));
|
|
}
|
|
}
|
|
|
|
void
|
|
krt_do_scan(struct krt_proto *p UNUSED) /* CONFIG_ALL_TABLES_AT_ONCE => p is NULL */
|
|
{
|
|
struct nlmsghdr *h;
|
|
struct nl_parse_state s;
|
|
|
|
nl_parse_begin(&s, 1, krt_ecmp6(p));
|
|
|
|
nl_request_dump(BIRD_AF, RTM_GETROUTE);
|
|
while (h = nl_get_scan())
|
|
if (h->nlmsg_type == RTM_NEWROUTE || h->nlmsg_type == RTM_DELROUTE)
|
|
nl_parse_route(&s, h);
|
|
else
|
|
log(L_DEBUG "nl_scan_fire: Unknown packet received (type=%d)", h->nlmsg_type);
|
|
|
|
nl_parse_end(&s);
|
|
}
|
|
|
|
/*
|
|
* Asynchronous Netlink interface
|
|
*/
|
|
|
|
static sock *nl_async_sk; /* BIRD socket for asynchronous notifications */
|
|
static byte *nl_async_rx_buffer; /* Receive buffer */
|
|
|
|
static void
|
|
nl_async_msg(struct nlmsghdr *h)
|
|
{
|
|
struct nl_parse_state s;
|
|
|
|
switch (h->nlmsg_type)
|
|
{
|
|
case RTM_NEWROUTE:
|
|
case RTM_DELROUTE:
|
|
DBG("KRT: Received async route notification (%d)\n", h->nlmsg_type);
|
|
nl_parse_begin(&s, 0, 0);
|
|
nl_parse_route(&s, h);
|
|
nl_parse_end(&s);
|
|
break;
|
|
case RTM_NEWLINK:
|
|
case RTM_DELLINK:
|
|
DBG("KRT: Received async link notification (%d)\n", h->nlmsg_type);
|
|
if (kif_proto)
|
|
nl_parse_link(h, 0);
|
|
break;
|
|
case RTM_NEWADDR:
|
|
case RTM_DELADDR:
|
|
DBG("KRT: Received async address notification (%d)\n", h->nlmsg_type);
|
|
if (kif_proto)
|
|
nl_parse_addr(h, 0);
|
|
break;
|
|
default:
|
|
DBG("KRT: Received unknown async notification (%d)\n", h->nlmsg_type);
|
|
}
|
|
}
|
|
|
|
static int
|
|
nl_async_hook(sock *sk, uint size UNUSED)
|
|
{
|
|
struct iovec iov = { nl_async_rx_buffer, NL_RX_SIZE };
|
|
struct sockaddr_nl sa;
|
|
struct msghdr m = {
|
|
.msg_name = &sa,
|
|
.msg_namelen = sizeof(sa),
|
|
.msg_iov = &iov,
|
|
.msg_iovlen = 1,
|
|
};
|
|
struct nlmsghdr *h;
|
|
int x;
|
|
uint len;
|
|
|
|
x = recvmsg(sk->fd, &m, 0);
|
|
if (x < 0)
|
|
{
|
|
if (errno == ENOBUFS)
|
|
{
|
|
/*
|
|
* Netlink reports some packets have been thrown away.
|
|
* One day we might react to it by asking for route table
|
|
* scan in near future.
|
|
*/
|
|
log(L_WARN "Kernel dropped some netlink messages, will resync on next scan.");
|
|
return 1; /* More data are likely to be ready */
|
|
}
|
|
else if (errno != EWOULDBLOCK)
|
|
log(L_ERR "Netlink recvmsg: %m");
|
|
return 0;
|
|
}
|
|
if (sa.nl_pid) /* It isn't from the kernel */
|
|
{
|
|
DBG("Non-kernel packet\n");
|
|
return 1;
|
|
}
|
|
h = (void *) nl_async_rx_buffer;
|
|
len = x;
|
|
if (m.msg_flags & MSG_TRUNC)
|
|
{
|
|
log(L_WARN "Netlink got truncated asynchronous message");
|
|
return 1;
|
|
}
|
|
while (NLMSG_OK(h, len))
|
|
{
|
|
nl_async_msg(h);
|
|
h = NLMSG_NEXT(h, len);
|
|
}
|
|
if (len)
|
|
log(L_WARN "nl_async_hook: Found packet remnant of size %d", len);
|
|
return 1;
|
|
}
|
|
|
|
static void
|
|
nl_async_err_hook(sock *sk, int e UNUSED)
|
|
{
|
|
nl_async_hook(sk, 0);
|
|
}
|
|
|
|
static void
|
|
nl_open_async(void)
|
|
{
|
|
sock *sk;
|
|
struct sockaddr_nl sa;
|
|
int fd;
|
|
|
|
if (nl_async_sk)
|
|
return;
|
|
|
|
DBG("KRT: Opening async netlink socket\n");
|
|
|
|
fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
|
|
if (fd < 0)
|
|
{
|
|
log(L_ERR "Unable to open asynchronous rtnetlink socket: %m");
|
|
return;
|
|
}
|
|
|
|
bzero(&sa, sizeof(sa));
|
|
sa.nl_family = AF_NETLINK;
|
|
#ifdef IPV6
|
|
sa.nl_groups = RTMGRP_LINK | RTMGRP_IPV6_IFADDR | RTMGRP_IPV6_ROUTE;
|
|
#else
|
|
sa.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR | RTMGRP_IPV4_ROUTE;
|
|
#endif
|
|
if (bind(fd, (struct sockaddr *) &sa, sizeof(sa)) < 0)
|
|
{
|
|
log(L_ERR "Unable to bind asynchronous rtnetlink socket: %m");
|
|
close(fd);
|
|
return;
|
|
}
|
|
|
|
nl_async_rx_buffer = xmalloc(NL_RX_SIZE);
|
|
|
|
sk = nl_async_sk = sk_new(krt_pool);
|
|
sk->type = SK_MAGIC;
|
|
sk->rx_hook = nl_async_hook;
|
|
sk->err_hook = nl_async_err_hook;
|
|
sk->fd = fd;
|
|
if (sk_open(sk) < 0)
|
|
bug("Netlink: sk_open failed");
|
|
}
|
|
|
|
|
|
/*
|
|
* Interface to the UNIX krt module
|
|
*/
|
|
|
|
void
|
|
krt_sys_io_init(void)
|
|
{
|
|
nl_linpool = lp_new(krt_pool, 4080);
|
|
HASH_INIT(nl_table_map, krt_pool, 6);
|
|
}
|
|
|
|
int
|
|
krt_sys_start(struct krt_proto *p)
|
|
{
|
|
struct krt_proto *old = HASH_FIND(nl_table_map, RTH, krt_table_id(p));
|
|
|
|
if (old)
|
|
{
|
|
log(L_ERR "%s: Kernel table %u already registered by %s",
|
|
p->p.name, krt_table_id(p), old->p.name);
|
|
return 0;
|
|
}
|
|
|
|
HASH_INSERT2(nl_table_map, RTH, krt_pool, p);
|
|
|
|
nl_open();
|
|
nl_open_async();
|
|
|
|
return 1;
|
|
}
|
|
|
|
void
|
|
krt_sys_shutdown(struct krt_proto *p)
|
|
{
|
|
HASH_REMOVE2(nl_table_map, RTH, krt_pool, p);
|
|
}
|
|
|
|
int
|
|
krt_sys_reconfigure(struct krt_proto *p UNUSED, struct krt_config *n, struct krt_config *o)
|
|
{
|
|
return (n->sys.table_id == o->sys.table_id) && (n->sys.metric == o->sys.metric);
|
|
}
|
|
|
|
void
|
|
krt_sys_init_config(struct krt_config *cf)
|
|
{
|
|
cf->sys.table_id = RT_TABLE_MAIN;
|
|
cf->sys.metric = 0;
|
|
}
|
|
|
|
void
|
|
krt_sys_copy_config(struct krt_config *d, struct krt_config *s)
|
|
{
|
|
d->sys.table_id = s->sys.table_id;
|
|
d->sys.metric = s->sys.metric;
|
|
}
|
|
|
|
static const char *krt_metrics_names[KRT_METRICS_MAX] = {
|
|
NULL, "lock", "mtu", "window", "rtt", "rttvar", "sstresh", "cwnd", "advmss",
|
|
"reordering", "hoplimit", "initcwnd", "features", "rto_min", "initrwnd", "quickack"
|
|
};
|
|
|
|
static const char *krt_features_names[KRT_FEATURES_MAX] = {
|
|
"ecn", NULL, NULL, "allfrag"
|
|
};
|
|
|
|
int
|
|
krt_sys_get_attr(eattr *a, byte *buf, int buflen UNUSED)
|
|
{
|
|
switch (a->id)
|
|
{
|
|
case EA_KRT_PREFSRC:
|
|
bsprintf(buf, "prefsrc");
|
|
return GA_NAME;
|
|
|
|
case EA_KRT_REALM:
|
|
bsprintf(buf, "realm");
|
|
return GA_NAME;
|
|
|
|
case EA_KRT_SCOPE:
|
|
bsprintf(buf, "scope");
|
|
return GA_NAME;
|
|
|
|
case EA_KRT_LOCK:
|
|
buf += bsprintf(buf, "lock:");
|
|
ea_format_bitfield(a, buf, buflen, krt_metrics_names, 2, KRT_METRICS_MAX);
|
|
return GA_FULL;
|
|
|
|
case EA_KRT_FEATURES:
|
|
buf += bsprintf(buf, "features:");
|
|
ea_format_bitfield(a, buf, buflen, krt_features_names, 0, KRT_FEATURES_MAX);
|
|
return GA_FULL;
|
|
|
|
default:;
|
|
int id = (int)EA_ID(a->id) - KRT_METRICS_OFFSET;
|
|
if (id > 0 && id < KRT_METRICS_MAX)
|
|
{
|
|
bsprintf(buf, "%s", krt_metrics_names[id]);
|
|
return GA_NAME;
|
|
}
|
|
|
|
return GA_UNKNOWN;
|
|
}
|
|
}
|
|
|
|
|
|
|
|
void
|
|
kif_sys_start(struct kif_proto *p UNUSED)
|
|
{
|
|
nl_open();
|
|
nl_open_async();
|
|
}
|
|
|
|
void
|
|
kif_sys_shutdown(struct kif_proto *p UNUSED)
|
|
{
|
|
} |