1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
// SPDX-License-Identifier: GPL-2.0-or-later
/* NHRP netlink/neighbor table arpd code
* Copyright (c) 2014-2016 Timo Teräs
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <fcntl.h>
#include <net/if.h>
#include <netinet/if_ether.h>
#include <linux/netlink.h>
#include <linux/neighbour.h>
#include <linux/netfilter/nfnetlink_log.h>
#include "frrevent.h"
#include "stream.h"
#include "prefix.h"
#include "nhrpd.h"
#include "netlink.h"
#include "znl.h"
int netlink_nflog_group;
static int netlink_log_fd = -1;
static struct event *netlink_log_thread;
void netlink_update_binding(struct interface *ifp, union sockunion *proto,
union sockunion *nbma)
{
nhrp_send_zebra_nbr(proto, nbma, ifp);
}
static void netlink_log_register(int fd, int group)
{
struct nlmsghdr *n;
struct nfgenmsg *nf;
struct nfulnl_msg_config_cmd cmd;
struct zbuf *zb = zbuf_alloc(512);
n = znl_nlmsg_push(zb, (NFNL_SUBSYS_ULOG << 8) | NFULNL_MSG_CONFIG,
NLM_F_REQUEST | NLM_F_ACK);
nf = znl_push(zb, sizeof(*nf));
*nf = (struct nfgenmsg){
.nfgen_family = AF_UNSPEC,
.version = NFNETLINK_V0,
.res_id = htons(group),
};
cmd.command = NFULNL_CFG_CMD_BIND;
znl_rta_push(zb, NFULA_CFG_CMD, &cmd, sizeof(cmd));
znl_nlmsg_complete(zb, n);
zbuf_send(zb, fd);
zbuf_free(zb);
}
static void netlink_log_indication(struct nlmsghdr *msg, struct zbuf *zb)
{
struct nfgenmsg *nf;
struct rtattr *rta;
struct zbuf rtapl, pktpl;
struct interface *ifp;
struct nfulnl_msg_packet_hdr *pkthdr = NULL;
uint32_t *in_ndx = NULL;
nf = znl_pull(zb, sizeof(*nf));
if (!nf)
return;
memset(&pktpl, 0, sizeof(pktpl));
while ((rta = znl_rta_pull(zb, &rtapl)) != NULL) {
switch (rta->rta_type) {
case NFULA_PACKET_HDR:
pkthdr = znl_pull(&rtapl, sizeof(*pkthdr));
break;
case NFULA_IFINDEX_INDEV:
in_ndx = znl_pull(&rtapl, sizeof(*in_ndx));
break;
case NFULA_PAYLOAD:
pktpl = rtapl;
break;
/* NFULA_HWHDR exists and is supposed to contain source
* hardware address. However, for ip_gre it seems to be
* the nexthop destination address if the packet matches
* route. */
}
}
if (!pkthdr || !in_ndx || !zbuf_used(&pktpl))
return;
ifp = if_lookup_by_index(htonl(*in_ndx), VRF_DEFAULT);
if (!ifp)
return;
nhrp_peer_send_indication(ifp, htons(pkthdr->hw_protocol), &pktpl);
}
static void netlink_log_recv(struct event *t)
{
uint8_t buf[ZNL_BUFFER_SIZE];
int fd = EVENT_FD(t);
struct zbuf payload, zb;
struct nlmsghdr *n;
zbuf_init(&zb, buf, sizeof(buf), 0);
while (zbuf_recv(&zb, fd) > 0) {
while ((n = znl_nlmsg_pull(&zb, &payload)) != NULL) {
debugf(NHRP_DEBUG_KERNEL,
"Netlink-log: Received msg_type %u, msg_flags %u",
n->nlmsg_type, n->nlmsg_flags);
switch (n->nlmsg_type) {
case (NFNL_SUBSYS_ULOG << 8) | NFULNL_MSG_PACKET:
netlink_log_indication(n, &payload);
break;
}
}
}
event_add_read(master, netlink_log_recv, 0, netlink_log_fd,
&netlink_log_thread);
}
void netlink_set_nflog_group(int nlgroup)
{
if (netlink_log_fd >= 0) {
event_cancel(&netlink_log_thread);
close(netlink_log_fd);
netlink_log_fd = -1;
}
netlink_nflog_group = nlgroup;
if (nlgroup) {
netlink_log_fd = znl_open(NETLINK_NETFILTER, 0);
if (netlink_log_fd < 0)
return;
netlink_log_register(netlink_log_fd, nlgroup);
event_add_read(master, netlink_log_recv, 0, netlink_log_fd,
&netlink_log_thread);
}
}
int nhrp_neighbor_operation(ZAPI_CALLBACK_ARGS)
{
union sockunion addr = {}, lladdr = {};
struct interface *ifp;
int state, ndm_state;
struct nhrp_cache *c;
struct zapi_neigh_ip api = {};
zclient_neigh_ip_decode(zclient->ibuf, &api);
if (api.ip_in.ipa_type == AF_UNSPEC)
return 0;
sockunion_family(&addr) = api.ip_in.ipa_type;
memcpy((uint8_t *)sockunion_get_addr(&addr), &api.ip_in.ip.addr,
family2addrsize(api.ip_in.ipa_type));
sockunion_family(&lladdr) = api.ip_out.ipa_type;
if (api.ip_out.ipa_type != AF_UNSPEC)
memcpy((uint8_t *)sockunion_get_addr(&lladdr),
&api.ip_out.ip.addr,
family2addrsize(api.ip_out.ipa_type));
ifp = if_lookup_by_index(api.index, vrf_id);
ndm_state = api.ndm_state;
if (!ifp)
return 0;
c = nhrp_cache_get(ifp, &addr, 0);
if (!c)
return 0;
debugf(NHRP_DEBUG_KERNEL,
"Netlink: %s %pSU dev %s lladdr %pSU nud 0x%x cache used %u type %u",
(cmd == ZEBRA_NHRP_NEIGH_GET)
? "who-has"
: (cmd == ZEBRA_NHRP_NEIGH_ADDED) ? "new-neigh"
: "del-neigh",
&addr, ifp->name, &lladdr, ndm_state, c->used, c->cur.type);
if (cmd == ZEBRA_NHRP_NEIGH_GET) {
if (c->cur.type >= NHRP_CACHE_CACHED) {
nhrp_cache_set_used(c, 1);
debugf(NHRP_DEBUG_KERNEL,
"Netlink: update binding for %pSU dev %s from c %pSU peer.vc.nbma %pSU to lladdr %pSU",
&addr, ifp->name, &c->cur.remote_nbma_natoa,
&c->cur.peer->vc->remote.nbma, &lladdr);
/* In case of shortcuts, nbma is given by lladdr, not
* vc->remote.nbma.
*/
netlink_update_binding(ifp, &addr, &lladdr);
}
} else {
state = (cmd == ZEBRA_NHRP_NEIGH_ADDED) ? ndm_state
: ZEBRA_NEIGH_STATE_FAILED;
nhrp_cache_set_used(c, state == ZEBRA_NEIGH_STATE_REACHABLE);
}
return 0;
}
|
