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
|
/* This example is placed in the public domain. */
#include <netinet/in.h>
#include <arpa/inet.h>
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <strings.h>
#include <net/if.h>
#include <libmnl/libmnl.h>
#include <linux/if_link.h>
#include <linux/rtnetlink.h>
int main(int argc, char *argv[])
{
struct mnl_socket *nl;
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *nlh;
struct ifaddrmsg *ifm;
uint32_t seq, portid;
union {
in_addr_t ip;
struct in6_addr ip6;
} addr;
int ret, family = AF_INET;
uint32_t prefix;
int iface;
if (argc <= 3) {
printf("Usage: %s iface destination cidr\n", argv[0]);
printf("Example: %s eth0 10.0.1.12 32\n", argv[0]);
printf(" %s eth0 ffff::10.0.1.12 128\n", argv[0]);
exit(EXIT_FAILURE);
}
iface = if_nametoindex(argv[1]);
if (iface == 0) {
perror("if_nametoindex");
exit(EXIT_FAILURE);
}
if (!inet_pton(AF_INET, argv[2], &addr)) {
if (!inet_pton(AF_INET6, argv[2], &addr)) {
perror("inet_pton");
exit(EXIT_FAILURE);
}
family = AF_INET6;
}
if (sscanf(argv[3], "%u", &prefix) == 0) {
perror("sscanf");
exit(EXIT_FAILURE);
}
nlh = mnl_nlmsg_put_header(buf);
nlh->nlmsg_type = RTM_NEWADDR;
nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_ACK;
nlh->nlmsg_seq = seq = time(NULL);
ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(struct ifaddrmsg));
ifm->ifa_family = family;
ifm->ifa_prefixlen = prefix;
ifm->ifa_flags = IFA_F_PERMANENT;
ifm->ifa_scope = RT_SCOPE_UNIVERSE;
ifm->ifa_index = iface;
/*
* The exact meaning of IFA_LOCAL and IFA_ADDRESS depend
* on the address family being used and the device type.
* For broadcast devices (like the interfaces we use),
* for IPv4 we specify both and they are used interchangeably.
* For IPv6, only IFA_ADDRESS needs to be set.
*/
if (family == AF_INET) {
mnl_attr_put_u32(nlh, IFA_LOCAL, addr.ip);
mnl_attr_put_u32(nlh, IFA_ADDRESS, addr.ip);
} else {
mnl_attr_put(nlh, IFA_ADDRESS, sizeof(struct in6_addr), &addr);
}
nl = mnl_socket_open(NETLINK_ROUTE);
if (nl == NULL) {
perror("mnl_socket_open");
exit(EXIT_FAILURE);
}
if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
perror("mnl_socket_bind");
exit(EXIT_FAILURE);
}
portid = mnl_socket_get_portid(nl);
if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
perror("mnl_socket_sendto");
exit(EXIT_FAILURE);
}
ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
if (ret < 0) {
perror("mnl_socket_recvfrom");
exit(EXIT_FAILURE);
}
ret = mnl_cb_run(buf, ret, seq, portid, NULL, NULL);
if (ret < 0) {
perror("mnl_cb_run");
exit(EXIT_FAILURE);
}
mnl_socket_close(nl);
return 0;
}
|
