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
|
// vim:ts=8:expandtab
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdbool.h>
#include <unistd.h>
#include <stdlib.h>
#include <netdb.h>
#include <string.h>
#include <yajl/yajl_gen.h>
#include <yajl/yajl_version.h>
#include "i3status.h"
static char *get_sockname(struct addrinfo *addr) {
static char buf[INET6_ADDRSTRLEN+1];
struct sockaddr_storage local;
int ret;
int fd;
if ((fd = socket(addr->ai_family, SOCK_DGRAM, 0)) == -1) {
perror("socket()");
return NULL;
}
/* Since the socket was created with SOCK_DGRAM, this is
* actually not establishing a connection or generating
* any other network traffic. Instead, as a side-effect,
* it saves the local address with which packets would
* be sent to the destination. */
if (connect(fd, addr->ai_addr, addr->ai_addrlen) == -1) {
/* We don’t display the error here because most
* likely, there just is no IPv6 connectivity.
* Thus, don’t spam the user’s console but just
* try the next address. */
(void)close(fd);
return NULL;
}
socklen_t local_len = sizeof(struct sockaddr_storage);
if (getsockname(fd, (struct sockaddr*)&local, &local_len) == -1) {
perror("getsockname()");
(void)close(fd);
return NULL;
}
memset(buf, 0, INET6_ADDRSTRLEN + 1);
if ((ret = getnameinfo((struct sockaddr*)&local, local_len,
buf, sizeof(buf), NULL, 0,
NI_NUMERICHOST)) != 0) {
fprintf(stderr, "i3status: getnameinfo(): %s\n", gai_strerror(ret));
(void)close(fd);
return NULL;
}
(void)close(fd);
return buf;
}
/*
* Returns the IPv6 address with which you have connectivity at the moment.
* The char * is statically allocated and mustn't be freed
*/
static char *get_ipv6_addr(void) {
struct addrinfo hints;
struct addrinfo *result, *resp;
static struct addrinfo *cached = NULL;
/* To save dns lookups (if they are not cached locally) and creating
* sockets, we save the fd and keep it open. */
if (cached != NULL)
return get_sockname(cached);
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = AF_INET6;
hints.ai_socktype = SOCK_DGRAM;
/* We use the public IPv6 of the K root server here. It doesn’t matter
* which IPv6 address we use (we don’t even send any packets), as long
* as it’s considered global by the kernel.
* NB: We don’t use a hostname since that would trigger a DNS lookup.
* By using an IPv6 address, getaddrinfo() will *not* do a DNS lookup,
* but return the address in the appropriate struct. */
if (getaddrinfo("2001:7fd::1", "domain", &hints, &result) != 0) {
/* We don’t display the error here because most
* likely, there just is no connectivity.
* Thus, don’t spam the user’s console. */
return NULL;
}
for (resp = result; resp != NULL; resp = resp->ai_next) {
char *addr_string = get_sockname(resp);
/* If we could not get our own address and there is more than
* one result for resolving k.root-servers.net, we cannot
* cache. Otherwise, no matter if we got IPv6 connectivity or
* not, we will cache the (single) result and are done. */
if (!addr_string && result->ai_next != NULL)
continue;
if ((cached = malloc(sizeof(struct addrinfo))) == NULL)
return NULL;
memcpy(cached, resp, sizeof(struct addrinfo));
if ((cached->ai_addr = malloc(resp->ai_addrlen)) == NULL) {
cached = NULL;
return NULL;
}
memcpy(cached->ai_addr, resp->ai_addr, resp->ai_addrlen);
freeaddrinfo(result);
return addr_string;
}
freeaddrinfo(result);
return NULL;
}
void print_ipv6_info(yajl_gen json_gen, char *buffer, const char *format_up, const char *format_down) {
const char *walk;
char *addr_string = get_ipv6_addr();
char *outwalk = buffer;
if (addr_string == NULL) {
START_COLOR("color_bad");
outwalk += sprintf(outwalk, "%s", format_down);
END_COLOR;
OUTPUT_FULL_TEXT(buffer);
return;
}
START_COLOR("color_good");
for (walk = format_up; *walk != '\0'; walk++) {
if (*walk != '%') {
*(outwalk++) = *walk;
continue;
}
if (strncmp(walk+1, "ip", strlen("ip")) == 0) {
outwalk += sprintf(outwalk, "%s", addr_string);
walk += strlen("ip");
}
}
END_COLOR;
OUTPUT_FULL_TEXT(buffer);
}
|
