1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * ucon.c |
4 | * |
5 | * Copyright (c) 2004+ Evgeniy Polyakov <zbr@ioremap.net> |
6 | */ |
7 | |
8 | #include <asm/types.h> |
9 | |
10 | #include <sys/types.h> |
11 | #include <sys/socket.h> |
12 | #include <sys/poll.h> |
13 | |
14 | #include <linux/netlink.h> |
15 | #include <linux/rtnetlink.h> |
16 | |
17 | #include <arpa/inet.h> |
18 | |
19 | #include <stdbool.h> |
20 | #include <stdio.h> |
21 | #include <stdlib.h> |
22 | #include <unistd.h> |
23 | #include <string.h> |
24 | #include <errno.h> |
25 | #include <time.h> |
26 | #include <getopt.h> |
27 | |
28 | #include <linux/connector.h> |
29 | |
30 | #define DEBUG |
31 | #define NETLINK_CONNECTOR 11 |
32 | |
33 | /* Hopefully your userspace connector.h matches this kernel */ |
34 | #define CN_TEST_IDX CN_NETLINK_USERS + 3 |
35 | #define CN_TEST_VAL 0x456 |
36 | |
37 | #ifdef DEBUG |
38 | #define ulog(f, a...) fprintf(stdout, f, ##a) |
39 | #else |
40 | #define ulog(f, a...) do {} while (0) |
41 | #endif |
42 | |
43 | static int need_exit; |
44 | static __u32 seq; |
45 | |
46 | static int netlink_send(int s, struct cn_msg *msg) |
47 | { |
48 | struct nlmsghdr *nlh; |
49 | unsigned int size; |
50 | int err; |
51 | char buf[128]; |
52 | struct cn_msg *m; |
53 | |
54 | size = NLMSG_SPACE(sizeof(struct cn_msg) + msg->len); |
55 | |
56 | nlh = (struct nlmsghdr *)buf; |
57 | nlh->nlmsg_seq = seq++; |
58 | nlh->nlmsg_pid = getpid(); |
59 | nlh->nlmsg_type = NLMSG_DONE; |
60 | nlh->nlmsg_len = size; |
61 | nlh->nlmsg_flags = 0; |
62 | |
63 | m = NLMSG_DATA(nlh); |
64 | #if 0 |
65 | ulog("%s: [%08x.%08x] len=%u, seq=%u, ack=%u.\n" , |
66 | __func__, msg->id.idx, msg->id.val, msg->len, msg->seq, msg->ack); |
67 | #endif |
68 | memcpy(dest: m, src: msg, n: sizeof(*m) + msg->len); |
69 | |
70 | err = send(fd: s, buf: nlh, n: size, flags: 0); |
71 | if (err == -1) |
72 | ulog("Failed to send: %s [%d].\n" , |
73 | strerror(errno), errno); |
74 | |
75 | return err; |
76 | } |
77 | |
78 | static void usage(void) |
79 | { |
80 | printf( |
81 | format: "Usage: ucon [options] [output file]\n" |
82 | "\n" |
83 | "\t-h\tthis help screen\n" |
84 | "\t-s\tsend buffers to the test module\n" |
85 | "\n" |
86 | "The default behavior of ucon is to subscribe to the test module\n" |
87 | "and wait for state messages. Any ones received are dumped to the\n" |
88 | "specified output file (or stdout). The test module is assumed to\n" |
89 | "have an id of {%u.%u}\n" |
90 | "\n" |
91 | "If you get no output, then verify the cn_test module id matches\n" |
92 | "the expected id above.\n" |
93 | , CN_TEST_IDX, CN_TEST_VAL |
94 | ); |
95 | } |
96 | |
97 | int main(int argc, char *argv[]) |
98 | { |
99 | int s; |
100 | char buf[1024]; |
101 | int len; |
102 | struct nlmsghdr *reply; |
103 | struct sockaddr_nl l_local; |
104 | struct cn_msg *data; |
105 | FILE *out; |
106 | time_t tm; |
107 | struct pollfd pfd; |
108 | bool send_msgs = false; |
109 | |
110 | while ((s = getopt(argc: argc, argv: argv, shortopts: "hs" )) != -1) { |
111 | switch (s) { |
112 | case 's': |
113 | send_msgs = true; |
114 | break; |
115 | |
116 | case 'h': |
117 | usage(); |
118 | return 0; |
119 | |
120 | default: |
121 | /* getopt() outputs an error for us */ |
122 | usage(); |
123 | return 1; |
124 | } |
125 | } |
126 | |
127 | if (argc != optind) { |
128 | out = fopen(filename: argv[optind], modes: "a+" ); |
129 | if (!out) { |
130 | ulog("Unable to open %s for writing: %s\n" , |
131 | argv[1], strerror(errno)); |
132 | out = stdout; |
133 | } |
134 | } else |
135 | out = stdout; |
136 | |
137 | memset(s: buf, c: 0, n: sizeof(buf)); |
138 | |
139 | s = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR); |
140 | if (s == -1) { |
141 | perror(s: "socket" ); |
142 | return -1; |
143 | } |
144 | |
145 | l_local.nl_family = AF_NETLINK; |
146 | l_local.nl_groups = -1; /* bitmask of requested groups */ |
147 | l_local.nl_pid = 0; |
148 | |
149 | ulog("subscribing to %u.%u\n" , CN_TEST_IDX, CN_TEST_VAL); |
150 | |
151 | if (bind(fd: s, addr: (struct sockaddr *)&l_local, len: sizeof(struct sockaddr_nl)) == -1) { |
152 | perror(s: "bind" ); |
153 | close(fd: s); |
154 | return -1; |
155 | } |
156 | |
157 | #if 0 |
158 | { |
159 | int on = 0x57; /* Additional group number */ |
160 | setsockopt(s, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &on, sizeof(on)); |
161 | } |
162 | #endif |
163 | if (send_msgs) { |
164 | int i, j; |
165 | |
166 | memset(s: buf, c: 0, n: sizeof(buf)); |
167 | |
168 | data = (struct cn_msg *)buf; |
169 | |
170 | data->id.idx = CN_TEST_IDX; |
171 | data->id.val = CN_TEST_VAL; |
172 | data->seq = seq++; |
173 | data->ack = 0; |
174 | data->len = 0; |
175 | |
176 | for (j=0; j<10; ++j) { |
177 | for (i=0; i<1000; ++i) { |
178 | len = netlink_send(s, msg: data); |
179 | } |
180 | |
181 | ulog("%d messages have been sent to %08x.%08x.\n" , i, data->id.idx, data->id.val); |
182 | } |
183 | |
184 | return 0; |
185 | } |
186 | |
187 | |
188 | pfd.fd = s; |
189 | |
190 | while (!need_exit) { |
191 | pfd.events = POLLIN; |
192 | pfd.revents = 0; |
193 | switch (poll(fds: &pfd, nfds: 1, timeout: -1)) { |
194 | case 0: |
195 | need_exit = 1; |
196 | break; |
197 | case -1: |
198 | if (errno != EINTR) { |
199 | need_exit = 1; |
200 | break; |
201 | } |
202 | continue; |
203 | } |
204 | if (need_exit) |
205 | break; |
206 | |
207 | memset(s: buf, c: 0, n: sizeof(buf)); |
208 | len = recv(fd: s, buf: buf, n: sizeof(buf), flags: 0); |
209 | if (len == -1) { |
210 | perror(s: "recv buf" ); |
211 | close(fd: s); |
212 | return -1; |
213 | } |
214 | reply = (struct nlmsghdr *)buf; |
215 | |
216 | switch (reply->nlmsg_type) { |
217 | case NLMSG_ERROR: |
218 | fprintf(stream: out, format: "Error message received.\n" ); |
219 | fflush(stream: out); |
220 | break; |
221 | case NLMSG_DONE: |
222 | data = (struct cn_msg *)NLMSG_DATA(reply); |
223 | |
224 | time(timer: &tm); |
225 | fprintf(stream: out, format: "%.24s : [%x.%x] [%08u.%08u].\n" , |
226 | ctime(timer: &tm), data->id.idx, data->id.val, data->seq, data->ack); |
227 | fflush(stream: out); |
228 | break; |
229 | default: |
230 | break; |
231 | } |
232 | } |
233 | |
234 | close(fd: s); |
235 | return 0; |
236 | } |
237 | |