Skip to content
Navigation Menu
{{ message }}
forked from jserv/nstack
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathnstack.c
More file actions
382 lines (312 loc) · 9.15 KB
/
Copy pathnstack.c
File metadata and controls
382 lines (312 loc) · 9.15 KB
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
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
#define _GNU_SOURCE
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <unistd.h>
#include "linker_set.h"
#include "nstack_in.h"
#include "nstack_socket.h"
#include "collection.h"
#include "logger.h"
#include "nstack_ether.h"
#include "nstack_internal.h"
#include "nstack_ip.h"
#include "tcp.h"
#include "udp.h"
/**
* nstack ingress and egress thread state.
*/
enum nstack_state {
NSTACK_STOPPED = 0, /*!< Ingress and egress threads are not running. */
NSTACK_RUNNING, /*!< Ingress and egress threads are running. */
NSTACK_DYING, /*!< Waiting for ingress and engress threads to stop. */
};
SET_DECLARE(_nstack_periodic_tasks, void);
/*
* nstack state variables.
*/
static enum nstack_state nstack_state = NSTACK_STOPPED;
static pthread_t ingress_tid, egress_tid;
static int ether_handle;
static nstack_send_fn *proto_send[] = {
[XIP_PROTO_TCP] = nstack_tcp_send,
[XIP_PROTO_UDP] = nstack_udp_send,
};
static struct nstack_sock sockets[] = {
{
.info.sock_dom = XF_INET4,
.info.sock_type = XSOCK_DGRAM,
.info.sock_proto = XIP_PROTO_UDP,
.info.sock_addr =
(struct nstack_sockaddr){
.inet4_addr = 167772162,
.port = 10,
},
.shmem_path = "/tmp/unetcat.sock",
},
{.info.sock_dom = XF_INET4,
.info.sock_type = XSOCK_STREAM,
.info.sock_proto = XIP_PROTO_TCP,
.info.sock_addr =
(struct nstack_sockaddr){
.inet4_addr = 167772162,
.port = 10,
},
.shmem_path = "/tmp/tnetcat.sock"},
};
static enum nstack_state get_state(void)
{
enum nstack_state *state = &nstack_state;
return *state;
}
static void set_state(enum nstack_state state)
{
nstack_state = state;
}
static int delta_time;
static int eval_timer(void)
{
static struct timespec start;
struct timespec now;
clock_gettime(CLOCK_MONOTONIC, &now);
delta_time = now.tv_sec - start.tv_sec;
if (delta_time >= NSTACK_PERIODIC_EVENT_SEC) {
start = now;
return !0;
}
return 0;
}
/**
* Bind an address to a socket.
* @param[in] sock is a pointer to the socket returned by nstack_socket().
* @returns Uppon succesful completion returns 0;
* Otherwise -1 is returned and errno is set.
*/
static int nstack_bind(struct nstack_sock *sock)
{
switch (sock->info.sock_proto) {
case XIP_PROTO_UDP:
return nstack_udp_bind(sock);
case XIP_PROTO_TCP:
return nstack_tcp_bind(sock);
default:
errno = EPROTOTYPE;
return -1;
}
}
int nstack_sock_dgram_input(struct nstack_sock *sock,
struct nstack_sockaddr *srcaddr,
uint8_t *buf,
size_t bsize)
{
int dgram_index;
struct nstack_dgram *dgram;
while ((dgram_index = queue_alloc(sock->ingress_q)) == -1)
;
dgram = (struct nstack_dgram *) (sock->ingress_data + dgram_index);
dgram->srcaddr = *srcaddr;
dgram->dstaddr = sock->info.sock_addr;
dgram->buf_size = bsize;
memcpy(dgram->buf, buf, bsize);
queue_commit(sock->ingress_q);
kill(sock->ctrl->pid_end, SIGUSR2);
return 0;
}
static void run_periodic_tasks(int delta_time)
{
void **taskp;
SET_FOREACH (taskp, _nstack_periodic_tasks) {
nstack_periodic_task_t *task = *(nstack_periodic_task_t **) taskp;
if (task)
task(delta_time);
}
}
/**
* Handle the ingress traffic.
* All ingress data is handled in a single pipeline until this point where
* the data is demultiplexed to sockets.
* transport -> socket fd
*/
static void *nstack_ingress_thread(void *arg)
{
static uint8_t rx_buffer[ETHER_MAXLEN];
while (1) {
struct ether_hdr hdr;
int retval;
LOG(LOG_DEBUG, "Waiting for rx");
retval =
ether_receive(ether_handle, &hdr, rx_buffer, sizeof(rx_buffer));
if (retval == -1) {
LOG(LOG_ERR, "Rx failed: %d", errno);
} else if (retval > 0) {
LOG(LOG_DEBUG, "Frame received!");
retval = ether_input(&hdr, rx_buffer, retval);
if (retval == -1) {
LOG(LOG_ERR, "Protocol handling failed: %d", errno);
} else if (retval > 0) {
retval =
ether_output_reply(ether_handle, &hdr, rx_buffer, retval);
if (retval < 0) {
LOG(LOG_ERR, "Reply failed: %d", errno);
}
}
}
if (eval_timer()) {
LOG(LOG_DEBUG, "tick");
run_periodic_tasks(delta_time);
}
if (get_state() == NSTACK_DYING) {
break;
}
}
pthread_exit(NULL);
}
/**
* Handle the egress traffic.
* All egress traffic is mux'd and serialized through one egress pipe.
* socket fd -> transport
*/
static void *nstack_egress_thread(void *arg)
{
sigset_t sigset;
sigemptyset(&sigset);
sigaddset(&sigset, SIGUSR2);
if (pthread_sigmask(SIG_BLOCK, &sigset, NULL) == -1) {
LOG(LOG_ERR, "Unable to ignore SIGUSR2");
abort();
}
while (1) {
struct timespec timeout = {
.tv_sec = NSTACK_PERIODIC_EVENT_SEC,
.tv_nsec = 0,
};
sigtimedwait(&sigset, NULL, &timeout);
for (size_t i = 0; i < num_elem(sockets); i++) {
struct nstack_sock *sock = sockets + i;
if (!queue_isempty(sock->egress_q)) {
int dgram_index;
struct nstack_dgram *dgram;
enum nstack_sock_proto proto;
while (!queue_peek(sock->egress_q, &dgram_index))
;
dgram =
(struct nstack_dgram *) (sock->egress_data + dgram_index);
LOG(LOG_DEBUG, "Sending a datagram");
proto = sock->info.sock_proto;
if (proto > XIP_PROTO_NONE && proto < XIP_PROTO_LAST) {
if (proto_send[proto](sock, dgram) < 0) {
LOG(LOG_ERR, "Failed to send a datagram");
}
} else {
LOG(LOG_ERR, "Invalid protocol");
}
queue_discard(sock->egress_q, 1);
}
}
if (get_state() == NSTACK_DYING)
break;
}
pthread_exit(NULL);
}
static void nstack_init(void)
{
pid_t mypid = getpid();
for (size_t i = 0; i < num_elem(sockets); i++) {
struct nstack_sock *sock = sockets + i;
int fd;
void *pa;
fd = open(sock->shmem_path, O_RDWR);
if (fd == -1) {
perror("Failed to open shmem file");
exit(1);
}
pa = mmap(0, NSTACK_SHMEM_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
0);
if (pa == MAP_FAILED) {
perror("Failed to mmap() shared mem");
exit(1);
}
memset(pa, 0, NSTACK_SHMEM_SIZE);
sock->ctrl = NSTACK_SOCK_CTRL(pa);
*sock->ctrl = (struct nstack_sock_ctrl){
.pid_inetd = mypid,
.pid_end = 0,
};
sock->ingress_data = NSTACK_INGRESS_DADDR(pa);
sock->ingress_q = NSTACK_INGRESS_QADDR(pa);
*sock->ingress_q =
queue_create(NSTACK_DATAGRAM_SIZE_MAX, NSTACK_DATAGRAM_BUF_SIZE);
sock->egress_data = NSTACK_EGRESS_DADDR(pa);
sock->egress_q = NSTACK_EGRESS_QADDR(pa);
*sock->egress_q =
queue_create(NSTACK_DATAGRAM_SIZE_MAX, NSTACK_DATAGRAM_BUF_SIZE);
if (nstack_bind(sock) < 0) {
perror("Failed to bind a socket");
exit(1);
}
}
}
int nstack_start(int handle)
{
ether_handle = handle;
if (get_state() != NSTACK_STOPPED) {
errno = EALREADY;
return -1;
}
nstack_init();
if (pthread_create(&ingress_tid, NULL, nstack_ingress_thread, NULL)) {
return -1;
}
if (pthread_create(&egress_tid, NULL, nstack_egress_thread, NULL)) {
pthread_cancel(ingress_tid);
return -1;
}
set_state(NSTACK_RUNNING);
return 0;
}
void nstack_stop(void)
{
set_state(NSTACK_DYING);
pthread_join(ingress_tid, NULL);
pthread_join(egress_tid, NULL);
set_state(NSTACK_STOPPED);
}
int main(int argc, char *argv[])
{
char *const ether_args[] = {
argv[1],
NULL,
};
int handle;
sigset_t sigset;
if (argc == 1) {
fprintf(stderr, "Usage: %s INTERFACE\n", argv[0]);
exit(1);
}
sigemptyset(&sigset);
sigaddset(&sigset, SIGUSR1);
/* Block sigset for all future threads */
sigprocmask(SIG_SETMASK, &sigset, NULL);
handle = ether_init(ether_args);
if (handle == -1) {
perror("Failed to init");
exit(1);
} else if (handle == -2) {
perror("Interface identifier is too long");
exit(1);
}
if (ip_config(handle, STACK_IP, SUBNET_MASK)) {
perror("Failed to config IP");
exit(1);
}
nstack_start(handle);
sigwaitinfo(&sigset, NULL);
fprintf(stderr, "Stopping the IP stack...\n");
nstack_stop();
ether_deinit(handle);
return 0;
}
You can’t perform that action at this time.