1 /* When dealing with SLIP (to a pty, or ipif) we have separate rx, tx
2 and client buffers. When receiving we may read() any amount, not
3 just whole packets. When transmitting we need to bytestuff anyway,
4 and may be part-way through receiving. */
18 #define SLIP_ESCEND 220
19 #define SLIP_ESCESC 221
23 struct buffer_if *buff; /* We unstuff received packets into here
24 and send them to the netlink code. */
26 netlink_deliver_fn *netlink_to_tunnel;
27 uint32_t local_address;
30 /* Generic SLIP mangling code */
32 static void slip_stuff(struct slip *st, struct buffer_if *buf, int fd)
34 uint8_t txbuf[DEFAULT_BUFSIZE];
40 /* XXX crunchy bytestuff code */
42 for (i=buf->start; i<(buf->start+buf->size); i++) {
46 txbuf[j++]=SLIP_ESCEND;
50 txbuf[j++]=SLIP_ESCESC;
56 if ((j+2)>DEFAULT_BUFSIZE) {
57 if (write(fd,txbuf,j)<0) {
58 fatal_perror("slip_stuff: write()");
64 if (write(fd,txbuf,j)<0) {
65 fatal_perror("slip_stuff: write()");
70 static void slip_unstuff(struct slip *st, uint8_t *buf, uint32_t l)
74 /* XXX really crude unstuff code */
75 /* XXX check for buffer overflow */
76 BUF_ASSERT_USED(st->buff);
78 if (st->pending_esc) {
79 st->pending_esc=False;
82 *(uint8_t *)buf_append(st->buff,1)=SLIP_END;
85 *(uint8_t *)buf_append(st->buff,1)=SLIP_ESC;
88 fatal("userv_afterpoll: bad SLIP escape character\n");
93 if (st->buff->size>0) {
94 st->netlink_to_tunnel(&st->nl,st->buff);
95 BUF_ALLOC(st->buff,"userv_afterpoll");
97 buffer_init(st->buff,st->nl.max_start_pad);
100 st->pending_esc=True;
103 *(uint8_t *)buf_append(st->buff,1)=buf[i];
110 static void slip_init(struct slip *st, struct cloc loc, dict_t *dict,
111 string_t name, netlink_deliver_fn *to_host)
113 st->netlink_to_tunnel=
114 netlink_init(&st->nl,st,loc,dict,
115 "netlink-userv-ipif",NULL,to_host);
116 st->buff=find_cl_if(dict,"buffer",CL_BUFFER,True,"name",loc);
117 st->local_address=string_item_to_ipaddr(
118 dict_find_item(dict,"local-address", True, name, loc),"netlink");
119 BUF_ALLOC(st->buff,"slip_init");
120 st->pending_esc=False;
123 /* Connection to the kernel through userv-ipif */
127 int txfd; /* We transmit to userv */
128 int rxfd; /* We receive from userv */
130 string_t service_user;
131 string_t service_name;
133 bool_t expecting_userv_exit;
136 static int userv_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
137 int *timeout_io, const struct timeval *tv_now,
140 struct userv *st=sst;
145 fds[0].events=POLLERR; /* Might want to pick up POLLOUT sometime */
147 fds[1].events=POLLIN|POLLERR|POLLHUP;
154 static void userv_afterpoll(void *sst, struct pollfd *fds, int nfds,
155 const struct timeval *tv_now, uint64_t *now)
157 struct userv *st=sst;
158 uint8_t rxbuf[DEFAULT_BUFSIZE];
163 if (fds[1].revents&POLLERR) {
164 Message(M_ERR,"%s: userv_afterpoll: POLLERR!\n",st->slip.nl.name);
166 if (fds[1].revents&POLLIN) {
167 l=read(st->rxfd,rxbuf,DEFAULT_BUFSIZE);
170 fatal_perror("%s: userv_afterpoll: read(rxfd)",
173 fatal("%s: userv_afterpoll: read(rxfd)=0; userv gone away?\n",
175 } else slip_unstuff(&st->slip,rxbuf,l);
179 /* Send buf to the kernel. Free buf before returning. */
180 static void userv_deliver_to_kernel(void *sst, struct buffer_if *buf)
182 struct userv *st=sst;
184 slip_stuff(&st->slip,buf,st->txfd);
187 static void userv_userv_callback(void *sst, pid_t pid, int status)
189 struct userv *st=sst;
192 Message(M_WARNING,"userv_callback called unexpectedly with pid %d "
193 "(expected %d)\n",pid,st->pid);
196 if (!st->expecting_userv_exit) {
197 if (WIFEXITED(status)) {
198 fatal("%s: userv exited unexpectedly with status %d\n",
199 st->slip.nl.name,WEXITSTATUS(status));
200 } else if (WIFSIGNALED(status)) {
201 fatal("%s: userv exited unexpectedly: uncaught signal %d\n",
202 st->slip.nl.name,WTERMSIG(status));
204 fatal("%s: userv stopped unexpectedly\n");
207 Message(M_WARNING,"%s: userv subprocess died with status %d\n",
208 st->slip.nl.name,WEXITSTATUS(status));
212 struct userv_entry_rec {
217 /* XXX perhaps we should collect and log stderr? */
220 static void userv_entry(void *sst)
222 struct userv_entry_rec *st=sst;
227 /* XXX close all other fds */
229 execvp(st->path,st->argv);
230 perror("userv-entry: execvp()");
234 static void userv_invoke_userv(struct userv *st)
236 struct userv_entry_rec *er;
242 struct netlink_route *r;
243 struct ipset *isnets;
244 struct subnet_list *snets;
249 fatal("userv_invoke_userv: already running\n");
252 /* This is where we actually invoke userv - all the networks we'll
253 be using should already have been registered. */
255 addrs=safe_malloc(512,"userv_invoke_userv:addrs");
256 snprintf(addrs,512,"%s,%s,%d,slip",
257 ipaddr_to_string(st->slip.local_address),
258 ipaddr_to_string(st->slip.nl.secnet_address),st->slip.nl.mtu);
260 r=st->slip.nl.routes;
262 for (i=0; i<st->slip.nl.n_routes; i++) {
264 struct ipset *sn,*nis;
266 sn=ipset_from_subnet(r[i].net);
267 nis=ipset_union(isnets,sn);
273 snets=ipset_to_subnet_list(isnets);
275 nets=safe_malloc(20*snets->entries,"userv_invoke_userv:nets");
277 for (i=0; i<snets->entries; i++) {
278 s=subnet_to_string(snets->list[i]);
283 nets[strlen(nets)-1]=0;
284 subnet_list_free(snets);
286 Message(M_INFO,"%s: about to invoke: %s %s %s %s %s\n",st->slip.nl.name,
287 st->userv_path,st->service_user,st->service_name,addrs,nets);
289 st->slip.pending_esc=False;
292 if (pipe(c_stdin)!=0) {
293 fatal_perror("userv_invoke_userv: pipe(c_stdin)");
295 if (pipe(c_stdout)!=0) {
296 fatal_perror("userv_invoke_userv: pipe(c_stdout)");
299 st->rxfd=c_stdout[0];
301 er=safe_malloc(sizeof(*r),"userv_invoke_userv: er");
305 /* The arguments are:
309 local-addr,secnet-addr,mtu,protocol
311 er->argv=safe_malloc(sizeof(*er->argv)*6,"userv_invoke_userv:argv");
312 er->argv[0]=st->userv_path;
313 er->argv[1]=st->service_user;
314 er->argv[2]=st->service_name;
318 er->path=st->userv_path;
320 st->pid=makesubproc(userv_entry, userv_userv_callback,
321 er, st, st->slip.nl.name);
328 Message(M_INFO,"%s: userv-ipif pid is %d\n",st->slip.nl.name,st->pid);
329 /* Read a single character from the pipe to confirm userv-ipif is
330 running. If we get a SIGCHLD at this point then we'll get EINTR. */
331 if (read(st->rxfd,&confirm,1)!=1) {
333 Message(M_WARNING,"%s: read of confirmation byte was "
334 "interrupted\n",st->slip.nl.name);
336 fatal_perror("%s: read() of confirmation byte",st->slip.nl.name);
339 if (confirm!=SLIP_END) {
340 fatal("%s: bad confirmation byte %d from userv-ipif\n",
341 st->slip.nl.name,confirm);
344 /* Mark rxfd non-blocking */
345 if (fcntl(st->rxfd, F_SETFL, fcntl(st->rxfd, F_GETFL)|O_NONBLOCK)==-1) {
346 fatal_perror("%s: fcntl(O_NONBLOCK)",st->slip.nl.name);
350 static void userv_kill_userv(struct userv *st)
353 kill(-st->pid,SIGTERM);
354 st->expecting_userv_exit=True;
358 static void userv_phase_hook(void *sst, uint32_t newphase)
360 struct userv *st=sst;
361 /* We must wait until signal processing has started before forking
363 if (newphase==PHASE_RUN) {
364 userv_invoke_userv(st);
365 /* Register for poll() */
366 register_for_poll(st, userv_beforepoll, userv_afterpoll, 2,
369 if (newphase==PHASE_SHUTDOWN) {
370 userv_kill_userv(st);
374 static list_t *userv_apply(closure_t *self, struct cloc loc, dict_t *context,
381 st=safe_malloc(sizeof(*st),"userv_apply");
383 /* First parameter must be a dict */
384 item=list_elem(args,0);
385 if (!item || item->type!=t_dict)
386 cfgfatal(loc,"userv-ipif","parameter must be a dictionary\n");
388 dict=item->data.dict;
390 slip_init(&st->slip,loc,dict,"netlink-userv-ipif",
391 userv_deliver_to_kernel);
393 st->userv_path=dict_read_string(dict,"userv-path",False,"userv-netlink",
395 st->service_user=dict_read_string(dict,"service-user",False,
396 "userv-netlink",loc);
397 st->service_name=dict_read_string(dict,"service-name",False,
398 "userv-netlink",loc);
399 if (!st->userv_path) st->userv_path="userv";
400 if (!st->service_user) st->service_user="root";
401 if (!st->service_name) st->service_name="ipif";
402 st->rxfd=-1; st->txfd=-1;
404 st->expecting_userv_exit=False;
405 add_hook(PHASE_RUN,userv_phase_hook,st);
406 add_hook(PHASE_SHUTDOWN,userv_phase_hook,st);
408 return new_closure(&st->slip.nl.cl);
411 init_module slip_module;
412 void slip_module(dict_t *dict)
414 add_closure(dict,"userv-ipif",userv_apply);
417 add_closure(dict,"pty-slip",ptyslip_apply);
418 add_closure(dict,"slipd",slipd_apply);