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 /* There's probably a much more efficient way of implementing this */
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 BUF_ASSERT_USED(st->buff);
76 if (st->pending_esc) {
77 st->pending_esc=False;
80 *(uint8_t *)buf_append(st->buff,1)=SLIP_END;
83 *(uint8_t *)buf_append(st->buff,1)=SLIP_ESC;
86 fatal("userv_afterpoll: bad SLIP escape character");
91 if (st->buff->size>0) {
92 st->netlink_to_tunnel(&st->nl,st->buff);
93 BUF_ALLOC(st->buff,"userv_afterpoll");
95 buffer_init(st->buff,st->nl.max_start_pad);
101 *(uint8_t *)buf_append(st->buff,1)=buf[i];
108 static void slip_init(struct slip *st, struct cloc loc, dict_t *dict,
109 cstring_t name, netlink_deliver_fn *to_host)
111 st->netlink_to_tunnel=
112 netlink_init(&st->nl,st,loc,dict,
113 "netlink-userv-ipif",NULL,to_host);
114 st->buff=find_cl_if(dict,"buffer",CL_BUFFER,True,"name",loc);
115 st->local_address=string_item_to_ipaddr(
116 dict_find_item(dict,"local-address", True, name, loc),"netlink");
117 BUF_ALLOC(st->buff,"slip_init");
118 st->pending_esc=False;
121 /* Connection to the kernel through userv-ipif */
125 int txfd; /* We transmit to userv */
126 int rxfd; /* We receive from userv */
127 cstring_t userv_path;
128 cstring_t service_user;
129 cstring_t service_name;
131 bool_t expecting_userv_exit;
134 static int userv_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
135 int *timeout_io, const struct timeval *tv_now,
138 struct userv *st=sst;
143 fds[0].events=0; /* Might want to pick up POLLOUT sometime */
145 fds[1].events=POLLIN;
152 static void userv_afterpoll(void *sst, struct pollfd *fds, int nfds,
153 const struct timeval *tv_now, uint64_t *now)
155 struct userv *st=sst;
156 uint8_t rxbuf[DEFAULT_BUFSIZE];
161 if (fds[1].revents&POLLERR) {
162 Message(M_ERR,"%s: userv_afterpoll: POLLERR!\n",st->slip.nl.name);
164 if (fds[1].revents&POLLIN) {
165 l=read(st->rxfd,rxbuf,DEFAULT_BUFSIZE);
168 fatal_perror("%s: userv_afterpoll: read(rxfd)",
171 fatal("%s: userv_afterpoll: read(rxfd)=0; userv gone away?",
173 } else slip_unstuff(&st->slip,rxbuf,l);
177 /* Send buf to the kernel. Free buf before returning. */
178 static void userv_deliver_to_kernel(void *sst, struct buffer_if *buf)
180 struct userv *st=sst;
182 slip_stuff(&st->slip,buf,st->txfd);
185 static void userv_userv_callback(void *sst, pid_t pid, int status)
187 struct userv *st=sst;
190 Message(M_WARNING,"userv_callback called unexpectedly with pid %d "
191 "(expected %d)\n",pid,st->pid);
194 if (!st->expecting_userv_exit) {
195 if (WIFEXITED(status)) {
196 fatal("%s: userv exited unexpectedly with status %d",
197 st->slip.nl.name,WEXITSTATUS(status));
198 } else if (WIFSIGNALED(status)) {
199 fatal("%s: userv exited unexpectedly: uncaught signal %d",
200 st->slip.nl.name,WTERMSIG(status));
202 fatal("%s: userv stopped unexpectedly");
205 Message(M_WARNING,"%s: userv subprocess died with status %d\n",
206 st->slip.nl.name,WEXITSTATUS(status));
210 struct userv_entry_rec {
215 /* XXX perhaps we should collect and log stderr? */
218 static void userv_entry(void *sst)
220 struct userv_entry_rec *st=sst;
225 /* XXX close all other fds */
227 /* XXX We really should strdup() all of argv[] but because we'll just
228 exit anyway if execvp() fails it doesn't seem worth bothering. */
229 execvp(st->path,(char *const*)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_client *r;
243 struct ipset *allnets;
244 struct subnet_list *snets;
249 fatal("userv_invoke_userv: already running");
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);
261 for (r=st->slip.nl.clients; r; r=r->next) {
265 nan=ipset_union(allnets,r->networks);
270 snets=ipset_to_subnet_list(allnets);
272 nets=safe_malloc(20*snets->entries,"userv_invoke_userv:nets");
274 for (i=0; i<snets->entries; i++) {
275 s=subnet_to_string(snets->list[i]);
280 nets[strlen(nets)-1]=0;
281 subnet_list_free(snets);
283 Message(M_INFO,"%s: about to invoke: %s %s %s %s %s\n",st->slip.nl.name,
284 st->userv_path,st->service_user,st->service_name,addrs,nets);
286 st->slip.pending_esc=False;
289 if (pipe(c_stdin)!=0) {
290 fatal_perror("userv_invoke_userv: pipe(c_stdin)");
292 if (pipe(c_stdout)!=0) {
293 fatal_perror("userv_invoke_userv: pipe(c_stdout)");
296 st->rxfd=c_stdout[0];
298 er=safe_malloc(sizeof(*r),"userv_invoke_userv: er");
302 /* The arguments are:
306 local-addr,secnet-addr,mtu,protocol
308 er->argv=safe_malloc(sizeof(*er->argv)*6,"userv_invoke_userv:argv");
309 er->argv[0]=st->userv_path;
310 er->argv[1]=st->service_user;
311 er->argv[2]=st->service_name;
315 er->path=st->userv_path;
317 st->pid=makesubproc(userv_entry, userv_userv_callback,
318 er, st, st->slip.nl.name);
325 Message(M_INFO,"%s: userv-ipif pid is %d\n",st->slip.nl.name,st->pid);
326 /* Read a single character from the pipe to confirm userv-ipif is
327 running. If we get a SIGCHLD at this point then we'll get EINTR. */
328 if ((nread=read(st->rxfd,&confirm,1))!=1) {
330 Message(M_WARNING,"%s: read of confirmation byte was "
331 "interrupted\n",st->slip.nl.name);
334 fatal_perror("%s: error reading confirmation byte",
337 fatal("%s: unexpected EOF instead of confirmation byte"
338 " - userv ipif failed?", st->slip.nl.name);
342 if (confirm!=SLIP_END) {
343 fatal("%s: bad confirmation byte %d from userv-ipif",
344 st->slip.nl.name,confirm);
349 static void userv_kill_userv(struct userv *st)
352 kill(-st->pid,SIGTERM);
353 st->expecting_userv_exit=True;
357 static void userv_phase_hook(void *sst, uint32_t newphase)
359 struct userv *st=sst;
360 /* We must wait until signal processing has started before forking
362 if (newphase==PHASE_RUN) {
363 userv_invoke_userv(st);
364 /* Register for poll() */
365 register_for_poll(st, userv_beforepoll, userv_afterpoll, 2,
368 if (newphase==PHASE_SHUTDOWN) {
369 userv_kill_userv(st);
373 static list_t *userv_apply(closure_t *self, struct cloc loc, dict_t *context,
380 st=safe_malloc(sizeof(*st),"userv_apply");
382 /* First parameter must be a dict */
383 item=list_elem(args,0);
384 if (!item || item->type!=t_dict)
385 cfgfatal(loc,"userv-ipif","parameter must be a dictionary\n");
387 dict=item->data.dict;
389 slip_init(&st->slip,loc,dict,"netlink-userv-ipif",
390 userv_deliver_to_kernel);
392 st->userv_path=dict_read_string(dict,"userv-path",False,"userv-netlink",
394 st->service_user=dict_read_string(dict,"service-user",False,
395 "userv-netlink",loc);
396 st->service_name=dict_read_string(dict,"service-name",False,
397 "userv-netlink",loc);
398 if (!st->userv_path) st->userv_path="userv";
399 if (!st->service_user) st->service_user="root";
400 if (!st->service_name) st->service_name="ipif";
401 st->rxfd=-1; st->txfd=-1;
403 st->expecting_userv_exit=False;
404 add_hook(PHASE_RUN,userv_phase_hook,st);
405 add_hook(PHASE_SHUTDOWN,userv_phase_hook,st);
407 return new_closure(&st->slip.nl.cl);
410 void slip_module(dict_t *dict)
412 add_closure(dict,"userv-ipif",userv_apply);