1c1a9fa1 |
1 | /* |
2 | * userv service (or standalone program) |
3 | * for per-user IP subranges. |
4 | * |
5 | * This is invoked as root, directly from userv. |
6 | * Its arguments are supposed to be, in order: |
1e963473 |
7 | * <config> |
8 | * Specifies address ranges and gids which own them. |
1c1a9fa1 |
9 | * -- Indicates that the remaining arguments are user-supplied |
10 | * and therefore untrusted. |
11 | * <local-addr>,<peer-addr>,<mtu>,<proto> |
12 | * As for slattach. Supported protocols are slip, cslip, and |
13 | * adaptive. Alternatively, set to `debug' to print debugging |
14 | * info. <local-addr> is address of the interface on chiark; |
15 | * <peer-addr> is the address of the point-to-point peer. |
16 | * <prefix>/<mask>,<prefix>/<mask>,... |
17 | * List of additional routes to add for this interface. |
18 | * May be the empty argument. |
19 | * |
1e963473 |
20 | * <config> is either |
21 | * <gid>,<prefix>/<len>[,<junk>] |
22 | * indicating that that gid may allocate addresses in |
23 | * the relevant subspace (<junk> is ignored) |
24 | * or #... |
25 | * which is a comment |
26 | * or /<config-file-name> or ./<config-file-name> or ../<config-file-name> |
27 | * which refers to a file which contains lines which |
28 | * are each <config> |
29 | * or * |
30 | * which means that anything is permitted |
31 | * |
1c1a9fa1 |
32 | * Should be run from userv with no-disconnect-hup. |
33 | */ |
34 | |
35 | #include <stdio.h> |
36 | #include <string.h> |
37 | #include <stdlib.h> |
38 | #include <assert.h> |
39 | #include <errno.h> |
1e963473 |
40 | #include <stdarg.h> |
41 | #include <ctype.h> |
42 | #include <limits.h> |
02b2392d |
43 | #include <signal.h> |
44 | #include <unistd.h> |
45 | |
46 | #include <sys/types.h> |
47 | #include <sys/wait.h> |
48 | #include <sys/stat.h> |
1c1a9fa1 |
49 | |
1e963473 |
50 | #define NARGS 4 |
1c1a9fa1 |
51 | #define MAXEXROUTES 5 |
52 | #define ATXTLEN 12 |
53 | |
1e963473 |
54 | static const unsigned long gidmaxval= (unsigned long)((gid_t)-2); |
55 | static const char *const protos_ok[]= { "slip", "cslip", "adaptive", 0 }; |
02b2392d |
56 | static const int signals[]= { SIGHUP, SIGINT, SIGTERM, 0 }; |
1e963473 |
57 | |
58 | static const char *configstr, *proto; |
1c1a9fa1 |
59 | static unsigned long localaddr, peeraddr, mtu; |
1e963473 |
60 | static int localallow, peerallow, allallow; |
1c1a9fa1 |
61 | static int nexroutes; |
62 | static struct exroute { |
63 | unsigned long prefix, mask; |
1e963473 |
64 | int allow; |
1c1a9fa1 |
65 | char prefixtxt[ATXTLEN], masktxt[ATXTLEN]; |
66 | } exroutes[MAXEXROUTES]; |
67 | |
1e963473 |
68 | static char localtxt[ATXTLEN]; |
69 | static char peertxt[ATXTLEN]; |
70 | |
71 | static struct pplace { |
72 | struct pplace *parent; |
73 | const char *filename; |
74 | int lineno; |
75 | } *cpplace; |
76 | |
02b2392d |
77 | |
78 | static int slpipe[2], ptmaster; |
79 | static const char *ifname; |
80 | static const char *ptyname; |
81 | |
82 | #define NPIDS 4 |
83 | |
84 | static union { |
85 | struct { pid_t sl, cout, cin, task; } byname; |
86 | pid_t bynumber[NPIDS]; |
87 | } pids; |
88 | sigset_t emptyset, fullset; |
89 | |
90 | |
91 | static void terminate(int estatus) { |
92 | int i, status; |
93 | pid_t pid; |
94 | |
95 | for (i=0; i<NPIDS; i++) |
96 | if (pids.bynumber[i]) kill(pids.bynumber[i], SIGTERM); |
97 | |
98 | for (;;) { |
99 | pid= waitpid(-1,&status,0); |
100 | if (pid == (pid_t)-1) break; |
101 | } |
102 | exit(estatus); |
103 | } |
104 | |
105 | |
1e963473 |
106 | static void fatal(const char *fmt, ...) |
107 | __attribute__((format(printf,1,2))); |
108 | static void fatal(const char *fmt, ...) { |
109 | va_list al; |
110 | va_start(al,fmt); |
1c1a9fa1 |
111 | |
1e963473 |
112 | fputs("userv-ipif service: fatal error: ",stderr); |
113 | vfprintf(stderr, fmt, al); |
114 | putc('\n',stderr); |
02b2392d |
115 | terminate(8); |
1c1a9fa1 |
116 | } |
117 | |
1e963473 |
118 | static void sysfatal(const char *fmt, ...) |
119 | __attribute__((format(printf,1,2))); |
120 | static void sysfatal(const char *fmt, ...) { |
121 | va_list al; |
122 | int e; |
123 | |
124 | e= errno; |
125 | va_start(al,fmt); |
126 | |
127 | fputs("userv-ipif service: fatal system error",stderr); |
128 | vfprintf(stderr, fmt, al); |
129 | fprintf(stderr,"%s\n", strerror(e)); |
02b2392d |
130 | terminate(12); |
1c1a9fa1 |
131 | } |
1e963473 |
132 | |
133 | |
134 | static void badusage(const char *fmt, ...) |
135 | __attribute__((format(printf,1,2))); |
136 | static void badusage(const char *fmt, ...) { |
137 | va_list al; |
138 | struct pplace *cpp; |
1c1a9fa1 |
139 | |
1e963473 |
140 | if (cpplace) { |
141 | fprintf(stderr, |
142 | "userv-ipif service: %s:%d: ", |
143 | cpplace->filename, cpplace->lineno); |
144 | } else { |
145 | fputs("userv-ipif service: invalid usage: ",stderr); |
146 | } |
147 | va_start(al,fmt); |
148 | vfprintf(stderr, fmt, al); |
149 | putc('\n',stderr); |
150 | |
151 | if (cpplace) { |
152 | for (cpp=cpplace->parent; cpp; cpp=cpp->parent) { |
153 | fprintf(stderr, |
154 | "userv-ipif service: %s:%d: ... in file included from here\n", |
155 | cpp->filename, cpp->lineno); |
156 | } |
157 | } |
02b2392d |
158 | terminate(16); |
1c1a9fa1 |
159 | } |
160 | |
161 | static char *ip2txt(unsigned long addr, char *buf) { |
162 | sprintf(buf, "%lu.%lu.%lu.%lu", |
163 | (addr>>24) & 0x0ff, |
164 | (addr>>16) & 0x0ff, |
165 | (addr>>8) & 0x0ff, |
166 | (addr) & 0x0ff); |
167 | return buf; |
168 | } |
169 | |
170 | static unsigned long eat_number(const char **argp, const char *what, |
171 | unsigned long min, unsigned long max, |
172 | const char *endchars, int *endchar_r) { |
173 | /* If !endchars then the endchar must be a nul, otherwise it may be |
174 | * a nul (resulting in *argp set to 0) or something else (*argp set |
175 | * to point to after delim, *endchar_r set to delim). |
176 | * *endchar_r may be 0. |
177 | */ |
178 | unsigned long rv; |
179 | char *ep; |
180 | int endchar; |
181 | |
1e963473 |
182 | if (!*argp) { badusage("missing number %s\n",what); } |
1c1a9fa1 |
183 | rv= strtoul(*argp,&ep,0); |
184 | if ((endchar= *ep)) { |
1e963473 |
185 | if (!endchars) badusage("junk after number %s\n",what); |
186 | if (!strchr(endchars,endchar)) |
187 | badusage("invalid character or delimiter `%c' in or after number, %s:" |
188 | " expected %s (or none?)\n", endchar,what,endchars); |
1c1a9fa1 |
189 | *argp= ep+1; |
190 | } else { |
191 | *argp= 0; |
192 | } |
193 | if (endchar_r) *endchar_r= endchar; |
1e963473 |
194 | if (rv < min || rv > max) badusage("number %s value %lu out of range %lu..%lu", |
195 | what, rv, min, max); |
1c1a9fa1 |
196 | return rv; |
197 | } |
198 | |
1c1a9fa1 |
199 | static void addrnet_mustdiffer(const char *w1, unsigned long p1, unsigned long m1, |
200 | const char *w2, unsigned long p2, unsigned long m2) { |
201 | unsigned long mask; |
202 | |
203 | mask= m1&m2; |
204 | if ((p1 & mask) != (p2 & mask)) return; |
1e963473 |
205 | badusage("%s %08lx/%08lx overlaps/clashes with %s %08lx/%08lx", |
206 | w1,p1,m1, w2,p2,m2); |
1c1a9fa1 |
207 | } |
208 | |
209 | static unsigned long eat_addr(const char **argp, const char *what, |
1c1a9fa1 |
210 | const char *endchars, int *endchar_r) { |
211 | char whatbuf[100]; |
212 | unsigned long rv; |
213 | int i; |
214 | |
1c1a9fa1 |
215 | for (rv=0, i=0; |
216 | i<4; |
217 | i++) { |
218 | rv <<= 8; |
219 | sprintf(whatbuf,"%s byte #%d",what,i); |
220 | rv |= eat_number(argp,whatbuf, 0,255, i<3 ? "." : endchars, endchar_r); |
221 | } |
222 | |
1c1a9fa1 |
223 | return rv; |
224 | } |
225 | |
226 | static void eat_prefixmask(const char **argp, const char *what, |
1c1a9fa1 |
227 | const char *endchars, int *endchar_r, |
228 | unsigned long *prefix_r, unsigned long *mask_r, int *len_r) { |
229 | /* mask_r and len_r may be 0 */ |
230 | char whatbuf[100]; |
231 | int len; |
232 | unsigned long prefix, mask; |
233 | |
1e963473 |
234 | prefix= eat_addr(argp,what, "/",0); |
1c1a9fa1 |
235 | sprintf(whatbuf,"%s length",what); |
236 | len= eat_number(argp,whatbuf, 0,32, endchars,endchar_r); |
237 | |
238 | mask= (~0UL << (32-len)); |
1e963473 |
239 | if (prefix & ~mask) badusage("%s prefix %08lx not fully contained in mask %08lx\n", |
240 | what,prefix,mask); |
1c1a9fa1 |
241 | *prefix_r= prefix; |
242 | if (mask_r) *mask_r= mask; |
243 | if (len_r) *len_r= len; |
244 | } |
1e963473 |
245 | |
246 | static int addrnet_isin(unsigned long prefix, unsigned long mask, |
247 | unsigned long mprefix, unsigned long mmask) { |
248 | return !(~mask & mmask) && (prefix & mmask) == mprefix; |
249 | } |
1c1a9fa1 |
250 | |
1c1a9fa1 |
251 | |
1e963473 |
252 | static void permit(unsigned long pprefix, unsigned long pmask) { |
253 | int i, any; |
1c1a9fa1 |
254 | |
1e963473 |
255 | assert(!(pprefix & ~pmask)); |
1c1a9fa1 |
256 | |
1e963473 |
257 | if (!proto) fputs("permits",stdout); |
258 | if (addrnet_isin(localaddr,~0UL, pprefix,pmask)) { |
259 | if (!proto) fputs(" local-addr",stdout); |
260 | any= localallow= 1; |
261 | } |
262 | if (addrnet_isin(peeraddr,~0UL, pprefix,pmask)) { |
263 | if (!proto) fputs(" peer-addr",stdout); |
264 | any= peerallow= 1; |
265 | } |
266 | for (i=0; i<nexroutes; i++) { |
267 | if (addrnet_isin(exroutes[i].prefix,exroutes[i].mask, pprefix,pmask)) { |
268 | if (!proto) printf(" route#%d",i); |
269 | any= exroutes[i].allow= 1; |
270 | } |
271 | } |
272 | if (!proto) { |
273 | if (!any) fputs(" nothing!",stderr); |
274 | putchar('\n'); |
275 | } |
276 | } |
1c1a9fa1 |
277 | |
1e963473 |
278 | static void pconfig(const char *configstr, int truncated); |
279 | |
280 | static void pfile(const char *filename) { |
281 | FILE *file; |
282 | char buf[PATH_MAX]; |
283 | int l, truncated, c; |
284 | struct pplace npp, *cpp; |
285 | |
286 | for (cpp=cpplace; cpp; cpp=cpp->parent) { |
287 | if (!strcmp(cpp->filename,filename)) |
288 | badusage("recursive configuration file `%s'",filename); |
289 | } |
290 | |
291 | file= fopen(filename,"r"); |
292 | if (!file) |
293 | badusage("cannot open configuration file `%s': %s", filename, strerror(errno)); |
294 | |
295 | if (!proto) printf("config file `%s':\n",filename); |
296 | |
297 | npp.parent= cpplace; |
298 | npp.filename= filename; |
299 | npp.lineno= 0; |
300 | cpplace= &npp; |
301 | |
302 | while (fgets(buf, sizeof(buf), file)) { |
303 | npp.lineno++; |
304 | l= strlen(buf); |
305 | if (!l) continue; |
306 | |
307 | truncated= (buf[l-1] != '\n'); |
308 | while (l>0 && isspace((unsigned char) buf[l-1])) l--; |
309 | if (!l) continue; |
310 | buf[l]= 0; |
311 | |
312 | if (truncated) { |
313 | while ((c= getc(file)) != EOF && c != '\n'); |
314 | if (c == EOF) break; |
315 | } |
316 | |
317 | pconfig(buf,truncated); |
318 | } |
319 | if (ferror(file)) |
320 | badusage("failed while reading configuration file: %s", strerror(errno)); |
321 | |
322 | cpplace= npp.parent; |
323 | } |
324 | |
325 | static void pconfig(const char *configstr, int truncated) { |
326 | unsigned long fgid, tgid, pprefix, pmask; |
327 | int plen; |
328 | char ptxt[ATXTLEN]; |
329 | const char *gidlist; |
330 | |
331 | switch (configstr[0]) { |
332 | case '*': |
333 | if (strcmp(configstr,"*")) badusage("`*' directive must be only thing on line"); |
334 | permit(0UL,0UL); |
335 | return; |
336 | |
337 | case '#': |
338 | return; |
339 | |
340 | case '/': case '.': |
341 | if (truncated) badusage("filename too long (`%.100s...')",configstr); |
342 | pfile(configstr); |
343 | return; |
344 | |
345 | default: |
346 | if (!isdigit((unsigned char)configstr[0])) |
347 | badusage("unknown configuration directive"); |
348 | |
349 | fgid= eat_number(&configstr,"gid", 0,gidmaxval, ",",0); |
350 | eat_prefixmask(&configstr,"permitted-prefix", ",",0, &pprefix,&pmask,&plen); |
351 | if (!configstr && truncated) badusage("gid,prefix/len,... spec too long"); |
352 | |
353 | if (!proto) printf(" %5lu,%s/%d: ", fgid, ip2txt(pprefix,ptxt), plen); |
354 | |
355 | gidlist= getenv("USERV_GID"); |
356 | if (!gidlist) fatal("USERV_GID not set"); |
1c1a9fa1 |
357 | for (;;) { |
1e963473 |
358 | if (!gidlist) { |
359 | if (!proto) printf("no matching gid\n"); |
360 | return; |
1c1a9fa1 |
361 | } |
1e963473 |
362 | tgid= eat_number(&gidlist,"userv-gid", 0,gidmaxval, " ",0); |
363 | if (tgid == fgid) break; |
1c1a9fa1 |
364 | } |
1e963473 |
365 | permit(pprefix,pmask); |
366 | return; |
1c1a9fa1 |
367 | } |
1e963473 |
368 | } |
369 | |
370 | static void checkallow(int allow, const char *what, |
371 | const char *prefixtxt, const char *masktxt) { |
372 | if (allow) return; |
373 | fprintf(stderr,"userv-ipif service: access denied for %s, %s/%s\n", |
374 | what, prefixtxt, masktxt); |
375 | allallow= 0; |
376 | } |
377 | |
378 | static void parseargs(int argc, const char *const *argv) { |
379 | unsigned long routeaddr, routemask; |
380 | const char *carg; |
381 | const char *const *cprotop; |
382 | int i; |
383 | char erwhatbuf[100], erwhatbuf2[100]; |
384 | |
385 | if (argc < NARGS+1) { badusage("too few arguments"); } |
386 | if (argc > NARGS+1) { badusage("too many arguments"); } |
387 | |
388 | configstr= *++argv; |
1c1a9fa1 |
389 | |
390 | carg= *++argv; |
1e963473 |
391 | if (strcmp(carg,"--")) badusage("separator argument `--' not found, got `%s'",carg); |
1c1a9fa1 |
392 | |
1e963473 |
393 | carg= *++argv; |
394 | localaddr= eat_addr(&carg,"local-addr", ",",0); |
395 | peeraddr= eat_addr(&carg,"peer-addr", ",",0); |
1c1a9fa1 |
396 | mtu= eat_number(&carg,"mtu", 576,65536, ",",0); |
1e963473 |
397 | localallow= peerallow= 0; |
1c1a9fa1 |
398 | |
399 | if (!strcmp(carg,"debug")) { |
400 | proto= 0; |
401 | } else { |
402 | for (cprotop= protos_ok; |
403 | (proto= *cprotop) && strcmp(proto,carg); |
404 | cprotop++); |
405 | if (!proto) fatal("invalid protocol"); |
406 | } |
407 | |
408 | addrnet_mustdiffer("local-addr",localaddr,~0UL, "peer-addr",peeraddr,~0UL); |
409 | |
410 | carg= *++argv; |
411 | for (nexroutes=0; |
1e963473 |
412 | carg; |
413 | nexroutes++) { |
414 | if (nexroutes == MAXEXROUTES) |
415 | fatal("too many extra routes (only %d allowed)",MAXEXROUTES); |
416 | sprintf(erwhatbuf,"route#%d",nexroutes); |
1c1a9fa1 |
417 | |
1e963473 |
418 | eat_prefixmask(&carg,erwhatbuf, ",",0, &routeaddr,&routemask,0); |
419 | if (routemask == ~0UL) { |
420 | addrnet_mustdiffer(erwhatbuf,routeaddr,routemask, "local-addr",localaddr,~0UL); |
421 | addrnet_mustdiffer(erwhatbuf,routeaddr,routemask, "peer-addr",peeraddr,~0UL); |
422 | } |
1c1a9fa1 |
423 | for (i=0; i<nexroutes; i++) { |
1e963473 |
424 | sprintf(erwhatbuf2,"route#%d",i); |
1c1a9fa1 |
425 | addrnet_mustdiffer(erwhatbuf,routeaddr,routemask, |
426 | erwhatbuf2,exroutes[i].prefix,exroutes[i].mask); |
427 | } |
428 | exroutes[nexroutes].prefix= routeaddr; |
429 | exroutes[nexroutes].mask= routemask; |
1e963473 |
430 | exroutes[nexroutes].allow= 0; |
1c1a9fa1 |
431 | ip2txt(routeaddr,exroutes[nexroutes].prefixtxt); |
432 | ip2txt(routemask,exroutes[nexroutes].masktxt); |
433 | } |
434 | ip2txt(localaddr,localtxt); |
435 | ip2txt(peeraddr,peertxt); |
1e963473 |
436 | } |
437 | |
438 | static void checkpermit(void) { |
439 | int i; |
440 | char erwhatbuf[100]; |
1c1a9fa1 |
441 | |
1e963473 |
442 | allallow= 1; |
443 | checkallow(localallow,"local-addr", localtxt,"32"); |
444 | checkallow(peerallow,"peer-addr", peertxt,"32"); |
445 | for (i=0; i<nexroutes; i++) { |
446 | sprintf(erwhatbuf, "route#%d", i); |
447 | checkallow(exroutes[i].allow, erwhatbuf, exroutes[i].prefixtxt, exroutes[i].masktxt); |
448 | } |
449 | if (!allallow) fatal("access denied"); |
450 | } |
451 | |
452 | static void dumpdebug(void) __attribute__((noreturn)); |
453 | static void dumpdebug(void) { |
454 | int i; |
455 | char erwhatbuf[100]; |
456 | |
457 | printf("protocol: debug\n" |
458 | "local: %08lx == %s\n" |
459 | "peer: %08lx == %s\n" |
460 | "mtu: %ld\n" |
461 | "routes: %d\n", |
462 | localaddr, localtxt, |
463 | peeraddr, peertxt, |
464 | mtu, |
465 | nexroutes); |
466 | for (i=0; i<nexroutes; i++) { |
467 | sprintf(erwhatbuf, "route#%d:", i); |
468 | printf("%-9s %08lx/%08lx == %s/%s\n", |
469 | erwhatbuf, |
470 | exroutes[i].prefix, exroutes[i].mask, |
471 | exroutes[i].prefixtxt, exroutes[i].masktxt); |
1c1a9fa1 |
472 | } |
1e963473 |
473 | if (ferror(stdout) || fclose(stdout)) sysfatal("flush stdout"); |
474 | exit(0); |
475 | } |
476 | |
02b2392d |
477 | static void setsignals(void (*handler)(int), struct sigaction *sa, int chldflags) { |
478 | const int *signalp; |
479 | int r, sig; |
480 | |
481 | sa->sa_handler= handler; |
482 | sa->sa_flags= 0; |
483 | for (signalp=signals; (sig=*signalp); signalp++) { |
484 | r= sigaction(sig, sa, 0); if (r) sysfatal("uncatch signal"); |
485 | } |
486 | sa->sa_flags= chldflags; |
487 | r= sigaction(SIGCHLD, sa, 0); if (r) sysfatal("uncatch children"); |
488 | } |
489 | |
490 | static void setsigmask(const sigset_t *ss) { |
491 | int r; |
492 | |
493 | r= sigprocmask(SIG_SETMASK, ss, 0); |
494 | if (r) sysfatal("[un]block signals"); |
495 | } |
496 | |
497 | static void infork(void) { |
498 | struct sigaction sa; |
499 | |
500 | memset(&pids,0,sizeof(pids)); |
501 | sigemptyset(&sa.sa_mask); |
502 | setsignals(SIG_DFL,&sa,0); |
503 | setsigmask(&emptyset); |
504 | } |
505 | |
506 | static pid_t makesubproc(void (*entry)(void)) { |
507 | pid_t pid; |
508 | |
509 | pid= fork(); if (pid == (pid_t)-1) sysfatal("fork for subprocess"); |
510 | if (pid) return pid; |
511 | |
512 | infork(); |
513 | entry(); |
514 | abort(); |
515 | } |
516 | |
517 | static int task(void) { |
518 | pid_t pid; |
519 | |
520 | pid= fork(); |
521 | if (pids.byname.task == (pid_t)-1) sysfatal("fork for task"); |
522 | if (!pids.byname.task) { infork(); return 1; } |
523 | |
524 | pids.byname.task= pid; |
525 | while (pids.byname.task) sigsuspend(&emptyset); |
526 | return 0; |
527 | } |
528 | |
529 | static void sl_entry(void) { |
530 | if (dup2(slpipe[1],1) != 1) sysfatal("dup2 stdout in slattach child"); |
531 | execlp("slattach", "slattach", "-v", "-L", "-p",proto, ptyname, (char*)0); |
532 | sysfatal("cannot exec slattach"); |
533 | } |
534 | |
535 | static void cin_entry(void) { |
536 | if (dup2(ptmaster,1) != 1) sysfatal("dup2 stdout in cat input child"); |
537 | execlp("cat", "cat", (char*)0); |
538 | sysfatal("cannot exec cat input"); |
539 | } |
540 | |
541 | static void cout_entry(void) { |
542 | if (dup2(ptmaster,0) != 1) sysfatal("dup2 stdin in cat output child"); |
543 | execlp("cat", "cat", (char*)0); |
544 | sysfatal("cannot exec cat output"); |
545 | } |
546 | |
547 | static void sighandler(int signum) { |
548 | pid_t pid; |
549 | int estatus, status; |
550 | const char *taskfail; |
551 | |
552 | estatus= 4; |
553 | |
554 | if (signum == SIGCHLD) { |
555 | for (;;) { |
556 | pid= waitpid(-1,&status,WNOHANG); |
557 | if (!pid || pid == (pid_t)-1) return; |
558 | |
559 | if (pid == pids.byname.task) { |
560 | pids.byname.task= 0; |
561 | if (!status) return; |
562 | taskfail= "task"; |
563 | } else if (pid == pids.byname.cin) { |
564 | pids.byname.cin= 0; |
565 | if (status) { |
566 | taskfail= "input cat"; |
567 | } else { |
568 | taskfail= 0; |
569 | estatus= 0; |
570 | } |
571 | } else if (pid == pids.byname.cout) { |
572 | pids.byname.cout= 0; |
573 | taskfail= "output cat"; |
574 | } else if (pid == pids.byname.sl) { |
575 | pids.byname.sl= 0; |
576 | taskfail= "slattach"; |
577 | } else { |
578 | continue; |
579 | } |
580 | } |
581 | if (taskfail) { |
582 | fprintf(stderr, |
583 | "userv-ipif service: %s unexpected terminated with status code %d\n", |
584 | taskfail, status); |
585 | } |
586 | } else { |
587 | fprintf(stderr, |
588 | "userv-ipif service: received signal %d, terminating\n", |
589 | signum); |
590 | } |
591 | |
592 | terminate(estatus); |
593 | } |
594 | |
595 | static void startup(void) { |
596 | int r; |
597 | struct sigaction sa; |
598 | |
599 | sigfillset(&fullset); |
600 | sigemptyset(&emptyset); |
601 | |
602 | ptmaster= getpt(); if (ptmaster==-1) sysfatal("allocate pty master"); |
603 | r= grantpt(ptmaster); if (r) sysfatal("grab/grant pty slave"); |
604 | ptyname= ptsname(ptmaster); if (!ptyname) sysfatal("get pty slave name"); |
605 | r= chmod(ptyname,0600); if (r) sysfatal("chmod pty slave"); |
606 | |
607 | sigfillset(&sa.sa_mask); |
608 | setsignals(sighandler,&sa,SA_NOCLDSTOP); |
609 | setsigmask(&fullset); |
610 | } |
611 | |
612 | static void startslattach(void) { |
613 | FILE *piper; |
614 | char ifnbuf[200]; |
615 | int r, l, k; |
616 | |
617 | r= pipe(slpipe); if (r) sysfatal("create pipe"); |
618 | piper= fdopen(slpipe[0],"r"); if (!piper) sysfatal("fdopen pipe"); |
619 | |
620 | pids.byname.sl= makesubproc(sl_entry); |
621 | |
622 | close(slpipe[1]); |
623 | setsigmask(&emptyset); |
624 | if (!fgets(ifnbuf,sizeof(ifnbuf),piper)) { |
625 | if (ferror(piper)) sysfatal("cannot read ifname from slattach"); |
626 | else fatal("cannot read ifname from slattach"); |
627 | } |
628 | setsigmask(&fullset); |
629 | l= strlen(ifnbuf); |
630 | if (l<0 || ifnbuf[l-1] != '\n') fatal("slattach gave strange output `%s'",ifnbuf); |
631 | ifnbuf[l-1]= 0; |
632 | for (k=l; k>0 && ifnbuf[k-1]!=' '; k--); |
633 | ifname= ifnbuf+k; |
634 | } |
635 | |
636 | static void netconfigure(void) { |
637 | char mtutxt[100]; |
638 | int i; |
639 | |
640 | if (task()) { |
641 | sprintf(mtutxt,"%lu",mtu); |
642 | |
643 | execlp("ifconfig", "ifconfig", ifname, localtxt, |
644 | "netmask","255.255.255.255", "-broadcast", "pointopoint",peertxt, |
645 | "mtu",mtutxt, "up", (char*)0); |
646 | sysfatal("cannot exec ifconfig"); |
647 | } |
648 | |
649 | if (task()) { |
650 | execlp("route","route", "-host",localtxt, "netmask","255.255.255.255", |
651 | "dev",ifname, (char*)0); |
652 | sysfatal("cannot exec route (for local)"); |
653 | } |
654 | |
655 | if (task()) { |
656 | execlp("route","route", "-host",peertxt, "netmask","255.255.255.255", |
657 | "dev",ifname, (char*)0); |
658 | sysfatal("cannot exec route (for peer)"); |
659 | } |
660 | |
661 | for (i=0; i<nexroutes; i++) { |
662 | if (task()) { |
663 | execlp("route","route", "-net",exroutes[i].prefixtxt, |
664 | "netmask",exroutes[i].masktxt, |
665 | "gw",peertxt, "dev",ifname, (char*)0); |
666 | sysfatal("cannot exec route (for route)"); |
667 | } |
668 | } |
669 | } |
670 | |
671 | static void copydata(void) __attribute__((noreturn)); |
672 | static void copydata(void) { |
673 | pids.byname.cin= makesubproc(cin_entry); |
674 | pids.byname.cout= makesubproc(cout_entry); |
675 | |
676 | for (;;) sigsuspend(&emptyset); |
677 | } |
678 | |
1e963473 |
679 | int main(int argc, const char *const *argv) { |
680 | parseargs(argc,argv); |
681 | pconfig(configstr,0); |
682 | checkpermit(); |
683 | if (!proto) dumpdebug(); |
684 | |
02b2392d |
685 | startup(); |
686 | startslattach(); |
687 | netconfigure(); |
688 | copydata(); |
1c1a9fa1 |
689 | } |