#include #include #include int verbose; int trusted; void usage(void) { fprint(2, "usage: listen1 [-tv] address cmd args...\n"); exits("usage"); } void becomenone(void) { int fd; fd = open("#c/user", OWRITE); if(fd < 0 || write(fd, "none", strlen("none")) < 0) sysfatal("can't become none: %r"); close(fd); if(newns("none", nil) < 0) sysfatal("can't build namespace: %r"); } char* remoteaddr(char *dir) { static char buf[128]; char *p; int n, fd; snprint(buf, sizeof buf, "%s/remote", dir); fd = open(buf, OREAD); if(fd < 0) return ""; n = read(fd, buf, sizeof(buf)); close(fd); if(n > 0){ buf[n] = 0; p = strchr(buf, '!'); if(p) *p = 0; return buf; } return ""; } void main(int argc, char **argv) { char data[60], dir[40], ndir[40]; int ctl, nctl, fd; ARGBEGIN{ default: usage(); case 't': trusted = 1; break; case 'v': verbose = 1; break; }ARGEND if(argc < 2) usage(); if(!verbose){ close(1); fd = open("/dev/null", OWRITE); if(fd != 1){ dup(fd, 1); close(fd); } } if(!trusted) becomenone(); print("listen started\n"); ctl = announce(argv[0], dir); if(ctl < 0) sysfatal("announce %s: %r", argv[0]); for(;;){ nctl = listen(dir, ndir); if(nctl < 0) sysfatal("listen %s: %r", argv[0]); switch(rfork(RFFDG|RFPROC|RFNOWAIT|RFENVG|RFNAMEG|RFNOTEG)){ case -1: reject(ctl, ndir, "host overloaded"); close(nctl); continue; case 0: fd = accept(ctl, ndir); if(fd < 0){ fprint(2, "accept %s: can't open %s/data: %r", argv[0], ndir); _exits(0); } print("incoming call for %s from %s in %s\n", argv[0], remoteaddr(ndir), ndir); fprint(nctl, "keepalive"); close(ctl); close(nctl); putenv("net", ndir); sprint(data, "%s/data", ndir); bind(data, "/dev/cons", MREPL); dup(fd, 0); dup(fd, 1); dup(fd, 2); close(fd); exec(argv[1], argv+1); fprint(2, "exec: %r"); exits(nil); default: close(nctl); break; } } exits(nil); }