/* * User Process PPP * * Written by Toshiharu OHNO (tony-o@iij.ad.jp) * * Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd. * * Redistribution and use in source and binary forms are permitted * provided that the above copyright notice and this paragraph are * duplicated in all such forms and that any documentation, * advertising materials, and other materials related to such * distribution and use acknowledge that the software was developed * by the Internet Initiative Japan, Inc. The name of the * IIJ may not be used to endorse or promote products derived * from this software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. * * $Id: main.c,v 1.121.2.51 1998/04/25 10:49:26 brian Exp $ * * TODO: */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "mbuf.h" #include "log.h" #include "defs.h" #include "id.h" #include "timer.h" #include "fsm.h" #include "lqr.h" #include "hdlc.h" #include "lcp.h" #include "ccp.h" #include "iplist.h" #include "throughput.h" #include "slcompress.h" #include "ipcp.h" #include "filter.h" #include "descriptor.h" #include "link.h" #include "mp.h" #include "bundle.h" #include "loadalias.h" #include "auth.h" #include "systems.h" #include "ip.h" #include "sig.h" #include "main.h" #include "pathnames.h" #include "tun.h" #include "server.h" #include "prompt.h" #include "chat.h" #include "chap.h" #include "datalink.h" #ifndef O_NONBLOCK #ifdef O_NDELAY #define O_NONBLOCK O_NDELAY #endif #endif static char pid_filename[MAXPATHLEN]; static void DoLoop(struct bundle *, struct prompt *); static void TerminalStop(int); static const char *ex_desc(int); static struct bundle *SignalBundle; static struct prompt *SignalPrompt; void Cleanup(int excode) { SignalBundle->CleaningUp = 1; if (bundle_Phase(SignalBundle) != PHASE_DEAD) bundle_Close(SignalBundle, NULL, 1); } void AbortProgram(int excode) { ServerClose(SignalBundle); ID0unlink(pid_filename); LogPrintf(LogPHASE, "PPP Terminated (%s).\n", ex_desc(excode)); bundle_Close(SignalBundle, NULL, 1); bundle_Destroy(SignalBundle); LogClose(); exit(excode); } static void CloseConnection(int signo) { /* NOTE, these are manual, we've done a setsid() */ struct datalink *dl; pending_signal(SIGINT, SIG_IGN); LogPrintf(LogPHASE, "Caught signal %d, abort connection(s)\n", signo); for (dl = SignalBundle->links; dl; dl = dl->next) datalink_Down(dl, 1); pending_signal(SIGINT, CloseConnection); } static void CloseSession(int signo) { LogPrintf(LogPHASE, "Signal %d, terminate.\n", signo); Cleanup(EX_TERM); } static pid_t BGPid = 0; static void KillChild(int signo) { LogPrintf(LogPHASE, "Parent: Signal %d\n", signo); kill(BGPid, SIGINT); } static void TerminalCont(int signo) { signal(SIGCONT, SIG_DFL); prompt_Continue(SignalPrompt); } static void TerminalStop(int signo) { prompt_Suspend(SignalPrompt); signal(SIGCONT, TerminalCont); raise(SIGSTOP); } #if 0 /* What's our passwd :-O */ static void SetUpServer(int signo) { int res; VarHaveLocalAuthKey = 0; LocalAuthInit(); if ((res = ServerTcpOpen(SERVER_PORT + SignalBundle->unit)) != 0) LogPrintf(LogERROR, "SIGUSR1: Failed %d to open port %d\n", res, SERVER_PORT + SignalBundle->unit); } #endif static void BringDownServer(int signo) { /* Drops all child prompts too ! */ ServerClose(SignalBundle); } static const char * ex_desc(int ex) { static char num[12]; static const char *desc[] = { "normal", "start", "sock", "modem", "dial", "dead", "done", "reboot", "errdead", "hangup", "term", "nodial", "nologin" }; if (ex >= 0 && ex < sizeof desc / sizeof *desc) return desc[ex]; snprintf(num, sizeof num, "%d", ex); return num; } static void Usage(void) { fprintf(stderr, "Usage: ppp [-auto | -background | -direct | -dedicated | -ddial ]" #ifndef NOALIAS " [ -alias ]" #endif " [system]\n"); exit(EX_START); } static char * ProcessArgs(int argc, char **argv, int *mode) { int optc, labelrequired; char *cp; optc = labelrequired = 0; *mode = PHYS_MANUAL; while (argc > 0 && **argv == '-') { cp = *argv + 1; if (strcmp(cp, "auto") == 0) { *mode = PHYS_DEMAND; labelrequired = 1; } else if (strcmp(cp, "background") == 0) { *mode = PHYS_1OFF; labelrequired = 1; } else if (strcmp(cp, "direct") == 0) *mode = PHYS_STDIN; else if (strcmp(cp, "dedicated") == 0) *mode = PHYS_DEDICATED; else if (strcmp(cp, "ddial") == 0) { *mode = PHYS_PERM; labelrequired = 1; } else if (strcmp(cp, "alias") == 0) { #ifndef NOALIAS if (loadAliasHandlers() != 0) #endif LogPrintf(LogWARN, "Cannot load alias library\n"); optc--; /* this option isn't exclusive */ } else Usage(); optc++; argv++; argc--; } if (argc > 1) { fprintf(stderr, "You may specify only one system label.\n"); exit(EX_START); } if (optc > 1) { fprintf(stderr, "You may specify only one mode.\n"); exit(EX_START); } if (labelrequired && argc != 1) { fprintf(stderr, "Destination system must be specified in" " auto, background or ddial mode.\n"); exit(EX_START); } return argc == 1 ? *argv : NULL; /* Don't SetLabel yet ! */ } int main(int argc, char **argv) { FILE *lockfile; char *name, *label; int nfds, mode; struct bundle *bundle; struct prompt *prompt; nfds = getdtablesize(); if (nfds >= FD_SETSIZE) /* * If we've got loads of file descriptors, make sure they're all * closed. If they aren't, we may end up with a seg fault when our * `fd_set's get too big when select()ing ! */ while (--nfds > 2) close(nfds); name = strrchr(argv[0], '/'); LogOpen(name ? name + 1 : argv[0]); argc--; argv++; label = ProcessArgs(argc, argv, &mode); #ifdef __FreeBSD__ /* * A FreeBSD hack to dodge a bug in the tty driver that drops output * occasionally.... I must find the real reason some time. To display * the dodgy behaviour, comment out this bit, make yourself a large * routing table and then run ppp in interactive mode. The `show route' * command will drop chunks of data !!! */ if (mode == PHYS_MANUAL) { close(STDIN_FILENO); if (open(_PATH_TTY, O_RDONLY) != STDIN_FILENO) { fprintf(stderr, "Cannot open %s for input !\n", _PATH_TTY); return 2; } } #endif /* Allow output for the moment (except in direct mode) */ if (mode == PHYS_STDIN) prompt = NULL; else { const char *m; SignalPrompt = prompt = prompt_Create(NULL, NULL, PROMPT_STD); if (mode == PHYS_PERM) m = "direct dial"; else if (mode & PHYS_1OFF) m = "background"; else if (mode & PHYS_DEMAND) m = "auto"; else if (mode & PHYS_DEDICATED) m = "dedicated"; else if (mode & PHYS_MANUAL) m = "interactive"; else m = NULL; if (m) prompt_Printf(prompt, "Working in %s mode\n", m); } ID0init(); if (ID0realuid() != 0) { char conf[200], *ptr; snprintf(conf, sizeof conf, "%s/%s", _PATH_PPP, CONFFILE); do { if (!access(conf, W_OK)) { LogPrintf(LogALERT, "ppp: Access violation: Please protect %s\n", conf); return -1; } ptr = conf + strlen(conf)-2; while (ptr > conf && *ptr != '/') *ptr-- = '\0'; } while (ptr >= conf); } if (!ValidSystem(label, prompt, mode)) { fprintf(stderr, "You may not use ppp in this mode with this label\n"); if (mode == PHYS_STDIN) { const char *l; l = label ? label : "default"; LogPrintf(LogWARN, "Label %s rejected -direct connection\n", l); } LogClose(); return 1; } if ((bundle = bundle_Create(TUN_PREFIX, prompt, mode)) == NULL) { LogPrintf(LogWARN, "bundle_Create: %s\n", strerror(errno)); return EX_START; } SignalBundle = bundle; if (SelectSystem(bundle, "default", CONFFILE, prompt) < 0) prompt_Printf(prompt, "Warning: No default entry found in config file.\n"); pending_signal(SIGHUP, CloseSession); pending_signal(SIGTERM, CloseSession); pending_signal(SIGINT, CloseConnection); pending_signal(SIGQUIT, CloseSession); pending_signal(SIGALRM, SIG_IGN); signal(SIGPIPE, SIG_IGN); if (mode == PHYS_MANUAL) pending_signal(SIGTSTP, TerminalStop); #if 0 /* What's our passwd :-O */ pending_signal(SIGUSR1, SetUpServer); #endif pending_signal(SIGUSR2, BringDownServer); if (label) { /* * Set label both before and after SelectSystem ! * This way, "set enddisc label" works during SelectSystem, and we * also end up with the correct label if we have embedded load * commands. */ bundle_SetLabel(bundle, label); if (SelectSystem(bundle, label, CONFFILE, prompt) < 0) { prompt_Printf(prompt, "Destination system (%s) not found.\n", label); AbortProgram(EX_START); } bundle_SetLabel(bundle, label); if (mode == PHYS_DEMAND && bundle->ncp.ipcp.cfg.peer_range.ipaddr.s_addr == INADDR_ANY) { prompt_Printf(prompt, "You must \"set ifaddr\" with a peer address " "in label %s for auto mode.\n", label); AbortProgram(EX_START); } } if (mode != PHYS_MANUAL) { if (mode != PHYS_STDIN) { int bgpipe[2]; pid_t bgpid; if (mode == PHYS_1OFF && pipe(bgpipe)) { LogPrintf(LogERROR, "pipe: %s\n", strerror(errno)); AbortProgram(EX_SOCK); } bgpid = fork(); if (bgpid == -1) { LogPrintf(LogERROR, "fork: %s\n", strerror(errno)); AbortProgram(EX_SOCK); } if (bgpid) { char c = EX_NORMAL; if (mode == PHYS_1OFF) { close(bgpipe[1]); BGPid = bgpid; /* If we get a signal, kill the child */ signal(SIGHUP, KillChild); signal(SIGTERM, KillChild); signal(SIGINT, KillChild); signal(SIGQUIT, KillChild); /* Wait for our child to close its pipe before we exit */ if (read(bgpipe[0], &c, 1) != 1) { prompt_Printf(prompt, "Child exit, no status.\n"); LogPrintf(LogPHASE, "Parent: Child exit, no status.\n"); } else if (c == EX_NORMAL) { prompt_Printf(prompt, "PPP enabled.\n"); LogPrintf(LogPHASE, "Parent: PPP enabled.\n"); } else { prompt_Printf(prompt, "Child failed (%s).\n", ex_desc((int) c)); LogPrintf(LogPHASE, "Parent: Child failed (%s).\n", ex_desc((int) c)); } close(bgpipe[0]); } return c; } else if (mode == PHYS_1OFF) { close(bgpipe[0]); bundle->notify.fd = bgpipe[1]; } /* -auto, -dedicated, -ddial & -background */ prompt_Destroy(prompt, 0); close(STDOUT_FILENO); close(STDERR_FILENO); close(STDIN_FILENO); setsid(); } else { /* -direct: STDIN_FILENO gets used by modem_Open */ prompt_TtyInit(NULL); close(STDOUT_FILENO); close(STDERR_FILENO); } } else { /* Interactive mode */ close(STDERR_FILENO); prompt_TtyInit(prompt); prompt_TtyCommandMode(prompt); prompt_Required(prompt); } snprintf(pid_filename, sizeof pid_filename, "%stun%d.pid", _PATH_VARRUN, bundle->unit); lockfile = ID0fopen(pid_filename, "w"); if (lockfile != NULL) { fprintf(lockfile, "%d\n", (int) getpid()); fclose(lockfile); } #ifndef RELEASE_CRUNCH else LogPrintf(LogALERT, "Warning: Can't create %s: %s\n", pid_filename, strerror(errno)); #endif LogPrintf(LogPHASE, "PPP Started (%s mode).\n", mode2Nam(mode)); DoLoop(bundle, prompt); AbortProgram(EX_NORMAL); return EX_NORMAL; } static void DoLoop(struct bundle *bundle, struct prompt *prompt) { fd_set rfds, wfds, efds; int pri, i, n, nfds; int qlen; struct tun_data tun; do { nfds = 0; FD_ZERO(&rfds); FD_ZERO(&wfds); FD_ZERO(&efds); qlen = bundle_FillQueues(bundle); handle_signals(); descriptor_UpdateSet(&bundle->desc, &rfds, &wfds, &efds, &nfds); descriptor_UpdateSet(&server.desc, &rfds, &wfds, &efds, &nfds); descriptor_UpdateSet(&bundle->ncp.mp.server.desc, &rfds, &wfds, &efds, &nfds); /* If there are aren't many packets queued, look for some more. */ if (qlen < 20 && bundle->tun_fd >= 0) { if (bundle->tun_fd + 1 > nfds) nfds = bundle->tun_fd + 1; FD_SET(bundle->tun_fd, &rfds); } if (bundle_IsDead(bundle)) /* Don't select - we'll be here forever */ break; i = select(nfds, &rfds, &wfds, &efds, NULL); if (i == 0) continue; if (i < 0) { if (errno == EINTR) { handle_signals(); continue; } LogPrintf(LogERROR, "DoLoop: select(): %s\n", strerror(errno)); break; } for (i = 0; i <= nfds; i++) if (FD_ISSET(i, &efds)) { LogPrintf(LogALERT, "Exception detected on descriptor %d\n", i); break; } if (descriptor_IsSet(&bundle->ncp.mp.server.desc, &rfds)) descriptor_Read(&bundle->ncp.mp.server.desc, bundle, &rfds); if (descriptor_IsSet(&server.desc, &rfds)) descriptor_Read(&server.desc, bundle, &rfds); if (descriptor_IsSet(&bundle->desc, &wfds)) descriptor_Write(&bundle->desc, bundle, &wfds); if (descriptor_IsSet(&bundle->desc, &rfds)) descriptor_Read(&bundle->desc, bundle, &rfds); if (bundle->tun_fd >= 0 && FD_ISSET(bundle->tun_fd, &rfds)) { /* something to read from tun */ n = read(bundle->tun_fd, &tun, sizeof tun); if (n < 0) { LogPrintf(LogERROR, "read from tun: %s\n", strerror(errno)); continue; } n -= sizeof tun - sizeof tun.data; if (n <= 0) { LogPrintf(LogERROR, "read from tun: Only %d bytes read\n", n); continue; } if (!tun_check_header(tun, AF_INET)) continue; if (((struct ip *)tun.data)->ip_dst.s_addr == bundle->ncp.ipcp.my_ip.s_addr) { /* we've been asked to send something addressed *to* us :( */ if (Enabled(bundle, OPT_LOOPBACK)) { pri = PacketCheck(bundle, tun.data, n, &bundle->filter.in); if (pri >= 0) { struct mbuf *bp; #ifndef NOALIAS if (AliasEnabled()) { (*PacketAlias.In)(tun.data, sizeof tun.data); n = ntohs(((struct ip *)tun.data)->ip_len); } #endif bp = mballoc(n, MB_IPIN); memcpy(MBUF_CTOP(bp), tun.data, n); IpInput(bundle, bp); LogPrintf(LogDEBUG, "Looped back packet addressed to myself\n"); } continue; } else LogPrintf(LogDEBUG, "Oops - forwarding packet addressed to myself\n"); } /* * Process on-demand dialup. Output packets are queued within tunnel * device until IPCP is opened. */ if (bundle_Phase(bundle) == PHASE_DEAD) { /* * Note, we must be in AUTO mode :-/ otherwise our interface should * *not* be UP and we can't receive data */ if ((pri = PacketCheck(bundle, tun.data, n, &bundle->filter.dial)) >= 0) bundle_Open(bundle, NULL, PHYS_DEMAND); else /* * Drop the packet. If we were to queue it, we'd just end up with * a pile of timed-out data in our output queue by the time we get * around to actually dialing. We'd also prematurely reach the * threshold at which we stop select()ing to read() the tun * device - breaking auto-dial. */ continue; } pri = PacketCheck(bundle, tun.data, n, &bundle->filter.out); if (pri >= 0) { #ifndef NOALIAS if (AliasEnabled()) { (*PacketAlias.Out)(tun.data, sizeof tun.data); n = ntohs(((struct ip *)tun.data)->ip_len); } #endif IpEnqueue(pri, tun.data, n); } } } while (bundle_CleanDatalinks(bundle), !bundle_IsDead(bundle)); LogPrintf(LogDEBUG, "DoLoop done.\n"); }