/* * 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 1.23 1996/12/03 21:38:48 nate Exp $ * * TODO: * o Add commands for traffic summary, version display, etc. * o Add signal handler for misc controls. */ #include "fsm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include "modem.h" #include "os.h" #include "hdlc.h" #include "ccp.h" #include "lcp.h" #include "ipcp.h" #include "vars.h" #include "auth.h" #include "filter.h" #include "systems.h" #include "ip.h" #include "alias.h" #define LAUTH_M1 "Warning: No password entry for this host in ppp.secret\n" #define LAUTH_M2 "Warning: All manipulation is allowed by anyone in the world\n" #ifndef O_NONBLOCK #ifdef O_NDELAY #define O_NONBLOCK O_NDELAY #endif #endif extern void VjInit(), AsyncInit(); extern void AsyncInput(), IpOutput(); extern int SelectSystem(); extern void DecodeCommand(), Prompt(); extern int aft_cmd; extern int IsInteractive(); extern struct in_addr ifnetmask; static void DoLoop(void); static void TerminalStop(); static struct termios oldtio; /* Original tty mode */ static struct termios comtio; /* Command level tty mode */ int TermMode; static int server; struct sockaddr_in ifsin; char pid_filename[128]; static void TtyInit() { struct termios newtio; int stat; stat = fcntl(0, F_GETFL, 0); stat |= O_NONBLOCK; fcntl(0, F_SETFL, stat); newtio = oldtio; newtio.c_lflag &= ~(ECHO|ISIG|ICANON); newtio.c_iflag = 0; newtio.c_oflag &= ~OPOST; newtio.c_cc[VEOF] = _POSIX_VDISABLE; newtio.c_cc[VINTR] = _POSIX_VDISABLE; newtio.c_cc[VMIN] = 1; newtio.c_cc[VTIME] = 0; newtio.c_cflag |= CS8; tcsetattr(0, TCSADRAIN, &newtio); comtio = newtio; } /* * Set tty into command mode. We allow canonical input and echo processing. */ void TtyCommandMode(prompt) int prompt; { struct termios newtio; int stat; if (!(mode & MODE_INTER)) return; tcgetattr(0, &newtio); newtio.c_lflag |= (ECHO|ISIG|ICANON); newtio.c_iflag = oldtio.c_iflag; newtio.c_oflag |= OPOST; tcsetattr(0, TCSADRAIN, &newtio); stat = fcntl(0, F_GETFL, 0); stat |= O_NONBLOCK; fcntl(0, F_SETFL, stat); TermMode = 0; if(prompt) Prompt(0); } /* * Set tty into terminal mode which is used while we invoke term command. */ void TtyTermMode() { int stat; tcsetattr(0, TCSADRAIN, &comtio); stat = fcntl(0, F_GETFL, 0); stat &= ~O_NONBLOCK; fcntl(0, F_SETFL, stat); TermMode = 1; } void TtyOldMode() { int stat; stat = fcntl(0, F_GETFL, 0); stat &= ~O_NONBLOCK; fcntl(0, F_SETFL, stat); tcsetattr(0, TCSANOW, &oldtio); } void Cleanup(excode) int excode; { OsLinkdown(); OsCloseLink(1); sleep(1); if (mode & MODE_AUTO) { DeleteIfRoutes(1); unlink(pid_filename); } OsInterfaceDown(1); LogPrintf(LOG_PHASE_BIT, "PPP Terminated.\n"); LogClose(); if (server > 0) close(server); TtyOldMode(); exit(excode); } static void Hangup(signo) int signo; { if (signo == SIGSEGV) { LogPrintf(LOG_PHASE_BIT, "Signal %d, core dump.\n", signo); LogClose(); abort(); } LogPrintf(LOG_PHASE_BIT, "Signal %d, hangup.\n", signo); Cleanup(EX_HANGUP); } static void CloseSession(signo) int signo; { LogPrintf(LOG_PHASE_BIT, "Signal %d, terminate.\n", signo); LcpClose(); Cleanup(EX_TERM); } static void TerminalCont() { (void)signal(SIGCONT, SIG_DFL); (void)signal(SIGTSTP, TerminalStop); TtyCommandMode(getpgrp() == tcgetpgrp(0)); } static void TerminalStop(signo) int signo; { (void)signal(SIGCONT, TerminalCont); TtyOldMode(); signal(SIGTSTP, SIG_DFL); kill(getpid(), signo); } void Usage() { fprintf(stderr, "Usage: ppp [-auto | -direct | -dedicated | -ddial ] [ -alias ] [system]\n"); exit(EX_START); } void ProcessArgs(int argc, char **argv) { int optc; char *cp; optc = 0; while (argc > 0 && **argv == '-') { cp = *argv + 1; if (strcmp(cp, "auto") == 0) mode |= MODE_AUTO; else if (strcmp(cp, "direct") == 0) mode |= MODE_DIRECT; else if (strcmp(cp, "dedicated") == 0) mode |= MODE_DEDICATED; else if (strcmp(cp, "ddial") == 0) mode |= MODE_DDIAL|MODE_AUTO; else if (strcmp(cp, "alias") == 0) { mode |= MODE_ALIAS; optc--; /* this option isn't exclusive */ } else Usage(); optc++; argv++; argc--; } if (argc > 1) { fprintf(stderr, "specify only one system label.\n"); exit(EX_START); } if (argc == 1) dstsystem = *argv; if (optc > 1) { fprintf(stderr, "specify only one mode.\n"); exit(EX_START); } } static void Greetings() { printf("User Process PPP. Written by Toshiharu OHNO.\r\n"); fflush(stdout); } void main(argc, argv) int argc; char **argv; { int tunno; argc--; argv++; mode = MODE_INTER; /* default operation is interactive mode */ netfd = -1; ProcessArgs(argc, argv); Greetings(); GetUid(); IpcpDefAddress(); InitAlias(); if (SelectSystem("default", CONFFILE) < 0) { fprintf(stderr, "Warning: No default entry is given in config file.\n"); } if (LogOpen()) exit(EX_START); switch ( LocalAuthInit() ) { case NOT_FOUND: fprintf(stderr,LAUTH_M1); fprintf(stderr,LAUTH_M2); fflush (stderr); /* Fall down */ case VALID: VarLocalAuth = LOCAL_AUTH; break; default: break; } if (OpenTunnel(&tunno) < 0) { perror("open_tun"); exit(EX_START); } if (mode & (MODE_AUTO|MODE_DIRECT|MODE_DEDICATED)) mode &= ~MODE_INTER; if (mode & MODE_INTER) { printf("Interactive mode\n"); netfd = 0; } else if (mode & MODE_AUTO) { printf("Automatic Dialer mode\n"); if (dstsystem == NULL) { fprintf(stderr, "Destination system must be specified in auto or ddial mode.\n"); exit(EX_START); } } tcgetattr(0, &oldtio); /* Save original tty mode */ signal(SIGHUP, Hangup); signal(SIGTERM, CloseSession); signal(SIGINT, CloseSession); signal(SIGQUIT, CloseSession); #ifdef SIGSEGV signal(SIGSEGV, Hangup); #endif #ifdef SIGPIPE signal(SIGPIPE, Hangup); #endif #ifdef SIGALRM signal(SIGALRM, SIG_IGN); #endif if(mode & MODE_INTER) { #ifdef SIGTSTP signal(SIGTSTP, TerminalStop); #endif #ifdef SIGTTIN signal(SIGTTIN, TerminalStop); #endif #ifdef SIGTTOU signal(SIGTTOU, SIG_IGN); #endif } if (dstsystem) { if (SelectSystem(dstsystem, CONFFILE) < 0) { fprintf(stderr, "Destination system not found in conf file.\n"); Cleanup(EX_START); } if ((mode & MODE_AUTO) && DefHisAddress.ipaddr.s_addr == INADDR_ANY) { fprintf(stderr, "Must specify dstaddr with auto or ddial mode.\n"); Cleanup(EX_START); } } if (mode & MODE_DIRECT) printf("Packet mode enabled.\n"); #ifdef notdef if (mode & MODE_AUTO) { OsSetIpaddress(IpcpInfo.want_ipaddr, IpcpInfo.his_ipaddr, ifnetmask); } #endif if (!(mode & MODE_INTER)) { int port = SERVER_PORT + tunno; /* * Create server socket and listen at there. */ server = socket(PF_INET, SOCK_STREAM, 0); if (server < 0) { perror("socket"); Cleanup(EX_SOCK); } ifsin.sin_family = AF_INET; ifsin.sin_addr.s_addr = INADDR_ANY; ifsin.sin_port = htons(port); if (bind(server, (struct sockaddr *) &ifsin, sizeof(ifsin)) < 0) { perror("bind"); if (errno == EADDRINUSE) fprintf(stderr, "Wait for a while, then try again.\n"); Cleanup(EX_SOCK); } listen(server, 5); DupLog(); if (!(mode & MODE_DIRECT)) { int fd; char pid[32]; if (fork()) exit(0); snprintf(pid_filename, sizeof (pid_filename), "%s/PPP.%s", _PATH_VARRUN, dstsystem); unlink(pid_filename); sprintf(pid, "%d\n", (int)getpid()); if ((fd = open(pid_filename, O_RDWR|O_CREAT, 0666)) != -1) { write(fd, pid, strlen(pid)); close(fd); } } LogPrintf(LOG_PHASE_BIT, "Listening at %d.\n", port); #ifdef DOTTYINIT if (mode & (MODE_DIRECT|MODE_DEDICATED)) { /* } */ #else if (mode & MODE_DIRECT) { #endif TtyInit(); } else { int fd; setsid(); /* detach control tty */ if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { (void)dup2(fd, STDIN_FILENO); (void)dup2(fd, STDOUT_FILENO); (void)dup2(fd, STDERR_FILENO); if (fd > 2) (void)close (fd); } } } else { server = -1; TtyInit(); TtyCommandMode(1); } LogPrintf(LOG_PHASE_BIT, "PPP Started.\n"); do DoLoop(); while (mode & MODE_DEDICATED); Cleanup(EX_DONE); } /* * Turn into packet mode, where we speek PPP. */ void PacketMode() { if (RawModem(modem) < 0) { fprintf(stderr, "Not connected.\r\n"); return; } AsyncInit(); VjInit(); LcpInit(); IpcpInit(); CcpInit(); LcpUp(); if (mode & (MODE_DIRECT|MODE_DEDICATED)) LcpOpen(OPEN_ACTIVE); else LcpOpen(VarOpenMode); if ((mode & (MODE_INTER|MODE_AUTO)) == MODE_INTER) { TtyCommandMode(1); fprintf(stderr, "Packet mode.\r\n"); aft_cmd = 1; } } static void ShowHelp() { fprintf(stderr, "The following commands are available:\r\n"); fprintf(stderr, " ~p\tEnter to Packet mode\r\n"); fprintf(stderr, " ~-\tDecrease log level\r\n"); fprintf(stderr, " ~+\tIncrease log level\r\n"); fprintf(stderr, " ~.\tTerminate program\r\n"); fprintf(stderr, " ~?\tThis help\r\n"); } static void ReadTty() { int n; char ch; static int ttystate; #define MAXLINESIZE 200 char linebuff[MAXLINESIZE]; #ifdef DEBUG logprintf("termode = %d, netfd = %d, mode = %d\n", TermMode, netfd, mode); #endif if (!TermMode) { n = read(netfd, linebuff, sizeof(linebuff)-1); aft_cmd = 1; if (n > 0) { DecodeCommand(linebuff, n, 1); } else { #ifdef DEBUG logprintf("connection closed.\n"); #endif close(netfd); netfd = -1; mode &= ~MODE_INTER; } return; } /* * We are in terminal mode, decode special sequences */ n = read(0, &ch, 1); #ifdef DEBUG logprintf("got %d bytes\n", n); #endif if (n > 0) { switch (ttystate) { case 0: if (ch == '~') ttystate++; else write(modem, &ch, n); break; case 1: switch (ch) { case '?': ShowHelp(); break; case '-': if (loglevel > 0) { loglevel--; fprintf(stderr, "New loglevel is %d\r\n", loglevel); } break; case '+': loglevel++; fprintf(stderr, "New loglevel is %d\r\n", loglevel); break; #ifdef DEBUG case 'm': ShowMemMap(); break; #endif case 'p': /* * XXX: Should check carrier. */ if (LcpFsm.state <= ST_CLOSED) { VarOpenMode = OPEN_ACTIVE; PacketMode(); } break; #ifdef DEBUG case 't': ShowTimers(); break; #endif case '.': TermMode = 1; TtyCommandMode(1); break; default: if (write(modem, &ch, n) < 0) fprintf(stderr, "err in write.\r\n"); break; } ttystate = 0; break; } } } /* * Here, we'll try to detect HDLC frame */ static char *FrameHeaders[] = { "\176\377\003\300\041", "\176\377\175\043\300\041", "\176\177\175\043\100\041", "\176\175\337\175\043\300\041", "\176\175\137\175\043\100\041", NULL, }; u_char * HdlcDetect(cp, n) u_char *cp; int n; { char *ptr, *fp, **hp; cp[n] = '\0'; /* be sure to null terminated */ ptr = NULL; for (hp = FrameHeaders; *hp; hp++) { fp = *hp; if (DEV_IS_SYNC) fp++; ptr = strstr((char *)cp, fp); if (ptr) break; } return((u_char *)ptr); } static struct pppTimer RedialTimer; static void RedialTimeout() { StopTimer(&RedialTimer); LogPrintf(LOG_PHASE_BIT, "Redialing timer expired.\n"); } static void StartRedialTimer() { StopTimer(&RedialTimer); if (VarRedialTimeout) { LogPrintf(LOG_PHASE_BIT, "Enter pause for redialing.\n"); RedialTimer.state = TIMER_STOPPED; if (VarRedialTimeout > 0) RedialTimer.load = VarRedialTimeout * SECTICKS; else RedialTimer.load = (random() % REDIAL_PERIOD) * SECTICKS; RedialTimer.func = RedialTimeout; StartTimer(&RedialTimer); } } static void DoLoop() { fd_set rfds, wfds, efds; int pri, i, n, wfd; struct sockaddr_in hisaddr; struct timeval timeout, *tp; int ssize = sizeof(hisaddr); u_char *cp; u_char rbuff[MAX_MRU]; int dial_up; int tries; int qlen; pid_t pgroup; pgroup = getpgrp(); if (mode & MODE_DIRECT) { modem = OpenModem(mode); LogPrintf(LOG_PHASE_BIT, "Packet mode enabled\n"); fflush(stderr); PacketMode(); } else if (mode & MODE_DEDICATED) { if (!modem) modem = OpenModem(mode); } fflush(stdout); timeout.tv_sec = 0; timeout.tv_usec = 0; dial_up = FALSE; /* XXXX */ tries = 0; for (;;) { FD_ZERO(&rfds); FD_ZERO(&wfds); FD_ZERO(&efds); /* * If the link is down and we're in DDIAL mode, bring it back * up. */ if (mode & MODE_DDIAL && LcpFsm.state <= ST_CLOSED) dial_up = TRUE; /* * If Ip packet for output is enqueued and require dial up, * Just do it! */ if ( dial_up && RedialTimer.state != TIMER_RUNNING ) { /* XXX */ #ifdef DEBUG logprintf("going to dial: modem = %d\n", modem); #endif modem = OpenModem(mode); if (modem < 0) { modem = 0; /* Set intial value for next OpenModem */ StartRedialTimer(); } else { tries++; LogPrintf(LOG_CHAT_BIT, "Dial attempt %u\n", tries); if (DialModem()) { sleep(1); /* little pause to allow peer starts */ ModemTimeout(); PacketMode(); dial_up = FALSE; tries = 0; } else { CloseModem(); /* Dial failed. Keep quite during redial wait period. */ StartRedialTimer(); if (VarDialTries && tries >= VarDialTries) { dial_up = FALSE; tries = 0; } } } } qlen = ModemQlen(); if (qlen == 0) { IpStartOutput(); qlen = ModemQlen(); } if (modem) { FD_SET(modem, &rfds); FD_SET(modem, &efds); if (qlen > 0) { FD_SET(modem, &wfds); } } if (server > 0) FD_SET(server, &rfds); /* *** IMPORTANT *** * * CPU is serviced every TICKUNIT micro seconds. * This value must be chosen with great care. If this values is * too big, it results loss of characters from modem and poor responce. * If this values is too small, ppp process eats many CPU time. */ #ifndef SIGALRM usleep(TICKUNIT); TimerService(); #endif /* If there are aren't many packets queued, look for some more. */ if (qlen < 20) FD_SET(tun_in, &rfds); if (netfd > -1) { FD_SET(netfd, &rfds); FD_SET(netfd, &efds); } #ifndef SIGALRM /* * Normally, select() will not block because modem is writable. * In AUTO mode, select will block until we find packet from tun */ tp = (RedialTimer.state == TIMER_RUNNING)? &timeout : NULL; i = select(tun_in+10, &rfds, &wfds, &efds, tp); #else /* * When SIGALRM timer is running, a select function will be * return -1 and EINTR after a Time Service signal hundler * is done. If the redial timer is not running and we are * trying to dial, poll with a 0 value timer. */ tp = (dial_up && RedialTimer.state != TIMER_RUNNING) ? &timeout : NULL; i = select(tun_in+10, &rfds, &wfds, &efds, tp); #endif if ( i == 0 ) { continue; } if ( i < 0 ) { if ( errno == EINTR ) { continue; /* Got SIGALRM, Do check a queue for dialing */ } perror("select"); break; } if ((netfd > 0 && FD_ISSET(netfd, &efds)) || FD_ISSET(modem, &efds)) { logprintf("Exception detected.\n"); break; } if (server > 0 && FD_ISSET(server, &rfds)) { #ifdef DEBUG logprintf("connected to client.\n"); #endif wfd = accept(server, (struct sockaddr *)&hisaddr, &ssize); if (netfd > 0) { write(wfd, "already in use.\n", 16); close(wfd); continue; } else netfd = wfd; if (dup2(netfd, 1) < 0) perror("dup2"); mode |= MODE_INTER; Greetings(); switch ( LocalAuthInit() ) { case NOT_FOUND: fprintf(stdout,LAUTH_M1); fprintf(stdout,LAUTH_M2); fflush(stdout); /* Fall down */ case VALID: VarLocalAuth = LOCAL_AUTH; break; default: break; } (void) IsInteractive(); Prompt(0); } if ((mode & MODE_INTER) && FD_ISSET(netfd, &rfds) && ((mode & MODE_AUTO) || pgroup == tcgetpgrp(0))) { /* something to read from tty */ ReadTty(); } if (modem) { if (FD_ISSET(modem, &wfds)) { /* ready to write into modem */ ModemStartOutput(modem); } if (FD_ISSET(modem, &rfds)) { /* something to read from modem */ if (LcpFsm.state <= ST_CLOSED) usleep(10000); n = read(modem, rbuff, sizeof(rbuff)); if ((mode & MODE_DIRECT) && n <= 0) { DownConnection(); } else LogDumpBuff(LOG_ASYNC, "ReadFromModem", rbuff, n); if (LcpFsm.state <= ST_CLOSED) { /* * In dedicated mode, we just discard input until LCP is started. */ if (!(mode & MODE_DEDICATED)) { cp = HdlcDetect(rbuff, n); if (cp) { /* * LCP packet is detected. Turn ourselves into packet mode. */ if (cp != rbuff) { write(1, rbuff, cp - rbuff); write(1, "\r\n", 2); } PacketMode(); #ifdef notdef AsyncInput(cp, n - (cp - rbuff)); #endif } else write(1, rbuff, n); } } else { if (n > 0) AsyncInput(rbuff, n); #ifdef notdef continue; /* THIS LINE RESULT AS POOR PERFORMANCE */ #endif } } } if (FD_ISSET(tun_in, &rfds)) { /* something to read from tun */ n = read(tun_in, rbuff, sizeof(rbuff)); if (n < 0) { perror("read from tun"); continue; } /* * Process on-demand dialup. Output packets are queued within tunnel * device until IPCP is opened. */ if (LcpFsm.state <= ST_CLOSED && (mode & MODE_AUTO)) { pri = PacketCheck(rbuff, n, FL_DIAL); if (pri >= 0) { if (mode & MODE_ALIAS) { PacketAliasOut(rbuff); n = ntohs(((struct ip *) rbuff)->ip_len); } IpEnqueue(pri, rbuff, n); dial_up = TRUE; /* XXX */ } continue; } pri = PacketCheck(rbuff, n, FL_OUT); if (pri >= 0) { if (mode & MODE_ALIAS) { PacketAliasOut(rbuff); n = ntohs(((struct ip *) rbuff)->ip_len); } IpEnqueue(pri, rbuff, n); } } } logprintf("job done.\n"); }