/* * sys-linux.c - System-dependent procedures for setting up * PPP interfaces on Linux systems * * Copyright (c) 1989 Carnegie Mellon University. * All rights reserved. * * 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 Carnegie Mellon University. The name of the * University 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. */ /* * TODO: */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "pppd.h" #include "ppp.h" #include "fsm.h" #include "ipcp.h" static int initdisc = -1; /* Initial TTY discipline */ static int prev_kdebugflag = 0; extern int kdebugflag; extern u_long netmask; #define MAX_IFS 32 /* prototypes */ void die __ARGS((int)); /* * SET_SA_FAMILY - set the sa_family field of a struct sockaddr, * if it exists. */ #define SET_SA_FAMILY(addr, family) \ memset ((char *) &(addr), '\0', sizeof(addr)); \ addr.sa_family = (family); /* * set_kdebugflag - Define the debugging level for the kernel */ int set_kdebugflag (int requested_level) { if (ioctl(fd, PPPIOCGDEBUG, &prev_kdebugflag) < 0) { syslog(LOG_ERR, "ioctl(PPPIOCGDEBUG): %m"); return (0); } if (prev_kdebugflag != requested_level) { if (ioctl(fd, PPPIOCSDEBUG, &requested_level) < 0) { syslog (LOG_ERR, "ioctl(PPPIOCSDEBUG): %m"); return (0); } syslog(LOG_INFO, "set kernel debugging level to %d", requested_level); } return (1); } /* * establish_ppp - Turn the serial port into a ppp interface. */ void establish_ppp (void) { int pppdisc = N_PPP; int sig = SIGIO; if (ioctl(fd, PPPIOCSINPSIG, &sig) == -1) { syslog(LOG_ERR, "ioctl(PPPIOCSINPSIG): %m"); die(1); } if (ioctl(fd, TIOCEXCL, 0) < 0) { syslog (LOG_WARNING, "ioctl(TIOCEXCL): %m"); } if (ioctl(fd, TIOCGETD, &initdisc) < 0) { syslog(LOG_ERR, "ioctl(TIOCGETD): %m"); die (1); } if (ioctl(fd, TIOCSETD, &pppdisc) < 0) { syslog(LOG_ERR, "ioctl(TIOCSETD): %m"); die (1); } if (ioctl(fd, PPPIOCGUNIT, &ifunit) < 0) { syslog(LOG_ERR, "ioctl(PPPIOCGUNIT): %m"); die (1); } set_kdebugflag (kdebugflag); } /* * disestablish_ppp - Restore the serial port to normal operation. * This shouldn't call die() because it's called from die(). */ void disestablish_ppp(void) { int x; char *s; if (initdisc >= 0) { set_kdebugflag (prev_kdebugflag); /* * Check whether the link seems not to be 8-bit clean. */ if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) == 0) { s = NULL; switch (~x & (SC_RCV_B7_0|SC_RCV_B7_1|SC_RCV_EVNP|SC_RCV_ODDP)) { case SC_RCV_B7_0: s = "bit 7 set to 1"; break; case SC_RCV_B7_1: s = "bit 7 set to 0"; break; case SC_RCV_EVNP: s = "odd parity"; break; case SC_RCV_ODDP: s = "even parity"; break; } if (s != NULL) { syslog(LOG_WARNING, "Serial link is not 8-bit clean:"); syslog(LOG_WARNING, "All received characters had %s", s); } } if (ioctl(fd, TIOCSETD, &initdisc) < 0) syslog(LOG_ERR, "ioctl(TIOCSETD): %m"); if (ioctl(fd, TIOCNXCL, 0) < 0) syslog (LOG_WARNING, "ioctl(TIOCNXCL): %m"); initdisc = -1; } } /* * output - Output PPP packet. */ void output (int unit, unsigned char *p, int len) { if (unit != 0) MAINDEBUG((LOG_WARNING, "output: unit != 0!")); if (debug) log_packet(p, len, "sent "); if (write(fd, p, len) < 0) { syslog(LOG_ERR, "write: %m"); die(1); } } /* * read_packet - get a PPP packet from the serial device. */ int read_packet (unsigned char *buf) { int len; len = read(fd, buf, MTU + DLLHEADERLEN); if (len < 0) { if (errno == EWOULDBLOCK) { #if 0 MAINDEBUG((LOG_DEBUG, "read(fd): EWOULDBLOCK")); #endif return -1; } syslog(LOG_ERR, "read(fd): %m"); die(1); } return len; } /* * ppp_send_config - configure the transmit characteristics of * the ppp interface. */ void ppp_send_config (int unit,int mtu,u_long asyncmap,int pcomp,int accomp) { u_int x; struct ifreq ifr; MAINDEBUG ((LOG_DEBUG, "send_config: mtu = %d\n", mtu)); strncpy(ifr.ifr_name, ifname, sizeof (ifr.ifr_name)); ifr.ifr_mtu = mtu; if (ioctl(s, SIOCSIFMTU, (caddr_t) &ifr) < 0) { syslog(LOG_ERR, "ioctl(SIOCSIFMTU): %m"); quit(); } MAINDEBUG ((LOG_DEBUG, "send_config: asyncmap = %lx\n", asyncmap)); if (ioctl(fd, PPPIOCSASYNCMAP, (caddr_t) &asyncmap) < 0) { syslog(LOG_ERR, "ioctl(PPPIOCSASYNCMAP): %m"); quit(); } if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) { syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m"); quit(); } x = pcomp ? x | SC_COMP_PROT : x & ~SC_COMP_PROT; x = accomp ? x | SC_COMP_AC : x & ~SC_COMP_AC; MAINDEBUG ((LOG_DEBUG, "send_config: flags = %x\n", x)); if (ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) { syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m"); quit(); } } /* * ppp_set_xaccm - set the extended transmit ACCM for the interface. */ void ppp_set_xaccm(unit, accm) int unit; ext_accm accm; { MAINDEBUG ((LOG_DEBUG, "set_xaccm: %08lx %08lx %08lx %08lx\n", accm[0], accm[1], accm[2], accm[3])); if (ioctl(fd, PPPIOCSXASYNCMAP, accm) < 0 && errno != ENOTTY) syslog(LOG_WARNING, "ioctl(set extended ACCM): %m"); } /* * ppp_recv_config - configure the receive-side characteristics of * the ppp interface. */ void ppp_recv_config (int unit,int mru,u_long asyncmap,int pcomp,int accomp) { u_int x; MAINDEBUG ((LOG_DEBUG, "recv_config: mru = %d\n", mru)); if (ioctl(fd, PPPIOCSMRU, (caddr_t) &mru) < 0) syslog(LOG_ERR, "ioctl(PPPIOCSMRU): %m"); MAINDEBUG ((LOG_DEBUG, "recv_config: asyncmap = %lx\n", asyncmap)); if (ioctl(fd, PPPIOCRASYNCMAP, (caddr_t) &asyncmap) < 0) { syslog(LOG_ERR, "ioctl(PPPIOCRASYNCMAP): %m"); quit(); } if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) { syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m"); quit(); } x = !accomp? x | SC_REJ_COMP_AC: x &~ SC_REJ_COMP_AC; MAINDEBUG ((LOG_DEBUG, "recv_config: flags = %x\n", x)); if (ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) { syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m"); quit(); } } /* * sifvjcomp - config tcp header compression */ int sifvjcomp (int u, int vjcomp, int cidcomp, int maxcid) { u_int x; if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) { syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m"); return 0; } x = vjcomp ? x | SC_COMP_TCP : x &~ SC_COMP_TCP; x = cidcomp ? x & ~SC_NO_TCP_CCID : x | SC_NO_TCP_CCID; if(ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) { syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m"); return 0; } if (vjcomp) { if (ioctl (fd, PPPIOCSMAXCID, (caddr_t) &maxcid) < 0) { syslog (LOG_ERR, "ioctl(PPPIOCSFLAGS): %m"); return 0; } } return 1; } /* * sifup - Config the interface up and enable IP packets to pass. */ int sifup (int u) { struct ifreq ifr; strncpy(ifr.ifr_name, ifname, sizeof (ifr.ifr_name)); if (ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) < 0) { syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m"); return 0; } ifr.ifr_flags |= (IFF_UP | IFF_POINTOPOINT); if (ioctl(s, SIOCSIFFLAGS, (caddr_t) &ifr) < 0) { syslog(LOG_ERR, "ioctl(SIOCSIFFLAGS): %m"); return 0; } return 1; } /* * sifdown - Config the interface down and disable IP. */ int sifdown (int u) { struct ifreq ifr; strncpy(ifr.ifr_name, ifname, sizeof (ifr.ifr_name)); if (ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) < 0) { syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m"); return 0; } ifr.ifr_flags &= ~IFF_UP; ifr.ifr_flags |= IFF_POINTOPOINT; if (ioctl(s, SIOCSIFFLAGS, (caddr_t) &ifr) < 0) { syslog(LOG_ERR, "ioctl(SIOCSIFFLAGS): %m"); return 0; } return 1; } /* * sifaddr - Config the interface IP addresses and netmask. */ int sifaddr (int unit, int our_adr, int his_adr, int net_mask) { struct ifreq ifr; struct rtentry rt; SET_SA_FAMILY (ifr.ifr_addr, AF_INET); SET_SA_FAMILY (ifr.ifr_dstaddr, AF_INET); SET_SA_FAMILY (ifr.ifr_netmask, AF_INET); strncpy (ifr.ifr_name, ifname, sizeof (ifr.ifr_name)); /* * Set our IP address */ ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr.s_addr = our_adr; if (ioctl(s, SIOCSIFADDR, (caddr_t) &ifr) < 0) { if (errno != EEXIST) syslog (LOG_ERR, "ioctl(SIOCAIFADDR): %m"); else syslog (LOG_WARNING, "ioctl(SIOCAIFADDR): Address already exists"); return (0); } /* * Set the gateway address */ ((struct sockaddr_in *) &ifr.ifr_dstaddr)->sin_addr.s_addr = his_adr; if (ioctl(s, SIOCSIFDSTADDR, (caddr_t) &ifr) < 0) { syslog (LOG_ERR, "ioctl(SIOCSIFDSTADDR): %m"); return (0); } /* * Set the netmask */ if (net_mask != 0) { ((struct sockaddr_in *) &ifr.ifr_netmask)->sin_addr.s_addr = net_mask; if (ioctl(s, SIOCSIFNETMASK, (caddr_t) &ifr) < 0) { syslog (LOG_ERR, "ioctl(SIOCSIFNETMASK): %m"); return (0); } } /* * Add the device route */ memset (&rt, '\0', sizeof (rt)); SET_SA_FAMILY (rt.rt_dst, AF_INET); SET_SA_FAMILY (rt.rt_gateway, AF_INET); rt.rt_dev = ifname; /* MJC */ ((struct sockaddr_in *) &rt.rt_gateway)->sin_addr.s_addr = 0; ((struct sockaddr_in *) &rt.rt_dst)->sin_addr.s_addr = his_adr; rt.rt_flags = RTF_UP | RTF_HOST; if (ioctl(s, SIOCADDRT, &rt) < 0) { syslog (LOG_ERR, "ioctl(SIOCADDRT) device route: %m"); return (0); } return 1; } /* * cifaddr - Clear the interface IP addresses, and delete routes * through the interface if possible. */ int cifaddr (int unit, int our_adr, int his_adr) { struct rtentry rt; /* * Delete the route through the device */ memset (&rt, '\0', sizeof (rt)); SET_SA_FAMILY (rt.rt_dst, AF_INET); SET_SA_FAMILY (rt.rt_gateway, AF_INET); rt.rt_dev = ifname; /* MJC */ ((struct sockaddr_in *) &rt.rt_gateway)->sin_addr.s_addr = 0; ((struct sockaddr_in *) &rt.rt_dst)->sin_addr.s_addr = his_adr; rt.rt_flags = RTF_UP | RTF_HOST; if (ioctl(s, SIOCDELRT, &rt) < 0) { syslog (LOG_ERR, "ioctl(SIOCDELRT) device route: %m"); return (0); } return 1; } /* * path_to_route - determine the path to the proc file system data */ FILE *route_fd = (FILE *) 0; static char route_buffer [100]; static char *path_to_route (void); static int open_route_table (void); static void close_route_table (void); static int read_route_table (struct rtentry *rt); static int defaultroute_exists (void); /* * path_to_route - find the path to the route tables in the proc file system */ static char *path_to_route (void) { struct mntent *mntent; FILE *fp; fp = fopen (MOUNTED, "r"); if (fp != 0) { while ((mntent = getmntent (fp)) != 0) { if (strcmp (mntent->mnt_type, MNTTYPE_IGNORE) == 0) continue; if (strcmp (mntent->mnt_type, "proc") == 0) { strncpy (route_buffer, mntent->mnt_dir, sizeof (route_buffer)-10); route_buffer [sizeof (route_buffer)-10] = '\0'; strcat (route_buffer, "/net/route"); fclose (fp); return (route_buffer); } } fclose (fp); } syslog (LOG_ERR, "proc file system not mounted"); return 0; } /* * open_route_table - open the interface to the route table */ static int open_route_table (void) { char *path; if (route_fd != (FILE *) 0) close_route_table(); path = path_to_route(); if (path == NULL) return 0; route_fd = fopen (path, "r"); if (route_fd == (FILE *) 0) { syslog (LOG_ERR, "can not open %s: %m", path); return 0; } /* read and discard the header line. */ if (fgets (route_buffer, sizeof (route_buffer), route_fd) == (char *) 0) { close_route_table(); return 0; } return 1; } /* * close_route_table - close the interface to the route table */ static void close_route_table (void) { if (route_fd != (FILE *) 0) { fclose (route_fd); route_fd = (FILE *) 0; } } /* * read_route_table - read the next entry from the route table */ static int read_route_table (struct rtentry *rt) { static char delims[] = " \t\n"; char *dev_ptr, *ptr, *dst_ptr, *gw_ptr, *flag_ptr; if (fgets (route_buffer, sizeof (route_buffer), route_fd) == (char *) 0) return 0; memset (rt, '\0', sizeof (struct rtentry)); dev_ptr = strtok (route_buffer, delims); /* interface name */ dst_ptr = strtok (NULL, delims); /* destination address */ gw_ptr = strtok (NULL, delims); /* gateway */ flag_ptr = strtok (NULL, delims); /* flags */ #if 0 ptr = strtok (NULL, delims); /* reference count */ ptr = strtok (NULL, delims); /* useage count */ ptr = strtok (NULL, delims); /* metric */ ptr = strtok (NULL, delims); /* mask */ #endif ((struct sockaddr_in *) &rt->rt_dst)->sin_addr.s_addr = strtoul (dst_ptr, NULL, 16); ((struct sockaddr_in *) &rt->rt_gateway)->sin_addr.s_addr = strtoul (gw_ptr, NULL, 16); rt->rt_flags = (short) strtoul (flag_ptr, NULL, 16); rt->rt_dev = dev_ptr; return 1; } /* * defaultroute_exists - determine if there is a default route */ static int defaultroute_exists (void) { struct rtentry rt; int result = 0; if (!open_route_table()) return 0; while (read_route_table(&rt) != 0) { if (rt.rt_flags & RTF_UP == 0) continue; if (((struct sockaddr_in *) &rt.rt_dst)->sin_addr.s_addr == 0L) { syslog (LOG_ERR, "ppp not replacing existing default route to %s[%s]", rt.rt_dev, inet_ntoa (((struct sockaddr_in *) &rt.rt_gateway)-> sin_addr.s_addr)); result = 1; break; } } close_route_table(); return result; } /* * sifdefaultroute - assign a default route through the address given. */ int sifdefaultroute (int unit, int gateway) { struct rtentry rt; if (defaultroute_exists()) return 0; memset (&rt, '\0', sizeof (rt)); SET_SA_FAMILY (rt.rt_dst, AF_INET); SET_SA_FAMILY (rt.rt_gateway, AF_INET); ((struct sockaddr_in *) &rt.rt_gateway)->sin_addr.s_addr = gateway; rt.rt_flags = RTF_UP | RTF_GATEWAY; if (ioctl(s, SIOCADDRT, &rt) < 0) { syslog (LOG_ERR, "default route ioctl(SIOCADDRT): %m"); return 0; } return 1; } /* * cifdefaultroute - delete a default route through the address given. */ int cifdefaultroute (int unit, int gateway) { struct rtentry rt; SET_SA_FAMILY (rt.rt_dst, AF_INET); SET_SA_FAMILY (rt.rt_gateway, AF_INET); ((struct sockaddr_in *) &rt.rt_gateway)->sin_addr.s_addr = gateway; rt.rt_flags = RTF_UP | RTF_GATEWAY; if (ioctl(s, SIOCDELRT, &rt) < 0) { syslog (LOG_ERR, "default route ioctl(SIOCDELRT): %m"); return 0; } return 1; } /* * sifproxyarp - Make a proxy ARP entry for the peer. */ int sifproxyarp (int unit, u_long his_adr) { struct arpreq arpreq; memset (&arpreq, '\0', sizeof(arpreq)); /* * Get the hardware address of an interface on the same subnet * as our local address. */ if (!get_ether_addr(his_adr, &arpreq.arp_ha)) { syslog(LOG_ERR, "Cannot determine ethernet address for proxy ARP"); return 0; } SET_SA_FAMILY(arpreq.arp_pa, AF_INET); ((struct sockaddr_in *) &arpreq.arp_pa)->sin_addr.s_addr = his_adr; arpreq.arp_flags = ATF_PERM | ATF_PUBL; if (ioctl(s, SIOCSARP, (caddr_t)&arpreq) < 0) { syslog(LOG_ERR, "ioctl(SIOCSARP): %m"); return 0; } return 1; } /* * cifproxyarp - Delete the proxy ARP entry for the peer. */ int cifproxyarp (int unit, u_long his_adr) { struct arpreq arpreq; memset (&arpreq, '\0', sizeof(arpreq)); SET_SA_FAMILY(arpreq.arp_pa, AF_INET); ((struct sockaddr_in *) &arpreq.arp_pa)->sin_addr.s_addr = his_adr; if (ioctl(s, SIOCDARP, (caddr_t)&arpreq) < 0) { syslog(LOG_WARNING, "ioctl(SIOCDARP): %m"); return 0; } return 1; } /* * get_ether_addr - get the hardware address of an interface on the * the same subnet as ipaddr. */ int get_ether_addr (u_long ipaddr, struct sockaddr *hwaddr) { struct ifreq *ifr, *ifend, *ifp; int i; u_long ina, mask; struct sockaddr_dl *dla; struct ifreq ifreq; struct ifconf ifc; struct ifreq ifs[MAX_IFS]; ifc.ifc_len = sizeof(ifs); ifc.ifc_req = ifs; if (ioctl(s, SIOCGIFCONF, &ifc) < 0) { syslog(LOG_ERR, "ioctl(SIOCGIFCONF): %m"); return 0; } MAINDEBUG ((LOG_DEBUG, "proxy arp: scanning %d interfaces for IP %s", ifc.ifc_len / sizeof(struct ifreq), ip_ntoa(ipaddr))); /* * Scan through looking for an interface with an Internet * address on the same subnet as `ipaddr'. */ ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq)); for (ifr = ifc.ifc_req; ifr < ifend; ifr++) { if (ifr->ifr_addr.sa_family == AF_INET) { ina = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr; strncpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name)); MAINDEBUG ((LOG_DEBUG, "proxy arp: examining interface %s", ifreq.ifr_name)); /* * Check that the interface is up, and not point-to-point * or loopback. */ if (ioctl(s, SIOCGIFFLAGS, &ifreq) < 0) continue; if ((ifreq.ifr_flags & (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT|IFF_LOOPBACK|IFF_NOARP)) != (IFF_UP|IFF_BROADCAST)) continue; /* * Get its netmask and check that it's on the right subnet. */ if (ioctl(s, SIOCGIFNETMASK, &ifreq) < 0) continue; mask = ((struct sockaddr_in *) &ifreq.ifr_addr)->sin_addr.s_addr; MAINDEBUG ((LOG_DEBUG, "proxy arp: interface addr %s mask %lx", ip_ntoa(ina), ntohl(mask))); if (((ipaddr ^ ina) & mask) != 0) continue; break; } } if (ifr >= ifend) return 0; syslog(LOG_INFO, "found interface %s for proxy arp", ifreq.ifr_name); /* * Now get the hardware address. */ if (ioctl (s, SIOCGIFHWADDR, &ifreq) < 0) { syslog(LOG_ERR, "SIOCGIFHWADDR(%s): %m", ifreq.ifr_name); return 0; } hwaddr->sa_family = ARPHRD_ETHER; #ifndef old_ifr_hwaddr memcpy (&hwaddr->sa_data, &ifreq.ifr_hwaddr, ETH_ALEN); #else memcpy (&hwaddr->sa_data, &ifreq.ifr_hwaddr.sa_data, ETH_ALEN); #endif MAINDEBUG ((LOG_DEBUG, "proxy arp: found hwaddr %02x:%02x:%02x:%02x:%02x:%02x", (int) ((unsigned char *) &hwaddr->sa_data)[0], (int) ((unsigned char *) &hwaddr->sa_data)[1], (int) ((unsigned char *) &hwaddr->sa_data)[2], (int) ((unsigned char *) &hwaddr->sa_data)[3], (int) ((unsigned char *) &hwaddr->sa_data)[4], (int) ((unsigned char *) &hwaddr->sa_data)[5])); return 1; } /* * ppp_available - check whether the system has any ppp interfaces * (in fact we check whether we can do an ioctl on ppp0). */ int ppp_available(void) { int s, ok; struct ifreq ifr; s = socket(AF_INET, SOCK_DGRAM, 0); if (s < 0) return 1; /* can't tell - maybe we're not root */ strncpy(ifr.ifr_name, "ppp0", sizeof (ifr.ifr_name)); ok = ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) >= 0; close(s); return ok; } int logwtmp(line, name, host) char *line, *name, *host; { struct utmp ut; memset (&ut, 0, sizeof (ut)); (void)strncpy(ut.ut_line, line, sizeof(ut.ut_line)); (void)strncpy(ut.ut_name, name, sizeof(ut.ut_name)); (void)strncpy(ut.ut_host, host, sizeof(ut.ut_host)); (void)time(&ut.ut_time); pututline (&ut); /* Write the line to the proper place */ endutent(); /* Indicate operation is complete */ }