/* * interface.c -- implements fetchmail 'interface' and 'monitor' commands * * This module was implemented by George M. Sipe * or and is: * * Copyright (c) 1996,1997 by George M. Sipe - ALL RIGHTS RESERVED * * This is free software; you can redistribute it and/or modify it under * the terms of the GNU General Public License as published by the Free * Software Foundation; version 2, or (at your option) any later version. */ #ifdef linux #include "config.h" #include #include #if defined(STDC_HEADERS) #include #endif #if defined(HAVE_UNISTD_H) #include #endif #include #include #include #include "config.h" #include "fetchmail.h" typedef struct { struct in_addr addr, dstaddr, netmask; int rx_packets, tx_packets; } ifinfo_t; struct interface_pair_s { struct in_addr interface_address; struct in_addr interface_mask; } *interface_pair; static int _get_ifinfo_(int socket_fd, FILE *stats_file, const char *ifname, ifinfo_t *ifinfo) /* get active network interface information - return non-zero upon success */ { int namelen = strlen(ifname); struct ifreq request; char *cp, buffer[256]; /* initialize result */ memset((char *) ifinfo, 0, sizeof(ifinfo_t)); /* see if the interface is up */ strcpy(request.ifr_name, ifname); if (ioctl(socket_fd, SIOCGIFFLAGS, &request) < 0) return(FALSE); if (!(request.ifr_flags & IFF_RUNNING)) return(FALSE); /* get the IP address */ strcpy(request.ifr_name, ifname); if (ioctl(socket_fd, SIOCGIFADDR, &request) < 0) return(FALSE); ifinfo->addr = ((struct sockaddr_in *) (&request.ifr_addr))->sin_addr; /* get the PPP destination IP address */ strcpy(request.ifr_name, ifname); if (ioctl(socket_fd, SIOCGIFDSTADDR, &request) >= 0) ifinfo->dstaddr = ((struct sockaddr_in *) (&request.ifr_dstaddr))->sin_addr; /* get the netmask */ strcpy(request.ifr_name, ifname); if (ioctl(socket_fd, SIOCGIFNETMASK, &request) >= 0) ifinfo->netmask = ((struct sockaddr_in *) (&request.ifr_netmask))->sin_addr; /* get the packet I/O counts */ while (fgets(buffer, sizeof(buffer) - 1, stats_file)) { for (cp = buffer; *cp && *cp == ' '; ++cp); if (!strncmp(cp, ifname, namelen) && cp[namelen] == ':') { cp += namelen + 1; sscanf(cp, "%d %*d %*d %*d %*d %d %*d %*d %*d %*d %*d", &ifinfo->rx_packets, &ifinfo->tx_packets); return(TRUE); } } return(FALSE); } static int get_ifinfo(const char *ifname, ifinfo_t *ifinfo) { int socket_fd = socket(AF_INET, SOCK_DGRAM, 0); FILE *stats_file = fopen("/proc/net/dev", "r"); int result; if (socket_fd < 0 || !stats_file) result = FALSE; else result = _get_ifinfo_(socket_fd, stats_file, ifname, ifinfo); if (socket_fd >= 0) close(socket_fd); if (stats_file) fclose(stats_file); return(result); } void interface_parse(char *buf, struct hostdata *hp) /* parse 'interface' specification */ { char *cp1, *cp2; /* find and isolate just the IP address */ if (!(cp1 = strchr(buf, '/'))) (void) error(PS_SYNTAX, 0, "missing IP interface address"); *cp1++ = '\000'; hp->interface = xstrdup(buf); /* find and isolate just the netmask */ if (!(cp2 = strchr(cp1, '/'))) cp2 = "255.255.255.255"; else *cp2++ = '\000'; /* convert IP address and netmask */ hp->interface_pair = (struct interface_pair_s *)xmalloc(sizeof(struct interface_pair_s)); if (!inet_aton(cp1, &hp->interface_pair->interface_address)) (void) error(PS_SYNTAX, 0, "invalid IP interface address"); if (!inet_aton(cp2, &hp->interface_pair->interface_mask)) (void) error(PS_SYNTAX, 0, "invalid IP interface mask"); /* apply the mask now to the IP address (range) required */ hp->interface_pair->interface_address.s_addr &= hp->interface_pair->interface_mask.s_addr; return; } void interface_note_activity(struct hostdata *hp) /* save interface I/O counts */ { ifinfo_t ifinfo; struct query *ctl; /* if not monitoring link, all done */ if (!hp->monitor) return; /* get the current I/O stats for the monitored link */ if (get_ifinfo(hp->monitor, &ifinfo)) /* update this and preceeding host entries using the link (they were already set during this pass but the I/O count has now changed and they need to be re-updated) */ for (ctl = querylist; ctl; ctl = ctl->next) { if (!strcmp(hp->monitor, ctl->server.monitor)) ctl->server.monitor_io = ifinfo.rx_packets + ifinfo.tx_packets; /* do NOT update host entries following this one */ if (&ctl->server == hp) break; } #ifdef ACTIVITY_DEBUG (void) error(0, 0, "activity on %s -noted- as %d", hp->monitor, hp->monitor_io); #endif } int interface_approve(struct hostdata *hp) /* return TRUE if OK to poll, FALSE otherwise */ { ifinfo_t ifinfo; /* check interface IP address (range), if specified */ if (hp->interface) { /* get interface info */ if (!get_ifinfo(hp->interface, &ifinfo)) { (void) error(0, 0, "skipping poll of %s, %s down", hp->pollname, hp->interface); return(FALSE); } /* check the IP address (range) */ if ((ifinfo.addr.s_addr & hp->interface_pair->interface_mask.s_addr) != hp->interface_pair->interface_address.s_addr) { (void) error(0, 0, "skipping poll of %s, %s IP address excluded", hp->pollname, hp->interface); return(FALSE); } } /* if not monitoring link, all done */ if (!hp->monitor) return(TRUE); #ifdef ACTIVITY_DEBUG (void) error(0, 0, "activity on %s checked as %d", hp->monitor, hp->monitor_io); #endif /* if monitoring, check link for activity if it is up */ if (get_ifinfo(hp->monitor, &ifinfo) && hp->monitor_io == ifinfo.rx_packets + ifinfo.tx_packets) { (void) error(0, 0, "skipping poll of %s, %s inactive", hp->pollname, hp->monitor); return(FALSE); } return(TRUE); } #endif /* linux */