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/* $OpenBSD: npppd_subr.c,v 1.18 2016/04/05 21:24:02 krw Exp $ */ |
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/*- |
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* Copyright (c) 2009 Internet Initiative Japan Inc. |
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* All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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*/ |
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/**@file |
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* This file provides helper functions for npppd. |
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*/ |
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <netinet/in.h> |
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#include <netinet/ip.h> |
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#include <netinet/udp.h> |
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#include <netinet/tcp.h> |
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#include <net/route.h> |
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#include <net/if_dl.h> |
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#include <net/if.h> |
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#include <ifaddrs.h> |
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#include <arpa/inet.h> |
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#include <stdlib.h> |
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#include <fcntl.h> |
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#include <stdio.h> |
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#include <syslog.h> |
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#include <stddef.h> |
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#include <unistd.h> |
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#include <errno.h> |
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#include <ctype.h> |
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#include <string.h> |
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#include <resolv.h> |
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#include "debugutil.h" |
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#include "addr_range.h" |
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#include "npppd_defs.h" |
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#include "npppd_subr.h" |
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#include "privsep.h" |
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#define MINIMUM(a, b) (((a) < (b)) ? (a) : (b)) |
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static u_int16_t route_seq = 0; |
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static int in_route0(int, struct in_addr *, struct in_addr *, struct in_addr *, int, const char *, uint32_t); |
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#define ROUNDUP(a) \ |
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((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) |
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static const char * |
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skip_space(const char *s) |
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{ |
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const char *r; |
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for (r = s; *r != '\0' && isspace((unsigned char)*r); r++) |
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;; /* skip */ |
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return r; |
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} |
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/** |
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* Read and store IPv4 address of name server from resolv.conf. |
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* The path of resolv.conf is taken from _PATH_RESCONF in resolv.h. |
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*/ |
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int |
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load_resolv_conf(struct in_addr *pri, struct in_addr *sec) |
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{ |
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FILE *filep; |
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int i; |
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struct in_addr *addr; |
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char *ap, *line, buf[BUFSIZ]; |
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pri->s_addr = INADDR_NONE; |
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sec->s_addr = INADDR_NONE; |
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filep = NULL; |
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if ((filep = priv_fopen(_PATH_RESCONF)) == NULL) |
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return 1; |
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i = 0; |
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while (fgets(buf, sizeof(buf), filep) != NULL) { |
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line = (char *)skip_space(buf); |
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if (strncmp(line, "nameserver", 10) != 0) |
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continue; |
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line += 10; |
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if (!isspace((unsigned char)*line)) |
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continue; |
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while ((ap = strsep(&line, " \t\r\n")) != NULL) { |
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if (*ap == '\0') |
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continue; |
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if (i == 0) |
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addr = pri; |
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else |
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addr = sec; |
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if (inet_aton(ap, addr) != 1) { |
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/* |
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* FIXME: If configured IPv6, it may have IPv6 |
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* FIXME: address. For the present, continue. |
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*/ |
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continue; |
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} |
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addr->s_addr = addr->s_addr; |
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if (++i >= 2) |
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goto end_loop; |
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} |
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} |
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end_loop: |
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if (filep != NULL) |
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fclose(filep); |
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return 0; |
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} |
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/* Add and delete routing entry. */ |
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static int |
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in_route0(int type, struct in_addr *dest, struct in_addr *mask, |
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struct in_addr *gate, int mtu, const char *ifname, uint32_t rtm_flags) |
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{ |
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struct rt_msghdr *rtm; |
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struct sockaddr_in sdest, smask, sgate; |
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struct sockaddr_dl *sdl; |
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char dl_buf[512]; /* enough size */ |
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char *cp, buf[sizeof(*rtm) + sizeof(struct sockaddr_in) * 3 + |
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sizeof(dl_buf) + 128]; |
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const char *strtype; |
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int rval, flags, sock; |
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sock = -1; |
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ASSERT(type == RTM_ADD || type == RTM_DELETE); |
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if(type == RTM_ADD) |
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strtype = "RTM_ADD"; |
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else |
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strtype = "RTM_DELETE"; |
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memset(buf, 0, sizeof(buf)); |
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memset(&sdest, 0, sizeof(sdest)); |
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memset(&smask, 0, sizeof(smask)); |
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memset(&sgate, 0, sizeof(sgate)); |
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memset(&dl_buf, 0, sizeof(dl_buf)); |
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sdl = (struct sockaddr_dl *)dl_buf; |
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sdest.sin_addr = *dest; |
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if (mask != NULL) |
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smask.sin_addr = *mask; |
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if (gate != NULL) |
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sgate.sin_addr = *gate; |
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sdest.sin_family = smask.sin_family = sgate.sin_family = AF_INET; |
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sdest.sin_len = smask.sin_len = sgate.sin_len = sizeof(sgate); |
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rtm = (struct rt_msghdr *)buf; |
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rtm->rtm_version = RTM_VERSION; |
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rtm->rtm_type = type; |
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rtm->rtm_flags = rtm_flags; |
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if (gate != NULL) |
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rtm->rtm_flags |= RTF_GATEWAY; |
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if (mask == NULL) |
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rtm->rtm_flags |= RTF_HOST; |
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if (type == RTM_ADD && mtu > 0) { |
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rtm->rtm_inits = RTV_MTU; |
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rtm->rtm_rmx.rmx_mtu = mtu; |
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} |
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185 |
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if (type == RTM_ADD) |
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rtm->rtm_flags |= RTF_UP; |
187 |
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rtm->rtm_addrs = RTA_DST; |
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if (gate != NULL) |
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rtm->rtm_addrs |= RTA_GATEWAY; |
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if (mask != NULL) |
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rtm->rtm_addrs |= RTA_NETMASK; |
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#ifdef RTA_IFP |
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if (ifname != NULL) |
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rtm->rtm_addrs |= RTA_IFP; |
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#endif |
197 |
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rtm->rtm_pid = getpid(); |
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route_seq = ((route_seq + 1)&0x0000ffff); |
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rtm->rtm_seq = route_seq; |
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cp = (char *)rtm; |
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cp += ROUNDUP(sizeof(*rtm)); |
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memcpy(cp, &sdest, sdest.sin_len); |
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cp += ROUNDUP(sdest.sin_len); |
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if (gate != NULL) { |
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memcpy(cp, &sgate, sgate.sin_len); |
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cp += ROUNDUP(sgate.sin_len); |
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} |
211 |
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if (mask != NULL) { |
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memcpy(cp, &smask, smask.sin_len); |
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cp += ROUNDUP(smask.sin_len); |
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} |
215 |
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#ifdef RTA_IFP |
216 |
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if (ifname != NULL) { |
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strlcpy(sdl->sdl_data, ifname, IFNAMSIZ); |
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sdl->sdl_family = AF_LINK; |
219 |
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sdl->sdl_len = offsetof(struct sockaddr_dl, sdl_data) +IFNAMSIZ; |
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sdl->sdl_index = if_nametoindex(ifname); |
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memcpy(cp, sdl, sdl->sdl_len); |
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cp += ROUNDUP(sdl->sdl_len); |
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} |
224 |
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#endif |
225 |
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226 |
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rtm->rtm_msglen = cp - buf; |
227 |
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228 |
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if ((sock = priv_socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC)) < 0) { |
229 |
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log_printf(LOG_ERR, "socket() failed in %s() on %s : %m", |
230 |
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__func__, strtype); |
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goto fail; |
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} |
233 |
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234 |
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if ((flags = fcntl(sock, F_GETFL)) < 0) { |
235 |
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log_printf(LOG_ERR, "fcntl(,F_GETFL) failed on %s : %m", |
236 |
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__func__); |
237 |
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goto fail; |
238 |
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} |
239 |
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240 |
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if (fcntl(sock, F_SETFL, flags | O_NONBLOCK) < 0) { |
241 |
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log_printf(LOG_ERR, "fcntl(,F_SETFL) failed on %s : %m", |
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__func__); |
243 |
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goto fail; |
244 |
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} |
245 |
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246 |
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if ((rval = priv_send(sock, buf, rtm->rtm_msglen, 0)) <= 0) { |
247 |
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if ((type == RTM_DELETE && errno == ESRCH) || |
248 |
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(type == RTM_ADD && errno == EEXIST)) { |
249 |
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log_printf(LOG_DEBUG, |
250 |
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"write() failed in %s on %s : %m", __func__, |
251 |
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strtype); |
252 |
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} else { |
253 |
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log_printf(LOG_WARNING, |
254 |
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"write() failed in %s on %s : %m", __func__, |
255 |
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strtype); |
256 |
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} |
257 |
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goto fail; |
258 |
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} |
259 |
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260 |
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close(sock); |
261 |
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262 |
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return 0; |
263 |
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264 |
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fail: |
265 |
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if (sock >= 0) |
266 |
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close(sock); |
267 |
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268 |
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return 1; |
269 |
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} |
270 |
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271 |
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/** Add host routing entry. */ |
272 |
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int |
273 |
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in_host_route_add(struct in_addr *dest, struct in_addr *gate, |
274 |
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const char *ifname, int mtu) |
275 |
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{ |
276 |
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return in_route0(RTM_ADD, dest, NULL, gate, mtu, ifname, 0); |
277 |
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} |
278 |
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279 |
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/** Delete host routing entry. */ |
280 |
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int |
281 |
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in_host_route_delete(struct in_addr *dest, struct in_addr *gate) |
282 |
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{ |
283 |
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return in_route0(RTM_DELETE, dest, NULL, gate, 0, NULL, 0); |
284 |
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} |
285 |
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286 |
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/** Add network routing entry. */ |
287 |
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int |
288 |
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in_route_add(struct in_addr *dest, struct in_addr *mask, struct in_addr *gate, |
289 |
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const char *ifname, uint32_t rtm_flags, int mtu) |
290 |
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{ |
291 |
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return in_route0(RTM_ADD, dest, mask, gate, mtu, ifname, rtm_flags); |
292 |
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} |
293 |
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294 |
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/** Delete network routing entry. */ |
295 |
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int |
296 |
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in_route_delete(struct in_addr *dest, struct in_addr *mask, |
297 |
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struct in_addr *gate, uint32_t rtm_flags) |
298 |
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{ |
299 |
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return in_route0(RTM_DELETE, dest, mask, gate, 0, NULL, rtm_flags); |
300 |
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} |
301 |
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302 |
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/** |
303 |
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* Check whether a packet should reset idle timer |
304 |
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* Returns 1 to don't reset timer (i.e. the packet is "idle" packet) |
305 |
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*/ |
306 |
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int |
307 |
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ip_is_idle_packet(const struct ip * pip, int len) |
308 |
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{ |
309 |
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u_int16_t ip_off; |
310 |
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const struct udphdr *uh; |
311 |
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312 |
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/* |
313 |
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* Fragmented packet is not idle packet. |
314 |
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* (Long packet which needs to fragment is not idle packet.) |
315 |
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*/ |
316 |
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ip_off = ntohs(pip->ip_off); |
317 |
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if ((ip_off & IP_MF) || ((ip_off & IP_OFFMASK) != 0)) |
318 |
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return 0; |
319 |
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|
320 |
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switch (pip->ip_p) { |
321 |
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case IPPROTO_IGMP: |
322 |
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return 1; |
323 |
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case IPPROTO_ICMP: |
324 |
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/* Is length enough? */ |
325 |
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if (pip->ip_hl * 4 + 8 > len) |
326 |
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return 1; |
327 |
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328 |
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switch (((unsigned char *) pip)[pip->ip_hl * 4]) { |
329 |
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case 0: /* Echo Reply */ |
330 |
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case 8: /* Echo Request */ |
331 |
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return 0; |
332 |
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default: |
333 |
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return 1; |
334 |
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} |
335 |
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case IPPROTO_UDP: |
336 |
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case IPPROTO_TCP: |
337 |
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/* |
338 |
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* The place of port number of UDP and TCP is the same, |
339 |
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* so can be shared. |
340 |
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*/ |
341 |
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uh = (const struct udphdr *) (((const char *) pip) + |
342 |
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(pip->ip_hl * 4)); |
343 |
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|
344 |
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/* Is length enough? */ |
345 |
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if (pip->ip_hl * 4 + sizeof(struct udphdr) > len) |
346 |
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return 1; |
347 |
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|
348 |
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switch (ntohs(uh->uh_sport)) { |
349 |
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case 53: /* DOMAIN */ |
350 |
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case 67: /* BOOTPS */ |
351 |
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case 68: /* BOOTPC */ |
352 |
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case 123: /* NTP */ |
353 |
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case 137: /* NETBIOS-NS */ |
354 |
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case 520: /* RIP */ |
355 |
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return 1; |
356 |
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} |
357 |
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switch (ntohs(uh->uh_dport)) { |
358 |
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case 53: /* DOMAIN */ |
359 |
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case 67: /* BOOTPS */ |
360 |
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case 68: /* BOOTPC */ |
361 |
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case 123: /* NTP */ |
362 |
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case 137: /* NETBIOS-NS */ |
363 |
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case 520: /* RIP */ |
364 |
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return 1; |
365 |
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} |
366 |
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return 0; |
367 |
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default: |
368 |
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return 0; |
369 |
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} |
370 |
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} |
371 |
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|
372 |
|
|
/*********************************************************************** |
373 |
|
|
* Add and delete routing entry for the pool address. |
374 |
|
|
***********************************************************************/ |
375 |
|
|
void |
376 |
|
|
in_addr_range_add_route(struct in_addr_range *range) |
377 |
|
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{ |
378 |
|
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struct in_addr_range *range0; |
379 |
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struct in_addr dest, mask, loop; |
380 |
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|
|
381 |
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for (range0 = range; range0 != NULL; range0 = range0->next){ |
382 |
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dest.s_addr = htonl(range0->addr); |
383 |
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mask.s_addr = htonl(range0->mask); |
384 |
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loop.s_addr = htonl(INADDR_LOOPBACK); |
385 |
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in_route_add(&dest, &mask, &loop, LOOPBACK_IFNAME, |
386 |
|
|
RTF_BLACKHOLE, 0); |
387 |
|
|
} |
388 |
|
|
log_printf(LOG_INFO, "Added routes for pooled addresses"); |
389 |
|
|
} |
390 |
|
|
|
391 |
|
|
void |
392 |
|
|
in_addr_range_delete_route(struct in_addr_range *range) |
393 |
|
|
{ |
394 |
|
|
struct in_addr_range *range0; |
395 |
|
|
struct in_addr dest, mask, loop; |
396 |
|
|
|
397 |
|
|
for (range0 = range; range0 != NULL; range0 = range0->next){ |
398 |
|
|
dest.s_addr = htonl(range0->addr); |
399 |
|
|
mask.s_addr = htonl(range0->mask); |
400 |
|
|
loop.s_addr = htonl(INADDR_LOOPBACK); |
401 |
|
|
|
402 |
|
|
in_route_delete(&dest, &mask, &loop, RTF_BLACKHOLE); |
403 |
|
|
} |
404 |
|
|
log_printf(LOG_NOTICE, "Deleted routes for pooled addresses"); |
405 |
|
|
} |
406 |
|
|
|
407 |
|
|
|
408 |
|
|
/* GETSHORT is also defined in #inlude <arpa/nameser_compat.h>. */ |
409 |
|
|
#undef GETCHAR |
410 |
|
|
#undef GETSHORT |
411 |
|
|
#undef PUTSHORT |
412 |
|
|
|
413 |
|
|
#define GETCHAR(c, cp) { (c) = *(cp)++; } |
414 |
|
|
#define GETSHORT(s, cp) { \ |
415 |
|
|
(s) = *(cp)++ << 8; \ |
416 |
|
|
(s) |= *(cp)++; \ |
417 |
|
|
} |
418 |
|
|
#define PUTSHORT(s, cp) { \ |
419 |
|
|
*(cp)++ = (u_char) ((s) >> 8); \ |
420 |
|
|
*(cp)++ = (u_char) (s); \ |
421 |
|
|
} |
422 |
|
|
#define TCP_OPTLEN_IN_SEGMENT 12 /* timestamp option and padding */ |
423 |
|
|
#define MAXMSS(mtu) (mtu - sizeof(struct ip) - sizeof(struct tcphdr) - \ |
424 |
|
|
TCP_OPTLEN_IN_SEGMENT) |
425 |
|
|
|
426 |
|
|
/* adapted from FreeBSD:src/usr.sbin/ppp/tcpmss.c */ |
427 |
|
|
/* |
428 |
|
|
* Copyright (c) 2000 Ruslan Ermilov and Brian Somers <brian@Awfulhak.org> |
429 |
|
|
* All rights reserved. |
430 |
|
|
* |
431 |
|
|
* Redistribution and use in source and binary forms, with or without |
432 |
|
|
* modification, are permitted provided that the following conditions |
433 |
|
|
* are met: |
434 |
|
|
* 1. Redistributions of source code must retain the above copyright |
435 |
|
|
* notice, this list of conditions and the following disclaimer. |
436 |
|
|
* 2. Redistributions in binary form must reproduce the above copyright |
437 |
|
|
* notice, this list of conditions and the following disclaimer in the |
438 |
|
|
* documentation and/or other materials provided with the distribution. |
439 |
|
|
* |
440 |
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
441 |
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
442 |
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
443 |
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
444 |
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
445 |
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
446 |
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
447 |
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
448 |
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
449 |
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
450 |
|
|
* SUCH DAMAGE. |
451 |
|
|
* |
452 |
|
|
* $FreeBSD: src/usr.sbin/ppp/tcpmss.c,v 1.1.4.3 2001/07/19 11:39:54 brian Exp $ |
453 |
|
|
*/ |
454 |
|
|
|
455 |
|
|
/* |
456 |
|
|
* The following macro is used to update an internet checksum. "acc" is a |
457 |
|
|
* 32-bit accumulation of all the changes to the checksum (adding in old |
458 |
|
|
* 16-bit words and subtracting out new words), and "cksum" is the checksum |
459 |
|
|
* value to be updated. |
460 |
|
|
*/ |
461 |
|
|
#define ADJUST_CHECKSUM(acc, cksum) { \ |
462 |
|
|
acc += cksum; \ |
463 |
|
|
if (acc < 0) { \ |
464 |
|
|
acc = -acc; \ |
465 |
|
|
acc = (acc >> 16) + (acc & 0xffff); \ |
466 |
|
|
acc += acc >> 16; \ |
467 |
|
|
cksum = (u_short) ~acc; \ |
468 |
|
|
} else { \ |
469 |
|
|
acc = (acc >> 16) + (acc & 0xffff); \ |
470 |
|
|
acc += acc >> 16; \ |
471 |
|
|
cksum = (u_short) acc; \ |
472 |
|
|
} \ |
473 |
|
|
} |
474 |
|
|
|
475 |
|
|
/** |
476 |
|
|
* Adjust mss to make IP packet be shorter than or equal MTU. |
477 |
|
|
* |
478 |
|
|
* @param pktp pointer that indicates IP packet |
479 |
|
|
* @param lpktp length |
480 |
|
|
* @param mtu MTU |
481 |
|
|
*/ |
482 |
|
|
int |
483 |
|
|
adjust_tcp_mss(u_char *pktp, int lpktp, int mtu) |
484 |
|
|
{ |
485 |
|
|
int opt, optlen, acc, ip_off, mss, maxmss; |
486 |
|
|
struct ip *pip; |
487 |
|
|
struct tcphdr *th; |
488 |
|
|
|
489 |
|
|
if (lpktp < sizeof(struct ip) + sizeof(struct tcphdr)) |
490 |
|
|
return 1; |
491 |
|
|
|
492 |
|
|
pip = (struct ip *)pktp; |
493 |
|
|
ip_off = ntohs(pip->ip_off); |
494 |
|
|
|
495 |
|
|
/* exclude non-TCP packet or fragmented packet. */ |
496 |
|
|
if (pip->ip_p != IPPROTO_TCP || (ip_off & IP_MF) != 0 || |
497 |
|
|
(ip_off & IP_OFFMASK) != 0) |
498 |
|
|
return 0; |
499 |
|
|
|
500 |
|
|
pktp += pip->ip_hl << 2; |
501 |
|
|
lpktp -= pip->ip_hl << 2; |
502 |
|
|
|
503 |
|
|
/* broken packet */ |
504 |
|
|
if (sizeof(struct tcphdr) > lpktp) |
505 |
|
|
return 1; |
506 |
|
|
|
507 |
|
|
th = (struct tcphdr *)pktp; |
508 |
|
|
/* MSS is selected only from SYN segment. (See RFC 793) */ |
509 |
|
|
if ((th->th_flags & TH_SYN) == 0) |
510 |
|
|
return 0; |
511 |
|
|
|
512 |
|
|
lpktp = MINIMUM(th->th_off << 4, lpktp); |
513 |
|
|
|
514 |
|
|
pktp += sizeof(struct tcphdr); |
515 |
|
|
lpktp -= sizeof(struct tcphdr); |
516 |
|
|
|
517 |
|
|
while (lpktp >= TCPOLEN_MAXSEG) { |
518 |
|
|
GETCHAR(opt, pktp); |
519 |
|
|
switch (opt) { |
520 |
|
|
case TCPOPT_MAXSEG: |
521 |
|
|
GETCHAR(optlen, pktp); |
522 |
|
|
GETSHORT(mss, pktp); |
523 |
|
|
maxmss = MAXMSS(mtu); |
524 |
|
|
if (mss > maxmss) { |
525 |
|
|
pktp-=2; |
526 |
|
|
PUTSHORT(maxmss, pktp); |
527 |
|
|
acc = htons(mss); |
528 |
|
|
acc -= htons(maxmss); |
529 |
|
|
ADJUST_CHECKSUM(acc, th->th_sum); |
530 |
|
|
} |
531 |
|
|
return 0; |
532 |
|
|
/* NOTREACHED */ |
533 |
|
|
break; |
534 |
|
|
case TCPOPT_EOL: |
535 |
|
|
return 0; |
536 |
|
|
/* NOTREACHED */ |
537 |
|
|
break; |
538 |
|
|
case TCPOPT_NOP: |
539 |
|
|
lpktp--; |
540 |
|
|
break; |
541 |
|
|
default: |
542 |
|
|
GETCHAR(optlen, pktp); |
543 |
|
|
if (optlen < 2) /* packet is broken */ |
544 |
|
|
return 1; |
545 |
|
|
pktp += optlen - 2; |
546 |
|
|
lpktp -= optlen; |
547 |
|
|
break; |
548 |
|
|
} |
549 |
|
|
} |
550 |
|
|
return 0; |
551 |
|
|
} |