New nd-proxy for RS/RA proxying
Signed-off-by: Blair Steven <blair.steven@alliedtelesis.co.nz>
This commit is contained in:
Carl Smith
Blair Steven
parent
cf244c10f7
commit
df16c053b0
8
Makefile
8
Makefile
@ -15,7 +15,7 @@ LIBS =
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OBJS = src/logger.o src/ndppd.o src/iface.o src/proxy.o src/address.o \
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OBJS = src/logger.o src/ndppd.o src/iface.o src/proxy.o src/address.o \
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src/rule.o src/session.o src/conf.o src/route.o
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src/rule.o src/session.o src/conf.o src/route.o
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all: ndppd ndppd.1.gz ndppd.conf.5.gz
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all: ndppd ndppd.1.gz ndppd.conf.5.gz nd-proxy
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install: all
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install: all
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mkdir -p ${SBINDIR} ${MANDIR} ${MANDIR}/man1 ${MANDIR}/man5
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mkdir -p ${SBINDIR} ${MANDIR} ${MANDIR}/man1 ${MANDIR}/man5
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@ -23,6 +23,7 @@ install: all
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chmod +x ${SBINDIR}/ndppd
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chmod +x ${SBINDIR}/ndppd
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cp ndppd.1.gz ${MANDIR}/man1
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cp ndppd.1.gz ${MANDIR}/man1
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cp ndppd.conf.5.gz ${MANDIR}/man5
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cp ndppd.conf.5.gz ${MANDIR}/man5
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cp nd-proxy ${SBINDIR}
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ndppd.1.gz:
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ndppd.1.gz:
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${GZIP} < ndppd.1 > ndppd.1.gz
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${GZIP} < ndppd.1 > ndppd.1.gz
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@ -33,8 +34,11 @@ ndppd.conf.5.gz:
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ndppd: ${OBJS}
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ndppd: ${OBJS}
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${CXX} -o ndppd ${LDFLAGS} ${LIBS} ${OBJS}
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${CXX} -o ndppd ${LDFLAGS} ${LIBS} ${OBJS}
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nd-proxy: nd-proxy.c
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${CXX} -o nd-proxy -Wall -Werror ${LDFLAGS} `pkg-config --cflags glib-2.0` nd-proxy.c `pkg-config --libs glib-2.0`
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.cc.o:
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.cc.o:
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${CXX} -c ${CPPFLAGS} $(CXXFLAGS) -o $@ $<
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${CXX} -c ${CPPFLAGS} $(CXXFLAGS) -o $@ $<
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clean:
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clean:
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rm -f ndppd ndppd.conf.5.gz ndppd.1.gz ${OBJS}
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rm -f ndppd ndppd.conf.5.gz ndppd.1.gz ${OBJS} nd-proxy
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550
nd-proxy.c
Normal file
550
nd-proxy.c
Normal file
@ -0,0 +1,550 @@
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/**
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* @file nd-proxy.c
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*
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* Copyright 2016, Allied Telesis Labs New Zealand, Ltd
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*
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* +---------+
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* If A | | If B
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* A-----------------| PROXY |-----------------B
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* | |
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* +---------+
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* IPv6: A IPv6: PA IPv6: PB IPv6: B
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* L2: a L2: pa L2: pb L2: b
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*
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* RS/RA proxy
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* RS
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* -------------------->
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* L3src=A, L3dst=AllR L3src=A, L3dst=AllR
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* L2src=a, L2dst=allr, SLL=a L2src=pb, L2dst=allr, SLL=pb
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*
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* RA
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* <--------------------
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* L3src=B, L3dst=AllN L3src=B, L3dst=AllN
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* L2src=pa, L2dst=alln, SLL=pa L2src=b, L2dst=alln, SLL=b
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <stdlib.h>
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#include <stdbool.h>
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#include <string.h>
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#include <stdio.h>
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#include <unistd.h>
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#include <syslog.h>
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#include <glib.h>
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#include <glib-unix.h>
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#include <netinet/in.h>
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#include <netinet/ip6.h>
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#include <netinet/icmp6.h>
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#include <netinet/ether.h>
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#include <netpacket/packet.h>
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#include <net/if.h>
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#include <sys/ioctl.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <sys/poll.h>
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#include <linux/filter.h>
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/* Mode */
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#define PROXY_RS (1 << 0)
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#define PROXY_RA (1 << 1)
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#define PROXY_NS (1 << 2)
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#define PROXY_NA (1 << 3)
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#define PROXY_RD (1 << 4)
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/* Debug macros */
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#define DEBUG(fmt, args...) if (debug) printf (fmt, ## args)
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#define ERROR(fmt, args...) \
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{ \
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syslog(LOG_ERR, fmt, ## args); \
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fprintf(stderr, fmt, ## args); \
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}
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/* Proxy interface */
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typedef struct _iface_t {
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char *name;
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uint32_t flags;
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int ifindex;
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uint8_t hwaddr[ETH_ALEN];
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int fd;
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guint src;
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} iface_t;
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/* Globals */
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static bool debug = false;
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static GList *ifaces = NULL;
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/* Find the specified option in the ICMPv6 message */
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static struct nd_opt_hdr *
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find_option(struct icmp6_hdr *icmp6_hdr, int len, uint8_t type)
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{
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struct nd_opt_hdr *nd_opt;
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int icmp_hlen;
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/* Each ND type has a different offest to the options */
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switch (icmp6_hdr->icmp6_type) {
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case ND_ROUTER_SOLICIT:
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icmp_hlen = sizeof(struct nd_router_solicit);
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break;
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case ND_ROUTER_ADVERT:
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icmp_hlen = sizeof(struct nd_router_advert);
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break;
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case ND_NEIGHBOR_SOLICIT:
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icmp_hlen = sizeof(struct nd_neighbor_solicit);
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break;
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case ND_NEIGHBOR_ADVERT:
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icmp_hlen = sizeof(struct nd_neighbor_advert);
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break;
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case ND_REDIRECT:
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icmp_hlen = sizeof(struct nd_redirect);
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break;
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default:
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return NULL;
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}
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/* Find the option */
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nd_opt = (struct nd_opt_hdr *)((uint8_t *)icmp6_hdr + icmp_hlen);
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len -= icmp_hlen;
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while (len > 0) {
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int opt_len = nd_opt->nd_opt_len * 8;
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if (nd_opt->nd_opt_type == type)
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return nd_opt;
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nd_opt = (struct nd_opt_hdr *)((uint8_t *)nd_opt +
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sizeof(struct nd_opt_hdr) + opt_len);
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len -= (sizeof(struct nd_opt_hdr) + opt_len);
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}
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return NULL;
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}
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/* Update the SLLA option in the packet (and checksum) */
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static void
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update_slla_option(struct icmp6_hdr *icmp6_hdr, int len, uint8_t *mac)
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{
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struct nd_opt_hdr *nd_opt;
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/* Find the "source link-layer address" option */
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nd_opt = find_option(icmp6_hdr, len, ND_OPT_SOURCE_LINKADDR);
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/* Update the slla if we found it */
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if (nd_opt) {
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/* Option data is the mac address - it is always 16-bit aligned */
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uint8_t *slla = (uint8_t *)nd_opt + sizeof(struct nd_opt_hdr);
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/* Update ICMPv6 header checksum based on the old and new mac adddress */
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uint16_t *omac = (uint16_t *)slla;
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uint16_t *nmac = (uint16_t *)mac;
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int i;
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for (i = 0; i < ETH_ALEN / 2; i++) {
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uint16_t hc_complement = ~ntohs(icmp6_hdr->icmp6_cksum);
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uint16_t m_complement = ~ntohs(omac[i]);
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uint16_t m_prime = ntohs(nmac[i]);
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uint32_t sum = hc_complement + m_complement + m_prime;
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while (sum >> 16) {
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sum = (sum & 0xffff) + (sum >> 16);
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}
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icmp6_hdr->icmp6_cksum = htons(~((uint16_t)sum));
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}
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/* Copy the outgoing interface's hw addr into the
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* "source link-layer address" option in the pkt. */
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memcpy(slla, mac, ETH_ALEN);
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}
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}
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/* Proxying of both RS and RA */
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static void
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proxy_rsra(iface_t *iface, uint8_t *msg, int len)
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{
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struct ether_header *eth_hdr;
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struct ip6_hdr *ip6;
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struct icmp6_hdr *icmp6_hdr;
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struct sockaddr_ll socket_address;
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/* Parse the packet */
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eth_hdr = (struct ether_header *)msg;
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ip6 = (struct ip6_hdr *)(msg + sizeof(struct ether_header));
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icmp6_hdr = (struct icmp6_hdr *)(msg + sizeof(struct ether_header) +
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sizeof(struct ip6_hdr));
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DEBUG("Tx(%s): %s\n", iface->name,
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icmp6_hdr->icmp6_type == ND_ROUTER_SOLICIT ?
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"ND_ROUTER_SOLICIT" : "ND_ROUTER_ADVERT");
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/* Avoid proxying spoofed packets */
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if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
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DEBUG("Tx(%s): Ignoring RS/RA from spoofed address\n", iface->name);
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return;
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}
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/* RS should be sent to "All Routers Address" FF02::2 */
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/* RA should be sent to "All Nodes Address" FF02::1 */
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/* Can only proxy to multicast L2 destinations 33:33:.. */
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if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
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(eth_hdr->ether_dhost[0] != 0x33 && eth_hdr->ether_dhost[1] != 0x33)) {
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DEBUG("Tx(%s): Ignoring RS/RA to non-multicast address\n", iface->name);
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return;
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}
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/* Copy the outgoing interface's hw addr into the
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* "source link-layer address" option in the pkt */
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update_slla_option(icmp6_hdr, len - ((uint8_t *)icmp6_hdr - msg), iface->hwaddr);
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/* Copy the outgoing interface's hw addr into the
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* MAC source address in the pkt. */
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memcpy((uint8_t *)(eth_hdr->ether_shost), iface->hwaddr, ETH_ALEN);
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/* Send the packet */
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socket_address.sll_ifindex = iface->ifindex;
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socket_address.sll_halen = ETH_ALEN;
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memcpy((uint8_t *)socket_address.sll_addr, iface->hwaddr, ETH_ALEN);
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if (sendto (iface->fd, msg, len, 0, (struct sockaddr *)&socket_address,
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sizeof(struct sockaddr_ll)) < 0) {
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ERROR("Tx(%s): Failed to send packet\n", iface->name);
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return;
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}
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}
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static gboolean
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handle_fd(gint fd, GIOCondition condition, gpointer data)
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{
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iface_t *iface = (iface_t *)data;
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struct msghdr mhdr;
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struct iovec iov;
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struct sockaddr_ll t_saddr;
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uint8_t msg[4096];
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int size = 4096;
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int len;
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/* Receive a packet */
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iov.iov_len = size;
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iov.iov_base = (caddr_t)msg;
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memset(&mhdr, 0, sizeof(mhdr));
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mhdr.msg_name = (caddr_t)&t_saddr;
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mhdr.msg_namelen = sizeof(struct sockaddr);
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mhdr.msg_iov = &iov;
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mhdr.msg_iovlen = 1;
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if ((len = recvmsg(fd, &mhdr, 0)) < 0) {
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ERROR("Rx(%s):Interface has gone away\n", iface->name);
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exit(-1);
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}
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/* Check we have at least the icmp header */
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if ((size_t) len < (ETH_HLEN + sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr))) {
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ERROR("Rx(%s): Ignoring short packet (%d bytes)\n", iface->name, len);
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return true;
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}
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struct icmp6_hdr *icmp6_hdr = (struct icmp6_hdr *)(msg + ETH_HLEN + sizeof(struct ip6_hdr));
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uint8_t icmp6_type = icmp6_hdr->icmp6_type;
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switch (icmp6_type) {
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case ND_ROUTER_SOLICIT:
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DEBUG("Rx(%s): ND_ROUTER_SOLICIT\n", iface->name);
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if (iface->flags & PROXY_RS) {
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GList *iter;
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for (iter = ifaces; iter; iter = g_list_next(iter)) {
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iface_t *oiface = (iface_t *)iter->data;
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if (oiface != iface)
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proxy_rsra(oiface, msg, len);
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}
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}
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break;
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case ND_ROUTER_ADVERT:
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DEBUG("Rx(%s): ND_ROUTER_ADVERT\n", iface->name);
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if (iface->flags & PROXY_RA) {
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GList *iter;
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for (iter = ifaces; iter; iter = g_list_next(iter)) {
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iface_t *oiface = (iface_t *)iter->data;
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if (oiface != iface)
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proxy_rsra(oiface, msg, len);
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}
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}
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break;
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case ND_NEIGHBOR_SOLICIT:
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case ND_NEIGHBOR_ADVERT:
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case ND_REDIRECT:
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default:
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DEBUG("Rx(%s): ignoring ICMPv6 packets of type %d\n", iface->name, icmp6_type);
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break;
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}
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return true;
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}
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static char *flags_to_string(uint32_t flags)
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{
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static char sbuffer[256];
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sbuffer[0] = '\0';
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if (flags == 0)
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sprintf(sbuffer, "no packets");
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if (flags & PROXY_NS)
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sprintf(sbuffer + strlen(sbuffer), "%sNS",
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strlen(sbuffer) ? "," : "");
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if (flags & PROXY_NA)
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sprintf(sbuffer + strlen(sbuffer), "%sNA",
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strlen(sbuffer) ? "," : "");
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if (flags & PROXY_RS)
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sprintf(sbuffer + strlen(sbuffer), "%sRS",
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strlen(sbuffer) ? "," : "");
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if (flags & PROXY_RA)
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sprintf(sbuffer + strlen(sbuffer), "%sRA",
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strlen(sbuffer) ? "," : "");
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if (flags & PROXY_RD)
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sprintf(sbuffer + strlen(sbuffer), "%sRD",
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strlen(sbuffer) ? "," : "");
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return sbuffer;
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}
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static struct sock_filter bpf_filter[] = {
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||||||
|
/* Load the ether_type. */
|
||||||
|
BPF_STMT(BPF_LD | BPF_H | BPF_ABS,
|
||||||
|
offsetof(struct ether_header, ether_type)),
|
||||||
|
/* Bail if it's* not* ETHERTYPE_IPV6. */
|
||||||
|
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, ETHERTYPE_IPV6, 0, 9),
|
||||||
|
/* Load the next header type. */
|
||||||
|
BPF_STMT(BPF_LD | BPF_B | BPF_ABS,
|
||||||
|
sizeof(struct ether_header) + offsetof(struct ip6_hdr,
|
||||||
|
ip6_nxt)),
|
||||||
|
/* Bail if it's* not* IPPROTO_ICMPV6. */
|
||||||
|
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, IPPROTO_ICMPV6, 0, 7),
|
||||||
|
/* Load the ICMPv6 type. */
|
||||||
|
BPF_STMT(BPF_LD | BPF_B | BPF_ABS,
|
||||||
|
sizeof(struct ether_header) + sizeof(struct ip6_hdr) +
|
||||||
|
offsetof(struct icmp6_hdr, icmp6_type)),
|
||||||
|
/* Bail if it's* not* ND */
|
||||||
|
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, ND_ROUTER_SOLICIT, 4, 0),
|
||||||
|
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, ND_ROUTER_ADVERT, 3, 0),
|
||||||
|
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, ND_NEIGHBOR_SOLICIT, 2, 0),
|
||||||
|
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, ND_NEIGHBOR_ADVERT, 1, 0),
|
||||||
|
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, ND_REDIRECT, 0, 1),
|
||||||
|
/* Keep packet. */
|
||||||
|
BPF_STMT(BPF_RET | BPF_K, (u_int32_t)-1),
|
||||||
|
/* Drop packet. */
|
||||||
|
BPF_STMT(BPF_RET | BPF_K, 0)
|
||||||
|
};
|
||||||
|
|
||||||
|
static void iface_open(gpointer data, gpointer user)
|
||||||
|
{
|
||||||
|
iface_t *iface = (iface_t *)data;
|
||||||
|
struct sockaddr_ll lladdr;
|
||||||
|
struct sock_fprog fprog;
|
||||||
|
struct ifreq ifr;
|
||||||
|
int on = 1;
|
||||||
|
int fd;
|
||||||
|
|
||||||
|
DEBUG("Open(%s): %s\n", iface->name, flags_to_string(iface->flags));
|
||||||
|
|
||||||
|
/* Check the interface exists by getting its ifindex */
|
||||||
|
iface->ifindex = if_nametoindex(iface->name);
|
||||||
|
if (!iface->ifindex) {
|
||||||
|
ERROR("Open(%s): Could not find interface\n", iface->name);
|
||||||
|
exit(-1);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Create raw socket for tx/rx of IPv6 packets */
|
||||||
|
if ((fd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_IPV6))) < 0) {
|
||||||
|
ERROR("Open(%s): Unable to create socket\n", iface->name);
|
||||||
|
exit(-1);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Bind the socket to the specified interface */
|
||||||
|
memset(&lladdr, 0, sizeof(struct sockaddr_ll));
|
||||||
|
lladdr.sll_family = AF_PACKET;
|
||||||
|
lladdr.sll_protocol = htons(ETH_P_IPV6);
|
||||||
|
lladdr.sll_ifindex = iface->ifindex;
|
||||||
|
if (bind(fd, (struct sockaddr *)&lladdr, sizeof(struct sockaddr_ll)) < 0) {
|
||||||
|
close(fd);
|
||||||
|
ERROR("Open(%s): Failed to bind to interface\n", iface->name);
|
||||||
|
exit(-1);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Set the socket non-blocking */
|
||||||
|
if (ioctl(fd, FIONBIO, (char *)&on) < 0) {
|
||||||
|
close(fd);
|
||||||
|
ERROR("Open(%s): Failed to make interface non-blocking\n", iface->name);
|
||||||
|
exit(-1);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Setup a filter to only receive ND packets */
|
||||||
|
fprog.len = sizeof(bpf_filter) / sizeof(bpf_filter[0]);
|
||||||
|
fprog.filter = bpf_filter;
|
||||||
|
if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &fprog, sizeof(fprog)) < 0) {
|
||||||
|
close(fd);
|
||||||
|
ERROR("Open(%s): Failed to set filter for ND packets\n", iface->name);
|
||||||
|
exit(-1);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Enable all multicast for this interface */
|
||||||
|
memset(&ifr, 0, sizeof(struct ifreq));
|
||||||
|
strncpy(ifr.ifr_name, iface->name, IFNAMSIZ - 1);
|
||||||
|
if (ioctl(fd, SIOCGIFFLAGS, &ifr) < 0) {
|
||||||
|
close(fd);
|
||||||
|
ERROR("Open(%s): Failed to get flags for interface\n", iface->name);
|
||||||
|
exit(-1);
|
||||||
|
}
|
||||||
|
ifr.ifr_flags |= IFF_ALLMULTI;
|
||||||
|
if (ioctl(fd, SIOCSIFFLAGS, &ifr) < 0) {
|
||||||
|
close(fd);
|
||||||
|
ERROR("Open(%s): Failed to set flags for interface\n", iface->name);
|
||||||
|
exit(-1);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Get the hwaddr of the interface */
|
||||||
|
memset(&ifr, 0, sizeof(struct ifreq));
|
||||||
|
strncpy(ifr.ifr_name, iface->name, IFNAMSIZ - 1);
|
||||||
|
if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
|
||||||
|
ERROR("Open(%s): Failed to get interface hwaddr\n", iface->name);
|
||||||
|
exit(-1);
|
||||||
|
}
|
||||||
|
memcpy(iface->hwaddr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
|
||||||
|
|
||||||
|
/* Watch for packets */
|
||||||
|
iface->fd = fd;
|
||||||
|
iface->src = g_unix_fd_add(fd, G_IO_IN, handle_fd, iface);
|
||||||
|
}
|
||||||
|
|
||||||
|
static void iface_close(gpointer data)
|
||||||
|
{
|
||||||
|
iface_t *iface = (iface_t *)data;
|
||||||
|
DEBUG("Close(%s)\n", iface->name);
|
||||||
|
g_source_remove(iface->src);
|
||||||
|
close(iface->fd);
|
||||||
|
free(iface->name);
|
||||||
|
free(iface);
|
||||||
|
}
|
||||||
|
|
||||||
|
static iface_t *parse_interface(char *desc)
|
||||||
|
{
|
||||||
|
char *name = NULL;
|
||||||
|
uint32_t flags = PROXY_RS | PROXY_RA;
|
||||||
|
char *pflags = strchr(desc, ':');
|
||||||
|
|
||||||
|
if (pflags) {
|
||||||
|
char *token = strtok(pflags + 1, ",");
|
||||||
|
flags = 0;
|
||||||
|
while (token != NULL) {
|
||||||
|
if (strcmp("NS", token) == 0)
|
||||||
|
flags |= PROXY_NS;
|
||||||
|
else if (strcmp("NA", token) == 0)
|
||||||
|
flags |= PROXY_NA;
|
||||||
|
else if (strcmp("RA", token) == 0)
|
||||||
|
flags |= PROXY_RA;
|
||||||
|
else if (strcmp("RS", token) == 0)
|
||||||
|
flags |= PROXY_RS;
|
||||||
|
else if (strcmp("RD", token) == 0)
|
||||||
|
flags |= PROXY_RD;
|
||||||
|
else
|
||||||
|
return NULL;
|
||||||
|
token = strtok(NULL, ",");
|
||||||
|
}
|
||||||
|
name = strndup(desc, pflags - desc);
|
||||||
|
} else {
|
||||||
|
name = strdup(desc);
|
||||||
|
}
|
||||||
|
iface_t *iface = (iface_t *)g_malloc0(sizeof(iface_t));
|
||||||
|
iface->name = name;
|
||||||
|
iface->flags = flags;
|
||||||
|
iface->fd = -1;
|
||||||
|
iface->src = 0;
|
||||||
|
return iface;
|
||||||
|
}
|
||||||
|
|
||||||
|
static gboolean termination_handler(gpointer arg1)
|
||||||
|
{
|
||||||
|
GMainLoop *loop = (GMainLoop *) arg1;
|
||||||
|
g_main_loop_quit(loop);
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
|
||||||
|
void help(char *app_name)
|
||||||
|
{
|
||||||
|
printf("Usage: %s [-h] [-b] [-d] -i <interface>[:<type>[,<type>]..]\n"
|
||||||
|
" -h show this help\n"
|
||||||
|
" -b background mode\n"
|
||||||
|
" -d enable verbose debug\n"
|
||||||
|
" -i proxy [NS,NA,RS,RA,RD] messages received on <interface>\n"
|
||||||
|
"\n" "e.g %s -i eth1:RS -i eth2:RA\n", app_name, app_name);
|
||||||
|
}
|
||||||
|
|
||||||
|
int main(int argc, char *argv[])
|
||||||
|
{
|
||||||
|
int i = 0;
|
||||||
|
bool background = false;
|
||||||
|
GMainLoop *loop = NULL;
|
||||||
|
|
||||||
|
/* Parse options */
|
||||||
|
while ((i = getopt(argc, argv, "hdbi:")) != -1) {
|
||||||
|
switch (i) {
|
||||||
|
case 'd':
|
||||||
|
debug = true;
|
||||||
|
background = false;
|
||||||
|
break;
|
||||||
|
case 'b':
|
||||||
|
background = true;
|
||||||
|
break;
|
||||||
|
case 'i':
|
||||||
|
{
|
||||||
|
iface_t *iface = parse_interface(optarg);
|
||||||
|
if (!iface) {
|
||||||
|
help(argv[0]);
|
||||||
|
ERROR("ERROR: Invalid interface specification (%s)\n", optarg);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
ifaces = g_list_prepend(ifaces, iface);
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
case '?':
|
||||||
|
case 'h':
|
||||||
|
default:
|
||||||
|
help(argv[0]);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Check required */
|
||||||
|
if (g_list_length(ifaces) < 2) {
|
||||||
|
help(argv[0]);
|
||||||
|
ERROR("ERROR: Require at least 2 interfaces.\n");
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Daemonize */
|
||||||
|
if (background && fork() != 0) {
|
||||||
|
/* Parent */
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Main loop instance */
|
||||||
|
loop = g_main_loop_new(NULL, true);
|
||||||
|
|
||||||
|
/* Handle SIGTERM/SIGINT/SIGPIPE gracefully */
|
||||||
|
g_unix_signal_add(SIGINT, termination_handler, loop);
|
||||||
|
g_unix_signal_add(SIGTERM, termination_handler, loop);
|
||||||
|
|
||||||
|
/* Startup */
|
||||||
|
g_list_foreach(ifaces, iface_open, NULL);
|
||||||
|
|
||||||
|
/* Loop while not terminated */
|
||||||
|
g_main_loop_run(loop);
|
||||||
|
|
||||||
|
/* Shutdown */
|
||||||
|
g_list_free_full(ifaces, iface_close);
|
||||||
|
|
||||||
|
/* Free the glib main loop */
|
||||||
|
if (loop)
|
||||||
|
g_main_loop_unref(loop);
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
Loading…
x
Reference in New Issue
Block a user