Copy structs from packets to the stack before using them, to prevent
alignment issues.
This commit is contained in:
Guus Sliepen
parent
acbb9d6692
commit
60943122f7
1 changed files with 174 additions and 133 deletions
307
src/route.c
307
src/route.c
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@ -17,7 +17,7 @@
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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$Id: route.c,v 1.1.2.66 2003/10/01 09:14:01 guus Exp $
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$Id: route.c,v 1.1.2.67 2003/10/06 13:49:57 guus Exp $
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*/
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#include "system.h"
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@ -57,6 +57,17 @@ int macexpire = 600;
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bool overwrite_mac = false;
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mac_t mymac = {{0xFE, 0xFD, 0, 0, 0, 0}};
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/* Sizes of various headers */
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static size_t ether_size = sizeof(struct ether_header);
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static size_t arp_size = sizeof(struct ether_arp);
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static size_t ip_size = sizeof(struct ip);
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static size_t icmp_size = sizeof(struct icmp) - sizeof(struct ip);
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static size_t ip6_size = sizeof(struct ip6_hdr);
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static size_t icmp6_size = sizeof(struct icmp6_hdr);
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static size_t ns_size = sizeof(struct nd_neighbor_solicit);
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static size_t opt_size = sizeof(struct nd_opt_hdr);
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/* RFC 1071 */
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static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
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@ -78,13 +89,18 @@ static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
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return ~checksum;
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}
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static bool ratelimit(void) {
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static bool ratelimit(int frequency) {
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static time_t lasttime = 0;
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static int count = 0;
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if(lasttime == now)
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return true;
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if(lasttime == now) {
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if(++count > frequency)
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return true;
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} else {
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lasttime = now;
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count = 0;
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}
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lasttime = now;
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return false;
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}
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@ -174,59 +190,68 @@ static node_t *route_mac(vpn_packet_t *packet)
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static void route_ipv4_unreachable(vpn_packet_t *packet, uint8_t code)
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{
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struct ip *hdr;
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struct icmp *icmp;
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struct ip ip;
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struct icmp icmp;
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struct in_addr ip_src;
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struct in_addr ip_dst;
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uint32_t oldlen;
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if(ratelimit())
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if(ratelimit(3))
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return;
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cp();
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hdr = (struct ip *)(packet->data + 14);
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icmp = (struct icmp *)(packet->data + 14 + 20);
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/* Copy headers from packet into properly aligned structs on the stack */
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memcpy(&ip, packet->data + ether_size, ip_size);
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memcpy(&icmp, packet->data + ether_size + ip_size, icmp_size);
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/* Remember original source and destination */
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memcpy(&ip_src, &hdr->ip_src, 4);
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memcpy(&ip_dst, &hdr->ip_dst, 4);
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oldlen = packet->len - 14;
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memcpy(&ip_src, &ip.ip_src, sizeof(ip_src));
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memcpy(&ip_dst, &ip.ip_dst, sizeof(ip_dst));
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oldlen = packet->len - ether_size;
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if(oldlen >= IP_MSS - sizeof(*hdr) - sizeof(*icmp))
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oldlen = IP_MSS - sizeof(*hdr) - sizeof(*icmp);
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if(oldlen >= IP_MSS - ip_size - icmp_size)
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oldlen = IP_MSS - ip_size - icmp_size;
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/* Copy first part of original contents to ICMP message */
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memmove(&icmp->icmp_ip, hdr, oldlen);
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memmove(packet->data + ether_size + ip_size + icmp_size, packet->data + ether_size, oldlen);
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/* Fill in IPv4 header */
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hdr->ip_v = 4;
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hdr->ip_hl = sizeof(*hdr) / 4;
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hdr->ip_tos = 0;
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hdr->ip_len = htons(20 + 8 + oldlen);
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hdr->ip_id = 0;
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hdr->ip_off = 0;
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hdr->ip_ttl = 255;
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hdr->ip_p = IPPROTO_ICMP;
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hdr->ip_sum = 0;
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memcpy(&hdr->ip_src, &ip_dst, 4);
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memcpy(&hdr->ip_dst, &ip_src, 4);
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ip.ip_v = 4;
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ip.ip_hl = ip_size / 4;
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ip.ip_tos = 0;
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ip.ip_len = htons(ip_size + icmp_size + oldlen);
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ip.ip_id = 0;
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ip.ip_off = 0;
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ip.ip_ttl = 255;
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ip.ip_p = IPPROTO_ICMP;
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ip.ip_sum = 0;
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memcpy(&ip.ip_src, &ip_dst, sizeof(ip_src));
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memcpy(&ip.ip_dst, &ip_src, sizeof(ip_dst));
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hdr->ip_sum = inet_checksum(hdr, 20, ~0);
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ip.ip_sum = inet_checksum(&ip, ip_size, ~0);
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/* Fill in ICMP header */
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icmp->icmp_type = ICMP_DEST_UNREACH;
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icmp->icmp_code = code;
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icmp->icmp_cksum = 0;
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icmp.icmp_type = ICMP_DEST_UNREACH;
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icmp.icmp_code = code;
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icmp.icmp_cksum = 0;
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icmp->icmp_cksum = inet_checksum(icmp, 8 + oldlen, ~0);
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icmp.icmp_cksum = inet_checksum(&icmp, icmp_size, ~0);
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icmp.icmp_cksum = inet_checksum(packet->data + ether_size + ip_size + icmp_size, oldlen, icmp.icmp_cksum);
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/* Copy structs on stack back to packet */
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memcpy(packet->data + ether_size, &ip, ip_size);
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memcpy(packet->data + ether_size + ip_size, &icmp, icmp_size);
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packet->len = 14 + 20 + 8 + oldlen;
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packet->len = ether_size + ip_size + icmp_size + oldlen;
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write_packet(packet);
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}
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@ -261,8 +286,8 @@ static node_t *route_ipv4(vpn_packet_t *packet)
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static void route_ipv6_unreachable(vpn_packet_t *packet, uint8_t code)
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{
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struct ip6_hdr *hdr;
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struct icmp6_hdr *icmp;
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struct ip6_hdr ip6;
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struct icmp6_hdr icmp6;
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uint16_t checksum;
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struct {
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@ -272,55 +297,64 @@ static void route_ipv6_unreachable(vpn_packet_t *packet, uint8_t code)
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uint32_t next;
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} pseudo;
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if(ratelimit())
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if(ratelimit(3))
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return;
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cp();
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hdr = (struct ip6_hdr *)(packet->data + 14);
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icmp = (struct icmp6_hdr *)(packet->data + 14 + sizeof(*hdr));
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/* Copy headers from packet to structs on the stack */
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memcpy(&ip6, packet->data + ether_size, ip6_size);
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memcpy(&icmp6, packet->data + ether_size + ip6_size, icmp6_size);
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/* Remember original source and destination */
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memcpy(&pseudo.ip6_src, &hdr->ip6_dst, 16);
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memcpy(&pseudo.ip6_dst, &hdr->ip6_src, 16);
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pseudo.length = ntohs(hdr->ip6_plen) + sizeof(*hdr);
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memcpy(&pseudo.ip6_src, &ip6.ip6_dst, sizeof(ip6.ip6_src));
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memcpy(&pseudo.ip6_dst, &ip6.ip6_src, sizeof(ip6.ip6_dst));
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pseudo.length = ntohs(ip6.ip6_plen) + ip6_size;
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if(pseudo.length >= IP_MSS - sizeof(*hdr) - sizeof(*icmp))
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pseudo.length = IP_MSS - sizeof(*hdr) - sizeof(*icmp);
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if(pseudo.length >= IP_MSS - ip6_size - icmp6_size)
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pseudo.length = IP_MSS - ip6_size - icmp6_size;
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/* Copy first part of original contents to ICMP message */
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memmove(((char *)icmp) + sizeof(*icmp), hdr, pseudo.length);
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memmove(packet->data + ether_size + ip6_size + icmp6_size, packet->data + ether_size, pseudo.length);
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/* Fill in IPv6 header */
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hdr->ip6_flow = htonl(0x60000000UL);
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hdr->ip6_plen = htons(sizeof(*icmp) + pseudo.length);
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hdr->ip6_nxt = IPPROTO_ICMPV6;
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hdr->ip6_hlim = 255;
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memcpy(&hdr->ip6_dst, &pseudo.ip6_dst, 16);
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memcpy(&hdr->ip6_src, &pseudo.ip6_src, 16);
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ip6.ip6_flow = htonl(0x60000000UL);
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ip6.ip6_plen = htons(icmp6_size + pseudo.length);
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ip6.ip6_nxt = IPPROTO_ICMPV6;
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ip6.ip6_hlim = 255;
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memcpy(&ip6.ip6_src, &pseudo.ip6_src, sizeof(ip6.ip6_src));
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memcpy(&ip6.ip6_dst, &pseudo.ip6_dst, sizeof(ip6.ip6_dst));
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/* Fill in ICMP header */
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icmp->icmp6_type = ICMP6_DST_UNREACH;
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icmp->icmp6_code = code;
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icmp->icmp6_cksum = 0;
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icmp6.icmp6_type = ICMP6_DST_UNREACH;
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icmp6.icmp6_code = code;
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icmp6.icmp6_cksum = 0;
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/* Create pseudo header */
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pseudo.length = htonl(sizeof(*icmp) + pseudo.length);
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pseudo.length = htonl(icmp6_size + pseudo.length);
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pseudo.next = htonl(IPPROTO_ICMPV6);
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/* Generate checksum */
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checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
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checksum = inet_checksum(icmp, ntohl(pseudo.length), checksum);
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checksum = inet_checksum(&icmp6, icmp6_size, checksum);
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checksum = inet_checksum(packet->data + ether_size + ip6_size + icmp6_size, ntohl(pseudo.length) - icmp6_size, checksum);
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icmp->icmp6_cksum = checksum;
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icmp6.icmp6_cksum = checksum;
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/* Copy structs on stack back to packet */
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memcpy(packet->data + ether_size, &ip6, ip6_size);
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memcpy(packet->data + ether_size + ip6_size, &icmp6, icmp6_size);
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packet->len = 14 + sizeof(*hdr) + ntohl(pseudo.length);
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packet->len = ether_size + ip6_size + ntohl(pseudo.length);
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write_packet(packet);
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}
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@ -358,9 +392,9 @@ static node_t *route_ipv6(vpn_packet_t *packet)
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static void route_neighborsol(vpn_packet_t *packet)
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{
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struct ip6_hdr *hdr;
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struct nd_neighbor_solicit *ns;
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struct nd_opt_hdr *opt;
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struct ip6_hdr ip6;
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struct nd_neighbor_solicit ns;
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struct nd_opt_hdr opt;
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subnet_t *subnet;
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uint16_t checksum;
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@ -373,34 +407,37 @@ static void route_neighborsol(vpn_packet_t *packet)
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cp();
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hdr = (struct ip6_hdr *)(packet->data + 14);
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ns = (struct nd_neighbor_solicit *)(packet->data + 14 + sizeof(*hdr));
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opt = (struct nd_opt_hdr *)(packet->data + 14 + sizeof(*hdr) + sizeof(*ns));
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/* Copy headers from packet to structs on the stack */
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memcpy(&ip6, packet->data + ether_size, ip6_size);
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memcpy(&ns, packet->data + ether_size + ip6_size, ns_size);
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memcpy(&opt, packet->data + ether_size + ip6_size + ns_size, opt_size);
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/* First, snatch the source address from the neighbor solicitation packet */
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if(overwrite_mac)
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memcpy(mymac.x, packet->data + 6, 6);
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memcpy(mymac.x, packet->data + ETH_ALEN, ETH_ALEN);
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/* Check if this is a valid neighbor solicitation request */
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if(ns->nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT ||
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opt->nd_opt_type != ND_OPT_SOURCE_LINKADDR) {
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if(ns.nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT ||
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opt.nd_opt_type != ND_OPT_SOURCE_LINKADDR) {
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ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: received unknown type neighbor solicitation request"));
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return;
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}
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/* Create pseudo header */
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memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
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memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
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pseudo.length = htonl(sizeof(*ns) + sizeof(*opt) + 6);
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memcpy(&pseudo.ip6_src, &ip6.ip6_src, sizeof(ip6.ip6_src));
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memcpy(&pseudo.ip6_dst, &ip6.ip6_dst, sizeof(ip6.ip6_dst));
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pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
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pseudo.next = htonl(IPPROTO_ICMPV6);
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/* Generate checksum */
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checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
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checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
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checksum = inet_checksum(&ns, ns_size, checksum);
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checksum = inet_checksum(&opt, opt_size, checksum);
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if(checksum) {
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ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: checksum error for neighbor solicitation request"));
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@ -409,18 +446,18 @@ static void route_neighborsol(vpn_packet_t *packet)
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/* Check if the IPv6 address exists on the VPN */
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subnet = lookup_subnet_ipv6((ipv6_t *) &ns->nd_ns_target);
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subnet = lookup_subnet_ipv6((ipv6_t *) &ns.nd_ns_target);
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if(!subnet) {
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ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: neighbor solicitation request for unknown address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"),
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ntohs(((uint16_t *) &ns->nd_ns_target)[0]),
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ntohs(((uint16_t *) &ns->nd_ns_target)[1]),
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ntohs(((uint16_t *) &ns->nd_ns_target)[2]),
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ntohs(((uint16_t *) &ns->nd_ns_target)[3]),
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ntohs(((uint16_t *) &ns->nd_ns_target)[4]),
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ntohs(((uint16_t *) &ns->nd_ns_target)[5]),
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ntohs(((uint16_t *) &ns->nd_ns_target)[6]),
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ntohs(((uint16_t *) &ns->nd_ns_target)[7]));
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ntohs(((uint16_t *) &ns.nd_ns_target)[0]),
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ntohs(((uint16_t *) &ns.nd_ns_target)[1]),
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ntohs(((uint16_t *) &ns.nd_ns_target)[2]),
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ntohs(((uint16_t *) &ns.nd_ns_target)[3]),
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ntohs(((uint16_t *) &ns.nd_ns_target)[4]),
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ntohs(((uint16_t *) &ns.nd_ns_target)[5]),
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ntohs(((uint16_t *) &ns.nd_ns_target)[6]),
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ntohs(((uint16_t *) &ns.nd_ns_target)[7]));
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return;
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}
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@ -432,35 +469,39 @@ static void route_neighborsol(vpn_packet_t *packet)
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/* Create neighbor advertation reply */
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memcpy(packet->data, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* copy destination address */
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packet->data[ETHER_ADDR_LEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
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memcpy(packet->data, packet->data + ETH_ALEN, ETH_ALEN); /* copy destination address */
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packet->data[ETH_ALEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
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memcpy(&hdr->ip6_dst, &hdr->ip6_src, 16); /* swap destination and source protocol address */
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memcpy(&hdr->ip6_src, &ns->nd_ns_target, 16); /* ... */
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memcpy(&ip6.ip6_src, &ns.nd_ns_target, sizeof(ip6.ip6_src)); /* swap destination and source protocol address */
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memcpy(&ip6.ip6_dst, &ip6.ip6_src, sizeof(ip6.ip6_dst)); /* ... */
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memcpy((char *) opt + sizeof(*opt), packet->data + ETHER_ADDR_LEN, 6); /* add fake source hard addr */
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memcpy(&opt + opt_size, packet->data + ETH_ALEN, ETH_ALEN); /* add fake source hard addr */
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ns->nd_ns_hdr.icmp6_cksum = 0;
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ns->nd_ns_hdr.icmp6_type = ND_NEIGHBOR_ADVERT;
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ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[0] = 0x40; /* Set solicited flag */
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ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[1] =
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ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[2] =
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ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[3] = 0;
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opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
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ns.nd_ns_cksum = 0;
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ns.nd_ns_type = ND_NEIGHBOR_ADVERT;
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ns.nd_ns_reserved = htonl(0x40000000UL); /* Set solicited flag */
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opt.nd_opt_type = ND_OPT_TARGET_LINKADDR;
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/* Create pseudo header */
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memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
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memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
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pseudo.length = htonl(sizeof(*ns) + sizeof(*opt) + 6);
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memcpy(&pseudo.ip6_src, &ip6.ip6_src, sizeof(ip6.ip6_src));
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memcpy(&pseudo.ip6_dst, &ip6.ip6_dst, sizeof(ip6.ip6_dst));
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pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
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pseudo.next = htonl(IPPROTO_ICMPV6);
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/* Generate checksum */
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checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
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checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
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checksum = inet_checksum(&ns, ns_size, checksum);
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checksum = inet_checksum(&opt, opt_size, checksum);
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ns->nd_ns_hdr.icmp6_cksum = checksum;
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ns.nd_ns_hdr.icmp6_cksum = checksum;
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|
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/* Copy structs on stack back to packet */
|
||||
|
||||
memcpy(packet->data + ether_size, &ip6, ip6_size);
|
||||
memcpy(packet->data + ether_size + ip6_size, &ns, ns_size);
|
||||
memcpy(packet->data + ether_size + ip6_size + ns_size, &opt, opt_size);
|
||||
|
||||
write_packet(packet);
|
||||
}
|
||||
|
|
@ -469,40 +510,37 @@ static void route_neighborsol(vpn_packet_t *packet)
|
|||
|
||||
static void route_arp(vpn_packet_t *packet)
|
||||
{
|
||||
struct ether_arp *arp;
|
||||
struct ether_arp arp;
|
||||
subnet_t *subnet;
|
||||
uint8_t ipbuf[4];
|
||||
struct in_addr addr;
|
||||
|
||||
cp();
|
||||
|
||||
/* First, snatch the source address from the ARP packet */
|
||||
|
||||
if(overwrite_mac)
|
||||
memcpy(mymac.x, packet->data + 6, 6);
|
||||
memcpy(mymac.x, packet->data + ETH_ALEN, ETH_ALEN);
|
||||
|
||||
/* This routine generates replies to ARP requests.
|
||||
You don't need to set NOARP flag on the interface anymore (which is broken on FreeBSD).
|
||||
Most of the code here is taken from choparp.c by Takamichi Tateoka (tree@mma.club.uec.ac.jp)
|
||||
*/
|
||||
/* Copy headers from packet to structs on the stack */
|
||||
|
||||
arp = (struct ether_arp *)(packet->data + 14);
|
||||
memcpy(&arp, packet->data + ether_size, arp_size);
|
||||
|
||||
/* Check if this is a valid ARP request */
|
||||
|
||||
if(ntohs(arp->arp_hrd) != ARPHRD_ETHER || ntohs(arp->arp_pro) != ETHERTYPE_IP ||
|
||||
arp->arp_hln != ETHER_ADDR_LEN || arp->arp_pln != 4 || ntohs(arp->arp_op) != ARPOP_REQUEST) {
|
||||
if(ntohs(arp.arp_hrd) != ARPHRD_ETHER || ntohs(arp.arp_pro) != ETH_P_IP ||
|
||||
arp.arp_hln != ETH_ALEN || arp.arp_pln != sizeof(addr) || ntohs(arp.arp_op) != ARPOP_REQUEST) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: received unknown type ARP request"));
|
||||
return;
|
||||
}
|
||||
|
||||
/* Check if the IPv4 address exists on the VPN */
|
||||
|
||||
subnet = lookup_subnet_ipv4((ipv4_t *) arp->arp_tpa);
|
||||
subnet = lookup_subnet_ipv4((ipv4_t *) &arp.arp_tpa);
|
||||
|
||||
if(!subnet) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: ARP request for unknown address %d.%d.%d.%d"),
|
||||
arp->arp_tpa[0], arp->arp_tpa[1], arp->arp_tpa[2],
|
||||
arp->arp_tpa[3]);
|
||||
arp.arp_tpa[0], arp.arp_tpa[1], arp.arp_tpa[2],
|
||||
arp.arp_tpa[3]);
|
||||
return;
|
||||
}
|
||||
|
||||
|
|
@ -511,16 +549,20 @@ static void route_arp(vpn_packet_t *packet)
|
|||
if(subnet->owner == myself)
|
||||
return; /* silently ignore */
|
||||
|
||||
memcpy(packet->data, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* copy destination address */
|
||||
packet->data[ETHER_ADDR_LEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
|
||||
memcpy(packet->data, packet->data + ETH_ALEN, ETH_ALEN); /* copy destination address */
|
||||
packet->data[ETH_ALEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
|
||||
|
||||
memcpy(ipbuf, arp->arp_tpa, 4); /* save protocol addr */
|
||||
memcpy(arp->arp_tpa, arp->arp_spa, 4); /* swap destination and source protocol address */
|
||||
memcpy(arp->arp_spa, ipbuf, 4); /* ... */
|
||||
memcpy(&addr, arp.arp_tpa, sizeof(addr)); /* save protocol addr */
|
||||
memcpy(arp.arp_tpa, arp.arp_spa, sizeof(addr)); /* swap destination and source protocol address */
|
||||
memcpy(arp.arp_spa, &addr, sizeof(addr)); /* ... */
|
||||
|
||||
memcpy(arp->arp_tha, arp->arp_sha, 10); /* set target hard/proto addr */
|
||||
memcpy(arp->arp_sha, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* add fake source hard addr */
|
||||
arp->arp_op = htons(ARPOP_REPLY);
|
||||
memcpy(arp.arp_tha, arp.arp_sha, ETH_ALEN); /* set target hard/proto addr */
|
||||
memcpy(arp.arp_sha, packet->data + ETH_ALEN, ETH_ALEN); /* add fake source hard addr */
|
||||
arp.arp_op = htons(ARPOP_REPLY);
|
||||
|
||||
/* Copy structs on stack back to packet */
|
||||
|
||||
memcpy(packet->data + ether_size, &arp, arp_size);
|
||||
|
||||
write_packet(packet);
|
||||
}
|
||||
|
|
@ -532,7 +574,7 @@ void route_outgoing(vpn_packet_t *packet)
|
|||
|
||||
cp();
|
||||
|
||||
if(packet->len < 14) {
|
||||
if(packet->len < ether_size) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
|
||||
return;
|
||||
}
|
||||
|
|
@ -543,8 +585,8 @@ void route_outgoing(vpn_packet_t *packet)
|
|||
case RMODE_ROUTER:
|
||||
type = ntohs(*((uint16_t *)(&packet->data[12])));
|
||||
switch (type) {
|
||||
case 0x0800:
|
||||
if(packet->len < 34) {
|
||||
case ETH_P_IP:
|
||||
if(packet->len < ether_size + ip_size) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
|
||||
return;
|
||||
}
|
||||
|
|
@ -552,21 +594,21 @@ void route_outgoing(vpn_packet_t *packet)
|
|||
n = route_ipv4(packet);
|
||||
break;
|
||||
|
||||
case 0x86DD:
|
||||
if(packet->len < 54) {
|
||||
case ETH_P_IPV6:
|
||||
if(packet->len < ether_size + ip6_size) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
|
||||
return;
|
||||
}
|
||||
|
||||
if(packet->data[20] == IPPROTO_ICMPV6 && packet->len >= 62 && packet->data[54] == ND_NEIGHBOR_SOLICIT) {
|
||||
if(packet->data[20] == IPPROTO_ICMPV6 && packet->len >= ether_size + ip6_size + ns_size && packet->data[54] == ND_NEIGHBOR_SOLICIT) {
|
||||
route_neighborsol(packet);
|
||||
return;
|
||||
}
|
||||
n = route_ipv6(packet);
|
||||
break;
|
||||
|
||||
case 0x0806:
|
||||
if(packet->len < 42) {
|
||||
case ETH_P_ARP:
|
||||
if(packet->len < ether_size + arp_size) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
|
||||
return;
|
||||
}
|
||||
|
|
@ -598,9 +640,8 @@ void route_outgoing(vpn_packet_t *packet)
|
|||
|
||||
void route_incoming(node_t *source, vpn_packet_t *packet)
|
||||
{
|
||||
if(packet->len < 14) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Got too short packet from %s (%s)"),
|
||||
source->name, source->hostname);
|
||||
if(packet->len < ether_size) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
|
||||
return;
|
||||
}
|
||||
|
||||
|
|
@ -612,8 +653,8 @@ void route_incoming(node_t *source, vpn_packet_t *packet)
|
|||
|
||||
type = ntohs(*((uint16_t *)(&packet->data[12])));
|
||||
switch (type) {
|
||||
case 0x0800:
|
||||
if(packet->len < 34) {
|
||||
case ETH_P_IP:
|
||||
if(packet->len < ether_size + ip_size) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
|
||||
return;
|
||||
}
|
||||
|
|
@ -621,8 +662,8 @@ void route_incoming(node_t *source, vpn_packet_t *packet)
|
|||
n = route_ipv4(packet);
|
||||
break;
|
||||
|
||||
case 0x86DD:
|
||||
if(packet->len < 54) {
|
||||
case ETH_P_IPV6:
|
||||
if(packet->len < ether_size + ip6_size) {
|
||||
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
|
||||
return;
|
||||
}
|
||||
|
|
@ -638,7 +679,7 @@ void route_incoming(node_t *source, vpn_packet_t *packet)
|
|||
if(n) {
|
||||
if(n == myself) {
|
||||
if(overwrite_mac)
|
||||
memcpy(packet->data, mymac.x, 6);
|
||||
memcpy(packet->data, mymac.x, ETH_ALEN);
|
||||
write_packet(packet);
|
||||
} else
|
||||
send_packet(n, packet);
|
||||
|
|
|
|||
Loading…
Reference in a new issue