+// L2TPNS: icmp
+
#include <arpa/inet.h>
-#include <netdb.h>
-#include <netinet/in.h>
-#include <asm/types.h>
#include <linux/ip.h>
#include <linux/icmp.h>
-#include <stdio.h>
-#include <sys/socket.h>
+#include <netinet/icmp6.h>
#include <unistd.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <memory.h>
+#include <linux/rtnetlink.h>
+#include <netinet/ip6.h>
+#include "dhcp6.h"
#include "l2tpns.h"
+#include "ipv6_u.h"
-__u16 _checksum(unsigned char *addr, int count);
+static uint16_t _checksum(uint8_t *addr, int count);
-void host_unreachable(ipt destination, u16 id, ipt source, char *packet, int packet_len)
+void host_unreachable(in_addr_t destination, uint16_t id, in_addr_t source, uint8_t *packet, int packet_len)
{
char buf[128] = {0};
struct iphdr *iph;
struct icmphdr *icmp;
- char *data;
int len = 0, on = 1, icmp_socket;
struct sockaddr_in whereto = {0};
- if (!(icmp_socket = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)))
+ if ((icmp_socket = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) < 0)
return;
+
setsockopt(icmp_socket, IPPROTO_IP, IP_HDRINCL, (char *)&on, sizeof(on));
whereto.sin_addr.s_addr = destination;
len = sizeof(struct iphdr);
icmp = (struct icmphdr *)(buf + len);
len += sizeof(struct icmphdr);
- data = (char *)(buf + len);
- len += (packet_len < 64) ? packet_len : 64;
- memcpy(data, packet, (packet_len < 64) ? packet_len : 64);
+
+ /* ip header + first 8 bytes of payload */
+ if (packet_len > (sizeof(struct iphdr) + 8))
+ packet_len = sizeof(struct iphdr) + 8;
+
+ memcpy(buf + len, packet, packet_len);
+ len += packet_len;
iph->tos = 0;
iph->id = id;
icmp->type = ICMP_DEST_UNREACH;
icmp->code = ICMP_HOST_UNREACH;
- icmp->checksum = _checksum((char *)icmp, sizeof(struct icmphdr) + ((packet_len < 64) ? packet_len : 64));
+ icmp->checksum = _checksum((uint8_t *) icmp, sizeof(struct icmphdr) + packet_len);
- iph->check = _checksum((char *)iph, sizeof(struct iphdr));
+ iph->check = _checksum((uint8_t *) iph, sizeof(struct iphdr));
- sendto(icmp_socket, (char *)buf, len, 0, (struct sockaddr *)&whereto, sizeof(struct sockaddr));
+ sendto(icmp_socket, buf, len, 0, (struct sockaddr *)&whereto, sizeof(struct sockaddr));
close(icmp_socket);
}
-__u16 _checksum(unsigned char *addr, int count)
+static uint16_t _checksum(uint8_t *addr, int count)
{
register long sum = 0;
for (; count > 1; count -= 2)
{
- sum += ntohs(*(u32 *)addr);
+ sum += ntohs(*(uint16_t *) addr);
addr += 2;
}
- if (count > 1) sum += *(unsigned char *)addr;
+ if (count > 0) sum += *(unsigned char *)addr;
// take only 16 bits out of the 32 bit sum and add up the carries
while (sum >> 16)
// one's complement the result
sum = ~sum;
- return htons((u16) sum);
+ return htons((uint16_t) sum);
+}
+
+void send_ipv6_ra(sessionidt s, tunnelidt t, struct in6_addr *ip)
+{
+ struct nd_opt_prefix_info *pinfo;
+ struct ip6_hdr *p_ip6_hdr;
+ struct nd_router_advert *p_nra;
+ uint8_t b[MAXETHER + 20];
+ struct ipv6_pseudo_hdr pseudo_hdr;
+ int l;
+
+ LOG(3, s, t, "Sending IPv6 RA\n");
+
+ memset(b, 0, sizeof(b));
+ p_ip6_hdr = (struct ip6_hdr *) makeppp(b, sizeof(b), 0, 0, s, t, PPPIPV6, 0, 0, 0);
+
+ if (!p_ip6_hdr)
+ {
+ LOG(3, s, t, "failed to send IPv6 RA\n");
+ return;
+ }
+
+ p_ip6_hdr->ip6_vfc = 0x60; // IPv6
+ p_ip6_hdr->ip6_plen = 0; // Length of payload (not header) (calculation below)
+ p_ip6_hdr->ip6_nxt = IPPROTO_ICMPV6; // icmp6 is next
+ p_ip6_hdr->ip6_hlim = 255; // Hop limit
+ // IPv6 0xFE80::1
+ inet_pton(AF_INET6, "FE80::1", &p_ip6_hdr->ip6_src.s6_addr);
+
+ if (ip != NULL)
+ {
+ memcpy(p_ip6_hdr->ip6_dst.s6_addr, ip, 16); // dest = ip
+ }
+ else
+ {
+ // FF02::1 - all hosts
+ inet_pton(AF_INET6, "FF02::1", &p_ip6_hdr->ip6_dst.s6_addr);
+ }
+
+ // RA message after Ipv6 header
+ p_nra = (struct nd_router_advert *) &p_ip6_hdr[1];
+ p_nra->nd_ra_type = ND_ROUTER_ADVERT; // RA message (134)
+ p_nra->nd_ra_code = 0; // Code
+ p_nra->nd_ra_cksum = 0; // Checksum
+ p_nra->nd_ra_curhoplimit = 64; // Hop count
+ p_nra->nd_ra_flags_reserved = (ND_RA_FLAG_MANAGED|ND_RA_FLAG_OTHER); // Flags
+ p_nra->nd_ra_router_lifetime = 0xFFFF; // Lifetime
+ p_nra->nd_ra_reachable = 0; // Reachable time
+ p_nra->nd_ra_retransmit = 0; // Retrans timer
+ // Option PI after RA message (rfc4861)
+ pinfo = (struct nd_opt_prefix_info *) &p_nra[1];
+ pinfo->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
+ pinfo->nd_opt_pi_len = 4;
+ pinfo->nd_opt_pi_flags_reserved = ND_OPT_PI_FLAG_ONLINK | ND_OPT_PI_FLAG_AUTO;
+ pinfo->nd_opt_pi_valid_time = htonl(2592000);
+ pinfo->nd_opt_pi_preferred_time = htonl(604800);
+ pinfo->nd_opt_pi_reserved2 = 0;
+ pinfo->nd_opt_pi_prefix_len = 64; // prefix length
+ if (session[s].ipv6address.s6_addr[0])
+ {
+ // MSB 64bits of assigned IPv6 address to user (see radius attribut Framed-IPv6-Address)
+ memcpy(&pinfo->nd_opt_pi_prefix, &session[s].ipv6address.s6_addr[0], 8);
+ }
+ else
+ pinfo->nd_opt_pi_prefix = config->ipv6_prefix;
+
+ // // Length of payload (not header)
+ p_ip6_hdr->ip6_plen = htons(sizeof(*pinfo) + sizeof(*p_nra));
+
+ l = sizeof(*pinfo) + sizeof(*p_nra) + sizeof(*p_ip6_hdr);
+
+ /* Use pseudo hearder for checksum calculation */
+ memset(&pseudo_hdr, 0, sizeof(pseudo_hdr));
+ memcpy(&pseudo_hdr.src, &p_ip6_hdr->ip6_src, 16);
+ memcpy(&pseudo_hdr.dest, &p_ip6_hdr->ip6_dst, 16);
+ pseudo_hdr.ulp_length = htonl(sizeof(*pinfo) + sizeof(*p_nra)); // Lenght whitout Ipv6 header
+ pseudo_hdr.nexthdr = IPPROTO_ICMPV6;
+ // Checksum is over the icmp6 payload plus the pseudo header
+ p_nra->nd_ra_cksum = ipv6_checksum(&pseudo_hdr, (uint8_t *) p_nra, (sizeof(*pinfo) + sizeof(*p_nra)));
+
+ tunnelsend(b, l + (((uint8_t *) p_ip6_hdr)-b), t); // send it...
+ return;
}
projects / l2tpns.git / blobdiff