+// L2TPNS: icmp
+
+char const *cvs_id_icmp = "$Id: icmp.c,v 1.9 2005/07/31 10:04:10 bodea Exp $";
+
#include <arpa/inet.h>
#include <netdb.h>
#include <netinet/in.h>
#include <asm/types.h>
#include <linux/ip.h>
#include <linux/icmp.h>
+#include <netinet/icmp6.h>
#include <stdio.h>
#include <sys/socket.h>
#include <unistd.h>
#include "l2tpns.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)
+struct ipv6_pseudo_hdr {
+ struct in6_addr src;
+ struct in6_addr dest;
+ uint32_t ulp_length;
+ uint32_t zero : 24;
+ uint32_t nexthdr : 8;
+};
+
+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(*(uint32_t *) addr);
addr += 2;
}
// one's complement the result
sum = ~sum;
- return htons((u16) sum);
+ return htons((uint16_t) sum);
+}
+
+void send_ipv6_ra(tunnelidt t, sessionidt s, struct in6_addr *ip)
+{
+ struct nd_opt_prefix_info *pinfo;
+ struct ipv6_pseudo_hdr *phdr;
+ uint8_t b[MAXETHER + 20];
+ uint8_t c[MAXETHER + 20];
+ int l;
+ uint8_t *o;
+
+ LOG(3, s, t, "Sending IPv6 RA\n");
+
+ memset(b, 0, sizeof(b));
+ o = makeppp(b, sizeof(b), 0, 0, t, s, PPPIPV6);
+
+ if (!o)
+ {
+ LOG(3, s, t, "failed to send IPv6 RA\n");
+ return;
+ }
+
+ *o = 0x60; // IPv6
+ *(o+1) = 0;
+ *(o+5) = 48; // Length of payload (not header)
+ *(o+6) = 58; // icmp6 is next
+ *(o+7) = 255; // Hop limit
+ memset(o+8, 0, 16); // source = FE80::1
+ *(o+8) = 0xFE;
+ *(o+9) = 0x80;
+ *(o+23) = 1;
+ if (ip != NULL)
+ memcpy(o+24, ip, 16); // dest = ip
+ else
+ {
+ // FF02::1 - all hosts
+ *(o+24) = 0xFF;
+ *(o+25) = 2;
+ *(o+39) = 1;
+ }
+ *(o+40) = 134; // RA message
+ *(o+41) = 0; // Code
+ *(o+42) = *(o+43) = 0; // Checksum
+ *(o+44) = 64; // Hop count
+ *(o+45) = 0; // Flags
+ *(o+46) = *(o+47) = 255; // Lifetime
+ *(uint32_t *)(o+48) = 0; // Reachable time
+ *(uint32_t *)(o+52) = 0; // Retrans timer
+ pinfo = (struct nd_opt_prefix_info *)(o+56);
+ pinfo->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
+ pinfo->nd_opt_pi_len = 4;
+ pinfo->nd_opt_pi_prefix_len = 64; // prefix length
+ pinfo->nd_opt_pi_flags_reserved = ND_OPT_PI_FLAG_ONLINK;
+ pinfo->nd_opt_pi_flags_reserved |= 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 = config->ipv6_prefix;
+ l = sizeof(*pinfo) + 56;
+
+ memset(c, 0, sizeof(c));
+ phdr = (struct ipv6_pseudo_hdr *) c;
+ memcpy(&phdr->src, o+8, 16);
+ memcpy(&phdr->dest, o+24, 16);
+ phdr->ulp_length = htonl(l - 40);
+ phdr->nexthdr = IPPROTO_ICMPV6;
+
+ memcpy(c + sizeof(*phdr), o + 40, l - 40);
+
+ // Checksum is over the icmp6 payload plus the pseudo header
+ *(uint16_t *)(o+42) = _checksum(c, l - 40 + sizeof(*phdr));
+
+ tunnelsend(b, l + (o-b), t); // send it...
+ return;
}
projects / l2tpns.git / blobdiff