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Add DHCPv6 functionality.

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This commit is contained in:
fendo 2014-09-11 16:19:57 +02:00
parent 786a8c4546
commit b3f40f41f7
36 changed files with 2430 additions and 546 deletions
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108
icmp.c
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@ -1,32 +1,18 @@
// 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 <netinet/icmp6.h>
#include <stdio.h>
#include <sys/socket.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <memory.h>
#include <netinet/ip6.h>
#include "dhcp6.h"
#include "l2tpns.h"
#include "pppoe.h"
#include "ipv6_u.h"
static uint16_t _checksum(uint8_t *addr, int count);
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};
@ -85,11 +71,11 @@ static uint16_t _checksum(uint8_t *addr, int count)
for (; count > 1; count -= 2)
{
sum += ntohs(*(uint32_t *) 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)
@ -104,75 +90,75 @@ static uint16_t _checksum(uint8_t *addr, int count)
void send_ipv6_ra(sessionidt s, tunnelidt t, struct in6_addr *ip)
{
struct nd_opt_prefix_info *pinfo;
struct ipv6_pseudo_hdr *phdr;
struct ip6_hdr *p_ip6_hdr;
struct nd_router_advert *p_nra;
uint8_t b[MAXETHER + 20];
uint8_t c[MAXETHER + 20];
struct ipv6_pseudo_hdr pseudo_hdr;
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, s, t, PPPIPV6, 0, 0, 0);
if (!o)
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;
}
*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;
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(o+24, ip, 16); // dest = ip
memcpy(p_ip6_hdr->ip6_dst.s6_addr, ip, 16); // dest = ip
}
else
{
// FF02::1 - all hosts
*(o+24) = 0xFF;
*(o+25) = 2;
*(o+39) = 1;
inet_pton(AF_INET6, "FF02::1", &p_ip6_hdr->ip6_dst.s6_addr);
}
*(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);
// 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_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_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
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;
// // Length of payload (not header)
p_ip6_hdr->ip6_plen = htons(sizeof(*pinfo) + sizeof(*p_nra));
memcpy(c + sizeof(*phdr), o + 40, l - 40);
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
*(uint16_t *)(o+42) = _checksum(c, l - 40 + sizeof(*phdr));
p_nra->nd_ra_cksum = ipv6_checksum(&pseudo_hdr, (uint8_t *) p_nra, (sizeof(*pinfo) + sizeof(*p_nra)));
tunnelsend(b, l + (o-b), t); // send it...
tunnelsend(b, l + (((uint8_t *) p_ip6_hdr)-b), t); // send it...
return;
}