int scamper_ip4_build(scamper_probe_t *pr, uint8_t *buf, size_t *len)
{
scamper_probe_ipopt_t *opt;
struct ip *ip;
size_t off, ip4hlen;
int i, j;
if(scamper_ip4_hlen(pr, &ip4hlen) != 0)
return -1;
if(ip4hlen > *len)
{
*len = ip4hlen;
return -1;
}
ip = (struct ip *)buf;
off = sizeof(struct ip);
#ifndef _WIN32
ip->ip_v = 4;
ip->ip_hl = (ip4hlen / 4);
#else
ip->ip_vhl = 0x40 | (ip4hlen / 4);
#endif
if((pr->pr_ip_off & IP_OFFMASK) != 0 || pr->pr_no_trans)
ip->ip_len = htons(ip4hlen + pr->pr_len);
else if(pr->pr_ip_proto == IPPROTO_ICMP || pr->pr_ip_proto == IPPROTO_UDP)
ip->ip_len = htons(ip4hlen + 8 + pr->pr_len);
else if(pr->pr_ip_proto == IPPROTO_TCP)
ip->ip_len = htons(ip4hlen + scamper_tcp4_hlen(pr) + pr->pr_len);
else
{
scamper_debug(__func__, "unimplemented pr %d", pr->pr_ip_proto);
return -1;
}
ip->ip_tos = pr->pr_ip_tos;
ip->ip_id = htons(pr->pr_ip_id);
ip->ip_off = htons(pr->pr_ip_off);
ip->ip_ttl = pr->pr_ip_ttl;
ip->ip_p = pr->pr_ip_proto;
ip->ip_sum = 0;
memcpy(&ip->ip_src, pr->pr_ip_src->addr, sizeof(ip->ip_src));
memcpy(&ip->ip_dst, pr->pr_ip_dst->addr, sizeof(ip->ip_dst));
for(i=0; i<pr->pr_ipoptc; i++)
{
opt = &pr->pr_ipopts[i];
if(opt->type == SCAMPER_PROBE_IPOPTS_V4RR)
{
memset(buf+off+3, 0, 37);
buf[off+0] = 7;
buf[off+1] = 39;
buf[off+2] = 4;
off = 60;
}
else if(opt->type == SCAMPER_PROBE_IPOPTS_V4TSPS ||
opt->type == SCAMPER_PROBE_IPOPTS_V4TSO ||
opt->type == SCAMPER_PROBE_IPOPTS_V4TSAA)
{
buf[off+0] = 68;
buf[off+2] = 5;
if(opt->type == SCAMPER_PROBE_IPOPTS_V4TSPS)
{
buf[off+1] = (opt->opt_v4tsps_ipc * 4 * 2) + 4;
buf[off+3] = 3;
off += 4;
for(j=0; j<opt->opt_v4tsps_ipc; j++)
{
memcpy(buf+off, &opt->opt_v4tsps_ips[j], 4);
off += 4;
memset(buf+off, 0, 4);
off += 4;
}
}
else if(opt->type == SCAMPER_PROBE_IPOPTS_V4TSO)
{
buf[off+1] = 40;
memset(buf+off+3, 0, 41);
off += 40;
}
else if(opt->type == SCAMPER_PROBE_IPOPTS_V4TSAA)
{
buf[off+1] = 36;
buf[off+3] = 1;
memset(buf+off+4, 0, 36);
off += 36;
}
}
else if(opt->type == SCAMPER_PROBE_IPOPTS_QUICKSTART)
{
assert(opt->opt_qs_func <= 0xf);
assert(opt->opt_qs_rate <= 0xf);
buf[off+0] = 25;
buf[off+1] = 8;
buf[off+2] = (opt->opt_qs_func << 4) | opt->opt_qs_rate;
buf[off+3] = opt->opt_qs_ttl;
bytes_htonl(&buf[off+4], opt->opt_qs_nonce << 2);
off += 8;
}
else return -1;
}
assert(off == ip4hlen);
ip->ip_sum = in_cksum(ip, ip4hlen);
*len = off;
return 0;
}
static void probe_print(scamper_probe_t *probe)
{
size_t iphl;
char tcp[16];
char pos[32];
char addr[128];
char icmp[16];
char tos[8];
assert(probe->pr_ip_dst != NULL);
scamper_addr_tostr(probe->pr_ip_dst, addr, sizeof(addr));
tos[0] = '\0';
icmp[0] = '\0';
if(probe->pr_ip_proto == IPPROTO_TCP)
{
if((probe->pr_ip_tos & IPTOS_ECN_CE) == IPTOS_ECN_CE)
snprintf(tos, sizeof(tos), ", ce");
else if(probe->pr_ip_tos & IPTOS_ECN_ECT1)
snprintf(tos, sizeof(tos), ", ect1");
else if(probe->pr_ip_tos & IPTOS_ECN_ECT0)
snprintf(tos, sizeof(tos), ", ect0");
}
if(probe->pr_ip_dst->type == SCAMPER_ADDR_TYPE_IPV4)
{
if(scamper_ip4_hlen(probe, &iphl) != 0)
return;
if((probe->pr_ip_off & IP_OFFMASK) != 0)
{
scamper_debug("tx", "frag %s %04x:%d ttl %d, len %d",
addr, probe->pr_ip_id, probe->pr_ip_off << 3,
probe->pr_ip_ttl, iphl + probe->pr_len);
return;
}
switch(probe->pr_ip_proto)
{
case IPPROTO_UDP:
scamper_debug("tx", "udp %s, ttl %d, %d:%d, len %d",
addr, probe->pr_ip_ttl, probe->pr_udp_sport,
probe->pr_udp_dport, iphl + 8 + probe->pr_len);
break;
case IPPROTO_TCP:
scamper_debug("tx",
"tcp %s%s, ttl %d, %d:%d%s, ipid %04x, %s, len %d",
addr, tos, probe->pr_ip_ttl,
probe->pr_tcp_sport, probe->pr_tcp_dport,
tcp_flags(tcp, sizeof(tcp), probe),
probe->pr_ip_id, tcp_pos(pos, sizeof(pos), probe),
iphl + scamper_tcp4_hlen(probe) + probe->pr_len);
break;
case IPPROTO_ICMP:
if(probe->pr_icmp_type == ICMP_ECHO)
{
if(probe->pr_icmp_sum != 0)
{
snprintf(icmp, sizeof(icmp), ", sum %04x",
ntohs(probe->pr_icmp_sum));
}
scamper_debug("tx", "icmp %s echo, ttl %d%s, seq %d, len %d",
addr, probe->pr_ip_ttl, icmp, probe->pr_icmp_seq,
iphl + 8 + probe->pr_len);
}
else if(probe->pr_icmp_type == ICMP_UNREACH)
{
if(probe->pr_icmp_code == ICMP_UNREACH_NEEDFRAG)
snprintf(icmp,sizeof(icmp),"ptb %d", probe->pr_icmp_mtu);
else
snprintf(icmp,sizeof(icmp),"unreach %d", probe->pr_icmp_code);
scamper_debug("tx", "icmp %s %s, len %d",
addr, icmp, iphl + 8 + probe->pr_len);
}
else
{
scamper_debug("tx", "icmp %s type %d, code %d, len %d",
addr, probe->pr_icmp_type, probe->pr_icmp_code,
iphl + 8 + probe->pr_len);
}
break;
}
}
else if(probe->pr_ip_dst->type == SCAMPER_ADDR_TYPE_IPV6)
{
if(scamper_ip6_hlen(probe, &iphl) != 0)
return;
if(probe->pr_ip_off != 0)
{
scamper_debug("tx", "frag %s off %04x, ttl %d, len %d",
addr, probe->pr_ip_off, probe->pr_ip_ttl,
iphl + probe->pr_len);
return;
}
switch(probe->pr_ip_proto)
{
case IPPROTO_UDP:
scamper_debug("tx", "udp %s, ttl %d, %d:%d, len %d",
addr, probe->pr_ip_ttl, probe->pr_udp_sport,
probe->pr_udp_dport, iphl + 8 + probe->pr_len);
break;
case IPPROTO_TCP:
scamper_debug("tx", "tcp %s%s, ttl %d, %d:%d%s, %s, len %d",
addr, tos, probe->pr_ip_ttl,
probe->pr_tcp_sport, probe->pr_tcp_dport,
tcp_flags(tcp, sizeof(tcp), probe),
tcp_pos(pos, sizeof(pos), probe),
iphl + scamper_tcp6_hlen(probe) + probe->pr_len);
break;
case IPPROTO_ICMPV6:
if(probe->pr_icmp_type == ICMP6_ECHO_REQUEST)
{
if(probe->pr_icmp_sum != 0)
{
snprintf(icmp, sizeof(icmp), ", sum %04x",
ntohs(probe->pr_icmp_sum));
}
scamper_debug("tx", "icmp %s echo, ttl %d%s, seq %d, len %d",
addr, probe->pr_ip_ttl, icmp, probe->pr_icmp_seq,
iphl + 8 + probe->pr_len);
}
else if(probe->pr_icmp_type == ICMP6_PACKET_TOO_BIG)
{
scamper_debug("tx", "icmp %s ptb %d, len %d", addr,
probe->pr_icmp_mtu, iphl + 8 + probe->pr_len);
}
else if(probe->pr_icmp_type == ICMP6_DST_UNREACH)
{
scamper_debug("tx", "icmp %s unreach %d, len %d", addr,
probe->pr_icmp_code, iphl + 8 + probe->pr_len);
}
else
{
scamper_debug("tx", "icmp %s type %d, code %d, len %d",
addr, probe->pr_icmp_type, probe->pr_icmp_code,
iphl + 8 + probe->pr_len);
}
break;
}
}
return;
}
