/******************************************************************************
-Author: Samuel Jero
+Utility to convert a DCCP flow to a TCP flow for DCCP analysis via
+ tcptrace. Encapsulation Functions for DCCP conversion to TCP.
-Date: 5/2011
+Copyright (C) 2012 Samuel Jero <sj323707@ohio.edu>
-Description: Encapsulation Functions for DCCP conversion to TCP
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+Author: Samuel Jero <sj323707@ohio.edu>
+Date: 11/2012
******************************************************************************/
#include "dccp2tcp.h"
#include "encap.h"
-#include "pcap/sll.h"
+#include "checksums.h"
+#include <pcap/sll.h>
+#include <pcap/vlan.h>
+#include <netinet/ip6.h>
+#include <netdb.h>
/*Encapsulation start point and link layer selector*/
-int do_encap(int link, struct pcap_pkthdr *h, u_char **nptr, int *nlength, const u_char **optr, int *length)
+int do_encap(int link, struct packet *new, const struct const_packet *old)
{
switch(link){
case DLT_EN10MB:
/*Ethernet*/
- if(!ethernet_encap(h, nptr, nlength, optr, length)){
+ if(!ethernet_encap(new, old)){
return 0;
}
break;
case DLT_RAW:
/*Raw. Just IP*/
- if(!ipv4_encap(h, nptr, nlength, optr, length)){
+ if(!ipv4_encap(new, old)){
return 0;
}
break;
case DLT_LINUX_SLL:
/*Linux Cooked Capture*/
- if(!linux_cooked_encap(h, nptr, nlength, optr, length)){
+ if(!linux_cooked_encap(new, old)){
return 0;
}
break;
}
/*Adjust libpcap header*/
- if(h->caplen >= h->len || h->caplen >= *nlength){
- h->caplen=*nlength;
+ if(new->h->caplen >= new->h->len || new->h->caplen >= new->length){
+ new->h->caplen=new->length;
}
- h->len=*nlength;
+ new->h->len=new->length;
return 1;
}
/*Standard Ethernet Encapsulation*/
-int ethernet_encap(struct pcap_pkthdr *h, u_char **nptr, int *nlength, const u_char **optr, int *length)
+int ethernet_encap(struct packet *new, const struct const_packet *old)
{
- struct ether_header *ethh;
- int next_len;
- int next_nlen;
- u_char *next_nptr;
- const u_char *next_optr;
+ struct ether_header *ethh;
+ struct const_packet nold;
+ struct packet nnew;
/*Safety checks*/
- if(!h || !nptr || !nlength || !optr || !length || !*nptr || !*optr){
+ if(!new || !old || !new->data || !old->data || !new->h || !old->h){
dbgprintf(0,"Error: Ethernet Encapsulation Function given bad data!\n");
return 0;
}
- if(*length < sizeof(struct ether_header) || *nlength < sizeof(struct ether_header)){
+ if(old->length < sizeof(struct ether_header) || new->length < sizeof(struct ether_header)){
dbgprintf(0, "Error: Ethernet Encapsulation Function given packet of wrong size!\n");
return 0;
}
/*Copy Ethernet header over*/
- memcpy(*nptr, *optr, sizeof(struct ether_header));
+ memcpy(new->data, old->data, sizeof(struct ether_header));
/*Cast Pointer*/
- ethh=(struct ether_header*)(*nptr);
+ ethh=(struct ether_header*)(new->data);
/*Adjust pointers and lengths*/
- next_optr= *optr+ sizeof(struct ether_header);
- next_nptr= *nptr+ sizeof(struct ether_header);
- next_len= *length- sizeof(struct ether_header);
- next_nlen= *nlength- sizeof(struct ether_header);
+ nold.data= old->data+ sizeof(struct ether_header);
+ nnew.data= new->data + sizeof(struct ether_header);
+ nold.length= old->length - sizeof(struct ether_header);
+ nnew.length= new->length - sizeof(struct ether_header);
+ nnew.h=new->h;
+ nold.h=old->h;
+ nnew.print_id=NULL;
+ nnew.dest_id=NULL;
+ nnew.src_id=NULL;
+ nnew.id_len=0;
+ nold.print_id=NULL;
+ nold.dest_id=NULL;
+ nold.src_id=NULL;
+ nold.id_len=0;
/*Select Next Protocol*/
switch(ntohs(ethh->ether_type)){
case ETHERTYPE_IP:
- if(!ipv4_encap(h, &next_nptr, &next_nlen, &next_optr, &next_len)){
+ if(!ipv4_encap(&nnew, &nold)){
+ return 0;
+ }
+ break;
+ case ETHERTYPE_IPV6:
+ if(!ipv6_encap(&nnew, &nold)){
+ return 0;
+ }
+ break;
+ case ETHERTYPE_VLAN:
+ if(!ethernet_vlan_encap(&nnew, &nold)){
return 0;
}
break;
}
/*Adjust length*/
- *nlength=next_nlen + sizeof(struct ether_header);
+ new->length=nnew.length + sizeof(struct ether_header);
+return 1;
+}
+
+/*Ethernet 802.1Q VLAN Encapsulation*/
+int ethernet_vlan_encap(struct packet *new, const struct const_packet *old)
+{
+ struct vlan_tag *tag;
+ struct const_packet nold;
+ struct packet nnew;
+
+ /*Safety checks*/
+ if(!new || !old || !new->data || !old->data || !new->h || !old->h){
+ dbgprintf(0,"Error: Ethernet VLAN Encapsulation Function given bad data!\n");
+ return 0;
+ }
+ if(old->length < sizeof(struct vlan_tag) || new->length < sizeof(struct vlan_tag)){
+ dbgprintf(0, "Error: Ethernet VLAN Encapsulation Function given packet of wrong size!\n");
+ return 0;
+ }
+
+ /*Copy VLAN tag over*/
+ memcpy(new->data, old->data, sizeof(struct vlan_tag));
+
+ /*Cast Pointer*/
+ tag=(struct vlan_tag*)(new->data);
+
+ /*Adjust pointers and lengths*/
+ nold.data= old->data+ sizeof(struct vlan_tag);
+ nnew.data= new->data + sizeof(struct vlan_tag);
+ nold.length= old->length - sizeof(struct vlan_tag);
+ nnew.length= new->length - sizeof(struct vlan_tag);
+ nnew.h=new->h;
+ nold.h=old->h;
+ nnew.print_id=NULL;
+ nnew.dest_id=NULL;
+ nnew.src_id=NULL;
+ nnew.id_len=0;
+ nold.print_id=NULL;
+ nold.dest_id=NULL;
+ nold.src_id=NULL;
+ nold.id_len=0;
+
+ /*Select Next Protocol*/
+ switch(ntohs(tag->vlan_tci)){
+ case ETHERTYPE_IP:
+ if(!ipv4_encap(&nnew, &nold)){
+ return 0;
+ }
+ break;
+ case ETHERTYPE_IPV6:
+ if(!ipv6_encap(&nnew, &nold)){
+ return 0;
+ }
+ break;
+ case ETHERTYPE_VLAN:
+ if(!ethernet_vlan_encap(&nnew, &nold)){
+ return 0;
+ }
+ break;
+ default:
+ dbgprintf(1, "Unknown Next Protocol at Ethernet VLAN tag\n");
+ return 0;
+ break;
+ }
+
+ /*Adjust length*/
+ new->length=nnew.length + sizeof(struct vlan_tag);
+return 1;
+}
+
+/*IPv6 Encapsulation*/
+int ipv6_encap(struct packet *new, const struct const_packet *old)
+{
+ struct ip6_hdr *iph;
+ struct packet nnew;
+ struct const_packet nold;
+
+ /*Safety checks*/
+ if(!new || !old || !new->data || !old->data || !new->h || !old->h){
+ dbgprintf(0,"Error: IPv6 Encapsulation Function given bad data!\n");
+ return 0;
+ }
+ if(old->length < sizeof(struct ip6_hdr) || new->length < sizeof(struct ip6_hdr)){
+ dbgprintf(0, "Error: IPv6 Encapsulation Function given packet of wrong size!\n");
+ return 0;
+ }
+
+ /*Copy IPv6 header over*/
+ memcpy(new->data, old->data, sizeof(struct ip6_hdr));
+
+ /*Cast Pointer*/
+ iph=(struct ip6_hdr*)(new->data);
+
+ /*Adjust pointers and lengths*/
+ nold.data= old->data + sizeof(struct ip6_hdr);
+ nnew.data= new->data +sizeof(struct ip6_hdr);
+ nold.length= old->length - sizeof(struct ip6_hdr);
+ nnew.length= new->length - sizeof(struct ip6_hdr);
+ nnew.h=new->h;
+ nold.h=old->h;
+ nnew.print_id=print_ipv6;
+ nold.print_id=print_ipv6;
+ nnew.id_len=16;
+ nold.id_len=16;
+
+ /*Confirm that this is IPv6*/
+ if((ntohl(iph->ip6_ctlun.ip6_un1.ip6_un1_flow) & (0xF0000000)) == (60000000)){
+ dbgprintf(1, "Note: Packet is not IPv6\n");
+ return 0;
+ }
+
+ /*Select Next Protocol*/
+ switch(iph->ip6_ctlun.ip6_un1.ip6_un1_nxt){
+ case 33:
+ /*DCCP*/
+ nnew.src_id=malloc(nnew.id_len);
+ nnew.dest_id=malloc(nnew.id_len);
+ nold.src_id=malloc(nold.id_len);
+ nold.dest_id=malloc(nold.id_len);
+ if(nnew.src_id==NULL||nnew.dest_id==NULL ||
+ nold.src_id==NULL||nold.dest_id==NULL){
+ dbgprintf(0,"Error: Couldn't allocate Memory\n");
+ exit(1);
+ }
+ memcpy(nnew.src_id,&iph->ip6_src,nnew.id_len);
+ memcpy(nnew.dest_id,&iph->ip6_dst,nnew.id_len);
+ memcpy(nold.src_id,&iph->ip6_src,nold.id_len);
+ memcpy(nold.dest_id,&iph->ip6_dst,nold.id_len);
+ if(!convert_packet(&nnew, &nold)){
+ return 0;
+ }
+ break;
+ default:
+ dbgprintf(1, "Unknown Next Protocol at IPv6\n");
+ return 0;
+ break;
+ }
+
+ /*set ip to indicate that TCP is next protocol*/
+ iph->ip6_ctlun.ip6_un1.ip6_un1_nxt=6;
+
+ /*Determine if computed length is reasonable*/
+ if(nnew.length > 0xFFFF){
+ dbgprintf(1, "Error: Given TCP data length is too large for an IPv6 packet!\n");
+ return 0;
+ }
+
+ /*Adjust IPv6 header to account for packet's total length*/
+ iph->ip6_ctlun.ip6_un1.ip6_un1_plen=htons(nnew.length);
+
+ /*Adjust length*/
+ new->length=nnew.length + sizeof(struct ip6_hdr);
+
+ /*Cleanup*/
+ free(nnew.dest_id);
+ free(nnew.src_id);
+ free(nold.dest_id);
+ free(nold.src_id);
return 1;
}
/*IPv4 Encapsulation*/
-int ipv4_encap(struct pcap_pkthdr *h, u_char **nptr, int *nlength, const u_char **optr, int *length)
+int ipv4_encap(struct packet *new, const struct const_packet *old)
{
- struct iphdr *iph;
- int next_len;
- int next_nlen;
- u_char *next_nptr;
- const u_char *next_optr;
+ struct iphdr *iph;
+ struct packet nnew;
+ struct const_packet nold;
/*Safety checks*/
- if(!h || !nptr || !nlength || !optr || !length || !*nptr || !*optr){
+ if(!new || !old || !new->data || !old->data || !new->h || !old->h){
dbgprintf(0,"Error: IPv4 Encapsulation Function given bad data!\n");
return 0;
}
- if(*length < sizeof(struct iphdr) || *nlength < sizeof(struct iphdr)){
+ if(old->length < sizeof(struct iphdr) || new->length < sizeof(struct iphdr)){
dbgprintf(0, "Error: IPv4 Encapsulation Function given packet of wrong size!\n");
return 0;
}
/*Copy IPv4 header over*/
- memcpy(*nptr, *optr, sizeof(struct iphdr));
+ memcpy(new->data, old->data, sizeof(struct iphdr));
/*Cast Pointer*/
- iph=(struct iphdr*)(*nptr);
+ iph=(struct iphdr*)(new->data);
/*Adjust pointers and lengths*/
- next_optr= *optr +iph->ihl*4;
- next_nptr= *nptr +iph->ihl*4;
- next_len= *length -iph->ihl*4;
- next_nlen= *nlength-iph->ihl*4;
+ nold.data= old->data +iph->ihl*4;
+ nnew.data= new->data +iph->ihl*4;
+ nold.length= old->length -iph->ihl*4;
+ nnew.length= new->length -iph->ihl*4;
+ nnew.h=new->h;
+ nold.h=old->h;
+ nnew.print_id=print_ipv4;
+ nold.print_id=print_ipv4;
+ nnew.id_len=4;
+ nold.id_len=4;
/*Confirm that this is IPv4*/
if(iph->version!=4){
/*Select Next Protocol*/
switch(iph->protocol){
- case 0x21:
+ case 33:
/*DCCP*/
- if(!convert_packet(h, &next_nptr, &next_nlen, &next_optr, &next_len)){
+ nnew.src_id=malloc(nnew.id_len);
+ nnew.dest_id=malloc(nnew.id_len);
+ nold.src_id=malloc(nold.id_len);
+ nold.dest_id=malloc(nold.id_len);
+ if(nnew.src_id==NULL||nnew.dest_id==NULL||
+ nold.src_id==NULL||nold.dest_id==NULL){
+ dbgprintf(0,"Error: Couldn't allocate Memory\n");
+ exit(1);
+ }
+ memcpy(nnew.src_id,&iph->saddr,nnew.id_len);
+ memcpy(nnew.dest_id,&iph->daddr,nnew.id_len);
+ memcpy(nold.src_id,&iph->saddr,nold.id_len);
+ memcpy(nold.dest_id,&iph->daddr,nold.id_len);
+ if(!convert_packet(&nnew, &nold)){
return 0;
}
break;
iph->check=htonl(0);
/*Adjust length*/
- *nlength=next_nlen + iph->ihl*4;
+ new->length=nnew.length + iph->ihl*4;
/*Determine if computed length is reasonable*/
- if(*nlength > 0xFFFF){
+ if(nnew.length > 0xFFFF){
dbgprintf(1, "Error: Given TCP header+data length is too large for an IPv4 packet!\n");
return 0;
}
/*Adjust IPv4 header to account for packet's total length*/
- iph->tot_len=htons(*nlength);
+ iph->tot_len=htons(new->length);
+
+ /*Compute IPv4 Checksum*/
+ iph->check=0;
+ iph->check=ipv4_chksum(new->data,iph->ihl*4);
+
+ /*Cleanup*/
+ free(nnew.src_id);
+ free(nnew.dest_id);
+ free(nold.src_id);
+ free(nold.dest_id);
return 1;
}
-int linux_cooked_encap(struct pcap_pkthdr *h, u_char **nptr, int *nlength, const u_char **optr, int *length)
+int linux_cooked_encap(struct packet *new, const struct const_packet *old)
{
- struct sll_header *slh;
- int next_len;
- int next_nlen;
- u_char *next_nptr;
- const u_char *next_optr;
+ struct sll_header *slh;
+ struct packet nnew;
+ struct const_packet nold;
/*Safety checks*/
- if(!h || !nptr || !nlength || !optr || !length || !*nptr || !*optr){
+ if(!new|| !old || !new->data || !old->data || !new->h || !old->h){
dbgprintf(0,"Error: SLL Encapsulation Function given bad data!\n");
return 0;
}
- if(*length < sizeof(struct sll_header) || *nlength < sizeof(struct sll_header)){
+ if(old->length < sizeof(struct sll_header) || new->length < sizeof(struct sll_header)){
dbgprintf(0, "Error: SLL Encapsulation Function given packet of wrong size!\n");
return 0;
}
/*Copy SLL header over*/
- memcpy(*nptr, *optr, sizeof(struct sll_header));
+ memcpy(new->data, old->data, sizeof(struct sll_header));
/*Cast Pointer*/
- slh=(struct sll_header*)(*nptr);
+ slh=(struct sll_header*)(new->data);
/*Adjust pointers and lengths*/
- next_optr= *optr + sizeof(struct sll_header);
- next_nptr= *nptr + sizeof(struct sll_header);
- next_len= *length - sizeof(struct sll_header);
- next_nlen= *nlength- sizeof(struct sll_header);
+ nold.data= old->data + sizeof(struct sll_header);
+ nnew.data= new->data + sizeof(struct sll_header);
+ nold.length= old->length - sizeof(struct sll_header);
+ nnew.length= new->length- sizeof(struct sll_header);
+ nnew.h=new->h;
+ nold.h=old->h;
+ nnew.print_id=NULL;
+ nnew.dest_id=NULL;
+ nnew.src_id=NULL;
+ nnew.id_len=0;
+ nold.print_id=NULL;
+ nold.dest_id=NULL;
+ nold.src_id=NULL;
+ nold.id_len=0;
/*Confirm that this is SLL*/
if(ntohs(slh->sll_pkttype) > 4){
/*Select Next Protocol*/
switch(ntohs(slh->sll_protocol)){
case ETHERTYPE_IP:
- if(!ipv4_encap(h, &next_nptr, &next_nlen, &next_optr, &next_len)){
+ if(!ipv4_encap(&nnew, &nold)){
+ return 0;
+ }
+ break;
+ case ETHERTYPE_IPV6:
+ if(!ipv6_encap(&nnew, &nold)){
return 0;
}
break;
}
/*Adjust length*/
- *nlength=next_nlen + sizeof(struct sll_header);
+ new->length=nnew.length + sizeof(struct sll_header);
return 1;
}
+
+
+char *print_ipv6(char* buf, int len, u_char* id, int id_len)
+{
+ struct sockaddr_in6 sa;
+
+ if(buf==NULL){
+ return NULL;
+ }
+
+ memcpy(&sa.sin6_addr, id, id_len);
+ sa.sin6_family=AF_INET6;
+ if(getnameinfo((struct sockaddr*)&sa, sizeof(struct sockaddr_in6),
+ buf, len, NULL,0,NI_NUMERICHOST)<0){
+ return NULL;
+ }
+ return buf;
+}
+
+char *print_ipv4(char* buf, int len, u_char* id, int id_len)
+{
+ struct sockaddr_in sa;
+
+ if(buf==NULL){
+ return NULL;
+ }
+
+ memcpy(&sa.sin_addr, id, id_len);
+ sa.sin_family=AF_INET;
+ if(getnameinfo((struct sockaddr*)&sa, sizeof(struct sockaddr_in),
+ buf, len, NULL,0,NI_NUMERICHOST)<0){
+ return NULL;
+ }
+ return buf;
+}
projects / dccp2tcp / blobdiff