1 /******************************************************************************
2 Utility to convert a DCCP flow to a TCP flow for DCCP analysis via
5 Copyright (C) 2013 Samuel Jero <sj323707@ohio.edu>
7 This program is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
20 Author: Samuel Jero <sj323707@ohio.edu>
24 1)DCCP MUST use 48 bit sequence numbers
25 2)DCCP Ack packets show up as TCP packets containing one byte
26 ******************************************************************************/
35 #include <sys/types.h>
39 #include <sys/socket.h>
41 #include <netinet/in.h>
42 #include <netinet/in_systm.h>
43 #include <arpa/inet.h>
44 #include <netinet/if_ether.h>
45 #include <netinet/ip.h>
46 #include <netinet/tcp.h>
47 #include <netinet/tcp.h>
48 #include <netinet/udp.h>
52 #include <linux/dccp.h>
53 #include "checksums.h"
56 #define MAX_PACKET 1600 /*Maximum size of TCP packet */
57 #define TBL_SZ 40000 /*Size of Sequence Number Table*/
64 struct pcap_pkthdr *h; /*libpcap header*/
65 u_char *data; /*Packet Data*/
66 int length; /*Packet length*/
67 int id_len; /*Length of IDs*/
68 u_char *src_id; /*Source ID of packet*/
69 u_char *dest_id;/*Destination ID of packet*/
72 /*Constant Packet structure*/
74 const struct pcap_pkthdr *h; /*libpcap header*/
75 const u_char *data; /*Packet Data*/
76 int length; /*Packet length*/
77 int id_len; /*Length of IDs*/
78 u_char *src_id; /*Source ID of packet*/
79 u_char *dest_id;/*Destination ID of packet*/
91 /*Connection Types (i.e. CCID)*/
98 /*Half Connection structure*/
100 int id_len; /*Length of ID*/
101 u_char *id; /*Host ID*/
102 __be16 port; /*Host DCCP port*/
103 struct tbl *table; /*Host Sequence Number Table*/
104 int size; /*Size of Sequence Number Table*/
105 int cur; /*Current TCP Sequence Number*/
106 int high_ack;/*Highest ACK seen*/
107 enum con_state state; /*Connection state*/
108 enum con_type type; /*Connection type*/
111 /*Connection structure*/
113 struct connection *next; /*List pointer*/
114 struct hcon A; /*Host A*/
115 struct hcon B; /*Host B*/
118 /*sequence number table structure */
120 __be32 old; /*DCCP sequence number */
121 u_int32_t new; /*TCP sequence number */
122 int size; /*packet size*/
123 enum dccp_pkt_type type; /*packet type*/
127 extern int debug; /*set to 1 to turn on debugging information*/
128 extern int yellow; /*tcptrace yellow line as currently acked packet*/
129 extern int green; /*tcptrace green line as currently acked packet*/
130 extern int sack; /*add TCP SACKS*/
132 extern struct connection *chead;/*connection list*/
136 * 0) Always print even if debug isn't specified
137 * 1) Errors and warnings... Don't overload the screen with too much output
138 * 2) Notes and per-packet processing info... as verbose as needed
140 void dbgprintf(int level, const char *fmt, ...);
142 /*Function to parse encapsulation*/
143 int do_encap(int link, struct packet *new, const struct const_packet *old);
145 /*Connection functions*/
146 int get_host(u_char *src_id, u_char* dest_id, int id_len, int src_port, int dest_port,
147 int pkt_type, struct hcon **fwd, struct hcon **rev);
148 struct connection *add_connection(u_char *src_id, u_char* dest_id, int id_len,
149 int src_port, int dest_port);
150 int update_state(struct hcon* hst, enum con_state st);
151 void cleanup_connections();
153 /*Half Connection/Sequence number functions*/
154 u_int32_t initialize_hcon(struct hcon *hcn, __be32 initial);
155 u_int32_t add_new_seq(struct hcon *hcn, __be32 num, int size, enum dccp_pkt_type type);
156 u_int32_t convert_ack(struct hcon *hcn, __be32 num, struct hcon *o_hcn);
157 int acked_packet_size(struct hcon *hcn, __be32 num);
158 unsigned int interp_ack_vect(u_char* hdr);