packetHeader.h File Reference

#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <linux/if_ether.h>
#include <net/if_arp.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>

Go to the source code of this file.

Classes
struct	rst_arphdr
	ARP header specialized for Ethernet at layer 2 and IP at layer 3. More...
struct	rst_buf
Defines
#define	RST_ETH_HDR_LEN   14
#define	RST_ARP_HDR_LEN   28
#define	RST_IP_HDR_LEN   20
#define	RST_TCP_HDR_LEN   20
#define	RST_UDP_HDR_LEN   8
#define	RST_ICMP_HDR_LEN   8
#define	RST_ETH_HDR   0x01
#define	RST_ARP_HDR   0x02
#define	RST_IP_HDR   0x04
#define	RST_ICMP_HDR   0x20
#define	RST_TCP_HDR   0x08
#define	RST_UDP_HDR   0x10
Functions
void	rst_initEth (struct ethhdr *, unsigned char *, unsigned char *, unsigned short)
	Initialize an Ethernet header.
void	rst_initARPrequest (struct rst_arphdr *, unsigned char *, unsigned int, unsigned int)
	Initialize an ARP request header.
void	rst_initARPreply (struct rst_arphdr *, unsigned char *, unsigned int, unsigned char *, unsigned int)
	Initialize an ARP reply header.
void	rst_initIP (struct iphdr *, unsigned short, unsigned char, unsigned int, unsigned int)
	Initialize an IP header.
void	rst_initICMP (struct icmphdr *, unsigned char)
	Initialize an ICMP header.
void	rst_initTCP (struct tcphdr *, unsigned short, unsigned short)
	Initialize a TCP header.
void	rst_initUDP (struct udphdr *, unsigned short, unsigned short, unsigned short)
	Initialize a UDP header.
void	rst_initRbuf (struct rst_buf *, unsigned char *, int, unsigned int)
	Initialize an rst_buf.
int	rst_verifyRbuf (struct rst_buf *)
	Check that an rst_buf is safe, in the sense that a call to rst_htonp will not abort.
void	rst_htonp (struct rst_buf *)
	Do host-to-network byte swapping and checksum calculation.
void	rst_ntohp (struct rst_buf *)
	Parse an incoming packet and do network-to-host byte swapping.
unsigned char *	rst_ethData (struct rst_buf *)
	Get the address of the Ethernet header in rBuf.
unsigned char *	rst_ipData (struct rst_buf *)
	Get the address of the IP header in rBuf.
unsigned char *	rst_icmpData (struct rst_buf *)
	Get the address of the ICMP header in rBuf.
unsigned char *	rst_tcpData (struct rst_buf *)
	Get the address of the TCP header in rBuf.
unsigned char *	rst_udpData (struct rst_buf *)
	Get the address of the UDP header in rBuf.
unsigned short	rst_getIPchecksum (struct iphdr *)
	Compute an IP checksum.
unsigned short	rst_getICMPchecksum (struct icmphdr *, unsigned short)
	Compute an ICMP checksum.
unsigned short	rst_getTCPchecksum (struct iphdr *, struct tcphdr *, unsigned short)
	Compute an TCP checksum.
unsigned short	rst_getUDPchecksum (struct iphdr *, struct udphdr *, unsigned short)
	Compute an UDP checksum.

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Define Documentation

#define RST_ARP_HDR   0x02

#define RST_ARP_HDR_LEN   28

#define RST_ETH_HDR   0x01

#define RST_ETH_HDR_LEN   14

#define RST_ICMP_HDR   0x20

#define RST_ICMP_HDR_LEN   8

#define RST_IP_HDR   0x04

#define RST_IP_HDR_LEN   20

#define RST_TCP_HDR   0x08

#define RST_TCP_HDR_LEN   20

#define RST_UDP_HDR   0x10

#define RST_UDP_HDR_LEN   8

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Function Documentation

unsigned char* rst_ethData (  struct rst_buf *   )

Get the address of the Ethernet header in rBuf.

unsigned short rst_getICMPchecksum (  struct icmphdr *  , unsigned  short )

Compute an ICMP checksum.

unsigned short rst_getIPchecksum (  struct iphdr *   )

Compute an IP checksum.

unsigned short rst_getTCPchecksum (  struct iphdr *  , struct tcphdr *  , unsigned  short )

Compute an TCP checksum.

unsigned short rst_getUDPchecksum (  struct iphdr *  , struct udphdr *  , unsigned  short )

Compute an UDP checksum.

void rst_htonp (  struct rst_buf *  rBuf  )

Do host-to-network byte swapping and checksum calculation. Parameters: rBuf  an initialized rst_buf Precondition: rBuf.buf[0..rBuf.bufLen-1] is allocated for each non-null pointer p in rBuf, *p is in rBuf.buf[0..rBuf.bufLen-1] for each non-null pointer p in rBuf, any length fields in *p specify a header that lies in rBuf.buf[0..rBuf.bufLen-1] Postcondition: for each non-null pointer p in rBuf, appropriate byte swapping and checksum calculation has been done.

unsigned char* rst_icmpData (  struct rst_buf *   )

Get the address of the ICMP header in rBuf.

void rst_initARPreply (  struct rst_arphdr *  arphdr, unsigned char *  senderMAC, unsigned int  senderIP, unsigned char *  targetMAC, unsigned int  targetIP )

Initialize an ARP reply header. Parameters: arphdr  address of header to be initialized senderMAC  sender's MAC address senderIP  sender's IP address targetMAC  target's MAC address targetIP  target's IP address Precondition: arphdr points to at least RST_ARP_HDR_LEN bytes senderMAC points to at least 6 bytes targetMAC points to at least 6 bytes Postcondition: arphdr initialized, in host byte order

void rst_initARPrequest (  struct rst_arphdr *  arphdr, unsigned char *  senderMAC, unsigned int  senderIP, unsigned int  targetIP )

Initialize an ARP request header. Parameters: arphdr  address of header to be initialized senderMAC  sender's MAC address senderIP  sender's IP address targetIP  target's IP address Precondition: arphdr points to at least RST_ARP_HDR_LEN bytes senderMAC points to at least 6 bytes Postcondition: arphdr initialized, in host byte order

void rst_initEth (  struct ethhdr *  ethhdr, unsigned char *  dst, unsigned char *  src, unsigned short  proto )

Initialize an Ethernet header. Parameters: ethhdr  address of header to be initialized dst  destination MAC address src  source MAC address proto  next layer protocol Precondition: ethhdr points to at least RST_ETH_HDR_LEN bytes dst points to at least 6 bytes src points to at least 6 bytes Postcondition: ethhdr initialized, in host byte order

void rst_initICMP (  struct icmphdr *  icmphdr, unsigned char  type )

Initialize an ICMP header. Parameters: icmphdr  address of header to be initialized type  ICMP type Precondition: icmphdr points to at least RST_ICMP_HDR_LEN bytes Postcondition: icmphdr initialized, in host byte order

void rst_initIP (  struct iphdr *  iphdr, unsigned short  totalLen, unsigned char  protocol, unsigned int  srcAddr, unsigned int  dstAddr )

Initialize an IP header. Parameters: iphdr  address of header to be initialized totalLen  total IP packet length in bytes protocol  next layer protocol srcAddr  IP source address dstAddr  IP destination address Precondition: iphdr points to at least RST_IP_HDR_LEN bytes Postcondition: iphdr initialized, in host byte order

void rst_initRbuf (  struct rst_buf *  rBuf, unsigned char *  buf, int  bufLen, unsigned int  mask )

Initialize an rst_buf. Parameters: rBuf  rst_buf to be initialized buf  frame byte array bufLen  length of buf mask  specification of active header pointers Postcondition: rBuf.buf == buf rBuf.bufLen == bufLen the masked rBuf pointers point to the appropriate locations in buf; the unmasked pointers are null

void rst_initTCP (  struct tcphdr *  tcphdr, unsigned short  srcPort, unsigned short  dstPort )

Initialize a TCP header. Parameters: tcphdr  address of header to be initialized srcPort  source port dstPort  destination port Precondition: tcphdr points to at least RST_TCP_HDR_LEN bytes Postcondition: tcphdr initialized, in host byte order

void rst_initUDP (  struct udphdr *  udphdr, unsigned short  srcPort, unsigned short  dstPort, unsigned short  len )

Initialize a UDP header. Parameters: udphdr  address of header to be initialized srcPort  source port dstPort  destination port len  total UDP length in bytes Precondition: udphdr points to at least RST_UDP_HDR_LEN bytes Postcondition: udphdr initialized, in host byte order

unsigned char* rst_ipData (  struct rst_buf *   )

Get the address of the IP header in rBuf.

void rst_ntohp (  struct rst_buf *  rBuf  )

Parse an incoming packet and do network-to-host byte swapping. Parameters: rBuf  an rst_buf containing the packet to be parsed in rBuf.buf[0..rBuf.bufLen-1] Precondition: rBuf.buf[0..rBuf.bufLen-1] is allocated and "legal" Postcondition: for each non-null pointer p in rBuf, appropriate byte swapping and checksum calculation has been done.

unsigned char* rst_tcpData (  struct rst_buf *   )

Get the address of the TCP header in rBuf.

unsigned char* rst_udpData (  struct rst_buf *   )

Get the address of the UDP header in rBuf.

int rst_verifyRbuf (  struct rst_buf *  rBuf  )

Check that an rst_buf is safe, in the sense that a call to rst_htonp will not abort. Three kinds of checks are made: The non-null header pointers are one of: Ethernet Ethernet and ARP Ethernet and IP Ethernet, IP and ICMP Ethernet, IP and TCP Ethernet, IP and UDP For the non-null header pointers, the headers start at buf[0], are contiguous and non-overlapping, and are completely contained in buf. The data indicated by the dynamic length fields, where present, are completely contained in buf. Parameters: rBuf  an rst_buf Precondition: rBuf.buf[0..rBuf.bufLen-1] is allocated rBuf.bufLen >= 0 no IP or TCP options are present Returns: 0 if rBuf is safe; non-zero otherwise

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