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#include <stdio.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <string.h>
#include "tsg_entry.h"
#include <MESA/MESA_handle_logger.h>
#include "tsg_protocol_common.h"
#define IPV4_TYPE 1 //ADDR_TYPE_IPV4 ==1 , 取的enum 0x0800
#define IPV6_TYPE 2 //ADDR_TYPE_IPV6 ==2 0x86dd
#define TCP_TYPE 0x06
#define UDP_TYPE 0x11
#define ICMP_PROTOCOL_TYPE 0x01 //ipv4 icmp proctocol
#define ICMPV6_PROTOCAL_TYPE 0x3a //ipv6 icmpv6 protocl
#define ICMPV4_UNREACHABLE 0x03
#define ICMPV4_PORT_UNREACHABLE 0x03
#define ICMPV4_ADMINISTRATIVELY_PROHIBITED 0x0d
#define ICMPV6_UNREACHABLE 0x01
#define ICMPV6_PORT_UNREACHABLE 0X04
#define ICMPV6_ADMINISTRATIVELY_PROHIBITED 0x01
//icmp
#define ICMP_HEADR_BYTE_LEN 8
#define ICMP_MAX_LEN 2048
#define ETHERNET_BYTE_LEN 14
//icmpv4
#define IPV4_HEADR_BYTE_LEN 20
#define IPV4_IPADDR_BYTE_LEN 4
#define IPV4_TOTAL_LEN_INDEX 2
#define IPV4_TOTAL_BYTE_LEN 2
#define IPV4_SIP_INDEX 12
#define IPV4_DIP_INDEX 16
#define IPV4_PROTOCOL_INDEX 9
#define IPV4_CHECKSUM_INDEX 10
#define IPV4_CHECKSUM_BYTE_LEN 2
#define ICMPV4_SRCPACKET_MAX_LEN 548 // 548 == ipv4(max_len 576)-ip_len(20)-icmp_head_len(8)
//icmpv6
//#define ICMPV6_ICMP_INDEX 40
#define IPV6_HEADR_BYTE_LEN 40
#define IPV6_IPADDR_BYTE_LEN 16
#define IPV6_PAYLOAD_BYTE_LEN 2
#define IPV6_SIP_INDEX 8
#define IPV6_DIP_INDEX 24
#define IPV6_PAYLOAD_INDEX 4
#define IPV6_NEXT_HEADR_INDEX 6
#define IPV6_2IP_BYTE_LEN 32
#define IPV6_PESUDO_HEADR_BYTE_LEN 40
#define IPV6_PESUDO_UPPER_LAYER_PACKET_AND_ZERO_LEN 7
#define IPV6_PESUDO_HEAD_PAYLOAD_BYTE_LEN 4
#define ICMPV6_SRCPACKET_MTU 1232 // 1232 == ipv6(max_len 1280)-ipv6_headr_len(40)-icmp_head_len(8)
#define ICMPV6_MTU 1280 // ICMPV6_SRCPACKET_MTU + IPV6_HEADR_BYTE_LEN + ICMPV6_HEARD_LEN
typedef struct icmp_st_{
char type;
char code;
short checksum;
char un_user[4];
char origin_data[ICMPV6_SRCPACKET_MTU];
}icmp_st;
static short in_checksum(void *pkg, int size)
{
int nleft = size;
int sum = 0;
unsigned short *w = (unsigned short *)pkg;
unsigned short answer = 0;
while (nleft > 1)
{
sum += *w++;
nleft -= 2;
}
if (nleft == 1)
{
* (unsigned char *) (&answer) = *(unsigned char *)w;
sum += answer;
}
while (sum >> 16){
sum = (sum & 0xFFFF) + (sum >> 16);
}
answer = ~sum &0xffff;
return answer;
}
static void four_byte_alignment(unsigned short *icmp_len, unsigned short *icmp_checksum_len){
short temp = 0;
temp = *icmp_len % 4;
if(temp >0){
*icmp_len = *icmp_len+(4-temp);
*icmp_checksum_len = *icmp_checksum_len+(4-temp);
}
return ;
}
/*
* ICMP 报文格式
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type | Code | Checksum |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | unused |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Internet Header + 64 bits of Original Data Datagram |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* ICMPV4 = [ipv4_headr]+[icmp]
* ICMPV4(MTU) 576
*/
static void format_icmpv4(const char *raw_pkt, char *ret_icmpv4, int *ret_len){
icmp_st icmp = {0};
char ipv4_headr[IPV4_HEADR_BYTE_LEN] = {0};
unsigned short raw_ipv4_total_len = 0;
unsigned short icmpv4_len = 0;
unsigned short ipv4_total_len = 0;
unsigned short ipv4_checksum = 0;
unsigned short icmp_len = 0;
unsigned short icmp_original_data_len = 0;
unsigned short icmp_start_len = IPV4_HEADR_BYTE_LEN;
memcpy(&raw_ipv4_total_len, &raw_pkt[IPV4_TOTAL_LEN_INDEX], IPV4_TOTAL_BYTE_LEN);
raw_ipv4_total_len = htons(raw_ipv4_total_len);
//src_packet_len = raw_ipv4_total_len + ETH_LEN;
if(raw_ipv4_total_len >= ICMPV4_SRCPACKET_MAX_LEN){
icmp_original_data_len = ICMPV4_SRCPACKET_MAX_LEN;
}else{
icmp_original_data_len = raw_ipv4_total_len;
}
icmp_len = icmp_original_data_len + ICMP_HEADR_BYTE_LEN;
ipv4_total_len = icmp_len + IPV4_HEADR_BYTE_LEN;
icmpv4_len = ipv4_total_len;
//format ipv4 headr
memcpy(ipv4_headr, raw_pkt, IPV4_HEADR_BYTE_LEN); //copy source data
memcpy(&ipv4_headr[IPV4_SIP_INDEX], &raw_pkt[IPV4_DIP_INDEX], IPV4_IPADDR_BYTE_LEN); //format ipv4 sip
memcpy(&ipv4_headr[IPV4_DIP_INDEX], &raw_pkt[IPV4_SIP_INDEX], IPV4_IPADDR_BYTE_LEN); //format ipv4 dip
ipv4_headr[IPV4_PROTOCOL_INDEX] = ICMP_PROTOCOL_TYPE; //set ipv4 protocol type (0x01 == ICMP)
ipv4_total_len = htons(ipv4_total_len);
memcpy(&ipv4_headr[IPV4_TOTAL_LEN_INDEX], &ipv4_total_len, IPV4_TOTAL_BYTE_LEN); //format ipv4 total len
memset(&ipv4_headr[IPV4_CHECKSUM_INDEX], 0, IPV4_CHECKSUM_BYTE_LEN); //empty checksum data
ipv4_checksum = in_checksum(ipv4_headr, IPV4_HEADR_BYTE_LEN); //calc ipv4 checksum
memcpy(&ipv4_headr[IPV4_CHECKSUM_INDEX], &ipv4_checksum, IPV4_CHECKSUM_BYTE_LEN); //format ipv4 checksum
//format icmp
memset(&icmp, 0, sizeof(icmp_st));
memcpy(icmp.origin_data, raw_pkt, icmp_original_data_len);
icmp.type = ICMPV4_UNREACHABLE;
icmp.code = ICMPV4_ADMINISTRATIVELY_PROHIBITED;
icmp.checksum = in_checksum((void*)&icmp, icmp_len);
//format complete icmpv4 packet
memcpy(ret_icmpv4, ipv4_headr, IPV4_HEADR_BYTE_LEN);
memcpy(&ret_icmpv4[icmp_start_len], &icmp, icmp_len);
*ret_len = icmpv4_len;
return;
}
/*
* icmpv6数据包组�? * [ICMPV6] = [ipv6_headr]+[icmp]
*
* icmpv6的最大MTU应是ipv6的最小MTU(1280)
* <本端内容来自RFC443>
* Every ICMPv6 error message (type < 128) MUST include as much of
* the IPv6 offending (invoking) packet (the packet that caused the
* error) as possible without making the error message packet exceed
* the minimum IPv6 MTU [IPv6].
*
* [ICMPV6] = [ipv6_headr]+[icmp]
*
* 计算ICMPV6的校验和�?(ICMP + 伪首�? 作为计算数据部分
* 注意�?ICMPV6数据要补充成四字节对�? * ipv6伪首部数�? 长度
* {
* Soucre Address : 16
* Destination Address: 16
* Upper-Layer Packet Length: 4
* zero: 3
* Next Heard: 1
* }
*
** +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* + +
* ~ ~
* ~ icmp ~
* | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* + +
* | |
* + Source Address +
* | |
* + +
* | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* + +
* | |
* + Destination Address +
* | |
* + +
* | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Upper-Layer Packet Length |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | zero | Next Header |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* [ICMPV6] = [ipv6_headr]+[icmp]
* ICMPV6(MTU) 1280
*/
static void format_icmpv6(const char *raw_pkt, char *ret_icmpv6, int *ret_len){
icmp_st icmp = {0};
char icmp_checksum_buf[ICMPV6_MTU] = {0};
char ipv6_headr[IPV6_HEADR_BYTE_LEN] = {0};
unsigned short ipv6_payload_len = 0;
unsigned short raw_ipv6_payload_len = 0;
unsigned short raw_pkt_len = 0;
unsigned short icmpv6_len = 0;
unsigned short icmp_len = 0;
unsigned short icmp_original_data_len = 0;
unsigned short icmp_checksum_len = 0;
unsigned int upper_layer_packet_len = 0;
memcpy(&raw_ipv6_payload_len, &raw_pkt[IPV6_PAYLOAD_INDEX], IPV6_PAYLOAD_BYTE_LEN); //get ipv6_payload_len
raw_pkt_len = ntohs(raw_ipv6_payload_len) + IPV6_HEADR_BYTE_LEN;
if(raw_pkt_len >= ICMPV6_SRCPACKET_MTU){
icmp_original_data_len = ICMPV6_SRCPACKET_MTU;
}else{
icmp_original_data_len = raw_pkt_len;
}
icmp_len = icmp_original_data_len + ICMP_HEADR_BYTE_LEN;
icmpv6_len = IPV6_HEADR_BYTE_LEN + icmp_len;
icmp_checksum_len = icmp_len + IPV6_PESUDO_HEADR_BYTE_LEN;
ipv6_payload_len = htons(icmp_len);
//format ipv6 headr
memcpy(ipv6_headr, raw_pkt, IPV6_HEADR_BYTE_LEN); //format source ipv6 data
memcpy(&ipv6_headr[IPV6_SIP_INDEX], &raw_pkt[IPV6_DIP_INDEX], IPV6_IPADDR_BYTE_LEN); //modify format sip
memcpy(&ipv6_headr[IPV6_DIP_INDEX], &raw_pkt[IPV6_SIP_INDEX], IPV6_IPADDR_BYTE_LEN); //modify format dip
memcpy(&ipv6_headr[IPV6_PAYLOAD_INDEX], &ipv6_payload_len, IPV6_PAYLOAD_BYTE_LEN); //modify format ipv6 payload
ipv6_headr[IPV6_NEXT_HEADR_INDEX] = ICMPV6_PROTOCAL_TYPE; //modify format ipv6 protocol (icmpv6 == 0X3a);
//format icmp
memset(&icmp, 0, sizeof(icmp_st));
icmp.type = ICMPV6_UNREACHABLE;
icmp.code = ICMPV6_ADMINISTRATIVELY_PROHIBITED;
memcpy(icmp.origin_data, raw_pkt, icmp_original_data_len);
upper_layer_packet_len = htonl((int)icmp_len);
four_byte_alignment(&icmp_len, &icmp_checksum_len); //icmp_len和icmp_checksum_len 补充�?字节对齐
//calc icmp checksum
memcpy(icmp_checksum_buf, &icmp, icmp_len);
memcpy(&icmp_checksum_buf[icmp_len], &ipv6_headr[IPV6_SIP_INDEX], IPV6_2IP_BYTE_LEN);
memcpy(&icmp_checksum_buf[icmp_len+IPV6_2IP_BYTE_LEN], &upper_layer_packet_len, IPV6_PESUDO_HEAD_PAYLOAD_BYTE_LEN);
icmp_checksum_buf[icmp_len+IPV6_2IP_BYTE_LEN+IPV6_PESUDO_UPPER_LAYER_PACKET_AND_ZERO_LEN] = ICMPV6_PROTOCAL_TYPE;
icmp.checksum = in_checksum(icmp_checksum_buf, icmp_checksum_len);
//format complete icmpv6 packet
memcpy(ret_icmpv6, ipv6_headr, IPV6_HEADR_BYTE_LEN);
memcpy(&ret_icmpv6[IPV6_HEADR_BYTE_LEN], &icmp, icmp_len);
*ret_len = icmpv6_len;
return;
}
static void format_icmp(const char *raw_pkt, char *icmp_buf, int *icmp_len, int ip_type){
if(IPV4_TYPE == ip_type) {
format_icmpv4(raw_pkt, icmp_buf, icmp_len);
} else{ //IPV6_TYPE
format_icmpv6(raw_pkt, icmp_buf, icmp_len);
}
return;
}
unsigned char send_icmp_unreachable(const struct streaminfo *a_stream)
{
int opt_value=1;
void *raw_pkt=NULL;
int ret=get_rawpkt_opt_from_streaminfo(a_stream, RAW_PKT_GET_DATA, &raw_pkt);
if(ret<0 || (1==ret && NULL!=raw_pkt))
{
MESA_set_stream_opt(a_stream, MSO_DROP_CURRENT_PKT, (void *)&opt_value, sizeof(opt_value));
return STATE_GIVEME;
}
if(NULL!=raw_pkt)
{
int icmp_len=0;
char icmp_buf[ICMP_MAX_LEN]={0};
format_icmp((char *)raw_pkt+ETHERNET_BYTE_LEN, icmp_buf, &icmp_len, a_stream->addr.addrtype);
tsg_send_inject_packet(a_stream, SIO_EXCLUDE_THIS_LAYER_HDR, icmp_buf, icmp_len, MESA_dir_reverse(a_stream->routedir));
MESA_set_stream_opt(a_stream, MSO_DROP_CURRENT_PKT, (void *)&opt_value, sizeof(opt_value));
}
return STATE_GIVEME;
}
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