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/*
// Copyright (c) 2010-2017 Intel Corporation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
*/
#include <pcap.h>
#include <inttypes.h>
#include <cstring>
#include <arpa/inet.h>
#include <iostream>
#include <fstream>
#include <cstdlib>
#include "allocator.hpp"
#include "pcappkt.hpp"
Allocator *PcapPkt::allocator = NULL;
void* PcapPkt::operator new(size_t size)
{
if (allocator)
return allocator->alloc(size);
else
return ::operator new(size);
}
void PcapPkt::operator delete(void *pointer)
{
if (!allocator)
:: operator delete(pointer);
}
PcapPkt::PcapPkt(uint8_t *mem)
{
header = *(struct pcap_pkthdr *)mem;
mem += sizeof(header);
buf = new uint8_t[header.len];
memcpy(buf, mem, header.len);
}
PcapPkt::PcapPkt()
{
buf = new uint8_t[1514];
memset(&header, 0, sizeof(header));
}
PcapPkt::PcapPkt(const PcapPkt& other)
{
if (!allocator) {
buf = new uint8_t[other.len()];
}
else {
buf = (uint8_t *)allocator->alloc(other.len());
}
memcpy(buf, other.buf, other.len());
header = other.header;
}
PcapPkt::~PcapPkt()
{
if (!allocator)
delete[] buf;
}
#define ETYPE_IPv4 0x0008 /* IPv4 in little endian */
#define ETYPE_IPv6 0xDD86 /* IPv6 in little endian */
#define ETYPE_ARP 0x0608 /* ARP in little endian */
#define ETYPE_VLAN 0x0081 /* 802-1aq - VLAN */
#define ETYPE_MPLSU 0x4788 /* MPLS unicast */
#define ETYPE_MPLSM 0x4888 /* MPLS multicast */
#define ETYPE_8021ad 0xA888 /* Q-in-Q */
#define ETYPE_LLDP 0xCC88 /* Link Layer Discovery Protocol (LLDP) */
#define ETYPE_EoGRE 0x5865 /* EoGRE in little endian */
struct ipv4_hdr {
uint8_t version_ihl; /**< version and header length */
uint8_t type_of_service; /**< type of service */
uint16_t total_length; /**< length of packet */
uint16_t packet_id; /**< packet ID */
uint16_t fragment_offset; /**< fragmentation offset */
uint8_t time_to_live; /**< time to live */
uint8_t next_proto_id; /**< protocol ID */
uint16_t hdr_checksum; /**< header checksum */
uint32_t src_addr; /**< source address */
uint32_t dst_addr; /**< destination address */
} __attribute__((__packed__));
struct ether_addr {
uint8_t addr_bytes[6]; /**< Address bytes in transmission order */
} __attribute__((__packed__));
struct ether_hdr {
struct ether_addr d_addr; /**< Destination address. */
struct ether_addr s_addr; /**< Source address. */
uint16_t ether_type; /**< Frame type. */
} __attribute__((__packed__));
struct vlan_hdr {
uint16_t vlan_tci; /**< Priority (3) + CFI (1) + Identifier Code (12) */
uint16_t eth_proto;/**< Ethernet type of encapsulated frame. */
} __attribute__((__packed__));
struct udp_hdr {
uint16_t src_port; /**< UDP source port. */
uint16_t dst_port; /**< UDP destination port. */
uint16_t dgram_len; /**< UDP datagram length */
uint16_t dgram_cksum; /**< UDP datagram checksum */
} __attribute__((__packed__));
struct pkt_tuple PcapPkt::parsePkt(const uint8_t **l4_hdr, uint16_t *hdr_len, const uint8_t **l5, uint32_t *l5_len) const
{
struct pkt_tuple pt = {0};
const struct ether_hdr *peth = (struct ether_hdr *)buf;
int l2_types_count = 0;
const struct ipv4_hdr* pip = 0;
switch (peth->ether_type) {
case ETYPE_IPv4:
pip = (const struct ipv4_hdr *)(peth + 1);
break;
case ETYPE_VLAN: {
const struct vlan_hdr *vlan = (const struct vlan_hdr *)(peth + 1);
if (vlan->eth_proto == ETYPE_IPv4) {
pip = (const struct ipv4_hdr *)(peth + 1);
}
else if (vlan->eth_proto == ETYPE_VLAN) {
const struct vlan_hdr *vlan = (const struct vlan_hdr *)(peth + 1);
if (vlan->eth_proto == ETYPE_IPv4) {
pip = (const struct ipv4_hdr *)(peth + 1);
}
else if (vlan->eth_proto == ETYPE_IPv6) {
throw 0;
}
else {
/* TODO: handle BAD PACKET */
throw 0;
}
}
}
break;
case ETYPE_8021ad: {
const struct vlan_hdr *vlan = (const struct vlan_hdr *)(peth + 1);
if (vlan->eth_proto == ETYPE_VLAN) {
const struct vlan_hdr *vlan = (const struct vlan_hdr *)(peth + 1);
if (vlan->eth_proto == ETYPE_IPv4) {
pip = (const struct ipv4_hdr *)(peth + 1);
}
else {
throw 0;
}
}
else {
throw 0;
}
}
break;
case ETYPE_MPLSU:
break;
default:
break;
}
/* L3 */
if ((pip->version_ihl >> 4) == 4) {
if ((pip->version_ihl & 0x0f) != 0x05) {
/* TODO: optional fields */
throw 0;
}
pt.proto_id = pip->next_proto_id;
pt.src_addr = pip->src_addr;
pt.dst_addr = pip->dst_addr;
}
else {
/* TODO: IPv6 and bad packets */
throw 0;
}
/* L4 parser */
if (pt.proto_id == IPPROTO_UDP) {
const struct udp_hdr *udp = (const struct udp_hdr*)(pip + 1);
if (l4_hdr)
*l4_hdr = (const uint8_t*)udp;
if (hdr_len)
*hdr_len = (const uint8_t*)udp - buf;
pt.src_port = udp->src_port;
pt.dst_port = udp->dst_port;
if (l5)
*l5 = ((const uint8_t*)udp) + sizeof(struct udp_hdr);
if (l5_len)
*l5_len = ntohs(udp->dgram_len) - sizeof(struct udp_hdr);
}
else if (pt.proto_id == IPPROTO_TCP) {
const struct tcp_hdr *tcp = (const struct tcp_hdr *)(pip + 1);
if (l4_hdr)
*l4_hdr = (const uint8_t*)tcp;
if (hdr_len)
*hdr_len = (const uint8_t*)tcp - buf;
pt.src_port = tcp->src_port;
pt.dst_port = tcp->dst_port;
if (l5)
*l5 = ((const uint8_t*)tcp) + ((tcp->data_off >> 4)*4);
if (l5_len)
*l5_len = ntohs(pip->total_length) - sizeof(struct ipv4_hdr) - ((tcp->data_off >> 4)*4);
}
else {
fprintf(stderr, "unsupported protocol %d\n", pt.proto_id);
throw 0;
}
return pt;
}
void PcapPkt::toMem(uint8_t *mem) const
{
memcpy(mem, &header, sizeof(header));
mem += sizeof(header);
memcpy(mem, buf, header.len);
}
void PcapPkt::fromMem(uint8_t *mem)
{
memcpy(&header, mem, sizeof(header));
mem += sizeof(header);
memcpy(buf, mem, header.len);
}
void PcapPkt::toFile(ofstream *file) const
{
file->write(reinterpret_cast<const char *>(&header), sizeof(header));
file->write(reinterpret_cast<const char *>(buf), header.len);
}
size_t PcapPkt::memSize() const
{
return sizeof(header) + header.len;
}
PcapPkt::L4Proto PcapPkt::getProto() const
{
struct pkt_tuple pt = parsePkt();
return pt.proto_id == IPPROTO_TCP? PROTO_TCP : PROTO_UDP;
}
ostream& operator<<(ostream& stream, const pkt_tuple &other)
{
stream << other.src_addr << ","
<< other.dst_addr << ","
<< (int)other.proto_id << ","
<< other.src_port << ","
<< other.dst_port;
return stream;
}
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