Adding missing files.

This commit is contained in:
Robin Sommer 2015-07-20 16:49:03 -07:00
parent fcf8cef949
commit f69edd1437
4 changed files with 556 additions and 0 deletions

117
src/iosource/Layer2.cc Normal file
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// See the file "COPYING" in the main distribution directory for copyright.
#include "IP.h"
#include "Type.h"
#include "Val.h"
#include "Var.h"
#include "NetVar.h"
#include "iosource/Layer2.h"
#include "iosource/Packet.h"
extern "C" {
#include <pcap.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <net/if.h>
#include <net/if_arp.h>
#ifdef HAVE_NET_ETHERNET_H
#include <net/ethernet.h>
#elif defined(HAVE_SYS_ETHERNET_H)
#include <sys/ethernet.h>
#elif defined(HAVE_NETINET_IF_ETHER_H)
#include <netinet/if_ether.h>
#elif defined(HAVE_NET_ETHERTYPES_H)
#include <net/ethertypes.h>
#endif
}
Val *L2_Hdr::fmt_eui48(const u_char *mac) const
{
char buf[20];
snprintf(buf, sizeof buf, "%02x:%02x:%02x:%02x:%02x:%02x",
mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
return new StringVal(buf);
}
RecordVal* L2_Hdr::BuildPktHdrVal() const
{
static RecordType* l2_hdr_type = 0;
static RecordType* raw_pkt_hdr_type = 0;
if ( ! raw_pkt_hdr_type )
{
raw_pkt_hdr_type = internal_type("raw_pkt_hdr")->AsRecordType();
l2_hdr_type = internal_type("l2_hdr")->AsRecordType();
}
RecordVal* pkt_hdr = new RecordVal(raw_pkt_hdr_type);
RecordVal* l2_hdr = new RecordVal(l2_hdr_type);
int is_ethernet = (pkt->link_type == DLT_EN10MB) ? 1 : 0;
int l3 = BifEnum::L3_UNKNOWN;
if ( pkt->l3_proto == L3_IPV4 )
l3 = BifEnum::L3_IPV4;
else if ( pkt->l3_proto == L3_IPV6 )
l3 = BifEnum::L3_IPV6;
else if ( pkt->l3_proto == L3_ARP )
l3 = BifEnum::L3_ARP;
// l2_hdr layout:
// encap: link_encap; ##< L2 link encapsulation
// len: count; ##< Total frame length on wire
// cap_len: count; ##< Captured length
// src: string &optional; ##< L2 source (if ethernet)
// dst: string &optional; ##< L2 destination (if ethernet)
// vlan: count &optional; ##< VLAN tag if any (and ethernet)
// ethertype: count &optional; ##< If ethernet
// proto: layer3_proto; ##< L3 proto
if ( is_ethernet )
{
// Ethernet header layout is:
// dst[6bytes] src[6bytes] ethertype[2bytes]...
l2_hdr->Assign(0, new EnumVal(BifEnum::LINK_ETHERNET, BifType::Enum::link_encap));
l2_hdr->Assign(3, fmt_eui48(pkt->data + 6)); // src
l2_hdr->Assign(4, fmt_eui48(pkt->data)); // dst
if ( pkt->vlan )
l2_hdr->Assign(5, new Val(pkt->vlan, TYPE_COUNT));
l2_hdr->Assign(6, new Val(pkt->eth_type, TYPE_COUNT));
if ( pkt->eth_type == ETHERTYPE_ARP || pkt->eth_type == ETHERTYPE_REVARP )
// We also identify ARP for L3 over ethernet
l3 = BifEnum::L3_ARP;
}
else
l2_hdr->Assign(0, new EnumVal(BifEnum::LINK_UNKNOWN, BifType::Enum::link_encap));
l2_hdr->Assign(1, new Val(pkt->len, TYPE_COUNT));
l2_hdr->Assign(2, new Val(pkt->cap_len, TYPE_COUNT));
l2_hdr->Assign(7, new EnumVal(l3, BifType::Enum::layer3_proto));
pkt_hdr->Assign(0, l2_hdr);
if ( pkt->l3_proto == L3_IPV4 )
{
IP_Hdr ip_hdr((const struct ip*)(pkt->data + pkt->hdr_size), false);
return ip_hdr.BuildPktHdrVal(pkt_hdr, 1);
}
else if ( pkt->l3_proto == L3_IPV6 )
{
IP_Hdr ip6_hdr((const struct ip6_hdr*)(pkt->data + pkt->hdr_size), false, pkt->cap_len);
return ip6_hdr.BuildPktHdrVal(pkt_hdr, 1);
}
else
return pkt_hdr;
}

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src/iosource/Layer2.h Normal file
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#ifndef l2_h
#define l2_h
#include "config.h"
#include "net_util.h"
#include "IP.h"
#include "Reporter.h"
#include "Val.h"
#include "Type.h"
#include <vector>
class Packet;
/**
* A class that wraps an L2 packet.
*/
class L2_Hdr {
public:
L2_Hdr(const Packet *arg_pkt) : pkt(arg_pkt) { }
~L2_Hdr() { }
/**
* Returns a raw_pkt_hdr RecordVal, which includes L2 and also
* everything in IP_Hdr (i.e. IP4/6 + tcp/udp/icmp)
*/
RecordVal* BuildPktHdrVal() const;
private:
Val *fmt_eui48(const u_char *mac) const;
const Packet *pkt;
};
#endif

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src/iosource/Packet.cc Normal file
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#include "Packet.h"
#include "Sessions.h"
void Packet::Weird(const char* name)
{
sessions->Weird(name, this);
l2_valid = false;
}
int Packet::GetLinkHeaderSize(int link_type)
{
switch ( link_type ) {
case DLT_NULL:
return 4;
case DLT_EN10MB:
return 14;
case DLT_FDDI:
return 13 + 8; // fddi_header + LLC
#ifdef DLT_LINUX_SLL
case DLT_LINUX_SLL:
return 16;
#endif
case DLT_PPP_SERIAL: // PPP_SERIAL
return 4;
case DLT_RAW:
return 0;
}
return -1;
}
void Packet::ProcessLayer2()
{
l2_valid = true;
// Unfortunately some packets on the link might have MPLS labels
// while others don't. That means we need to ask the link-layer if
// labels are in place.
bool have_mpls = false;
const u_char* pdata = data;
switch ( link_type ) {
case DLT_NULL:
{
int protocol = (pdata[3] << 24) + (pdata[2] << 16) + (pdata[1] << 8) + pdata[0];
pdata += GetLinkHeaderSize(link_type);
// From the Wireshark Wiki: "AF_INET6, unfortunately, has
// different values in {NetBSD,OpenBSD,BSD/OS},
// {FreeBSD,DragonFlyBSD}, and {Darwin/Mac OS X}, so an IPv6
// packet might have a link-layer header with 24, 28, or 30
// as the AF_ value." As we may be reading traces captured on
// platforms other than what we're running on, we accept them
// all here.
if ( protocol == AF_INET )
l3_proto = L3_IPV4;
else if ( protocol == 24 || protocol == 28 || protocol == 30 )
l3_proto = L3_IPV6;
else
{
Weird("non_ip_packet_in_null_transport");
return;
}
break;
}
case DLT_EN10MB:
{
// Get protocol being carried from the ethernet frame.
int protocol = (pdata[12] << 8) + pdata[13];
pdata += GetLinkHeaderSize(link_type);
eth_type = protocol;
switch ( protocol )
{
// MPLS carried over the ethernet frame.
case 0x8847:
have_mpls = true;
break;
// VLAN carried over the ethernet frame.
// 802.1q / 802.1ad
case 0x8100:
case 0x9100:
vlan = ((pdata[0] << 8) + pdata[1]) & 0xfff;
protocol = ((pdata[2] << 8) + pdata[3]);
pdata += 4; // Skip the vlan header
// Check for MPLS in VLAN.
if ( protocol == 0x8847 )
{
have_mpls = true;
break;
}
// Check for double-tagged (802.1ad)
if ( protocol == 0x8100 || protocol == 0x9100 )
{
protocol = ((pdata[2] << 8) + pdata[3]);
pdata += 4; // Skip the vlan header
}
eth_type = protocol;
break;
// PPPoE carried over the ethernet frame.
case 0x8864:
protocol = (pdata[6] << 8) + pdata[7];
pdata += 8; // Skip the PPPoE session and PPP header
if ( protocol == 0x0021 )
l3_proto = L3_IPV4;
else if ( protocol == 0x0057 )
l3_proto = L3_IPV6;
else
{
// Neither IPv4 nor IPv6.
Weird("non_ip_packet_in_pppoe_encapsulation");
return;
}
break;
}
// Normal path to determine Layer 3 protocol.
if ( ! have_mpls && l3_proto == L3_UNKNOWN )
{
if ( protocol == 0x800 )
l3_proto = L3_IPV4;
else if ( protocol == 0x86dd )
l3_proto = L3_IPV6;
else if ( protocol == 0x0806 || protocol == 0x8035 )
l3_proto = L3_ARP;
else
{
// Neither IPv4 nor IPv6.
Weird("non_ip_packet_in_ethernet");
return;
}
}
break;
}
case DLT_PPP_SERIAL:
{
// Get PPP protocol.
int protocol = (pdata[2] << 8) + pdata[3];
pdata += GetLinkHeaderSize(link_type);
if ( protocol == 0x0281 )
{
// MPLS Unicast. Remove the pdata link layer and
// denote a header size of zero before the IP header.
have_mpls = true;
}
else if ( protocol == 0x0021 )
l3_proto = L3_IPV4;
else if ( protocol == 0x0057 )
l3_proto = L3_IPV6;
else
{
// Neither IPv4 nor IPv6.
Weird("non_ip_packet_in_ppp_encapsulation");
return;
}
break;
}
default:
{
// Assume we're pointing at IP. Just figure out which version.
pdata += GetLinkHeaderSize(link_type);
const struct ip* ip = (const struct ip *)pdata;
if ( ip->ip_v == 4 )
l3_proto = L3_IPV4;
else if ( ip->ip_v == 6 )
l3_proto = L3_IPV6;
else
{
// Neither IPv4 nor IPv6.
Weird("non_ip_packet");
return;
}
break;
}
}
if ( have_mpls )
{
// Skip the MPLS label stack.
bool end_of_stack = false;
while ( ! end_of_stack )
{
end_of_stack = *(pdata + 2) & 0x01;
pdata += 4;
if ( pdata >= pdata + cap_len )
{
Weird("no_mpls_payload");
return;
}
}
// We assume that what remains is IP
if ( pdata + sizeof(struct ip) >= data + cap_len )
{
Weird("no_ip_in_mpls_payload");
return;
}
const struct ip* ip = (const struct ip *)pdata;
if ( ip->ip_v == 4 )
l3_proto = L3_IPV4;
else if ( ip->ip_v == 6 )
l3_proto = L3_IPV6;
else
{
// Neither IPv4 nor IPv6.
Weird("no_ip_in_mpls_payload");
return;
}
}
else if ( encap_hdr_size )
{
// Blanket encapsulation. We assume that what remains is IP.
pdata += encap_hdr_size;
if ( pdata + sizeof(struct ip) >= data + cap_len )
{
Weird("no_ip_left_after_encap");
return;
}
const struct ip* ip = (const struct ip *)pdata;
if ( ip->ip_v == 4 )
l3_proto = L3_IPV4;
else if ( ip->ip_v == 6 )
l3_proto = L3_IPV6;
else
{
// Neither IPv4 nor IPv6.
Weird("no_ip_in_encap");
return;
}
}
// We've now determined (a) L3_IPV4 vs (b) L3_IPV6 vs
// (c) L3_ARP vs (d) L3_UNKNOWN (0 == anything else)
l3_proto = l3_proto;
// Calculate how much header we've used up.
hdr_size = (pdata - data);
}

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#ifndef packet_h
#define packet_h
#include "Desc.h"
#include "IP.h"
#include "NetVar.h"
enum Layer3Proto {
L3_UNKNOWN = -1,
L3_IPV4 = 1,
L3_IPV6 = 2,
L3_ARP = 3,
};
// A link-layer packet.
//
// Note that for serialization we don't use much of the support provided by
// the serialization framework. Serialize/Unserialize do all the work by
// themselves. In particular, Packets aren't derived from SerialObj. They are
// completely seperate and self-contained entities, and we don't need any of
// the sophisticated features like object caching.
class Packet {
public:
Packet()
{
struct timeval ts = {0, 0};
Init(0, &ts, 0, 0, 0);
}
// Construct and initialize from packet data.
//
// arg_free: If true makes an internal copy of the *data*. If false,
// stores just a pointer to *data*, which must remain valid.
Packet(int arg_link_type, struct timeval *arg_ts, uint32 arg_caplen,
uint32 arg_len, const u_char *arg_data, int arg_free = false,
std::string arg_tag = std::string(""))
{
Init(arg_link_type, arg_ts, arg_caplen, arg_len, arg_data, arg_free, arg_tag);
}
~Packet()
{
if ( free )
delete [] data;
}
// Initialize with data from pointer.
//
// arg_free: If true makes an internal copy of the *data*. If false,
// stores just a pointer to *data*, which must remain valid.
void Init(int arg_link_type, struct timeval *arg_ts, uint32 arg_caplen,
uint32 arg_len, const u_char *arg_data, int arg_free = false,
std::string arg_tag = std::string(""), uint32 arg_hdrsize = 0)
{
link_type = arg_link_type;
ts = *arg_ts;
cap_len = arg_caplen;
len = arg_len;
free = arg_free;
if ( free )
{
data = new u_char[cap_len];
memcpy(const_cast<u_char *>(data), arg_data, cap_len);
}
else
data = arg_data;
hdr_size = arg_hdrsize;
l3_proto = L3_UNKNOWN;
tag = arg_tag;
time = ts.tv_sec + double(ts.tv_usec) / 1e6;
eth_type = 0;
vlan = 0;
l2_valid = false;
if ( data )
ProcessLayer2();
}
const IP_Hdr IP() const
{ return IP_Hdr((struct ip *) (data + hdr_size), false); }
// Returns true if parsing the Layer 2 fields failed, including when
// no data was passed into the constructor in the first place.
bool Layer2Valid()
{
return l2_valid;
}
void Describe(ODesc* d) const;
/**
* Helper method to return the header size for a given link tyoe.
*
* @param link_type The link tyoe.
*
* @return The header size in bytes, or -1 if not known.
*/
static int GetLinkHeaderSize(int link_type);
bool Serialize(SerialInfo* info) const;
static Packet* Unserialize(UnserialInfo* info);
// These are passed in through the constructor.
std::string tag; /// Used in serialization
double time; /// Timestamp reconstituted as float
struct timeval ts; /// Capture timestamp
const u_char* data; /// Packet data.
uint32 len; /// Actual length on wire
uint32 cap_len; /// Captured packet length
uint32 link_type; /// pcap link_type (DLT_EN10MB, DLT_RAW, etc)
// These are computed from Layer 2 data. These fields are only valid if
// Layer2Valid() returns true.
uint32 hdr_size; /// Layer 2 header size
Layer3Proto l3_proto; /// Layer 3 protocol identified (if any)
uint32 eth_type; /// If L2==ethernet, innermost ethertype field
uint32 vlan; /// (Outermost) VLan tag if any, else 0
private:
// Calculate layer 2 attributes. Sets
void ProcessLayer2();
// Wrapper to generate a packet-level weird.
void Weird(const char* name);
// should we delete associated packet memory upon destruction.
bool free;
// True if L2 processing succeeded.
bool l2_valid;
};
#endif // packet_h