metasploit-framework/external/ruby-pcapx/packet.c

340 lines
8.9 KiB
C

/*
* packet.c
*
* $Id: packet.c,v 1.4 2000/08/13 06:56:15 fukusima Exp $
*
* Copyright (C) 1998-2000 Masaki Fukushima
*/
#include "ruby.h"
#include "ruby_pcap.h"
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/if_ether.h>
#define DL_HDR(pkt) ((u_char *)LAYER2_HDR(pkt))
#define DL_DATA(pkt) ((u_char *)LAYER3_HDR(pkt))
VALUE cPacket;
static VALUE mMarshal;
int id_load;
int id_dump;
/* called from GC */
static void
free_packet(pkt)
struct packet_object *pkt;
{
DEBUG_PRINT("free_packet");
free(pkt);
}
/* called from GC */
static void
mark_packet(pkt)
struct packet_object *pkt;
{
DEBUG_PRINT("mark_packet");
if (pkt->udata != Qnil)
rb_gc_mark(pkt->udata);
}
struct datalink_type {
int type;
int nltype_off; /* offset of network-layer type field */
int nl_off; /* offset of network-layer header */
};
/* supported datalink types */
static struct datalink_type datalinks[] = {
{ DLT_NULL, -2, 4 },
{ DLT_EN10MB, 12, 14 },
{ DLT_IEEE802, 20, 22 },
{ DLT_SLIP, -2, 16 },
{ DLT_PPP, 2, 4 },
#ifndef PCAP_FDDIPAD
{ DLT_FDDI, 19, 21 }, /* 10: DLT_FDDI */
#else
{ DLT_FDDI, 19 + PCAP_FDDIPAD, 21 + PCAP_FDDIPAD },
#endif
{ DLT_ATM_RFC1483, 6, 8 },
{ DLT_RAW, -2, 0 },
{ DLT_SLIP_BSDOS, -2, 24 },
{ DLT_PPP_BSDOS, -2, 24 },
{ DLT_IEEE802_11, -1, 0 },
{ DLT_IEEE802_11_RADIO, -1, 0 }, /* radiotap is padded to 64 bytes */
{ DLT_IEEE802_11_RADIO_AVS, -1, 0 },
{ DLT_LINUX_SLL, -1, 0 },
{ DLT_PRISM_HEADER, -1, 0 },
{ DLT_AIRONET_HEADER, -1, 0 },
{ 255, 0, 0 }
};
VALUE
new_packet(data, pkthdr, dl_type)
const u_char *data;
const struct pcap_pkthdr *pkthdr;
int dl_type;
{
VALUE class;
struct packet_object *pkt;
int nl_off, nl_len, nltype_off, nl_type, pad, i;
unsigned short *f;
int t = -1;
DEBUG_PRINT("new_packet");
// This is slow and needs to be rewritten
for (i = 0; datalinks[i].type != 255; i++) {
if (datalinks[i].type == dl_type) {
t = i;
break;
}
}
/* check nework layer type and offset */
if (t == -1)
rb_raise(ePcapError, "Unknown data-link type (%d)", dl_type);
nltype_off = datalinks[t].nltype_off;
nl_off = datalinks[t].nl_off;
/* parse the DLT header to figure it out */
if (nltype_off == -1) {
switch(dl_type) {
case DLT_LINUX_SLL:
default:
if (pkthdr->caplen > 16) {
f = (unsigned short *)(data + 4);
i = ntohs(*f);
if (pkthdr->caplen > i + 16 ) {
nltype_off = i + 14;
nl_off = i + 16;
}
}
break;
}
}
/* assume this is raw IP */
if (nltype_off == -2) {
nl_type = ETHERTYPE_IP;
/* assume Ether Type value */
} else if (nltype_off != -1) {
nl_type = ntohs(*(u_short *)(data + nltype_off));
}
/* alloc memory and setup packet_object */
pad = nl_off % 4; /* align network layer header */
pkt = xmalloc(sizeof(*pkt) + pad + pkthdr->caplen);
pkt->hdr.version = PACKET_MARSHAL_VERSION;
pkt->hdr.flags = 0;
pkt->hdr.dl_type = dl_type;
pkt->hdr.layer3_off = OFF_NONEXIST;
pkt->hdr.layer4_off = OFF_NONEXIST;
pkt->hdr.layer5_off = OFF_NONEXIST;
pkt->hdr.pkthdr = *pkthdr;
pkt->data = (u_char *)pkt + sizeof(*pkt) + pad;
pkt->udata = Qnil;
memcpy(pkt->data, data, pkthdr->caplen);
nl_len = pkthdr->caplen - nl_off;
if (nl_off >= 0 && nl_len > 0)
pkt->hdr.layer3_off = nl_off;
/* setup upper layer */
class = cPacket;
if (pkt->hdr.layer3_off != OFF_NONEXIST) {
switch (nl_type) {
case ETHERTYPE_IP:
class = setup_ip_packet(pkt, nl_len);
break;
}
}
#if DEBUG
if (ruby_debug && TYPE(class) != T_CLASS) {
rb_fatal("not class");
}
#endif
return Data_Wrap_Struct(class, mark_packet, free_packet, pkt);
}
static VALUE
packet_load(class, str)
VALUE class;
VALUE str;
{
struct packet_object *pkt = NULL;
struct packet_object_header *hdr;
int version;
u_char *str_ptr;
DEBUG_PRINT("packet_load");
str_ptr = RSTRING(str)->ptr;
hdr = (struct packet_object_header *)str_ptr;
version = hdr->version;
if (version == PACKET_MARSHAL_VERSION) {
bpf_u_int32 caplen;
u_short layer3_off;
int pad;
caplen = ntohl(hdr->pkthdr.caplen);
layer3_off = ntohs(hdr->layer3_off);
pad = layer3_off % 4; /* align network layer header */
pkt = (struct packet_object *)xmalloc(sizeof(*pkt) + pad + caplen);
pkt->hdr.version = PACKET_MARSHAL_VERSION;
pkt->hdr.flags = hdr->flags;
pkt->hdr.dl_type = hdr->dl_type;
pkt->hdr.layer3_off = ntohs(hdr->layer3_off);
pkt->hdr.layer4_off = ntohs(hdr->layer4_off);
pkt->hdr.layer5_off = ntohs(hdr->layer5_off);
pkt->hdr.pkthdr.ts.tv_sec = ntohl(hdr->pkthdr.ts.tv_sec);
pkt->hdr.pkthdr.ts.tv_usec = ntohl(hdr->pkthdr.ts.tv_usec);
pkt->hdr.pkthdr.caplen = ntohl(hdr->pkthdr.caplen);
pkt->hdr.pkthdr.len = ntohl(hdr->pkthdr.len);
pkt->data = (u_char *)pkt + sizeof(*pkt) + pad;
memcpy(pkt->data, str_ptr + sizeof(*hdr), caplen);
if (PKTFLAG_TEST(pkt, POH_UDATA)) {
int l = sizeof(*hdr) + caplen;
VALUE ustr = rb_str_substr(str, l, RSTRING(str)->len - l);
pkt->udata = rb_funcall(mMarshal, id_load, 1, ustr);
} else {
pkt->udata = Qnil;
}
PKTFLAG_SET(pkt, POH_UDATA, (pkt->udata != Qnil));
} else {
rb_raise(rb_eArgError, "unknown packet marshal version(0x%x)", version);
}
if (pkt != NULL)
return Data_Wrap_Struct(class, mark_packet, free_packet, pkt);
else
return Qnil;
}
static VALUE
packet_dump(self, limit)
VALUE self;
VALUE limit;
{
struct packet_object *pkt;
struct packet_object_header hdr;
VALUE str;
DEBUG_PRINT("packet_dump");
GetPacket(self, pkt);
hdr.version = PACKET_MARSHAL_VERSION;
hdr.flags = pkt->hdr.flags;
hdr.dl_type = pkt->hdr.dl_type;
hdr.layer3_off = htons(pkt->hdr.layer3_off);
hdr.layer4_off = htons(pkt->hdr.layer4_off);
hdr.layer5_off = htons(pkt->hdr.layer5_off);
hdr.pkthdr.ts.tv_sec = htonl(pkt->hdr.pkthdr.ts.tv_sec);
hdr.pkthdr.ts.tv_usec = htonl(pkt->hdr.pkthdr.ts.tv_usec);
hdr.pkthdr.caplen = htonl(pkt->hdr.pkthdr.caplen);
hdr.pkthdr.len = htonl(pkt->hdr.pkthdr.len);
str = rb_str_new((char *)&hdr, sizeof(hdr));
rb_str_cat(str, pkt->data, pkt->hdr.pkthdr.caplen);
if (pkt->udata != Qnil) {
VALUE ustr;
ustr = rb_funcall(mMarshal, id_dump, 1, pkt->udata);
rb_str_concat(str, ustr);
}
return str;
}
static VALUE
packet_set_udata(self, val)
VALUE self;
VALUE val;
{
struct packet_object *pkt;
DEBUG_PRINT("packet_set_udata");
GetPacket(self, pkt);
pkt->udata = val;
PKTFLAG_SET(pkt, POH_UDATA, (val != Qnil));
return val;
}
static VALUE
packet_match(self, expr)
VALUE self;
VALUE expr;
{
if (IsKindOf(expr, cFilter)) {
return filter_match(expr, self);
}
rb_raise(rb_eArgError, "Not Filter");
}
#define PACKET_METHOD(func, val) \
static VALUE\
(func)(self)\
VALUE self;\
{\
struct packet_object *pkt;\
\
DEBUG_PRINT(#func);\
GetPacket(self, pkt);\
return (val);\
}
PACKET_METHOD(packet_get_udata, pkt->udata);
PACKET_METHOD(packet_datalink, INT2FIX(pkt->hdr.dl_type));
PACKET_METHOD(packet_ip, rb_obj_is_kind_of(self, cIPPacket));
PACKET_METHOD(packet_tcp, rb_obj_is_kind_of(self, cTCPPacket));
PACKET_METHOD(packet_udp, rb_obj_is_kind_of(self, cUDPPacket));
PACKET_METHOD(packet_length, UINT32_2_NUM(pkt->hdr.pkthdr.len));
PACKET_METHOD(packet_caplen, UINT32_2_NUM(pkt->hdr.pkthdr.caplen));
PACKET_METHOD(packet_time, rb_time_new(pkt->hdr.pkthdr.ts.tv_sec,
pkt->hdr.pkthdr.ts.tv_usec));
PACKET_METHOD(packet_time_i, rb_int2inum(pkt->hdr.pkthdr.ts.tv_sec));
PACKET_METHOD(packet_raw_data, rb_str_new(pkt->data, pkt->hdr.pkthdr.caplen));
void
Init_packet(void)
{
DEBUG_PRINT("Init_packet");
/* define class Packet */
cPacket = rb_define_class_under(mPcap, "Packet", rb_cObject);
rb_define_singleton_method(cPacket, "_load", packet_load, 1);
rb_define_method(cPacket, "_dump", packet_dump, 1);
/* marshal backward compatibility */
rb_define_singleton_method(cPacket, "_load_from", packet_load, 1);
rb_define_method(cPacket, "_dump_to", packet_dump, 1);
rb_define_method(cPacket, "udata", packet_get_udata, 0);
rb_define_method(cPacket, "udata=", packet_set_udata, 1);
rb_define_method(cPacket, "datalink", packet_datalink, 0);
rb_define_method(cPacket, "ip?", packet_ip, 0);
rb_define_method(cPacket, "tcp?", packet_tcp, 0);
rb_define_method(cPacket, "udp?", packet_udp, 0);
rb_define_method(cPacket, "length", packet_length, 0);
rb_define_method(cPacket, "size", packet_length, 0);
rb_define_method(cPacket, "caplen", packet_caplen, 0);
rb_define_method(cPacket, "time", packet_time, 0);
rb_define_method(cPacket, "time_i", packet_time_i, 0);
rb_define_method(cPacket, "raw_data", packet_raw_data, 0);
rb_define_method(cPacket, "=~", packet_match, 1);
/* mMarshal in ruby/marshal.c is static. Why? */
mMarshal = rb_eval_string("Marshal");
id_load = rb_intern("load");
id_dump = rb_intern("dump");
Init_ip_packet();
}