/*-
- ptag = n:ipv4{len=int, protocol=int, src=ipaddr, dst=ipaddr, payload=str, ptag=int, options=ip_options}
ptag is optional, defaults to creating a new protocol block
options is optional
*/
static int lnet_ipv4 (lua_State *L)
{
libnet_t** ud = luaL_checkudata(L, 1, L_NET_REGID);
luaL_argcheck(L, *ud, 1, "net has been destroyed");
int len = v_arg_integer(L, 2, "len"); // FIXME - should be optional!
int tos = 0;
int id = 0;
int offset = 0;
int ttl = 64;
int protocol = v_arg_integer(L, 2, "protocol");
int cksum = 0; // 0 is a flag requesting libnet to fill in correct cksum
const char* src = v_arg_string(L, 2, "src");
const char* dst = v_arg_string(L, 2, "dst");
size_t payloadsz = 0;
const char* payload = v_arg_lstring(L, 2, "payload", &payloadsz, "");
int ptag = lnet_arg_ptag(L, 2);
int options_ptag = 0;
size_t optionsz = 0;
const char* options = v_arg_lstring(L, 2, "options", &optionsz, "");
if(payloadsz == 0) {
payload = NULL;
}
#ifdef NET_DUMP
printf("net ipv4 src %s dst %s len %d payloadsz %lu ptag %d optionsz %lu\n", src, dst, len, payloadsz, ptag, optionsz);
#endif
uint32_t src_n = check_ip_pton(L, src, "src");
uint32_t dst_n = check_ip_pton(L, dst, "dst");
if(ptag) {
/* Modifying exist IPv4 packet, so find the preceeding options block (we
* _always_ push an options block, perhaps empty, to make this easy).
*/
libnet_pblock_t* p = libnet_pblock_find(*ud, ptag);
if(!p)
return check_error(L, *ud, -1);
options_ptag = p->prev->ptag;
}
#ifdef NET_DUMP
printf(" options_ptag %d optionsz %lu\n", options_ptag, optionsz);
#endif
options_ptag = libnet_build_ipv4_options((uint8_t*) options,
optionsz, *ud, options_ptag);
check_error(L, *ud, options_ptag);
ptag = libnet_build_ipv4(len, tos, id, offset, ttl, protocol, cksum, src_n,
dst_n, (uint8_t*) payload, payloadsz, *ud, ptag);
check_error(L, *ud, ptag);
lua_pushinteger(L, ptag);
return 1;
}
/*-
-- ptag = net:udp{src=NUM, dst=NUM, len=NUM, payload=STR, ptag=int}
Build UDP packet inside net context.
ptag is optional, defaults to creating a new protocol block
*/
static int lnet_udp (lua_State *L)
{
libnet_t* ud = checkudata(L);
int src = v_arg_integer(L, 2, "src");
int dst = v_arg_integer(L, 2, "dst");
uint32_t payloadsz = 0;
const uint8_t* payload = checkpayload(L, 2, &payloadsz);
int len = v_arg_integer_opt(L, 2, "len", LIBNET_UDP_H + payloadsz);
int cksum = 0;
int ptag = lnet_arg_ptag(L, ud, 2, LIBNET_PBLOCK_UDP_H);
ptag = libnet_build_udp(src, dst, len, cksum, payload, payloadsz, ud, ptag);
check_error(L, ud, ptag);
lua_pushinteger(L, ptag);
return 1;
}
/*-
-- ptag = net:igmp{type=NUM, code=NUM, ip=IP, payload=STR, ptag=int}
Build IGMP packet inside net context.
ptag is optional, defaults to creating a new protocol block
*/
static int lnet_igmp (lua_State *L)
{
libnet_t* ud = checkudata(L);
int type = v_arg_integer(L, 2, "type");
int code = v_arg_integer(L, 2, "code");
const char* ip = v_arg_string(L, 2, "ip");
uint32_t ip_n = check_ip_pton(L, ip, "ip");
uint32_t payloadsz = 0;
const uint8_t* payload = checkpayload(L, 2, &payloadsz);
int cksum = 0;
int ptag = lnet_arg_ptag(L, ud, 2, LIBNET_PBLOCK_IGMP_H);
ptag = libnet_build_igmp(type, code, cksum, ip_n, payload, payloadsz, ud, ptag);
check_error(L, ud, ptag);
lua_pushinteger(L, ptag);
return 1;
}
/*-
- ptag = net:udp{src=NUM, dst=NUM, len=NUM, payload=STR, ptag=int}
Build UDP packet inside net context.
ptag is optional, defaults to creating a new protocol block
*/
static int lnet_udp (lua_State *L)
{
libnet_t** ud = luaL_checkudata(L, 1, L_NET_REGID);
luaL_argcheck(L, *ud, 1, "net has been destroyed");
int src = v_arg_integer(L, 2, "src");
int dst = v_arg_integer(L, 2, "dst");
size_t payloadsz = 0;
const char* payload = v_arg_lstring(L, 2, "payload", &payloadsz, "");
int len = v_arg_integer_opt(L, 2, "len", LIBNET_UDP_H + payloadsz);
int cksum = 0;
int ptag = lnet_arg_ptag(L, 2);
if(payloadsz == 0) {
payload = NULL;
}
ptag = libnet_build_udp(src, dst, len, cksum, (uint8_t*)payload, payloadsz, *ud, ptag);
check_error(L, *ud, ptag);
lua_pushinteger(L, ptag);
return 1;
}
/*-
-- ptag = n:ipv4{
-- required arguments
src=ipaddr,
dst=ipaddr,
protocol=int,
-- optional arguments
ptag=int,
payload=str,
options=ip_options,
len=int, -- default is correct length
tos=int,
id=int,
frag=int,
ttl=int, -- defaults to 64
}
ptag is optional, defaults to creating a new protocol block
options is optional
*/
static int lnet_ipv4 (lua_State *L)
{
libnet_t* ud = checkudata(L);
const char* src = v_arg_string(L, 2, "src");
const char* dst = v_arg_string(L, 2, "dst");
uint32_t src_n = check_ip_pton(L, src, "src");
uint32_t dst_n = check_ip_pton(L, dst, "dst");
int protocol = v_arg_integer(L, 2, "protocol"); /* TODO make optional */
int ptag = lnet_arg_ptag(L, ud, 2, LIBNET_PBLOCK_IPV4_H);
uint32_t payloadsz = 0;
const uint8_t* payload = checkpayload(L, 2, &payloadsz);
int options_ptag = 0;
uint32_t optionsz = 0;
const uint8_t* options = checklbuffer(L, 2, "options", &optionsz);
int len = v_arg_integer_opt(L, 2, "len", -1);
int tos = v_arg_integer_opt(L, 2, "tos", 0);
int id = v_arg_integer_opt(L, 2, "id", 0);
int frag = v_arg_integer_opt(L, 2, "frag", 0);
int ttl = v_arg_integer_opt(L, 2, "ttl", 64);
int cksum = 0; /* 0 is a flag requesting libnet to fill in correct cksum */
libnet_pblock_t* oblock = NULL;
#ifdef NET_DUMP
printf("net ipv4 src %s dst %s len %d payloadsz %lu ptag %d optionsz %lu\n", src, dst, len, payloadsz, ptag, optionsz);
#endif
oblock = ptag ? libnet_pblock_find(ud, ptag)->prev : ud->pblock_end;
if(!oblock || oblock->type != LIBNET_PBLOCK_IPO_H)
oblock = NULL;
else
options_ptag = oblock->ptag;
#ifdef NET_DUMP
printf(" options_ptag %d optionsz from %lu to %lu\n",
options_ptag, oblock ? oblock->b_len : 0, optionsz);
#endif
/* Two initial states possible:
* - has prev ip options block, or not
* Two final states desired:
* - has prev ip options block, or not
*/
if(!options) {
libnet_pblock_delete(ud, oblock);
} else {
options_ptag = libnet_build_ipv4_options(options, optionsz, ud, options_ptag);
check_error(L, ud, options_ptag);
if(oblock) {
/* we replaced an existing block that was correctly placed */
} else if(ptag) {
libnet_pblock_insert_before(ud, ptag, options_ptag);
} else {
/* we just pushed a new options block, and are about to push a new ip block */
}
}
/* If len unspecified, rewrite it to be len of ipv4 pblock + previous blocks. */
/* FIXME I don't think defaulting to end is correct
-- libnet doesn't have a generic icmp construction api, see bug#1373
local function build_icmp(n, icmp)
local typecode = string.char(assert(icmp.type), assert(icmp.code))
local data = icmp.data or ""
local checksum = net.checksum(typecode, "\0\0", data)
local packet = typecode..checksum..data
return n:ipv4{
src = arg.localip,
dst = arg.dutip,
protocol = 1, -- ICMP is protocol 1 FIXME get from iana.ip.types.icmp
payload = packet,
len = 20 + #packet,
ptag = icmp.ptag
}
end
getmetatable(n).icmp = build_icmp
-- set up the pblock stack, top to bottom
local ptag = n:icmp{type=0, code=0}
n:eth{src=arg.localmac, dst=arg.dutmac}
n:icmp{ptag=ptag, type=type, code=code, payload=data}
print(n:dump())
print(n:get_ipv4())
~/w/wt/achilles-engine/data/Plugins/Grammar % sudo ./icmp-data-grammar-l2 dutip=1.1.1.1 localdev=lo localip=2.2.2.2 dutmac=11:11:11:11:11:11 localmac=22:22:22:22:22:22 pcap=pc.pcap
tag 2 flags 0 type ipdata/0xf buf 0x6541e0 b_len 4 h_len 4 copied 4 prev -1 next 1
tag 1 flags 1 type ipv4/0xd buf 0x6582f0 b_len 20 h_len 20 copied 20 prev 2 next 3
tag 3 flags 0 type eth/0x4 buf 0x647580 b_len 14 h_len 0 copied 14 prev 1 next -1
link_offset 14 aligner 0 total_size 38 nblocks 3
Total:1
Subtest 1: ICMP type 0 code 1 with payload size 1
tag 2 flags 0 type ipdata/0xf buf 0x6541e0 b_len 4 h_len 4 copied 4 prev -1 next 1
tag 1 flags 1 type ipv4/0xd buf 0x6582f0 b_len 20 h_len 20 copied 20 prev 2 next 3
tag 3 flags 0 type eth/0x4 buf 0x647580 b_len 14 h_len 0 copied 14 prev 1 next -1
link_offset 14 aligner 0 total_size 38 nblocks 3
{
ptag = 1, protocol = 1, _iphl = 5, id = 0, options = "", dst = "1.1.1.1", src = "2.2.2.2", _sum = 0, _ipv = 4, tos = 0, _len = 28, ttl = 64, frag = 0
}
============>> note that _len is 28, it should be 24
*/
if(len < 0) {
libnet_pblock_t* p = ptag ? libnet_pblock_find(ud, ptag)->prev : ud->pblock_end;
len = LIBNET_IPV4_H + payloadsz;
while(p) {
len += p->b_len;
p = p->prev;
}
}
ptag = libnet_build_ipv4(
len, tos, id, frag, ttl, protocol, cksum,
src_n, dst_n,
payload, payloadsz,
ud, ptag);
check_error(L, ud, ptag);
lua_pushinteger(L, ptag);
return 1;
}
/*-
-- ptag = n:tcp{
-- required arguments
src=port,
dst=port,
seq=int,
ack=int,
flags=int,
win=int,
urg=int,
-- optional arguments
ptag=int,
payload=str,
options=tcp_options,
}
ptag is optional, defaults to creating a new protocol block
options is optional
*/
static int lnet_tcp (lua_State *L)
{
libnet_t* ud = checkudata(L);
int src = v_arg_integer(L, 2, "src");
int dst = v_arg_integer(L, 2, "dst");
int seq = v_arg_integer(L, 2, "seq");
int ack = v_arg_integer(L, 2, "ack");
int flags = v_arg_integer(L, 2, "flags");
int win = v_arg_integer(L, 2, "win");
int urg = v_arg_integer(L, 2, "urg");
int ptag = lnet_arg_ptag(L, ud, 2, LIBNET_PBLOCK_TCP_H);
uint32_t payloadsz = 0;
const uint8_t* payload = checkpayload(L, 2, &payloadsz);
int options_ptag = 0;
uint32_t optionsz = 0;
const uint8_t* options = checklbuffer(L, 2, "options", &optionsz);
int cksum = 0; /* 0 is a flag requesting libnet to fill in correct cksum */
libnet_pblock_t* oblock = NULL;
int len = 0; /* libnet needs len for checksum calculation */
oblock = ptag ? libnet_pblock_find(ud, ptag)->prev : ud->pblock_end;
if(!oblock || oblock->type != LIBNET_PBLOCK_TCPO_H)
oblock = NULL;
else
options_ptag = oblock->ptag;
/* Two initial states possible:
* - has prev ip options block, or not
* Two final states desired:
* - has prev ip options block, or not
*/
if(!options) {
libnet_pblock_delete(ud, oblock);
} else {
options_ptag = libnet_build_tcp_options(options, optionsz, ud, options_ptag);
check_error(L, ud, options_ptag);
if(oblock) {
/* we replaced an existing block that was correctly placed */
} else if(ptag) {
libnet_pblock_insert_before(ud, ptag, options_ptag);
} else {
/* we just pushed a new options block, and are about to push a new ip block */
}
}
/* Rewrite len to be len of tcp pblock + previous blocks. */
{
libnet_pblock_t* p = ptag ? libnet_pblock_find(ud, ptag)->prev : ud->pblock_end;
len = LIBNET_TCP_H + payloadsz;
while(p) {
/* don't count tcpdata pblock... we will replace it payloadsz data below */
if(p->type != LIBNET_PBLOCK_TCPDATA)
len += p->b_len;
p = p->prev;
}
}
ptag = libnet_build_tcp(
src, dst, seq, ack, flags, win, cksum, urg,
len,
payload, payloadsz,
ud, ptag);
check_error(L, ud, ptag);
lua_pushinteger(L, ptag);
return 1;
}
