Added more code in the compilation for the PPI linktype: now we generate
code that discards non-802.11 packets. A couple of mods to remove some compilation warnings with VC6.
This commit is contained in:
gianluca
parent
9c308a3a48
commit
ec63ab312c
69
gencode.c
69
gencode.c
|
|
@ -21,7 +21,7 @@
|
|||
*/
|
||||
#ifndef lint
|
||||
static const char rcsid[] _U_ =
|
||||
"@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.281 2007-06-14 18:14:06 gianluca Exp $ (LBL)";
|
||||
"@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.282 2007-06-14 18:49:30 gianluca Exp $ (LBL)";
|
||||
#endif
|
||||
|
||||
#ifdef HAVE_CONFIG_H
|
||||
|
|
@ -100,8 +100,12 @@ static const char rcsid[] _U_ =
|
|||
static jmp_buf top_ctx;
|
||||
static pcap_t *bpf_pcap;
|
||||
|
||||
#ifdef WIN32
|
||||
/* Hack for updating VLAN, MPLS, and PPPoE offsets. */
|
||||
static u_int orig_linktype = (u_int)-1, orig_nl = (u_int)-1, label_stack_depth = (u_int)-1;
|
||||
#else
|
||||
static u_int orig_linktype = -1U, orig_nl = -1U, label_stack_depth = -1U;
|
||||
#endif
|
||||
|
||||
/* XXX */
|
||||
#ifdef PCAP_FDDIPAD
|
||||
|
|
@ -478,6 +482,7 @@ void
|
|||
finish_parse(p)
|
||||
struct block *p;
|
||||
{
|
||||
insert_load_llprefixlen(p);
|
||||
backpatch(p, gen_retblk(snaplen));
|
||||
p->sense = !p->sense;
|
||||
backpatch(p, gen_retblk(0));
|
||||
|
|
@ -498,7 +503,6 @@ finish_parse(p)
|
|||
* require the length of that header, doing more for that
|
||||
* header length isn't really worth the effort.
|
||||
*/
|
||||
insert_load_llprefixlen(root);
|
||||
}
|
||||
|
||||
void
|
||||
|
|
@ -1011,18 +1015,12 @@ init_linktype(p)
|
|||
|
||||
|
||||
/*
|
||||
* TODO GV
|
||||
*
|
||||
* At the moment we treat PPI as normal Radiotap encoded
|
||||
* packets. The difference is in the function that generates
|
||||
* the code at the beginning to compute the header length.
|
||||
* Since this code generator of PPI supports bare 802.11
|
||||
* encapsulation only (i.e. the encapsulated DLT should be
|
||||
* DLT_IEEE802_11) we should generate code to check for this.
|
||||
* Unfortunately given the current structure of the code generator,
|
||||
* generating the proper JMP(x) code to be prepended is problematic.
|
||||
* We just ignore the DLT in the PPI header.
|
||||
*
|
||||
* DLT_IEEE802_11) we generate code to check for this too.
|
||||
*/
|
||||
case DLT_PPI:
|
||||
case DLT_IEEE802_11_RADIO:
|
||||
|
|
@ -1913,32 +1911,29 @@ insert_radiotap_load_llprefixlen(b)
|
|||
}
|
||||
|
||||
/*
|
||||
* TODO GV
|
||||
*
|
||||
* At the moment we treat PPI as normal Radiotap encoded
|
||||
* packets. The difference is in the function that generates
|
||||
* the code at the beginning to compute the header length.
|
||||
* Since this code generator of PPI supports bare 802.11
|
||||
* encapsulation only (i.e. the encapsulated DLT should be
|
||||
* DLT_IEEE802_11) we should generate code to check for this.
|
||||
* Unfortunately given the current structure of the code generator,
|
||||
* generating the proper JMP(x) code to be prepended is problematic.
|
||||
* We just ignore the DLT in the PPI header.
|
||||
*
|
||||
* DLT_IEEE802_11) we generate code to check for this too.
|
||||
*/
|
||||
static void
|
||||
insert_ppi_load_llprefixlen(b)
|
||||
struct block *b;
|
||||
{
|
||||
struct slist *s1, *s2;
|
||||
|
||||
struct slist *s_load_dlt;
|
||||
struct block *new_b;
|
||||
struct block temp;
|
||||
|
||||
/*
|
||||
* Prepend to the statements in this block code to load the
|
||||
* length of the radiotap header into the register assigned
|
||||
* to hold that length, if one has been assigned.
|
||||
*/
|
||||
if (reg_ll_size != -1) {
|
||||
/*
|
||||
/*
|
||||
* The 2 bytes at offsets of 2 and 3 from the beginning
|
||||
* of the radiotap header are the length of the radiotap
|
||||
* header; unfortunately, it's little-endian, so we have
|
||||
|
|
@ -1987,6 +1982,20 @@ insert_ppi_load_llprefixlen(b)
|
|||
*/
|
||||
sappend(s1, b->stmts);
|
||||
b->stmts = s1;
|
||||
|
||||
temp = *b;
|
||||
|
||||
/* Create the statements that check for the DLT
|
||||
*/
|
||||
s_load_dlt = new_stmt(BPF_LD|BPF_W|BPF_ABS);
|
||||
s_load_dlt->s.k = 4;
|
||||
|
||||
new_b = new_block(JMP(BPF_JEQ));
|
||||
|
||||
new_b->stmts = s_load_dlt;
|
||||
new_b->s.k = SWAPLONG(DLT_IEEE802_11);
|
||||
|
||||
gen_and(new_b,b);
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -1997,18 +2006,12 @@ insert_load_llprefixlen(b)
|
|||
switch (linktype) {
|
||||
|
||||
/*
|
||||
* TODO GV
|
||||
*
|
||||
* At the moment we treat PPI as normal Radiotap encoded
|
||||
* packets. The difference is in the function that generates
|
||||
* the code at the beginning to compute the header length.
|
||||
* Since this code generator of PPI supports bare 802.11
|
||||
* encapsulation only (i.e. the encapsulated DLT should be
|
||||
* DLT_IEEE802_11) we should generate code to check for this.
|
||||
* Unfortunately given the current structure of the code generator,
|
||||
* generating the proper JMP(x) code to be prepended is problematic.
|
||||
* We just ignore the DLT in the PPI header.
|
||||
*
|
||||
* DLT_IEEE802_11) we generate code to check for this too.
|
||||
*/
|
||||
case DLT_PPI:
|
||||
insert_ppi_load_llprefixlen(b);
|
||||
|
|
@ -2044,18 +2047,12 @@ gen_radiotap_llprefixlen(void)
|
|||
}
|
||||
|
||||
/*
|
||||
* TODO GV
|
||||
*
|
||||
* At the moment we treat PPI as normal Radiotap encoded
|
||||
* packets. The difference is in the function that generates
|
||||
* the code at the beginning to compute the header length.
|
||||
* Since this code generator of PPI supports bare 802.11
|
||||
* encapsulation only (i.e. the encapsulated DLT should be
|
||||
* DLT_IEEE802_11) we should generate code to check for this.
|
||||
* Unfortunately given the current structure of the code generator,
|
||||
* generating the proper JMP(x) code to be prepended is problematic.
|
||||
* We just ignore the DLT in the PPI header.
|
||||
*
|
||||
* DLT_IEEE802_11) we generate code to check for this too.
|
||||
*/
|
||||
static struct slist *
|
||||
gen_ppi_llprefixlen(void)
|
||||
|
|
@ -3306,22 +3303,22 @@ gen_dnhostop(addr, dir)
|
|||
tmp = gen_mcmp(OR_NET, 2, BPF_H,
|
||||
(bpf_int32)ntohs(0x0681), (bpf_int32)ntohs(0x07FF));
|
||||
b1 = gen_cmp(OR_NET, 2 + 1 + offset_lh,
|
||||
BPF_H, (bpf_int32)ntohs(addr));
|
||||
BPF_H, (bpf_int32)ntohs((u_short)addr));
|
||||
gen_and(tmp, b1);
|
||||
/* Check for pad = 0, long header case */
|
||||
tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x06, (bpf_int32)0x7);
|
||||
b2 = gen_cmp(OR_NET, 2 + offset_lh, BPF_H, (bpf_int32)ntohs(addr));
|
||||
b2 = gen_cmp(OR_NET, 2 + offset_lh, BPF_H, (bpf_int32)ntohs((u_short)addr));
|
||||
gen_and(tmp, b2);
|
||||
gen_or(b2, b1);
|
||||
/* Check for pad = 1, short header case */
|
||||
tmp = gen_mcmp(OR_NET, 2, BPF_H,
|
||||
(bpf_int32)ntohs(0x0281), (bpf_int32)ntohs(0x07FF));
|
||||
b2 = gen_cmp(OR_NET, 2 + 1 + offset_sh, BPF_H, (bpf_int32)ntohs(addr));
|
||||
b2 = gen_cmp(OR_NET, 2 + 1 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr));
|
||||
gen_and(tmp, b2);
|
||||
gen_or(b2, b1);
|
||||
/* Check for pad = 0, short header case */
|
||||
tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x02, (bpf_int32)0x7);
|
||||
b2 = gen_cmp(OR_NET, 2 + offset_sh, BPF_H, (bpf_int32)ntohs(addr));
|
||||
b2 = gen_cmp(OR_NET, 2 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr));
|
||||
gen_and(tmp, b2);
|
||||
gen_or(b2, b1);
|
||||
|
||||
|
|
|
|||
Reference in New Issue