*/
#ifndef lint
static const char rcsid[] _U_ =
- "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.48 2007-06-11 09:52:04 guy Exp $ (LBL)";
+ "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.49 2007-06-13 22:51:07 gianluca Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
static struct block *gen_ether_linktype(int);
static struct block *gen_linux_sll_linktype(int);
static void insert_radiotap_load_llprefixlen(struct block *);
+static void insert_ppi_load_llprefixlen(struct block *);
static void insert_load_llprefixlen(struct block *);
static struct slist *gen_llprefixlen(void);
static struct block *gen_linktype(int);
off_nl_nosnap = 27; /* Radio+802.11+802.2 */
return;
+
+ /*
+ * 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.
+ *
+ */
+ case DLT_PPI:
case DLT_IEEE802_11_RADIO:
/*
* Same as 802.11, but with an additional header before
return s;
}
+
/*
* Load a value relative to the beginning of the specified header.
*/
}
}
+/*
+ * 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.
+ *
+ */
+static void
+insert_ppi_load_llprefixlen(b)
+ struct block *b;
+{
+ struct slist *s1, *s2;
+
+ /*
+ * 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
+ * to load it a byte at a time and construct the value.
+ */
+
+ /*
+ * Load the high-order byte, at an offset of 3, shift it
+ * left a byte, and put the result in the X register.
+ */
+ s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
+ s1->s.k = 3;
+ s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
+ sappend(s1, s2);
+ s2->s.k = 8;
+ s2 = new_stmt(BPF_MISC|BPF_TAX);
+ sappend(s1, s2);
+
+ /*
+ * Load the next byte, at an offset of 2, and OR the
+ * value from the X register into it.
+ */
+ s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
+ sappend(s1, s2);
+ s2->s.k = 2;
+ s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X);
+ sappend(s1, s2);
+
+ /*
+ * Now allocate a register to hold that value and store
+ * it.
+ */
+ s2 = new_stmt(BPF_ST);
+ s2->s.k = reg_ll_size;
+ sappend(s1, s2);
+
+ /*
+ * Now move it into the X register.
+ */
+ s2 = new_stmt(BPF_MISC|BPF_TAX);
+ sappend(s1, s2);
+
+ /*
+ * Now append all the existing statements in this
+ * block to these statements.
+ */
+ sappend(s1, b->stmts);
+ b->stmts = s1;
+ }
+}
static void
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.
+ *
+ */
+ case DLT_PPI:
+ insert_ppi_load_llprefixlen(b);
+ break;
+
case DLT_IEEE802_11_RADIO:
insert_radiotap_load_llprefixlen(b);
+ break;
}
}
return s;
}
+/*
+ * 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.
+ *
+ */
+static struct slist *
+gen_ppi_llprefixlen(void)
+{
+ struct slist *s;
+
+ if (reg_ll_size == -1) {
+ /*
+ * We haven't yet assigned a register for the length
+ * of the radiotap header; allocate one.
+ */
+ reg_ll_size = alloc_reg();
+ }
+
+ /*
+ * Load the register containing the radiotap length
+ * into the X register.
+ */
+ s = new_stmt(BPF_LDX|BPF_MEM);
+ s->s.k = reg_ll_size;
+ return s;
+}
+
+
+
/*
* Generate code to compute the link-layer header length, if necessary,
* putting it into the X register, and to return either a pointer to a
{
switch (linktype) {
+ case DLT_PPI:
+ return gen_ppi_llprefixlen();
+
+
case DLT_IEEE802_11_RADIO:
return gen_radiotap_llprefixlen();
}
break;
+ case DLT_PPI:
case DLT_FDDI:
case DLT_IEEE802:
case DLT_IEEE802_11:
break;
case DLT_IEEE802_11:
case DLT_IEEE802_11_RADIO_AVS:
+ case DLT_PPI:
case DLT_IEEE802_11_RADIO:
case DLT_PRISM_HEADER:
b0 = gen_wlanhostop(eaddr, Q_OR);
if (linktype == DLT_IEEE802_11_RADIO)
bpf_error("'protochain' not supported with radiotap headers");
+ if (linktype == DLT_PPI)
+ bpf_error("'protochain' not supported with PPI headers");
+
no_optimize = 1; /*this code is not compatible with optimzer yet */
/*
#endif
}
+
/*
* Generate code that checks whether the packet is a packet for protocol
* <proto> and whether the type field in that protocol's header has
case DLT_IEEE802_11_RADIO_AVS:
case DLT_IEEE802_11_RADIO:
case DLT_PRISM_HEADER:
+ case DLT_PPI:
eaddr = pcap_ether_hostton(name);
if (eaddr == NULL)
bpf_error(
/* NOTREACHED */
}
/* NOTREACHED */
+ return NULL;
}
struct block *
bpf_error("invalid qualifier against IPv6 address");
/* NOTREACHED */
}
+ return NULL;
}
#endif /*INET6*/
return gen_fhostop(eaddr, (int)q.dir);
case DLT_IEEE802:
return gen_thostop(eaddr, (int)q.dir);
- case DLT_IEEE802_11:
- case DLT_IEEE802_11_RADIO_AVS:
- case DLT_IEEE802_11_RADIO:
- case DLT_PRISM_HEADER:
- return gen_wlanhostop(eaddr, (int)q.dir);
- case DLT_SUNATM:
- if (is_lane) {
- /*
- * Check that the packet doesn't begin with an
- * LE Control marker. (We've already generated
- * a test for LANE.)
- */
- tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
- 0xFF00);
- gen_not(tmp);
-
- /*
- * Now check the MAC address.
- */
- b = gen_ehostop(eaddr, (int)q.dir);
- gen_and(tmp, b);
- return b;
- }
- break;
- case DLT_IP_OVER_FC:
+ case DLT_IEEE802_11:
+ case DLT_IEEE802_11_RADIO_AVS:
+ case DLT_IEEE802_11_RADIO:
+ case DLT_PRISM_HEADER:
+ case DLT_PPI:
+ return gen_wlanhostop(eaddr, (int)q.dir);
+ case DLT_SUNATM:
+ if (is_lane) {
+ /*
+ * Check that the packet doesn't begin with an
+ * LE Control marker. (We've already generated
+ * a test for LANE.)
+ */
+ tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
+ 0xFF00);
+ gen_not(tmp);
+
+ /*
+ * Now check the MAC address.
+ */
+ b = gen_ehostop(eaddr, (int)q.dir);
+ gen_and(tmp, b);
+ return b;
+ }
+ break;
+ case DLT_IP_OVER_FC:
return gen_ipfchostop(eaddr, (int)q.dir);
default:
- bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
+ bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
break;
}
}
bpf_error("ethernet address used in non-ether expression");
/* NOTREACHED */
+ return NULL;
}
void
}
bpf_error("too many registers needed to evaluate expression");
/* NOTREACHED */
+ return 0;
}
/*
case DLT_IEEE802_11:
case DLT_IEEE802_11_RADIO_AVS:
case DLT_IEEE802_11_RADIO:
+ case DLT_PPI:
case DLT_PRISM_HEADER:
return gen_wlanhostop(ebroadcast, Q_DST);
case DLT_IP_OVER_FC:
}
bpf_error("only link-layer/IP broadcast filters supported");
/* NOTREACHED */
+ return NULL;
}
/*
return gen_mac_multicast(2);
case DLT_IEEE802_11:
case DLT_IEEE802_11_RADIO_AVS:
+ case DLT_PPI:
case DLT_IEEE802_11_RADIO:
case DLT_PRISM_HEADER:
/*
}
bpf_error("link-layer multicast filters supported only on ethernet/FDDI/token ring/ARCNET/802.11/ATM LANE/Fibre Channel");
/* NOTREACHED */
+ return NULL;
}
/*
}
bpf_error("ARCnet address used in non-arc expression");
/* NOTREACHED */
+ return NULL;
}
static struct block *
projects / libpcap / commitdiff
