*/
#ifndef lint
static const char rcsid[] =
- "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.178 2002-08-08 11:07:27 guy Exp $ (LBL)";
+ "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.179 2002-08-11 18:27:13 guy Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
static struct block *gen_uncond(int);
static inline struct block *gen_true(void);
static inline struct block *gen_false(void);
+static struct block *gen_ether_linktype(int);
static struct block *gen_linktype(int);
static struct block *gen_snap(bpf_u_int32, bpf_u_int32, u_int);
static struct block *gen_llc(int);
* layer. These variables give the necessary offsets.
*/
+/*
+ * This is the offset of the beginning of the MAC-layer header.
+ * It's usually 0, except for ATM LANE.
+ */
+static u_int off_mac;
+
/*
* "off_linktype" is the offset to information in the link-layer header
* giving the packet type.
*/
static int is_atm = 0;
+/*
+ * TRUE if "lane" appeared in the filter; it causes us to generate
+ * code that assumes LANE rather than LLC-encapsulated traffic in SunATM.
+ */
+static int is_lane = 0;
+
/*
* These are offsets for the ATM pseudo-header.
*/
static u_int off_proto;
/*
- * This is the offset to the message type for Q.2931 messages.
+ * This is the offset of the first byte after the ATM pseudo_header,
+ * or -1 if there is no ATM pseudo-header.
*/
-static u_int off_msg_type;
+static u_int off_payload;
/*
* These are offsets to the beginning of the network-layer header.
/*
* Assume it's not raw ATM with a pseudo-header, for now.
*/
+ off_mac = 0;
is_atm = 0;
+ is_lane = 0;
off_vpi = -1;
off_vci = -1;
off_proto = -1;
- off_msg_type = -1;
+ off_payload = -1;
orig_linktype = -1;
orig_nl = -1;
* pseudo-header.
*/
is_atm = 1;
- off_linktype = SUNATM_PKT_BEGIN_POS;
off_vpi = SUNATM_VPI_POS;
off_vci = SUNATM_VCI_POS;
off_proto = PROTO_POS;
- off_msg_type = SUNATM_PKT_BEGIN_POS+MSG_TYPE_POS;
- off_nl = SUNATM_PKT_BEGIN_POS+8; /* 802.2+SNAP */
- off_nl_nosnap = SUNATM_PKT_BEGIN_POS+3; /* 802.2 */
+ off_mac = -1; /* LLC-encapsulated, so no MAC-layer header */
+ off_payload = SUNATM_PKT_BEGIN_POS;
+ off_linktype = off_payload;
+ off_nl = off_payload+8; /* 802.2+SNAP */
+ off_nl_nosnap = off_payload+3; /* 802.2 */
return;
case DLT_RAW:
((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
static struct block *
-gen_linktype(proto)
+gen_ether_linktype(proto)
register int proto;
{
- struct block *b0, *b1, *b2;
+ struct block *b0, *b1;
- switch (linktype) {
+ switch (proto) {
- case DLT_EN10MB:
- switch (proto) {
+ case LLCSAP_ISONS:
+ /*
+ * OSI protocols always use 802.2 encapsulation.
+ * XXX - should we check both the DSAP and the
+ * SSAP, like this, or should we check just the
+ * DSAP?
+ */
+ b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU);
+ gen_not(b0);
+ b1 = gen_cmp(off_linktype + 2, BPF_H, (bpf_int32)
+ ((LLCSAP_ISONS << 8) | LLCSAP_ISONS));
+ gen_and(b0, b1);
+ return b1;
- case LLCSAP_ISONS:
- /*
- * OSI protocols always use 802.2 encapsulation.
- * XXX - should we check both the DSAP and the
- * SSAP, like this, or should we check just the
- * DSAP?
- */
- b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU);
- gen_not(b0);
- b1 = gen_cmp(off_linktype + 2, BPF_H, (bpf_int32)
- ((LLCSAP_ISONS << 8) | LLCSAP_ISONS));
- gen_and(b0, b1);
- return b1;
+ case LLCSAP_NETBEUI:
+ /*
+ * NetBEUI always uses 802.2 encapsulation.
+ * XXX - should we check both the DSAP and the
+ * SSAP, like this, or should we check just the
+ * DSAP?
+ */
+ b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU);
+ gen_not(b0);
+ b1 = gen_cmp(off_linktype + 2, BPF_H, (bpf_int32)
+ ((LLCSAP_NETBEUI << 8) | LLCSAP_NETBEUI));
+ gen_and(b0, b1);
+ return b1;
- case LLCSAP_NETBEUI:
- /*
- * NetBEUI always uses 802.2 encapsulation.
- * XXX - should we check both the DSAP and the
- * SSAP, like this, or should we check just the
- * DSAP?
- */
- b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU);
- gen_not(b0);
- b1 = gen_cmp(off_linktype + 2, BPF_H, (bpf_int32)
- ((LLCSAP_NETBEUI << 8) | LLCSAP_NETBEUI));
- gen_and(b0, b1);
- return b1;
+ case LLCSAP_IPX:
+ /*
+ * Check for;
+ *
+ * Ethernet_II frames, which are Ethernet
+ * frames with a frame type of ETHERTYPE_IPX;
+ *
+ * Ethernet_802.3 frames, which are 802.3
+ * frames (i.e., the type/length field is
+ * a length field, <= ETHERMTU, rather than
+ * a type field) with the first two bytes
+ * after the Ethernet/802.3 header being
+ * 0xFFFF;
+ *
+ * Ethernet_802.2 frames, which are 802.3
+ * frames with an 802.2 LLC header and
+ * with the IPX LSAP as the DSAP in the LLC
+ * header;
+ *
+ * Ethernet_SNAP frames, which are 802.3
+ * frames with an LLC header and a SNAP
+ * header and with an OUI of 0x000000
+ * (encapsulated Ethernet) and a protocol
+ * ID of ETHERTYPE_IPX in the SNAP header.
+ *
+ * XXX - should we generate the same code both
+ * for tests for LLCSAP_IPX and for ETHERTYPE_IPX?
+ */
- case LLCSAP_IPX:
- /*
- * Check for;
- *
- * Ethernet_II frames, which are Ethernet
- * frames with a frame type of ETHERTYPE_IPX;
- *
- * Ethernet_802.3 frames, which are 802.3
- * frames (i.e., the type/length field is
- * a length field, <= ETHERMTU, rather than
- * a type field) with the first two bytes
- * after the Ethernet/802.3 header being
- * 0xFFFF;
- *
- * Ethernet_802.2 frames, which are 802.3
- * frames with an 802.2 LLC header and
- * with the IPX LSAP as the DSAP in the LLC
- * header;
- *
- * Ethernet_SNAP frames, which are 802.3
- * frames with an LLC header and a SNAP
- * header and with an OUI of 0x000000
- * (encapsulated Ethernet) and a protocol
- * ID of ETHERTYPE_IPX in the SNAP header.
- *
- * XXX - should we generate the same code both
- * for tests for LLCSAP_IPX and for ETHERTYPE_IPX?
- */
+ /*
+ * This generates code to check both for the
+ * IPX LSAP (Ethernet_802.2) and for Ethernet_802.3.
+ */
+ b0 = gen_cmp(off_linktype + 2, BPF_B, (bpf_int32)LLCSAP_IPX);
+ b1 = gen_cmp(off_linktype + 2, BPF_H, (bpf_int32)0xFFFF);
+ gen_or(b0, b1);
- /*
- * This generates code to check both for the
- * IPX LSAP (Ethernet_802.2) and for Ethernet_802.3.
- */
- b0 = gen_cmp(off_linktype + 2, BPF_B,
- (bpf_int32)LLCSAP_IPX);
- b1 = gen_cmp(off_linktype + 2, BPF_H,
- (bpf_int32)0xFFFF);
- gen_or(b0, b1);
+ /*
+ * Now we add code to check for SNAP frames with
+ * ETHERTYPE_IPX, i.e. Ethernet_SNAP.
+ */
+ b0 = gen_snap(0x000000, ETHERTYPE_IPX, 14);
+ gen_or(b0, b1);
- /*
- * Now we add code to check for SNAP frames with
- * ETHERTYPE_IPX, i.e. Ethernet_SNAP.
- */
- b0 = gen_snap(0x000000, ETHERTYPE_IPX, 14);
- gen_or(b0, b1);
+ /*
+ * Now we generate code to check for 802.3
+ * frames in general.
+ */
+ b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU);
+ gen_not(b0);
- /*
- * Now we generate code to check for 802.3
- * frames in general.
- */
- b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU);
- gen_not(b0);
+ /*
+ * Now add the check for 802.3 frames before the
+ * check for Ethernet_802.2 and Ethernet_802.3,
+ * as those checks should only be done on 802.3
+ * frames, not on Ethernet frames.
+ */
+ gen_and(b0, b1);
- /*
- * Now add the check for 802.3 frames before the
- * check for Ethernet_802.2 and Ethernet_802.3,
- * as those checks should only be done on 802.3
- * frames, not on Ethernet frames.
- */
- gen_and(b0, b1);
+ /*
+ * Now add the check for Ethernet_II frames, and
+ * do that before checking for the other frame
+ * types.
+ */
+ b0 = gen_cmp(off_linktype, BPF_H, (bpf_int32)ETHERTYPE_IPX);
+ gen_or(b0, b1);
+ return b1;
- /*
- * Now add the check for Ethernet_II frames, and
- * do that before checking for the other frame
- * types.
- */
- b0 = gen_cmp(off_linktype, BPF_H,
- (bpf_int32)ETHERTYPE_IPX);
- gen_or(b0, b1);
- return b1;
+ case ETHERTYPE_ATALK:
+ case ETHERTYPE_AARP:
+ /*
+ * EtherTalk (AppleTalk protocols on Ethernet link
+ * layer) may use 802.2 encapsulation.
+ */
- case ETHERTYPE_ATALK:
- case ETHERTYPE_AARP:
- /*
- * EtherTalk (AppleTalk protocols on Ethernet link
- * layer) may use 802.2 encapsulation.
- */
+ /*
+ * Check for 802.2 encapsulation (EtherTalk phase 2?);
+ * we check for an Ethernet type field less than
+ * 1500, which means it's an 802.3 length field.
+ */
+ b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU);
+ gen_not(b0);
+
+ /*
+ * 802.2-encapsulated ETHERTYPE_ATALK packets are
+ * SNAP packets with an organization code of
+ * 0x080007 (Apple, for Appletalk) and a protocol
+ * type of ETHERTYPE_ATALK (Appletalk).
+ *
+ * 802.2-encapsulated ETHERTYPE_AARP packets are
+ * SNAP packets with an organization code of
+ * 0x000000 (encapsulated Ethernet) and a protocol
+ * type of ETHERTYPE_AARP (Appletalk ARP).
+ */
+ if (proto == ETHERTYPE_ATALK)
+ b1 = gen_snap(0x080007, ETHERTYPE_ATALK, 14);
+ else /* proto == ETHERTYPE_AARP */
+ b1 = gen_snap(0x000000, ETHERTYPE_AARP, 14);
+ gen_and(b0, b1);
+
+ /*
+ * Check for Ethernet encapsulation (Ethertalk
+ * phase 1?); we just check for the Ethernet
+ * protocol type.
+ */
+ b0 = gen_cmp(off_linktype, BPF_H, (bpf_int32)proto);
+ gen_or(b0, b1);
+ return b1;
+
+ default:
+ if (proto <= ETHERMTU) {
/*
- * Check for 802.2 encapsulation (EtherTalk phase 2?);
- * we check for an Ethernet type field less than
- * 1500, which means it's an 802.3 length field.
+ * This is an LLC SAP value, so the frames
+ * that match would be 802.2 frames.
+ * Check that the frame is an 802.2 frame
+ * (i.e., that the length/type field is
+ * a length field, <= ETHERMTU) and
+ * then check the DSAP.
*/
b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU);
gen_not(b0);
-
- /*
- * 802.2-encapsulated ETHERTYPE_ATALK packets are
- * SNAP packets with an organization code of
- * 0x080007 (Apple, for Appletalk) and a protocol
- * type of ETHERTYPE_ATALK (Appletalk).
- *
- * 802.2-encapsulated ETHERTYPE_AARP packets are
- * SNAP packets with an organization code of
- * 0x000000 (encapsulated Ethernet) and a protocol
- * type of ETHERTYPE_AARP (Appletalk ARP).
- */
- if (proto == ETHERTYPE_ATALK)
- b1 = gen_snap(0x080007, ETHERTYPE_ATALK, 14);
- else /* proto == ETHERTYPE_AARP */
- b1 = gen_snap(0x000000, ETHERTYPE_AARP, 14);
+ b1 = gen_cmp(off_linktype + 2, BPF_B, (bpf_int32)proto);
gen_and(b0, b1);
-
+ return b1;
+ } else {
/*
- * Check for Ethernet encapsulation (Ethertalk
- * phase 1?); we just check for the Ethernet
- * protocol type.
+ * This is an Ethernet type, so compare
+ * the length/type field with it (if
+ * the frame is an 802.2 frame, the length
+ * field will be <= ETHERMTU, and, as
+ * "proto" is > ETHERMTU, this test
+ * will fail and the frame won't match,
+ * which is what we want).
*/
- b0 = gen_cmp(off_linktype, BPF_H, (bpf_int32)proto);
+ return gen_cmp(off_linktype, BPF_H, (bpf_int32)proto);
+ }
+ }
+}
- gen_or(b0, b1);
- return b1;
+static struct block *
+gen_linktype(proto)
+ register int proto;
+{
+ struct block *b0, *b1, *b2;
- default:
- if (proto <= ETHERMTU) {
- /*
- * This is an LLC SAP value, so the frames
- * that match would be 802.2 frames.
- * Check that the frame is an 802.2 frame
- * (i.e., that the length/type field is
- * a length field, <= ETHERMTU) and
- * then check the DSAP.
- */
- b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU);
- gen_not(b0);
- b1 = gen_cmp(off_linktype + 2, BPF_B,
- (bpf_int32)proto);
- gen_and(b0, b1);
- return b1;
- } else {
- /*
- * This is an Ethernet type, so compare
- * the length/type field with it (if
- * the frame is an 802.2 frame, the length
- * field will be <= ETHERMTU, and, as
- * "proto" is > ETHERMTU, this test
- * will fail and the frame won't match,
- * which is what we want).
- */
- return gen_cmp(off_linktype, BPF_H,
- (bpf_int32)proto);
- }
- }
+ switch (linktype) {
+
+ case DLT_EN10MB:
+ return gen_ether_linktype(proto);
break;
case DLT_IEEE802_11:
case DLT_SUNATM:
/*
- * Check for LLC encapsulation and then check the protocol.
- * XXX - also check for LANE and then check for an Ethernet
- * type?
+ * If "is_lane" is set, check for a LANE-encapsulated
+ * version of this protocol, otherwise check for an
+ * LLC-encapsulated version of this protocol.
+ *
+ * We assume LANE means Ethernet, not Token Ring.
*/
- b0 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
- b1 = gen_llc(proto);
- gen_and(b0, b1);
- return b1;
+ if (is_lane) {
+ /*
+ * Check that the packet doesn't begin with an
+ * LE Control marker. (We've already generated
+ * a test for LANE.)
+ */
+ b0 = gen_cmp(SUNATM_PKT_BEGIN_POS, BPF_H, 0xFF00);
+ gen_not(b0);
+
+ /*
+ * Now generate an Ethernet test.
+ */
+ b1 = gen_ether_linktype(proto);
+ gen_and(b0, b1);
+ return b1;
+ } else {
+ /*
+ * Check for LLC encapsulation and then check the
+ * protocol.
+ */
+ b0 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
+ b1 = gen_llc(proto);
+ gen_and(b0, b1);
+ return b1;
+ }
case DLT_LINUX_SLL:
switch (proto) {
snapblock[0] = LLCSAP_SNAP; /* DSAP = SNAP */
snapblock[1] = LLCSAP_SNAP; /* SSAP = SNAP */
- snapblock[2] = 0x03; /* control = UI */
+ snapblock[2] = 0x03; /* control = UI */
snapblock[3] = (orgcode >> 16); /* upper 8 bits of organization code */
snapblock[4] = (orgcode >> 8); /* middle 8 bits of organization code */
snapblock[5] = (orgcode >> 0); /* lower 8 bits of organization code */
switch (dir) {
case Q_SRC:
- return gen_bcmp(6, 6, eaddr);
+ return gen_bcmp(off_mac + 6, 6, eaddr);
case Q_DST:
- return gen_bcmp(0, 6, eaddr);
+ return gen_bcmp(off_mac + 0, 6, eaddr);
case Q_AND:
b0 = gen_ehostop(eaddr, Q_SRC);
b0 = gen_thostop(eaddr, Q_OR);
else if (linktype == DLT_IEEE802_11)
b0 = gen_wlanhostop(eaddr, Q_OR);
- else
+ else if (linktype == DLT_SUNATM && is_lane) {
+ /*
+ * Check that the packet doesn't begin with an
+ * LE Control marker. (We've already generated
+ * a test for LANE.)
+ */
+ b1 = gen_cmp(SUNATM_PKT_BEGIN_POS, BPF_H, 0xFF00);
+ gen_not(b1);
+
+ /*
+ * Now check the MAC address.
+ */
+ b0 = gen_ehostop(eaddr, Q_OR);
+ gen_and(b1, b0);
+ } else
bpf_error(
"'gateway' supported only on ethernet/FDDI/token ring/802.11");
free(eaddr);
return b;
- default:
- bpf_error(
- "only ethernet/FDDI/token ring/802.11 supports link-level host name");
- break;
+ case DLT_SUNATM:
+ if (!is_lane)
+ break;
+
+ /*
+ * Check that the packet doesn't begin
+ * with an LE Control marker. (We've
+ * already generated a test for LANE.)
+ */
+ tmp = gen_cmp(SUNATM_PKT_BEGIN_POS, BPF_H,
+ 0xFF00);
+ gen_not(tmp);
+
+ eaddr = pcap_ether_hostton(name);
+ if (eaddr == NULL)
+ bpf_error(
+ "unknown ether host '%s'", name);
+ b = gen_ehostop(eaddr, dir);
+ gen_and(tmp, b);
+ free(eaddr);
+ return b;
}
+
+ bpf_error("only ethernet/FDDI/token ring/802.11/ATM LANE supports link-level host name");
} else if (proto == Q_DECNET) {
unsigned short dn_addr = __pcap_nametodnaddr(name);
/*
register const u_char *eaddr;
struct qual q;
{
+ struct block *b, *tmp;
+
if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK) {
if (linktype == DLT_EN10MB)
return gen_ehostop(eaddr, (int)q.dir);
return gen_thostop(eaddr, (int)q.dir);
if (linktype == DLT_IEEE802_11)
return gen_wlanhostop(eaddr, (int)q.dir);
- bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11");
+ if (linktype == DLT_SUNATM && 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(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;
+ }
+ bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE");
}
bpf_error("ethernet address used in non-ether expression");
/* NOTREACHED */
bpf_error("unsupported index operation");
case Q_LINK:
+ /*
+ * XXX - what about ATM LANE? Should the index be
+ * relative to the beginning of the AAL5 frame, so
+ * that 0 refers to the beginning of the LE Control
+ * field, or relative to the beginning of the LAN
+ * frame, so that 0 refers, for Ethernet LANE, to
+ * the beginning of the destination address?
+ */
s = xfer_to_x(index);
tmp = new_stmt(BPF_LD|BPF_IND|size);
sappend(s, tmp);
return gen_thostop(ebroadcast, Q_DST);
if (linktype == DLT_IEEE802_11)
return gen_wlanhostop(ebroadcast, Q_DST);
+ if (linktype == DLT_SUNATM && is_lane) {
+ /*
+ * Check that the packet doesn't begin with an
+ * LE Control marker. (We've already generated
+ * a test for LANE.)
+ */
+ b1 = gen_cmp(SUNATM_PKT_BEGIN_POS, BPF_H, 0xFF00);
+ gen_not(b1);
+
+ /*
+ * Now check the MAC address.
+ */
+ b0 = gen_ehostop(ebroadcast, Q_DST);
+ gen_and(b1, b0);
+ return b0;
+ }
bpf_error("not a broadcast link");
break;
return b0;
}
+ if (linktype == DLT_SUNATM && is_lane) {
+ /*
+ * Check that the packet doesn't begin with an
+ * LE Control marker. (We've already generated
+ * a test for LANE.)
+ */
+ b1 = gen_cmp(SUNATM_PKT_BEGIN_POS, BPF_H, 0xFF00);
+ gen_not(b1);
+
+ /* ether[off_mac] & 1 != 0 */
+ b0 = gen_mac_multicast(off_mac);
+ gen_and(b1, b0);
+ return b0;
+ }
+
/* Link not known to support multicasts */
break;
break;
case A_MSGTYPE:
- if (off_msg_type == -1)
+ if (off_payload == -1)
abort();
- b0 = gen_ncmp(BPF_B, off_msg_type, 0xffffffff,
+ b0 = gen_ncmp(BPF_B, off_payload + MSG_TYPE_POS, 0xffffffff,
(u_int)jtype, (u_int)jvalue, reverse);
break;
if (!is_atm)
bpf_error("'lane' supported only on raw ATM");
b1 = gen_atmfield_code(A_PROTOTYPE, PT_LANE, BPF_JEQ, 0);
+
+ /*
+ * Arrange that all subsequent tests assume LANE
+ * rather than LLC-encapsulated packets, and set
+ * the offsets appropriately for LANE-encapsulated
+ * Ethernet.
+ *
+ * "off_mac" is the offset of the Ethernet header,
+ * which is 2 bytes past the ATM pseudo-header
+ * (skipping the pseudo-header and 2-byte LE Client
+ * field). The other offsets are Ethernet offsets
+ * relative to "off_mac".
+ */
+ is_lane = 1;
+ off_mac = off_payload + 2; /* MAC header */
+ off_linktype = off_mac + 12;
+ off_nl = off_mac + 14; /* Ethernet II */
+ off_nl_nosnap = off_mac + 17; /* 802.3+802.2 */
break;
case A_LLC:
if (!is_atm)
bpf_error("'llc' supported only on raw ATM");
b1 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
+ is_lane = 0;
break;
default:
projects / libpcap / commitdiff
