*/
#ifndef lint
static const char rcsid[] _U_ =
- "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.12 2005-05-01 08:37:48 guy Exp $ (LBL)";
+ "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.41 2006-09-13 07:02:15 guy Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
static jmp_buf top_ctx;
static pcap_t *bpf_pcap;
-/* Hack for updating VLAN, MPLS offsets. */
-static u_int orig_linktype = -1U, orig_nl = -1U;
+/* Hack for updating VLAN, MPLS, and PPPoE offsets. */
+static u_int orig_linktype = -1U, orig_nl = -1U, label_stack_depth = -1U;
/* XXX */
#ifdef PCAP_FDDIPAD
* is relative to.
*/
enum e_offrel {
+ OR_PACKET, /* relative to the beginning of the packet */
OR_LINK, /* relative to the link-layer header */
OR_NET, /* relative to the network-layer header */
OR_NET_NOSNAP, /* relative to the network-layer header, with no SNAP header at the link layer */
static struct block *gen_bcmp(enum e_offrel, u_int, u_int, const u_char *);
static struct block *gen_ncmp(enum e_offrel, bpf_u_int32, bpf_u_int32,
bpf_u_int32, bpf_u_int32, int, bpf_int32);
+static struct slist *gen_load_llrel(u_int, u_int);
static struct slist *gen_load_a(enum e_offrel, u_int, u_int);
+static struct slist *gen_loadx_iphdrlen(void);
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_linux_sll_linktype(int);
+static void insert_radiotap_load_llprefixlen(struct block *);
+static void insert_load_llprefixlen(struct block *);
+static struct slist *gen_llprefixlen(void);
static struct block *gen_linktype(int);
static struct block *gen_snap(bpf_u_int32, bpf_u_int32, u_int);
static struct block *gen_llc_linktype(int);
static struct block *gen_wlanhostop(const u_char *, int);
static struct block *gen_ipfchostop(const u_char *, int);
static struct block *gen_dnhostop(bpf_u_int32, int);
-static struct block *gen_host(bpf_u_int32, bpf_u_int32, int, int);
+static struct block *gen_mpls_linktype(int);
+static struct block *gen_host(bpf_u_int32, bpf_u_int32, int, int, int);
#ifdef INET6
-static struct block *gen_host6(struct in6_addr *, struct in6_addr *, int, int);
+static struct block *gen_host6(struct in6_addr *, struct in6_addr *, int, int, int);
#endif
#ifndef INET6
static struct block *gen_gateway(const u_char *, bpf_u_int32 **, int, int);
p->sense = !p->sense;
backpatch(p, gen_retblk(0));
root = p->head;
+
+ /*
+ * Insert before the statements of the first (root) block any
+ * statements needed to load the lengths of any variable-length
+ * headers into registers.
+ *
+ * XXX - a fancier strategy would be to insert those before the
+ * statements of all blocks that use those lengths and that
+ * have no predecessors that use them, so that we only compute
+ * the lengths if we need them. There might be even better
+ * approaches than that. However, as we're currently only
+ * handling variable-length radiotap headers, and as all
+ * filtering expressions other than raw link[M:N] tests
+ * require the length of that header, doing more for that
+ * header length isn't really worth the effort.
+ */
+ insert_load_llprefixlen(root);
}
void
/*
* Various code constructs need to know the layout of the data link
- * layer. These variables give the necessary offsets.
+ * layer. These variables give the necessary offsets from the beginning
+ * of the packet data.
+ *
+ * If the link layer has variable_length headers, the offsets are offsets
+ * from the end of the link-link-layer header, and "reg_ll_size" is
+ * the register number for a register containing the length of the
+ * link-layer header. Otherwise, "reg_ll_size" is -1.
+ */
+static int reg_ll_size;
+
+/*
+ * This is the offset of the beginning of the link-layer header from
+ * the beginning of the raw packet data.
+ *
+ * It's usually 0, except for 802.11 with a fixed-length radio header.
+ * (For 802.11 with a variable-length radio header, we have to generate
+ * code to compute that offset; off_ll is 0 in that case.)
*/
+static u_int off_ll;
/*
* This is the offset of the beginning of the MAC-layer header.
- * It's usually 0, except for ATM LANE.
+ * It's usually 0, except for ATM LANE, where it's the offset, relative
+ * to the beginning of the raw packet data, of the Ethernet header.
*/
static u_int off_mac;
/*
* "off_linktype" is the offset to information in the link-layer header
- * giving the packet type.
+ * giving the packet type. This offset is relative to the beginning
+ * of the link-layer header (i.e., it doesn't include off_ll).
*
* For Ethernet, it's the offset of the Ethernet type field.
*
static u_int off_vci;
static u_int off_proto;
+/*
+ * These are offsets for the MTP3 fields.
+ */
+static u_int off_sio;
+static u_int off_opc;
+static u_int off_dpc;
+static u_int off_sls;
+
/*
* This is the offset of the first byte after the ATM pseudo_header,
* or -1 if there is no ATM pseudo-header.
/*
* These are offsets to the beginning of the network-layer header.
+ * They are relative to the beginning of the link-layer header (i.e.,
+ * they don't include off_ll).
*
* If the link layer never uses 802.2 LLC:
*
off_proto = -1;
off_payload = -1;
+ /*
+ * And assume we're not doing SS7.
+ */
+ off_sio = -1;
+ off_opc = -1;
+ off_dpc = -1;
+ off_sls = -1;
+
+ /*
+ * Also assume it's not 802.11 with a fixed-length radio header.
+ */
+ off_ll = 0;
+
orig_linktype = -1;
orig_nl = -1;
+ label_stack_depth = 0;
+
+ reg_ll_size = -1;
switch (linktype) {
* XXX - same variable-length header problem; at least
* the Prism header is fixed-length.
*/
- off_linktype = 144+24;
- off_nl = 144+32; /* Prism+802.11+802.2+SNAP */
- off_nl_nosnap = 144+27; /* Prism+802.11+802.2 */
+ off_ll = 144;
+ off_linktype = 24;
+ off_nl = 32; /* Prism+802.11+802.2+SNAP */
+ off_nl_nosnap = 27; /* Prism+802.11+802.2 */
return;
case DLT_IEEE802_11_RADIO_AVS:
* more so; this header is also variable-length,
* with the length being the 32-bit big-endian
* number at an offset of 4 from the beginning
- * of the radio header.
+ * of the radio header. We should handle that the
+ * same way we handle the length at the beginning
+ * of the radiotap header.
+ *
+ * XXX - in Linux, do any drivers that supply an AVS
+ * header supply a link-layer type other than
+ * ARPHRD_IEEE80211_PRISM? If so, we should map that
+ * to DLT_IEEE802_11_RADIO_AVS; if not, or if there are
+ * any drivers that supply an AVS header but supply
+ * an ARPHRD value of ARPHRD_IEEE80211_PRISM, we'll
+ * have to check the header in the generated code to
+ * determine whether it's Prism or AVS.
*/
- off_linktype = 64+24;
- off_nl = 64+32; /* Radio+802.11+802.2+SNAP */
- off_nl_nosnap = 64+27; /* Radio+802.11+802.2 */
+ off_ll = 64;
+ off_linktype = 24;
+ off_nl = 32; /* Radio+802.11+802.2+SNAP */
+ off_nl_nosnap = 27; /* Radio+802.11+802.2 */
return;
case DLT_IEEE802_11_RADIO:
* the 802.11 header, containing a bunch of additional
* information including radio-level information.
*
- * XXX - same variable-length header problem, only
- * even *more* so; this header is also variable-length,
- * with the length being the 16-bit number at an offset
- * of 2 from the beginning of the radio header, and it's
- * device-dependent (different devices might supply
- * different amounts of information), so we can't even
- * assume a fixed length for the current version of the
- * header.
- *
- * Therefore, currently, only raw "link[N:M]" filtering is
- * supported.
+ * The radiotap header is variable length, and we
+ * generate code to compute its length and store it
+ * in a register. These offsets are relative to the
+ * beginning of the 802.11 header.
*/
- off_linktype = -1;
- off_nl = -1;
- off_nl_nosnap = -1;
+ off_linktype = 24;
+ off_nl = 32; /* 802.11+802.2+SNAP */
+ off_nl_nosnap = 27; /* 802.11+802.2 */
return;
case DLT_ATM_RFC1483:
/*
* assume routed, non-ISO PDUs
* (i.e., LLC = 0xAA-AA-03, OUT = 0x00-00-00)
+ *
+ * XXX - what about ISO PDUs, e.g. CLNP, ISIS, ESIS,
+ * or PPP with the PPP NLPID (e.g., PPPoA)? The
+ * latter would presumably be treated the way PPPoE
+ * should be, so you can do "pppoe and udp port 2049"
+ * or "pppoa and tcp port 80" and have it check for
+ * PPPo{A,E} and a PPP protocol of IP and....
*/
off_linktype = 0;
off_nl = 8; /* 802.2+SNAP */
off_nl_nosnap = 0; /* no 802.2 LLC */
return;
+ /*
+ * the only BPF-interesting FRF.16 frames are non-control frames;
+ * Frame Relay has a variable length link-layer
+ * so lets start with offset 4 for now and increments later on (FIXME);
+ */
+ case DLT_MFR:
+ off_linktype = -1;
+ off_nl = 4;
+ off_nl_nosnap = 0; /* XXX - for now -> no 802.2 LLC */
+ return;
+
case DLT_APPLE_IP_OVER_IEEE1394:
off_linktype = 16;
off_nl = 18;
off_nl_nosnap = PFLOG_HDRLEN; /* no 802.2 LLC */
return;
+ case DLT_JUNIPER_MFR:
case DLT_JUNIPER_MLFR:
case DLT_JUNIPER_MLPPP:
+ case DLT_JUNIPER_PPP:
+ case DLT_JUNIPER_CHDLC:
+ case DLT_JUNIPER_FRELAY:
off_linktype = 4;
off_nl = 4;
off_nl_nosnap = -1; /* no 802.2 LLC */
off_nl_nosnap = 18;
return;
+ /* frames captured on a Juniper PPPoE service PIC
+ * contain raw ethernet frames */
+ case DLT_JUNIPER_PPPOE:
+ case DLT_JUNIPER_ETHER:
+ off_linktype = 16;
+ off_nl = 18; /* Ethernet II */
+ off_nl_nosnap = 21; /* 802.3+802.2 */
+ return;
+
+ case DLT_JUNIPER_PPPOE_ATM:
+ off_linktype = 4;
+ off_nl = 6;
+ off_nl_nosnap = -1; /* no 802.2 LLC */
+ return;
+
+ case DLT_JUNIPER_GGSN:
+ off_linktype = 6;
+ off_nl = 12;
+ off_nl_nosnap = -1; /* no 802.2 LLC */
+ return;
+
+ case DLT_JUNIPER_ES:
+ off_linktype = 6;
+ off_nl = -1; /* not really a network layer but raw IP adresses */
+ off_nl_nosnap = -1; /* no 802.2 LLC */
+ return;
+
+ case DLT_JUNIPER_MONITOR:
+ off_linktype = 12;
+ off_nl = 12; /* raw IP/IP6 header */
+ off_nl_nosnap = -1; /* no 802.2 LLC */
+ return;
+
+ case DLT_JUNIPER_SERVICES:
+ off_linktype = 12;
+ off_nl = -1; /* L3 proto location dep. on cookie type */
+ off_nl_nosnap = -1; /* no 802.2 LLC */
+ return;
+
+ case DLT_MTP2:
+ off_sio = 3;
+ off_opc = 4;
+ off_dpc = 4;
+ off_sls = 7;
+ off_linktype = -1;
+ off_nl = -1;
+ off_nl_nosnap = -1;
+ return;
+
#ifdef DLT_PFSYNC
case DLT_PFSYNC:
off_linktype = -1;
/* NOTREACHED */
}
+/*
+ * Load a value relative to the beginning of the link-layer header.
+ * The link-layer header doesn't necessarily begin at the beginning
+ * of the packet data; there might be a variable-length prefix containing
+ * radio information.
+ */
+static struct slist *
+gen_load_llrel(offset, size)
+ u_int offset, size;
+{
+ struct slist *s, *s2;
+
+ s = gen_llprefixlen();
+
+ /*
+ * If "s" is non-null, it has code to arrange that the X register
+ * contains the length of the prefix preceding the link-layer
+ * header.
+ *
+ * Otherwise, the length of the prefix preceding the link-layer
+ * header is "off_ll".
+ */
+ if (s != NULL) {
+ s2 = new_stmt(BPF_LD|BPF_IND|size);
+ s2->s.k = offset;
+ sappend(s, s2);
+ } else {
+ s = new_stmt(BPF_LD|BPF_ABS|size);
+ s->s.k = offset + off_ll;
+ }
+ return s;
+}
+
/*
* Load a value relative to the beginning of the specified header.
*/
enum e_offrel offrel;
u_int offset, size;
{
- struct slist *s;
+ struct slist *s, *s2;
switch (offrel) {
+ case OR_PACKET:
+ s = new_stmt(BPF_LD|BPF_ABS|size);
+ s->s.k = offset;
+ break;
+
case OR_LINK:
- s = new_stmt(BPF_LD|BPF_ABS|size);
- s->s.k = offset;
+ s = gen_load_llrel(offset, size);
break;
case OR_NET:
- s = new_stmt(BPF_LD|BPF_ABS|size);
- s->s.k = off_nl + offset;
+ s = gen_load_llrel(off_nl + offset, size);
break;
case OR_NET_NOSNAP:
- s = new_stmt(BPF_LD|BPF_ABS|size);
- s->s.k = off_nl_nosnap + offset;
+ s = gen_load_llrel(off_nl_nosnap + offset, size);
break;
case OR_TRAN_IPV4:
* Load the X register with the length of the IPv4 header,
* in bytes.
*/
- s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
- s->s.k = off_nl;
+ s = gen_loadx_iphdrlen();
/*
* Load the item at {length of the link-layer header} +
* {length of the IPv4 header} + {specified offset}.
*/
- s->next = new_stmt(BPF_LD|BPF_IND|size);
- s->next->s.k = off_nl + offset;
+ s2 = new_stmt(BPF_LD|BPF_IND|size);
+ s2->s.k = off_nl + offset;
+ sappend(s, s2);
break;
case OR_TRAN_IPV6:
- s = new_stmt(BPF_LD|BPF_ABS|size);
- s->s.k = off_nl + 40 + offset;
+ s = gen_load_llrel(off_nl + 40 + offset, size);
break;
default:
return s;
}
+/*
+ * Generate code to load into the X register the sum of the length of
+ * the IPv4 header and any variable-length header preceding the link-layer
+ * header.
+ */
+static struct slist *
+gen_loadx_iphdrlen()
+{
+ struct slist *s, *s2;
+
+ s = gen_llprefixlen();
+ if (s != NULL) {
+ /*
+ * There's a variable-length prefix preceding the
+ * link-layer header. "s" points to a list of statements
+ * that put the length of that prefix into the X register.
+ * The 4*([k]&0xf) addressing mode can't be used, as we
+ * don't have a constant offset, so we have to load the
+ * value in question into the A register and add to it
+ * the value from the X register.
+ */
+ s2 = new_stmt(BPF_LD|BPF_IND|BPF_B);
+ s2->s.k = off_nl;
+ sappend(s, s2);
+ s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
+ s2->s.k = 0xf;
+ sappend(s, s2);
+ s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
+ s2->s.k = 2;
+ sappend(s, s2);
+
+ /*
+ * The A register now contains the length of the
+ * IP header. We need to add to it the length
+ * of the prefix preceding the link-layer
+ * header, which is still in the X register, and
+ * move the result into the X register.
+ */
+ sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
+ sappend(s, new_stmt(BPF_MISC|BPF_TAX));
+ } else {
+ /*
+ * There is no variable-length header preceding the
+ * link-layer header; if there's a fixed-length
+ * header preceding it, its length is included in
+ * the off_ variables, so it doesn't need to be added.
+ */
+ s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
+ s->s.k = off_nl;
+ }
+ return s;
+}
+
static struct block *
gen_uncond(rsense)
int rsense;
}
}
+static void
+insert_radiotap_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)
+ struct block *b;
+{
+ switch (linktype) {
+
+ case DLT_IEEE802_11_RADIO:
+ insert_radiotap_load_llprefixlen(b);
+ }
+}
+
+
+static struct slist *
+gen_radiotap_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
+ * "struct slist" for the list of statements in that code, or NULL if
+ * no code is necessary.
+ */
+static struct slist *
+gen_llprefixlen(void)
+{
+ switch (linktype) {
+
+ case DLT_IEEE802_11_RADIO:
+ return gen_radiotap_llprefixlen();
+
+ default:
+ return NULL;
+ }
+}
+
/*
* Generate code to match a particular packet type by matching the
* link-layer type field or fields in the 802.2 LLC header.
{
struct block *b0, *b1, *b2;
+ /* are we checking MPLS-encapsulated packets? */
+ if (label_stack_depth > 0) {
+ switch (proto) {
+ case ETHERTYPE_IP:
+ case PPP_IP:
+ /* FIXME add other L3 proto IDs */
+ return gen_mpls_linktype(Q_IP);
+
+ case ETHERTYPE_IPV6:
+ case PPP_IPV6:
+ /* FIXME add other L3 proto IDs */
+ return gen_mpls_linktype(Q_IPV6);
+
+ default:
+ bpf_error("unsupported protocol over mpls");
+ /* NOTREACHED */
+ }
+ }
+
switch (linktype) {
case DLT_EN10MB:
}
break;
- case DLT_IEEE802_11:
- case DLT_PRISM_HEADER:
- case DLT_IEEE802_11_RADIO:
case DLT_FDDI:
case DLT_IEEE802:
+ case DLT_IEEE802_11:
+ case DLT_IEEE802_11_RADIO_AVS:
+ case DLT_IEEE802_11_RADIO:
+ case DLT_PRISM_HEADER:
case DLT_ATM_RFC1483:
case DLT_ATM_CLIP:
case DLT_IP_OVER_FC:
/*NOTREACHED*/
break;
+ case DLT_JUNIPER_MFR:
case DLT_JUNIPER_MLFR:
case DLT_JUNIPER_MLPPP:
case DLT_JUNIPER_ATM1:
case DLT_JUNIPER_ATM2:
+ case DLT_JUNIPER_PPPOE:
+ case DLT_JUNIPER_PPPOE_ATM:
+ case DLT_JUNIPER_GGSN:
+ case DLT_JUNIPER_ES:
+ case DLT_JUNIPER_MONITOR:
+ case DLT_JUNIPER_SERVICES:
+ case DLT_JUNIPER_ETHER:
+ case DLT_JUNIPER_PPP:
+ case DLT_JUNIPER_FRELAY:
+ case DLT_JUNIPER_CHDLC:
/* just lets verify the magic number for now -
* on ATM we may have up to 6 different encapsulations on the wire
* and need a lot of heuristics to figure out that the payload
return b1;
}
+/*
+ * Generate a check for IPv4 or IPv6 for MPLS-encapsulated packets;
+ * test the bottom-of-stack bit, and then check the version number
+ * field in the IP header.
+ */
static struct block *
-gen_host(addr, mask, proto, dir)
+gen_mpls_linktype(proto)
+ int proto;
+{
+ struct block *b0, *b1;
+
+ switch (proto) {
+
+ case Q_IP:
+ /* match the bottom-of-stack bit */
+ b0 = gen_mcmp(OR_NET, -2, BPF_B, 0x01, 0x01);
+ /* match the IPv4 version number */
+ b1 = gen_mcmp(OR_NET, 0, BPF_B, 0x40, 0xf0);
+ gen_and(b0, b1);
+ return b1;
+
+ case Q_IPV6:
+ /* match the bottom-of-stack bit */
+ b0 = gen_mcmp(OR_NET, -2, BPF_B, 0x01, 0x01);
+ /* match the IPv4 version number */
+ b1 = gen_mcmp(OR_NET, 0, BPF_B, 0x60, 0xf0);
+ gen_and(b0, b1);
+ return b1;
+
+ default:
+ abort();
+ }
+}
+
+static struct block *
+gen_host(addr, mask, proto, dir, type)
bpf_u_int32 addr;
bpf_u_int32 mask;
int proto;
int dir;
+ int type;
{
struct block *b0, *b1;
+ const char *typestr;
+
+ if (type == Q_NET)
+ typestr = "net";
+ else
+ typestr = "host";
switch (proto) {
case Q_DEFAULT:
- b0 = gen_host(addr, mask, Q_IP, dir);
- if (off_linktype != (u_int)-1) {
- b1 = gen_host(addr, mask, Q_ARP, dir);
- gen_or(b0, b1);
- b0 = gen_host(addr, mask, Q_RARP, dir);
- gen_or(b1, b0);
+ b0 = gen_host(addr, mask, Q_IP, dir, type);
+ /*
+ * Only check for non-IPv4 addresses if we're not
+ * checking MPLS-encapsulated packets.
+ */
+ if (label_stack_depth == 0) {
+ b1 = gen_host(addr, mask, Q_ARP, dir, type);
+ gen_or(b0, b1);
+ b0 = gen_host(addr, mask, Q_RARP, dir, type);
+ gen_or(b1, b0);
}
return b0;
return gen_hostop(addr, mask, dir, ETHERTYPE_ARP, 14, 24);
case Q_TCP:
- bpf_error("'tcp' modifier applied to host");
+ bpf_error("'tcp' modifier applied to %s", typestr);
case Q_SCTP:
- bpf_error("'sctp' modifier applied to host");
+ bpf_error("'sctp' modifier applied to %s", typestr);
case Q_UDP:
- bpf_error("'udp' modifier applied to host");
+ bpf_error("'udp' modifier applied to %s", typestr);
case Q_ICMP:
- bpf_error("'icmp' modifier applied to host");
+ bpf_error("'icmp' modifier applied to %s", typestr);
case Q_IGMP:
- bpf_error("'igmp' modifier applied to host");
+ bpf_error("'igmp' modifier applied to %s", typestr);
case Q_IGRP:
- bpf_error("'igrp' modifier applied to host");
+ bpf_error("'igrp' modifier applied to %s", typestr);
case Q_PIM:
- bpf_error("'pim' modifier applied to host");
+ bpf_error("'pim' modifier applied to %s", typestr);
case Q_VRRP:
- bpf_error("'vrrp' modifier applied to host");
+ bpf_error("'vrrp' modifier applied to %s", typestr);
case Q_ATALK:
bpf_error("ATALK host filtering not implemented");
bpf_error("'ip6' modifier applied to ip host");
case Q_ICMPV6:
- bpf_error("'icmp6' modifier applied to host");
+ bpf_error("'icmp6' modifier applied to %s", typestr);
#endif /* INET6 */
case Q_AH:
- bpf_error("'ah' modifier applied to host");
+ bpf_error("'ah' modifier applied to %s", typestr);
case Q_ESP:
- bpf_error("'esp' modifier applied to host");
+ bpf_error("'esp' modifier applied to %s", typestr);
case Q_ISO:
bpf_error("ISO host filtering not implemented");
case Q_ESIS:
- bpf_error("'esis' modifier applied to host");
+ bpf_error("'esis' modifier applied to %s", typestr);
case Q_ISIS:
- bpf_error("'isis' modifier applied to host");
+ bpf_error("'isis' modifier applied to %s", typestr);
case Q_CLNP:
- bpf_error("'clnp' modifier applied to host");
+ bpf_error("'clnp' modifier applied to %s", typestr);
case Q_STP:
- bpf_error("'stp' modifier applied to host");
+ bpf_error("'stp' modifier applied to %s", typestr);
case Q_IPX:
bpf_error("IPX host filtering not implemented");
case Q_NETBEUI:
- bpf_error("'netbeui' modifier applied to host");
+ bpf_error("'netbeui' modifier applied to %s", typestr);
+
+ case Q_RADIO:
+ bpf_error("'radio' modifier applied to %s", typestr);
default:
abort();
#ifdef INET6
static struct block *
-gen_host6(addr, mask, proto, dir)
+gen_host6(addr, mask, proto, dir, type)
struct in6_addr *addr;
struct in6_addr *mask;
int proto;
int dir;
+ int type;
{
+ const char *typestr;
+
+ if (type == Q_NET)
+ typestr = "net";
+ else
+ typestr = "host";
+
switch (proto) {
case Q_DEFAULT:
- return gen_host6(addr, mask, Q_IPV6, dir);
+ return gen_host6(addr, mask, Q_IPV6, dir, type);
case Q_IP:
- bpf_error("'ip' modifier applied to ip6 host");
+ bpf_error("'ip' modifier applied to ip6 %s", typestr);
case Q_RARP:
- bpf_error("'rarp' modifier applied to ip6 host");
+ bpf_error("'rarp' modifier applied to ip6 %s", typestr);
case Q_ARP:
- bpf_error("'arp' modifier applied to ip6 host");
+ bpf_error("'arp' modifier applied to ip6 %s", typestr);
case Q_SCTP:
- bpf_error("'sctp' modifier applied to host");
+ bpf_error("'sctp' modifier applied to %s", typestr);
case Q_TCP:
- bpf_error("'tcp' modifier applied to host");
+ bpf_error("'tcp' modifier applied to %s", typestr);
case Q_UDP:
- bpf_error("'udp' modifier applied to host");
+ bpf_error("'udp' modifier applied to %s", typestr);
case Q_ICMP:
- bpf_error("'icmp' modifier applied to host");
+ bpf_error("'icmp' modifier applied to %s", typestr);
case Q_IGMP:
- bpf_error("'igmp' modifier applied to host");
+ bpf_error("'igmp' modifier applied to %s", typestr);
case Q_IGRP:
- bpf_error("'igrp' modifier applied to host");
+ bpf_error("'igrp' modifier applied to %s", typestr);
case Q_PIM:
- bpf_error("'pim' modifier applied to host");
+ bpf_error("'pim' modifier applied to %s", typestr);
case Q_VRRP:
- bpf_error("'vrrp' modifier applied to host");
+ bpf_error("'vrrp' modifier applied to %s", typestr);
case Q_ATALK:
bpf_error("ATALK host filtering not implemented");
bpf_error("AARP host filtering not implemented");
case Q_DECNET:
- bpf_error("'decnet' modifier applied to ip6 host");
+ bpf_error("'decnet' modifier applied to ip6 %s", typestr);
case Q_SCA:
bpf_error("SCA host filtering not implemented");
return gen_hostop6(addr, mask, dir, ETHERTYPE_IPV6, 8, 24);
case Q_ICMPV6:
- bpf_error("'icmp6' modifier applied to host");
+ bpf_error("'icmp6' modifier applied to %s", typestr);
case Q_AH:
- bpf_error("'ah' modifier applied to host");
+ bpf_error("'ah' modifier applied to %s", typestr);
case Q_ESP:
- bpf_error("'esp' modifier applied to host");
+ bpf_error("'esp' modifier applied to %s", typestr);
case Q_ISO:
bpf_error("ISO host filtering not implemented");
case Q_ESIS:
- bpf_error("'esis' modifier applied to host");
+ bpf_error("'esis' modifier applied to %s", typestr);
case Q_ISIS:
- bpf_error("'isis' modifier applied to host");
+ bpf_error("'isis' modifier applied to %s", typestr);
case Q_CLNP:
- bpf_error("'clnp' modifier applied to host");
+ bpf_error("'clnp' modifier applied to %s", typestr);
case Q_STP:
- bpf_error("'stp' modifier applied to host");
+ bpf_error("'stp' modifier applied to %s", typestr);
case Q_IPX:
bpf_error("IPX host filtering not implemented");
case Q_NETBEUI:
- bpf_error("'netbeui' modifier applied to host");
+ bpf_error("'netbeui' modifier applied to %s", typestr);
+
+ case Q_RADIO:
+ bpf_error("'radio' modifier applied to %s", typestr);
default:
abort();
case Q_IP:
case Q_ARP:
case Q_RARP:
- if (linktype == DLT_EN10MB)
- b0 = gen_ehostop(eaddr, Q_OR);
- else if (linktype == DLT_FDDI)
- b0 = gen_fhostop(eaddr, Q_OR);
- else if (linktype == DLT_IEEE802)
- b0 = gen_thostop(eaddr, Q_OR);
- else if (linktype == DLT_IEEE802_11)
- b0 = gen_wlanhostop(eaddr, Q_OR);
- else if (linktype == DLT_SUNATM && is_lane) {
+ switch (linktype) {
+ case DLT_EN10MB:
+ b0 = gen_ehostop(eaddr, Q_OR);
+ break;
+ case DLT_FDDI:
+ b0 = gen_fhostop(eaddr, Q_OR);
+ break;
+ case DLT_IEEE802:
+ b0 = gen_thostop(eaddr, Q_OR);
+ break;
+ case DLT_IEEE802_11:
+ case DLT_IEEE802_11_RADIO_AVS:
+ case DLT_IEEE802_11_RADIO:
+ case DLT_PRISM_HEADER:
+ b0 = gen_wlanhostop(eaddr, Q_OR);
+ break;
+ case DLT_SUNATM:
+ if (is_lane) {
/*
* Check that the packet doesn't begin with an
* LE Control marker. (We've already generated
*/
b0 = gen_ehostop(eaddr, Q_OR);
gen_and(b1, b0);
- } else if (linktype == DLT_IP_OVER_FC)
- b0 = gen_ipfchostop(eaddr, Q_OR);
- else
- bpf_error(
+ }
+ break;
+ case DLT_IP_OVER_FC:
+ b0 = gen_ipfchostop(eaddr, Q_OR);
+ break;
+ default:
+ bpf_error(
"'gateway' supported only on ethernet/FDDI/token ring/802.11/Fibre Channel");
-
- b1 = gen_host(**alist++, 0xffffffff, proto, Q_OR);
+ }
+ b1 = gen_host(**alist++, 0xffffffff, proto, Q_OR, Q_HOST);
while (*alist) {
- tmp = gen_host(**alist++, 0xffffffff, proto, Q_OR);
+ tmp = gen_host(**alist++, 0xffffffff, proto, Q_OR,
+ Q_HOST);
gen_or(b1, tmp);
b1 = tmp;
}
b1 = gen_linktype(LLCSAP_NETBEUI);
break;
+ case Q_RADIO:
+ bpf_error("'radio' is not a valid protocol type");
+
default:
abort();
}
return b;
}
+/*
+ * Generate a comparison to a port value in the transport-layer header
+ * at the specified offset from the beginning of that header.
+ *
+ * XXX - this handles a variable-length prefix preceding the link-layer
+ * header, such as the radiotap or AVS radio prefix, but doesn't handle
+ * variable-length link-layer headers (such as Token Ring or 802.11
+ * headers).
+ */
static struct block *
gen_portatom(off, v)
int off;
/*NOTREACHED*/
}
+ /*
+ * We don't handle variable-length radiotap here headers yet.
+ * We might want to add BPF instructions to do the protochain
+ * work, to simplify that and, on platforms that have a BPF
+ * interpreter with the new instructions, let the filtering
+ * be done in the kernel. (We already require a modified BPF
+ * engine to do the protochain stuff, to support backward
+ * branches, and backward branch support is unlikely to appear
+ * in kernel BPF engines.)
+ */
+ if (linktype == DLT_IEEE802_11_RADIO)
+ bpf_error("'protochain' not supported with radiotap headers");
+
no_optimize = 1; /*this code is not compatible with optimzer yet */
/*
*
* So we always check for ETHERTYPE_IP.
*/
+
b0 = gen_linktype(ETHERTYPE_IP);
#ifndef CHASE_CHAIN
b1 = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)v);
case Q_NETBEUI:
bpf_error("'netbeui proto' is bogus");
+ case Q_RADIO:
+ bpf_error("'radio proto' is bogus");
+
default:
abort();
/* NOTREACHED */
addr <<= 8;
mask <<= 8;
}
- return gen_host(addr, mask, proto, dir);
+ return gen_host(addr, mask, proto, dir, q.addr);
case Q_DEFAULT:
case Q_HOST:
return b;
case DLT_IEEE802_11:
+ case DLT_IEEE802_11_RADIO_AVS:
+ case DLT_IEEE802_11_RADIO:
+ case DLT_PRISM_HEADER:
eaddr = pcap_ether_hostton(name);
if (eaddr == NULL)
bpf_error(
* I don't think DECNET hosts can be multihomed, so
* there is no need to build up a list of addresses
*/
- return (gen_host(dn_addr, 0, proto, dir));
+ return (gen_host(dn_addr, 0, proto, dir, q.addr));
} else {
#ifndef INET6
alist = pcap_nametoaddr(name);
tproto = proto;
if (off_linktype == (u_int)-1 && tproto == Q_DEFAULT)
tproto = Q_IP;
- b = gen_host(**alist++, 0xffffffff, tproto, dir);
+ b = gen_host(**alist++, 0xffffffff, tproto, dir, q.addr);
while (*alist) {
tmp = gen_host(**alist++, 0xffffffff,
- tproto, dir);
+ tproto, dir, q.addr);
gen_or(b, tmp);
b = tmp;
}
sin = (struct sockaddr_in *)
res->ai_addr;
tmp = gen_host(ntohl(sin->sin_addr.s_addr),
- 0xffffffff, tproto, dir);
+ 0xffffffff, tproto, dir, q.addr);
break;
case AF_INET6:
if (tproto6 == Q_IP)
sin6 = (struct sockaddr_in6 *)
res->ai_addr;
tmp = gen_host6(&sin6->sin6_addr,
- &mask128, tproto6, dir);
+ &mask128, tproto6, dir, q.addr);
break;
default:
continue;
/* Convert mask len to mask */
if (masklen > 32)
bpf_error("mask length must be <= 32");
- m = 0xffffffff << (32 - masklen);
+ if (masklen == 0) {
+ /*
+ * X << 32 is not guaranteed by C to be 0; it's
+ * undefined.
+ */
+ m = 0;
+ } else
+ m = 0xffffffff << (32 - masklen);
if ((n & ~m) != 0)
bpf_error("non-network bits set in \"%s/%d\"",
s1, masklen);
switch (q.addr) {
case Q_NET:
- return gen_host(n, m, q.proto, q.dir);
+ return gen_host(n, m, q.proto, q.dir, q.addr);
default:
bpf_error("Mask syntax for networks only");
case Q_HOST:
case Q_NET:
if (proto == Q_DECNET)
- return gen_host(v, 0, proto, dir);
+ return gen_host(v, 0, proto, dir, q.addr);
else if (proto == Q_LINK) {
bpf_error("illegal link layer address");
} else {
v <<= 32 - vlen;
mask <<= 32 - vlen;
}
- return gen_host(v, mask, proto, dir);
+ return gen_host(v, mask, proto, dir, q.addr);
}
case Q_PORT:
/* FALLTHROUGH */
case Q_NET:
- b = gen_host6(addr, &mask, q.proto, q.dir);
+ b = gen_host6(addr, &mask, q.proto, q.dir, q.addr);
freeaddrinfo(res);
return b;
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);
- if (linktype == DLT_FDDI)
- return gen_fhostop(eaddr, (int)q.dir);
- if (linktype == DLT_IEEE802)
- return gen_thostop(eaddr, (int)q.dir);
- if (linktype == DLT_IEEE802_11)
- return gen_wlanhostop(eaddr, (int)q.dir);
- if (linktype == DLT_SUNATM && is_lane) {
+ switch (linktype) {
+ case DLT_EN10MB:
+ return gen_ehostop(eaddr, (int)q.dir);
+ case DLT_FDDI:
+ 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
gen_and(tmp, b);
return b;
}
- if (linktype == DLT_IP_OVER_FC)
- return gen_ipfchostop(eaddr, (int)q.dir);
+ 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");
+ break;
+ }
}
bpf_error("ethernet address used in non-ether expression");
/* NOTREACHED */
return s;
}
+/*
+ * Modify "index" to use the value stored into its register as an
+ * offset relative to the beginning of the header for the protocol
+ * "proto", and allocate a register and put an item "size" bytes long
+ * (1, 2, or 4) at that offset into that register, making it the register
+ * for "index".
+ */
struct arth *
gen_load(proto, index, size)
int proto;
default:
bpf_error("unsupported index operation");
+ case Q_RADIO:
+ /*
+ * The offset is relative to the beginning of the packet
+ * data, if we have a radio header. (If we don't, this
+ * is an error.)
+ */
+ if (linktype != DLT_IEEE802_11_RADIO_AVS &&
+ linktype != DLT_IEEE802_11_RADIO &&
+ linktype != DLT_PRISM_HEADER)
+ bpf_error("radio information not present in capture");
+
+ /*
+ * Load into the X register the offset computed into the
+ * register specifed by "index".
+ */
+ s = xfer_to_x(index);
+
+ /*
+ * Load the item at that offset.
+ */
+ tmp = new_stmt(BPF_LD|BPF_IND|size);
+ sappend(s, tmp);
+ sappend(index->s, s);
+ break;
+
case Q_LINK:
/*
+ * The offset is relative to the beginning of
+ * the link-layer header.
+ *
* 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
* frame, so that 0 refers, for Ethernet LANE, to
* the beginning of the destination address?
*/
- s = xfer_to_x(index);
+ s = gen_llprefixlen();
+
+ /*
+ * If "s" is non-null, it has code to arrange that the
+ * X register contains the length of the prefix preceding
+ * the link-layer header. Add to it the offset computed
+ * into the register specified by "index", and move that
+ * into the X register. Otherwise, just load into the X
+ * register the offset computed into the register specifed
+ * by "index".
+ */
+ if (s != NULL) {
+ sappend(s, xfer_to_a(index));
+ sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
+ sappend(s, new_stmt(BPF_MISC|BPF_TAX));
+ } else
+ s = xfer_to_x(index);
+
+ /*
+ * Load the item at the sum of the offset we've put in the
+ * X register and the offset of the start of the link
+ * layer header (which is 0 if the radio header is
+ * variable-length; that header length is what we put
+ * into the X register and then added to the index).
+ */
tmp = new_stmt(BPF_LD|BPF_IND|size);
+ tmp->s.k = off_ll;
sappend(s, tmp);
sappend(index->s, s);
break;
#ifdef INET6
case Q_IPV6:
#endif
- /* XXX Note that we assume a fixed link header here. */
- s = xfer_to_x(index);
+ /*
+ * The offset is relative to the beginning of
+ * the network-layer header.
+ * XXX - are there any cases where we want
+ * off_nl_nosnap?
+ */
+ s = gen_llprefixlen();
+
+ /*
+ * If "s" is non-null, it has code to arrange that the
+ * X register contains the length of the prefix preceding
+ * the link-layer header. Add to it the offset computed
+ * into the register specified by "index", and move that
+ * into the X register. Otherwise, just load into the X
+ * register the offset computed into the register specifed
+ * by "index".
+ */
+ if (s != NULL) {
+ sappend(s, xfer_to_a(index));
+ sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
+ sappend(s, new_stmt(BPF_MISC|BPF_TAX));
+ } else
+ s = xfer_to_x(index);
+
+ /*
+ * Load the item at the sum of the offset we've put in the
+ * X register and the offset of the start of the network
+ * layer header.
+ */
tmp = new_stmt(BPF_LD|BPF_IND|size);
tmp->s.k = off_nl;
sappend(s, tmp);
sappend(index->s, s);
+ /*
+ * Do the computation only if the packet contains
+ * the protocol in question.
+ */
b = gen_proto_abbrev(proto);
if (index->b)
gen_and(index->b, b);
case Q_IGRP:
case Q_PIM:
case Q_VRRP:
- s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
- s->s.k = off_nl;
+ /*
+ * The offset is relative to the beginning of
+ * the transport-layer header.
+ * XXX - are there any cases where we want
+ * off_nl_nosnap?
+ * XXX - we should, if we're built with
+ * IPv6 support, generate code to load either
+ * IPv4, IPv6, or both, as appropriate.
+ */
+ s = gen_loadx_iphdrlen();
+
+ /*
+ * The X register now contains the sum of the offset
+ * of the beginning of the link-layer header and
+ * the length of the network-layer header. Load
+ * into the A register the offset relative to
+ * the beginning of the transport layer header,
+ * add the X register to that, move that to the
+ * X register, and load with an offset from the
+ * X register equal to the offset of the network
+ * layer header relative to the beginning of
+ * the link-layer header.
+ */
sappend(s, xfer_to_a(index));
sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
sappend(s, new_stmt(BPF_MISC|BPF_TAX));
tmp->s.k = off_nl;
sappend(index->s, s);
+ /*
+ * Do the computation only if the packet contains
+ * the protocol in question - which is true only
+ * if this is an IP datagram and is the first or
+ * only fragment of that datagram.
+ */
gen_and(gen_proto_abbrev(proto), b = gen_ipfrag());
if (index->b)
gen_and(index->b, b);
return b;
}
+/*
+ * This is for "byte {idx} {op} {val}"; "idx" is treated as relative to
+ * the beginning of the link-layer header.
+ * XXX - that means you can't test values in the radiotap header, but
+ * as that header is difficult if not impossible to parse generally
+ * without a loop, that might not be a severe problem. A new keyword
+ * "radio" could be added for that, although what you'd really want
+ * would be a way of testing particular radio header values, which
+ * would generate code appropriate to the radio header in question.
+ */
struct block *
gen_byteop(op, idx, val)
int op, idx, val;
case Q_DEFAULT:
case Q_LINK:
- if (linktype == DLT_ARCNET || linktype == DLT_ARCNET_LINUX)
- return gen_ahostop(abroadcast, Q_DST);
- if (linktype == DLT_EN10MB)
- return gen_ehostop(ebroadcast, Q_DST);
- if (linktype == DLT_FDDI)
- return gen_fhostop(ebroadcast, Q_DST);
- if (linktype == DLT_IEEE802)
- return gen_thostop(ebroadcast, Q_DST);
- if (linktype == DLT_IEEE802_11)
- return gen_wlanhostop(ebroadcast, Q_DST);
- if (linktype == DLT_IP_OVER_FC)
- return gen_ipfchostop(ebroadcast, Q_DST);
- if (linktype == DLT_SUNATM && is_lane) {
+ switch (linktype) {
+ case DLT_ARCNET:
+ case DLT_ARCNET_LINUX:
+ return gen_ahostop(abroadcast, Q_DST);
+ case DLT_EN10MB:
+ return gen_ehostop(ebroadcast, Q_DST);
+ case DLT_FDDI:
+ return gen_fhostop(ebroadcast, Q_DST);
+ case DLT_IEEE802:
+ return gen_thostop(ebroadcast, Q_DST);
+ case DLT_IEEE802_11:
+ case DLT_IEEE802_11_RADIO_AVS:
+ case DLT_IEEE802_11_RADIO:
+ case DLT_PRISM_HEADER:
+ return gen_wlanhostop(ebroadcast, Q_DST);
+ case DLT_IP_OVER_FC:
+ return gen_ipfchostop(ebroadcast, Q_DST);
+ case DLT_SUNATM:
+ if (is_lane) {
/*
* Check that the packet doesn't begin with an
* LE Control marker. (We've already generated
b0 = gen_ehostop(ebroadcast, Q_DST);
gen_and(b1, b0);
return b0;
- }
- bpf_error("not a broadcast link");
+ }
+ break;
+ default:
+ bpf_error("not a broadcast link");
+ }
break;
case Q_IP:
case Q_DEFAULT:
case Q_LINK:
- if (linktype == DLT_ARCNET || linktype == DLT_ARCNET_LINUX)
- /* all ARCnet multicasts use the same address */
- return gen_ahostop(abroadcast, Q_DST);
-
- if (linktype == DLT_EN10MB) {
- /* ether[0] & 1 != 0 */
- return gen_mac_multicast(0);
- }
-
- if (linktype == DLT_FDDI) {
- /*
- * XXX TEST THIS: MIGHT NOT PORT PROPERLY XXX
- *
- * XXX - was that referring to bit-order issues?
- */
- /* fddi[1] & 1 != 0 */
- return gen_mac_multicast(1);
- }
-
- if (linktype == DLT_IEEE802) {
- /* tr[2] & 1 != 0 */
- return gen_mac_multicast(2);
- }
-
- if (linktype == DLT_IEEE802_11) {
- /*
- * Oh, yuk.
- *
- * For control frames, there is no DA.
- *
- * For management frames, DA is at an
- * offset of 4 from the beginning of
- * the packet.
- *
- * For data frames, DA is at an offset
- * of 4 from the beginning of the packet
- * if To DS is clear and at an offset of
- * 16 from the beginning of the packet
- * if To DS is set.
- */
-
- /*
- * Generate the tests to be done for data frames.
- *
- * First, check for To DS set, i.e. "link[1] & 0x01".
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x01; /* To DS */
- b1->stmts = s;
-
- /*
- * If To DS is set, the DA is at 16.
- */
- b0 = gen_mac_multicast(16);
- gen_and(b1, b0);
-
- /*
- * Now, check for To DS not set, i.e. check
- * "!(link[1] & 0x01)".
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b2 = new_block(JMP(BPF_JSET));
- b2->s.k = 0x01; /* To DS */
- b2->stmts = s;
- gen_not(b2);
-
- /*
- * If To DS is not set, the DA is at 4.
- */
- b1 = gen_mac_multicast(4);
- gen_and(b2, b1);
-
- /*
- * Now OR together the last two checks. That gives
- * the complete set of checks for data frames.
- */
- gen_or(b1, b0);
-
- /*
- * Now check for a data frame.
- * I.e, check "link[0] & 0x08".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x08;
- b1->stmts = s;
-
- /*
- * AND that with the checks done for data frames.
- */
- gen_and(b1, b0);
-
- /*
- * If the high-order bit of the type value is 0, this
- * is a management frame.
- * I.e, check "!(link[0] & 0x08)".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b2 = new_block(JMP(BPF_JSET));
- b2->s.k = 0x08;
- b2->stmts = s;
- gen_not(b2);
-
- /*
- * For management frames, the DA is at 4.
- */
- b1 = gen_mac_multicast(4);
- gen_and(b2, b1);
-
- /*
- * OR that with the checks done for data frames.
- * That gives the checks done for management and
- * data frames.
- */
- gen_or(b1, b0);
-
- /*
- * If the low-order bit of the type value is 1,
- * this is either a control frame or a frame
- * with a reserved type, and thus not a
- * frame with an SA.
- *
- * I.e., check "!(link[0] & 0x04)".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x04;
- b1->stmts = s;
- gen_not(b1);
-
- /*
- * AND that with the checks for data and management
- * frames.
- */
- gen_and(b1, b0);
- return b0;
- }
-
- if (linktype == DLT_IP_OVER_FC) {
- b0 = gen_mac_multicast(2);
- return b0;
- }
-
- if (linktype == DLT_SUNATM && is_lane) {
+ switch (linktype) {
+ case DLT_ARCNET:
+ case DLT_ARCNET_LINUX:
+ /* all ARCnet multicasts use the same address */
+ return gen_ahostop(abroadcast, Q_DST);
+ case DLT_EN10MB:
+ /* ether[0] & 1 != 0 */
+ return gen_mac_multicast(0);
+ case DLT_FDDI:
+ /*
+ * XXX TEST THIS: MIGHT NOT PORT PROPERLY XXX
+ *
+ * XXX - was that referring to bit-order issues?
+ */
+ /* fddi[1] & 1 != 0 */
+ return gen_mac_multicast(1);
+ case DLT_IEEE802:
+ /* tr[2] & 1 != 0 */
+ return gen_mac_multicast(2);
+ case DLT_IEEE802_11:
+ case DLT_IEEE802_11_RADIO_AVS:
+ case DLT_IEEE802_11_RADIO:
+ case DLT_PRISM_HEADER:
+ /*
+ * Oh, yuk.
+ *
+ * For control frames, there is no DA.
+ *
+ * For management frames, DA is at an
+ * offset of 4 from the beginning of
+ * the packet.
+ *
+ * For data frames, DA is at an offset
+ * of 4 from the beginning of the packet
+ * if To DS is clear and at an offset of
+ * 16 from the beginning of the packet
+ * if To DS is set.
+ */
+
+ /*
+ * Generate the tests to be done for data frames.
+ *
+ * First, check for To DS set, i.e. "link[1] & 0x01".
+ */
+ s = gen_load_a(OR_LINK, 1, BPF_B);
+ b1 = new_block(JMP(BPF_JSET));
+ b1->s.k = 0x01; /* To DS */
+ b1->stmts = s;
+
+ /*
+ * If To DS is set, the DA is at 16.
+ */
+ b0 = gen_mac_multicast(16);
+ gen_and(b1, b0);
+
+ /*
+ * Now, check for To DS not set, i.e. check
+ * "!(link[1] & 0x01)".
+ */
+ s = gen_load_a(OR_LINK, 1, BPF_B);
+ b2 = new_block(JMP(BPF_JSET));
+ b2->s.k = 0x01; /* To DS */
+ b2->stmts = s;
+ gen_not(b2);
+
+ /*
+ * If To DS is not set, the DA is at 4.
+ */
+ b1 = gen_mac_multicast(4);
+ gen_and(b2, b1);
+
+ /*
+ * Now OR together the last two checks. That gives
+ * the complete set of checks for data frames.
+ */
+ gen_or(b1, b0);
+
+ /*
+ * Now check for a data frame.
+ * I.e, check "link[0] & 0x08".
+ */
+ s = gen_load_a(OR_LINK, 0, BPF_B);
+ b1 = new_block(JMP(BPF_JSET));
+ b1->s.k = 0x08;
+ b1->stmts = s;
+
+ /*
+ * AND that with the checks done for data frames.
+ */
+ gen_and(b1, b0);
+
+ /*
+ * If the high-order bit of the type value is 0, this
+ * is a management frame.
+ * I.e, check "!(link[0] & 0x08)".
+ */
+ s = gen_load_a(OR_LINK, 0, BPF_B);
+ b2 = new_block(JMP(BPF_JSET));
+ b2->s.k = 0x08;
+ b2->stmts = s;
+ gen_not(b2);
+
+ /*
+ * For management frames, the DA is at 4.
+ */
+ b1 = gen_mac_multicast(4);
+ gen_and(b2, b1);
+
+ /*
+ * OR that with the checks done for data frames.
+ * That gives the checks done for management and
+ * data frames.
+ */
+ gen_or(b1, b0);
+
+ /*
+ * If the low-order bit of the type value is 1,
+ * this is either a control frame or a frame
+ * with a reserved type, and thus not a
+ * frame with an SA.
+ *
+ * I.e., check "!(link[0] & 0x04)".
+ */
+ s = gen_load_a(OR_LINK, 0, BPF_B);
+ b1 = new_block(JMP(BPF_JSET));
+ b1->s.k = 0x04;
+ b1->stmts = s;
+ gen_not(b1);
+
+ /*
+ * AND that with the checks for data and management
+ * frames.
+ */
+ gen_and(b1, b0);
+ return b0;
+ case DLT_IP_OVER_FC:
+ b0 = gen_mac_multicast(2);
+ return b0;
+ case DLT_SUNATM:
+ if (is_lane) {
/*
* Check that the packet doesn't begin with an
* LE Control marker. (We've already generated
b0 = gen_mac_multicast(off_mac);
gen_and(b1, b0);
return b0;
- }
-
- /* Link not known to support multicasts */
- break;
+ }
+ break;
+ default:
+ break;
+ }
+ /* Link not known to support multicasts */
+ break;
case Q_IP:
b0 = gen_linktype(ETHERTYPE_IP);
}
break;
+ case DLT_JUNIPER_MFR:
case DLT_JUNIPER_MLFR:
case DLT_JUNIPER_MLPPP:
case DLT_JUNIPER_ATM1:
case DLT_JUNIPER_ATM2:
+ case DLT_JUNIPER_PPPOE:
+ case DLT_JUNIPER_PPPOE_ATM:
+ case DLT_JUNIPER_GGSN:
+ case DLT_JUNIPER_ES:
+ case DLT_JUNIPER_MONITOR:
+ case DLT_JUNIPER_SERVICES:
+ case DLT_JUNIPER_ETHER:
+ case DLT_JUNIPER_PPP:
+ case DLT_JUNIPER_FRELAY:
+ case DLT_JUNIPER_CHDLC:
/* juniper flags (including direction) are stored
* the byte after the 3-byte magic number */
if (dir) {
return (b0);
}
-/* PF firewall log matched interface */
+/* PF firewall log ruleset name */
struct block *
gen_pf_ruleset(char *ruleset)
{
gen_vlan(vlan_num)
int vlan_num;
{
- struct block *b0;
+ struct block *b0, *b1;
+
+ /* can't check for VLAN-encapsulated packets inside MPLS */
+ if (label_stack_depth > 0)
+ bpf_error("no VLAN match after MPLS");
/*
* Change the offsets to point to the type and data fields within
* be done assuming a VLAN, even though the "or" could be viewed
* as meaning "or, if this isn't a VLAN packet...".
*/
- orig_linktype = off_linktype; /* save original values */
- orig_nl = off_nl;
+ orig_linktype = off_linktype; /* save original values */
+ orig_nl = off_nl;
- switch (linktype) {
+ switch (linktype) {
- case DLT_EN10MB:
- off_linktype += 4;
- off_nl_nosnap += 4;
- off_nl += 4;
- break;
+ case DLT_EN10MB:
+ off_linktype += 4;
+ off_nl_nosnap += 4;
+ off_nl += 4;
+ break;
- default:
- bpf_error("no VLAN support for data link type %d",
- linktype);
- /*NOTREACHED*/
- }
+ default:
+ bpf_error("no VLAN support for data link type %d",
+ linktype);
+ /*NOTREACHED*/
+ }
/* check for VLAN */
b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H, (bpf_int32)ETHERTYPE_8021Q);
/* If a specific VLAN is requested, check VLAN id */
if (vlan_num >= 0) {
- struct block *b1;
-
b1 = gen_mcmp(OR_LINK, orig_nl, BPF_H, (bpf_int32)vlan_num,
0x0fff);
gen_and(b0, b1);
gen_mpls(label_num)
int label_num;
{
- struct block *b0;
+ struct block *b0,*b1;
/*
* Change the offsets to point to the type and data fields within
*
* XXX - this is a bit of a kludge. See comments in gen_vlan().
*/
- orig_linktype = off_linktype; /* save original values */
orig_nl = off_nl;
- switch (linktype) {
-
- case DLT_C_HDLC: /* fall through */
- case DLT_EN10MB:
- off_linktype += 4;
- off_nl_nosnap += 4;
- off_nl += 4;
-
- b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H,
- (bpf_int32)ETHERTYPE_MPLS);
- break;
-
- case DLT_PPP:
- off_linktype += 4;
- off_nl_nosnap += 4;
- off_nl += 4;
-
- b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H,
- (bpf_int32)PPP_MPLS_UCAST);
- break;
-
- /* FIXME add other DLT_s ...
- * for Frame-Relay/and ATM this may get messy due to SNAP headers
- * leave it for now */
-
- default:
- bpf_error("no MPLS support for data link type %d",
+ if (label_stack_depth > 0) {
+ /* just match the bottom-of-stack bit clear */
+ b0 = gen_mcmp(OR_LINK, orig_nl-2, BPF_B, 0, 0x01);
+ } else {
+ /*
+ * Indicate that we're checking MPLS-encapsulated headers,
+ * to make sure higher level code generators don't try to
+ * match against IP-related protocols such as Q_ARP, Q_RARP
+ * etc.
+ */
+ switch (linktype) {
+
+ case DLT_C_HDLC: /* fall through */
+ case DLT_EN10MB:
+ b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
+ (bpf_int32)ETHERTYPE_MPLS);
+ break;
+
+ case DLT_PPP:
+ b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
+ (bpf_int32)PPP_MPLS_UCAST);
+ break;
+
+ /* FIXME add other DLT_s ...
+ * for Frame-Relay/and ATM this may get messy due to SNAP headers
+ * leave it for now */
+
+ default:
+ bpf_error("no MPLS support for data link type %d",
linktype);
- b0 = NULL;
- /*NOTREACHED*/
- break;
+ b0 = NULL;
+ /*NOTREACHED*/
+ break;
+ }
}
/* If a specific MPLS label is requested, check it */
if (label_num >= 0) {
- struct block *b1;
-
label_num = label_num << 12; /* label is shifted 12 bits on the wire */
b1 = gen_mcmp(OR_LINK, orig_nl, BPF_W, (bpf_int32)label_num,
0xfffff000); /* only compare the first 20 bits */
b0 = b1;
}
+ off_nl_nosnap += 4;
+ off_nl += 4;
+ label_stack_depth++;
return (b0);
}
+/*
+ * Support PPPOE discovery and session.
+ */
+struct block *
+gen_pppoed()
+{
+ /* check for PPPoE discovery */
+ return gen_linktype((bpf_int32)ETHERTYPE_PPPOED);
+}
+
+struct block *
+gen_pppoes()
+{
+ struct block *b0;
+
+ /*
+ * Test against the PPPoE session link-layer type.
+ */
+ b0 = gen_linktype((bpf_int32)ETHERTYPE_PPPOES);
+
+ /*
+ * Change the offsets to point to the type and data fields within
+ * the PPP packet.
+ *
+ * XXX - this is a bit of a kludge. If we were to split the
+ * compiler into a parser that parses an expression and
+ * generates an expression tree, and a code generator that
+ * takes an expression tree (which could come from our
+ * parser or from some other parser) and generates BPF code,
+ * we could perhaps make the offsets parameters of routines
+ * and, in the handler for an "AND" node, pass to subnodes
+ * other than the PPPoE node the adjusted offsets.
+ *
+ * This would mean that "pppoes" would, instead of changing the
+ * behavior of *all* tests after it, change only the behavior
+ * of tests ANDed with it. That would change the documented
+ * semantics of "pppoes", which might break some expressions.
+ * However, it would mean that "(pppoes and ip) or ip" would check
+ * both for VLAN-encapsulated IP and IP-over-Ethernet, rather than
+ * checking only for VLAN-encapsulated IP, so that could still
+ * be considered worth doing; it wouldn't break expressions
+ * that are of the form "pppoes and ..." which I suspect are the
+ * most common expressions involving "pppoes". "pppoes or ..."
+ * doesn't necessarily do what the user would really want, now,
+ * as all the "or ..." tests would be done assuming PPPoE, even
+ * though the "or" could be viewed as meaning "or, if this isn't
+ * a PPPoE packet...".
+ */
+ orig_linktype = off_linktype; /* save original values */
+ orig_nl = off_nl;
+
+ /*
+ * The "network-layer" protocol is PPPoE, which has a 6-byte
+ * PPPoE header, followed by PPP payload, so we set the
+ * offsets to the network layer offset plus 6 bytes for
+ * the PPPoE header plus the values appropriate for PPP when
+ * encapsulated in Ethernet (which means there's no HDLC
+ * encapsulation).
+ */
+ off_linktype = orig_nl + 6;
+ off_nl = orig_nl + 6 + 2;
+ off_nl_nosnap = orig_nl + 6 + 2;
+
+ /*
+ * Set the link-layer type to PPP, as all subsequent tests will
+ * be on the encapsulated PPP header.
+ */
+ linktype = DLT_PPP;
+
+ return b0;
+}
+
struct block *
gen_atmfield_code(atmfield, jvalue, jtype, reverse)
int atmfield;
return b1;
}
+struct block *
+gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
+ int mtp3field;
+ bpf_u_int32 jvalue;
+ bpf_u_int32 jtype;
+ int reverse;
+{
+ struct block *b0;
+ bpf_u_int32 val1 , val2 , val3;
+
+ switch (mtp3field) {
+
+ case M_SIO:
+ if (off_sio == (u_int)-1)
+ bpf_error("'sio' supported only on SS7");
+ /* sio coded on 1 byte so max value 255 */
+ if(jvalue > 255)
+ bpf_error("sio value %u too big; max value = 255",
+ jvalue);
+ b0 = gen_ncmp(OR_PACKET, off_sio, BPF_B, 0xffffffff,
+ (u_int)jtype, reverse, (u_int)jvalue);
+ break;
+
+ case M_OPC:
+ if (off_opc == (u_int)-1)
+ bpf_error("'opc' supported only on SS7");
+ /* opc coded on 14 bits so max value 16383 */
+ if (jvalue > 16383)
+ bpf_error("opc value %u too big; max value = 16383",
+ jvalue);
+ /* the following instructions are made to convert jvalue
+ * to the form used to write opc in an ss7 message*/
+ val1 = jvalue & 0x00003c00;
+ val1 = val1 >>10;
+ val2 = jvalue & 0x000003fc;
+ val2 = val2 <<6;
+ val3 = jvalue & 0x00000003;
+ val3 = val3 <<22;
+ jvalue = val1 + val2 + val3;
+ b0 = gen_ncmp(OR_PACKET, off_opc, BPF_W, 0x00c0ff0f,
+ (u_int)jtype, reverse, (u_int)jvalue);
+ break;
+
+ case M_DPC:
+ if (off_dpc == (u_int)-1)
+ bpf_error("'dpc' supported only on SS7");
+ /* dpc coded on 14 bits so max value 16383 */
+ if (jvalue > 16383)
+ bpf_error("dpc value %u too big; max value = 16383",
+ jvalue);
+ /* the following instructions are made to convert jvalue
+ * to the forme used to write dpc in an ss7 message*/
+ val1 = jvalue & 0x000000ff;
+ val1 = val1 << 24;
+ val2 = jvalue & 0x00003f00;
+ val2 = val2 << 8;
+ jvalue = val1 + val2;
+ b0 = gen_ncmp(OR_PACKET, off_dpc, BPF_W, 0xff3f0000,
+ (u_int)jtype, reverse, (u_int)jvalue);
+ break;
+
+ case M_SLS:
+ if (off_sls == (u_int)-1)
+ bpf_error("'sls' supported only on SS7");
+ /* sls coded on 4 bits so max value 15 */
+ if (jvalue > 15)
+ bpf_error("sls value %u too big; max value = 15",
+ jvalue);
+ /* the following instruction is made to convert jvalue
+ * to the forme used to write sls in an ss7 message*/
+ jvalue = jvalue << 4;
+ b0 = gen_ncmp(OR_PACKET, off_sls, BPF_B, 0xf0,
+ (u_int)jtype,reverse, (u_int)jvalue);
+ break;
+
+ default:
+ abort();
+ }
+ return b0;
+}
static struct block *
gen_msg_abbrev(type)
projects / libpcap / blobdiff