X-Git-Url: https://git.tcpdump.org/libpcap/blobdiff_plain/98a503e84307f830f1d42a33b701869f5e2ce4fb..2f23c057fc71caaea4e57a151d23c0d0fc6c2552:/gencode.c diff --git a/gencode.c b/gencode.c index af2218da..535f4a64 100644 --- a/gencode.c +++ b/gencode.c @@ -20,43 +20,75 @@ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ #ifndef lint -static const char rcsid[] = - "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.123 2000-10-22 04:15:55 guy Exp $ (LBL)"; +static const char rcsid[] _U_ = + "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.216 2005-01-12 09:02:55 hannes Exp $ (LBL)"; #endif #ifdef HAVE_CONFIG_H #include "config.h" #endif +#ifdef WIN32 +#include +#else /* WIN32 */ #include #include -#include +#endif /* WIN32 */ + +/* + * XXX - why was this included even on UNIX? + */ +#ifdef __MINGW32__ +#include "IP6_misc.h" +#endif + +#ifndef WIN32 + #ifdef __NetBSD__ #include #endif -struct mbuf; -struct rtentry; -#include - #include +#endif /* WIN32 */ + #include #include #include #include #include +#ifdef MSDOS +#include "pcap-dos.h" +#endif + #include "pcap-int.h" #include "ethertype.h" +#include "nlpid.h" +#include "llc.h" #include "gencode.h" +#include "atmuni31.h" +#include "sunatmpos.h" #include "ppp.h" -#include +#include "sll.h" +#include "arcnet.h" +#include "pf.h" +#ifndef offsetof +#define offsetof(s, e) ((size_t)&((s *)0)->e) +#endif #ifdef INET6 -#include -#include +#ifndef WIN32 +#include /* for "struct addrinfo" */ +#endif /* WIN32 */ #endif /*INET6*/ +#include + +#define ETHERMTU 1500 + +#ifndef IPPROTO_SCTP +#define IPPROTO_SCTP 132 +#endif #ifdef HAVE_OS_PROTO_H #include "os-proto.h" @@ -68,11 +100,12 @@ struct rtentry; 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, orig_nl_nosnap = -1U; + /* XXX */ #ifdef PCAP_FDDIPAD -int pcap_fddipad = PCAP_FDDIPAD; -#else -int pcap_fddipad; +static int pcap_fddipad; #endif /* VARARGS */ @@ -91,7 +124,7 @@ bpf_error(const char *fmt, ...) /* NOTREACHED */ } -static void init_linktype(int); +static void init_linktype(pcap_t *); static int alloc_reg(void); static void free_reg(int); @@ -101,8 +134,10 @@ static struct block *root; /* * We divy out chunks of memory rather than call malloc each time so * we don't have to worry about leaking memory. It's probably - * not a big deal if all this memory was wasted but it this ever + * not a big deal if all this memory was wasted but if this ever * goes into a library that would probably not be a good idea. + * + * XXX - this *is* in a library.... */ #define NCHUNKS 16 #define CHUNK0SIZE 1024 @@ -124,19 +159,29 @@ static inline void syntax(void); static void backpatch(struct block *, struct block *); static void merge(struct block *, struct block *); static struct block *gen_cmp(u_int, u_int, bpf_int32); +static struct block *gen_cmp_gt(u_int, u_int, bpf_int32); static struct block *gen_mcmp(u_int, u_int, bpf_int32, bpf_u_int32); static struct block *gen_bcmp(u_int, u_int, const u_char *); +static struct block *gen_ncmp(bpf_u_int32, bpf_u_int32, bpf_u_int32, + bpf_u_int32, bpf_u_int32, int); 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 struct block *gen_linktype(int); +static struct block *gen_snap(bpf_u_int32, bpf_u_int32, u_int); +static struct block *gen_llc(int); static struct block *gen_hostop(bpf_u_int32, bpf_u_int32, int, int, u_int, u_int); #ifdef INET6 static struct block *gen_hostop6(struct in6_addr *, struct in6_addr *, int, int, u_int, u_int); #endif +static struct block *gen_ahostop(const u_char *, int); static struct block *gen_ehostop(const u_char *, int); static struct block *gen_fhostop(const u_char *, int); static struct block *gen_thostop(const u_char *, 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, u_int); static struct block *gen_host(bpf_u_int32, bpf_u_int32, int, int); #ifdef INET6 @@ -161,14 +206,18 @@ static struct block *gen_protochain(int, int, int); static struct block *gen_proto(int, int, int); static struct slist *xfer_to_x(struct arth *); static struct slist *xfer_to_a(struct arth *); +static struct block *gen_mac_multicast(int); static struct block *gen_len(int, int); +static struct block *gen_msg_abbrev(int type); + static void * newchunk(n) u_int n; { struct chunk *cp; - int k, size; + int k; + size_t size; #ifndef __NetBSD__ /* XXX Round up to nearest long. */ @@ -185,6 +234,8 @@ newchunk(n) bpf_error("out of memory"); size = CHUNK0SIZE << k; cp->m = (void *)malloc(size); + if (cp->m == NULL) + bpf_error("out of memory"); memset((char *)cp->m, 0, size); cp->n_left = size; if (n > size) @@ -284,16 +335,8 @@ pcap_compile(pcap_t *p, struct bpf_program *program, } netmask = mask; - - /* On Linux we do not use the BPF filter to truncate the packet - * since the kernel provides other ways for that. In fact if we - * are using the packet filter for that duty we will be unable - * to acquire the original packet size. -- Torsten */ -#ifndef linux + snaplen = pcap_snapshot(p); -#else - snaplen = 0xffff; -#endif if (snaplen == 0) { snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snaplen of 0 rejects all packets"); @@ -301,7 +344,7 @@ pcap_compile(pcap_t *p, struct bpf_program *program, } lex_init(buf ? buf : ""); - init_linktype(pcap_datalink(p)); + init_linktype(p); (void)pcap_parse(); if (n_errors) @@ -319,6 +362,7 @@ pcap_compile(pcap_t *p, struct bpf_program *program, program->bf_insns = icode_to_fcode(root, &len); program->bf_len = len; + lex_cleanup(); freechunks(); return (0); } @@ -332,43 +376,29 @@ pcap_compile_nopcap(int snaplen_arg, int linktype_arg, struct bpf_program *program, char *buf, int optimize, bpf_u_int32 mask) { - extern int n_errors; - int len; + pcap_t *p; + int ret; - n_errors = 0; - root = NULL; - bpf_pcap = NULL; - if (setjmp(top_ctx)) { - freechunks(); + p = pcap_open_dead(linktype_arg, snaplen_arg); + if (p == NULL) return (-1); - } - - netmask = mask; - - /* XXX needed? I don't grok the use of globals here. */ - snaplen = snaplen_arg; - - lex_init(buf ? buf : ""); - init_linktype(linktype_arg); - (void)pcap_parse(); - - if (n_errors) - syntax(); - - if (root == NULL) - root = gen_retblk(snaplen_arg); + ret = pcap_compile(p, program, buf, optimize, mask); + pcap_close(p); + return (ret); +} - if (optimize) { - bpf_optimize(&root); - if (root == NULL || - (root->s.code == (BPF_RET|BPF_K) && root->s.k == 0)) - bpf_error("expression rejects all packets"); +/* + * Clean up a "struct bpf_program" by freeing all the memory allocated + * in it. + */ +void +pcap_freecode(struct bpf_program *program) +{ + program->bf_len = 0; + if (program->bf_insns != NULL) { + free((char *)program->bf_insns); + program->bf_insns = NULL; } - program->bf_insns = icode_to_fcode(root, &len); - program->bf_len = len; - - freechunks(); - return (0); } /* @@ -471,6 +501,24 @@ gen_cmp(offset, size, v) return b; } +static struct block * +gen_cmp_gt(offset, size, v) + u_int offset, size; + bpf_int32 v; +{ + struct slist *s; + struct block *b; + + s = new_stmt(BPF_LD|BPF_ABS|size); + s->s.k = offset; + + b = new_block(JMP(BPF_JGT)); + b->stmts = s; + b->s.k = v; + + return b; +} + static struct block * gen_mcmp(offset, size, v, mask) u_int offset, size; @@ -526,26 +574,155 @@ gen_bcmp(offset, size, v) return b; } +static struct block * +gen_ncmp(datasize, offset, mask, jtype, jvalue, reverse) + bpf_u_int32 datasize, offset, mask, jtype, jvalue; + int reverse; +{ + struct slist *s; + struct block *b; + + s = new_stmt(BPF_LD|datasize|BPF_ABS); + s->s.k = offset; + + if (mask != 0xffffffff) { + s->next = new_stmt(BPF_ALU|BPF_AND|BPF_K); + s->next->s.k = mask; + } + + b = new_block(JMP(jtype)); + b->stmts = s; + b->s.k = jvalue; + if (reverse && (jtype == BPF_JGT || jtype == BPF_JGE)) + gen_not(b); + return b; +} + /* * Various code constructs need to know the layout of the data link - * layer. These variables give the necessary offsets. off_linktype - * is set to -1 for no encapsulation, in which case, IP is assumed. + * 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. + * + * For Ethernet, it's the offset of the Ethernet type field. + * + * For link-layer types that always use 802.2 headers, it's the + * offset of the LLC header. + * + * For PPP, it's the offset of the PPP type field. + * + * For Cisco HDLC, it's the offset of the CHDLC type field. + * + * For BSD loopback, it's the offset of the AF_ value. + * + * For Linux cooked sockets, it's the offset of the type field. + * + * It's set to -1 for no encapsulation, in which case, IP is assumed. */ static u_int off_linktype; + +/* + * TRUE if the link layer includes an ATM pseudo-header. + */ +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_vpi; +static u_int off_vci; +static u_int off_proto; + +/* + * 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_payload; + +/* + * These are offsets to the beginning of the network-layer header. + * + * If the link layer never uses 802.2 LLC: + * + * "off_nl" and "off_nl_nosnap" are the same. + * + * If the link layer always uses 802.2 LLC: + * + * "off_nl" is the offset if there's a SNAP header following + * the 802.2 header; + * + * "off_nl_nosnap" is the offset if there's no SNAP header. + * + * If the link layer is Ethernet: + * + * "off_nl" is the offset if the packet is an Ethernet II packet + * (we assume no 802.3+802.2+SNAP); + * + * "off_nl_nosnap" is the offset if the packet is an 802.3 packet + * with an 802.2 header following it. + */ static u_int off_nl; +static u_int off_nl_nosnap; + static int linktype; static void -init_linktype(type) - int type; +init_linktype(p) + pcap_t *p; { - linktype = type; + linktype = pcap_datalink(p); +#ifdef PCAP_FDDIPAD + pcap_fddipad = p->fddipad; +#endif - switch (type) { + /* + * 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_payload = -1; + + orig_linktype = -1; + orig_nl = -1; + orig_nl_nosnap = -1; + + switch (linktype) { + + case DLT_ARCNET: + off_linktype = 2; + off_nl = 6; /* XXX in reality, variable! */ + off_nl_nosnap = 6; /* no 802.2 LLC */ + return; + + case DLT_ARCNET_LINUX: + off_linktype = 4; + off_nl = 8; /* XXX in reality, variable! */ + off_nl_nosnap = 8; /* no 802.2 LLC */ + return; case DLT_EN10MB: off_linktype = 12; - off_nl = 14; + off_nl = 14; /* Ethernet II */ + off_nl_nosnap = 17; /* 802.3+802.2 */ return; case DLT_SLIP: @@ -555,6 +732,7 @@ init_linktype(type) */ off_linktype = -1; off_nl = 16; + off_nl_nosnap = 16; /* no 802.2 LLC */ return; case DLT_SLIP_BSDOS: @@ -562,49 +740,75 @@ init_linktype(type) off_linktype = -1; /* XXX end */ off_nl = 24; + off_nl_nosnap = 24; /* no 802.2 LLC */ return; case DLT_NULL: + case DLT_LOOP: off_linktype = 0; off_nl = 4; + off_nl_nosnap = 4; /* no 802.2 LLC */ + return; + + case DLT_ENC: + off_linktype = 0; + off_nl = 12; + off_nl_nosnap = 12; /* no 802.2 LLC */ return; case DLT_PPP: - case DLT_C_HDLC: - case DLT_PPP_SERIAL: + case DLT_PPP_WITHDIRECTION: + case DLT_C_HDLC: /* BSD/OS Cisco HDLC */ + case DLT_PPP_SERIAL: /* NetBSD sync/async serial PPP */ off_linktype = 2; off_nl = 4; + off_nl_nosnap = 4; /* no 802.2 LLC */ + return; + + case DLT_PPP_ETHER: + /* + * This does no include the Ethernet header, and + * only covers session state. + */ + off_linktype = 6; + off_nl = 8; + off_nl_nosnap = 8; /* no 802.2 LLC */ return; case DLT_PPP_BSDOS: off_linktype = 5; off_nl = 24; + off_nl_nosnap = 24; /* no 802.2 LLC */ return; case DLT_FDDI: /* * FDDI doesn't really have a link-level type field. - * We assume that SSAP = SNAP is being used and pick - * out the encapsulated Ethernet type. + * We set "off_linktype" to the offset of the LLC header. * + * To check for Ethernet types, we assume that SSAP = SNAP + * is being used and pick out the encapsulated Ethernet type. * XXX - should we generate code to check for SNAP? */ - off_linktype = 19; + off_linktype = 13; #ifdef PCAP_FDDIPAD off_linktype += pcap_fddipad; #endif - off_nl = 21; + off_nl = 21; /* FDDI+802.2+SNAP */ + off_nl_nosnap = 16; /* FDDI+802.2 */ #ifdef PCAP_FDDIPAD off_nl += pcap_fddipad; + off_nl_nosnap += pcap_fddipad; #endif return; case DLT_IEEE802: /* * Token Ring doesn't really have a link-level type field. - * We assume that SSAP = SNAP is being used and pick - * out the encapsulated Ethernet type. + * We set "off_linktype" to the offset of the LLC header. * + * To check for Ethernet types, we assume that SSAP = SNAP + * is being used and pick out the encapsulated Ethernet type. * XXX - should we generate code to check for SNAP? * * XXX - the header is actually variable-length. @@ -622,30 +826,230 @@ init_linktype(type) * the 16-bit value at an offset of 14 (shifted right * 8 - figure out which byte that is). */ - off_linktype = 20; - off_nl = 22; + off_linktype = 14; + off_nl = 22; /* Token Ring+802.2+SNAP */ + off_nl_nosnap = 17; /* Token Ring+802.2 */ + return; + + case DLT_IEEE802_11: + /* + * 802.11 doesn't really have a link-level type field. + * We set "off_linktype" to the offset of the LLC header. + * + * To check for Ethernet types, we assume that SSAP = SNAP + * is being used and pick out the encapsulated Ethernet type. + * XXX - should we generate code to check for SNAP? + * + * XXX - the header is actually variable-length. We + * assume a 24-byte link-layer header, as appears in + * data frames in networks with no bridges. If the + * fromds and tods 802.11 header bits are both set, + * it's actually supposed to be 30 bytes. + */ + off_linktype = 24; + off_nl = 32; /* 802.11+802.2+SNAP */ + off_nl_nosnap = 27; /* 802.11+802.2 */ + return; + + case DLT_PRISM_HEADER: + /* + * Same as 802.11, but with an additional header before + * the 802.11 header, containing a bunch of additional + * information including radio-level information. + * + * The header is 144 bytes long. + * + * 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 */ + return; + + case DLT_IEEE802_11_RADIO_AVS: + /* + * Same as 802.11, but with an additional header before + * the 802.11 header, containing a bunch of additional + * information including radio-level information. + * + * The header is 64 bytes long, at least in its + * current incarnation. + * + * XXX - same variable-length header problem, only + * 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. + */ + off_linktype = 64+24; + off_nl = 64+32; /* Radio+802.11+802.2+SNAP */ + off_nl_nosnap = 64+27; /* Radio+802.11+802.2 */ + return; + + case DLT_IEEE802_11_RADIO: + /* + * Same as 802.11, but with an additional header before + * 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. + */ + off_linktype = -1; + off_nl = -1; + off_nl_nosnap = -1; return; case DLT_ATM_RFC1483: + case DLT_ATM_CLIP: /* Linux ATM defines this */ /* * assume routed, non-ISO PDUs * (i.e., LLC = 0xAA-AA-03, OUT = 0x00-00-00) */ - off_linktype = 6; - off_nl = 8; + off_linktype = 0; + off_nl = 8; /* 802.2+SNAP */ + off_nl_nosnap = 3; /* 802.2 */ + return; + + case DLT_SUNATM: + /* + * Full Frontal ATM; you get AALn PDUs with an ATM + * pseudo-header. + */ + is_atm = 1; + off_vpi = SUNATM_VPI_POS; + off_vci = SUNATM_VCI_POS; + off_proto = PROTO_POS; + 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: off_linktype = -1; off_nl = 0; + off_nl_nosnap = 0; /* no 802.2 LLC */ return; - case DLT_ATM_CLIP: /* Linux ATM defines this */ + case DLT_LINUX_SLL: /* fake header for Linux cooked socket */ + off_linktype = 14; + off_nl = 16; + off_nl_nosnap = 16; /* no 802.2 LLC */ + return; + + case DLT_LTALK: + /* + * LocalTalk does have a 1-byte type field in the LLAP header, + * but really it just indicates whether there is a "short" or + * "long" DDP packet following. + */ + off_linktype = -1; + off_nl = 0; + off_nl_nosnap = 0; /* no 802.2 LLC */ + return; + + case DLT_IP_OVER_FC: + /* + * RFC 2625 IP-over-Fibre-Channel doesn't really have a + * link-level type field. We set "off_linktype" to the + * offset of the LLC header. + * + * To check for Ethernet types, we assume that SSAP = SNAP + * is being used and pick out the encapsulated Ethernet type. + * XXX - should we generate code to check for SNAP? RFC + * 2625 says SNAP should be used. + */ + off_linktype = 16; + off_nl = 24; /* IPFC+802.2+SNAP */ + off_nl_nosnap = 19; /* IPFC+802.2 */ + return; + + case DLT_FRELAY: + /* + * XXX - we should set this to handle SNAP-encapsulated + * frames (NLPID of 0x80). + */ + off_linktype = -1; + off_nl = 0; + off_nl_nosnap = 0; /* no 802.2 LLC */ + return; + + case DLT_APPLE_IP_OVER_IEEE1394: + off_linktype = 16; + off_nl = 18; + off_nl_nosnap = 0; /* no 802.2 LLC */ + return; + + case DLT_LINUX_IRDA: + /* + * Currently, only raw "link[N:M]" filtering is supported. + */ + off_linktype = -1; + off_nl = -1; + off_nl_nosnap = -1; + return; + + case DLT_DOCSIS: + /* + * Currently, only raw "link[N:M]" filtering is supported. + */ + off_linktype = -1; + off_nl = -1; + off_nl_nosnap = -1; + return; + + case DLT_SYMANTEC_FIREWALL: off_linktype = 6; + off_nl = 44; /* Ethernet II */ + off_nl_nosnap = 44; /* XXX - what does it do with 802.3 packets? */ + return; + + case DLT_PFLOG: + off_linktype = 0; + /* XXX read from header? */ + off_nl = PFLOG_HDRLEN; + off_nl_nosnap = PFLOG_HDRLEN; + return; + + case DLT_JUNIPER_MLPPP: + off_linktype = 4; + off_nl = 4; + off_nl_nosnap = -1; + break; + + case DLT_JUNIPER_ATM1: + off_linktype = 4; /* in reality variable between 4-8 */ + off_nl = 4; + off_nl_nosnap = 14; + return; + + case DLT_JUNIPER_ATM2: + off_linktype = 8; /* in reality variable between 8-12 */ off_nl = 8; + off_nl_nosnap = 18; + return; + +#ifdef DLT_PFSYNC + case DLT_PFSYNC: + off_linktype = -1; + off_nl = 4; + off_nl_nosnap = 4; return; +#endif } - bpf_error("unknown data link type 0x%x", linktype); + bpf_error("unknown data link type %d", linktype); /* NOTREACHED */ } @@ -676,77 +1080,904 @@ gen_false() return gen_uncond(0); } +/* + * Byte-swap a 32-bit number. + * ("htonl()" or "ntohl()" won't work - we want to byte-swap even on + * big-endian platforms.) + */ +#define SWAPLONG(y) \ +((((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; - /* If we're not using encapsulation, we're done */ - if (off_linktype == -1) - return gen_true(); + switch (proto) { - switch (linktype) { + 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 DLT_SLIP: - return gen_false(); + case LLCSAP_IP: + b0 = gen_cmp_gt(off_linktype, BPF_H, ETHERMTU); + gen_not(b0); + b1 = gen_cmp(off_linktype + 2, BPF_H, (bpf_int32) + ((LLCSAP_IP << 8) | LLCSAP_IP)); + gen_and(b0, b1); + return b1; - case DLT_PPP: - case DLT_PPP_SERIAL: - if (proto == ETHERTYPE_IP) - proto = PPP_IP; /* XXX was 0x21 */ -#ifdef INET6 - else if (proto == ETHERTYPE_IPV6) - proto = PPP_IPV6; -#endif - break; + 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? + */ + + /* + * 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 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 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. + */ + + /* + * 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) { + /* + * 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); + } + } +} + +static struct block * +gen_linux_sll_linktype(proto) + register int proto; +{ + struct block *b0, *b1; + + switch (proto) { + + case LLCSAP_IP: + b0 = gen_cmp(off_linktype, BPF_H, LINUX_SLL_P_802_2); + b1 = gen_cmp(off_linktype + 2, BPF_H, (bpf_int32) + ((LLCSAP_IP << 8) | LLCSAP_IP)); + 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(off_linktype, BPF_H, LINUX_SLL_P_802_2); + 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 + * LSAP, like this, or should we check just the + * DSAP? + */ + b0 = gen_cmp(off_linktype, BPF_H, LINUX_SLL_P_802_2); + b1 = gen_cmp(off_linktype + 2, BPF_H, (bpf_int32) + ((LLCSAP_NETBEUI << 8) | LLCSAP_NETBEUI)); + gen_and(b0, b1); + return b1; + + case LLCSAP_IPX: + /* + * Ethernet_II frames, which are Ethernet + * frames with a frame type of ETHERTYPE_IPX; + * + * Ethernet_802.3 frames, which have a frame + * type of LINUX_SLL_P_802_3; + * + * Ethernet_802.2 frames, which are 802.3 + * frames with an 802.2 LLC header (i.e, have + * a frame type of LINUX_SLL_P_802_2) 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. + * + * First, do the checks on LINUX_SLL_P_802_2 + * frames; generate the check for either + * Ethernet_802.2 or Ethernet_SNAP frames, and + * then put a check for LINUX_SLL_P_802_2 frames + * before it. + */ + b0 = gen_cmp(off_linktype + 2, BPF_B, + (bpf_int32)LLCSAP_IPX); + b1 = gen_snap(0x000000, ETHERTYPE_IPX, + off_linktype + 2); + gen_or(b0, b1); + b0 = gen_cmp(off_linktype, BPF_H, LINUX_SLL_P_802_2); + gen_and(b0, b1); + + /* + * Now check for 802.3 frames and OR that with + * the previous test. + */ + b0 = gen_cmp(off_linktype, BPF_H, LINUX_SLL_P_802_3); + gen_or(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; + + 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 the 802.2 protocol type in the + * "Ethernet type" field. + */ + b0 = gen_cmp(off_linktype, BPF_H, LINUX_SLL_P_802_2); + + /* + * 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, + off_linktype + 2); + else /* proto == ETHERTYPE_AARP */ + b1 = gen_snap(0x000000, ETHERTYPE_AARP, + off_linktype + 2); + 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) { + /* + * This is an LLC SAP value, so the frames + * that match would be 802.2 frames. + * Check for the 802.2 protocol type + * in the "Ethernet type" field, and + * then check the DSAP. + */ + b0 = gen_cmp(off_linktype, BPF_H, + LINUX_SLL_P_802_2); + 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); + } + } +} + +static struct block * +gen_linktype(proto) + register int proto; +{ + struct block *b0, *b1, *b2; + + switch (linktype) { + + case DLT_EN10MB: + return gen_ether_linktype(proto); + /*NOTREACHED*/ + break; + + case DLT_C_HDLC: + switch (proto) { + + case LLCSAP_ISONS: + proto = (proto << 8 | LLCSAP_ISONS); + /* fall through */ + + default: + return gen_cmp(off_linktype, BPF_H, (bpf_int32)proto); + /*NOTREACHED*/ + break; + } + break; + + case DLT_IEEE802_11: + case DLT_PRISM_HEADER: + case DLT_IEEE802_11_RADIO: + case DLT_FDDI: + case DLT_IEEE802: + case DLT_ATM_RFC1483: + case DLT_ATM_CLIP: + case DLT_IP_OVER_FC: + return gen_llc(proto); + /*NOTREACHED*/ + break; + + case DLT_SUNATM: + /* + * 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. + */ + 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: + return gen_linux_sll_linktype(proto); + /*NOTREACHED*/ + break; + + case DLT_SLIP: + case DLT_SLIP_BSDOS: + case DLT_RAW: + /* + * These types don't provide any type field; packets + * are always IP. + * + * XXX - for IPv4, check for a version number of 4, and, + * for IPv6, check for a version number of 6? + */ + switch (proto) { + + case ETHERTYPE_IP: +#ifdef INET6 + case ETHERTYPE_IPV6: +#endif + return gen_true(); /* always true */ + + default: + return gen_false(); /* always false */ + } + /*NOTREACHED*/ + break; + + case DLT_PPP: + case DLT_PPP_WITHDIRECTION: + case DLT_PPP_SERIAL: + case DLT_PPP_ETHER: + /* + * We use Ethernet protocol types inside libpcap; + * map them to the corresponding PPP protocol types. + */ + switch (proto) { + + case ETHERTYPE_IP: + proto = PPP_IP; + break; + +#ifdef INET6 + case ETHERTYPE_IPV6: + proto = PPP_IPV6; + break; +#endif + + case ETHERTYPE_DN: + proto = PPP_DECNET; + break; + + case ETHERTYPE_ATALK: + proto = PPP_APPLE; + break; + + case ETHERTYPE_NS: + proto = PPP_NS; + break; + + case LLCSAP_ISONS: + proto = PPP_OSI; + break; + + case LLCSAP_8021D: + /* + * I'm assuming the "Bridging PDU"s that go + * over PPP are Spanning Tree Protocol + * Bridging PDUs. + */ + proto = PPP_BRPDU; + break; + + case LLCSAP_IPX: + proto = PPP_IPX; + break; + } + break; case DLT_PPP_BSDOS: + /* + * We use Ethernet protocol types inside libpcap; + * map them to the corresponding PPP protocol types. + */ + switch (proto) { + + case ETHERTYPE_IP: + b0 = gen_cmp(off_linktype, BPF_H, PPP_IP); + b1 = gen_cmp(off_linktype, BPF_H, PPP_VJC); + gen_or(b0, b1); + b0 = gen_cmp(off_linktype, BPF_H, PPP_VJNC); + gen_or(b1, b0); + return b0; + +#ifdef INET6 + case ETHERTYPE_IPV6: + proto = PPP_IPV6; + /* more to go? */ + break; +#endif + + case ETHERTYPE_DN: + proto = PPP_DECNET; + break; + + case ETHERTYPE_ATALK: + proto = PPP_APPLE; + break; + + case ETHERTYPE_NS: + proto = PPP_NS; + break; + + case LLCSAP_ISONS: + proto = PPP_OSI; + break; + + case LLCSAP_8021D: + /* + * I'm assuming the "Bridging PDU"s that go + * over PPP are Spanning Tree Protocol + * Bridging PDUs. + */ + proto = PPP_BRPDU; + break; + + case LLCSAP_IPX: + proto = PPP_IPX; + break; + } + break; + + case DLT_NULL: + case DLT_LOOP: + case DLT_ENC: + /* + * For DLT_NULL, the link-layer header is a 32-bit + * word containing an AF_ value in *host* byte order, + * and for DLT_ENC, the link-layer header begins + * with a 32-bit work containing an AF_ value in + * host byte order. + * + * In addition, if we're reading a saved capture file, + * the host byte order in the capture may not be the + * same as the host byte order on this machine. + * + * For DLT_LOOP, the link-layer header is a 32-bit + * word containing an AF_ value in *network* byte order. + * + * XXX - AF_ values may, unfortunately, be platform- + * dependent; for example, FreeBSD's AF_INET6 is 24 + * whilst NetBSD's and OpenBSD's is 26. + * + * This means that, when reading a capture file, just + * checking for our AF_INET6 value won't work if the + * capture file came from another OS. + */ + switch (proto) { + + case ETHERTYPE_IP: + proto = AF_INET; + break; + +#ifdef INET6 + case ETHERTYPE_IPV6: + proto = AF_INET6; + break; +#endif + + default: + /* + * Not a type on which we support filtering. + * XXX - support those that have AF_ values + * #defined on this platform, at least? + */ + return gen_false(); + } + + if (linktype == DLT_NULL || linktype == DLT_ENC) { + /* + * The AF_ value is in host byte order, but + * the BPF interpreter will convert it to + * network byte order. + * + * If this is a save file, and it's from a + * machine with the opposite byte order to + * ours, we byte-swap the AF_ value. + * + * Then we run it through "htonl()", and + * generate code to compare against the result. + */ + if (bpf_pcap->sf.rfile != NULL && + bpf_pcap->sf.swapped) + proto = SWAPLONG(proto); + proto = htonl(proto); + } + return (gen_cmp(0, BPF_W, (bpf_int32)proto)); + + case DLT_PFLOG: + /* + * af field is host byte order in contrast to the rest of + * the packet. + */ + if (proto == ETHERTYPE_IP) + return (gen_cmp(offsetof(struct pfloghdr, af), BPF_B, + (bpf_int32)AF_INET)); +#ifdef INET6 + else if (proto == ETHERTYPE_IPV6) + return (gen_cmp(offsetof(struct pfloghdr, af), BPF_B, + (bpf_int32)AF_INET6)); +#endif /* INET6 */ + else + return gen_false(); + /*NOTREACHED*/ + break; + + case DLT_ARCNET: + case DLT_ARCNET_LINUX: + /* + * XXX should we check for first fragment if the protocol + * uses PHDS? + */ + switch (proto) { + + default: + return gen_false(); + +#ifdef INET6 + case ETHERTYPE_IPV6: + return (gen_cmp(off_linktype, BPF_B, + (bpf_int32)ARCTYPE_INET6)); +#endif /* INET6 */ + + case ETHERTYPE_IP: + b0 = gen_cmp(off_linktype, BPF_B, + (bpf_int32)ARCTYPE_IP); + b1 = gen_cmp(off_linktype, BPF_B, + (bpf_int32)ARCTYPE_IP_OLD); + gen_or(b0, b1); + return (b1); + + case ETHERTYPE_ARP: + b0 = gen_cmp(off_linktype, BPF_B, + (bpf_int32)ARCTYPE_ARP); + b1 = gen_cmp(off_linktype, BPF_B, + (bpf_int32)ARCTYPE_ARP_OLD); + gen_or(b0, b1); + return (b1); + + case ETHERTYPE_REVARP: + return (gen_cmp(off_linktype, BPF_B, + (bpf_int32)ARCTYPE_REVARP)); + + case ETHERTYPE_ATALK: + return (gen_cmp(off_linktype, BPF_B, + (bpf_int32)ARCTYPE_ATALK)); + } + /*NOTREACHED*/ + break; + + case DLT_LTALK: + switch (proto) { + case ETHERTYPE_ATALK: + return gen_true(); + default: + return gen_false(); + } + /*NOTREACHED*/ + break; + + case DLT_FRELAY: + /* + * XXX - assumes a 2-byte Frame Relay header with + * DLCI and flags. What if the address is longer? + */ switch (proto) { case ETHERTYPE_IP: - b0 = gen_cmp(off_linktype, BPF_H, PPP_IP); - b1 = gen_cmp(off_linktype, BPF_H, PPP_VJC); - gen_or(b0, b1); - b0 = gen_cmp(off_linktype, BPF_H, PPP_VJNC); - gen_or(b1, b0); - return b0; + /* + * Check for the special NLPID for IP. + */ + return gen_cmp(2, BPF_H, (0x03<<8) | 0xcc); #ifdef INET6 case ETHERTYPE_IPV6: - proto = PPP_IPV6; - /* more to go? */ - break; + /* + * Check for the special NLPID for IPv6. + */ + return gen_cmp(2, BPF_H, (0x03<<8) | 0x8e); #endif - case ETHERTYPE_DN: - proto = PPP_DECNET; - break; - - case ETHERTYPE_ATALK: - proto = PPP_APPLE; - break; + case LLCSAP_ISONS: + /* + * Check for several OSI protocols. + * + * Frame Relay packets typically have an OSI + * NLPID at the beginning; we check for each + * of them. + * + * What we check for is the NLPID and a frame + * control field of UI, i.e. 0x03 followed + * by the NLPID. + */ + b0 = gen_cmp(2, BPF_H, (0x03<<8) | ISO8473_CLNP); + b1 = gen_cmp(2, BPF_H, (0x03<<8) | ISO9542_ESIS); + b2 = gen_cmp(2, BPF_H, (0x03<<8) | ISO10589_ISIS); + gen_or(b1, b2); + gen_or(b0, b2); + return b2; - case ETHERTYPE_NS: - proto = PPP_NS; - break; + default: + return gen_false(); } + /*NOTREACHED*/ break; - case DLT_NULL: - /* XXX */ - if (proto == ETHERTYPE_IP) - return (gen_cmp(0, BPF_W, (bpf_int32)htonl(AF_INET))); -#ifdef INET6 - else if (proto == ETHERTYPE_IPV6) - return (gen_cmp(0, BPF_W, (bpf_int32)htonl(AF_INET6))); -#endif - else - return gen_false(); + case DLT_JUNIPER_MLPPP: + case DLT_JUNIPER_ATM1: + case DLT_JUNIPER_ATM2: + /* just lets verify the magic number for now - + * we may have up to 6 different encapsulations on the wire + * and need a lot of heuristics to figure out that the payload + * might be; + * + * FIXME encapsulation specific BPF_ filters + */ + return gen_mcmp(0, BPF_W, 0x4d474300, 0xffffff00); /* compare the magic number */ + + case DLT_LINUX_IRDA: + bpf_error("IrDA link-layer type filtering not implemented"); + + case DLT_DOCSIS: + bpf_error("DOCSIS link-layer type filtering not implemented"); } + + /* + * All the types that have no encapsulation should either be + * handled as DLT_SLIP, DLT_SLIP_BSDOS, and DLT_RAW are, if + * all packets are IP packets, or should be handled in some + * special case, if none of them are (if some are and some + * aren't, the lack of encapsulation is a problem, as we'd + * have to find some other way of determining the packet type). + * + * Therefore, if "off_linktype" is -1, there's an error. + */ + if (off_linktype == (u_int)-1) + abort(); + + /* + * Any type not handled above should always have an Ethernet + * type at an offset of "off_linktype". (PPP is partially + * handled above - the protocol type is mapped from the + * Ethernet and LLC types we use internally to the corresponding + * PPP type - but the PPP type is always specified by a value + * at "off_linktype", so we don't have to do the code generation + * above.) + */ return gen_cmp(off_linktype, BPF_H, (bpf_int32)proto); } +/* + * Check for an LLC SNAP packet with a given organization code and + * protocol type; we check the entire contents of the 802.2 LLC and + * snap headers, checking for DSAP and SSAP of SNAP and a control + * field of 0x03 in the LLC header, and for the specified organization + * code and protocol type in the SNAP header. + */ +static struct block * +gen_snap(orgcode, ptype, offset) + bpf_u_int32 orgcode; + bpf_u_int32 ptype; + u_int offset; +{ + u_char snapblock[8]; + + snapblock[0] = LLCSAP_SNAP; /* DSAP = SNAP */ + snapblock[1] = LLCSAP_SNAP; /* SSAP = SNAP */ + 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 */ + snapblock[6] = (ptype >> 8); /* upper 8 bits of protocol type */ + snapblock[7] = (ptype >> 0); /* lower 8 bits of protocol type */ + return gen_bcmp(offset, 8, snapblock); +} + +/* + * Check for a given protocol value assuming an 802.2 LLC header. + */ +static struct block * +gen_llc(proto) + int proto; +{ + /* + * XXX - handle token-ring variable-length header. + */ + switch (proto) { + + case LLCSAP_IP: + return gen_cmp(off_linktype, BPF_H, (long) + ((LLCSAP_IP << 8) | LLCSAP_IP)); + + case LLCSAP_ISONS: + return gen_cmp(off_linktype, BPF_H, (long) + ((LLCSAP_ISONS << 8) | LLCSAP_ISONS)); + + case LLCSAP_NETBEUI: + return gen_cmp(off_linktype, BPF_H, (long) + ((LLCSAP_NETBEUI << 8) | LLCSAP_NETBEUI)); + + case LLCSAP_IPX: + /* + * XXX - are there ever SNAP frames for IPX on + * non-Ethernet 802.x networks? + */ + return gen_cmp(off_linktype, BPF_B, (bpf_int32)LLCSAP_IPX); + + case ETHERTYPE_ATALK: + /* + * 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). + * + * XXX - check for an organization code of + * encapsulated Ethernet as well? + */ + return gen_snap(0x080007, ETHERTYPE_ATALK, off_linktype); + + default: + /* + * XXX - we don't have to check for IPX 802.3 + * here, but should we check for the IPX Ethertype? + */ + if (proto <= ETHERMTU) { + /* + * This is an LLC SAP value, so check + * the DSAP. + */ + return gen_cmp(off_linktype, BPF_B, (bpf_int32)proto); + } else { + /* + * This is an Ethernet type; we assume that it's + * unlikely that it'll appear in the right place + * at random, and therefore check only the + * location that would hold the Ethernet type + * in a SNAP frame with an organization code of + * 0x000000 (encapsulated Ethernet). + * + * XXX - if we were to check for the SNAP DSAP and + * LSAP, as per XXX, and were also to check for an + * organization code of 0x000000 (encapsulated + * Ethernet), we'd do + * + * return gen_snap(0x000000, proto, + * off_linktype); + * + * here; for now, we don't, as per the above. + * I don't know whether it's worth the extra CPU + * time to do the right check or not. + */ + return gen_cmp(off_linktype+6, BPF_H, (bpf_int32)proto); + } + } +} + static struct block * gen_hostop(addr, mask, dir, proto, src_off, dst_off) bpf_u_int32 addr; @@ -850,65 +2081,405 @@ gen_ehostop(eaddr, dir) { register struct block *b0, *b1; - switch (dir) { - case Q_SRC: - return gen_bcmp(6, 6, eaddr); + switch (dir) { + case Q_SRC: + return gen_bcmp(off_mac + 6, 6, eaddr); + + case Q_DST: + return gen_bcmp(off_mac + 0, 6, eaddr); + + case Q_AND: + b0 = gen_ehostop(eaddr, Q_SRC); + b1 = gen_ehostop(eaddr, Q_DST); + gen_and(b0, b1); + return b1; + + case Q_DEFAULT: + case Q_OR: + b0 = gen_ehostop(eaddr, Q_SRC); + b1 = gen_ehostop(eaddr, Q_DST); + gen_or(b0, b1); + return b1; + } + abort(); + /* NOTREACHED */ +} + +/* + * Like gen_ehostop, but for DLT_FDDI + */ +static struct block * +gen_fhostop(eaddr, dir) + register const u_char *eaddr; + register int dir; +{ + struct block *b0, *b1; + + switch (dir) { + case Q_SRC: +#ifdef PCAP_FDDIPAD + return gen_bcmp(6 + 1 + pcap_fddipad, 6, eaddr); +#else + return gen_bcmp(6 + 1, 6, eaddr); +#endif + + case Q_DST: +#ifdef PCAP_FDDIPAD + return gen_bcmp(0 + 1 + pcap_fddipad, 6, eaddr); +#else + return gen_bcmp(0 + 1, 6, eaddr); +#endif + + case Q_AND: + b0 = gen_fhostop(eaddr, Q_SRC); + b1 = gen_fhostop(eaddr, Q_DST); + gen_and(b0, b1); + return b1; + + case Q_DEFAULT: + case Q_OR: + b0 = gen_fhostop(eaddr, Q_SRC); + b1 = gen_fhostop(eaddr, Q_DST); + gen_or(b0, b1); + return b1; + } + abort(); + /* NOTREACHED */ +} + +/* + * Like gen_ehostop, but for DLT_IEEE802 (Token Ring) + */ +static struct block * +gen_thostop(eaddr, dir) + register const u_char *eaddr; + register int dir; +{ + register struct block *b0, *b1; + + switch (dir) { + case Q_SRC: + return gen_bcmp(8, 6, eaddr); + + case Q_DST: + return gen_bcmp(2, 6, eaddr); + + case Q_AND: + b0 = gen_thostop(eaddr, Q_SRC); + b1 = gen_thostop(eaddr, Q_DST); + gen_and(b0, b1); + return b1; + + case Q_DEFAULT: + case Q_OR: + b0 = gen_thostop(eaddr, Q_SRC); + b1 = gen_thostop(eaddr, Q_DST); + gen_or(b0, b1); + return b1; + } + abort(); + /* NOTREACHED */ +} + +/* + * Like gen_ehostop, but for DLT_IEEE802_11 (802.11 wireless LAN) + */ +static struct block * +gen_wlanhostop(eaddr, dir) + register const u_char *eaddr; + register int dir; +{ + register struct block *b0, *b1, *b2; + register struct slist *s; + + switch (dir) { + case Q_SRC: + /* + * Oh, yuk. + * + * For control frames, there is no SA. + * + * For management frames, SA is at an + * offset of 10 from the beginning of + * the packet. + * + * For data frames, SA is at an offset + * of 10 from the beginning of the packet + * if From DS is clear, at an offset of + * 16 from the beginning of the packet + * if From DS is set and To DS is clear, + * and an offset of 24 from the beginning + * of the packet if From DS is set and To DS + * is set. + */ + + /* + * Generate the tests to be done for data frames + * with From DS set. + * + * First, check for To DS set, i.e. check "link[1] & 0x01". + */ + s = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 1; + b1 = new_block(JMP(BPF_JSET)); + b1->s.k = 0x01; /* To DS */ + b1->stmts = s; + + /* + * If To DS is set, the SA is at 24. + */ + b0 = gen_bcmp(24, 6, eaddr); + gen_and(b1, b0); + + /* + * Now, check for To DS not set, i.e. check + * "!(link[1] & 0x01)". + */ + s = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 1; + 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 SA is at 16. + */ + b1 = gen_bcmp(16, 6, eaddr); + gen_and(b2, b1); + + /* + * Now OR together the last two checks. That gives + * the complete set of checks for data frames with + * From DS set. + */ + gen_or(b1, b0); + + /* + * Now check for From DS being set, and AND that with + * the ORed-together checks. + */ + s = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 1; + b1 = new_block(JMP(BPF_JSET)); + b1->s.k = 0x02; /* From DS */ + b1->stmts = s; + gen_and(b1, b0); + + /* + * Now check for data frames with From DS not set. + */ + s = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 1; + b2 = new_block(JMP(BPF_JSET)); + b2->s.k = 0x02; /* From DS */ + b2->stmts = s; + gen_not(b2); + + /* + * If From DS isn't set, the SA is at 10. + */ + b1 = gen_bcmp(10, 6, eaddr); + gen_and(b2, b1); + + /* + * Now OR together the checks for data frames with + * From DS not set and for data frames with From DS + * set; that gives the checks done for data frames. + */ + gen_or(b1, b0); + + /* + * Now check for a data frame. + * I.e, check "link[0] & 0x08". + */ + s = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 0; + 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 0; + b2 = new_block(JMP(BPF_JSET)); + b2->s.k = 0x08; + b2->stmts = s; + gen_not(b2); + + /* + * For management frames, the SA is at 10. + */ + b1 = gen_bcmp(10, 6, eaddr); + 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 0; + 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 Q_DST: - return gen_bcmp(0, 6, eaddr); + /* + * 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. + */ - case Q_AND: - b0 = gen_ehostop(eaddr, Q_SRC); - b1 = gen_ehostop(eaddr, Q_DST); - gen_and(b0, b1); - return b1; + /* + * Generate the tests to be done for data frames. + * + * First, check for To DS set, i.e. "link[1] & 0x01". + */ + s = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 1; + b1 = new_block(JMP(BPF_JSET)); + b1->s.k = 0x01; /* To DS */ + b1->stmts = s; - case Q_DEFAULT: - case Q_OR: - b0 = gen_ehostop(eaddr, Q_SRC); - b1 = gen_ehostop(eaddr, Q_DST); - gen_or(b0, b1); - return b1; - } - abort(); - /* NOTREACHED */ -} + /* + * If To DS is set, the DA is at 16. + */ + b0 = gen_bcmp(16, 6, eaddr); + gen_and(b1, b0); -/* - * Like gen_ehostop, but for DLT_FDDI - */ -static struct block * -gen_fhostop(eaddr, dir) - register const u_char *eaddr; - register int dir; -{ - struct block *b0, *b1; + /* + * Now, check for To DS not set, i.e. check + * "!(link[1] & 0x01)". + */ + s = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 1; + b2 = new_block(JMP(BPF_JSET)); + b2->s.k = 0x01; /* To DS */ + b2->stmts = s; + gen_not(b2); - switch (dir) { - case Q_SRC: -#ifdef PCAP_FDDIPAD - return gen_bcmp(6 + 1 + pcap_fddipad, 6, eaddr); -#else - return gen_bcmp(6 + 1, 6, eaddr); -#endif + /* + * If To DS is not set, the DA is at 4. + */ + b1 = gen_bcmp(4, 6, eaddr); + gen_and(b2, b1); - case Q_DST: -#ifdef PCAP_FDDIPAD - return gen_bcmp(0 + 1 + pcap_fddipad, 6, eaddr); -#else - return gen_bcmp(0 + 1, 6, eaddr); -#endif + /* + * 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 0; + 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 0; + 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_bcmp(4, 6, eaddr); + 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 0; + 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 Q_AND: - b0 = gen_fhostop(eaddr, Q_SRC); - b1 = gen_fhostop(eaddr, Q_DST); + b0 = gen_wlanhostop(eaddr, Q_SRC); + b1 = gen_wlanhostop(eaddr, Q_DST); gen_and(b0, b1); return b1; case Q_DEFAULT: case Q_OR: - b0 = gen_fhostop(eaddr, Q_SRC); - b1 = gen_fhostop(eaddr, Q_DST); + b0 = gen_wlanhostop(eaddr, Q_SRC); + b1 = gen_wlanhostop(eaddr, Q_DST); gen_or(b0, b1); return b1; } @@ -917,10 +2488,12 @@ gen_fhostop(eaddr, dir) } /* - * Like gen_ehostop, but for DLT_IEEE802 (Token Ring) + * Like gen_ehostop, but for RFC 2625 IP-over-Fibre-Channel. + * (We assume that the addresses are IEEE 48-bit MAC addresses, + * as the RFC states.) */ static struct block * -gen_thostop(eaddr, dir) +gen_ipfchostop(eaddr, dir) register const u_char *eaddr; register int dir; { @@ -928,21 +2501,21 @@ gen_thostop(eaddr, dir) switch (dir) { case Q_SRC: - return gen_bcmp(8, 6, eaddr); + return gen_bcmp(10, 6, eaddr); case Q_DST: return gen_bcmp(2, 6, eaddr); case Q_AND: - b0 = gen_thostop(eaddr, Q_SRC); - b1 = gen_thostop(eaddr, Q_DST); + b0 = gen_ipfchostop(eaddr, Q_SRC); + b1 = gen_ipfchostop(eaddr, Q_DST); gen_and(b0, b1); return b1; case Q_DEFAULT: case Q_OR: - b0 = gen_thostop(eaddr, Q_SRC); - b1 = gen_thostop(eaddr, Q_DST); + b0 = gen_ipfchostop(eaddr, Q_SRC); + b1 = gen_ipfchostop(eaddr, Q_DST); gen_or(b0, b1); return b1; } @@ -1005,6 +2578,9 @@ gen_dnhostop(addr, dir, base_off) gen_or(b0, b1); return b1; + case Q_ISO: + bpf_error("ISO host filtering not implemented"); + default: abort(); } @@ -1051,7 +2627,7 @@ gen_host(addr, mask, proto, dir) case Q_DEFAULT: b0 = gen_host(addr, mask, Q_IP, dir); - if (off_linktype != -1) { + 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); @@ -1074,6 +2650,9 @@ gen_host(addr, mask, proto, dir) case Q_TCP: bpf_error("'tcp' modifier applied to host"); + case Q_SCTP: + bpf_error("'sctp' modifier applied to host"); + case Q_UDP: bpf_error("'udp' modifier applied to host"); @@ -1089,9 +2668,15 @@ gen_host(addr, mask, proto, dir) case Q_PIM: bpf_error("'pim' modifier applied to host"); + case Q_VRRP: + bpf_error("'vrrp' modifier applied to host"); + case Q_ATALK: bpf_error("ATALK host filtering not implemented"); + case Q_AARP: + bpf_error("AARP host filtering not implemented"); + case Q_DECNET: return gen_dnhostop(addr, dir, off_nl); @@ -1121,6 +2706,27 @@ gen_host(addr, mask, proto, dir) case Q_ESP: bpf_error("'esp' modifier applied to host"); + case Q_ISO: + bpf_error("ISO host filtering not implemented"); + + case Q_ESIS: + bpf_error("'esis' modifier applied to host"); + + case Q_ISIS: + bpf_error("'isis' modifier applied to host"); + + case Q_CLNP: + bpf_error("'clnp' modifier applied to host"); + + case Q_STP: + bpf_error("'stp' modifier applied to host"); + + case Q_IPX: + bpf_error("IPX host filtering not implemented"); + + case Q_NETBEUI: + bpf_error("'netbeui' modifier applied to host"); + default: abort(); } @@ -1149,6 +2755,9 @@ gen_host6(addr, mask, proto, dir) case Q_ARP: bpf_error("'arp' modifier applied to ip6 host"); + case Q_SCTP: + bpf_error("'sctp' modifier applied to host"); + case Q_TCP: bpf_error("'tcp' modifier applied to host"); @@ -1167,9 +2776,15 @@ gen_host6(addr, mask, proto, dir) case Q_PIM: bpf_error("'pim' modifier applied to host"); + case Q_VRRP: + bpf_error("'vrrp' modifier applied to host"); + case Q_ATALK: bpf_error("ATALK host filtering not implemented"); + case Q_AARP: + bpf_error("AARP host filtering not implemented"); + case Q_DECNET: bpf_error("'decnet' modifier applied to ip6 host"); @@ -1198,6 +2813,27 @@ gen_host6(addr, mask, proto, dir) case Q_ESP: bpf_error("'esp' modifier applied to host"); + case Q_ISO: + bpf_error("ISO host filtering not implemented"); + + case Q_ESIS: + bpf_error("'esis' modifier applied to host"); + + case Q_ISIS: + bpf_error("'isis' modifier applied to host"); + + case Q_CLNP: + bpf_error("'clnp' modifier applied to host"); + + case Q_STP: + bpf_error("'stp' modifier applied to host"); + + case Q_IPX: + bpf_error("IPX host filtering not implemented"); + + case Q_NETBEUI: + bpf_error("'netbeui' modifier applied to host"); + default: abort(); } @@ -1229,9 +2865,27 @@ gen_gateway(eaddr, alist, proto, dir) 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) { + /* + * 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 if (linktype == DLT_IP_OVER_FC) + b0 = gen_ipfchostop(eaddr, Q_OR); else bpf_error( - "'gateway' supported only on ethernet, FDDI or token ring"); + "'gateway' supported only on ethernet/FDDI/token ring/802.11/Fibre Channel"); b1 = gen_host(**alist++, 0xffffffff, proto, Q_OR); while (*alist) { @@ -1252,13 +2906,19 @@ struct block * gen_proto_abbrev(proto) int proto; { -#ifdef INET6 struct block *b0; -#endif struct block *b1; switch (proto) { + case Q_SCTP: + b1 = gen_proto(IPPROTO_SCTP, Q_IP, Q_DEFAULT); +#ifdef INET6 + b0 = gen_proto(IPPROTO_SCTP, Q_IPV6, Q_DEFAULT); + gen_or(b0, b1); +#endif + break; + case Q_TCP: b1 = gen_proto(IPPROTO_TCP, Q_IP, Q_DEFAULT); #ifdef INET6 @@ -1306,6 +2966,14 @@ gen_proto_abbrev(proto) #endif break; +#ifndef IPPROTO_VRRP +#define IPPROTO_VRRP 112 +#endif + + case Q_VRRP: + b1 = gen_proto(IPPROTO_VRRP, Q_IP, Q_DEFAULT); + break; + case Q_IP: b1 = gen_linktype(ETHERTYPE_IP); break; @@ -1325,6 +2993,10 @@ gen_proto_abbrev(proto) b1 = gen_linktype(ETHERTYPE_ATALK); break; + case Q_AARP: + b1 = gen_linktype(ETHERTYPE_AARP); + break; + case Q_DECNET: b1 = gen_linktype(ETHERTYPE_DN); break; @@ -1380,6 +3052,94 @@ gen_proto_abbrev(proto) #endif break; + case Q_ISO: + b1 = gen_linktype(LLCSAP_ISONS); + break; + + case Q_ESIS: + b1 = gen_proto(ISO9542_ESIS, Q_ISO, Q_DEFAULT); + break; + + case Q_ISIS: + b1 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT); + break; + + case Q_ISIS_L1: /* all IS-IS Level1 PDU-Types */ + b0 = gen_proto(ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT); + b1 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */ + gen_or(b0, b1); + b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + break; + + case Q_ISIS_L2: /* all IS-IS Level2 PDU-Types */ + b0 = gen_proto(ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT); + b1 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */ + gen_or(b0, b1); + b0 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + b0 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + break; + + case Q_ISIS_IIH: /* all IS-IS Hello PDU-Types */ + b0 = gen_proto(ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT); + b1 = gen_proto(ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + b0 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + break; + + case Q_ISIS_LSP: + b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT); + b1 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + break; + + case Q_ISIS_SNP: + b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT); + b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + break; + + case Q_ISIS_CSNP: + b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT); + b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + break; + + case Q_ISIS_PSNP: + b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT); + b1 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT); + gen_or(b0, b1); + break; + + case Q_CLNP: + b1 = gen_proto(ISO8473_CLNP, Q_ISO, Q_DEFAULT); + break; + + case Q_STP: + b1 = gen_linktype(LLCSAP_8021D); + break; + + case Q_IPX: + b1 = gen_linktype(LLCSAP_IPX); + break; + + case Q_NETBEUI: + b1 = gen_linktype(LLCSAP_NETBEUI); + break; + default: abort(); } @@ -1483,12 +3243,29 @@ gen_port(port, ip_proto, dir) { struct block *b0, *b1, *tmp; - /* ether proto ip */ + /* + * ether proto ip + * + * For FDDI, RFC 1188 says that SNAP encapsulation is used, + * not LLC encapsulation with LLCSAP_IP. + * + * For IEEE 802 networks - which includes 802.5 token ring + * (which is what DLT_IEEE802 means) and 802.11 - RFC 1042 + * says that SNAP encapsulation is used, not LLC encapsulation + * with LLCSAP_IP. + * + * For LLC-encapsulated ATM/"Classical IP", RFC 1483 and + * RFC 2225 say that SNAP encapsulation is used, not LLC + * encapsulation with LLCSAP_IP. + * + * So we always check for ETHERTYPE_IP. + */ b0 = gen_linktype(ETHERTYPE_IP); switch (ip_proto) { case IPPROTO_UDP: case IPPROTO_TCP: + case IPPROTO_SCTP: b1 = gen_portop(port, ip_proto, dir); break; @@ -1496,6 +3273,8 @@ gen_port(port, ip_proto, dir) tmp = gen_portop(port, IPPROTO_TCP, dir); b1 = gen_portop(port, IPPROTO_UDP, dir); gen_or(tmp, b1); + tmp = gen_portop(port, IPPROTO_SCTP, dir); + gen_or(tmp, b1); break; default: @@ -1559,6 +3338,7 @@ gen_port6(port, ip_proto, dir) switch (ip_proto) { case IPPROTO_UDP: case IPPROTO_TCP: + case IPPROTO_SCTP: b1 = gen_portop6(port, ip_proto, dir); break; @@ -1566,6 +3346,8 @@ gen_port6(port, ip_proto, dir) tmp = gen_portop6(port, IPPROTO_TCP, dir); b1 = gen_portop6(port, IPPROTO_UDP, dir); gen_or(tmp, b1); + tmp = gen_portop6(port, IPPROTO_SCTP, dir); + gen_or(tmp, b1); break; default: @@ -1587,6 +3369,7 @@ lookup_proto(name, proto) case Q_DEFAULT: case Q_IP: + case Q_IPV6: v = pcap_nametoproto(name); if (v == PROTO_UNDEF) bpf_error("unknown ip proto '%s'", name); @@ -1599,6 +3382,17 @@ lookup_proto(name, proto) bpf_error("unknown ether proto '%s'", name); break; + case Q_ISO: + if (strcmp(name, "esis") == 0) + v = ISO9542_ESIS; + else if (strcmp(name, "isis") == 0) + v = ISO10589_ISIS; + else if (strcmp(name, "clnp") == 0) + v = ISO8473_CLNP; + else + bpf_error("unknown osi proto '%s'", name); + break; + default: v = PROTO_UNDEF; break; @@ -1630,7 +3424,6 @@ gen_protochain(v, proto, dir) int fix2, fix3, fix4, fix5; int ahcheck, again, end; int i, max; - int reg1 = alloc_reg(); int reg2 = alloc_reg(); memset(s, 0, sizeof(s)); @@ -1752,15 +3545,22 @@ gen_protochain(v, proto, dir) /* * in short, - * A = P[X + 1]; - * X = X + (P[X] + 1) * 8; + * A = P[X]; + * X = X + (P[X + 1] + 1) * 8; */ /* A = X */ s[i] = new_stmt(BPF_MISC|BPF_TXA); i++; - /* MEM[reg1] = A */ + /* A = P[X + packet head] */ + s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B); + s[i]->s.k = off_nl; + i++; + /* MEM[reg2] = A */ s[i] = new_stmt(BPF_ST); - s[i]->s.k = reg1; + s[i]->s.k = reg2; + i++; + /* A = X */ + s[i] = new_stmt(BPF_MISC|BPF_TXA); i++; /* A += 1 */ s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K); @@ -1773,18 +3573,6 @@ gen_protochain(v, proto, dir) s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B); s[i]->s.k = off_nl; i++; - /* MEM[reg2] = A */ - s[i] = new_stmt(BPF_ST); - s[i]->s.k = reg2; - i++; - /* X = MEM[reg1] */ - s[i] = new_stmt(BPF_LDX|BPF_MEM); - s[i]->s.k = reg1; - i++; - /* A = P[X + packet head] */ - s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B); - s[i]->s.k = off_nl; - i++; /* A += 1 */ s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K); s[i]->s.k = 1; @@ -1834,23 +3622,12 @@ gen_protochain(v, proto, dir) /* * in short, - * A = P[X + 1]; - * X = X + (P[X] + 2) * 4; + * A = P[X]; + * X = X + (P[X + 1] + 2) * 4; */ /* A = X */ s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA); i++; - /* MEM[reg1] = A */ - s[i] = new_stmt(BPF_ST); - s[i]->s.k = reg1; - i++; - /* A += 1 */ - s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K); - s[i]->s.k = 1; - i++; - /* X = A */ - s[i] = new_stmt(BPF_MISC|BPF_TAX); - i++; /* A = P[X + packet head]; */ s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B); s[i]->s.k = off_nl; @@ -1859,9 +3636,15 @@ gen_protochain(v, proto, dir) s[i] = new_stmt(BPF_ST); s[i]->s.k = reg2; i++; - /* X = MEM[reg1] */ - s[i] = new_stmt(BPF_LDX|BPF_MEM); - s[i]->s.k = reg1; + /* A = X */ + s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA); + i++; + /* A += 1 */ + s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K); + s[i]->s.k = 1; + i++; + /* X = A */ + s[i] = new_stmt(BPF_MISC|BPF_TAX); i++; /* A = P[X + packet head] */ s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B); @@ -1912,7 +3695,6 @@ gen_protochain(v, proto, dir) b->stmts = s[1]; /*remember, s[0] is dummy*/ b->s.k = v; - free_reg(reg1); free_reg(reg2); gen_and(b0, b); @@ -1942,6 +3724,21 @@ gen_proto(v, proto, dir) /*FALLTHROUGH*/ #endif case Q_IP: + /* + * For FDDI, RFC 1188 says that SNAP encapsulation is used, + * not LLC encapsulation with LLCSAP_IP. + * + * For IEEE 802 networks - which includes 802.5 token ring + * (which is what DLT_IEEE802 means) and 802.11 - RFC 1042 + * says that SNAP encapsulation is used, not LLC encapsulation + * with LLCSAP_IP. + * + * For LLC-encapsulated ATM/"Classical IP", RFC 1483 and + * RFC 2225 say that SNAP encapsulation is used, not LLC + * encapsulation with LLCSAP_IP. + * + * So we always check for ETHERTYPE_IP. + */ b0 = gen_linktype(ETHERTYPE_IP); #ifndef CHASE_CHAIN b1 = gen_cmp(off_nl + 9, BPF_B, (bpf_int32)v); @@ -1951,6 +3748,60 @@ gen_proto(v, proto, dir) gen_and(b0, b1); return b1; + case Q_ISO: + switch (linktype) { + + case DLT_FRELAY: + /* + * Frame Relay packets typically have an OSI + * NLPID at the beginning; "gen_linktype(LLCSAP_ISONS)" + * generates code to check for all the OSI + * NLPIDs, so calling it and then adding a check + * for the particular NLPID for which we're + * looking is bogus, as we can just check for + * the NLPID. + * + * What we check for is the NLPID and a frame + * control field value of UI, i.e. 0x03 followed + * by the NLPID. + * + * XXX - assumes a 2-byte Frame Relay header with + * DLCI and flags. What if the address is longer? + * + * XXX - what about SNAP-encapsulated frames? + */ + return gen_cmp(2, BPF_H, (0x03<<8) | v); + /*NOTREACHED*/ + break; + + case DLT_C_HDLC: + /* + * Cisco uses an Ethertype lookalike - for OSI, + * it's 0xfefe. + */ + b0 = gen_linktype(LLCSAP_ISONS<<8 | LLCSAP_ISONS); + /* OSI in C-HDLC is stuffed with a fudge byte */ + b1 = gen_cmp(off_nl_nosnap+1, BPF_B, (long)v); + gen_and(b0, b1); + return b1; + + default: + b0 = gen_linktype(LLCSAP_ISONS); + b1 = gen_cmp(off_nl_nosnap, BPF_B, (long)v); + gen_and(b0, b1); + return b1; + } + + case Q_ISIS: + b0 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT); + /* + * 4 is the offset of the PDU type relative to the IS-IS + * header. + */ + b1 = gen_cmp(off_nl_nosnap+4, BPF_B, (long)v); + gen_and(b0, b1); + return b1; + case Q_ARP: bpf_error("arp does not encapsulate another protocol"); /* NOTREACHED */ @@ -1994,6 +3845,10 @@ gen_proto(v, proto, dir) bpf_error("'tcp proto' is bogus"); /* NOTREACHED */ + case Q_SCTP: + bpf_error("'sctp proto' is bogus"); + /* NOTREACHED */ + case Q_ICMP: bpf_error("'icmp proto' is bogus"); /* NOTREACHED */ @@ -2010,6 +3865,10 @@ gen_proto(v, proto, dir) bpf_error("'pim proto' is bogus"); /* NOTREACHED */ + case Q_VRRP: + bpf_error("'vrrp proto' is bogus"); + /* NOTREACHED */ + #ifdef INET6 case Q_IPV6: b0 = gen_linktype(ETHERTYPE_IPV6); @@ -2028,8 +3887,17 @@ gen_proto(v, proto, dir) case Q_AH: bpf_error("'ah proto' is bogus"); - case Q_ESP: - bpf_error("'ah proto' is bogus"); + case Q_ESP: + bpf_error("'ah proto' is bogus"); + + case Q_STP: + bpf_error("'stp proto' is bogus"); + + case Q_IPX: + bpf_error("'ipx proto' is bogus"); + + case Q_NETBEUI: + bpf_error("'netbeui proto' is bogus"); default: abort(); @@ -2084,27 +3952,70 @@ gen_scode(name, q) if (eaddr == NULL) bpf_error( "unknown ether host '%s'", name); - return gen_ehostop(eaddr, dir); + b = gen_ehostop(eaddr, dir); + free(eaddr); + return b; case DLT_FDDI: eaddr = pcap_ether_hostton(name); if (eaddr == NULL) bpf_error( "unknown FDDI host '%s'", name); - return gen_fhostop(eaddr, dir); + b = gen_fhostop(eaddr, dir); + free(eaddr); + return b; case DLT_IEEE802: eaddr = pcap_ether_hostton(name); if (eaddr == NULL) bpf_error( "unknown token ring host '%s'", name); - return gen_thostop(eaddr, dir); + b = gen_thostop(eaddr, dir); + free(eaddr); + return b; + + case DLT_IEEE802_11: + eaddr = pcap_ether_hostton(name); + if (eaddr == NULL) + bpf_error( + "unknown 802.11 host '%s'", name); + b = gen_wlanhostop(eaddr, dir); + free(eaddr); + return b; + + case DLT_IP_OVER_FC: + eaddr = pcap_ether_hostton(name); + if (eaddr == NULL) + bpf_error( + "unknown Fibre Channel host '%s'", name); + b = gen_ipfchostop(eaddr, dir); + free(eaddr); + return b; + + case DLT_SUNATM: + if (!is_lane) + break; - default: - bpf_error( - "only ethernet/FDDI/token ring supports link-level host name"); - 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/Fibre Channel supports link-level host name"); } else if (proto == Q_DECNET) { unsigned short dn_addr = __pcap_nametodnaddr(name); /* @@ -2118,7 +4029,7 @@ gen_scode(name, q) if (alist == NULL || *alist == NULL) bpf_error("unknown host '%s'", name); tproto = proto; - if (off_linktype == -1 && tproto == Q_DEFAULT) + if (off_linktype == (u_int)-1 && tproto == Q_DEFAULT) tproto = Q_IP; b = gen_host(**alist++, 0xffffffff, tproto, dir); while (*alist) { @@ -2159,6 +4070,8 @@ gen_scode(name, q) tmp = gen_host6(&sin6->sin6_addr, &mask128, tproto6, dir); break; + default: + continue; } if (b) gen_or(b, tmp); @@ -2176,13 +4089,16 @@ gen_scode(name, q) } case Q_PORT: - if (proto != Q_DEFAULT && proto != Q_UDP && proto != Q_TCP) + if (proto != Q_DEFAULT && + proto != Q_UDP && proto != Q_TCP && proto != Q_SCTP) bpf_error("illegal qualifier of 'port'"); if (pcap_nametoport(name, &port, &real_proto) == 0) bpf_error("unknown port '%s'", name); if (proto == Q_UDP) { if (real_proto == IPPROTO_TCP) bpf_error("port '%s' is tcp", name); + else if (real_proto == IPPROTO_SCTP) + bpf_error("port '%s' is sctp", name); else /* override PROTO_UNDEF */ real_proto = IPPROTO_UDP; @@ -2190,10 +4106,23 @@ gen_scode(name, q) if (proto == Q_TCP) { if (real_proto == IPPROTO_UDP) bpf_error("port '%s' is udp", name); + + else if (real_proto == IPPROTO_SCTP) + bpf_error("port '%s' is sctp", name); else /* override PROTO_UNDEF */ real_proto = IPPROTO_TCP; } + if (proto == Q_SCTP) { + if (real_proto == IPPROTO_UDP) + bpf_error("port '%s' is udp", name); + + else if (real_proto == IPPROTO_TCP) + bpf_error("port '%s' is tcp", name); + else + /* override PROTO_UNDEF */ + real_proto = IPPROTO_SCTP; + } #ifndef INET6 return gen_port(port, real_proto, dir); #else @@ -2214,7 +4143,9 @@ gen_scode(name, q) alist = pcap_nametoaddr(name); if (alist == NULL || *alist == NULL) bpf_error("unknown host '%s'", name); - return gen_gateway(eaddr, alist, proto, dir); + b = gen_gateway(eaddr, alist, proto, dir); + free(eaddr); + return b; #else bpf_error("'gateway' not supported in this configuration"); #endif /*INET6*/ @@ -2281,6 +4212,7 @@ gen_mcode(s1, s2, masklen, q) bpf_error("Mask syntax for networks only"); /* NOTREACHED */ } + /* NOTREACHED */ } struct block * @@ -2331,6 +4263,8 @@ gen_ncode(s, v, q) proto = IPPROTO_UDP; else if (proto == Q_TCP) proto = IPPROTO_TCP; + else if (proto == Q_SCTP) + proto = IPPROTO_SCTP; else if (proto == Q_DEFAULT) proto = PROTO_UNDEF; else @@ -2393,6 +4327,7 @@ gen_mcode6(s1, s2, masklen, q) if (sizeof(mask) * 8 < masklen) bpf_error("mask length must be <= %u", (unsigned int)(sizeof(mask) * 8)); + memset(&mask, 0, sizeof(mask)); memset(&mask, 0xff, masklen / 8); if (masklen % 8) { mask.s6_addr[masklen / 8] = @@ -2431,6 +4366,8 @@ gen_ecode(eaddr, q) 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); @@ -2438,6 +4375,27 @@ gen_ecode(eaddr, q) 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) { + /* + * 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; + } + if (linktype == DLT_IP_OVER_FC) + return gen_ipfchostop(eaddr, (int)q.dir); + bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel"); } bpf_error("ethernet address used in non-ether expression"); /* NOTREACHED */ @@ -2511,6 +4469,14 @@ gen_load(proto, index, size) 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); @@ -2542,12 +4508,14 @@ gen_load(proto, index, size) index->b = b; break; + case Q_SCTP: case Q_TCP: case Q_UDP: case Q_ICMP: case Q_IGMP: case Q_IGRP: case Q_PIM: + case Q_VRRP: s = new_stmt(BPF_LDX|BPF_MSH|BPF_B); s->s.k = off_nl; sappend(s, xfer_to_a(index)); @@ -2590,16 +4558,16 @@ gen_relation(code, a0, a1, reversed) s0 = xfer_to_x(a1); s1 = xfer_to_a(a0); - s2 = new_stmt(BPF_ALU|BPF_SUB|BPF_X); - b = new_block(JMP(code)); - if (code == BPF_JGT || code == BPF_JGE) { - reversed = !reversed; - b->s.k = 0x80000000; + if (code == BPF_JEQ) { + s2 = new_stmt(BPF_ALU|BPF_SUB|BPF_X); + b = new_block(JMP(code)); + sappend(s1, s2); } + else + b = new_block(BPF_JMP|code|BPF_X); if (reversed) gen_not(b); - sappend(s1, s2); sappend(s0, s1); sappend(a1->s, s0); sappend(a0->s, a1->s); @@ -2697,6 +4665,7 @@ gen_arth(code, a0, a1) sappend(a1->s, s0); sappend(a0->s, a1->s); + free_reg(a0->regno); free_reg(a1->regno); s0 = new_stmt(BPF_ST); @@ -2766,6 +4735,9 @@ gen_greater(n) return gen_len(BPF_JGE, n); } +/* + * Actually, this is less than or equal. + */ struct block * gen_less(n) int n; @@ -2819,6 +4791,8 @@ gen_byteop(op, idx, val) return b; } +static u_char abroadcast[] = { 0x0 }; + struct block * gen_broadcast(proto) int proto; @@ -2831,12 +4805,34 @@ gen_broadcast(proto) 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) { + /* + * 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; @@ -2850,81 +4846,461 @@ gen_broadcast(proto) gen_and(b0, b2); return b2; } - bpf_error("only ether/ip broadcast filters supported"); + bpf_error("only link-layer/IP broadcast filters supported"); + /* NOTREACHED */ +} + +/* + * Generate code to test the low-order bit of a MAC address (that's + * the bottom bit of the *first* byte). + */ +static struct block * +gen_mac_multicast(offset) + int offset; +{ + register struct block *b0; + register struct slist *s; + + /* link[offset] & 1 != 0 */ + s = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = offset; + b0 = new_block(JMP(BPF_JSET)); + b0->s.k = 1; + b0->stmts = s; + return b0; +} + +struct block * +gen_multicast(proto) + int proto; +{ + register struct block *b0, *b1, *b2; + register struct slist *s; + + switch (proto) { + + 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 1; + 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 1; + 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 0; + 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 0; + 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 = new_stmt(BPF_LD|BPF_B|BPF_ABS); + s->s.k = 0; + 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) { + /* + * 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; + + case Q_IP: + b0 = gen_linktype(ETHERTYPE_IP); + b1 = gen_cmp(off_nl + 16, BPF_B, (bpf_int32)224); + b1->s.code = JMP(BPF_JGE); + gen_and(b0, b1); + return b1; + +#ifdef INET6 + case Q_IPV6: + b0 = gen_linktype(ETHERTYPE_IPV6); + b1 = gen_cmp(off_nl + 24, BPF_B, (bpf_int32)255); + gen_and(b0, b1); + return b1; +#endif /* INET6 */ + } + bpf_error("link-layer multicast filters supported only on ethernet/FDDI/token ring/ARCNET/802.11/ATM LANE/Fibre Channel"); + /* NOTREACHED */ +} + +/* + * generate command for inbound/outbound. It's here so we can + * make it link-type specific. 'dir' = 0 implies "inbound", + * = 1 implies "outbound". + */ +struct block * +gen_inbound(dir) + int dir; +{ + register struct block *b0; + + /* + * Only some data link types support inbound/outbound qualifiers. + */ + switch (linktype) { + case DLT_SLIP: + b0 = gen_relation(BPF_JEQ, + gen_load(Q_LINK, gen_loadi(0), 1), + gen_loadi(0), + dir); + break; + + case DLT_LINUX_SLL: + if (dir) { + /* + * Match packets sent by this machine. + */ + b0 = gen_cmp(0, BPF_H, LINUX_SLL_OUTGOING); + } else { + /* + * Match packets sent to this machine. + * (No broadcast or multicast packets, or + * packets sent to some other machine and + * received promiscuously.) + * + * XXX - packets sent to other machines probably + * shouldn't be matched, but what about broadcast + * or multicast packets we received? + */ + b0 = gen_cmp(0, BPF_H, LINUX_SLL_HOST); + } + break; + + case DLT_PFLOG: + b0 = gen_cmp(offsetof(struct pfloghdr, dir), BPF_B, + (bpf_int32)((dir == 0) ? PF_IN : PF_OUT)); + break; + + case DLT_PPP_WITHDIRECTION: + if (dir) { + /* match outgoing packets */ + b0 = gen_cmp(0, BPF_B, PPP_WITHDIRECTION_OUT); + } else { + /* match incoming packets */ + b0 = gen_cmp(0, BPF_B, PPP_WITHDIRECTION_IN); + } + break; + + case DLT_JUNIPER_MLPPP: + case DLT_JUNIPER_ATM1: + case DLT_JUNIPER_ATM2: + /* juniper flags (including direction) are stored + * the byte after the 3-byte magic number */ + if (dir) { + /* match outgoing packets */ + b0 = gen_mcmp(3, BPF_B, 0, 0x01); + } else { + /* match incoming packets */ + b0 = gen_mcmp(3, BPF_B, 1, 0x01); + } + break; + + default: + bpf_error("inbound/outbound not supported on linktype %d", + linktype); + b0 = NULL; + /* NOTREACHED */ + } + return (b0); +} + +/* PF firewall log matched interface */ +struct block * +gen_pf_ifname(const char *ifname) +{ + struct block *b0; + u_int len, off; + + if (linktype == DLT_PFLOG) { + len = sizeof(((struct pfloghdr *)0)->ifname); + off = offsetof(struct pfloghdr, ifname); + } else { + bpf_error("ifname not supported on linktype 0x%x", linktype); + /* NOTREACHED */ + } + if (strlen(ifname) >= len) { + bpf_error("ifname interface names can only be %d characters", + len-1); + /* NOTREACHED */ + } + b0 = gen_bcmp(off, strlen(ifname), (const u_char *)ifname); + return (b0); +} + +/* PF firewall log matched interface */ +struct block * +gen_pf_ruleset(char *ruleset) +{ + struct block *b0; + + if (linktype != DLT_PFLOG) { + bpf_error("ruleset not supported on linktype 0x%x", linktype); + /* NOTREACHED */ + } + if (strlen(ruleset) >= sizeof(((struct pfloghdr *)0)->ruleset)) { + bpf_error("ruleset names can only be %ld characters", + (long)(sizeof(((struct pfloghdr *)0)->ruleset) - 1)); + /* NOTREACHED */ + } + b0 = gen_bcmp(offsetof(struct pfloghdr, ruleset), + strlen(ruleset), (const u_char *)ruleset); + return (b0); +} + +/* PF firewall log rule number */ +struct block * +gen_pf_rnr(int rnr) +{ + struct block *b0; + + if (linktype == DLT_PFLOG) { + b0 = gen_cmp(offsetof(struct pfloghdr, rulenr), BPF_W, + (bpf_int32)rnr); + } else { + bpf_error("rnr not supported on linktype 0x%x", linktype); + /* NOTREACHED */ + } + + return (b0); +} + +/* PF firewall log sub-rule number */ +struct block * +gen_pf_srnr(int srnr) +{ + struct block *b0; + + if (linktype != DLT_PFLOG) { + bpf_error("srnr not supported on linktype 0x%x", linktype); + /* NOTREACHED */ + } + + b0 = gen_cmp(offsetof(struct pfloghdr, subrulenr), BPF_W, + (bpf_int32)srnr); + return (b0); +} + +/* PF firewall log reason code */ +struct block * +gen_pf_reason(int reason) +{ + struct block *b0; + + if (linktype == DLT_PFLOG) { + b0 = gen_cmp(offsetof(struct pfloghdr, reason), BPF_B, + (bpf_int32)reason); + } else { + bpf_error("reason not supported on linktype 0x%x", linktype); + /* NOTREACHED */ + } + + return (b0); } +/* PF firewall log action */ struct block * -gen_multicast(proto) - int proto; +gen_pf_action(int action) { - register struct block *b0, *b1; - register struct slist *s; + struct block *b0; - switch (proto) { + if (linktype == DLT_PFLOG) { + b0 = gen_cmp(offsetof(struct pfloghdr, action), BPF_B, + (bpf_int32)action); + } else { + bpf_error("action not supported on linktype 0x%x", linktype); + /* NOTREACHED */ + } - case Q_DEFAULT: - case Q_LINK: - if (linktype == DLT_EN10MB) { - /* ether[0] & 1 != 0 */ - s = new_stmt(BPF_LD|BPF_B|BPF_ABS); - s->s.k = 0; - b0 = new_block(JMP(BPF_JSET)); - b0->s.k = 1; - b0->stmts = s; - return b0; - } + return (b0); +} - if (linktype == DLT_FDDI) { - /* XXX TEST THIS: MIGHT NOT PORT PROPERLY XXX */ - /* fddi[1] & 1 != 0 */ - s = new_stmt(BPF_LD|BPF_B|BPF_ABS); - s->s.k = 1; - b0 = new_block(JMP(BPF_JSET)); - b0->s.k = 1; - b0->stmts = s; - return b0; - } +struct block * +gen_acode(eaddr, q) + register const u_char *eaddr; + struct qual q; +{ + if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK) { + if (linktype == DLT_ARCNET || linktype == DLT_ARCNET_LINUX) + return gen_ahostop(eaddr, (int)q.dir); + } + bpf_error("ARCnet address used in non-arc expression"); + /* NOTREACHED */ +} + +static struct block * +gen_ahostop(eaddr, dir) + register const u_char *eaddr; + register int dir; +{ + register struct block *b0, *b1; - /* TODO - check how token ring handles multicast */ - /* if (linktype == DLT_IEEE802) ... */ + switch (dir) { + /* src comes first, different from Ethernet */ + case Q_SRC: + return gen_bcmp(0, 1, eaddr); - /* Link not known to support multicasts */ - break; + case Q_DST: + return gen_bcmp(1, 1, eaddr); - case Q_IP: - b0 = gen_linktype(ETHERTYPE_IP); - b1 = gen_cmp(off_nl + 16, BPF_B, (bpf_int32)224); - b1->s.code = JMP(BPF_JGE); + case Q_AND: + b0 = gen_ahostop(eaddr, Q_SRC); + b1 = gen_ahostop(eaddr, Q_DST); gen_and(b0, b1); return b1; -#ifdef INET6 - case Q_IPV6: - b0 = gen_linktype(ETHERTYPE_IPV6); - b1 = gen_cmp(off_nl + 24, BPF_B, (bpf_int32)255); - gen_and(b0, b1); + case Q_DEFAULT: + case Q_OR: + b0 = gen_ahostop(eaddr, Q_SRC); + b1 = gen_ahostop(eaddr, Q_DST); + gen_or(b0, b1); return b1; -#endif /* INET6 */ } - bpf_error("only IP multicast filters supported on ethernet/FDDI"); -} - -/* - * generate command for inbound/outbound. It's here so we can - * make it link-type specific. 'dir' = 0 implies "inbound", - * = 1 implies "outbound". - */ -struct block * -gen_inbound(dir) - int dir; -{ - register struct block *b0; - - b0 = gen_relation(BPF_JEQ, - gen_load(Q_LINK, gen_loadi(0), 1), - gen_loadi(0), - dir); - return (b0); + abort(); + /* NOTREACHED */ } /* @@ -2934,7 +5310,6 @@ struct block * gen_vlan(vlan_num) int vlan_num; { - static u_int orig_linktype = -1, orig_nl = -1; struct block *b0; /* @@ -2944,11 +5319,13 @@ gen_vlan(vlan_num) if (orig_nl == (u_int)-1) { orig_linktype = off_linktype; /* save original values */ orig_nl = off_nl; + orig_nl_nosnap = off_nl_nosnap; switch (linktype) { case DLT_EN10MB: off_linktype = 16; + off_nl_nosnap = 18; off_nl = 18; break; @@ -2966,10 +5343,352 @@ gen_vlan(vlan_num) if (vlan_num >= 0) { struct block *b1; - b1 = gen_cmp(orig_nl, BPF_H, (bpf_int32)vlan_num); + b1 = gen_mcmp(orig_nl, BPF_H, (bpf_int32)vlan_num, 0x0fff); + gen_and(b0, b1); + b0 = b1; + } + + return (b0); +} + +/* + * support for MPLS + */ +struct block * +gen_mpls(label_num) + int label_num; +{ + struct block *b0; + + /* + * Change the offsets to point to the type and data fields within + * the MPLS packet. This is somewhat of a kludge. + */ + if (orig_nl == (u_int)-1) { + orig_linktype = off_linktype; /* save original values */ + orig_nl = off_nl; + orig_nl_nosnap = off_nl_nosnap; + + switch (linktype) { + + case DLT_EN10MB: + off_linktype = 16; + off_nl_nosnap = 18; + off_nl = 18; + + b0 = gen_cmp(orig_linktype, BPF_H, (bpf_int32)ETHERTYPE_MPLS); + break; + + case DLT_PPP: + off_linktype = 6; + off_nl_nosnap = 8; + off_nl = 8; + + b0 = gen_cmp(orig_linktype, BPF_H, (bpf_int32)PPP_MPLS_UCAST); + break; + + case DLT_C_HDLC: + off_linktype = 6; + off_nl_nosnap = 8; + off_nl = 8; + + b0 = gen_cmp(orig_linktype, BPF_H, (bpf_int32)ETHERTYPE_MPLS); + 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); + /*NOTREACHED*/ + } + } else { + bpf_error("'mpls' can't be combined with 'vlan' or another 'mpls'"); + /*NOTREACHED*/ + } + + /* 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(orig_nl, BPF_W, (bpf_int32)label_num, 0xfffff000); /* only compare the first 20 bits */ gen_and(b0, b1); b0 = b1; } return (b0); } + +struct block * +gen_atmfield_code(atmfield, jvalue, jtype, reverse) + int atmfield; + bpf_u_int32 jvalue; + bpf_u_int32 jtype; + int reverse; +{ + struct block *b0; + + switch (atmfield) { + + case A_VPI: + if (!is_atm) + bpf_error("'vpi' supported only on raw ATM"); + if (off_vpi == (u_int)-1) + abort(); + b0 = gen_ncmp(BPF_B, off_vpi, 0xffffffff, (u_int)jtype, + (u_int)jvalue, reverse); + break; + + case A_VCI: + if (!is_atm) + bpf_error("'vci' supported only on raw ATM"); + if (off_vci == (u_int)-1) + abort(); + b0 = gen_ncmp(BPF_H, off_vci, 0xffffffff, (u_int)jtype, + (u_int)jvalue, reverse); + break; + + case A_PROTOTYPE: + if (off_proto == (u_int)-1) + abort(); /* XXX - this isn't on FreeBSD */ + b0 = gen_ncmp(BPF_B, off_proto, 0x0f, (u_int)jtype, + (u_int)jvalue, reverse); + break; + + case A_MSGTYPE: + if (off_payload == (u_int)-1) + abort(); + b0 = gen_ncmp(BPF_B, off_payload + MSG_TYPE_POS, 0xffffffff, + (u_int)jtype, (u_int)jvalue, reverse); + break; + + case A_CALLREFTYPE: + if (!is_atm) + bpf_error("'callref' supported only on raw ATM"); + if (off_proto == (u_int)-1) + abort(); + b0 = gen_ncmp(BPF_B, off_proto, 0xffffffff, (u_int)jtype, + (u_int)jvalue, reverse); + break; + + default: + abort(); + } + return b0; +} + +struct block * +gen_atmtype_abbrev(type) + int type; +{ + struct block *b0, *b1; + + switch (type) { + + case A_METAC: + /* Get all packets in Meta signalling Circuit */ + if (!is_atm) + bpf_error("'metac' supported only on raw ATM"); + b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); + b1 = gen_atmfield_code(A_VCI, 1, BPF_JEQ, 0); + gen_and(b0, b1); + break; + + case A_BCC: + /* Get all packets in Broadcast Circuit*/ + if (!is_atm) + bpf_error("'bcc' supported only on raw ATM"); + b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); + b1 = gen_atmfield_code(A_VCI, 2, BPF_JEQ, 0); + gen_and(b0, b1); + break; + + case A_OAMF4SC: + /* Get all cells in Segment OAM F4 circuit*/ + if (!is_atm) + bpf_error("'oam4sc' supported only on raw ATM"); + b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); + b1 = gen_atmfield_code(A_VCI, 3, BPF_JEQ, 0); + gen_and(b0, b1); + break; + + case A_OAMF4EC: + /* Get all cells in End-to-End OAM F4 Circuit*/ + if (!is_atm) + bpf_error("'oam4ec' supported only on raw ATM"); + b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); + b1 = gen_atmfield_code(A_VCI, 4, BPF_JEQ, 0); + gen_and(b0, b1); + break; + + case A_SC: + /* Get all packets in connection Signalling Circuit */ + if (!is_atm) + bpf_error("'sc' supported only on raw ATM"); + b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); + b1 = gen_atmfield_code(A_VCI, 5, BPF_JEQ, 0); + gen_and(b0, b1); + break; + + case A_ILMIC: + /* Get all packets in ILMI Circuit */ + if (!is_atm) + bpf_error("'ilmic' supported only on raw ATM"); + b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); + b1 = gen_atmfield_code(A_VCI, 16, BPF_JEQ, 0); + gen_and(b0, b1); + break; + + case A_LANE: + /* Get all LANE packets */ + 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: + /* Get all LLC-encapsulated packets */ + 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: + abort(); + } + return b1; +} + + +static struct block * +gen_msg_abbrev(type) + int type; +{ + struct block *b1; + + /* + * Q.2931 signalling protocol messages for handling virtual circuits + * establishment and teardown + */ + switch (type) { + + case A_SETUP: + b1 = gen_atmfield_code(A_MSGTYPE, SETUP, BPF_JEQ, 0); + break; + + case A_CALLPROCEED: + b1 = gen_atmfield_code(A_MSGTYPE, CALL_PROCEED, BPF_JEQ, 0); + break; + + case A_CONNECT: + b1 = gen_atmfield_code(A_MSGTYPE, CONNECT, BPF_JEQ, 0); + break; + + case A_CONNECTACK: + b1 = gen_atmfield_code(A_MSGTYPE, CONNECT_ACK, BPF_JEQ, 0); + break; + + case A_RELEASE: + b1 = gen_atmfield_code(A_MSGTYPE, RELEASE, BPF_JEQ, 0); + break; + + case A_RELEASE_DONE: + b1 = gen_atmfield_code(A_MSGTYPE, RELEASE_DONE, BPF_JEQ, 0); + break; + + default: + abort(); + } + return b1; +} + +struct block * +gen_atmmulti_abbrev(type) + int type; +{ + struct block *b0, *b1; + + switch (type) { + + case A_OAM: + if (!is_atm) + bpf_error("'oam' supported only on raw ATM"); + b1 = gen_atmmulti_abbrev(A_OAMF4); + break; + + case A_OAMF4: + if (!is_atm) + bpf_error("'oamf4' supported only on raw ATM"); + /* OAM F4 type */ + b0 = gen_atmfield_code(A_VCI, 3, BPF_JEQ, 0); + b1 = gen_atmfield_code(A_VCI, 4, BPF_JEQ, 0); + gen_or(b0, b1); + b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); + gen_and(b0, b1); + break; + + case A_CONNECTMSG: + /* + * Get Q.2931 signalling messages for switched + * virtual connection + */ + if (!is_atm) + bpf_error("'connectmsg' supported only on raw ATM"); + b0 = gen_msg_abbrev(A_SETUP); + b1 = gen_msg_abbrev(A_CALLPROCEED); + gen_or(b0, b1); + b0 = gen_msg_abbrev(A_CONNECT); + gen_or(b0, b1); + b0 = gen_msg_abbrev(A_CONNECTACK); + gen_or(b0, b1); + b0 = gen_msg_abbrev(A_RELEASE); + gen_or(b0, b1); + b0 = gen_msg_abbrev(A_RELEASE_DONE); + gen_or(b0, b1); + b0 = gen_atmtype_abbrev(A_SC); + gen_and(b0, b1); + break; + + case A_METACONNECT: + if (!is_atm) + bpf_error("'metaconnect' supported only on raw ATM"); + b0 = gen_msg_abbrev(A_SETUP); + b1 = gen_msg_abbrev(A_CALLPROCEED); + gen_or(b0, b1); + b0 = gen_msg_abbrev(A_CONNECT); + gen_or(b0, b1); + b0 = gen_msg_abbrev(A_RELEASE); + gen_or(b0, b1); + b0 = gen_msg_abbrev(A_RELEASE_DONE); + gen_or(b0, b1); + b0 = gen_atmtype_abbrev(A_METAC); + gen_and(b0, b1); + break; + + default: + abort(); + } + return b1; +}