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-rw-r--r--usr.sbin/tcpdump/tcpdump/gencode.c1384
1 files changed, 0 insertions, 1384 deletions
diff --git a/usr.sbin/tcpdump/tcpdump/gencode.c b/usr.sbin/tcpdump/tcpdump/gencode.c
deleted file mode 100644
index 8cb48ea..0000000
--- a/usr.sbin/tcpdump/tcpdump/gencode.c
+++ /dev/null
@@ -1,1384 +0,0 @@
-/*
- * Copyright (c) 1990 The Regents of the University of California.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that: (1) source code distributions
- * retain the above copyright notice and this paragraph in its entirety, (2)
- * distributions including binary code include the above copyright notice and
- * this paragraph in its entirety in the documentation or other materials
- * provided with the distribution, and (3) all advertising materials mentioning
- * features or use of this software display the following acknowledgement:
- * ``This product includes software developed by the University of California,
- * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
- * the University nor the names of its contributors may be used to endorse
- * or promote products derived from this software without specific prior
- * written permission.
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
- */
-#ifndef lint
-static char rcsid[] =
- "@(#) $Header: gencode.c,v 1.33 92/05/22 16:38:39 mccanne Exp $ (LBL)";
-#endif
-
-#ifdef __STDC__
-#include <stdlib.h>
-#endif
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <net/if.h>
-#include <netinet/in.h>
-#include <netinet/if_ether.h>
-
-#include <sys/time.h>
-#include <net/bpf.h>
-
-#include "interface.h"
-#include "gencode.h"
-#include "nametoaddr.h"
-#include "extract.h"
-
-#define JMP(c) ((c)|BPF_JMP|BPF_K)
-
-extern struct bpf_insn *icode_to_fcode();
-extern u_long net_mask();
-static void init_linktype();
-
-static int alloc_reg();
-static void free_reg();
-
-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
- * goes into a library that would probably not be a good idea.
- */
-#define NCHUNKS 16
-#define CHUNK0SIZE 1024
-struct chunk {
- u_int n_left;
- void *m;
-};
-
-static struct chunk chunks[NCHUNKS];
-static int cur_chunk;
-
-static void *
-newchunk(n)
- u_int n;
-{
- struct chunk *cp;
- int k, size;
-
- /* XXX Round up to nearest long. */
- n = (n + sizeof(long) - 1) & ~(sizeof(long) - 1);
-
- cp = &chunks[cur_chunk];
- if (n > cp->n_left) {
- ++cp, k = ++cur_chunk;
- if (k >= NCHUNKS)
- error("out of memory");
- size = CHUNK0SIZE << k;
- cp->m = (void *)malloc(size);
- bzero((char *)cp->m, size);
- cp->n_left = size;
- if (n > size)
- error("out of memory");
- }
- cp->n_left -= n;
- return (void *)((char *)cp->m + cp->n_left);
-}
-
-static void
-freechunks()
-{
- int i;
-
- for (i = 0; i < NCHUNKS; ++i)
- if (chunks[i].m)
- free(chunks[i].m);
-}
-
-static inline struct block *
-new_block(code)
- int code;
-{
- struct block *p;
-
- p = (struct block *)newchunk(sizeof(*p));
- p->s.code = code;
- p->head = p;
-
- return p;
-}
-
-static inline struct slist *
-new_stmt(code)
- int code;
-{
- struct slist *p;
-
- p = (struct slist *)newchunk(sizeof(*p));
- p->s.code = code;
-
- return p;
-}
-
-static struct block *
-gen_retblk(v)
- int v;
-{
- struct block *b = new_block(BPF_RET|BPF_K);
-
- b->s.k = v;
- return b;
-}
-
-static inline void
-syntax()
-{
- error("syntax error in filter expression");
-}
-
-static u_long netmask;
-
-struct bpf_program *
-parse(buf, Oflag, linktype, mask)
- char *buf;
- int Oflag;
- int linktype;
- u_long mask;
-{
- extern int n_errors;
- static struct bpf_program F;
- struct bpf_insn *p;
- int len;
-
- netmask = mask;
-
- F.bf_insns = 0;
- F.bf_len = 0;
-
- lex_init(buf ? buf : "");
- init_linktype(linktype);
- yyparse();
-
- if (n_errors)
- syntax();
-
- if (root == 0)
- root = gen_retblk(snaplen);
-
- if (Oflag) {
- optimize(&root);
- if (root == 0 ||
- (root->s.code == (BPF_RET|BPF_K) && root->s.k == 0))
- error("expression rejects all packets");
- }
- p = icode_to_fcode(root, &len);
- F.bf_insns = p;
- F.bf_len = len;
-
- freechunks();
- return &F;
-}
-
-/*
- * Backpatch the blocks in 'list' to 'target'. The 'sense' field indicates
- * which of the jt and jf fields has been resolved and which is a pointer
- * back to another unresolved block (or nil). At least one of the fields
- * in each block is already resolved.
- */
-static void
-backpatch(list, target)
- struct block *list, *target;
-{
- struct block *next;
-
- while (list) {
- if (!list->sense) {
- next = JT(list);
- JT(list) = target;
- } else {
- next = JF(list);
- JF(list) = target;
- }
- list = next;
- }
-}
-
-/*
- * Merge the lists in b0 and b1, using the 'sense' field to indicate
- * which of jt and jf is the link.
- */
-static void
-merge(b0, b1)
- struct block *b0, *b1;
-{
- register struct block **p = &b0;
-
- /* Find end of list. */
- while (*p)
- p = !((*p)->sense) ? &JT(*p) : &JF(*p);
-
- /* Concatenate the lists. */
- *p = b1;
-}
-
-void
-finish_parse(p)
- struct block *p;
-{
- backpatch(p, gen_retblk(snaplen));
- p->sense = !p->sense;
- backpatch(p, gen_retblk(0));
- root = p->head;
-}
-
-void
-gen_and(b0, b1)
- struct block *b0, *b1;
-{
- backpatch(b0, b1->head);
- b0->sense = !b0->sense;
- b1->sense = !b1->sense;
- merge(b1, b0);
- b1->sense = !b1->sense;
- b1->head = b0->head;
-}
-
-void
-gen_or(b0, b1)
- struct block *b0, *b1;
-{
- b0->sense = !b0->sense;
- backpatch(b0, b1->head);
- b0->sense = !b0->sense;
- merge(b1, b0);
- b1->head = b0->head;
-}
-
-void
-gen_not(b)
- struct block *b;
-{
- b->sense = !b->sense;
-}
-
-static struct block *
-gen_cmp(offset, size, v)
- u_int offset, size;
- long v;
-{
- struct slist *s;
- struct block *b;
-
- s = new_stmt(BPF_LD|BPF_ABS|size);
- s->s.k = offset;
-
- b = new_block(JMP(BPF_JEQ));
- b->stmts = s;
- b->s.k = v;
-
- return b;
-}
-
-struct block *
-gen_mcmp(offset, size, v, mask)
- u_int offset, size;
- long v;
- u_long mask;
-{
- struct block *b = gen_cmp(offset, size, v);
- struct slist *s;
-
- if (mask != 0xffffffff) {
- s = new_stmt(BPF_ALU|BPF_AND|BPF_K);
- s->s.k = mask;
- b->stmts->next = s;
- }
- return b;
-}
-
-struct block *
-gen_bcmp(offset, size, v)
- u_int offset;
- u_int size;
- u_char *v;
-{
- struct block *b, *tmp;
- int k;
-
- b = 0;
- while (size >= 4) {
- k = size - 4;
- tmp = gen_cmp(offset + k, BPF_W, EXTRACT_LONG(&v[k]));
- if (b != 0)
- gen_and(b, tmp);
- b = tmp;
- size -= 4;
- }
- while (size >= 2) {
- k = size - 2;
- tmp = gen_cmp(offset + k, BPF_H, (long)EXTRACT_SHORT(&v[k]));
- if (b != 0)
- gen_and(b, tmp);
- b = tmp;
- size -= 2;
- }
- if (size > 0) {
- tmp = gen_cmp(offset, BPF_B, (long)v[0]);
- if (b != 0)
- gen_and(b, tmp);
- b = tmp;
- }
- return b;
-}
-
-/*
- * Various code contructs 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.
- */
-static u_int off_linktype;
-static u_int off_nl;
-static int linktype;
-
-static void
-init_linktype(type)
- int type;
-{
- linktype = type;
-
- switch (type) {
-
- case DLT_EN10MB:
- off_linktype = 12;
- off_nl = 14;
- return;
-
- case DLT_SLIP:
- /*
- * SLIP doesn't have a link level type. The 16 byte
- * header is hacked into our SLIP driver.
- */
- off_linktype = -1;
- off_nl = 16;
- return;
-
- case DLT_NULL:
- off_linktype = -1;
- off_nl = 0;
- return;
-
- case DLT_PPP:
- off_linktype = 2;
- off_nl = 4;
- return;
-
- case DLT_FDDI:
- off_linktype = 19;
- off_nl = 21;
- return;
-
- case DLT_IEEE802:
- off_linktype = 20;
- off_nl = 22;
- return;
- }
- error("unknown data link type 0x%x", linktype);
- /* NOTREACHED */
-}
-
-static struct block *
-gen_uncond(rsense)
- int rsense;
-{
- struct block *b;
- struct slist *s;
-
- s = new_stmt(BPF_LD|BPF_IMM);
- s->s.k = !rsense;
- b = new_block(JMP(BPF_JEQ));
- b->stmts = s;
-
- return b;
-}
-
-static inline struct block *
-gen_true()
-{
- return gen_uncond(1);
-}
-
-static inline struct block *
-gen_false()
-{
- return gen_uncond(0);
-}
-
-struct block *
-gen_linktype(proto)
- int proto;
-{
- switch (linktype) {
- case DLT_SLIP:
- if (proto == ETHERTYPE_IP)
- return gen_true();
- else
- return gen_false();
-
- case DLT_PPP:
- if (proto == ETHERTYPE_IP)
- proto = 0x0021; /* XXX - need ppp.h defs */
- break;
- }
- return gen_cmp(off_linktype, BPF_H, (long)proto);
-}
-
-static struct block *
-gen_hostop(addr, mask, dir, proto, src_off, dst_off)
- u_long addr;
- u_long mask;
- int dir, proto;
- u_int src_off, dst_off;
-{
- struct block *b0, *b1;
- u_int offset;
-
- switch (dir) {
-
- case Q_SRC:
- offset = src_off;
- break;
-
- case Q_DST:
- offset = dst_off;
- break;
-
- case Q_AND:
- b0 = gen_hostop(addr, mask, Q_SRC, proto, src_off, dst_off);
- b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off);
- gen_and(b0, b1);
- return b1;
-
- case Q_OR:
- case Q_DEFAULT:
- b0 = gen_hostop(addr, mask, Q_SRC, proto, src_off, dst_off);
- b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off);
- gen_or(b0, b1);
- return b1;
-
- default:
- abort();
- }
- b0 = gen_linktype(proto);
- b1 = gen_mcmp(offset, BPF_W, (long)addr, mask);
- gen_and(b0, b1);
- return b1;
-}
-
-static struct block *
-gen_ehostop(eaddr, dir)
- u_char *eaddr;
- int dir;
-{
- struct block *b0, *b1;
-
- switch (dir) {
- case Q_SRC:
- return gen_bcmp(6, 6, eaddr);
-
- case Q_DST:
- return gen_bcmp(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 */
-}
-
-static struct block *
-gen_host(addr, mask, proto, dir)
- u_long addr;
- u_long mask;
- int proto;
- int dir;
-{
- struct block *b0, *b1;
-
- switch (proto) {
-
- case Q_DEFAULT:
- b0 = gen_host(addr, mask, Q_IP, dir);
- b1 = gen_host(addr, mask, Q_ARP, dir);
- gen_or(b0, b1);
- b0 = gen_host(addr, mask, Q_RARP, dir);
- gen_or(b1, b0);
- return b0;
-
- case Q_IP:
- return gen_hostop(addr, mask, dir, ETHERTYPE_IP,
- off_nl + 12, off_nl + 16);
-
- case Q_RARP:
- return gen_hostop(addr, mask, dir, ETHERTYPE_REVARP,
- off_nl + 14, off_nl + 24);
-
- case Q_ARP:
- return gen_hostop(addr, mask, dir, ETHERTYPE_ARP,
- off_nl + 14, off_nl + 24);
-
- case Q_TCP:
- error("'tcp' modifier applied to host");
-
- case Q_UDP:
- error("'udp' modifier applied to host");
-
- case Q_ICMP:
- error("'icmp' modifier applied to host");
- }
- abort();
- /* NOTREACHED */
-}
-
-static struct block *
-gen_gateway(eaddr, alist, proto, dir)
- u_char *eaddr;
- u_long **alist;
- int proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- if (dir != 0)
- error("direction applied to 'gateway'");
-
- switch (proto) {
- case Q_DEFAULT:
- case Q_IP:
- case Q_ARP:
- case Q_RARP:
- b0 = gen_ehostop(eaddr, Q_OR);
- b1 = gen_host(**alist++, 0xffffffffL, proto, Q_OR);
- while (*alist) {
- tmp = gen_host(**alist++, 0xffffffffL, proto, Q_OR);
- gen_or(b1, tmp);
- b1 = tmp;
- }
- gen_not(b1);
- gen_and(b0, b1);
- return b1;
- }
- error("illegal modifier of 'gateway'");
- /* NOTREACHED */
-}
-
-struct block *
-gen_proto_abbrev(proto)
- int proto;
-{
- struct block *b0, *b1;
-
- switch (proto) {
-
- case Q_TCP:
- b0 = gen_linktype(ETHERTYPE_IP);
- b1 = gen_cmp(off_nl + 9, BPF_B, (long)IPPROTO_TCP);
- gen_and(b0, b1);
- break;
-
- case Q_UDP:
- b0 = gen_linktype(ETHERTYPE_IP);
- b1 = gen_cmp(off_nl + 9, BPF_B, (long)IPPROTO_UDP);
- gen_and(b0, b1);
- break;
-
- case Q_ICMP:
- b0 = gen_linktype(ETHERTYPE_IP);
- b1 = gen_cmp(off_nl + 9, BPF_B, (long)IPPROTO_ICMP);
- gen_and(b0, b1);
- break;
-
- case Q_IP:
- b1 = gen_linktype(ETHERTYPE_IP);
- break;
-
- case Q_ARP:
- b1 = gen_linktype(ETHERTYPE_ARP);
- break;
-
- case Q_RARP:
- b1 = gen_linktype(ETHERTYPE_REVARP);
- break;
-
- case Q_LINK:
- error("link layer applied in wrong context");
-
- default:
- abort();
- }
- return b1;
-}
-
-static struct block *
-gen_ipfrag()
-{
- struct slist *s;
- struct block *b;
-
- /* not ip frag */
- s = new_stmt(BPF_LD|BPF_H|BPF_ABS);
- s->s.k = off_nl + 6;
- b = new_block(JMP(BPF_JSET));
- b->s.k = 0x1fff;
- b->stmts = s;
- gen_not(b);
-
- return b;
-}
-
-static struct block *
-gen_portatom(off, v)
- int off;
- long v;
-{
- struct slist *s;
- struct block *b;
-
- s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
- s->s.k = off_nl;
-
- s->next = new_stmt(BPF_LD|BPF_IND|BPF_H);
- s->next->s.k = off_nl + off;
-
- b = new_block(JMP(BPF_JEQ));
- b->stmts = s;
- b->s.k = v;
-
- return b;
-}
-
-struct block *
-gen_portop(port, proto, dir)
- int port;
- int proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- /* ip proto 'proto' */
- tmp = gen_cmp(off_nl + 9, BPF_B, (long)proto);
- b0 = gen_ipfrag();
- gen_and(tmp, b0);
-
- switch (dir) {
- case Q_SRC:
- b1 = gen_portatom(0, (long)port);
- break;
-
- case Q_DST:
- b1 = gen_portatom(2, (long)port);
- break;
-
- case Q_OR:
- case Q_DEFAULT:
- tmp = gen_portatom(0, (long)port);
- b1 = gen_portatom(2, (long)port);
- gen_or(tmp, b1);
- break;
-
- case Q_AND:
- tmp = gen_portatom(0, (long)port);
- b1 = gen_portatom(2, (long)port);
- gen_and(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
-
- return b1;
-}
-
-static struct block *
-gen_port(port, ip_proto, dir)
- int port;
- int ip_proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- /* ether proto ip */
- b0 = gen_linktype(ETHERTYPE_IP);
-
- switch (ip_proto) {
- case IPPROTO_UDP:
- case IPPROTO_TCP:
- b1 = gen_portop(port, ip_proto, dir);
- break;
-
- case PROTO_UNDEF:
- tmp = gen_portop(port, IPPROTO_TCP, dir);
- b1 = gen_portop(port, IPPROTO_UDP, dir);
- gen_or(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
- return b1;
-}
-
-int
-lookup_proto(name, proto)
- char *name;
- int proto;
-{
- int v;
-
- switch (proto) {
- case Q_DEFAULT:
- case Q_IP:
- v = s_nametoproto(name);
- if (v == PROTO_UNDEF)
- error("unknown ip proto '%s'", name);
- break;
-
- case Q_LINK:
- /* XXX should look up h/w protocol type based on linktype */
- v = s_nametoeproto(name);
- if (v == PROTO_UNDEF)
- error("unknown ether proto '%s'", name);
- break;
-
- default:
- v = PROTO_UNDEF;
- break;
- }
- return v;
-}
-
-struct block *
-gen_proto(v, proto, dir)
- int v;
- int proto;
- int dir;
-{
- struct block *b0, *b1;
-
- if (dir != Q_DEFAULT)
- error("direction applied to 'proto'");
-
- switch (proto) {
- case Q_DEFAULT:
- case Q_IP:
- b0 = gen_linktype(ETHERTYPE_IP);
- b1 = gen_cmp(off_nl + 9, BPF_B, (long)v);
- gen_and(b0, b1);
- return b1;
-
- case Q_ARP:
- error("arp does not encapsulate another protocol");
- /* NOTREACHED */
-
- case Q_RARP:
- error("rarp does not encapsulate another protocol");
- /* NOTREACHED */
-
- case Q_LINK:
- return gen_linktype(v);
-
- case Q_UDP:
- error("'udp proto' is bogus");
-
- case Q_TCP:
- error("'tcp proto' is bogus");
-
- case Q_ICMP:
- error("'icmp proto' is bogus");
- }
- abort();
- /* NOTREACHED */
-}
-
-struct block *
-gen_scode(name, q)
- char *name;
- struct qual q;
-{
- int proto = q.proto;
- int dir = q.dir;
- u_char *eaddr;
- u_long mask, addr, **alist;
- struct block *b, *tmp;
- int port, real_proto;
-
- switch (q.addr) {
-
- case Q_NET:
- addr = s_nametonetaddr(name);
- if (addr == 0)
- error("unknown network '%s'", name);
- mask = net_mask(&addr);
- return gen_host(addr, mask, proto, dir);
-
- case Q_DEFAULT:
- case Q_HOST:
- if (proto == Q_LINK) {
- /* XXX Should lookup hw addr based on link layer */
- eaddr = ETHER_hostton(name);
- if (eaddr == 0)
- error("unknown ether host '%s'", name);
- return gen_ehostop(eaddr, dir);
-
- } else {
- alist = s_nametoaddr(name);
- if (alist == 0 || *alist == 0)
- error("uknown host '%s'", name);
- b = gen_host(**alist++, 0xffffffffL, proto, dir);
- while (*alist) {
- tmp = gen_host(**alist++, 0xffffffffL,
- proto, dir);
- gen_or(b, tmp);
- b = tmp;
- }
- return b;
- }
-
- case Q_PORT:
- if (proto != Q_DEFAULT && proto != Q_UDP && proto != Q_TCP)
- error("illegal qualifier of 'port'");
- if (s_nametoport(name, &port, &real_proto) == 0)
- error("unknown port '%s'", name);
- if (proto == Q_UDP) {
- if (real_proto == IPPROTO_TCP)
- error("port '%s' is tcp", name);
- else
- /* override PROTO_UNDEF */
- real_proto = IPPROTO_UDP;
- }
- if (proto == Q_TCP) {
- if (real_proto == IPPROTO_UDP)
- error("port '%s' is udp", name);
- else
- /* override PROTO_UNDEF */
- real_proto = IPPROTO_TCP;
- }
- return gen_port(port, real_proto, dir);
-
- case Q_GATEWAY:
- eaddr = ETHER_hostton(name);
- if (eaddr == 0)
- error("unknown ether host: %s", name);
-
- alist = s_nametoaddr(name);
- if (alist == 0 || *alist == 0)
- error("uknown host '%s'", name);
- return gen_gateway(eaddr, alist, proto, dir);
-
- case Q_PROTO:
- real_proto = lookup_proto(name, proto);
- if (real_proto >= 0)
- return gen_proto(real_proto, proto, dir);
- else
- error("unknown protocol: %s", name);
-
- case Q_UNDEF:
- syntax();
- /* NOTREACHED */
- }
- abort();
- /* NOTREACHED */
-}
-
-struct block *
-gen_ncode(v, q)
- u_long v;
- struct qual q;
-{
- u_long mask;
- int proto = q.proto;
- int dir = q.dir;
-
- switch (q.addr) {
-
- case Q_DEFAULT:
- case Q_HOST:
- case Q_NET:
- mask = net_mask(&v);
- return gen_host(v, mask, proto, dir);
-
- case Q_PORT:
- if (proto == Q_UDP)
- proto = IPPROTO_UDP;
- else if (proto == Q_TCP)
- proto = IPPROTO_TCP;
- else if (proto == Q_DEFAULT)
- proto = PROTO_UNDEF;
- else
- error("illegal qualifier of 'port'");
-
- return gen_port((int)v, proto, dir);
-
- case Q_GATEWAY:
- error("'gateway' requires a name");
- /* NOTREACHED */
-
- case Q_PROTO:
- return gen_proto((int)v, proto, dir);
-
- case Q_UNDEF:
- syntax();
- /* NOTREACHED */
- }
- abort();
- /* NOTREACHED */
-}
-
-struct block *
-gen_ecode(eaddr, q)
- u_char *eaddr;
- struct qual q;
-{
- if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK)
- return gen_ehostop(eaddr, (int)q.dir);
- else
- error("ethernet address used in non-ether expression");
- /* NOTREACHED */
-}
-
-void
-sappend(s0, s1)
- struct slist *s0, *s1;
-{
- /*
- * This is definitely not the best way to do this, but the
- * lists will rarely get long.
- */
- while (s0->next)
- s0 = s0->next;
- s0->next = s1;
-}
-
-struct slist *
-xfer_to_x(a)
- struct arth *a;
-{
- struct slist *s;
-
- s = new_stmt(BPF_LDX|BPF_MEM);
- s->s.k = a->regno;
- return s;
-}
-
-struct slist *
-xfer_to_a(a)
- struct arth *a;
-{
- struct slist *s;
-
- s = new_stmt(BPF_LD|BPF_MEM);
- s->s.k = a->regno;
- return s;
-}
-
-struct arth *
-gen_load(proto, index, size)
- int proto;
- struct arth *index;
- int size;
-{
- struct slist *s, *tmp;
- struct block *b;
- int regno = alloc_reg();
-
- free_reg(index->regno);
- switch (size) {
-
- default:
- error("data size must be 1, 2, or 4");
-
- case 1:
- size = BPF_B;
- break;
-
- case 2:
- size = BPF_H;
- break;
-
- case 4:
- size = BPF_W;
- break;
- }
- switch (proto) {
- default:
- error("unsupported index operation");
-
- case Q_LINK:
- s = xfer_to_x(index);
- tmp = new_stmt(BPF_LD|BPF_IND|size);
- sappend(s, tmp);
- sappend(index->s, s);
- break;
-
- case Q_IP:
- case Q_ARP:
- case Q_RARP:
- /* XXX Note that we assume a fixed link link header here. */
- s = xfer_to_x(index);
- tmp = new_stmt(BPF_LD|BPF_IND|size);
- tmp->s.k = off_nl;
- sappend(s, tmp);
- sappend(index->s, s);
-
- b = gen_proto_abbrev(proto);
- if (index->b)
- gen_and(index->b, b);
- index->b = b;
- break;
-
- case Q_TCP:
- case Q_UDP:
- case Q_ICMP:
- s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
- s->s.k = off_nl;
- sappend(s, xfer_to_a(index));
- sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
- sappend(s, new_stmt(BPF_MISC|BPF_TAX));
- sappend(s, tmp = new_stmt(BPF_LD|BPF_IND|size));
- tmp->s.k = off_nl;
- sappend(index->s, s);
-
- gen_and(gen_proto_abbrev(proto), b = gen_ipfrag());
- if (index->b)
- gen_and(index->b, b);
- index->b = b;
- break;
- }
- index->regno = regno;
- s = new_stmt(BPF_ST);
- s->s.k = regno;
- sappend(index->s, s);
-
- return index;
-}
-
-struct block *
-gen_relation(code, a0, a1, reversed)
- int code;
- struct arth *a0, *a1;
- int reversed;
-{
- struct slist *s0, *s1, *s2;
- struct block *b, *tmp;
-
- 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 (reversed)
- gen_not(b);
-
- sappend(s1, s2);
- sappend(s0, s1);
- sappend(a1->s, s0);
- sappend(a0->s, a1->s);
-
- b->stmts = a0->s;
-
- free_reg(a0->regno);
- free_reg(a1->regno);
-
- /* 'and' together protocol checks */
- if (a0->b) {
- if (a1->b) {
- gen_and(a0->b, tmp = a1->b);
- }
- else
- tmp = a0->b;
- } else
- tmp = a1->b;
-
- if (tmp)
- gen_and(tmp, b);
-
- return b;
-}
-
-struct arth *
-gen_loadlen()
-{
- int regno = alloc_reg();
- struct arth *a = (struct arth *)newchunk(sizeof(*a));
- struct slist *s;
-
- s = new_stmt(BPF_LD|BPF_LEN);
- s->next = new_stmt(BPF_ST);
- s->next->s.k = regno;
- a->s = s;
- a->regno = regno;
-
- return a;
-}
-
-struct arth *
-gen_loadi(val)
- int val;
-{
- struct arth *a;
- struct slist *s;
- int reg;
-
- a = (struct arth *)newchunk(sizeof(*a));
-
- reg = alloc_reg();
-
- s = new_stmt(BPF_LD|BPF_IMM);
- s->s.k = val;
- s->next = new_stmt(BPF_ST);
- s->next->s.k = reg;
- a->s = s;
- a->regno = reg;
-
- return a;
-}
-
-struct arth *
-gen_neg(a)
- struct arth *a;
-{
- struct slist *s;
-
- s = xfer_to_a(a);
- sappend(a->s, s);
- s = new_stmt(BPF_ALU|BPF_NEG);
- s->s.k = 0;
- sappend(a->s, s);
- s = new_stmt(BPF_ST);
- s->s.k = a->regno;
- sappend(a->s, s);
-
- return a;
-}
-
-struct arth *
-gen_arth(code, a0, a1)
- int code;
- struct arth *a0, *a1;
-{
- struct slist *s0, *s1, *s2;
-
- s0 = xfer_to_x(a1);
- s1 = xfer_to_a(a0);
- s2 = new_stmt(BPF_ALU|BPF_X|code);
-
- sappend(s1, s2);
- sappend(s0, s1);
- sappend(a1->s, s0);
- sappend(a0->s, a1->s);
-
- free_reg(a1->regno);
-
- s0 = new_stmt(BPF_ST);
- a0->regno = s0->s.k = alloc_reg();
- sappend(a0->s, s0);
-
- return a0;
-}
-
-/*
- * Here we handle simple allocation of the scratch registers.
- * If too many registers are alloc'd, the allocator punts.
- */
-static int regused[BPF_MEMWORDS];
-static int curreg;
-
-/*
- * Return the next free register.
- */
-static int
-alloc_reg()
-{
- int n = BPF_MEMWORDS;
-
- while (--n >= 0) {
- if (regused[curreg])
- curreg = (curreg + 1) % BPF_MEMWORDS;
- else {
- regused[curreg] = 1;
- return curreg;
- }
- }
- error("too many registers needed to evaluate expression");
- /* NOTREACHED */
-}
-
-/*
- * Return a register to the table so it can
- * be used later.
- */
-static void
-free_reg(n)
- int n;
-{
- regused[n] = 0;
-}
-
-static struct block *
-gen_len(jmp, n)
- int jmp;
- int n;
-{
- struct slist *s;
- struct block *b;
-
- s = new_stmt(BPF_LD|BPF_LEN);
- s->next = new_stmt(BPF_SUB|BPF_IMM);
- s->next->s.k = n;
- b = new_block(JMP(jmp));
- b->stmts = s;
-
- return b;
-}
-
-struct block *
-gen_greater(n)
- int n;
-{
- return gen_len(BPF_JGE, n);
-}
-
-struct block *
-gen_less(n)
- int n;
-{
- struct block *b;
-
- b = gen_len(BPF_JGT, n);
- gen_not(b);
-
- return b;
-}
-
-struct block *
-gen_byteop(op, idx, val)
- int op;
- int idx;
- int val;
-{
- struct block *b;
- struct slist *s;
-
- switch (op) {
- default:
- abort();
-
- case '=':
- return gen_cmp((u_int)idx, BPF_B, (long)val);
-
- case '<':
- b = gen_cmp((u_int)idx, BPF_B, (long)val);
- b->s.code = JMP(BPF_JGE);
- gen_not(b);
- return b;
-
- case '>':
- b = gen_cmp((u_int)idx, BPF_B, (long)val);
- b->s.code = JMP(BPF_JGT);
- return b;
-
- case '|':
- s = new_stmt(BPF_ALU|BPF_AND|BPF_K);
- break;
-
- case '&':
- s = new_stmt(BPF_ALU|BPF_AND|BPF_K);
- break;
- }
- s->s.k = val;
- b = new_block(JMP(BPF_JEQ));
- b->stmts = s;
- gen_not(b);
-
- return b;
-}
-
-struct block *
-gen_broadcast(proto)
- int proto;
-{
- u_long hostmask;
- struct block *b0, *b1, *b2;
- static u_char ebroadcast[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
-
- switch (proto) {
-
- case Q_DEFAULT:
- case Q_LINK:
- if (linktype == DLT_EN10MB)
- return gen_ehostop(ebroadcast, Q_DST);
- error("not a broadcast link");
- break;
-
- case Q_IP:
- b0 = gen_linktype(ETHERTYPE_IP);
- hostmask = ~netmask;
- b1 = gen_mcmp(off_nl + 16, BPF_W, (long)0, hostmask);
- b2 = gen_mcmp(off_nl + 16, BPF_W,
- (long)(~0 & hostmask), hostmask);
- gen_or(b1, b2);
- gen_and(b0, b2);
- return b2;
- }
- error("only ether/ip broadcast filters supported");
-}
-
-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_EN10MB)
- break;
-
- /* 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;
-
- case Q_IP:
- b0 = gen_linktype(ETHERTYPE_IP);
- b1 = gen_cmp(off_nl + 16, BPF_B, (long)224);
- b1->s.code = JMP(BPF_JGE);
- gen_and(b0, b1);
- return b1;
- }
- error("only ether/ip multicast filters supported");
-}
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