add initial support for the crisarchitecture used on foxboards to openwrt
[openwrt/svn-archive/archive.git] / target / linux / etrax-2.6 / image / e100boot / src / libpcap-0.4 / bpf / net / bpf_filter.c
diff --git a/target/linux/etrax-2.6/image/e100boot/src/libpcap-0.4/bpf/net/bpf_filter.c b/target/linux/etrax-2.6/image/e100boot/src/libpcap-0.4/bpf/net/bpf_filter.c
new file mode 100644 (file)
index 0000000..d3dcc68
--- /dev/null
@@ -0,0 +1,532 @@
+/*-
+ * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
+ *     The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from the Stanford/CMU enet packet filter,
+ * (net/enet.c) distributed as part of 4.3BSD, and code contributed
+ * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 
+ * Berkeley Laboratory.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *     This product includes software developed by the University of
+ *     California, Berkeley and its contributors.
+ * 4. 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 BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *     @(#)bpf.c       7.5 (Berkeley) 7/15/91
+ */
+
+#if !(defined(lint) || defined(KERNEL))
+static const char rcsid[] =
+    "@(#) $Header: /usr/local/cvs/linux/tools/build/e100boot/libpcap-0.4/bpf/net/bpf_filter.c,v 1.1 1999/08/26 10:07:57 johana Exp $ (LBL)";
+#endif
+
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <net/bpf.h>
+
+#ifndef KERNEL
+#include <stdlib.h>
+#endif
+
+#define int32 bpf_int32
+#define u_int32 bpf_u_int32
+
+#ifndef LBL_ALIGN
+#if defined(sparc) || defined(mips) || defined(ibm032) || \
+    defined(__alpha) || defined(__hpux)
+#define LBL_ALIGN
+#endif
+#endif
+
+#ifndef LBL_ALIGN
+#include <netinet/in.h>
+
+#define EXTRACT_SHORT(p)       ((u_short)ntohs(*(u_short *)p))
+#define EXTRACT_LONG(p)                (ntohl(*(u_int32 *)p))
+#else
+#define EXTRACT_SHORT(p)\
+       ((u_short)\
+               ((u_short)*((u_char *)p+0)<<8|\
+                (u_short)*((u_char *)p+1)<<0))
+#define EXTRACT_LONG(p)\
+               ((u_int32)*((u_char *)p+0)<<24|\
+                (u_int32)*((u_char *)p+1)<<16|\
+                (u_int32)*((u_char *)p+2)<<8|\
+                (u_int32)*((u_char *)p+3)<<0)
+#endif
+
+#ifdef KERNEL
+#include <sys/mbuf.h>
+#define MINDEX(len, m, k) \
+{ \
+       len = m->m_len; \
+       while (k >= len) { \
+               k -= len; \
+               m = m->m_next; \
+               if (m == 0) \
+                       return 0; \
+               len = m->m_len; \
+       } \
+}
+
+static int
+m_xword(m, k, err)
+       register struct mbuf *m;
+       register int k, *err;
+{
+       register int len;
+       register u_char *cp, *np;
+       register struct mbuf *m0;
+
+       MINDEX(len, m, k);
+       cp = mtod(m, u_char *) + k;
+       if (len - k >= 4) {
+               *err = 0;
+               return EXTRACT_LONG(cp);
+       }
+       m0 = m->m_next;
+       if (m0 == 0 || m0->m_len + len - k < 4)
+               goto bad;
+       *err = 0;
+       np = mtod(m0, u_char *);
+       switch (len - k) {
+
+       case 1:
+               return (cp[0] << 24) | (np[0] << 16) | (np[1] << 8) | np[2];
+
+       case 2:
+               return (cp[0] << 24) | (cp[1] << 16) | (np[0] << 8) | np[1];
+
+       default:
+               return (cp[0] << 24) | (cp[1] << 16) | (cp[2] << 8) | np[0];
+       }
+    bad:
+       *err = 1;
+       return 0;
+}
+
+static int
+m_xhalf(m, k, err)
+       register struct mbuf *m;
+       register int k, *err;
+{
+       register int len;
+       register u_char *cp;
+       register struct mbuf *m0;
+
+       MINDEX(len, m, k);
+       cp = mtod(m, u_char *) + k;
+       if (len - k >= 2) {
+               *err = 0;
+               return EXTRACT_SHORT(cp);
+       }
+       m0 = m->m_next;
+       if (m0 == 0)
+               goto bad;
+       *err = 0;
+       return (cp[0] << 8) | mtod(m0, u_char *)[0];
+ bad:
+       *err = 1;
+       return 0;
+}
+#endif
+
+/*
+ * Execute the filter program starting at pc on the packet p
+ * wirelen is the length of the original packet
+ * buflen is the amount of data present
+ */
+u_int
+bpf_filter(pc, p, wirelen, buflen)
+       register struct bpf_insn *pc;
+       register u_char *p;
+       u_int wirelen;
+       register u_int buflen;
+{
+       register u_int32 A, X;
+       register int k;
+       int32 mem[BPF_MEMWORDS];
+
+       if (pc == 0)
+               /*
+                * No filter means accept all.
+                */
+               return (u_int)-1;
+       A = 0;
+       X = 0;
+       --pc;
+       while (1) {
+               ++pc;
+               switch (pc->code) {
+
+               default:
+#ifdef KERNEL
+                       return 0;
+#else
+                       abort();
+#endif                 
+               case BPF_RET|BPF_K:
+                       return (u_int)pc->k;
+
+               case BPF_RET|BPF_A:
+                       return (u_int)A;
+
+               case BPF_LD|BPF_W|BPF_ABS:
+                       k = pc->k;
+                       if (k + sizeof(int32) > buflen) {
+#ifdef KERNEL
+                               int merr;
+
+                               if (buflen != 0)
+                                       return 0;
+                               A = m_xword((struct mbuf *)p, k, &merr);
+                               if (merr != 0)
+                                       return 0;
+                               continue;
+#else
+                               return 0;
+#endif
+                       }
+                       A = EXTRACT_LONG(&p[k]);
+                       continue;
+
+               case BPF_LD|BPF_H|BPF_ABS:
+                       k = pc->k;
+                       if (k + sizeof(short) > buflen) {
+#ifdef KERNEL
+                               int merr;
+
+                               if (buflen != 0)
+                                       return 0;
+                               A = m_xhalf((struct mbuf *)p, k, &merr);
+                               continue;
+#else
+                               return 0;
+#endif
+                       }
+                       A = EXTRACT_SHORT(&p[k]);
+                       continue;
+
+               case BPF_LD|BPF_B|BPF_ABS:
+                       k = pc->k;
+                       if (k >= buflen) {
+#ifdef KERNEL
+                               register struct mbuf *m;
+                               register int len;
+
+                               if (buflen != 0)
+                                       return 0;
+                               m = (struct mbuf *)p;
+                               MINDEX(len, m, k);
+                               A = mtod(m, u_char *)[k];
+                               continue;
+#else
+                               return 0;
+#endif
+                       }
+                       A = p[k];
+                       continue;
+
+               case BPF_LD|BPF_W|BPF_LEN:
+                       A = wirelen;
+                       continue;
+
+               case BPF_LDX|BPF_W|BPF_LEN:
+                       X = wirelen;
+                       continue;
+
+               case BPF_LD|BPF_W|BPF_IND:
+                       k = X + pc->k;
+                       if (k + sizeof(int32) > buflen) {
+#ifdef KERNEL
+                               int merr;
+
+                               if (buflen != 0)
+                                       return 0;
+                               A = m_xword((struct mbuf *)p, k, &merr);
+                               if (merr != 0)
+                                       return 0;
+                               continue;
+#else
+                               return 0;
+#endif
+                       }
+                       A = EXTRACT_LONG(&p[k]);
+                       continue;
+
+               case BPF_LD|BPF_H|BPF_IND:
+                       k = X + pc->k;
+                       if (k + sizeof(short) > buflen) {
+#ifdef KERNEL
+                               int merr;
+
+                               if (buflen != 0)
+                                       return 0;
+                               A = m_xhalf((struct mbuf *)p, k, &merr);
+                               if (merr != 0)
+                                       return 0;
+                               continue;
+#else
+                               return 0;
+#endif
+                       }
+                       A = EXTRACT_SHORT(&p[k]);
+                       continue;
+
+               case BPF_LD|BPF_B|BPF_IND:
+                       k = X + pc->k;
+                       if (k >= buflen) {
+#ifdef KERNEL
+                               register struct mbuf *m;
+                               register int len;
+
+                               if (buflen != 0)
+                                       return 0;
+                               m = (struct mbuf *)p;
+                               MINDEX(len, m, k);
+                               A = mtod(m, u_char *)[k];
+                               continue;
+#else
+                               return 0;
+#endif
+                       }
+                       A = p[k];
+                       continue;
+
+               case BPF_LDX|BPF_MSH|BPF_B:
+                       k = pc->k;
+                       if (k >= buflen) {
+#ifdef KERNEL
+                               register struct mbuf *m;
+                               register int len;
+
+                               if (buflen != 0)
+                                       return 0;
+                               m = (struct mbuf *)p;
+                               MINDEX(len, m, k);
+                               X = (mtod(m, char *)[k] & 0xf) << 2;
+                               continue;
+#else
+                               return 0;
+#endif
+                       }
+                       X = (p[pc->k] & 0xf) << 2;
+                       continue;
+
+               case BPF_LD|BPF_IMM:
+                       A = pc->k;
+                       continue;
+
+               case BPF_LDX|BPF_IMM:
+                       X = pc->k;
+                       continue;
+
+               case BPF_LD|BPF_MEM:
+                       A = mem[pc->k];
+                       continue;
+                       
+               case BPF_LDX|BPF_MEM:
+                       X = mem[pc->k];
+                       continue;
+
+               case BPF_ST:
+                       mem[pc->k] = A;
+                       continue;
+
+               case BPF_STX:
+                       mem[pc->k] = X;
+                       continue;
+
+               case BPF_JMP|BPF_JA:
+                       pc += pc->k;
+                       continue;
+
+               case BPF_JMP|BPF_JGT|BPF_K:
+                       pc += (A > pc->k) ? pc->jt : pc->jf;
+                       continue;
+
+               case BPF_JMP|BPF_JGE|BPF_K:
+                       pc += (A >= pc->k) ? pc->jt : pc->jf;
+                       continue;
+
+               case BPF_JMP|BPF_JEQ|BPF_K:
+                       pc += (A == pc->k) ? pc->jt : pc->jf;
+                       continue;
+
+               case BPF_JMP|BPF_JSET|BPF_K:
+                       pc += (A & pc->k) ? pc->jt : pc->jf;
+                       continue;
+
+               case BPF_JMP|BPF_JGT|BPF_X:
+                       pc += (A > X) ? pc->jt : pc->jf;
+                       continue;
+
+               case BPF_JMP|BPF_JGE|BPF_X:
+                       pc += (A >= X) ? pc->jt : pc->jf;
+                       continue;
+
+               case BPF_JMP|BPF_JEQ|BPF_X:
+                       pc += (A == X) ? pc->jt : pc->jf;
+                       continue;
+
+               case BPF_JMP|BPF_JSET|BPF_X:
+                       pc += (A & X) ? pc->jt : pc->jf;
+                       continue;
+
+               case BPF_ALU|BPF_ADD|BPF_X:
+                       A += X;
+                       continue;
+                       
+               case BPF_ALU|BPF_SUB|BPF_X:
+                       A -= X;
+                       continue;
+                       
+               case BPF_ALU|BPF_MUL|BPF_X:
+                       A *= X;
+                       continue;
+                       
+               case BPF_ALU|BPF_DIV|BPF_X:
+                       if (X == 0)
+                               return 0;
+                       A /= X;
+                       continue;
+                       
+               case BPF_ALU|BPF_AND|BPF_X:
+                       A &= X;
+                       continue;
+                       
+               case BPF_ALU|BPF_OR|BPF_X:
+                       A |= X;
+                       continue;
+
+               case BPF_ALU|BPF_LSH|BPF_X:
+                       A <<= X;
+                       continue;
+
+               case BPF_ALU|BPF_RSH|BPF_X:
+                       A >>= X;
+                       continue;
+
+               case BPF_ALU|BPF_ADD|BPF_K:
+                       A += pc->k;
+                       continue;
+                       
+               case BPF_ALU|BPF_SUB|BPF_K:
+                       A -= pc->k;
+                       continue;
+                       
+               case BPF_ALU|BPF_MUL|BPF_K:
+                       A *= pc->k;
+                       continue;
+                       
+               case BPF_ALU|BPF_DIV|BPF_K:
+                       A /= pc->k;
+                       continue;
+                       
+               case BPF_ALU|BPF_AND|BPF_K:
+                       A &= pc->k;
+                       continue;
+                       
+               case BPF_ALU|BPF_OR|BPF_K:
+                       A |= pc->k;
+                       continue;
+
+               case BPF_ALU|BPF_LSH|BPF_K:
+                       A <<= pc->k;
+                       continue;
+
+               case BPF_ALU|BPF_RSH|BPF_K:
+                       A >>= pc->k;
+                       continue;
+
+               case BPF_ALU|BPF_NEG:
+                       A = -A;
+                       continue;
+
+               case BPF_MISC|BPF_TAX:
+                       X = A;
+                       continue;
+
+               case BPF_MISC|BPF_TXA:
+                       A = X;
+                       continue;
+               }
+       }
+}
+
+#ifdef KERNEL
+/*
+ * Return true if the 'fcode' is a valid filter program.
+ * The constraints are that each jump be forward and to a valid
+ * code.  The code must terminate with either an accept or reject. 
+ * 'valid' is an array for use by the routine (it must be at least
+ * 'len' bytes long).  
+ *
+ * The kernel needs to be able to verify an application's filter code.
+ * Otherwise, a bogus program could easily crash the system.
+ */
+int
+bpf_validate(f, len)
+       struct bpf_insn *f;
+       int len;
+{
+       register int i;
+       register struct bpf_insn *p;
+
+       for (i = 0; i < len; ++i) {
+               /*
+                * Check that that jumps are forward, and within 
+                * the code block.
+                */
+               p = &f[i];
+               if (BPF_CLASS(p->code) == BPF_JMP) {
+                       register int from = i + 1;
+
+                       if (BPF_OP(p->code) == BPF_JA) {
+                               if (from + p->k >= (unsigned)len)
+                                       return 0;
+                       }
+                       else if (from + p->jt >= len || from + p->jf >= len)
+                               return 0;
+               }
+               /*
+                * Check that memory operations use valid addresses.
+                */
+               if ((BPF_CLASS(p->code) == BPF_ST ||
+                    (BPF_CLASS(p->code) == BPF_LD && 
+                     (p->code & 0xe0) == BPF_MEM)) &&
+                   (p->k >= BPF_MEMWORDS || p->k < 0))
+                       return 0;
+               /*
+                * Check for constant division by 0.
+                */
+               if (p->code == (BPF_ALU|BPF_DIV|BPF_K) && p->k == 0)
+                       return 0;
+       }
+       return BPF_CLASS(f[len - 1].code) == BPF_RET;
+}
+#endif