Move bpf/net/bpf-filter.c to toplevel directory - it's the sole file in bpf/...

Fix autotools .devel failure in OOT-build while at it

1 files changed, 539 insertions, 0 deletions

diff --git a/bpf_filter.c b/bpf_filter.c
new file mode 100644
index 00000000..1484e08b
--- /dev/null
+++ b/bpf_filter.c
@@ -0,0 +1,539 @@
+/*-
+ * 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
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <pcap/pcap-inttypes.h>
+#include "pcap-types.h"
+
+#ifndef _WIN32
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#endif /* _WIN32 */
+
+#include <pcap/bpf.h>
+
+#include <stdlib.h>
+
+#define int32 bpf_int32
+#define u_int32 bpf_u_int32
+
+#ifndef LBL_ALIGN
+/*
+ * XXX - IA-64?  If not, this probably won't work on Win64 IA-64
+ * systems, unless LBL_ALIGN is defined elsewhere for them.
+ * XXX - SuperH?  If not, this probably won't work on WinCE SuperH
+ * systems, unless LBL_ALIGN is defined elsewhere for them.
+ */
+#if defined(sparc) || defined(__sparc__) || defined(mips) || \
+    defined(ibm032) || defined(__alpha) || defined(__hpux) || \
+    defined(__arm__)
+#define LBL_ALIGN
+#endif
+#endif
+
+#ifndef LBL_ALIGN
+#ifndef _WIN32
+#include <netinet/in.h>
+#endif
+
+#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 __linux__
+#include <linux/types.h>
+#include <linux/if_packet.h>
+#include <linux/filter.h>
+#endif
+
+enum {
+        BPF_S_ANC_NONE,
+        BPF_S_ANC_VLAN_TAG,
+        BPF_S_ANC_VLAN_TAG_PRESENT,
+};
+
+/*
+ * 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
+ * aux_data is auxiliary data, currently used only when interpreting
+ * filters intended for the Linux kernel in cases where the kernel
+ * rejects the filter; it contains VLAN tag information
+ * For the kernel, p is assumed to be a pointer to an mbuf if buflen is 0,
+ * in all other cases, p is a pointer to a buffer and buflen is its size.
+ *
+ * Thanks to Ani Sinha <ani@arista.com> for providing initial implementation
+ */
+u_int
+bpf_filter_with_aux_data(const struct bpf_insn *pc, const u_char *p,
+    u_int wirelen, u_int buflen, const struct bpf_aux_data *aux_data)
+{
+	register u_int32 A, X;
+	register bpf_u_int32 k;
+	u_int32 mem[BPF_MEMWORDS];
+
+	if (pc == 0)
+		/*
+		 * No filter means accept all.
+		 */
+		return (u_int)-1;
+	A = 0;
+	X = 0;
+	--pc;
+	for (;;) {
+		++pc;
+		switch (pc->code) {
+
+		default:
+			abort();
+		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 > buflen || sizeof(int32_t) > buflen - k) {
+				return 0;
+			}
+			A = EXTRACT_LONG(&p[k]);
+			continue;
+
+		case BPF_LD|BPF_H|BPF_ABS:
+			k = pc->k;
+			if (k > buflen || sizeof(int16_t) > buflen - k) {
+				return 0;
+			}
+			A = EXTRACT_SHORT(&p[k]);
+			continue;
+
+		case BPF_LD|BPF_B|BPF_ABS:
+			switch (pc->k) {
+
+#if defined(SKF_AD_VLAN_TAG) && defined(SKF_AD_VLAN_TAG_PRESENT)
+			case SKF_AD_OFF + SKF_AD_VLAN_TAG:
+				if (!aux_data)
+					return 0;
+				A = aux_data->vlan_tag;
+				break;
+
+			case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
+				if (!aux_data)
+					return 0;
+				A = aux_data->vlan_tag_present;
+				break;
+#endif
+			default:
+				k = pc->k;
+				if (k >= buflen) {
+					return 0;
+				}
+				A = p[k];
+				break;
+			}
+			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 (pc->k > buflen || X > buflen - pc->k ||
+			    sizeof(int32_t) > buflen - k) {
+				return 0;
+			}
+			A = EXTRACT_LONG(&p[k]);
+			continue;
+
+		case BPF_LD|BPF_H|BPF_IND:
+			k = X + pc->k;
+			if (X > buflen || pc->k > buflen - X ||
+			    sizeof(int16_t) > buflen - k) {
+				return 0;
+			}
+			A = EXTRACT_SHORT(&p[k]);
+			continue;
+
+		case BPF_LD|BPF_B|BPF_IND:
+			k = X + pc->k;
+			if (pc->k >= buflen || X >= buflen - pc->k) {
+				return 0;
+			}
+			A = p[k];
+			continue;
+
+		case BPF_LDX|BPF_MSH|BPF_B:
+			k = pc->k;
+			if (k >= buflen) {
+				return 0;
+			}
+			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:
+			/*
+			 * XXX - we currently implement "ip6 protochain"
+			 * with backward jumps, so sign-extend pc->k.
+			 */
+			pc += (bpf_int32)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_MOD|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_XOR|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_MOD|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_XOR|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:
+			/*
+			 * Most BPF arithmetic is unsigned, but negation
+			 * can't be unsigned; throw some casts to
+			 * specify what we're trying to do.
+			 */
+			A = (u_int32)(-(int32)A);
+			continue;
+
+		case BPF_MISC|BPF_TAX:
+			X = A;
+			continue;
+
+		case BPF_MISC|BPF_TXA:
+			A = X;
+			continue;
+		}
+	}
+}
+
+u_int
+bpf_filter(const struct bpf_insn *pc, const u_char *p, u_int wirelen,
+    u_int buflen)
+{
+	return bpf_filter_with_aux_data(pc, p, wirelen, buflen, NULL);
+}
+
+
+/*
+ * Return true if the 'fcode' is a valid filter program.
+ * The constraints are that each jump be forward and to a valid
+ * code, that memory accesses are within valid ranges (to the
+ * extent that this can be checked statically; loads of packet
+ * data have to be, and are, also checked at run time), and that
+ * the code terminates with either an accept or reject.
+ *
+ * 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(const struct bpf_insn *f, int len)
+{
+	u_int i, from;
+	const struct bpf_insn *p;
+
+	if (len < 1)
+		return 0;
+
+	for (i = 0; i < (u_int)len; ++i) {
+		p = &f[i];
+		switch (BPF_CLASS(p->code)) {
+		/*
+		 * Check that memory operations use valid addresses.
+		 */
+		case BPF_LD:
+		case BPF_LDX:
+			switch (BPF_MODE(p->code)) {
+			case BPF_IMM:
+				break;
+			case BPF_ABS:
+			case BPF_IND:
+			case BPF_MSH:
+				/*
+				 * There's no maximum packet data size
+				 * in userland.  The runtime packet length
+				 * check suffices.
+				 */
+				break;
+			case BPF_MEM:
+				if (p->k >= BPF_MEMWORDS)
+					return 0;
+				break;
+			case BPF_LEN:
+				break;
+			default:
+				return 0;
+			}
+			break;
+		case BPF_ST:
+		case BPF_STX:
+			if (p->k >= BPF_MEMWORDS)
+				return 0;
+			break;
+		case BPF_ALU:
+			switch (BPF_OP(p->code)) {
+			case BPF_ADD:
+			case BPF_SUB:
+			case BPF_MUL:
+			case BPF_OR:
+			case BPF_AND:
+			case BPF_XOR:
+			case BPF_LSH:
+			case BPF_RSH:
+			case BPF_NEG:
+				break;
+			case BPF_DIV:
+			case BPF_MOD:
+				/*
+				 * Check for constant division or modulus
+				 * by 0.
+				 */
+				if (BPF_SRC(p->code) == BPF_K && p->k == 0)
+					return 0;
+				break;
+			default:
+				return 0;
+			}
+			break;
+		case BPF_JMP:
+			/*
+			 * Check that jumps are within the code block,
+			 * and that unconditional branches don't go
+			 * backwards as a result of an overflow.
+			 * Unconditional branches have a 32-bit offset,
+			 * so they could overflow; we check to make
+			 * sure they don't.  Conditional branches have
+			 * an 8-bit offset, and the from address is <=
+			 * BPF_MAXINSNS, and we assume that BPF_MAXINSNS
+			 * is sufficiently small that adding 255 to it
+			 * won't overflow.
+			 *
+			 * We know that len is <= BPF_MAXINSNS, and we
+			 * assume that BPF_MAXINSNS is < the maximum size
+			 * of a u_int, so that i + 1 doesn't overflow.
+			 *
+			 * For userland, we don't know that the from
+			 * or len are <= BPF_MAXINSNS, but we know that
+			 * from <= len, and, except on a 64-bit system,
+			 * it's unlikely that len, if it truly reflects
+			 * the size of the program we've been handed,
+			 * will be anywhere near the maximum size of
+			 * a u_int.  We also don't check for backward
+			 * branches, as we currently support them in
+			 * userland for the protochain operation.
+			 */
+			from = i + 1;
+			switch (BPF_OP(p->code)) {
+			case BPF_JA:
+				if (from + p->k >= (u_int)len)
+					return 0;
+				break;
+			case BPF_JEQ:
+			case BPF_JGT:
+			case BPF_JGE:
+			case BPF_JSET:
+				if (from + p->jt >= (u_int)len || from + p->jf >= (u_int)len)
+					return 0;
+				break;
+			default:
+				return 0;
+			}
+			break;
+		case BPF_RET:
+			break;
+		case BPF_MISC:
+			break;
+		default:
+			return 0;
+		}
+	}
+	return BPF_CLASS(f[len - 1].code) == BPF_RET;
+}