/*-
 * Copyright (C) 2008-2009 Jung-uk Kim <jkim@FreeBSD.org>. All rights reserved.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY AUTHOR 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 AUTHOR 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.
 */

#include <sys/cdefs.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>

#include <sys/types.h>

#include <net/bpf.h>

#include BPF_TEST_H

#define PASSED          0
#define FAILED          1
#define FATAL           -1

#ifndef LOG_LEVEL
#define LOG_LEVEL       1
#endif

#ifdef BPF_BENCHMARK
#define BPF_NRUNS       10000000
#else
#define BPF_NRUNS       1
#endif

static void     sig_handler(int);

static int      nins = sizeof(pc) / sizeof(pc[0]);
static int      verbose = LOG_LEVEL;

#ifdef BPF_JIT_COMPILER

#include <libutil.h>

#include <net/bpf_jitter.h>

static u_int
bpf_compile_and_filter(void)
{
        bpf_jit_filter  *filter;
        u_int           i, ret;

        /* Compile the BPF filter program and generate native code. */
        if ((filter = bpf_jitter(pc, nins)) == NULL) {
                if (verbose > 1)
                        printf("Failed to allocate memory:\t");
                if (verbose > 0)
                        printf("FATAL\n");
                exit(FATAL);
        }
        if (verbose > 2) {
                printf("\n");
                hexdump(filter->func, filter->size, NULL, HD_OMIT_CHARS);
        }

        for (i = 0; i < BPF_NRUNS; i++)
                ret = (*(filter->func))(pkt, wirelen, buflen);

        bpf_destroy_jit_filter(filter);

        return (ret);
}

#else

u_int   bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);

#endif

#ifdef BPF_VALIDATE
static const u_short    bpf_code_map[] = {
        0x10ff, /* 0x00-0x0f: 1111111100001000 */
        0x3070, /* 0x10-0x1f: 0000111000001100 */
        0x3131, /* 0x20-0x2f: 1000110010001100 */
        0x3031, /* 0x30-0x3f: 1000110000001100 */
        0x3131, /* 0x40-0x4f: 1000110010001100 */
        0x1011, /* 0x50-0x5f: 1000100000001000 */
        0x1013, /* 0x60-0x6f: 1100100000001000 */
        0x1010, /* 0x70-0x7f: 0000100000001000 */
        0x0093, /* 0x80-0x8f: 1100100100000000 */
        0x1010, /* 0x90-0x9f: 0000100000001000 */
        0x1010, /* 0xa0-0xaf: 0000100000001000 */
        0x0002, /* 0xb0-0xbf: 0100000000000000 */
        0x0000, /* 0xc0-0xcf: 0000000000000000 */
        0x0000, /* 0xd0-0xdf: 0000000000000000 */
        0x0000, /* 0xe0-0xef: 0000000000000000 */
        0x0000  /* 0xf0-0xff: 0000000000000000 */
};

#define BPF_VALIDATE_CODE(c)    \
    ((c) <= 0xff && (bpf_code_map[(c) >> 4] & (1 << ((c) & 0xf))) != 0)

/*
 * XXX Copied from sys/net/bpf_filter.c and modified.
 *
 * 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.
 *
 * The kernel needs to be able to verify an application's filter code.
 * Otherwise, a bogus program could easily crash the system.
 */
static int
bpf_validate(const struct bpf_insn *f, int len)
{
        register int i;
        register const struct bpf_insn *p;

        /* Do not accept negative length filter. */
        if (len < 0)
                return (0);

        /* An empty filter means accept all. */
        if (len == 0)
                return (1);

        for (i = 0; i < len; ++i) {
                p = &f[i];
                /*
                 * Check that the code is valid.
                 */
                if (!BPF_VALIDATE_CODE(p->code))
                        return (0);
                /*
                 * Check that jumps are forward, and within
                 * the code block.
                 */
                if (BPF_CLASS(p->code) == BPF_JMP) {
                        register u_int offset;

                        if (p->code == (BPF_JMP|BPF_JA))
                                offset = p->k;
                        else
                                offset = p->jt > p->jf ? p->jt : p->jf;
                        if (offset >= (u_int)(len - i) - 1)
                                return (0);
                        continue;
                }
                /*
                 * Check that memory operations use valid addresses.
                 */
                if (p->code == BPF_ST || p->code == BPF_STX ||
                    p->code == (BPF_LD|BPF_MEM) ||
                    p->code == (BPF_LDX|BPF_MEM)) {
                        if (p->k >= BPF_MEMWORDS)
                                return (0);
                        continue;
                }
                /*
                 * Check for constant division by 0.
                 */
                if ((p->code == (BPF_ALU|BPF_DIV|BPF_K) ||
                    p->code == (BPF_ALU|BPF_MOD|BPF_K)) && p->k == 0)
                        return (0);
        }
        return (BPF_CLASS(f[len - 1].code) == BPF_RET);
}
#endif

int
main(void)
{
#ifndef BPF_JIT_COMPILER
        u_int   i;
#endif
        u_int   ret;
        int     sig;
#ifdef BPF_VALIDATE
        int     valid;
#endif

        /* Try to catch all signals */
        for (sig = SIGHUP; sig <= SIGUSR2; sig++)
                signal(sig, sig_handler);

#ifdef BPF_VALIDATE
        valid = bpf_validate(pc, nins);
        if (valid != 0 && invalid != 0) {
                if (verbose > 1)
                        printf("Validated invalid instruction(s):\t");
                if (verbose > 0)
                        printf("FAILED\n");
                return (FAILED);
        } else if (valid == 0 && invalid == 0) {
                if (verbose > 1)
                        printf("Invalidated valid instruction(s):\t");
                if (verbose > 0)
                        printf("FAILED\n");
                return (FAILED);
        } else if (invalid != 0) {
                if (verbose > 1)
                        printf("Expected and invalidated:\t");
                if (verbose > 0)
                        printf("PASSED\n");
                return (PASSED);
        }
#endif

#ifdef BPF_JIT_COMPILER
        ret = bpf_compile_and_filter();
#else
        for (i = 0; i < BPF_NRUNS; i++)
                ret = bpf_filter(nins != 0 ? pc : NULL, pkt, wirelen, buflen);
#endif
        if (expect_signal != 0) {
                if (verbose > 1)
                        printf("Expected signal %d but got none:\t",
                            expect_signal);
                if (verbose > 0)
                        printf("FAILED\n");
                return (FAILED);
        }
        if (ret != expect) {
                if (verbose > 1)
                        printf("Expected 0x%x but got 0x%x:\t", expect, ret);
                if (verbose > 0)
                        printf("FAILED\n");
                return (FAILED);
        }
        if (verbose > 1)
                printf("Expected and got 0x%x:\t", ret);
        if (verbose > 0)
                printf("PASSED\n");

        return (PASSED);
}

static void
sig_handler(int sig)
{

        if (expect_signal == 0) {
                if (verbose > 1)
                        printf("Received unexpected signal %d:\t", sig);
                if (verbose > 0)
                        printf("FATAL\n");
                exit(FATAL);
        }
        if (expect_signal != sig) {
                if (verbose > 1)
                        printf("Expected signal %d but got %d:\t",
                            expect_signal, sig);
                if (verbose > 0)
                        printf("FAILED\n");
                exit(FAILED);
        }

        if (verbose > 1)
                printf("Expected and got signal %d:\t", sig);
        if (verbose > 0)
                printf("PASSED\n");

        exit(PASSED);
}