/*
 * Copyright (c) 1999 - 2006 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden).
 * All rights reserved.
 *
 * Portions Copyright (c) 2009 Apple Inc. 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.
 *
 * 3. Neither the name of the Institute 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 INSTITUTE 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 INSTITUTE 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.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif
#include <stdio.h>
#include <string.h>
#include <err.h>
#include <roken.h>

#include "asn1-common.h"
#include "check-common.h"

RCSID("$Id$");

struct map_page {
    void *start;
    size_t size;
    void *data_start;
    size_t data_size;
    enum map_type type;
};

/* #undef HAVE_MMAP */

void *
map_alloc(enum map_type type, const void *buf,
          size_t size, struct map_page **map)
{
#ifndef HAVE_MMAP
    unsigned char *p;
    size_t len = size + sizeof(long) * 2;
    int i;

    *map = ecalloc(1, sizeof(**map));

    p = emalloc(len);
    (*map)->type = type;
    (*map)->start = p;
    (*map)->size = len;
    (*map)->data_start = p + sizeof(long);
    for (i = sizeof(long); i > 0; i--)
        p[sizeof(long) - i] = 0xff - i;
    for (i = sizeof(long); i > 0; i--)
        p[len - i] = 0xff - i;
#else
    unsigned char *p;
    int flags, ret, fd;
    size_t pagesize = getpagesize();

    *map = ecalloc(1, sizeof(**map));

    (*map)->type = type;

#ifdef MAP_ANON
    flags = MAP_ANON;
    fd = -1;
#else
    flags = 0;
    fd = open ("/dev/zero", O_RDONLY);
    if(fd < 0)
        err (1, "open /dev/zero");
#endif
    flags |= MAP_PRIVATE;

    (*map)->size = size + pagesize - (size % pagesize) + pagesize * 2;

    p = (unsigned char *)mmap(0, (*map)->size, PROT_READ | PROT_WRITE,
                              flags, fd, 0);
    if (p == (unsigned char *)MAP_FAILED)
        err (1, "mmap");

    (*map)->start = p;

    ret = mprotect (p, pagesize, 0);
    if (ret < 0)
        err (1, "mprotect");

    ret = mprotect (p + (*map)->size - pagesize, pagesize, 0);
    if (ret < 0)
        err (1, "mprotect");

    switch (type) {
    case OVERRUN:
        (*map)->data_start = p + (*map)->size - pagesize - size;
        break;
    case UNDERRUN:
        (*map)->data_start = p + pagesize;
        break;
   default:
        abort();
    }
#endif
    (*map)->data_size = size;
    if (buf)
        memcpy((*map)->data_start, buf, size);
    return (*map)->data_start;
}

void
map_free(struct map_page *map, const char *test_name, const char *map_name)
{
#ifndef HAVE_MMAP
    unsigned char *p = map->start;
    int i;

    for (i = sizeof(long); i > 0; i--)
        if (p[sizeof(long) - i] != 0xff - i)
            errx(1, "%s: %s underrun %d\n", test_name, map_name, i);
    for (i = sizeof(long); i > 0; i--)
        if (p[map->size - i] != 0xff - i)
            errx(1, "%s: %s overrun %lu\n", test_name, map_name,
                 (unsigned long)map->size - i);
    free(map->start);
#else
    int ret;

    ret = munmap (map->start, map->size);
    if (ret < 0)
        err (1, "munmap");
#endif
    free(map);
}

static void
print_bytes (unsigned const char *buf, size_t len)
{
    int i;

    for (i = 0; i < len; ++i)
        printf ("%02x ", buf[i]);
}

#ifndef MAP_FAILED
#define MAP_FAILED (-1)
#endif

static char *current_test = "<uninit>";
static char *current_state = "<uninit>";

static RETSIGTYPE
segv_handler(int sig)
{
    int fd;
    char msg[] = "SIGSEGV i current test: ";

    fd = open("/dev/stdout", O_WRONLY, 0600);
    if (fd >= 0) {
        write(fd, msg, sizeof(msg));
        write(fd, current_test, strlen(current_test));
        write(fd, " ", 1);
        write(fd, current_state, strlen(current_state));
        write(fd, "\n", 1);
        close(fd);
    }
    _exit(1);
}

int
generic_test (const struct test_case *tests,
              unsigned ntests,
              size_t data_size,
              int (ASN1CALL *encode)(unsigned char *, size_t, void *, size_t *),
              int (ASN1CALL *length)(void *),
              int (ASN1CALL *decode)(unsigned char *, size_t, void *, size_t *),
              int (ASN1CALL *free_data)(void *),
              int (*cmp)(void *a, void *b),
              int (ASN1CALL *copy)(const void *from, void *to))
{
    unsigned char *buf, *buf2;
    int i;
    int failures = 0;
    void *data;
    struct map_page *data_map, *buf_map, *buf2_map;

#ifdef HAVE_SIGACTION
    struct sigaction sa, osa;
#endif

    for (i = 0; i < ntests; ++i) {
        int ret;
        size_t sz, consumed_sz, length_sz, buf_sz;
        void *to = NULL;

        current_test = tests[i].name;

        current_state = "init";

#ifdef HAVE_SIGACTION
        sigemptyset (&sa.sa_mask);
        sa.sa_flags = 0;
#ifdef SA_RESETHAND
        sa.sa_flags |= SA_RESETHAND;
#endif
        sa.sa_handler = segv_handler;
        sigaction (SIGSEGV, &sa, &osa);
#endif

        data = map_alloc(OVERRUN, NULL, data_size, &data_map);

        buf_sz = tests[i].byte_len;
        buf = map_alloc(UNDERRUN, NULL, buf_sz, &buf_map);

        current_state = "encode";
        ret = (*encode) (buf + buf_sz - 1, buf_sz,
                         tests[i].val, &sz);
        if (ret != 0) {
            printf ("encoding of %s failed %d\n", tests[i].name, ret);
            ++failures;
            continue;
        }
        if (sz != tests[i].byte_len) {
            printf ("encoding of %s has wrong len (%lu != %lu)\n",
                    tests[i].name,
                    (unsigned long)sz, (unsigned long)tests[i].byte_len);
            ++failures;
            continue;
        }

        current_state = "length";
        length_sz = (*length) (tests[i].val);
        if (sz != length_sz) {
            printf ("length for %s is bad (%lu != %lu)\n",
                    tests[i].name, (unsigned long)length_sz, (unsigned long)sz);
            ++failures;
            continue;
        }

        current_state = "memcmp";
        if (memcmp (buf, tests[i].bytes, tests[i].byte_len) != 0) {
            printf ("encoding of %s has bad bytes:\n"
                    "correct: ", tests[i].name);
            print_bytes ((unsigned char *)tests[i].bytes, tests[i].byte_len);
            printf ("\nactual:  ");
            print_bytes (buf, sz);
            printf ("\n");
#if 0
            rk_dumpdata("correct", tests[i].bytes, tests[i].byte_len);
            rk_dumpdata("actual", buf, sz);
            exit (1);
#endif
            ++failures;
            continue;
        }

        buf2 = map_alloc(OVERRUN, buf, sz, &buf2_map);

        current_state = "decode";
        ret = (*decode) (buf2, sz, data, &consumed_sz);
        if (ret != 0) {
            printf ("decoding of %s failed %d\n", tests[i].name, ret);
            ++failures;
            continue;
        }
        if (sz != consumed_sz) {
            printf ("different length decoding %s (%ld != %ld)\n",
                    tests[i].name,
                    (unsigned long)sz, (unsigned long)consumed_sz);
            ++failures;
            continue;
        }
        current_state = "cmp";
        if ((*cmp)(data, tests[i].val) != 0) {
            printf ("%s: comparison failed\n", tests[i].name);
            ++failures;
            continue;
        }

        current_state = "copy";
        if (copy) {
            to = emalloc(data_size);
            ret = (*copy)(data, to);
            if (ret != 0) {
                printf ("copy of %s failed %d\n", tests[i].name, ret);
                ++failures;
                continue;
            }

            current_state = "cmp-copy";
            if ((*cmp)(data, to) != 0) {
                printf ("%s: copy comparison failed\n", tests[i].name);
                ++failures;
                continue;
            }
        }

        current_state = "free";
        if (free_data) {
            (*free_data)(data);
            if (to) {
                (*free_data)(to);
                free(to);
            }
        }

        current_state = "free";
        map_free(buf_map, tests[i].name, "encode");
        map_free(buf2_map, tests[i].name, "decode");
        map_free(data_map, tests[i].name, "data");

#ifdef HAVE_SIGACTION
        sigaction (SIGSEGV, &osa, NULL);
#endif
    }
    current_state = "done";
    return failures;
}

/*
 * check for failures
 *
 * a test size (byte_len) of -1 means that the test tries to trigger a
 * integer overflow (and later a malloc of to little memory), just
 * allocate some memory and hope that is enough for that test.
 */

int
generic_decode_fail (const struct test_case *tests,
                     unsigned ntests,
                     size_t data_size,
                     int (ASN1CALL *decode)(unsigned char *, size_t, void *, size_t *))
{
    unsigned char *buf;
    int i;
    int failures = 0;
    void *data;
    struct map_page *data_map, *buf_map;

#ifdef HAVE_SIGACTION
    struct sigaction sa, osa;
#endif

    for (i = 0; i < ntests; ++i) {
        int ret;
        size_t sz;
        const void *bytes;

        current_test = tests[i].name;

        current_state = "init";

#ifdef HAVE_SIGACTION
        sigemptyset (&sa.sa_mask);
        sa.sa_flags = 0;
#ifdef SA_RESETHAND
        sa.sa_flags |= SA_RESETHAND;
#endif
        sa.sa_handler = segv_handler;
        sigaction (SIGSEGV, &sa, &osa);
#endif

        data = map_alloc(OVERRUN, NULL, data_size, &data_map);

        if (tests[i].byte_len < 0xffffff && tests[i].byte_len >= 0) {
            sz = tests[i].byte_len;
            bytes = tests[i].bytes;
        } else {
            sz = 4096;
            bytes = NULL;
        }

        buf = map_alloc(OVERRUN, bytes, sz, &buf_map);

        if (tests[i].byte_len == -1)
            memset(buf, 0, sz);

        current_state = "decode";
        ret = (*decode) (buf, tests[i].byte_len, data, &sz);
        if (ret == 0) {
            printf ("sucessfully decoded %s\n", tests[i].name);
            ++failures;
            continue;
        }

        current_state = "free";
        if (buf)
            map_free(buf_map, tests[i].name, "encode");
        map_free(data_map, tests[i].name, "data");

#ifdef HAVE_SIGACTION
        sigaction (SIGSEGV, &osa, NULL);
#endif
    }
    current_state = "done";
    return failures;
}