/* $OpenBSD: deflate.c,v 1.3 2001/08/20 02:45:22 hugh Exp $ */

/*-
 * Copyright (c) 2001 Jean-Jacques Bernard-Gundol (jj@wabbitt.org)
 *
 * 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. The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/*
 * This file contains a wrapper around the deflate algo compression
 * functions using the zlib library (see sys/contrib/zlib)
 */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/sdt.h>
#include <sys/systm.h>
#include <contrib/zlib/zlib.h>

#include <opencrypto/cryptodev.h>
#include <opencrypto/deflate.h>

SDT_PROVIDER_DECLARE(opencrypto);
SDT_PROBE_DEFINE2(opencrypto, deflate, deflate_global, entry,
    "int", "uint32_t");
SDT_PROBE_DEFINE6(opencrypto, deflate, deflate_global, bad,
    "int", "int", "int", "int", "int", "int");
SDT_PROBE_DEFINE6(opencrypto, deflate, deflate_global, iter,
    "int", "int", "int", "int", "int", "int");
SDT_PROBE_DEFINE2(opencrypto, deflate, deflate_global, return,
    "int", "uint32_t");

int window_inflate = -1 * MAX_WBITS;
int window_deflate = -12;

static void *
crypto_zalloc(void *nil, u_int type, u_int size)
{
        void *ptr;

        ptr = malloc(type *size, M_CRYPTO_DATA, M_NOWAIT);
        return ptr;
}

static void
crypto_zfree(void *nil, void *ptr)
{

        free(ptr, M_CRYPTO_DATA);
}

/*
 * This function takes a block of data and (de)compress it using the deflate
 * algorithm
 */

uint32_t
deflate_global(uint8_t *data, uint32_t size, int decomp, uint8_t **out)
{
        /* decomp indicates whether we compress (0) or decompress (1) */

        z_stream zbuf;
        uint8_t *output;
        uint32_t count, result;
        int error, i;
        struct deflate_buf *bufh, *bufp;

        SDT_PROBE2(opencrypto, deflate, deflate_global, entry, decomp, size);

        bufh = bufp = NULL;
        if (!decomp) {
                i = 1;
        } else {
                /*
                 * Choose a buffer with 4x the size of the input buffer
                 * for the size of the output buffer in the case of
                 * decompression. If it's not sufficient, it will need to be
                 * updated while the decompression is going on.
                 */
                i = 4;
        }
        /*
         * Make sure we do have enough output space.  Repeated calls to
         * deflate need at least 6 bytes of output buffer space to avoid
         * repeated markers.  We will always provide at least 16 bytes.
         */
        while ((size * i) < 16)
                i++;

        bufh = bufp = malloc(sizeof(*bufp) + (size_t)(size * i),
            M_CRYPTO_DATA, M_NOWAIT);
        if (bufp == NULL) {
                SDT_PROBE6(opencrypto, deflate, deflate_global, bad,
                    decomp, 0, __LINE__, 0, 0, 0);
                goto bad2;
        }
        bufp->next = NULL;
        bufp->size = size * i;

        bzero(&zbuf, sizeof(z_stream));
        zbuf.zalloc = crypto_zalloc;
        zbuf.zfree = crypto_zfree;
        zbuf.opaque = Z_NULL;
        zbuf.next_in = data;    /* Data that is going to be processed. */
        zbuf.avail_in = size;   /* Total length of data to be processed. */
        zbuf.next_out = bufp->data;
        zbuf.avail_out = bufp->size;

        error = decomp ? inflateInit2(&zbuf, window_inflate) :
            deflateInit2(&zbuf, Z_DEFAULT_COMPRESSION, Z_METHOD,
                    window_deflate, Z_MEMLEVEL, Z_DEFAULT_STRATEGY);
        if (error != Z_OK) {
                SDT_PROBE6(opencrypto, deflate, deflate_global, bad,
                    decomp, error, __LINE__, 0, 0, 0);
                goto bad;
        }

        for (;;) {
                error = decomp ? inflate(&zbuf, Z_SYNC_FLUSH) :
                                 deflate(&zbuf, Z_FINISH);
                if (error != Z_OK && error != Z_STREAM_END) {
                        SDT_PROBE6(opencrypto, deflate, deflate_global, bad,
                            decomp, error, __LINE__,
                            zbuf.avail_in, zbuf.avail_out, zbuf.total_out);
                        goto bad;
                }
                SDT_PROBE6(opencrypto, deflate, deflate_global, iter,
                    decomp, error, __LINE__,
                    zbuf.avail_in, zbuf.avail_out, zbuf.total_out);
                if (decomp && zbuf.avail_in == 0 && error == Z_STREAM_END) {
                        /* Done. */
                        break;
                } else if (!decomp && error == Z_STREAM_END) {
                        /* Done. */
                        break;
                } else if (zbuf.avail_out == 0) {
                        struct deflate_buf *p;

                        /* We need more output space for another iteration. */
                        p = malloc(sizeof(*p) + (size_t)(size * i),
                            M_CRYPTO_DATA, M_NOWAIT);
                        if (p == NULL) {
                                SDT_PROBE6(opencrypto, deflate, deflate_global,
                                    bad, decomp, 0, __LINE__, 0, 0, 0);
                                goto bad;
                        }
                        p->next = NULL;
                        p->size = size * i;
                        bufp->next = p;
                        bufp = p;
                        zbuf.next_out = bufp->data;
                        zbuf.avail_out = bufp->size;
                } else {
                        /* Unexpect result. */
                        SDT_PROBE6(opencrypto, deflate, deflate_global,
                            bad, decomp, error, __LINE__,
                            zbuf.avail_in, zbuf.avail_out, zbuf.total_out);
                        goto bad;
                }
        }

        result = count = zbuf.total_out;

        *out = malloc(result, M_CRYPTO_DATA, M_NOWAIT);
        if (*out == NULL) {
                SDT_PROBE6(opencrypto, deflate, deflate_global, bad,
                    decomp, 0, __LINE__, 0, 0, 0);
                goto bad;
        }
        if (decomp)
                inflateEnd(&zbuf);
        else
                deflateEnd(&zbuf);
        output = *out;
        for (bufp = bufh; bufp != NULL; ) {
                if (count > bufp->size) {
                        struct deflate_buf *p;

                        bcopy(bufp->data, *out, bufp->size);
                        *out += bufp->size;
                        count -= bufp->size;
                        p = bufp;
                        bufp = bufp->next;
                        free(p, M_CRYPTO_DATA);
                } else {
                        /* It should be the last buffer. */
                        bcopy(bufp->data, *out, count);
                        *out += count;
                        free(bufp, M_CRYPTO_DATA);
                        bufp = NULL;
                        count = 0;
                }
        }
        *out = output;
        SDT_PROBE2(opencrypto, deflate, deflate_global, return, decomp, result);
        return result;

bad:
        if (decomp)
                inflateEnd(&zbuf);
        else
                deflateEnd(&zbuf);
        for (bufp = bufh; bufp != NULL; ) {
                struct deflate_buf *p;

                p = bufp;
                bufp = bufp->next;
                free(p, M_CRYPTO_DATA);
        }
bad2:
        *out = NULL;
        return 0;
}