/* crypto/bio/bss_mem.c */

/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

 * All rights reserved.

 *

 * This package is an SSL implementation written

 * by Eric Young (eay@cryptsoft.com).

 * The implementation was written so as to conform with Netscapes SSL.

 *

 * This library is free for commercial and non-commercial use as long as

 * the following conditions are aheared to.  The following conditions

 * apply to all code found in this distribution, be it the RC4, RSA,

 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation

 * included with this distribution is covered by the same copyright terms

 * except that the holder is Tim Hudson (tjh@cryptsoft.com).

 *

 * Copyright remains Eric Young's, and as such any Copyright notices in

 * the code are not to be removed.

 * If this package is used in a product, Eric Young should be given attribution

 * as the author of the parts of the library used.

 * This can be in the form of a textual message at program startup or

 * in documentation (online or textual) provided with the package.

 *

 * 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 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 cryptographic software written by

 *     Eric Young (eay@cryptsoft.com)"

 *    The word 'cryptographic' can be left out if the rouines from the library

 *    being used are not cryptographic related :-).

 * 4. If you include any Windows specific code (or a derivative thereof) from

 *    the apps directory (application code) you must include an acknowledgement:

 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"

 *

 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 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.

 *

 * The licence and distribution terms for any publically available version or

 * derivative of this code cannot be changed.  i.e. this code cannot simply be

 * copied and put under another distribution licence

 * [including the GNU Public Licence.]

 */

#include <stdio.h>

#include <errno.h>

#include "cryptlib.h"

#include <openssl/bio.h>

static int mem_write(BIO *h, const char *buf, int num);

static int mem_read(BIO *h, char *buf, int size);

static int mem_puts(BIO *h, const char *str);

static int mem_gets(BIO *h, char *str, int size);

static long mem_ctrl(BIO *h, int cmd, long arg1, void *arg2);

static int mem_new(BIO *h);

static int mem_free(BIO *data);

static BIO_METHOD mem_method = {

    BIO_TYPE_MEM,

    "memory buffer",

    mem_write,

    mem_read,

    mem_puts,

    mem_gets,

    mem_ctrl,

    mem_new,

    mem_free,

    NULL,

};

/*

 * bio->num is used to hold the value to return on 'empty', if it is 0,

 * should_retry is not set

 */

BIO_METHOD *BIO_s_mem(void)

{

    return (&mem_method);

}

BIO *BIO_new_mem_buf(const void *buf, int len)

{

    BIO *ret;

    BUF_MEM *b;

    size_t sz;

    if (!buf) {

        BIOerr(BIO_F_BIO_NEW_MEM_BUF, BIO_R_NULL_PARAMETER);

        return NULL;

    }

    sz = (len < 0) ? strlen(buf) : (size_t)len;

    if (!(ret = BIO_new(BIO_s_mem())))

        return NULL;

    b = (BUF_MEM *)ret->ptr;

    /* Cast away const and trust in the MEM_RDONLY flag. */

    b->data = (void *)buf;

    b->length = sz;

    b->max = sz;

    ret->flags |= BIO_FLAGS_MEM_RDONLY;

    /* Since this is static data retrying wont help */

    ret->num = 0;

    return ret;

}

static int mem_new(BIO *bi)

{

    BUF_MEM *b;

    if ((b = BUF_MEM_new()) == NULL)

        return (0);

    bi->shutdown = 1;

    bi->init = 1;

    bi->num = -1;

    bi->ptr = (char *)b;

    return (1);

}

static int mem_free(BIO *a)

{

    if (a == NULL)

        return (0);

    if (a->shutdown) {

        if ((a->init) && (a->ptr != NULL)) {

            BUF_MEM *b;

            b = (BUF_MEM *)a->ptr;

            if (a->flags & BIO_FLAGS_MEM_RDONLY)

                b->data = NULL;

            BUF_MEM_free(b);

            a->ptr = NULL;

        }

    }

    return (1);

}

static int mem_read(BIO *b, char *out, int outl)

{

    int ret = -1;

    BUF_MEM *bm;

    bm = (BUF_MEM *)b->ptr;

    BIO_clear_retry_flags(b);

    ret = (outl >= 0 && (size_t)outl > bm->length) ? (int)bm->length : outl;

    if ((out != NULL) && (ret > 0)) {

        memcpy(out, bm->data, ret);

        bm->length -= ret;

        if (b->flags & BIO_FLAGS_MEM_RDONLY)

            bm->data += ret;

        else {

            memmove(&(bm->data[0]), &(bm->data[ret]), bm->length);

        }

    } else if (bm->length == 0) {

        ret = b->num;

        if (ret != 0)

            BIO_set_retry_read(b);

    }

    return (ret);

}

static int mem_write(BIO *b, const char *in, int inl)

{

    int ret = -1;

    int blen;

    BUF_MEM *bm;

    bm = (BUF_MEM *)b->ptr;

    if (in == NULL) {

        BIOerr(BIO_F_MEM_WRITE, BIO_R_NULL_PARAMETER);

        goto end;

    }

    if (b->flags & BIO_FLAGS_MEM_RDONLY) {

        BIOerr(BIO_F_MEM_WRITE, BIO_R_WRITE_TO_READ_ONLY_BIO);

        goto end;

    }

    BIO_clear_retry_flags(b);

    blen = bm->length;

    if (BUF_MEM_grow_clean(bm, blen + inl) != (blen + inl))

        goto end;

    memcpy(&(bm->data[blen]), in, inl);

    ret = inl;

 end:

    return (ret);

}

static long mem_ctrl(BIO *b, int cmd, long num, void *ptr)

{

    long ret = 1;

    char **pptr;

    BUF_MEM *bm = (BUF_MEM *)b->ptr;

    switch (cmd) {

    case BIO_CTRL_RESET:

        if (bm->data != NULL) {

            /* For read only case reset to the start again */

            if (b->flags & BIO_FLAGS_MEM_RDONLY) {

                bm->data -= bm->max - bm->length;

                bm->length = bm->max;

            } else {

                memset(bm->data, 0, bm->max);

                bm->length = 0;

            }

        }

        break;

    case BIO_CTRL_EOF:

        ret = (long)(bm->length == 0);

        break;

    case BIO_C_SET_BUF_MEM_EOF_RETURN:

        b->num = (int)num;

        break;

    case BIO_CTRL_INFO:

        ret = (long)bm->length;

        if (ptr != NULL) {

            pptr = (char **)ptr;

            *pptr = (char *)&(bm->data[0]);

        }

        break;

    case BIO_C_SET_BUF_MEM:

        mem_free(b);

        b->shutdown = (int)num;

        b->ptr = ptr;

        break;

    case BIO_C_GET_BUF_MEM_PTR:

        if (ptr != NULL) {

            pptr = (char **)ptr;

            *pptr = (char *)bm;

        }

        break;

    case BIO_CTRL_GET_CLOSE:

        ret = (long)b->shutdown;

        break;

    case BIO_CTRL_SET_CLOSE:

        b->shutdown = (int)num;

        break;

    case BIO_CTRL_WPENDING:

        ret = 0L;

        break;

    case BIO_CTRL_PENDING:

        ret = (long)bm->length;

        break;

    case BIO_CTRL_DUP:

    case BIO_CTRL_FLUSH:

        ret = 1;

        break;

    case BIO_CTRL_PUSH:

    case BIO_CTRL_POP:

    default:

        ret = 0;

        break;

    }

    return (ret);

}

static int mem_gets(BIO *bp, char *buf, int size)

{

    int i, j;

    int ret = -1;

    char *p;

    BUF_MEM *bm = (BUF_MEM *)bp->ptr;

    BIO_clear_retry_flags(bp);

    j = bm->length;

    if ((size - 1) < j)

        j = size - 1;

    if (j <= 0) {

        *buf = '\0';

        return 0;

    }

    p = bm->data;

    for (i = 0; i < j; i++) {

        if (p[i] == '\n') {

            i++;

            break;

        }

    }

    /*

     * i is now the max num of bytes to copy, either j or up to

     * and including the first newline

     */

    i = mem_read(bp, buf, i);

    if (i > 0)

        buf[i] = '\0';

    ret = i;

    return (ret);

}

static int mem_puts(BIO *bp, const char *str)

{

    int n, ret;

    n = strlen(str);

    ret = mem_write(bp, str, n);

    /* memory semantics is that it will always work */

    return (ret);

}