/* crypto/asn1/a_d2i_fp.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 <limits.h>

#include "cryptlib.h"

#include <openssl/buffer.h>

#include <openssl/asn1_mac.h>

static int asn1_d2i_read_bio(BIO *in, BUF_MEM **pb);

#ifndef NO_OLD_ASN1

# ifndef OPENSSL_NO_FP_API

void *ASN1_d2i_fp(void *(*xnew) (void), d2i_of_void *d2i, FILE *in, void **x)

{

    BIO *b;

    void *ret;

    if ((b = BIO_new(BIO_s_file())) == NULL) {

        ASN1err(ASN1_F_ASN1_D2I_FP, ERR_R_BUF_LIB);

        return (NULL);

    }

    BIO_set_fp(b, in, BIO_NOCLOSE);

    ret = ASN1_d2i_bio(xnew, d2i, b, x);

    BIO_free(b);

    return (ret);

}

# endif

void *ASN1_d2i_bio(void *(*xnew) (void), d2i_of_void *d2i, BIO *in, void **x)

{

    BUF_MEM *b = NULL;

    const unsigned char *p;

    void *ret = NULL;

    int len;

    len = asn1_d2i_read_bio(in, &b);

    if (len < 0)

        goto err;

    p = (unsigned char *)b->data;

    ret = d2i(x, &p, len);

 err:

    if (b != NULL)

        BUF_MEM_free(b);

    return (ret);

}

#endif

void *ASN1_item_d2i_bio(const ASN1_ITEM *it, BIO *in, void *x)

{

    BUF_MEM *b = NULL;

    const unsigned char *p;

    void *ret = NULL;

    int len;

    len = asn1_d2i_read_bio(in, &b);

    if (len < 0)

        goto err;

    p = (const unsigned char *)b->data;

    ret = ASN1_item_d2i(x, &p, len, it);

 err:

    if (b != NULL)

        BUF_MEM_free(b);

    return (ret);

}

#ifndef OPENSSL_NO_FP_API

void *ASN1_item_d2i_fp(const ASN1_ITEM *it, FILE *in, void *x)

{

    BIO *b;

    char *ret;

    if ((b = BIO_new(BIO_s_file())) == NULL) {

        ASN1err(ASN1_F_ASN1_ITEM_D2I_FP, ERR_R_BUF_LIB);

        return (NULL);

    }

    BIO_set_fp(b, in, BIO_NOCLOSE);

    ret = ASN1_item_d2i_bio(it, b, x);

    BIO_free(b);

    return (ret);

}

#endif

#define HEADER_SIZE   8

#define ASN1_CHUNK_INITIAL_SIZE (16 * 1024)

static int asn1_d2i_read_bio(BIO *in, BUF_MEM **pb)

{

    BUF_MEM *b;

    unsigned char *p;

    int i;

    ASN1_const_CTX c;

    size_t want = HEADER_SIZE;

    int eos = 0;

    size_t off = 0;

    size_t len = 0;

    b = BUF_MEM_new();

    if (b == NULL) {

        ASN1err(ASN1_F_ASN1_D2I_READ_BIO, ERR_R_MALLOC_FAILURE);

        return -1;

    }

    ERR_clear_error();

    for (;;) {

        if (want >= (len - off)) {

            want -= (len - off);

            if (len + want < len || !BUF_MEM_grow_clean(b, len + want)) {

                ASN1err(ASN1_F_ASN1_D2I_READ_BIO, ERR_R_MALLOC_FAILURE);

                goto err;

            }

            i = BIO_read(in, &(b->data[len]), want);

            if ((i < 0) && ((len - off) == 0)) {

                ASN1err(ASN1_F_ASN1_D2I_READ_BIO, ASN1_R_NOT_ENOUGH_DATA);

                goto err;

            }

            if (i > 0) {

                if (len + i < len) {

                    ASN1err(ASN1_F_ASN1_D2I_READ_BIO, ASN1_R_TOO_LONG);

                    goto err;

                }

                len += i;

            }

        }

        /* else data already loaded */

        p = (unsigned char *)&(b->data[off]);

        c.p = p;

        c.inf = ASN1_get_object(&(c.p), &(c.slen), &(c.tag), &(c.xclass),

                                len - off);

        if (c.inf & 0x80) {

            unsigned long e;

            e = ERR_GET_REASON(ERR_peek_error());

            if (e != ASN1_R_TOO_LONG)

                goto err;

            else

                ERR_clear_error(); /* clear error */

        }

        i = c.p - p;            /* header length */

        off += i;               /* end of data */

        if (c.inf & 1) {

            /* no data body so go round again */

            eos++;

            if (eos < 0) {

                ASN1err(ASN1_F_ASN1_D2I_READ_BIO, ASN1_R_HEADER_TOO_LONG);

                goto err;

            }

            want = HEADER_SIZE;

        } else if (eos && (c.slen == 0) && (c.tag == V_ASN1_EOC)) {

            /* eos value, so go back and read another header */

            eos--;

            if (eos <= 0)

                break;

            else

                want = HEADER_SIZE;

        } else {

            /* suck in c.slen bytes of data */

            want = c.slen;

            if (want > (len - off)) {

                size_t chunk_max = ASN1_CHUNK_INITIAL_SIZE;

                want -= (len - off);

                if (want > INT_MAX /* BIO_read takes an int length */  ||

                    len + want < len) {

                    ASN1err(ASN1_F_ASN1_D2I_READ_BIO, ASN1_R_TOO_LONG);

                    goto err;

                }

                while (want > 0) {

                    /*

                     * Read content in chunks of increasing size

                     * so we can return an error for EOF without

                     * having to allocate the entire content length

                     * in one go.

                     */

                    size_t chunk = want > chunk_max ? chunk_max : want;

                    if (!BUF_MEM_grow_clean(b, len + chunk)) {

                        ASN1err(ASN1_F_ASN1_D2I_READ_BIO, ERR_R_MALLOC_FAILURE);

                        goto err;

                    }

                    want -= chunk;

                    while (chunk > 0) {

                        i = BIO_read(in, &(b->data[len]), chunk);

                        if (i <= 0) {

                            ASN1err(ASN1_F_ASN1_D2I_READ_BIO,

                                    ASN1_R_NOT_ENOUGH_DATA);

                            goto err;

                        }

                    /*

                     * This can't overflow because |len+want| didn't

                     * overflow.

                     */

                        len += i;

                        chunk -= i;

                    }

                    if (chunk_max < INT_MAX/2)

                        chunk_max *= 2;

                }

            }

            if (off + c.slen < off) {

                ASN1err(ASN1_F_ASN1_D2I_READ_BIO, ASN1_R_TOO_LONG);

                goto err;

            }

            off += c.slen;

            if (eos <= 0) {

                break;

            } else

                want = HEADER_SIZE;

        }

    }

    if (off > INT_MAX) {

        ASN1err(ASN1_F_ASN1_D2I_READ_BIO, ASN1_R_TOO_LONG);

        goto err;

    }

    *pb = b;

    return off;

 err:

    if (b != NULL)

        BUF_MEM_free(b);

    return -1;

}