/*

 * Copyright 1995-2024 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <stdio.h>

#include "crypto/ctype.h"

#include "internal/cryptlib.h"

#include <openssl/buffer.h>

#include <openssl/asn1.h>

int i2a_ASN1_STRING(BIO *bp, const ASN1_STRING *a, int type)

{

    int i, n = 0;

    char buf[2];

    if (a == NULL)

        return 0;

    if (a->length == 0) {

        if (BIO_write(bp, "0", 1) != 1)

            goto err;

        n = 1;

    } else {

        for (i = 0; i < a->length; i++) {

            if ((i != 0) && (i % 35 == 0)) {

                if (BIO_write(bp, "\\\n", 2) != 2)

                    goto err;

                n += 2;

            }

            ossl_to_hex(buf, a->data[i]);

            if (BIO_write(bp, buf, 2) != 2)

                goto err;

            n += 2;

        }

    }

    return n;

 err:

    return -1;

}

int a2i_ASN1_STRING(BIO *bp, ASN1_STRING *bs, char *buf, int size)

{

    int i, j, k, m, n, again, bufsize;

    unsigned char *s = NULL, *sp;

    unsigned char *bufp;

    int num = 0, slen = 0, first = 1;

    bufsize = BIO_gets(bp, buf, size);

    for (;;) {

        if (bufsize < 1) {

            if (first)

                break;

            else

                goto err;

        }

        first = 0;

        i = bufsize;

        if (buf[i - 1] == '\n')

            buf[--i] = '\0';

        if (i == 0)

            goto err;

        if (buf[i - 1] == '\r')

            buf[--i] = '\0';

        if (i == 0)

            goto err;

        again = (buf[i - 1] == '\\');

        for (j = i - 1; j > 0; j--) {

            if (!ossl_isxdigit(buf[j])) {

                i = j;

                break;

            }

        }

        buf[i] = '\0';

        /*

         * We have now cleared all the crap off the end of the line

         */

        if (i < 2)

            goto err;

        bufp = (unsigned char *)buf;

        k = 0;

        i -= again;

        if (i % 2 != 0) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_ODD_NUMBER_OF_CHARS);

            OPENSSL_free(s);

            return 0;

        }

        i /= 2;

        if (num + i > slen) {

            sp = OPENSSL_realloc(s, (unsigned int)num + i * 2);

            if (sp == NULL) {

                OPENSSL_free(s);

                return 0;

            }

            s = sp;

            slen = num + i * 2;

        }

        for (j = 0; j < i; j++, k += 2) {

            for (n = 0; n < 2; n++) {

                m = OPENSSL_hexchar2int(bufp[k + n]);

                if (m < 0) {

                    ERR_raise(ERR_LIB_ASN1, ASN1_R_NON_HEX_CHARACTERS);

                    OPENSSL_free(s);

                    return 0;

                }

                s[num + j] <<= 4;

                s[num + j] |= m;

            }

        }

        num += i;

        if (again)

            bufsize = BIO_gets(bp, buf, size);

        else

            break;

    }

    bs->length = num;

    bs->data = s;

    return 1;

 err:

    ERR_raise(ERR_LIB_ASN1, ASN1_R_SHORT_LINE);

    OPENSSL_free(s);

    return 0;

}