/* $OpenBSD: f_int.c,v 1.20 2018/05/13 13:48:08 jsing Exp $ */
/* 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 <openssl/asn1.h>
#include <openssl/buffer.h>
#include <openssl/err.h>

int
i2a_ASN1_INTEGER(BIO *bp, const ASN1_INTEGER *a)
{
	int i, n = 0;
	static const char h[] = "0123456789ABCDEF";
	char buf[2];

	if (a == NULL)
		return (0);

	if (a->type & V_ASN1_NEG) {
		if (BIO_write(bp, "-", 1) != 1)
			goto err;
		n = 1;
	}

	if (a->length == 0) {
		if (BIO_write(bp, "00", 2) != 2)
			goto err;
		n += 2;
	} 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;
			}
			buf[0] = h[((unsigned char)a->data[i] >> 4) & 0x0f];
			buf[1] = h[((unsigned char)a->data[i]) & 0x0f];
			if (BIO_write(bp, buf, 2) != 2)
				goto err;
			n += 2;
		}
	}
	return (n);

err:
	return (-1);
}

int
a2i_ASN1_INTEGER(BIO *bp, ASN1_INTEGER *bs, char *buf, int size)
{
	int ret = 0;
	int i, j,k, m,n, again, bufsize;
	unsigned char *s = NULL, *sp;
	unsigned char *bufp;
	int num = 0, slen = 0, first = 1;

	bs->type = V_ASN1_INTEGER;

	bufsize = BIO_gets(bp, buf, size);
	for (;;) {
		if (bufsize < 1)
			goto err_sl;
		i = bufsize;
		if (buf[i - 1] == '\n')
			buf[--i] = '\0';
		if (i == 0)
			goto err_sl;
		if (buf[i - 1] == '\r')
			buf[--i] = '\0';
		if (i == 0)
			goto err_sl;
		again = (buf[i - 1] == '\\');

		for (j = 0; j < i; j++) {
			if (!(((buf[j] >= '0') && (buf[j] <= '9')) ||
			    ((buf[j] >= 'a') && (buf[j] <= 'f')) ||
			    ((buf[j] >= 'A') && (buf[j] <= 'F')))) {
				i = j;
				break;
			}
		}
		buf[i] = '\0';
		/* We have now cleared all the crap off the end of the
		 * line */
		if (i < 2)
			goto err_sl;

		bufp = (unsigned char *)buf;
		if (first) {
			first = 0;
			if ((bufp[0] == '0') && (buf[1] == '0')) {
				bufp += 2;
				i -= 2;
			}
		}
		k = 0;
		i -= again;
		if (i % 2 != 0) {
			ASN1error(ASN1_R_ODD_NUMBER_OF_CHARS);
			goto err;
		}
		i /= 2;
		if (num + i > slen) {
			if ((sp = recallocarray(s, slen, num + i, 1)) == NULL) {
				ASN1error(ERR_R_MALLOC_FAILURE);
				goto err;
			}
			s = sp;
			slen = num + i;
		}
		for (j = 0; j < i; j++, k += 2) {
			for (n = 0; n < 2; n++) {
				m = bufp[k + n];
				if ((m >= '0') && (m <= '9'))
					m -= '0';
				else if ((m >= 'a') && (m <= 'f'))
					m = m - 'a' + 10;
				else if ((m >= 'A') && (m <= 'F'))
					m = m - 'A' + 10;
				else {
					ASN1error(ASN1_R_NON_HEX_CHARACTERS);
					goto err;
				}
				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_sl:
	ASN1error(ASN1_R_SHORT_LINE);
err:
	free(s);
	return (ret);
}
