/* For encode.c and decode.c in HEAD/libraries/liblber/ */

int
ber_encode_oid( BerValue *in, BerValue *out )
{
	unsigned char *der;
	unsigned long val;
	unsigned val1;
	int i, j, len;
	char *ptr, *end, *inend;

	assert( in != NULL );
	assert( out != NULL );

	/* This size check could be defeated with negative input (which glibc
	 * accepts even for %u), so we use LONG_MAX as max limit/error mark.
	 */
	if ( !out->bv_val || out->bv_len < in->bv_len )
		return -1;

	/* OIDs must have at least two components: <0-1>.<0-39> or 2.<any> */
	if ( sscanf( in->bv_val, "%u.%lu%n", &val1, &val, &len ) != 2 )
		return -1;
	if ( val1 < 2 ? val > 39 : (val1 > 2 || val >= LONG_MAX) )
		return -1;
	val += val1 * 40;

	ptr = in->bv_val + len;
	inend = in->bv_val + in->bv_len;
	der = (unsigned char *) out->bv_val;
	for (;;) {
		len = 0;
		do {
			der[len++] = (val & 0x7f) | 0x80;
		} while ( (val >>= 7) != 0 );
		der[0] &= 0x7f;
		for ( i = 0, j = len; i < --j; i++ ) {
			unsigned char tmp = der[i];
			der[i] = der[j];
			der[j] = tmp;
		}
		der += len;

		if ( ptr >= inend ) break;
		if ( *ptr++ != '.' ) return -1;
		val = strtol( ptr, &end, 10 );
		if ( ptr == end || val >= LONG_MAX ) return -1;
		ptr = end;
	}

	out->bv_len = (char *)der - out->bv_val;
	return 0;
}

int
ber_decode_oid( BerValue *in, BerValue *out )
{
	unsigned char *der;
	unsigned long val;
	unsigned val1;
	ber_len_t i;
	char *ptr;

	assert( in != NULL );
	assert( out != NULL );

	/* 4 chars per inbyte + \0 (needed for input {7f 7f 7f...}) */
	if ( !out->bv_val || out->bv_len <= in->bv_len * 4 )
		return -1;

	ptr = NULL;
	val = 0;
	der = (unsigned char *) in->bv_val;
	for ( i=0; i < in->bv_len; i++ ) {
		if ( val >= (LONG_MAX >> 7) ) /* matches encode.c LONG_MAX limit */
			return -1;
		val = val << 7;
		val |= der[i] & 0x7f;
		if ( !( der[i] & 0x80 )) {
			if ( ptr == NULL ) {
				ptr = out->bv_val;
				val1 = (val < 80 ? val/40 : 2);
				val -= 40*val1;
				ptr += sprintf( ptr, "%u", val1 );
			}
			ptr += sprintf( ptr, ".%lu", val );
			val = 0;
		} else if ( val == 0 ) {
			return -1;	/* subidentifier may not start with 0x80 */
		}
	}
	if ( ptr == NULL || val != 0 )
		return -1;
	out->bv_len = ptr - out->bv_val;
	return 0;
}