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asn1/ber_tlv_length.c  view on Meta::CPAN

		return skip;
	}

	/*
	 * Indefinite length!
	 */
	ASN_DEBUG("Skipping indefinite length");
	for(skip = ll, ptr = ((const char *)ptr) + ll, size -= ll;;) {
		ber_tlv_tag_t tag;

		/* Fetch the tag */
		tl = ber_fetch_tag(ptr, size, &tag);
		if(tl <= 0) return tl;

		ll = ber_skip_length(opt_codec_ctx,
			BER_TLV_CONSTRUCTED(ptr),
			((const char *)ptr) + tl, size - tl);
		if(ll <= 0) return ll;

		skip += tl + ll;

		/*
		 * This may be the end of the indefinite length structure,
		 * two consecutive 0 octets.
		 * Check if it is true.
		 */
		if(((const uint8_t *)ptr)[0] == 0
		&& ((const uint8_t *)ptr)[1] == 0)
			return skip;

		ptr = ((const char *)ptr) + tl + ll;
		size -= tl + ll;
 	}

	/* UNREACHABLE */
}

size_t
der_tlv_length_serialize(ber_tlv_len_t len, void *bufp, size_t size) {
	size_t required_size;	/* Size of len encoding */
	uint8_t *buf = (uint8_t *)bufp;
	uint8_t *end;
	size_t i;

	if(len <= 127) {
		/* Encoded in 1 octet */
		if(size) *buf = (uint8_t)len;
		return 1;
	}

	/*
	 * Compute the size of the subsequent bytes.
	 */
	for(required_size = 1, i = 8; i < 8 * sizeof(len); i += 8) {
		if(len >> i)
			required_size++;
		else
			break;
	}

	if(size <= required_size)
		return required_size + 1;

	*buf++ = (uint8_t)(0x80 | required_size);  /* Length of the encoding */

	/*
	 * Produce the len encoding, space permitting.
	 */
	end = buf + required_size;
	for(i -= 8; buf < end; i -= 8, buf++)
		*buf = (uint8_t)(len >> i);

	return required_size + 1;
}