protocols/tcp/tcp.cpp

56 // The TCP header length is at most 60 bytes (0xf * 4).
84 bump_option(tcp_option *&option, size_t &length)
87 		length++;
90 		length += option->length;
91 		option = (tcp_option *)((uint8 *)option + option->length);
103 	size_t length = 0;
105 	if (segment.max_segment_size > 0 && length + 8 <= bufferSize) {
107 		option->length = 4;
109 		bump_option(option, length);
113 		&& length + 12 <= bufferSize) {
117 			option->length = 2;
118 			bump_option(option, length);
122 			bump_option(option, length);
124 			bump_option(option, length);
127 		option->length = 10;
130 		bump_option(option, length);
132 		&& length + 4 <= bufferSize) {
135 		bump_option(option, length);
137 		bump_option(option, length);
139 		option->length = 2;
140 		bump_option(option, length);
144 		&& length + 4 <= bufferSize) {
147 		bump_option(option, length);
150 		option->length = 3;
152 		bump_option(option, length);
156 		int sackCount = ((int)(bufferSize - length) - 4) / sizeof(tcp_sack);
162 			bump_option(option, length);
164 			bump_option(option, length);
166 			option->length = 2 + sackCount * sizeof(tcp_sack);
168 			bump_option(option, length);
172 	if ((length & 3) == 0) {
174 		return length;
178 	return (length + 3) & ~3;
179 		// bump to a multiple of 4 length
204 		int32 length = -1;
209 				length = 1;
212 				if (option->length == 4 && size >= 4)
216 				if (option->length == 3 && size >= 3) {
222 				if (option->length == 10 && size >= 10) {
230 				if (option->length == 2 && size >= 2)
234 				if (size >= option->length) {
236 					segment.sackCount = min_c((option->length - 2)
248 		if (length < 0) {
249 			length = option->length;
250 			if (length == 0 || length > (ssize_t)size)
254 		option = (tcp_option *)((uint8 *)option + length);
255 		size -= length;
446 	size_t length = 0;
449 		length += 4;
452 		length += 12;
454 		length += 4;
457 		length += 4;
460 		int sackCount = min_c((int)((kMaxOptionSize - length - 4)
463 			length += 4 + sackCount * sizeof(tcp_sack);
466 	if ((length & 3) == 0)
467 		return length;
469 	return (length + 3) & ~3;
571 	const void* _value, int length)
577 			if (length != sizeof(int))
592 		return protocol->SetOption(option, _value, length);
595 		_value, length);