WebSVN – Kolibri OS – Blame – /kernel/trunk/network/ip.inc

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2288	clevermous	1	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		2	;; ;;
		3	;; IP.INC ;;
		4	;; ;;
		5	;; IP Processes for Menuet OS TCP/IP stack ;;
		6	;; ;;
		7	;; Version 0.3 29 August 2002 ;;
		8	;; ;;
		9	;; Copyright 2002 Mike Hibbett, mikeh@oceanfree.net ;;
		10	;; ;;
		11	;; See file COPYING for details ;;
		12	;; ;;
		13	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		14
		15	$Revision: 2288 $
		16
		17
		18	; IP underlying protocols numbers
		19	PROTOCOL_ICMP equ 1
		20	PROTOCOL_TCP equ 6
		21	PROTOCOL_UDP equ 17
		22
		23	struc IP_PACKET
		24	{ .VersionAndIHL db ? ;+00 - Version[0-3 bits] and IHL(header length)[4-7 bits]
		25	.TypeOfService db ? ;+01
		26	.TotalLength dw ? ;+02
		27	.Identification dw ? ;+04
		28	.FlagsAndFragmentOffset dw ? ;+06 - Flags[0-2] and FragmentOffset[3-15]
		29	.TimeToLive db ? ;+08
		30	.Protocol db ? ;+09
		31	.HeaderChecksum dw ? ;+10
		32	.SourceAddress dd ? ;+12
		33	.DestinationAddress dd ? ;+16
		34	.DataOrOptional dd ? ;+20
		35	}
		36
		37	virtual at 0
		38	IP_PACKET IP_PACKET
		39	end virtual
		40
		41
		42	;*******************************************************************
		43	; Interface
		44	;
		45	; ip_rx processes all packets received by the network layer
		46	; It calls the appropriate protocol handler
		47	;
		48	;
		49	;
		50	;*******************************************************************
		51
		52
		53	;
		54	; IP Packet after reception - Normal IP packet format
		55	;
		56	; 0 1 2 3
		57	; 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
		58	;
		59	; +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		60	;0 \|Version\| IHL \|Type of Service\| Total Length \|
		61	; +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		62	;4 \| Identification \|Flags\| Fragment Offset \|
		63	; +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		64	;8 \| Time to Live \| Protocol \| Header Checksum \|
		65	; +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		66	;12 \| Source Address \|
		67	; +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		68	;16 \| Destination Address \|
		69	; +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		70	;20 \| Data \|
		71	; +-+-+-.......... -+
		72	;
		73	;
		74	; [smb] attention! according to RFC 791 IP packet may have 'options' sections,
		75	; so we can't simply think, that data have offset 20. We must calculate offset from
		76	; IHL field
		77	;
		78	macro GET_IHL reg, header_addr
		79	{
		80	movzx reg, byte [header_addr]
		81
		82	; we need 4-7 bits, so....
		83	and reg, 0x0000000F
		84
		85	; IHL keeps number of octets, so we need to << 2 'reg'
		86	shl reg, 2
		87	}
		88
		89
		90	include "tcp.inc"
		91	include "udp.inc"
		92	include "icmp.inc"
		93
		94	;***************************************************************************
		95	; Function
		96	; ip_rx
		97	;
		98	; Description
		99	; This is a kernel function, called by stack_handler
		100	; Processes all IP-packets received by the network layer
		101	; It calls the appropriate protocol handler
		102	;
		103	;***************************************************************************
		104	proc ip_rx stdcall
		105	local buffer_number dd ?
		106
		107	; Look for a buffer to tx
		108	mov eax, IPIN_QUEUE
		109	call dequeue
		110	cmp ax, NO_BUFFER
		111	je .exit ; Exit if no buffer available
		112
		113	mov [buffer_number], eax;save buffer number
		114
		115	; convert buffer pointer eax to the absolute address
		116	imul eax, IPBUFFSIZE
		117	add eax, IPbuffs
		118
		119	mov ebx, eax; ebx=pointer to IP_PACKET
		120
		121	; DEBUGF 1, "K : ip_rx - proto: %u\n", [ebx + IP_PACKET.Protocol]:1
		122
		123	; Validate the IP checksum
		124	mov dx, word[ebx + IP_PACKET.HeaderChecksum]
		125	xchg dh, dl ; Get the checksum in intel format
		126
		127	mov [ebx + IP_PACKET.HeaderChecksum], 0; clear checksum field - need to when
		128	; recalculating checksum
		129	; this needs two data pointers and two size #.
		130	; 2nd pointer can be of length 0
		131
		132	GET_IHL ecx, ebx + IP_PACKET.VersionAndIHL ;get packet length in ecx
		133	stdcall checksum_jb, ebx, ecx;buf_ptr, buf_size
		134	cmp dx, ax
		135
		136	; DEBUGF 1, "K : ip_rx - checksums: %x - %x\n", dx, ax
		137
		138	jnz .dump.1;if CHECKSUM isn't valid then dump packet
		139	mov edx, ebx; EDX (IP-BUFFER POINTER) WILL BE USED FOR *_rx HANDLERS BELOW!!!
		140
		141	; DEBUGF 1, "K : ip_rx - dest: %x - %x\n", [ebx + IP_PACKET.DestinationAddress], [stack_ip]
		142
		143	; Validate the IP address, if it isn't broadcast
		144	mov eax, [stack_ip]
		145	cmp dword[ebx + IP_PACKET.DestinationAddress], eax
		146	je @f
		147
		148	; If the IP address is 255.255.255.255, accept it
		149	; - it is a broadcast packet, which we need for dhcp
		150
		151	mov eax, [ebx + IP_PACKET.DestinationAddress]
		152	cmp eax, 0xffffffff
		153	je @f
		154	mov ecx, [stack_ip]
		155	and eax, [subnet_mask]
		156	and ecx, [subnet_mask]
		157	cmp eax, ecx
		158	jne .dump.2
		159	mov eax, [ebx + IP_PACKET.DestinationAddress]
		160	or eax, [subnet_mask]
		161	cmp eax, 0xffffffff
		162	jne .dump.2
		163
		164	@@:
		165	mov al, [ebx + IP_PACKET.VersionAndIHL]
		166	and al, 0x0f;get IHL(header length)
		167	cmp al, 0x05;if IHL!= 5*4(20 bytes)
		168	; DEBUGF 1, "K : ip_rx - ihl: %x - 05\n", al
		169	jnz .dump.3 ;then dump it
		170
		171	; DEBUGF 1, "K : ip_rx - ttl: %x - 00\n", [ebx + IP_PACKET.TimeToLive]:2
		172
		173	cmp [ebx + IP_PACKET.TimeToLive], 0
		174	je .dump.4 ;if TTL==0 then dump it
		175
		176	mov ax, [ebx + IP_PACKET.FlagsAndFragmentOffset]
		177	and ax, 0xFFBF;get flags
		178	; DEBUGF 1, "K : ip_rx - flags: %x - 0000\n", ax
		179	cmp ax, 0 ;if some flags was set then we dump this packet
		180	jnz .dump.5 ;the flags should be used for fragmented packets
		181
		182	; Check the protocol, and call the appropriate handler
		183	; Each handler will re-use or free the queue buffer as appropriate
		184
		185	mov al, [ebx + IP_PACKET.Protocol]
		186
		187	cmp al , PROTOCOL_TCP
		188	jne .not_tcp
		189	; DEBUGF 1,"K : ip_rx - TCP packet\n"
		190	mov eax, dword[buffer_number]
		191	call tcp_rx
		192	jmp .exit
		193
		194	.not_tcp:
		195	cmp al, PROTOCOL_UDP
		196	jne .not_udp
		197	; DEBUGF 1,"K : ip_rx - UDP packet\n"
		198	mov eax, dword[buffer_number]
		199	call udp_rx
		200	jmp .exit
		201
		202	.not_udp:
		203	cmp al, PROTOCOL_ICMP
		204	jne .dump.6 ;protocol ain't supported
		205
		206	; DEBUGF 1,"K : ip_rx - ICMP packet\n"
		207	;GET_IHL ecx, ebx + IP_PACKET.VersionAndIHL ;get packet length in ecx
		208	mov eax, dword[buffer_number]
		209	stdcall icmp_rx, eax, ebx, ecx;buffer_number,IPPacketBase,IPHeaderLength
		210	jmp .exit
		211
		212
		213	.dump.1:
		214	DEBUGF 1, "K : ip_rx - dumped (checksum: 0x%x-0x%x)\n", dx, ax
		215	jmp .dump.x
		216
		217	.dump.2:
		218	DEBUGF 1, "K : ip_rx - dumped (ip: %u.%u.%u.%u)\n", [ebx + IP_PACKET.DestinationAddress + 0]:1, [ebx + IP_PACKET.DestinationAddress + 1]:1, [ebx + IP_PACKET.DestinationAddress + 2]:1, [ebx + IP_PACKET.DestinationAddress + 3]:1
		219	jmp .dump.x
		220
		221	.dump.3:
		222	DEBUGF 1, "K : ip_rx - dumped (ihl: %u)\n", al
		223	jmp .dump.x
		224
		225	.dump.4:
		226	DEBUGF 1, "K : ip_rx - dumped (ttl: %u)\n", [ebx + IP_PACKET.TimeToLive]
		227	jmp .dump.x
		228
		229	.dump.5:
		230	DEBUGF 1, "K : ip_rx - dumped (flags: 0x%x)\n", ax
		231	jmp .dump.x
		232
		233	.dump.6:
		234	DEBUGF 1, "K : ip_rx - dumped (proto: %u)\n", [ebx + IP_PACKET.Protocol]:1
		235
		236	.dump.x:
		237	inc dword[dumped_rx_count]
		238	mov eax, [buffer_number]
		239	call freeBuff
		240
		241	.exit:
		242	ret
		243	endp
		244

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(root)/kernel/trunk/network/ip.inc @ 3539 – Rev 2288