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[KERNEL] Fix IPv4 packet buffer structuring

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git-svn-id: svn://kolibrios.org@9799 a494cfbc-eb01-0410-851d-a64ba20cac60
This commit is contained in:
Magomed Kostoev (mkostoevr) 2022-05-02 10:35:07 +00:00
parent 33f685c41e
commit 52a5b1bf6e
1 changed files with 24 additions and 24 deletions
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48
kernel/trunk/network/IPv4.inc
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@ -393,20 +393,20 @@ ipv4_input:
mov esi, [esi + IPv4_FRAGMENT_slot.ptr]
or edi, -1
.find_last_entry: ; The following routine will try to find the last entry
cmp edi, [esi + IPv4_FRAGMENT_entry.PrevPtr]
cmp edi, [esi + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.PrevPtr]
jne .destroy_slot ; Damn, something screwed up, remove the whole slot (and free buffers too if possible!)
mov edi, esi
mov esi, [esi + IPv4_FRAGMENT_entry.NextPtr]
mov esi, [esi + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.NextPtr]
cmp esi, -1
jne .find_last_entry
; We found the last entry (pointer is now in edi)
; We are going to overwrite the ethernet header in received packet with a FRAGMENT_entry structure
pop eax ; pointer to packet
mov [edi + IPv4_FRAGMENT_entry.NextPtr], eax ; update pointer of previous entry to the new entry
mov [eax + IPv4_FRAGMENT_entry.NextPtr], -1
mov [eax + IPv4_FRAGMENT_entry.PrevPtr], edi
mov [eax + IPv4_FRAGMENT_entry.Owner], ebx
mov [edi + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.NextPtr], eax ; update pointer of previous entry to the new entry
mov [eax + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.NextPtr], -1
mov [eax + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.PrevPtr], edi
mov [eax + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.Owner], ebx
ret
@ -437,9 +437,9 @@ ipv4_input:
pop eax
mov [esi + IPv4_FRAGMENT_slot.ptr], eax
; Now, replace ethernet header in original buffer with a FRAGMENT_entry structure
mov [eax + IPv4_FRAGMENT_entry.NextPtr], -1
mov [eax + IPv4_FRAGMENT_entry.PrevPtr], -1
mov [eax + IPv4_FRAGMENT_entry.Owner], ebx
mov [eax + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.NextPtr], -1
mov [eax + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.PrevPtr], -1
mov [eax + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.Owner], ebx
ret
@ -460,27 +460,27 @@ ipv4_input:
or edi, -1
.count_bytes:
cmp [esi + IPv4_FRAGMENT_entry.PrevPtr], edi
cmp [esi + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.PrevPtr], edi
jne .destroy_slot_pop ; Damn, something screwed up, remove the whole slot (and free buffers too if possible!)
mov cx, [esi + sizeof.IPv4_FRAGMENT_entry + IPv4_header.TotalLength] ; Add total length
mov cx, [esi + sizeof.NET_BUFF + sizeof.IPv4_FRAGMENT_entry + IPv4_header.TotalLength] ; Add total length
xchg cl, ch
DEBUGF DEBUG_NETWORK_VERBOSE, "IPv4_input: Packet size=%u\n", cx
add ax, cx
movzx cx, [esi + sizeof.IPv4_FRAGMENT_entry + IPv4_header.VersionAndIHL] ; Sub Header length
movzx cx, [esi + sizeof.NET_BUFF + sizeof.IPv4_FRAGMENT_entry + IPv4_header.VersionAndIHL] ; Sub Header length
and cx, 0x000F
shl cx, 2
DEBUGF DEBUG_NETWORK_VERBOSE, "IPv4_input: Header size=%u\n", cx
sub ax, cx
mov edi, esi
mov esi, [esi + IPv4_FRAGMENT_entry.NextPtr]
mov esi, [esi + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.NextPtr]
cmp esi, -1
jne .count_bytes
mov esi, [esp+4]
mov [edi + IPv4_FRAGMENT_entry.NextPtr], esi ; Add this packet to the chain, this simplifies the following code
mov [esi + IPv4_FRAGMENT_entry.NextPtr], -1
mov [esi + IPv4_FRAGMENT_entry.PrevPtr], edi
mov [esi + IPv4_FRAGMENT_entry.Owner], ebx
mov [edi + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.NextPtr], esi ; Add this packet to the chain, this simplifies the following code
mov [esi + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.NextPtr], -1
mov [esi + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.PrevPtr], edi
mov [esi + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.Owner], ebx
mov cx, [edx + IPv4_header.TotalLength] ; Note: This time we dont substract Header length
xchg cl, ch
@ -507,18 +507,18 @@ ipv4_input:
mov edx, [esp+4] ; Get pointer to first fragment entry back in edx
.rebuild_packet_loop:
movzx ecx, [edx + sizeof.IPv4_FRAGMENT_entry + IPv4_header.FlagsAndFragmentOffset] ; Calculate the fragment offset
movzx ecx, [edx + sizeof.NET_BUFF + sizeof.IPv4_FRAGMENT_entry + IPv4_header.FlagsAndFragmentOffset] ; Calculate the fragment offset
xchg cl, ch ; intel byte order
shl cx, 3 ; multiply by 8 and clear first 3 bits
DEBUGF DEBUG_NETWORK_VERBOSE, "IPv4_input: Fragment offset=%u\n", cx
lea edi, [eax + ecx] ; Notice that edi will be equal to eax for first fragment
movzx ebx, [edx + sizeof.IPv4_FRAGMENT_entry + IPv4_header.VersionAndIHL] ; Find header size (in ebx) of fragment
movzx ebx, [edx + sizeof.NET_BUFF + sizeof.IPv4_FRAGMENT_entry + IPv4_header.VersionAndIHL] ; Find header size (in ebx) of fragment
and bx, 0x000F ;
shl bx, 2 ;
lea esi, [edx + sizeof.IPv4_FRAGMENT_entry] ; Set esi to the correct begin of fragment
movzx ecx, [edx + sizeof.IPv4_FRAGMENT_entry + IPv4_header.TotalLength] ; Calculate total length of fragment
lea esi, [edx + sizeof.NET_BUFF + sizeof.IPv4_FRAGMENT_entry] ; Set esi to the correct begin of fragment
movzx ecx, [edx + sizeof.NET_BUFF + sizeof.IPv4_FRAGMENT_entry + IPv4_header.TotalLength] ; Calculate total length of fragment
xchg cl, ch ; intel byte order
cmp edi, eax ; Is this packet the first fragment ?
@ -537,8 +537,8 @@ ipv4_input:
rep movsb ;
push eax
push [edx + IPv4_FRAGMENT_entry.Owner] ; we need to remeber the owner, in case this is the last packet
push [edx + IPv4_FRAGMENT_entry.NextPtr] ; Set edx to the next pointer
push [edx + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.Owner] ; we need to remeber the owner, in case this is the last packet
push [edx + sizeof.NET_BUFF + IPv4_FRAGMENT_entry.NextPtr] ; Set edx to the next pointer
push edx ; Push pointer to fragment onto stack
DEBUGF DEBUG_NETWORK_VERBOSE, "IPv4_input: Next Fragment: 0x%x\n", edx
call net_buff_free ; free the previous fragment buffer (this uses the value from stack)
@ -1158,4 +1158,4 @@ ipv4_api:
call net_send_event
xor eax, eax
ret
ret