/** @file
Copyright (c) 2005 - 2006, Intel Corporation
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
Module Name:
NetBuffer.c
Abstract:
**/
#include <PiDxe.h>
#include <Library/NetLib.h>
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/MemoryAllocationLib.h>
/**
Allocate and build up the sketch for a NET_BUF. The net buffer allocated
has the BlockOpNum's NET_BLOCK_OP, and its associated NET_VECTOR has the
BlockNum's NET_BLOCK.
@param BlockNum The number of NET_BLOCK in the Vector of net buffer
@param BlockOpNum The number of NET_BLOCK_OP in the net buffer
@retval * Pointer to the allocated NET_BUF. If NULL the
allocation failed due to resource limit.
**/
STATIC
NET_BUF *
NetbufAllocStruct (
IN UINT32 BlockNum,
IN UINT32 BlockOpNum
)
{
NET_BUF *Nbuf;
NET_VECTOR *Vector;
ASSERT (BlockOpNum >= 1);
//
// Allocate three memory blocks.
//
Nbuf = NetAllocateZeroPool (NET_BUF_SIZE (BlockOpNum));
if (Nbuf == NULL) {
return NULL;
}
Nbuf->Signature = NET_BUF_SIGNATURE;
Nbuf->RefCnt = 1;
Nbuf->BlockOpNum = BlockOpNum;
NetListInit (&Nbuf->List);
if (BlockNum != 0) {
Vector = NetAllocateZeroPool (NET_VECTOR_SIZE (BlockNum));
if (Vector == NULL) {
goto FreeNbuf;
}
Vector->Signature = NET_VECTOR_SIGNATURE;
Vector->RefCnt = 1;
Vector->BlockNum = BlockNum;
Nbuf->Vector = Vector;
}
return Nbuf;
FreeNbuf:
NetFreePool (Nbuf);
return NULL;
}
/**
Allocate a single block NET_BUF. Upon allocation, all the
free space is in the tail room.
@param Len The length of the block.
@retval * Pointer to the allocated NET_BUF. If NULL the
allocation failed due to resource limit.
**/
NET_BUF *
NetbufAlloc (
IN UINT32 Len
)
{
NET_BUF *Nbuf;
NET_VECTOR *Vector;
UINT8 *Bulk;
ASSERT (Len > 0);
Nbuf = NetbufAllocStruct (1, 1);
if (Nbuf == NULL) {
return NULL;
}
Bulk = NetAllocatePool (Len);
if (Bulk == NULL) {
goto FreeNBuf;
}
Vector = Nbuf->Vector;
Vector->Len = Len;
Vector->Block[0].Bulk = Bulk;
Vector->Block[0].Len = Len;
Nbuf->BlockOp[0].BlockHead = Bulk;
Nbuf->BlockOp[0].BlockTail = Bulk + Len;
Nbuf->BlockOp[0].Head = Bulk;
Nbuf->BlockOp[0].Tail = Bulk;
Nbuf->BlockOp[0].Size = 0;
return Nbuf;
FreeNBuf:
NetFreePool (Nbuf);
return NULL;
}
/**
Free the vector
@param Vector Pointer to the NET_VECTOR to be freed.
@return None.
**/
STATIC
VOID
NetbufFreeVector (
IN NET_VECTOR *Vector
)
{
UINT32 Index;
NET_CHECK_SIGNATURE (Vector, NET_VECTOR_SIGNATURE);
ASSERT (Vector->RefCnt > 0);
Vector->RefCnt--;
if (Vector->RefCnt > 0) {
return;
}
if (Vector->Free != NULL) {
//
// Call external free function to free the vector if it
// isn't NULL. If NET_VECTOR_OWN_FIRST is set, release the
// first block since it is allocated by us
//
if (Vector->Flag & NET_VECTOR_OWN_FIRST) {
NetFreePool (Vector->Block[0].Bulk);
}
Vector->Free (Vector->Arg);
} else {
//
// Free each memory block associated with the Vector
//
for (Index = 0; Index < Vector->BlockNum; Index++) {
NetFreePool (Vector->Block[Index].Bulk);
}
}
NetFreePool (Vector);
}
/**
Free the buffer and its associated NET_VECTOR.
@param Nbuf Pointer to the NET_BUF to be freed.
@return None.
**/
VOID
NetbufFree (
IN NET_BUF *Nbuf
)
{
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
ASSERT (Nbuf->RefCnt > 0);
Nbuf->RefCnt--;
if (Nbuf->RefCnt == 0) {
//
// Update Vector only when NBuf is to be released. That is,
// all the sharing of Nbuf increse Vector's RefCnt by one
//
NetbufFreeVector (Nbuf->Vector);
NetFreePool (Nbuf);
}
}
/**
Create a copy of NET_BUF that share the associated NET_DATA.
@param Nbuf Pointer to the net buffer to be cloned.
@retval * Pointer to the cloned net buffer.
**/
NET_BUF *
NetbufClone (
IN NET_BUF *Nbuf
)
{
NET_BUF *Clone;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
Clone = NetAllocatePool (NET_BUF_SIZE (Nbuf->BlockOpNum));
if (Clone == NULL) {
return NULL;
}
Clone->Signature = NET_BUF_SIGNATURE;
Clone->RefCnt = 1;
NetListInit (&Clone->List);
Clone->Ip = Nbuf->Ip;
Clone->Tcp = Nbuf->Tcp;
NetCopyMem (Clone->ProtoData, Nbuf->ProtoData, NET_PROTO_DATA);
NET_GET_REF (Nbuf->Vector);
Clone->Vector = Nbuf->Vector;
Clone->BlockOpNum = Nbuf->BlockOpNum;
Clone->TotalSize = Nbuf->TotalSize;
NetCopyMem (Clone->BlockOp, Nbuf->BlockOp, sizeof (NET_BLOCK_OP) * Nbuf->BlockOpNum);
return Clone;
}
/**
Create a duplicated copy of Nbuf, data is copied. Also leave some
head space before the data.
@param Nbuf Pointer to the net buffer to be cloned.
@param Duplicate Pointer to the net buffer to duplicate to, if NULL
a new net buffer is allocated.
@param HeadSpace Length of the head space to reserve
@retval * Pointer to the duplicated net buffer.
**/
NET_BUF *
NetbufDuplicate (
IN NET_BUF *Nbuf,
IN NET_BUF *Duplicate OPTIONAL,
IN UINT32 HeadSpace
)
{
UINT8 *Dst;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
if (Duplicate == NULL) {
Duplicate = NetbufAlloc (Nbuf->TotalSize + HeadSpace);
}
if (Duplicate == NULL) {
return NULL;
}
//
// Don't set the IP and TCP head point, since it is most
// like that they are pointing to the memory of Nbuf.
//
NetCopyMem (Duplicate->ProtoData, Nbuf->ProtoData, NET_PROTO_DATA);
NetbufReserve (Duplicate, HeadSpace);
Dst = NetbufAllocSpace (Duplicate, Nbuf->TotalSize, NET_BUF_TAIL);
NetbufCopy (Nbuf, 0, Nbuf->TotalSize, Dst);
return Duplicate;
}
/**
Free a list of net buffers.
@param Head Pointer to the head of linked net buffers.
@return None.
**/
VOID
NetbufFreeList (
IN NET_LIST_ENTRY *Head
)
{
NET_LIST_ENTRY *Entry;
NET_LIST_ENTRY *Next;
NET_BUF *Nbuf;
Entry = Head->ForwardLink;
NET_LIST_FOR_EACH_SAFE (Entry, Next, Head) {
Nbuf = NET_LIST_USER_STRUCT (Entry, NET_BUF, List);
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
NetListRemoveEntry (Entry);
NetbufFree (Nbuf);
}
ASSERT (NetListIsEmpty (Head));
}
/**
Get the position of some byte in the net buffer. This can be used
to, for example, retrieve the IP header in the packet. It also
returns the fragment that contains the byte which is used mainly by
the buffer implementation itself.
@param Nbuf Pointer to the net buffer.
@param Offset The index or offset of the byte
@param Index Index of the fragment that contains the block
@retval * Pointer to the nth byte of data in the net buffer.
If NULL, there is no such data in the net buffer.
**/
UINT8 *
NetbufGetByte (
IN NET_BUF *Nbuf,
IN UINT32 Offset,
OUT UINT32 *Index OPTIONAL
)
{
NET_BLOCK_OP *BlockOp;
UINT32 Loop;
UINT32 Len;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
if (Offset >= Nbuf->TotalSize) {
return NULL;
}
BlockOp = Nbuf->BlockOp;
Len = 0;
for (Loop = 0; Loop < Nbuf->BlockOpNum; Loop++) {
if (Len + BlockOp[Loop].Size <= Offset) {
Len += BlockOp[Loop].Size;
continue;
}
if (Index != NULL) {
*Index = Loop;
}
return BlockOp[Loop].Head + (Offset - Len);
}
return NULL;
}
/**
Set the NET_BLOCK and corresponding NET_BLOCK_OP in
the buffer. All the pointers in NET_BLOCK and NET_BLOCK_OP
are set to the bulk's head and tail respectively. So, this
function alone can't be used by NetbufAlloc.
@param Nbuf Pointer to the net buffer.
@param Bulk Pointer to the data.
@param Len Length of the bulk data.
@param Index The data block index in the net buffer the bulk
data should belong to.
@return None.
**/
STATIC
VOID
NetbufSetBlock (
IN NET_BUF *Nbuf,
IN UINT8 *Bulk,
IN UINT32 Len,
IN UINT32 Index
)
{
NET_BLOCK_OP *BlockOp;
NET_BLOCK *Block;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
NET_CHECK_SIGNATURE (Nbuf->Vector, NET_VECTOR_SIGNATURE);
ASSERT (Index < Nbuf->BlockOpNum);
Block = &(Nbuf->Vector->Block[Index]);
BlockOp = &(Nbuf->BlockOp[Index]);
Block->Len = Len;
Block->Bulk = Bulk;
BlockOp->BlockHead = Bulk;
BlockOp->BlockTail = Bulk + Len;
BlockOp->Head = Bulk;
BlockOp->Tail = Bulk + Len;
BlockOp->Size = Len;
}
/**
Set the NET_BLOCK_OP in the buffer. The corresponding NET_BLOCK
structure is left untouched. Some times, there is no 1:1 relationship
between NET_BLOCK and NET_BLOCK_OP. For example, that in NetbufGetFragment.
@param Nbuf Pointer to the net buffer.
@param Bulk Pointer to the data.
@param Len Length of the bulk data.
@param Index The data block index in the net buffer the bulk
data should belong to.
@return None.
**/
STATIC
VOID
NetbufSetBlockOp (
IN NET_BUF *Nbuf,
IN UINT8 *Bulk,
IN UINT32 Len,
IN UINT32 Index
)
{
NET_BLOCK_OP *BlockOp;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
ASSERT (Index < Nbuf->BlockOpNum);
BlockOp = &(Nbuf->BlockOp[Index]);
BlockOp->BlockHead = Bulk;
BlockOp->BlockTail = Bulk + Len;
BlockOp->Head = Bulk;
BlockOp->Tail = Bulk + Len;
BlockOp->Size = Len;
}
/**
Helper function for NetbufClone. It is necessary because NetbufGetFragment
may allocate the first block to accomodate the HeadSpace and HeadLen. So, it
need to create a new NET_VECTOR. But, we want to avoid data copy by sharing
the old NET_VECTOR.
@param Arg Point to the old NET_VECTOR
@return NONE
**/
STATIC
VOID
NetbufGetFragmentFree (
IN VOID *Arg
)
{
NET_VECTOR *Vector;
Vector = (NET_VECTOR *)Arg;
NetbufFreeVector (Vector);
}
/**
Create a NET_BUF structure which contains Len byte data of
Nbuf starting from Offset. A new NET_BUF structure will be
created but the associated data in NET_VECTOR is shared.
This function exists to do IP packet fragmentation.
@param Nbuf Pointer to the net buffer to be cloned.
@param Offset Starting point of the data to be included in new
buffer.
@param Len How many data to include in new data
@param HeadSpace How many bytes of head space to reserve for
protocol header
@retval * Pointer to the cloned net buffer.
**/
NET_BUF *
NetbufGetFragment (
IN NET_BUF *Nbuf,
IN UINT32 Offset,
IN UINT32 Len,
IN UINT32 HeadSpace
)
{
NET_BUF *Child;
NET_VECTOR *Vector;
NET_BLOCK_OP *BlockOp;
UINT32 CurBlockOp;
UINT32 BlockOpNum;
UINT8 *FirstBulk;
UINT32 Index;
UINT32 First;
UINT32 Last;
UINT32 FirstSkip;
UINT32 FirstLen;
UINT32 LastLen;
UINT32 Cur;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
if ((Len == 0) || (Offset + Len > Nbuf->TotalSize)) {
return NULL;
}
//
// First find the first and last BlockOp that contains
// the valid data, and compute the offset of the first
// BlockOp and length of the last BlockOp
//
BlockOp = Nbuf->BlockOp;
Cur = 0;
for (Index = 0; Index < Nbuf->BlockOpNum; Index++) {
if (Offset < Cur + BlockOp[Index].Size) {
break;
}
Cur += BlockOp[Index].Size;
}
//
// First is the index of the first BlockOp, FirstSkip is
// the offset of the first byte in the first BlockOp.
//
First = Index;
FirstSkip = Offset - Cur;
FirstLen = BlockOp[Index].Size - FirstSkip;
//
//redundant assignment to make compiler happy.
//
Last = 0;
LastLen = 0;
if (Len > FirstLen) {
Cur += BlockOp[Index].Size;
Index++;
for (; Index < Nbuf->BlockOpNum; Index++) {
if (Offset + Len <= Cur + BlockOp[Index].Size) {
Last = Index;
LastLen = Offset + Len - Cur;
break;
}
Cur += BlockOp[Index].Size;
}
} else {
Last = First;
LastLen = Len;
FirstLen = Len;
}
BlockOpNum = Last - First + 1;
CurBlockOp = 0;
if (HeadSpace != 0) {
//
// Allocate an extra block to accomdate the head space.
//
BlockOpNum++;
Child = NetbufAllocStruct (1, BlockOpNum);
if (Child == NULL) {
return NULL;
}
FirstBulk = NetAllocatePool (HeadSpace);
if (FirstBulk == NULL) {
goto FreeChild;
}
Vector = Child->Vector;
Vector->Free = NetbufGetFragmentFree;
Vector->Arg = Nbuf->Vector;
Vector->Flag = NET_VECTOR_OWN_FIRST;
Vector->Len = HeadSpace;
//
//Reserve the head space in the first block
//
NetbufSetBlock (Child, FirstBulk, HeadSpace, 0);
Child->BlockOp[0].Head += HeadSpace;
Child->BlockOp[0].Size = 0;
CurBlockOp++;
}else {
Child = NetbufAllocStruct (0, BlockOpNum);
if (Child == NULL) {
return NULL;
}
Child->Vector = Nbuf->Vector;
}
NET_GET_REF (Nbuf->Vector);
Child->TotalSize = Len;
//
// Set all the BlockOp up, the first and last one are special
// and need special process.
//
NetbufSetBlockOp (
Child,
Nbuf->BlockOp[First].Head + FirstSkip,
FirstLen,
CurBlockOp++
);
for (Index = First + 1; Index <= Last - 1 ; Index++) {
NetbufSetBlockOp (
Child,
BlockOp[Index].Head,
BlockOp[Index].Size,
CurBlockOp++
);
}
if (First != Last) {
NetbufSetBlockOp (
Child,
BlockOp[Last].Head,
LastLen,
CurBlockOp
);
}
NetCopyMem (Child->ProtoData, Nbuf->ProtoData, NET_PROTO_DATA);
return Child;
FreeChild:
NetFreePool (Child);
return NULL;
}
/**
Build a NET_BUF from external blocks.
@param ExtFragment Pointer to the data block.
@param ExtNum The number of the data block.
@param HeadSpace The head space to be reserved.
@param HeadLen The length of the protocol header, This function
will pull that number of data into a linear block.
@param ExtFree Pointer to the caller provided free function.
@param Arg The argument passed to ExtFree when ExtFree is
called.
@retval * Pointer to the net buffer built from the data
blocks.
**/
NET_BUF *
NetbufFromExt (
IN NET_FRAGMENT *ExtFragment,
IN UINT32 ExtNum,
IN UINT32 HeadSpace,
IN UINT32 HeadLen,
IN NET_VECTOR_EXT_FREE ExtFree,
IN VOID *Arg OPTIONAL
)
{
NET_BUF *Nbuf;
NET_VECTOR *Vector;
NET_FRAGMENT SavedFragment;
UINT32 SavedIndex;
UINT32 TotalLen;
UINT32 BlockNum;
UINT8 *FirstBlock;
UINT32 FirstBlockLen;
UINT8 *Header;
UINT32 CurBlock;
UINT32 Index;
UINT32 Len;
UINT32 Copied;
ASSERT ((ExtFragment != NULL) && (ExtNum > 0) && (ExtFree != NULL));
SavedFragment.Bulk = NULL;
SavedFragment.Len = 0;
FirstBlockLen = 0;
FirstBlock = NULL;
BlockNum = ExtNum;
Index = 0;
TotalLen = 0;
SavedIndex = 0;
Len = 0;
Copied = 0;
//
// No need to consolidate the header if the first block is
// longer than the header length or there is only one block.
//
if ((ExtFragment[0].Len >= HeadLen) || (ExtNum == 1)) {
HeadLen = 0;
}
//
// Allocate an extra block if we need to:
// 1. Allocate some header space
// 2. aggreate the packet header
//
if ((HeadSpace != 0) || (HeadLen != 0)) {
FirstBlockLen = HeadLen + HeadSpace;
FirstBlock = NetAllocatePool (FirstBlockLen);
if (FirstBlock == NULL) {
return NULL;
}
BlockNum++;
}
//
// Copy the header to the first block, reduce the NET_BLOCK
// to allocate by one for each block that is completely covered
// by the first bulk.
//
if (HeadLen != 0) {
Len = HeadLen;
Header = FirstBlock + HeadSpace;
for (Index = 0; Index < ExtNum; Index++) {
if (Len >= ExtFragment[Index].Len) {
NetCopyMem (Header, ExtFragment[Index].Bulk, ExtFragment[Index].Len);
Copied += ExtFragment[Index].Len;
Len -= ExtFragment[Index].Len;
Header += ExtFragment[Index].Len;
TotalLen += ExtFragment[Index].Len;
BlockNum--;
if (Len == 0) {
//
// Increament the index number to point to the next
// non-empty fragment.
//
Index++;
break;
}
} else {
NetCopyMem (Header, ExtFragment[Index].Bulk, Len);
Copied += Len;
TotalLen += Len;
//
// Adjust the block structure to exclude the data copied,
// So, the left-over block can be processed as other blocks.
// But it must be recovered later. (SavedIndex > 0) always
// holds since we don't aggreate the header if the first block
// is bigger enough that the header is continuous
//
SavedIndex = Index;
SavedFragment = ExtFragment[Index];
ExtFragment[Index].Bulk += Len;
ExtFragment[Index].Len -= Len;
break;
}
}
}
Nbuf = NetbufAllocStruct (BlockNum, BlockNum);
if (Nbuf == NULL) {
goto FreeFirstBlock;
}
Vector = Nbuf->Vector;
Vector->Free = ExtFree;
Vector->Arg = Arg;
Vector->Flag = (FirstBlockLen ? NET_VECTOR_OWN_FIRST : 0);
//
// Set the first block up which may contain
// some head space and aggregated header
//
CurBlock = 0;
if (FirstBlockLen != 0) {
NetbufSetBlock (Nbuf, FirstBlock, HeadSpace + Copied, 0);
Nbuf->BlockOp[0].Head += HeadSpace;
Nbuf->BlockOp[0].Size = Copied;
CurBlock++;
}
for (; Index < ExtNum; Index++) {
NetbufSetBlock (Nbuf, ExtFragment[Index].Bulk, ExtFragment[Index].Len, CurBlock);
TotalLen += ExtFragment[Index].Len;
CurBlock++;
}
Vector->Len = TotalLen + HeadSpace;
Nbuf->TotalSize = TotalLen;
if (SavedIndex) {
ExtFragment[SavedIndex] = SavedFragment;
}
return Nbuf;
FreeFirstBlock:
NetFreePool (FirstBlock);
return NULL;
}
/**
Build a fragment table to contain the fragments in the
buffer. This is the opposite of the NetbufFromExt.
@param Nbuf Point to the net buffer
@param ExtFragment Pointer to the data block.
@param ExtNum The number of the data block.
@retval EFI_BUFFER_TOO_SMALL The number of non-empty block is bigger than ExtNum
@retval EFI_SUCCESS Fragment table built.
**/
EFI_STATUS
NetbufBuildExt (
IN NET_BUF *Nbuf,
IN NET_FRAGMENT *ExtFragment,
IN UINT32 *ExtNum
)
{
UINT32 Index;
UINT32 Current;
Current = 0;
for (Index = 0; (Index < Nbuf->BlockOpNum); Index++) {
if (Nbuf->BlockOp[Index].Size == 0) {
continue;
}
if (Current < *ExtNum) {
ExtFragment[Current].Bulk = Nbuf->BlockOp[Index].Head;
ExtFragment[Current].Len = Nbuf->BlockOp[Index].Size;
Current++;
} else {
return EFI_BUFFER_TOO_SMALL;
}
}
*ExtNum = Current;
return EFI_SUCCESS;
}
/**
Build a NET_BUF from a list of NET_BUF.
@param BufList A List of NET_BUF.
@param HeadSpace The head space to be reserved.
@param HeaderLen The length of the protocol header, This function
will pull that number of data into a linear block.
@param ExtFree Pointer to the caller provided free function.
@param Arg The argument passed to ExtFree when ExtFree is
called.
@retval * Pointer to the net buffer built from the data
blocks.
**/
NET_BUF *
NetbufFromBufList (
IN NET_LIST_ENTRY *BufList,
IN UINT32 HeadSpace,
IN UINT32 HeaderLen,
IN NET_VECTOR_EXT_FREE ExtFree,
IN VOID *Arg OPTIONAL
)
{
NET_FRAGMENT *Fragment;
UINT32 FragmentNum;
NET_LIST_ENTRY *Entry;
NET_BUF *Nbuf;
UINT32 Index;
UINT32 Current;
//
//Compute how many blocks are there
//
FragmentNum = 0;
NET_LIST_FOR_EACH (Entry, BufList) {
Nbuf = NET_LIST_USER_STRUCT (Entry, NET_BUF, List);
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
FragmentNum += Nbuf->BlockOpNum;
}
//
//Allocate and copy block points
//
Fragment = NetAllocatePool (sizeof (NET_FRAGMENT) * FragmentNum);
if (Fragment == NULL) {
return NULL;
}
Current = 0;
NET_LIST_FOR_EACH (Entry, BufList) {
Nbuf = NET_LIST_USER_STRUCT (Entry, NET_BUF, List);
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
for (Index = 0; Index < Nbuf->BlockOpNum; Index++) {
if (Nbuf->BlockOp[Index].Size) {
Fragment[Current].Bulk = Nbuf->BlockOp[Index].Head;
Fragment[Current].Len = Nbuf->BlockOp[Index].Size;
Current++;
}
}
}
Nbuf = NetbufFromExt (Fragment, Current, HeadSpace, HeaderLen, ExtFree, Arg);
NetFreePool (Fragment);
return Nbuf;
}
/**
Reserve some space in the header room of the buffer.
Upon allocation, all the space are in the tail room
of the buffer. Call this function to move some space
to the header room. This function is quite limited in
that it can only reserver space from the first block
of an empty NET_BUF not built from the external. But
it should be enough for the network stack.
@param Nbuf Pointer to the net buffer.
@param Len The length of buffer to be reserverd.
@return None.
**/
VOID
NetbufReserve (
IN NET_BUF *Nbuf,
IN UINT32 Len
)
{
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
NET_CHECK_SIGNATURE (Nbuf->Vector, NET_VECTOR_SIGNATURE);
ASSERT ((Nbuf->BlockOpNum == 1) && (Nbuf->TotalSize == 0));
ASSERT ((Nbuf->Vector->Free == NULL) && (Nbuf->Vector->Len >= Len));
Nbuf->BlockOp[0].Head += Len;
Nbuf->BlockOp[0].Tail += Len;
ASSERT (Nbuf->BlockOp[0].Tail <= Nbuf->BlockOp[0].BlockTail);
}
/**
Allocate some space from the header or tail of the buffer.
@param Nbuf Pointer to the net buffer.
@param Len The length of the buffer to be allocated.
@param FromHead The flag to indicate whether reserve the data from
head or tail. TRUE for from head, and FALSE for
from tail.
@retval * Pointer to the first byte of the allocated buffer.
**/
UINT8 *
NetbufAllocSpace (
IN NET_BUF *Nbuf,
IN UINT32 Len,
IN BOOLEAN FromHead
)
{
NET_BLOCK_OP *BlockOp;
UINT32 Index;
UINT8 *SavedTail;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
NET_CHECK_SIGNATURE (Nbuf->Vector, NET_VECTOR_SIGNATURE);
ASSERT (Len > 0);
if (FromHead) {
//
// Allocate some space from head. If the buffer is empty,
// allocate from the first block. If it isn't, allocate
// from the first non-empty block, or the block before that.
//
if (Nbuf->TotalSize == 0) {
Index = 0;
} else {
NetbufGetByte (Nbuf, 0, &Index);
if ((NET_HEADSPACE(&(Nbuf->BlockOp[Index])) < Len) && (Index > 0)) {
Index--;
}
}
BlockOp = &(Nbuf->BlockOp[Index]);
if (NET_HEADSPACE (BlockOp) < Len) {
return NULL;
}
BlockOp->Head -= Len;
BlockOp->Size += Len;
Nbuf->TotalSize += Len;
return BlockOp->Head;
} else {
//
// Allocate some space from the tail. If the buffer is empty,
// allocate from the first block. If it isn't, allocate
// from the last non-empty block, or the block after that.
//
if (Nbuf->TotalSize == 0) {
Index = 0;
} else {
NetbufGetByte (Nbuf, Nbuf->TotalSize - 1, &Index);
if ((NET_TAILSPACE(&(Nbuf->BlockOp[Index])) < Len) &&
(Index < Nbuf->BlockOpNum - 1)) {
Index++;
}
}
BlockOp = &(Nbuf->BlockOp[Index]);
if (NET_TAILSPACE (BlockOp) < Len) {
return NULL;
}
SavedTail = BlockOp->Tail;
BlockOp->Tail += Len;
BlockOp->Size += Len;
Nbuf->TotalSize += Len;
return SavedTail;
}
}
/**
Trim a single NET_BLOCK.
@param BlockOp Pointer to the NET_BLOCK.
@param Len The length of the data to be trimmed.
@param FromHead The flag to indicate whether trim data from head or
tail. TRUE for from head, and FALSE for from tail.
@return None.
**/
STATIC
VOID
NetblockTrim (
IN NET_BLOCK_OP *BlockOp,
IN UINT32 Len,
IN BOOLEAN FromHead
)
{
ASSERT (BlockOp && (BlockOp->Size >= Len));
BlockOp->Size -= Len;
if (FromHead) {
BlockOp->Head += Len;
} else {
BlockOp->Tail -= Len;
}
}
/**
Trim some data from the header or tail of the buffer.
@param Nbuf Pointer to the net buffer.
@param Len The length of the data to be trimmed.
@param FromHead The flag to indicate whether trim data from head or
tail. TRUE for from head, and FALSE for from tail.
@retval UINTN Length of the actually trimmed data.
**/
UINT32
NetbufTrim (
IN NET_BUF *Nbuf,
IN UINT32 Len,
IN BOOLEAN FromHead
)
{
NET_BLOCK_OP *BlockOp;
UINT32 Index;
UINT32 Trimmed;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
if (Len > Nbuf->TotalSize) {
Len = Nbuf->TotalSize;
}
//
// If FromTail is true, iterate backward. That
// is, init Index to NBuf->BlockNum - 1, and
// decrease it by 1 during each loop. Otherwise,
// iterate forward. That is, init Index to 0, and
// increase it by 1 during each loop.
//
Trimmed = 0;
Nbuf->TotalSize -= Len;
Index = (FromHead ? 0 : Nbuf->BlockOpNum - 1);
BlockOp = Nbuf->BlockOp;
for (;;) {
if (BlockOp[Index].Size == 0) {
Index += (FromHead ? 1 : -1);
continue;
}
if (Len > BlockOp[Index].Size) {
Len -= BlockOp[Index].Size;
Trimmed += BlockOp[Index].Size;
NetblockTrim (&BlockOp[Index], BlockOp[Index].Size, FromHead);
} else {
Trimmed += Len;
NetblockTrim (&BlockOp[Index], Len, FromHead);
break;
}
Index += (FromHead ? 1 : -1);
}
return Trimmed;
}
/**
Copy the data from the specific offset to the destination.
@param Nbuf Pointer to the net buffer.
@param Offset The sequence number of the first byte to copy.
@param Len Length of the data to copy.
@param Dest The destination of the data to copy to.
@retval UINTN The length of the copied data.
**/
UINT32
NetbufCopy (
IN NET_BUF *Nbuf,
IN UINT32 Offset,
IN UINT32 Len,
IN UINT8 *Dest
)
{
NET_BLOCK_OP *BlockOp;
UINT32 Skip;
UINT32 Left;
UINT32 Copied;
UINT32 Index;
UINT32 Cur;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
ASSERT (Dest);
if ((Len == 0) || (Nbuf->TotalSize <= Offset)) {
return 0;
}
if (Nbuf->TotalSize - Offset < Len) {
Len = Nbuf->TotalSize - Offset;
}
BlockOp = Nbuf->BlockOp;
//
// Skip to the offset. Don't make "Offset-By-One" error here.
// Cur + BLOCK.SIZE is the first sequence number of next block.
// So, (Offset < Cur + BLOCK.SIZE) means that the first byte
// is in the current block. if (Offset == Cur + BLOCK.SIZE), the
// first byte is the next block's first byte.
//
Cur = 0;
for (Index = 0; Index < Nbuf->BlockOpNum; Index++) {
if (BlockOp[Index].Size == 0) {
continue;
}
if (Offset < Cur + BlockOp[Index].Size) {
break;
}
Cur += BlockOp[Index].Size;
}
//
// Cur is the sequence number of the first byte in the block
// Offset - Cur is the number of bytes before first byte to
// to copy in the current block.
//
Skip = Offset - Cur;
Left = BlockOp[Index].Size - Skip;
if (Len <= Left) {
NetCopyMem (Dest, BlockOp[Index].Head + Skip, Len);
return Len;
}
NetCopyMem (Dest, BlockOp[Index].Head + Skip, Left);
Dest += Left;
Len -= Left;
Copied = Left;
Index++;
for (; Index < Nbuf->BlockOpNum; Index++) {
if (Len > BlockOp[Index].Size) {
Len -= BlockOp[Index].Size;
Copied += BlockOp[Index].Size;
NetCopyMem (Dest, BlockOp[Index].Head, BlockOp[Index].Size);
Dest += BlockOp[Index].Size;
} else {
Copied += Len;
NetCopyMem (Dest, BlockOp[Index].Head, Len);
break;
}
}
return Copied;
}
/**
Initiate the net buffer queue.
@param NbufQue Pointer to the net buffer queue to be initiated.
@return None.
**/
VOID
NetbufQueInit (
IN NET_BUF_QUEUE *NbufQue
)
{
NbufQue->Signature = NET_QUE_SIGNATURE;
NbufQue->RefCnt = 1;
NetListInit (&NbufQue->List);
NetListInit (&NbufQue->BufList);
NbufQue->BufSize = 0;
NbufQue->BufNum = 0;
}
/**
Allocate an initialized net buffer queue.
None.
@retval * Pointer to the allocated net buffer queue.
**/
NET_BUF_QUEUE *
NetbufQueAlloc (
VOID
)
{
NET_BUF_QUEUE *NbufQue;
NbufQue = NetAllocatePool (sizeof (NET_BUF_QUEUE));
if (NbufQue == NULL) {
return NULL;
}
NetbufQueInit (NbufQue);
return NbufQue;
}
/**
Free a net buffer queue.
@param NbufQue Poitner to the net buffer queue to be freed.
@return None.
**/
VOID
NetbufQueFree (
IN NET_BUF_QUEUE *NbufQue
)
{
NET_CHECK_SIGNATURE (NbufQue, NET_QUE_SIGNATURE);
NbufQue->RefCnt--;
if (NbufQue->RefCnt == 0) {
NetbufQueFlush (NbufQue);
NetFreePool (NbufQue);
}
}
/**
Append a buffer to the end of the queue.
@param NbufQue Pointer to the net buffer queue.
@param Nbuf Pointer to the net buffer to be appended.
@return None.
**/
VOID
NetbufQueAppend (
IN NET_BUF_QUEUE *NbufQue,
IN NET_BUF *Nbuf
)
{
NET_CHECK_SIGNATURE (NbufQue, NET_QUE_SIGNATURE);
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
NetListInsertTail (&NbufQue->BufList, &Nbuf->List);
NbufQue->BufSize += Nbuf->TotalSize;
NbufQue->BufNum++;
}
/**
Remove a net buffer from head in the specific queue.
@param NbufQue Pointer to the net buffer queue.
@retval * Pointer to the net buffer removed from the specific
queue.
**/
NET_BUF *
NetbufQueRemove (
IN NET_BUF_QUEUE *NbufQue
)
{
NET_BUF *First;
NET_CHECK_SIGNATURE (NbufQue, NET_QUE_SIGNATURE);
if (NbufQue->BufNum == 0) {
return NULL;
}
First = NET_LIST_USER_STRUCT (NbufQue->BufList.ForwardLink, NET_BUF, List);
NetListRemoveHead (&NbufQue->BufList);
NbufQue->BufSize -= First->TotalSize;
NbufQue->BufNum--;
return First;
}
/**
Copy some data from the buffer queue to the destination.
@param NbufQue Pointer to the net buffer queue.
@param Offset The sequence number of the first byte to copy.
@param Len Length of the data to copy.
@param Dest The destination of the data to copy to.
@retval UINTN The length of the copied data.
**/
UINT32
NetbufQueCopy (
IN NET_BUF_QUEUE *NbufQue,
IN UINT32 Offset,
IN UINT32 Len,
IN UINT8 *Dest
)
{
NET_LIST_ENTRY *Entry;
NET_BUF *Nbuf;
UINT32 Skip;
UINT32 Left;
UINT32 Cur;
UINT32 Copied;
NET_CHECK_SIGNATURE (NbufQue, NET_QUE_SIGNATURE);
ASSERT (Dest != NULL);
if ((Len == 0) || (NbufQue->BufSize <= Offset)) {
return 0;
}
if (NbufQue->BufSize - Offset < Len) {
Len = NbufQue->BufSize - Offset;
}
//
// skip to the Offset
//
Cur = 0;
Nbuf = NULL;
NET_LIST_FOR_EACH (Entry, &NbufQue->BufList) {
Nbuf = NET_LIST_USER_STRUCT (Entry, NET_BUF, List);
if (Offset < Cur + Nbuf->TotalSize) {
break;
}
Cur += Nbuf->TotalSize;
}
//
// Copy the data in the first buffer.
//
Skip = Offset - Cur;
Left = Nbuf->TotalSize - Skip;
if (Len < Left) {
return NetbufCopy (Nbuf, Skip, Len, Dest);
}
NetbufCopy (Nbuf, Skip, Left, Dest);
Dest += Left;
Len -= Left;
Copied = Left;
//
// Iterate over the others
//
Entry = Entry->ForwardLink;
while ((Len > 0) && (Entry != &NbufQue->BufList)) {
Nbuf = NET_LIST_USER_STRUCT (Entry, NET_BUF, List);
if (Len > Nbuf->TotalSize) {
Len -= Nbuf->TotalSize;
Copied += Nbuf->TotalSize;
NetbufCopy (Nbuf, 0, Nbuf->TotalSize, Dest);
Dest += Nbuf->TotalSize;
} else {
NetbufCopy (Nbuf, 0, Len, Dest);
Copied += Len;
break;
}
Entry = Entry->ForwardLink;
}
return Copied;
}
/**
Trim some data from the queue header, release the buffer if
whole buffer is trimmed.
@param NbufQue Pointer to the net buffer queue.
@param Len Length of the data to trim.
@retval UINTN The length of the data trimmed.
**/
UINT32
NetbufQueTrim (
IN NET_BUF_QUEUE *NbufQue,
IN UINT32 Len
)
{
NET_LIST_ENTRY *Entry;
NET_LIST_ENTRY *Next;
NET_BUF *Nbuf;
UINT32 Trimmed;
NET_CHECK_SIGNATURE (NbufQue, NET_QUE_SIGNATURE);
if (Len == 0) {
return 0;
}
if (Len > NbufQue->BufSize) {
Len = NbufQue->BufSize;
}
NbufQue->BufSize -= Len;
Trimmed = 0;
NET_LIST_FOR_EACH_SAFE (Entry, Next, &NbufQue->BufList) {
Nbuf = NET_LIST_USER_STRUCT (Entry, NET_BUF, List);
if (Len >= Nbuf->TotalSize) {
Trimmed += Nbuf->TotalSize;
Len -= Nbuf->TotalSize;
NetListRemoveEntry (Entry);
NetbufFree (Nbuf);
NbufQue->BufNum--;
if (Len == 0) {
break;
}
} else {
Trimmed += NetbufTrim (Nbuf, Len, NET_BUF_HEAD);
break;
}
}
return Trimmed;
}
/**
Flush the net buffer queue.
@param NbufQue Pointer to the queue to be flushed.
@return None.
**/
VOID
NetbufQueFlush (
IN NET_BUF_QUEUE *NbufQue
)
{
NET_CHECK_SIGNATURE (NbufQue, NET_QUE_SIGNATURE);
NetbufFreeList (&NbufQue->BufList);
NbufQue->BufNum = 0;
NbufQue->BufSize = 0;
}
/**
Compute checksum for a bulk of data.
@param Bulk Pointer to the data.
@param Len Length of the data, in bytes.
@retval UINT16 The computed checksum.
**/
UINT16
NetblockChecksum (
IN UINT8 *Bulk,
IN UINT32 Len
)
{
register UINT32 Sum;
Sum = 0;
while (Len > 1) {
Sum += *(UINT16 *) Bulk;
Bulk += 2;
Len -= 2;
}
//
// Add left-over byte, if any
//
if (Len > 0) {
Sum += *(UINT8 *) Bulk;
}
//
// Fold 32-bit sum to 16 bits
//
while (Sum >> 16) {
Sum = (Sum & 0xffff) + (Sum >> 16);
}
return (UINT16) Sum;
}
/**
Add two checksums.
@param Checksum1 The first checksum to be added.
@param Checksum2 The second checksum to be added.
@retval UINT16 The new checksum.
**/
UINT16
NetAddChecksum (
IN UINT16 Checksum1,
IN UINT16 Checksum2
)
{
UINT32 Sum;
Sum = Checksum1 + Checksum2;
//
// two UINT16 can only add up to a carry of 1.
//
if (Sum >> 16) {
Sum = (Sum & 0xffff) + 1;
}
return (UINT16) Sum;
}
/**
Compute the checksum for a NET_BUF.
@param Nbuf Pointer to the net buffer.
@retval UINT16 The computed checksum.
**/
UINT16
NetbufChecksum (
IN NET_BUF *Nbuf
)
{
NET_BLOCK_OP *BlockOp;
UINT32 Offset;
UINT16 TotalSum;
UINT16 BlockSum;
UINT32 Index;
NET_CHECK_SIGNATURE (Nbuf, NET_BUF_SIGNATURE);
TotalSum = 0;
Offset = 0;
BlockOp = Nbuf->BlockOp;
for (Index = 0; Index < Nbuf->BlockOpNum; Index++) {
if (BlockOp[Index].Size == 0) {
continue;
}
BlockSum = NetblockChecksum (BlockOp[Index].Head, BlockOp[Index].Size);
if (Offset & 0x01) {
//
// The checksum starts with an odd byte, swap
// the checksum before added to total checksum
//
BlockSum = (UINT16) NET_SWAP_SHORT (BlockSum);
}
TotalSum = NetAddChecksum (BlockSum, TotalSum);
Offset += BlockOp[Index].Size;
}
return TotalSum;
}
/**
Compute the checksum for TCP/UDP pseudo header.
Src, Dst are in network byte order. and Len is
in host byte order.
@param Src The source address of the packet.
@param Dst The destination address of the packet.
@param Proto The protocol type of the packet.
@param Len The length of the packet.
@retval UINT16 The computed checksum.
**/
UINT16
NetPseudoHeadChecksum (
IN IP4_ADDR Src,
IN IP4_ADDR Dst,
IN UINT8 Proto,
IN UINT16 Len
)
{
NET_PSEUDO_HDR Hdr;
//
// Zero the memory to relieve align problems
//
NetZeroMem (&Hdr, sizeof (Hdr));
Hdr.SrcIp = Src;
Hdr.DstIp = Dst;
Hdr.Protocol = Proto;
Hdr.Len = HTONS (Len);
return NetblockChecksum ((UINT8 *) &Hdr, sizeof (Hdr));
}