blob: 8c6e368e7a66cf4b0f80eda77fe0f107952f0041 [file] [log] [blame]
/*
* internal HTTP message
*
* Copyright 2018 HAProxy Technologies, Christopher Faulet <cfaulet@haproxy.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <haproxy/chunk.h>
#include <haproxy/htx.h>
struct htx htx_empty = { .size = 0, .data = 0, .head = -1, .tail = -1, .first = -1 };
/* Defragments an HTX message. It removes unused blocks and unwraps the payloads
* part. A temporary buffer is used to do so. This function never fails. Most of
* time, we need keep a ref on a specific HTX block. Thus is <blk> is set, the
* pointer on its new position, after defrag, is returned. In addition, if the
* size of the block must be altered, <blkinfo> info must be provided (!=
* 0). But in this case, it remains the caller responsibility to update the
* block content.
*/
/* TODO: merge data blocks into one */
struct htx_blk *htx_defrag(struct htx *htx, struct htx_blk *blk, uint32_t blkinfo)
{
struct buffer *chunk = get_trash_chunk();
struct htx *tmp = htxbuf(chunk);
struct htx_blk *newblk, *oldblk;
uint32_t new, old, blkpos;
uint32_t addr, blksz;
int32_t first = -1;
if (htx->head == -1)
return NULL;
blkpos = -1;
new = 0;
addr = 0;
tmp->size = htx->size;
tmp->data = 0;
/* start from the head */
for (old = htx_get_head(htx); old != -1; old = htx_get_next(htx, old)) {
oldblk = htx_get_blk(htx, old);
if (htx_get_blk_type(oldblk) == HTX_BLK_UNUSED)
continue;
blksz = htx_get_blksz(oldblk);
memcpy((void *)tmp->blocks + addr, htx_get_blk_ptr(htx, oldblk), blksz);
/* update the start-line position */
if (htx->first == old)
first = new;
newblk = htx_get_blk(tmp, new);
newblk->addr = addr;
newblk->info = oldblk->info;
/* if <blk> is defined, save its new position */
if (blk != NULL && blk == oldblk) {
if (blkinfo)
newblk->info = blkinfo;
blkpos = new;
}
blksz = htx_get_blksz(newblk);
addr += blksz;
tmp->data += blksz;
new++;
}
htx->data = tmp->data;
htx->first = first;
htx->head = 0;
htx->tail = new - 1;
htx->head_addr = htx->end_addr = 0;
htx->tail_addr = addr;
htx->flags &= ~HTX_FL_FRAGMENTED;
memcpy((void *)htx->blocks, (void *)tmp->blocks, htx->size);
return ((blkpos == -1) ? NULL : htx_get_blk(htx, blkpos));
}
/* Degragments HTX blocks of an HTX message. Payloads part is keep untouched
* here. This function will move back all blocks starting at the position 0,
* removing unused blocks. It must never be called with an empty message.
*/
static void htx_defrag_blks(struct htx *htx)
{
int32_t pos, new;
new = 0;
for (pos = htx_get_head(htx); pos != -1; pos = htx_get_next(htx, pos)) {
struct htx_blk *posblk, *newblk;
if (pos == new) {
new++;
continue;
}
posblk = htx_get_blk(htx, pos);
if (htx_get_blk_type(posblk) == HTX_BLK_UNUSED)
continue;
if (htx->first == pos)
htx->first = new;
newblk = htx_get_blk(htx, new++);
newblk->info = posblk->info;
newblk->addr = posblk->addr;
}
BUG_ON(!new);
htx->head = 0;
htx->tail = new - 1;
}
/* Reserves a new block in the HTX message <htx> with a content of <blksz>
* bytes. If there is not enough space, NULL is returned. Otherwise the reserved
* block is returned and the HTX message is updated. Space for this new block is
* reserved in the HTX message. But it is the caller responsibility to set right
* info in the block to reflect the stored data.
*/
static struct htx_blk *htx_reserve_nxblk(struct htx *htx, uint32_t blksz)
{
struct htx_blk *blk;
uint32_t tail, headroom, tailroom;
if (blksz > htx_free_data_space(htx))
return NULL; /* full */
if (htx->head == -1) {
/* Empty message */
htx->head = htx->tail = htx->first = 0;
blk = htx_get_blk(htx, htx->tail);
blk->addr = 0;
htx->data = blksz;
htx->tail_addr = blksz;
return blk;
}
/* Find the block's position. First, we try to get the next position in
* the message, increasing the tail by one. If this position is not
* available with some holes, we try to defrag the blocks without
* touching their paylood. If it is impossible, we fully defrag the
* message.
*/
tail = htx->tail + 1;
if (htx_pos_to_addr(htx, tail) >= htx->tail_addr)
;
else if (htx->head > 0) {
htx_defrag_blks(htx);
tail = htx->tail + 1;
BUG_ON(htx_pos_to_addr(htx, tail) < htx->tail_addr);
}
else
goto defrag;
/* Now, we have found the block's position. Try to find where to put its
* payload. The free space is split in two areas:
*
* * The free space in front of the blocks table. This one is used if and
* only if the other one was not used yet.
*
* * The free space at the beginning of the message. Once this one is
* used, the other one is never used again, until the next defrag.
*/
headroom = (htx->end_addr - htx->head_addr);
tailroom = (!htx->head_addr ? htx_pos_to_addr(htx, tail) - htx->tail_addr : 0);
BUG_ON((int32_t)headroom < 0);
BUG_ON((int32_t)tailroom < 0);
if (blksz <= tailroom) {
blk = htx_get_blk(htx, tail);
blk->addr = htx->tail_addr;
htx->tail_addr += blksz;
}
else if (blksz <= headroom) {
blk = htx_get_blk(htx, tail);
blk->addr = htx->head_addr;
htx->head_addr += blksz;
}
else {
defrag:
/* need to defragment the message before inserting upfront */
htx_defrag(htx, NULL, 0);
tail = htx->tail + 1;
blk = htx_get_blk(htx, tail);
blk->addr = htx->tail_addr;
htx->tail_addr += blksz;
}
htx->tail = tail;
htx->data += blksz;
/* Set first position if not already set */
if (htx->first == -1)
htx->first = tail;
BUG_ON((int32_t)htx->tail_addr < 0);
BUG_ON((int32_t)htx->head_addr < 0);
BUG_ON(htx->end_addr > htx->tail_addr);
BUG_ON(htx->head_addr > htx->end_addr);
return blk;
}
/* Prepares the block to an expansion of its payload. The payload will be
* expanded by <delta> bytes and we need find where this expansion will be
* performed. It can be a compression if <delta> is negative. This function only
* updates all addresses. The caller have the responsibility to perform the
* expansion and update the block and the HTX message accordingly. No error must
* occur. It returns following values:
*
* 0: The expansion cannot be performed, there is not enough space.
*
* 1: the expansion must be performed in place, there is enough space after
* the block's payload to handle it. This is especially true if it is a
* compression and not an expension.
*
* 2: the block's payload must be moved at the new block address before doing
* the expansion.
*
* 3: the HTX message message must be defragmented
*/
static int htx_prepare_blk_expansion(struct htx *htx, struct htx_blk *blk, int32_t delta)
{
uint32_t sz, tailroom, headroom;
int ret = 3;
BUG_ON(htx->head == -1);
headroom = (htx->end_addr - htx->head_addr);
tailroom = (htx_pos_to_addr(htx, htx->tail) - htx->tail_addr);
BUG_ON((int32_t)headroom < 0);
BUG_ON((int32_t)tailroom < 0);
sz = htx_get_blksz(blk);
if (delta <= 0) {
/* It is a compression, it can be performed in place */
if (blk->addr+sz == htx->tail_addr)
htx->tail_addr += delta;
else if (blk->addr+sz == htx->head_addr)
htx->head_addr += delta;
ret = 1;
}
else if (delta > htx_free_space(htx)) {
/* There is not enough space to handle the expansion */
ret = 0;
}
else if (blk->addr+sz == htx->tail_addr) {
/* The block's payload is just before the tail room */
if (delta < tailroom) {
/* Expand the block's payload */
htx->tail_addr += delta;
ret = 1;
}
else if ((sz + delta) < headroom) {
uint32_t oldaddr = blk->addr;
/* Move the block's payload into the headroom */
blk->addr = htx->head_addr;
htx->tail_addr -= sz;
htx->head_addr += sz + delta;
if (oldaddr == htx->end_addr) {
if (htx->end_addr == htx->tail_addr) {
htx->tail_addr = htx->head_addr;
htx->head_addr = htx->end_addr = 0;
}
else
htx->end_addr += sz;
}
ret = 2;
}
}
else if (blk->addr+sz == htx->head_addr) {
/* The block's payload is just before the head room */
if (delta < headroom) {
/* Expand the block's payload */
htx->head_addr += delta;
ret = 1;
}
}
else {
/* The block's payload is not at the rooms edge */
if (!htx->head_addr && sz+delta < tailroom) {
/* Move the block's payload into the tailroom */
if (blk->addr == htx->end_addr)
htx->end_addr += sz;
blk->addr = htx->tail_addr;
htx->tail_addr += sz + delta;
ret = 2;
}
else if (sz+delta < headroom) {
/* Move the block's payload into the headroom */
if (blk->addr == htx->end_addr)
htx->end_addr += sz;
blk->addr = htx->head_addr;
htx->head_addr += sz + delta;
ret = 2;
}
}
/* Otherwise defrag the HTX message */
BUG_ON((int32_t)htx->tail_addr < 0);
BUG_ON((int32_t)htx->head_addr < 0);
BUG_ON(htx->end_addr > htx->tail_addr);
BUG_ON(htx->head_addr > htx->end_addr);
return ret;
}
/* Adds a new block of type <type> in the HTX message <htx>. Its content size is
* passed but it is the caller responsibility to do the copy.
*/
struct htx_blk *htx_add_blk(struct htx *htx, enum htx_blk_type type, uint32_t blksz)
{
struct htx_blk *blk;
BUG_ON(blksz >= 256 << 20);
blk = htx_reserve_nxblk(htx, blksz);
if (!blk)
return NULL;
BUG_ON(blk->addr > htx->size);
blk->info = (type << 28);
return blk;
}
/* Removes the block <blk> from the HTX message <htx>. The function returns the
* block following <blk> or NULL if <blk> is the last block or the last inserted
* one.
*/
struct htx_blk *htx_remove_blk(struct htx *htx, struct htx_blk *blk)
{
enum htx_blk_type type;
uint32_t pos, addr, sz;
BUG_ON(htx->head == -1);
/* This is the last block in use */
if (htx->head == htx->tail) {
uint32_t flags = (htx->flags & ~HTX_FL_FRAGMENTED); /* Preserve flags except FRAGMENTED */
htx_reset(htx);
htx->flags = flags; /* restore flags */
return NULL;
}
type = htx_get_blk_type(blk);
pos = htx_get_blk_pos(htx, blk);
sz = htx_get_blksz(blk);
addr = blk->addr;
if (type != HTX_BLK_UNUSED) {
/* Mark the block as unused, decrement allocated size */
htx->data -= htx_get_blksz(blk);
blk->info = ((uint32_t)HTX_BLK_UNUSED << 28);
}
/* There is at least 2 blocks, so tail is always > 0 */
if (pos == htx->head) {
/* move the head forward */
htx->head++;
}
else if (pos == htx->tail) {
/* remove the tail. this was the last inserted block so
* return NULL. */
htx->tail--;
blk = NULL;
goto end;
}
else
htx->flags |= HTX_FL_FRAGMENTED;
blk = htx_get_blk(htx, pos+1);
end:
if (pos == htx->first)
htx->first = (blk ? htx_get_blk_pos(htx, blk) : -1);
if (htx->head == htx->tail) {
/* If there is just one block in the HTX message, free space can
* be adjusted. This operation could save some defrags. */
struct htx_blk *lastblk = htx_get_blk(htx, htx->tail);
htx->head_addr = 0;
htx->end_addr = lastblk->addr;
htx->tail_addr = lastblk->addr+htx->data;
}
else {
if (addr+sz == htx->tail_addr)
htx->tail_addr = addr;
else if (addr+sz == htx->head_addr)
htx->head_addr = addr;
if (addr == htx->end_addr) {
if (htx->tail_addr == htx->end_addr) {
htx->tail_addr = htx->head_addr;
htx->head_addr = htx->end_addr = 0;
}
else
htx->end_addr += sz;
}
}
BUG_ON((int32_t)htx->tail_addr < 0);
BUG_ON((int32_t)htx->head_addr < 0);
BUG_ON(htx->end_addr > htx->tail_addr);
BUG_ON(htx->head_addr > htx->end_addr);
return blk;
}
/* Looks for the HTX block containing the offset <offset>, starting at the HTX
* message's head. The function returns an htx_ret with the found HTX block and
* the position inside this block where the offset is. If the offset <offset> is
* outside of the HTX message, htx_ret.blk is set to NULL.
*/
struct htx_ret htx_find_offset(struct htx *htx, uint32_t offset)
{
struct htx_blk *blk;
struct htx_ret htxret = { .blk = NULL, .ret = 0 };
if (offset >= htx->data)
return htxret;
for (blk = htx_get_head_blk(htx); blk && offset; blk = htx_get_next_blk(htx, blk)) {
uint32_t sz = htx_get_blksz(blk);
if (offset < sz)
break;
offset -= sz;
}
htxret.blk = blk;
htxret.ret = offset;
return htxret;
}
/* Removes all blocks after the one containing the offset <offset>. This last
* one may be truncated if it is a DATA block.
*/
void htx_truncate(struct htx *htx, uint32_t offset)
{
struct htx_blk *blk;
struct htx_ret htxret = htx_find_offset(htx, offset);
blk = htxret.blk;
if (blk && htxret.ret && htx_get_blk_type(blk) == HTX_BLK_DATA) {
htx_change_blk_value_len(htx, blk, htxret.ret);
blk = htx_get_next_blk(htx, blk);
}
while (blk)
blk = htx_remove_blk(htx, blk);
}
/* Drains <count> bytes from the HTX message <htx>. If the last block is a DATA
* block, it will be cut if necessary. Others blocks will be removed at once if
* <count> is large enough. The function returns an htx_ret with the first block
* remaining in the message and the amount of data drained. If everything is
* removed, htx_ret.blk is set to NULL.
*/
struct htx_ret htx_drain(struct htx *htx, uint32_t count)
{
struct htx_blk *blk;
struct htx_ret htxret = { .blk = NULL, .ret = 0 };
if (count == htx->data) {
uint32_t flags = (htx->flags & ~HTX_FL_FRAGMENTED); /* Preserve flags except FRAGMENTED */
htx_reset(htx);
htx->flags = flags; /* restore flags */
htxret.ret = count;
return htxret;
}
blk = htx_get_head_blk(htx);
while (count && blk) {
uint32_t sz = htx_get_blksz(blk);
enum htx_blk_type type = htx_get_blk_type(blk);
/* Ignore unused block */
if (type == HTX_BLK_UNUSED)
goto next;
if (sz > count) {
if (type == HTX_BLK_DATA) {
htx_cut_data_blk(htx, blk, count);
htxret.ret += count;
}
break;
}
count -= sz;
htxret.ret += sz;
next:
blk = htx_remove_blk(htx, blk);
}
htxret.blk = blk;
return htxret;
}
/* Tries to append data to the last inserted block, if the type matches and if
* there is enough space to take it all. If the space wraps, the buffer is
* defragmented and a new block is inserted. If an error occurred, NULL is
* returned. Otherwise, on success, the updated block (or the new one) is
* returned. Due to its nature this function can be expensive and should be
* avoided whenever possible.
*/
struct htx_blk *htx_add_data_atonce(struct htx *htx, struct ist data)
{
struct htx_blk *blk, *tailblk;
void *ptr;
uint32_t len, sz, tailroom, headroom;
if (htx->head == -1)
goto add_new_block;
/* Not enough space to store data */
if (data.len > htx_free_data_space(htx))
return NULL;
/* get the tail block and its size */
tailblk = htx_get_tail_blk(htx);
if (tailblk == NULL)
goto add_new_block;
sz = htx_get_blksz(tailblk);
/* Don't try to append data if the last inserted block is not of the
* same type */
if (htx_get_blk_type(tailblk) != HTX_BLK_DATA)
goto add_new_block;
/*
* Same type and enough space: append data
*/
headroom = (htx->end_addr - htx->head_addr);
tailroom = (htx_pos_to_addr(htx, htx->tail) - htx->tail_addr);
BUG_ON((int32_t)headroom < 0);
BUG_ON((int32_t)tailroom < 0);
len = data.len;
if (tailblk->addr+sz == htx->tail_addr) {
if (data.len <= tailroom)
goto append_data;
else if (!htx->head_addr) {
len = tailroom;
goto append_data;
}
}
else if (tailblk->addr+sz == htx->head_addr && data.len <= headroom)
goto append_data;
goto add_new_block;
append_data:
/* Append data and update the block itself */
ptr = htx_get_blk_ptr(htx, tailblk);
memcpy(ptr+sz, data.ptr, len);
htx_change_blk_value_len(htx, tailblk, sz+len);
if (data.len == len) {
blk = tailblk;
goto end;
}
data = istadv(data, len);
add_new_block:
blk = htx_add_blk(htx, HTX_BLK_DATA, data.len);
if (!blk)
return NULL;
blk->info += data.len;
memcpy(htx_get_blk_ptr(htx, blk), data.ptr, data.len);
end:
BUG_ON((int32_t)htx->tail_addr < 0);
BUG_ON((int32_t)htx->head_addr < 0);
BUG_ON(htx->end_addr > htx->tail_addr);
BUG_ON(htx->head_addr > htx->end_addr);
return blk;
}
/* Replaces a value part of a block by a new one. The new part can be smaller or
* larger than the old one. This function works for any kind of block with
* attached data. It returns the new block on success, otherwise it returns
* NULL.
*/
struct htx_blk *htx_replace_blk_value(struct htx *htx, struct htx_blk *blk,
const struct ist old, const struct ist new)
{
struct ist n, v;
int32_t delta;
int ret;
n = htx_get_blk_name(htx, blk);
v = htx_get_blk_value(htx, blk);
delta = new.len - old.len;
ret = htx_prepare_blk_expansion(htx, blk, delta);
if (!ret)
return NULL; /* not enough space */
if (ret == 1) { /* Replace in place */
if (delta <= 0) {
/* compression: copy new data first then move the end */
memcpy(old.ptr, new.ptr, new.len);
memmove(old.ptr + new.len, old.ptr + old.len, (v.ptr + v.len) - (old.ptr + old.len));
}
else {
/* expansion: move the end first then copy new data */
memmove(old.ptr + new.len, old.ptr + old.len, (v.ptr + v.len) - (old.ptr + old.len));
memcpy(old.ptr, new.ptr, new.len);
}
/* set the new block size and update HTX message */
htx_set_blk_value_len(blk, v.len + delta);
htx->data += delta;
}
else if (ret == 2) { /* New address but no defrag */
void *ptr = htx_get_blk_ptr(htx, blk);
/* Copy the name, if any */
memcpy(ptr, n.ptr, n.len);
ptr += n.len;
/* Copy value before old part, if any */
memcpy(ptr, v.ptr, old.ptr - v.ptr);
ptr += old.ptr - v.ptr;
/* Copy new value */
memcpy(ptr, new.ptr, new.len);
ptr += new.len;
/* Copy value after old part, if any */
memcpy(ptr, old.ptr + old.len, (v.ptr + v.len) - (old.ptr + old.len));
/* set the new block size and update HTX message */
htx_set_blk_value_len(blk, v.len + delta);
htx->data += delta;
}
else { /* Do a degrag first (it is always an expansion) */
struct htx_blk tmpblk;
int32_t offset;
/* use tmpblk to set new block size before defrag and to compute
* the offset after defrag
*/
tmpblk.addr = blk->addr;
tmpblk.info = blk->info;
htx_set_blk_value_len(&tmpblk, v.len + delta);
/* htx_defrag() will take care to update the block size and the htx message */
blk = htx_defrag(htx, blk, tmpblk.info);
/* newblk is now the new HTX block. Compute the offset to copy/move payload */
offset = blk->addr - tmpblk.addr;
/* move the end first and copy new data
*/
memmove(old.ptr + offset + new.len, old.ptr + offset + old.len, (v.ptr + v.len) - (old.ptr + old.len));
memcpy(old.ptr + offset, new.ptr, new.len);
}
return blk;
}
/* Transfer HTX blocks from <src> to <dst>, stopping on the first block of the
* type <mark> (typically EOH or EOT) or when <count> bytes were moved
* (including payload and meta-data). It returns the number of bytes moved and
* the last HTX block inserted in <dst>.
*/
struct htx_ret htx_xfer_blks(struct htx *dst, struct htx *src, uint32_t count,
enum htx_blk_type mark)
{
struct htx_blk *blk, *dstblk;
struct htx_blk *srcref, *dstref;
enum htx_blk_type type;
uint32_t info, max, sz, ret;
ret = htx_used_space(dst);
srcref = dstref = dstblk = NULL;
/* blocks are not removed yet from <src> HTX message to be able to
* rollback the transfer if all the headers/trailers are not copied.
*/
for (blk = htx_get_head_blk(src); blk && count; blk = htx_get_next_blk(src, blk)) {
type = htx_get_blk_type(blk);
/* Ignore unused block */
if (type == HTX_BLK_UNUSED)
continue;
max = htx_get_max_blksz(dst, count);
if (!max)
break;
sz = htx_get_blksz(blk);
info = blk->info;
if (sz > max) {
/* Only DATA blocks can be partially xferred */
if (type != HTX_BLK_DATA)
break;
sz = max;
info = (type << 28) + sz;
}
dstblk = htx_reserve_nxblk(dst, sz);
if (!dstblk)
break;
dstblk->info = info;
memcpy(htx_get_blk_ptr(dst, dstblk), htx_get_blk_ptr(src, blk), sz);
count -= sizeof(dstblk) + sz;
if (blk->info != info) {
/* Partial xfer: don't remove <blk> from <src> but
* resize its content */
htx_cut_data_blk(src, blk, sz);
break;
}
if (type == mark) {
blk = htx_get_next_blk(src, blk);
srcref = dstref = NULL;
break;
}
/* Save <blk> to <srcref> and <dstblk> to <dstref> when we start
* to xfer headers or trailers. When EOH/EOT block is reached,
* both are reset. It is mandatory to be able to rollback a
* partial transfer.
*/
if (!srcref && !dstref &&
(type == HTX_BLK_REQ_SL || type == HTX_BLK_RES_SL || type == HTX_BLK_TLR)) {
srcref = blk;
dstref = dstblk;
}
else if (type == HTX_BLK_EOH || type == HTX_BLK_EOT)
srcref = dstref = NULL;
}
if (unlikely(dstref)) {
/* Headers or trailers part was partially xferred, so rollback the copy
* by removing all block between <dstref> and <dstblk>, both included.
*/
while (dstref && dstref != dstblk)
dstref = htx_remove_blk(dst, dstref);
htx_remove_blk(dst, dstblk);
/* <dst> HTX message is empty, it means the headers or trailers
* part is too big to be copied at once.
*/
if (htx_is_empty(dst))
src->flags |= HTX_FL_PARSING_ERROR;
}
/* Now, remove xferred blocks from <src> htx message */
if (!blk && !srcref) {
/* End of src reached, all blocks were consumed, drain all data */
htx_drain(src, src->data);
}
else {
/* Remove all block from the head to <blk>, or <srcref> if defined, excluded */
srcref = (srcref ? srcref : blk);
for (blk = htx_get_head_blk(src); blk && blk != srcref; blk = htx_remove_blk(src, blk));
}
end:
ret = htx_used_space(dst) - ret;
return (struct htx_ret){.ret = ret, .blk = dstblk};
}
/* Replaces an header by a new one. The new header can be smaller or larger than
* the old one. It returns the new block on success, otherwise it returns NULL.
* The header name is always lower cased.
*/
struct htx_blk *htx_replace_header(struct htx *htx, struct htx_blk *blk,
const struct ist name, const struct ist value)
{
enum htx_blk_type type;
void *ptr;
int32_t delta;
int ret;
type = htx_get_blk_type(blk);
if (type != HTX_BLK_HDR)
return NULL;
delta = name.len + value.len - htx_get_blksz(blk);
ret = htx_prepare_blk_expansion(htx, blk, delta);
if (!ret)
return NULL; /* not enough space */
/* Replace in place or at a new address is the same. We replace all the
* header (name+value). Only take care to defrag the message if
* necessary. */
if (ret == 3)
blk = htx_defrag(htx, blk, (type << 28) + (value.len << 8) + name.len);
else {
/* Set the new block size and update HTX message */
blk->info = (type << 28) + (value.len << 8) + name.len;
htx->data += delta;
}
/* Finally, copy data. */
ptr = htx_get_blk_ptr(htx, blk);
ist2bin_lc(ptr, name);
memcpy(ptr + name.len, value.ptr, value.len);
return blk;
}
/* Replaces the parts of the start-line. It returns the new start-line on
* success, otherwise it returns NULL. It is the caller responsibility to update
* sl->info, if necessary.
*/
struct htx_sl *htx_replace_stline(struct htx *htx, struct htx_blk *blk, const struct ist p1,
const struct ist p2, const struct ist p3)
{
enum htx_blk_type type;
struct htx_sl *sl;
struct htx_sl tmp; /* used to save sl->info and sl->flags */
uint32_t sz;
int32_t delta;
int ret;
type = htx_get_blk_type(blk);
if (type != HTX_BLK_REQ_SL && type != HTX_BLK_RES_SL)
return NULL;
/* Save start-line info and flags */
sl = htx_get_blk_ptr(htx, blk);
tmp.info = sl->info;
tmp.flags = sl->flags;
sz = htx_get_blksz(blk);
delta = sizeof(*sl) + p1.len + p2.len + p3.len - sz;
ret = htx_prepare_blk_expansion(htx, blk, delta);
if (!ret)
return NULL; /* not enough space */
/* Replace in place or at a new address is the same. We replace all the
* start-line. Only take care to defrag the message if necessary. */
if (ret == 3) {
blk = htx_defrag(htx, blk, (type << 28) + sz + delta);
}
else {
/* Set the new block size and update HTX message */
blk->info = (type << 28) + sz + delta;
htx->data += delta;
}
/* Restore start-line info and flags and copy parts of the start-line */
sl = htx_get_blk_ptr(htx, blk);
sl->info = tmp.info;
sl->flags = tmp.flags;
HTX_SL_P1_LEN(sl) = p1.len;
HTX_SL_P2_LEN(sl) = p2.len;
HTX_SL_P3_LEN(sl) = p3.len;
memcpy(HTX_SL_P1_PTR(sl), p1.ptr, p1.len);
memcpy(HTX_SL_P2_PTR(sl), p2.ptr, p2.len);
memcpy(HTX_SL_P3_PTR(sl), p3.ptr, p3.len);
return sl;
}
/* Reserves the maximum possible size for an HTX data block, by extending an
* existing one or by creating a now one. It returns a compound result with the
* HTX block and the position where new data must be inserted (0 for a new
* block). If an error occurs or if there is no space left, NULL is returned
* instead of a pointer on an HTX block.
*/
struct htx_ret htx_reserve_max_data(struct htx *htx)
{
struct htx_blk *blk, *tailblk;
uint32_t sz, room;
int32_t len = htx_free_data_space(htx);
if (htx->head == -1)
goto rsv_new_block;
if (!len)
return (struct htx_ret){.ret = 0, .blk = NULL};
/* get the tail and head block */
tailblk = htx_get_tail_blk(htx);
if (tailblk == NULL)
goto rsv_new_block;
sz = htx_get_blksz(tailblk);
/* Don't try to append data if the last inserted block is not of the
* same type */
if (htx_get_blk_type(tailblk) != HTX_BLK_DATA)
goto rsv_new_block;
/*
* Same type and enough space: append data
*/
if (!htx->head_addr) {
if (tailblk->addr+sz != htx->tail_addr)
goto rsv_new_block;
room = (htx_pos_to_addr(htx, htx->tail) - htx->tail_addr);
}
else {
if (tailblk->addr+sz != htx->head_addr)
goto rsv_new_block;
room = (htx->end_addr - htx->head_addr);
}
BUG_ON((int32_t)room < 0);
if (room < len)
len = room;
append_data:
htx_change_blk_value_len(htx, tailblk, sz+len);
BUG_ON((int32_t)htx->tail_addr < 0);
BUG_ON((int32_t)htx->head_addr < 0);
BUG_ON(htx->end_addr > htx->tail_addr);
BUG_ON(htx->head_addr > htx->end_addr);
return (struct htx_ret){.ret = sz, .blk = tailblk};
rsv_new_block:
blk = htx_add_blk(htx, HTX_BLK_DATA, len);
if (!blk)
return (struct htx_ret){.ret = 0, .blk = NULL};
blk->info += len;
return (struct htx_ret){.ret = 0, .blk = blk};
}
/* Adds an HTX block of type DATA in <htx>. It first tries to append data if
* possible. It returns the number of bytes consumed from <data>, which may be
* zero if nothing could be copied.
*/
size_t htx_add_data(struct htx *htx, const struct ist data)
{
struct htx_blk *blk, *tailblk;
void *ptr;
uint32_t sz, room;
int32_t len = data.len;
if (htx->head == -1)
goto add_new_block;
/* Not enough space to store data */
if (len > htx_free_data_space(htx))
len = htx_free_data_space(htx);
if (!len)
return 0;
/* get the tail and head block */
tailblk = htx_get_tail_blk(htx);
if (tailblk == NULL)
goto add_new_block;
sz = htx_get_blksz(tailblk);
/* Don't try to append data if the last inserted block is not of the
* same type */
if (htx_get_blk_type(tailblk) != HTX_BLK_DATA)
goto add_new_block;
/*
* Same type and enough space: append data
*/
if (!htx->head_addr) {
if (tailblk->addr+sz != htx->tail_addr)
goto add_new_block;
room = (htx_pos_to_addr(htx, htx->tail) - htx->tail_addr);
}
else {
if (tailblk->addr+sz != htx->head_addr)
goto add_new_block;
room = (htx->end_addr - htx->head_addr);
}
BUG_ON((int32_t)room < 0);
if (room < len)
len = room;
append_data:
/* Append data and update the block itself */
ptr = htx_get_blk_ptr(htx, tailblk);
memcpy(ptr + sz, data.ptr, len);
htx_change_blk_value_len(htx, tailblk, sz+len);
BUG_ON((int32_t)htx->tail_addr < 0);
BUG_ON((int32_t)htx->head_addr < 0);
BUG_ON(htx->end_addr > htx->tail_addr);
BUG_ON(htx->head_addr > htx->end_addr);
return len;
add_new_block:
blk = htx_add_blk(htx, HTX_BLK_DATA, len);
if (!blk)
return 0;
blk->info += len;
memcpy(htx_get_blk_ptr(htx, blk), data.ptr, len);
return len;
}
/* Adds an HTX block of type DATA in <htx> just after all other DATA
* blocks. Because it relies on htx_add_data_atonce(), It may be happened to a
* DATA block if possible. But, if the function succeeds, it will be the last
* DATA block in all cases. If an error occurred, NULL is returned. Otherwise,
* on success, the updated block (or the new one) is returned.
*/
struct htx_blk *htx_add_last_data(struct htx *htx, struct ist data)
{
struct htx_blk *blk, *pblk;
blk = htx_add_data_atonce(htx, data);
if (!blk)
return NULL;
for (pblk = htx_get_prev_blk(htx, blk); pblk; pblk = htx_get_prev_blk(htx, pblk)) {
if (htx_get_blk_type(pblk) <= HTX_BLK_DATA)
break;
/* Swap .addr and .info fields */
blk->addr ^= pblk->addr; pblk->addr ^= blk->addr; blk->addr ^= pblk->addr;
blk->info ^= pblk->info; pblk->info ^= blk->info; blk->info ^= pblk->info;
if (blk->addr == pblk->addr)
blk->addr += htx_get_blksz(pblk);
blk = pblk;
}
return blk;
}
/* Moves the block <blk> just before the block <ref>. Both blocks must be in the
* HTX message <htx> and <blk> must be placed after <ref>. pointer to these
* blocks are updated to remain valid after the move. */
void htx_move_blk_before(struct htx *htx, struct htx_blk **blk, struct htx_blk **ref)
{
struct htx_blk *cblk, *pblk;
cblk = *blk;
for (pblk = htx_get_prev_blk(htx, cblk); pblk; pblk = htx_get_prev_blk(htx, pblk)) {
/* Swap .addr and .info fields */
cblk->addr ^= pblk->addr; pblk->addr ^= cblk->addr; cblk->addr ^= pblk->addr;
cblk->info ^= pblk->info; pblk->info ^= cblk->info; cblk->info ^= pblk->info;
if (cblk->addr == pblk->addr)
cblk->addr += htx_get_blksz(pblk);
if (pblk == *ref)
break;
cblk = pblk;
}
*blk = cblk;
*ref = pblk;
}
/* Append the HTX message <src> to the HTX message <dst>. It returns 1 on
* success and 0 on error. All the message or nothing is copied. If an error
* occurred, all blocks from <src> already appended to <dst> are truncated.
*/
int htx_append_msg(struct htx *dst, const struct htx *src)
{
struct htx_blk *blk, *newblk;
enum htx_blk_type type;
uint32_t blksz, offset = dst->data;
for (blk = htx_get_head_blk(src); blk; blk = htx_get_next_blk(src, blk)) {
type = htx_get_blk_type(blk);
if (type == HTX_BLK_UNUSED)
continue;
blksz = htx_get_blksz(blk);
newblk = htx_add_blk(dst, type, blksz);
if (!newblk)
goto error;
newblk->info = blk->info;
memcpy(htx_get_blk_ptr(dst, newblk), htx_get_blk_ptr(src, blk), blksz);
}
return 1;
error:
htx_truncate(dst, offset);
return 0;
}