haproxy/src/hq_interop.c
Amaury Denoyelle 30e260e2e6 MEDIUM: mux-quic: implement http-request timeout
Implement http-request timeout for QUIC MUX. It is used when the
connection is opened and is triggered if no HTTP request is received in
time. By HTTP request we mean at least a QUIC stream with a full header
section. Then qcs instance is attached to a sedesc and upper layer is
then responsible to wait for the rest of the request.

This timeout is also used when new QUIC streams are opened during the
connection lifetime to wait for full HTTP request on them. As it's
possible to demux multiple streams in parallel with QUIC, each waiting
stream is registered in a list <opening_list> stored in qcc with <start>
as timestamp in qcs for the stream opening. Once a qcs is attached to a
sedesc, it is removed from <opening_list>. When refreshing MUX timeout,
if <opening_list> is not empty, the first waiting stream is used to set
MUX timeout.

This is efficient as streams are stored in the list in their creation
order so CPU usage is minimal. Also, the size of the list is
automatically restricted by flow control limitation so it should not
grow too much.

Streams are insert in <opening_list> by application protocol layer. This
is because only application protocol can differentiate streams for HTTP
messaging from internal usage. A function qcs_wait_http_req() has been
added to register a request stream by app layer. QUIC MUX can then
remove it from the list in qc_attach_sc().

As a side-note, it was necessary to implement attach qcc_app_ops
callback on hq-interop module to be able to insert a stream in waiting
list. Without this, a BUG_ON statement would be triggered when trying to
remove the stream on sedesc attach. This is to ensure that every
requests streams are registered for http-request timeout.

MUX timeout is explicitely refreshed on MAX_STREAM_DATA and STOP_SENDING
frame parsing to schedule http-request timeout if a new stream has been
instantiated. It was already done on STREAM parsing due to a previous
patch.
2022-08-03 15:04:18 +02:00

178 lines
3.5 KiB
C

#include <haproxy/hq_interop.h>
#include <import/ist.h>
#include <haproxy/buf.h>
#include <haproxy/connection.h>
#include <haproxy/dynbuf.h>
#include <haproxy/htx.h>
#include <haproxy/http.h>
#include <haproxy/mux_quic.h>
static ssize_t hq_interop_decode_qcs(struct qcs *qcs, struct buffer *b, int fin)
{
struct htx *htx;
struct htx_sl *sl;
struct stconn *sc;
struct buffer htx_buf = BUF_NULL;
struct ist path;
char *ptr = b_head(b);
char *end = b_wrap(b);
size_t size = b_size(b);
size_t data = b_data(b);
b_alloc(&htx_buf);
htx = htx_from_buf(&htx_buf);
/* skip method */
while (data && HTTP_IS_TOKEN(*ptr)) {
if (++ptr == end)
ptr -= size;
data--;
}
if (!data || !HTTP_IS_SPHT(*ptr)) {
fprintf(stderr, "truncated stream\n");
return 0;
}
if (++ptr == end)
ptr -= size;
if (!--data) {
fprintf(stderr, "truncated stream\n");
return 0;
}
/* extract path */
BUG_ON(HTTP_IS_LWS(*ptr));
path.ptr = ptr;
while (data && !HTTP_IS_LWS(*ptr)) {
if (++ptr == end)
ptr -= size;
data--;
}
if (!data) {
fprintf(stderr, "truncated stream\n");
return 0;
}
BUG_ON(!HTTP_IS_LWS(*ptr));
path.len = ptr - path.ptr;
sl = htx_add_stline(htx, HTX_BLK_REQ_SL, 0, ist("GET"), path, ist("HTTP/1.0"));
if (!sl)
return -1;
sl->flags |= HTX_SL_F_BODYLESS;
sl->info.req.meth = find_http_meth("GET", 3);
htx_add_endof(htx, HTX_BLK_EOH);
htx_to_buf(htx, &htx_buf);
sc = qc_attach_sc(qcs, &htx_buf);
if (!sc)
return -1;
b_free(&htx_buf);
if (fin)
htx->flags |= HTX_FL_EOM;
return b_data(b);
}
static struct buffer *mux_get_buf(struct qcs *qcs)
{
if (!b_size(&qcs->tx.buf))
b_alloc(&qcs->tx.buf);
return &qcs->tx.buf;
}
static size_t hq_interop_snd_buf(struct stconn *sc, struct buffer *buf,
size_t count, int flags)
{
struct qcs *qcs = __sc_mux_strm(sc);
struct htx *htx;
enum htx_blk_type btype;
struct htx_blk *blk;
int32_t idx;
uint32_t bsize, fsize;
struct buffer *res, outbuf;
size_t total = 0;
htx = htx_from_buf(buf);
res = mux_get_buf(qcs);
outbuf = b_make(b_tail(res), b_contig_space(res), 0, 0);
while (count && !htx_is_empty(htx) && !(qcs->flags & QC_SF_BLK_MROOM)) {
/* Not implemented : QUIC on backend side */
idx = htx_get_head(htx);
blk = htx_get_blk(htx, idx);
btype = htx_get_blk_type(blk);
fsize = bsize = htx_get_blksz(blk);
BUG_ON(btype == HTX_BLK_REQ_SL);
switch (btype) {
case HTX_BLK_DATA:
if (fsize > count)
fsize = count;
if (b_room(&outbuf) < fsize)
fsize = b_room(&outbuf);
if (!fsize) {
qcs->flags |= QC_SF_BLK_MROOM;
goto end;
}
b_putblk(&outbuf, htx_get_blk_ptr(htx, blk), fsize);
total += fsize;
count -= fsize;
if (fsize == bsize)
htx_remove_blk(htx, blk);
else
htx_cut_data_blk(htx, blk, fsize);
break;
/* only body is transferred on HTTP/0.9 */
case HTX_BLK_RES_SL:
case HTX_BLK_TLR:
case HTX_BLK_EOT:
default:
htx_remove_blk(htx, blk);
total += bsize;
count -= bsize;
break;
}
}
end:
if ((htx->flags & HTX_FL_EOM) && htx_is_empty(htx))
qcs->flags |= QC_SF_FIN_STREAM;
b_add(res, b_data(&outbuf));
if (total) {
if (!(qcs->qcc->wait_event.events & SUB_RETRY_SEND))
tasklet_wakeup(qcs->qcc->wait_event.tasklet);
}
return total;
}
static int hq_interop_attach(struct qcs *qcs, void *conn_ctx)
{
qcs_wait_http_req(qcs);
return 0;
}
const struct qcc_app_ops hq_interop_ops = {
.decode_qcs = hq_interop_decode_qcs,
.snd_buf = hq_interop_snd_buf,
.attach = hq_interop_attach,
};