blob: 764c0283067e529510c0ce8d42c0a4f26433dcce [file] [log] [blame]
/*
* HTTP/2 mux-demux for connections
*
* Copyright 2017 Willy Tarreau <w@1wt.eu>
*
* 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 <common/cfgparse.h>
#include <common/config.h>
#include <common/h2.h>
#include <common/hpack-dec.h>
#include <common/hpack-enc.h>
#include <common/hpack-tbl.h>
#include <common/net_helper.h>
#include <proto/connection.h>
#include <proto/h1.h>
#include <proto/stream.h>
#include <types/session.h>
#include <eb32tree.h>
/* dummy streams returned for idle and closed states */
static const struct h2s *h2_closed_stream;
static const struct h2s *h2_idle_stream;
/* the h2c connection pool */
static struct pool_head *pool_head_h2c;
/* the h2s stream pool */
static struct pool_head *pool_head_h2s;
/* Connection flags (32 bit), in h2c->flags */
#define H2_CF_NONE 0x00000000
/* Flags indicating why writing to the mux is blocked. */
#define H2_CF_MUX_MALLOC 0x00000001 // mux blocked on lack of connection's mux buffer
#define H2_CF_MUX_MFULL 0x00000002 // mux blocked on connection's mux buffer full
#define H2_CF_MUX_BLOCK_ANY 0x00000003 // aggregate of the mux flags above
/* Flags indicating why writing to the demux is blocked.
* The first two ones directly affect the ability for the mux to receive data
* from the connection. The other ones affect the mux's ability to demux
* received data.
*/
#define H2_CF_DEM_DALLOC 0x00000004 // demux blocked on lack of connection's demux buffer
#define H2_CF_DEM_DFULL 0x00000008 // demux blocked on connection's demux buffer full
#define H2_CF_DEM_MBUSY 0x00000010 // demux blocked on connection's mux side busy
#define H2_CF_DEM_MROOM 0x00000020 // demux blocked on lack of room in mux buffer
#define H2_CF_DEM_SALLOC 0x00000040 // demux blocked on lack of stream's request buffer
#define H2_CF_DEM_SFULL 0x00000080 // demux blocked on stream request buffer full
#define H2_CF_DEM_TOOMANY 0x00000100 // demux blocked waiting for some conn_streams to leave
#define H2_CF_DEM_BLOCK_ANY 0x000001F0 // aggregate of the demux flags above except DALLOC/DFULL
/* other flags */
#define H2_CF_GOAWAY_SENT 0x00001000 // a GOAWAY frame was successfully sent
#define H2_CF_GOAWAY_FAILED 0x00002000 // a GOAWAY frame failed to be sent
#define H2_CF_WAIT_FOR_HS 0x00004000 // We did check that at least a stream was waiting for handshake
/* H2 connection state, in h2c->st0 */
enum h2_cs {
H2_CS_PREFACE, // init done, waiting for connection preface
H2_CS_SETTINGS1, // preface OK, waiting for first settings frame
H2_CS_FRAME_H, // first settings frame ok, waiting for frame header
H2_CS_FRAME_P, // frame header OK, waiting for frame payload
H2_CS_FRAME_A, // frame payload OK, trying to send ACK frame
H2_CS_FRAME_E, // frame payload OK, trying to send RST frame
H2_CS_ERROR, // send GOAWAY(errcode) and close the connection ASAP
H2_CS_ERROR2, // GOAWAY(errcode) sent, close the connection ASAP
H2_CS_ENTRIES // must be last
} __attribute__((packed));
/* H2 connection descriptor */
struct h2c {
struct connection *conn;
enum h2_cs st0; /* mux state */
enum h2_err errcode; /* H2 err code (H2_ERR_*) */
/* 16 bit hole here */
uint32_t flags; /* connection flags: H2_CF_* */
int32_t max_id; /* highest ID known on this connection, <0 before preface */
uint32_t rcvd_c; /* newly received data to ACK for the connection */
uint32_t rcvd_s; /* newly received data to ACK for the current stream (dsi) */
/* states for the demux direction */
struct hpack_dht *ddht; /* demux dynamic header table */
struct buffer dbuf; /* demux buffer */
int32_t dsi; /* demux stream ID (<0 = idle) */
int32_t dfl; /* demux frame length (if dsi >= 0) */
int8_t dft; /* demux frame type (if dsi >= 0) */
int8_t dff; /* demux frame flags (if dsi >= 0) */
uint8_t dpl; /* demux pad length (part of dfl), init to 0 */
/* 8 bit hole here */
int32_t last_sid; /* last processed stream ID for GOAWAY, <0 before preface */
/* states for the mux direction */
struct buffer mbuf; /* mux buffer */
int32_t msi; /* mux stream ID (<0 = idle) */
int32_t mfl; /* mux frame length (if dsi >= 0) */
int8_t mft; /* mux frame type (if dsi >= 0) */
int8_t mff; /* mux frame flags (if dsi >= 0) */
/* 16 bit hole here */
int32_t miw; /* mux initial window size for all new streams */
int32_t mws; /* mux window size. Can be negative. */
int32_t mfs; /* mux's max frame size */
int timeout; /* idle timeout duration in ticks */
int shut_timeout; /* idle timeout duration in ticks after GOAWAY was sent */
unsigned int nb_streams; /* number of streams in the tree */
unsigned int nb_cs; /* number of attached conn_streams */
struct task *task; /* timeout management task */
struct eb_root streams_by_id; /* all active streams by their ID */
struct list send_list; /* list of blocked streams requesting to send */
struct list fctl_list; /* list of streams blocked by connection's fctl */
struct buffer_wait buf_wait; /* wait list for buffer allocations */
struct list send_wait_list; /* list of tasks to wake when we're ready to send */
struct wait_list wait_list; /* We're in a wait list, to send */
};
/* H2 stream state, in h2s->st */
enum h2_ss {
H2_SS_IDLE = 0, // idle
H2_SS_RLOC, // reserved(local)
H2_SS_RREM, // reserved(remote)
H2_SS_OPEN, // open
H2_SS_HREM, // half-closed(remote)
H2_SS_HLOC, // half-closed(local)
H2_SS_ERROR, // an error needs to be sent using RST_STREAM
H2_SS_CLOSED, // closed
H2_SS_ENTRIES // must be last
} __attribute__((packed));
/* HTTP/2 stream flags (32 bit), in h2s->flags */
#define H2_SF_NONE 0x00000000
#define H2_SF_ES_RCVD 0x00000001
#define H2_SF_ES_SENT 0x00000002
#define H2_SF_RST_RCVD 0x00000004 // received RST_STREAM
#define H2_SF_RST_SENT 0x00000008 // sent RST_STREAM
/* stream flags indicating the reason the stream is blocked */
#define H2_SF_BLK_MBUSY 0x00000010 // blocked waiting for mux access (transient)
#define H2_SF_BLK_MROOM 0x00000020 // blocked waiting for room in the mux
#define H2_SF_BLK_MFCTL 0x00000040 // blocked due to mux fctl
#define H2_SF_BLK_SFCTL 0x00000080 // blocked due to stream fctl
#define H2_SF_BLK_ANY 0x000000F0 // any of the reasons above
/* stream flags indicating how data is supposed to be sent */
#define H2_SF_DATA_CLEN 0x00000100 // data sent using content-length
#define H2_SF_DATA_CHNK 0x00000200 // data sent using chunked-encoding
/* step we're currently in when sending chunks. This is needed because we may
* have to transfer chunks as large as a full buffer so there's no room left
* for size nor crlf around.
*/
#define H2_SF_CHNK_SIZE 0x00000000 // trying to send chunk size
#define H2_SF_CHNK_DATA 0x00000400 // trying to send chunk data
#define H2_SF_CHNK_CRLF 0x00000800 // trying to send chunk crlf after data
#define H2_SF_CHNK_MASK 0x00000C00 // trying to send chunk size
#define H2_SF_HEADERS_SENT 0x00001000 // a HEADERS frame was sent for this stream
#define H2_SF_OUTGOING_DATA 0x00002000 // set whenever we've seen outgoing data
/* H2 stream descriptor, describing the stream as it appears in the H2C, and as
* it is being processed in the internal HTTP representation (H1 for now).
*/
struct h2s {
struct conn_stream *cs;
struct h2c *h2c;
struct h1m req, res; /* request and response parser state for H1 */
struct eb32_node by_id; /* place in h2c's streams_by_id */
struct list list; /* position in active/blocked lists if blocked>0 */
int32_t id; /* stream ID */
uint32_t flags; /* H2_SF_* */
int mws; /* mux window size for this stream */
enum h2_err errcode; /* H2 err code (H2_ERR_*) */
enum h2_ss st;
};
/* descriptor for an h2 frame header */
struct h2_fh {
uint32_t len; /* length, host order, 24 bits */
uint32_t sid; /* stream id, host order, 31 bits */
uint8_t ft; /* frame type */
uint8_t ff; /* frame flags */
};
/* a few settings from the global section */
static int h2_settings_header_table_size = 4096; /* initial value */
static int h2_settings_initial_window_size = 65535; /* initial value */
static int h2_settings_max_concurrent_streams = 100;
/* a dmumy closed stream */
static const struct h2s *h2_closed_stream = &(const struct h2s){
.cs = NULL,
.h2c = NULL,
.st = H2_SS_CLOSED,
.errcode = H2_ERR_STREAM_CLOSED,
.flags = H2_SF_RST_RCVD,
.id = 0,
};
/* and a dummy idle stream for use with any unannounced stream */
static const struct h2s *h2_idle_stream = &(const struct h2s){
.cs = NULL,
.h2c = NULL,
.st = H2_SS_IDLE,
.errcode = H2_ERR_STREAM_CLOSED,
.id = 0,
};
static struct task *h2_timeout_task(struct task *t, void *context, unsigned short state);
static struct task *h2_send(struct task *t, void *ctx, unsigned short state);
static inline struct h2s *h2c_st_by_id(struct h2c *h2c, int id);
static int h2_frt_decode_headers(struct h2s *h2s);
static int h2_frt_transfer_data(struct h2s *h2s);
/*****************************************************/
/* functions below are for dynamic buffer management */
/*****************************************************/
/* indicates whether or not the we may call the h2_recv() function to attempt
* to receive data into the buffer and/or demux pending data. The condition is
* a bit complex due to some API limits for now. The rules are the following :
* - if an error or a shutdown was detected on the connection and the buffer
* is empty, we must not attempt to receive
* - if the demux buf failed to be allocated, we must not try to receive and
* we know there is nothing pending
* - if no flag indicates a blocking condition, we may attempt to receive,
* regardless of whether the demux buffer is full or not, so that only
* de demux part decides whether or not to block. This is needed because
* the connection API indeed prevents us from re-enabling receipt that is
* already enabled in a polled state, so we must always immediately stop
* as soon as the demux can't proceed so as never to hit an end of read
* with data pending in the buffers.
* - otherwise must may not attempt
*/
static inline int h2_recv_allowed(const struct h2c *h2c)
{
if (b_data(&h2c->dbuf) == 0 &&
(h2c->st0 >= H2_CS_ERROR ||
h2c->conn->flags & CO_FL_ERROR ||
conn_xprt_read0_pending(h2c->conn)))
return 0;
if (!(h2c->flags & H2_CF_DEM_DALLOC) &&
!(h2c->flags & H2_CF_DEM_BLOCK_ANY))
return 1;
return 0;
}
/* returns true if the connection has too many conn_streams attached */
static inline int h2_has_too_many_cs(const struct h2c *h2c)
{
return h2c->nb_cs >= h2_settings_max_concurrent_streams;
}
/* Tries to grab a buffer and to re-enable processing on mux <target>. The h2c
* flags are used to figure what buffer was requested. It returns 1 if the
* allocation succeeds, in which case the connection is woken up, or 0 if it's
* impossible to wake up and we prefer to be woken up later.
*/
static int h2_buf_available(void *target)
{
struct h2c *h2c = target;
struct h2s *h2s;
if ((h2c->flags & H2_CF_DEM_DALLOC) && b_alloc_margin(&h2c->dbuf, 0)) {
h2c->flags &= ~H2_CF_DEM_DALLOC;
if (h2_recv_allowed(h2c))
conn_xprt_want_recv(h2c->conn);
return 1;
}
if ((h2c->flags & H2_CF_MUX_MALLOC) && b_alloc_margin(&h2c->mbuf, 0)) {
h2c->flags &= ~H2_CF_MUX_MALLOC;
if (!(h2c->flags & H2_CF_MUX_BLOCK_ANY))
conn_xprt_want_send(h2c->conn);
if (h2c->flags & H2_CF_DEM_MROOM) {
h2c->flags &= ~H2_CF_DEM_MROOM;
if (h2_recv_allowed(h2c))
conn_xprt_want_recv(h2c->conn);
}
return 1;
}
if ((h2c->flags & H2_CF_DEM_SALLOC) &&
(h2s = h2c_st_by_id(h2c, h2c->dsi)) && h2s->cs &&
b_alloc_margin(&h2s->cs->rxbuf, 0)) {
h2c->flags &= ~H2_CF_DEM_SALLOC;
if (h2_recv_allowed(h2c))
conn_xprt_want_recv(h2c->conn);
return 1;
}
return 0;
}
static inline struct buffer *h2_get_buf(struct h2c *h2c, struct buffer *bptr)
{
struct buffer *buf = NULL;
if (likely(LIST_ISEMPTY(&h2c->buf_wait.list)) &&
unlikely((buf = b_alloc_margin(bptr, 0)) == NULL)) {
h2c->buf_wait.target = h2c;
h2c->buf_wait.wakeup_cb = h2_buf_available;
HA_SPIN_LOCK(BUF_WQ_LOCK, &buffer_wq_lock);
LIST_ADDQ(&buffer_wq, &h2c->buf_wait.list);
HA_SPIN_UNLOCK(BUF_WQ_LOCK, &buffer_wq_lock);
__conn_xprt_stop_recv(h2c->conn);
}
return buf;
}
static inline void h2_release_buf(struct h2c *h2c, struct buffer *bptr)
{
if (bptr->size) {
b_free(bptr);
offer_buffers(h2c->buf_wait.target, tasks_run_queue);
}
}
/*****************************************************************/
/* functions below are dedicated to the mux setup and management */
/*****************************************************************/
/* tries to initialize the inbound h2c mux. Returns < 0 in case of failure. */
static int h2c_frt_init(struct connection *conn)
{
struct h2c *h2c;
struct task *t = NULL;
struct session *sess = conn->owner;
h2c = pool_alloc(pool_head_h2c);
if (!h2c)
goto fail;
h2c->shut_timeout = h2c->timeout = sess->fe->timeout.client;
if (tick_isset(sess->fe->timeout.clientfin))
h2c->shut_timeout = sess->fe->timeout.clientfin;
h2c->task = NULL;
if (tick_isset(h2c->timeout)) {
t = task_new(tid_bit);
if (!t)
goto fail;
h2c->task = t;
t->process = h2_timeout_task;
t->context = h2c;
t->expire = tick_add(now_ms, h2c->timeout);
}
h2c->wait_list.task = tasklet_new();
if (!h2c->wait_list.task)
goto fail;
h2c->wait_list.task->process = h2_send;
h2c->wait_list.task->context = conn;
h2c->ddht = hpack_dht_alloc(h2_settings_header_table_size);
if (!h2c->ddht)
goto fail;
/* Initialise the context. */
h2c->st0 = H2_CS_PREFACE;
h2c->conn = conn;
h2c->max_id = -1;
h2c->errcode = H2_ERR_NO_ERROR;
h2c->flags = H2_CF_NONE;
h2c->rcvd_c = 0;
h2c->rcvd_s = 0;
h2c->nb_streams = 0;
h2c->nb_cs = 0;
h2c->dbuf = BUF_NULL;
h2c->dsi = -1;
h2c->msi = -1;
h2c->last_sid = -1;
h2c->mbuf = BUF_NULL;
h2c->miw = 65535; /* mux initial window size */
h2c->mws = 65535; /* mux window size */
h2c->mfs = 16384; /* initial max frame size */
h2c->streams_by_id = EB_ROOT_UNIQUE;
LIST_INIT(&h2c->send_list);
LIST_INIT(&h2c->fctl_list);
LIST_INIT(&h2c->buf_wait.list);
conn->mux_ctx = h2c;
if (t)
task_queue(t);
conn_xprt_want_recv(conn);
LIST_INIT(&h2c->send_wait_list);
LIST_INIT(&h2c->wait_list.list);
/* mux->wake will be called soon to complete the operation */
return 0;
fail:
if (t)
task_free(t);
if (h2c->wait_list.task)
tasklet_free(h2c->wait_list.task);
pool_free(pool_head_h2c, h2c);
return -1;
}
/* Initialize the mux once it's attached. For outgoing connections, the context
* is already initialized before installing the mux, so we detect incoming
* connections from the fact that the context is still NULL. Returns < 0 on
* error.
*/
static int h2_init(struct connection *conn)
{
if (conn->mux_ctx) {
/* we don't support outgoing connections for now */
return -1;
}
return h2c_frt_init(conn);
}
/* returns the stream associated with id <id> or NULL if not found */
static inline struct h2s *h2c_st_by_id(struct h2c *h2c, int id)
{
struct eb32_node *node;
if (id > h2c->max_id)
return (struct h2s *)h2_idle_stream;
node = eb32_lookup(&h2c->streams_by_id, id);
if (!node)
return (struct h2s *)h2_closed_stream;
return container_of(node, struct h2s, by_id);
}
/* release function for a connection. This one should be called to free all
* resources allocated to the mux.
*/
static void h2_release(struct connection *conn)
{
struct h2c *h2c = conn->mux_ctx;
LIST_DEL(&conn->list);
if (h2c) {
hpack_dht_free(h2c->ddht);
HA_SPIN_LOCK(BUF_WQ_LOCK, &buffer_wq_lock);
LIST_DEL(&h2c->buf_wait.list);
HA_SPIN_UNLOCK(BUF_WQ_LOCK, &buffer_wq_lock);
h2_release_buf(h2c, &h2c->dbuf);
h2_release_buf(h2c, &h2c->mbuf);
if (h2c->task) {
h2c->task->context = NULL;
task_wakeup(h2c->task, TASK_WOKEN_OTHER);
h2c->task = NULL;
}
if (h2c->wait_list.task)
tasklet_free(h2c->wait_list.task);
pool_free(pool_head_h2c, h2c);
}
conn->mux = NULL;
conn->mux_ctx = NULL;
conn_stop_tracking(conn);
conn_full_close(conn);
if (conn->destroy_cb)
conn->destroy_cb(conn);
conn_free(conn);
}
/******************************************************/
/* functions below are for the H2 protocol processing */
/******************************************************/
/* returns the stream if of stream <h2s> or 0 if <h2s> is NULL */
static inline __maybe_unused int h2s_id(const struct h2s *h2s)
{
return h2s ? h2s->id : 0;
}
/* returns true of the mux is currently busy as seen from stream <h2s> */
static inline __maybe_unused int h2c_mux_busy(const struct h2c *h2c, const struct h2s *h2s)
{
if (h2c->msi < 0)
return 0;
if (h2c->msi == h2s_id(h2s))
return 0;
return 1;
}
/* marks an error on the connection */
static inline __maybe_unused void h2c_error(struct h2c *h2c, enum h2_err err)
{
h2c->errcode = err;
h2c->st0 = H2_CS_ERROR;
}
/* marks an error on the stream */
static inline __maybe_unused void h2s_error(struct h2s *h2s, enum h2_err err)
{
if (h2s->st > H2_SS_IDLE && h2s->st < H2_SS_ERROR) {
h2s->errcode = err;
h2s->st = H2_SS_ERROR;
if (h2s->cs)
h2s->cs->flags |= CS_FL_ERROR;
}
}
/* writes the 24-bit frame size <len> at address <frame> */
static inline __maybe_unused void h2_set_frame_size(void *frame, uint32_t len)
{
uint8_t *out = frame;
*out = len >> 16;
write_n16(out + 1, len);
}
/* reads <bytes> bytes from buffer <b> starting at relative offset <o> from the
* current pointer, dealing with wrapping, and stores the result in <dst>. It's
* the caller's responsibility to verify that there are at least <bytes> bytes
* available in the buffer's input prior to calling this function. The buffer
* is assumed not to hold any output data.
*/
static inline __maybe_unused void h2_get_buf_bytes(void *dst, size_t bytes,
const struct buffer *b, int o)
{
readv_bytes(dst, bytes, b_peek(b, o), b_wrap(b) - b_peek(b, o), b_orig(b));
}
static inline __maybe_unused uint16_t h2_get_n16(const struct buffer *b, int o)
{
return readv_n16(b_peek(b, o), b_wrap(b) - b_peek(b, o), b_orig(b));
}
static inline __maybe_unused uint32_t h2_get_n32(const struct buffer *b, int o)
{
return readv_n32(b_peek(b, o), b_wrap(b) - b_peek(b, o), b_orig(b));
}
static inline __maybe_unused uint64_t h2_get_n64(const struct buffer *b, int o)
{
return readv_n64(b_peek(b, o), b_wrap(b) - b_peek(b, o), b_orig(b));
}
/* Peeks an H2 frame header from buffer <b> into descriptor <h>. The algorithm
* is not obvious. It turns out that H2 headers are neither aligned nor do they
* use regular sizes. And to add to the trouble, the buffer may wrap so each
* byte read must be checked. The header is formed like this :
*
* b0 b1 b2 b3 b4 b5..b8
* +----------+---------+--------+----+----+----------------------+
* |len[23:16]|len[15:8]|len[7:0]|type|flag|sid[31:0] (big endian)|
* +----------+---------+--------+----+----+----------------------+
*
* Here we read a big-endian 64 bit word from h[1]. This way in a single read
* we get the sid properly aligned and ordered, and 16 bits of len properly
* ordered as well. The type and flags can be extracted using bit shifts from
* the word, and only one extra read is needed to fetch len[16:23].
* Returns zero if some bytes are missing, otherwise non-zero on success. The
* buffer is assumed not to contain any output data.
*/
static __maybe_unused int h2_peek_frame_hdr(const struct buffer *b, struct h2_fh *h)
{
uint64_t w;
if (b_data(b) < 9)
return 0;
w = h2_get_n64(b, 1);
h->len = *(uint8_t*)b_head(b) << 16;
h->sid = w & 0x7FFFFFFF; /* RFC7540#4.1: R bit must be ignored */
h->ff = w >> 32;
h->ft = w >> 40;
h->len += w >> 48;
return 1;
}
/* skip the next 9 bytes corresponding to the frame header possibly parsed by
* h2_peek_frame_hdr() above.
*/
static inline __maybe_unused void h2_skip_frame_hdr(struct buffer *b)
{
b_del(b, 9);
}
/* same as above, automatically advances the buffer on success */
static inline __maybe_unused int h2_get_frame_hdr(struct buffer *b, struct h2_fh *h)
{
int ret;
ret = h2_peek_frame_hdr(b, h);
if (ret > 0)
h2_skip_frame_hdr(b);
return ret;
}
/* marks stream <h2s> as CLOSED and decrement the number of active streams for
* its connection if the stream was not yet closed. Please use this exclusively
* before closing a stream to ensure stream count is well maintained.
*/
static inline void h2s_close(struct h2s *h2s)
{
if (h2s->st != H2_SS_CLOSED)
h2s->h2c->nb_streams--;
h2s->st = H2_SS_CLOSED;
}
/* detaches an H2 stream from its H2C and releases it to the H2S pool. */
static void h2s_destroy(struct h2s *h2s)
{
h2s_close(h2s);
LIST_DEL(&h2s->list);
LIST_INIT(&h2s->list);
eb32_delete(&h2s->by_id);
pool_free(pool_head_h2s, h2s);
}
/* creates a new stream <id> on the h2c connection and returns it, or NULL in
* case of memory allocation error.
*/
static struct h2s *h2c_stream_new(struct h2c *h2c, int id)
{
struct conn_stream *cs;
struct h2s *h2s;
h2s = pool_alloc(pool_head_h2s);
if (!h2s)
goto out;
h2s->h2c = h2c;
h2s->mws = h2c->miw;
h2s->flags = H2_SF_NONE;
h2s->errcode = H2_ERR_NO_ERROR;
h2s->st = H2_SS_IDLE;
h1m_init(&h2s->req);
h1m_init(&h2s->res);
h2s->by_id.key = h2s->id = id;
h2c->max_id = id;
LIST_INIT(&h2s->list);
eb32_insert(&h2c->streams_by_id, &h2s->by_id);
h2c->nb_streams++;
if (h2c->nb_streams > h2_settings_max_concurrent_streams)
goto out_close;
cs = cs_new(h2c->conn);
if (!cs)
goto out_close;
h2s->cs = cs;
cs->ctx = h2s;
h2c->nb_cs++;
if (stream_create_from_cs(cs) < 0)
goto out_free_cs;
/* OK done, the stream lives its own life now */
if (h2_has_too_many_cs(h2c))
h2c->flags |= H2_CF_DEM_TOOMANY;
return h2s;
out_free_cs:
h2c->nb_cs--;
cs_free(cs);
out_close:
h2s_destroy(h2s);
h2s = NULL;
out:
return h2s;
}
/* try to send a settings frame on the connection. Returns > 0 on success, 0 if
* it couldn't do anything. It may return an error in h2c. See RFC7540#11.3 for
* the various settings codes.
*/
static int h2c_snd_settings(struct h2c *h2c)
{
struct buffer *res;
char buf_data[100]; // enough for 15 settings
struct buffer buf;
int ret;
if (h2c_mux_busy(h2c, NULL)) {
h2c->flags |= H2_CF_DEM_MBUSY;
return 0;
}
res = h2_get_buf(h2c, &h2c->mbuf);
if (!res) {
h2c->flags |= H2_CF_MUX_MALLOC;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
chunk_init(&buf, buf_data, sizeof(buf_data));
chunk_memcpy(&buf,
"\x00\x00\x00" /* length : 0 for now */
"\x04\x00" /* type : 4 (settings), flags : 0 */
"\x00\x00\x00\x00", /* stream ID : 0 */
9);
if (h2_settings_header_table_size != 4096) {
char str[6] = "\x00\x01"; /* header_table_size */
write_n32(str + 2, h2_settings_header_table_size);
chunk_memcat(&buf, str, 6);
}
if (h2_settings_initial_window_size != 65535) {
char str[6] = "\x00\x04"; /* initial_window_size */
write_n32(str + 2, h2_settings_initial_window_size);
chunk_memcat(&buf, str, 6);
}
if (h2_settings_max_concurrent_streams != 0) {
char str[6] = "\x00\x03"; /* max_concurrent_streams */
/* Note: 0 means "unlimited" for haproxy's config but not for
* the protocol, so never send this value!
*/
write_n32(str + 2, h2_settings_max_concurrent_streams);
chunk_memcat(&buf, str, 6);
}
if (global.tune.bufsize != 16384) {
char str[6] = "\x00\x05"; /* max_frame_size */
/* note: similarly we could also emit MAX_HEADER_LIST_SIZE to
* match bufsize - rewrite size, but at the moment it seems
* that clients don't take care of it.
*/
write_n32(str + 2, global.tune.bufsize);
chunk_memcat(&buf, str, 6);
}
h2_set_frame_size(buf.area, buf.data - 9);
ret = b_istput(res, ist2(buf.area, buf.data));
if (unlikely(ret <= 0)) {
if (!ret) {
h2c->flags |= H2_CF_MUX_MFULL;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
else {
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
return 0;
}
}
return ret;
}
/* Try to receive a connection preface, then upon success try to send our
* preface which is a SETTINGS frame. Returns > 0 on success or zero on
* missing data. It may return an error in h2c.
*/
static int h2c_frt_recv_preface(struct h2c *h2c)
{
int ret1;
int ret2;
ret1 = b_isteq(&h2c->dbuf, 0, b_data(&h2c->dbuf), ist(H2_CONN_PREFACE));
if (unlikely(ret1 <= 0)) {
if (ret1 < 0 || conn_xprt_read0_pending(h2c->conn))
h2c_error(h2c, H2_ERR_PROTOCOL_ERROR);
return 0;
}
ret2 = h2c_snd_settings(h2c);
if (ret2 > 0)
b_del(&h2c->dbuf, ret1);
return ret2;
}
/* try to send a GOAWAY frame on the connection to report an error or a graceful
* shutdown, with h2c->errcode as the error code. Returns > 0 on success or zero
* if nothing was done. It uses h2c->last_sid as the advertised ID, or copies it
* from h2c->max_id if it's not set yet (<0). In case of lack of room to write
* the message, it subscribes the requester (either <h2s> or <h2c>) to future
* notifications. It sets H2_CF_GOAWAY_SENT on success, and H2_CF_GOAWAY_FAILED
* on unrecoverable failure. It will not attempt to send one again in this last
* case so that it is safe to use h2c_error() to report such errors.
*/
static int h2c_send_goaway_error(struct h2c *h2c, struct h2s *h2s)
{
struct buffer *res;
char str[17];
int ret;
if (h2c->flags & H2_CF_GOAWAY_FAILED)
return 1; // claim that it worked
if (h2c_mux_busy(h2c, h2s)) {
if (h2s)
h2s->flags |= H2_SF_BLK_MBUSY;
else
h2c->flags |= H2_CF_DEM_MBUSY;
return 0;
}
res = h2_get_buf(h2c, &h2c->mbuf);
if (!res) {
h2c->flags |= H2_CF_MUX_MALLOC;
if (h2s)
h2s->flags |= H2_SF_BLK_MROOM;
else
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
/* len: 8, type: 7, flags: none, sid: 0 */
memcpy(str, "\x00\x00\x08\x07\x00\x00\x00\x00\x00", 9);
if (h2c->last_sid < 0)
h2c->last_sid = h2c->max_id;
write_n32(str + 9, h2c->last_sid);
write_n32(str + 13, h2c->errcode);
ret = b_istput(res, ist2(str, 17));
if (unlikely(ret <= 0)) {
if (!ret) {
h2c->flags |= H2_CF_MUX_MFULL;
if (h2s)
h2s->flags |= H2_SF_BLK_MROOM;
else
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
else {
/* we cannot report this error using GOAWAY, so we mark
* it and claim a success.
*/
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
h2c->flags |= H2_CF_GOAWAY_FAILED;
return 1;
}
}
h2c->flags |= H2_CF_GOAWAY_SENT;
return ret;
}
/* Try to send an RST_STREAM frame on the connection for the indicated stream
* during mux operations. This stream must be valid and cannot be closed
* already. h2s->id will be used for the stream ID and h2s->errcode will be
* used for the error code. h2s->st will be update to H2_SS_CLOSED if it was
* not yet.
*
* Returns > 0 on success or zero if nothing was done. In case of lack of room
* to write the message, it subscribes the stream to future notifications.
*/
static int h2s_send_rst_stream(struct h2c *h2c, struct h2s *h2s)
{
struct buffer *res;
char str[13];
int ret;
if (!h2s || h2s->st == H2_SS_CLOSED)
return 1;
/* RFC7540#5.4.2: To avoid looping, an endpoint MUST NOT send a
* RST_STREAM in response to a RST_STREAM frame.
*/
if (h2c->dft == H2_FT_RST_STREAM) {
ret = 1;
goto ignore;
}
if (h2c_mux_busy(h2c, h2s)) {
h2s->flags |= H2_SF_BLK_MBUSY;
return 0;
}
res = h2_get_buf(h2c, &h2c->mbuf);
if (!res) {
h2c->flags |= H2_CF_MUX_MALLOC;
h2s->flags |= H2_SF_BLK_MROOM;
return 0;
}
/* len: 4, type: 3, flags: none */
memcpy(str, "\x00\x00\x04\x03\x00", 5);
write_n32(str + 5, h2s->id);
write_n32(str + 9, h2s->errcode);
ret = b_istput(res, ist2(str, 13));
if (unlikely(ret <= 0)) {
if (!ret) {
h2c->flags |= H2_CF_MUX_MFULL;
h2s->flags |= H2_SF_BLK_MROOM;
return 0;
}
else {
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
return 0;
}
}
ignore:
h2s->flags |= H2_SF_RST_SENT;
h2s_close(h2s);
return ret;
}
/* Try to send an RST_STREAM frame on the connection for the stream being
* demuxed using h2c->dsi for the stream ID. It will use h2s->errcode as the
* error code unless the stream's state already is IDLE or CLOSED in which
* case STREAM_CLOSED will be used, and will update h2s->st to H2_SS_CLOSED if
* it was not yet.
*
* Returns > 0 on success or zero if nothing was done. In case of lack of room
* to write the message, it blocks the demuxer and subscribes it to future
* notifications. It's worth mentionning that an RST may even be sent for a
* closed stream.
*/
static int h2c_send_rst_stream(struct h2c *h2c, struct h2s *h2s)
{
struct buffer *res;
char str[13];
int ret;
/* RFC7540#5.4.2: To avoid looping, an endpoint MUST NOT send a
* RST_STREAM in response to a RST_STREAM frame.
*/
if (h2c->dft == H2_FT_RST_STREAM) {
ret = 1;
goto ignore;
}
if (h2c_mux_busy(h2c, h2s)) {
h2c->flags |= H2_CF_DEM_MBUSY;
return 0;
}
res = h2_get_buf(h2c, &h2c->mbuf);
if (!res) {
h2c->flags |= H2_CF_MUX_MALLOC;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
/* len: 4, type: 3, flags: none */
memcpy(str, "\x00\x00\x04\x03\x00", 5);
write_n32(str + 5, h2c->dsi);
write_n32(str + 9, (h2s->st > H2_SS_IDLE && h2s->st < H2_SS_CLOSED) ?
h2s->errcode : H2_ERR_STREAM_CLOSED);
ret = b_istput(res, ist2(str, 13));
if (unlikely(ret <= 0)) {
if (!ret) {
h2c->flags |= H2_CF_MUX_MFULL;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
else {
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
return 0;
}
}
ignore:
if (h2s->st > H2_SS_IDLE && h2s->st < H2_SS_CLOSED) {
h2s->flags |= H2_SF_RST_SENT;
h2s_close(h2s);
}
return ret;
}
/* try to send an empty DATA frame with the ES flag set to notify about the
* end of stream and match a shutdown(write). If an ES was already sent as
* indicated by HLOC/ERROR/RESET/CLOSED states, nothing is done. Returns > 0
* on success or zero if nothing was done. In case of lack of room to write the
* message, it subscribes the requesting stream to future notifications.
*/
static int h2_send_empty_data_es(struct h2s *h2s)
{
struct h2c *h2c = h2s->h2c;
struct buffer *res;
char str[9];
int ret;
if (h2s->st == H2_SS_HLOC || h2s->st == H2_SS_ERROR || h2s->st == H2_SS_CLOSED)
return 1;
if (h2c_mux_busy(h2c, h2s)) {
h2s->flags |= H2_SF_BLK_MBUSY;
return 0;
}
res = h2_get_buf(h2c, &h2c->mbuf);
if (!res) {
h2c->flags |= H2_CF_MUX_MALLOC;
h2s->flags |= H2_SF_BLK_MROOM;
return 0;
}
/* len: 0x000000, type: 0(DATA), flags: ES=1 */
memcpy(str, "\x00\x00\x00\x00\x01", 5);
write_n32(str + 5, h2s->id);
ret = b_istput(res, ist2(str, 9));
if (likely(ret > 0)) {
h2s->flags |= H2_SF_ES_SENT;
}
else if (!ret) {
h2c->flags |= H2_CF_MUX_MFULL;
h2s->flags |= H2_SF_BLK_MROOM;
return 0;
}
else {
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
return 0;
}
return ret;
}
/* wake the streams attached to the connection, whose id is greater than <last>,
* and assign their conn_stream the CS_FL_* flags <flags> in addition to
* CS_FL_ERROR in case of error and CS_FL_EOS in case of closed connection. The
* stream's state is automatically updated accordingly.
*/
static void h2_wake_some_streams(struct h2c *h2c, int last, uint32_t flags)
{
struct eb32_node *node;
struct h2s *h2s;
if (h2c->st0 >= H2_CS_ERROR || h2c->conn->flags & CO_FL_ERROR)
flags |= CS_FL_ERROR;
if (conn_xprt_read0_pending(h2c->conn))
flags |= CS_FL_EOS;
node = eb32_lookup_ge(&h2c->streams_by_id, last + 1);
while (node) {
h2s = container_of(node, struct h2s, by_id);
if (h2s->id <= last)
break;
node = eb32_next(node);
if (!h2s->cs) {
/* this stream was already orphaned */
h2s_destroy(h2s);
continue;
}
h2s->cs->flags |= flags;
h2s->cs->data_cb->wake(h2s->cs);
if (flags & CS_FL_ERROR && h2s->st < H2_SS_ERROR)
h2s->st = H2_SS_ERROR;
else if (flags & CS_FL_EOS && h2s->st == H2_SS_OPEN)
h2s->st = H2_SS_HREM;
else if (flags & CS_FL_EOS && h2s->st == H2_SS_HLOC)
h2s_close(h2s);
}
}
/* Increase all streams' outgoing window size by the difference passed in
* argument. This is needed upon receipt of the settings frame if the initial
* window size is different. The difference may be negative and the resulting
* window size as well, for the time it takes to receive some window updates.
*/
static void h2c_update_all_ws(struct h2c *h2c, int diff)
{
struct h2s *h2s;
struct eb32_node *node;
if (!diff)
return;
node = eb32_first(&h2c->streams_by_id);
while (node) {
h2s = container_of(node, struct h2s, by_id);
h2s->mws += diff;
node = eb32_next(node);
}
}
/* processes a SETTINGS frame whose payload is <payload> for <plen> bytes, and
* ACKs it if needed. Returns > 0 on success or zero on missing data. It may
* return an error in h2c. Described in RFC7540#6.5.
*/
static int h2c_handle_settings(struct h2c *h2c)
{
unsigned int offset;
int error;
if (h2c->dff & H2_F_SETTINGS_ACK) {
if (h2c->dfl) {
error = H2_ERR_FRAME_SIZE_ERROR;
goto fail;
}
return 1;
}
if (h2c->dsi != 0) {
error = H2_ERR_PROTOCOL_ERROR;
goto fail;
}
if (h2c->dfl % 6) {
error = H2_ERR_FRAME_SIZE_ERROR;
goto fail;
}
/* that's the limit we can process */
if (h2c->dfl > global.tune.bufsize) {
error = H2_ERR_FRAME_SIZE_ERROR;
goto fail;
}
/* process full frame only */
if (b_data(&h2c->dbuf) < h2c->dfl)
return 0;
/* parse the frame */
for (offset = 0; offset < h2c->dfl; offset += 6) {
uint16_t type = h2_get_n16(&h2c->dbuf, offset);
int32_t arg = h2_get_n32(&h2c->dbuf, offset + 2);
switch (type) {
case H2_SETTINGS_INITIAL_WINDOW_SIZE:
/* we need to update all existing streams with the
* difference from the previous iws.
*/
if (arg < 0) { // RFC7540#6.5.2
error = H2_ERR_FLOW_CONTROL_ERROR;
goto fail;
}
h2c_update_all_ws(h2c, arg - h2c->miw);
h2c->miw = arg;
break;
case H2_SETTINGS_MAX_FRAME_SIZE:
if (arg < 16384 || arg > 16777215) { // RFC7540#6.5.2
error = H2_ERR_PROTOCOL_ERROR;
goto fail;
}
h2c->mfs = arg;
break;
case H2_SETTINGS_ENABLE_PUSH:
if (arg < 0 || arg > 1) { // RFC7540#6.5.2
error = H2_ERR_PROTOCOL_ERROR;
goto fail;
}
break;
}
}
/* need to ACK this frame now */
h2c->st0 = H2_CS_FRAME_A;
return 1;
fail:
h2c_error(h2c, error);
return 0;
}
/* try to send an ACK for a settings frame on the connection. Returns > 0 on
* success or one of the h2_status values.
*/
static int h2c_ack_settings(struct h2c *h2c)
{
struct buffer *res;
char str[9];
int ret = -1;
if (h2c_mux_busy(h2c, NULL)) {
h2c->flags |= H2_CF_DEM_MBUSY;
return 0;
}
res = h2_get_buf(h2c, &h2c->mbuf);
if (!res) {
h2c->flags |= H2_CF_MUX_MALLOC;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
memcpy(str,
"\x00\x00\x00" /* length : 0 (no data) */
"\x04" "\x01" /* type : 4, flags : ACK */
"\x00\x00\x00\x00" /* stream ID */, 9);
ret = b_istput(res, ist2(str, 9));
if (unlikely(ret <= 0)) {
if (!ret) {
h2c->flags |= H2_CF_MUX_MFULL;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
else {
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
return 0;
}
}
return ret;
}
/* processes a PING frame and schedules an ACK if needed. The caller must pass
* the pointer to the payload in <payload>. Returns > 0 on success or zero on
* missing data. It may return an error in h2c.
*/
static int h2c_handle_ping(struct h2c *h2c)
{
/* frame length must be exactly 8 */
if (h2c->dfl != 8) {
h2c_error(h2c, H2_ERR_FRAME_SIZE_ERROR);
return 0;
}
/* schedule a response */
if (!(h2c->dff & H2_F_PING_ACK))
h2c->st0 = H2_CS_FRAME_A;
return 1;
}
/* Try to send a window update for stream id <sid> and value <increment>.
* Returns > 0 on success or zero on missing room or failure. It may return an
* error in h2c.
*/
static int h2c_send_window_update(struct h2c *h2c, int sid, uint32_t increment)
{
struct buffer *res;
char str[13];
int ret = -1;
if (h2c_mux_busy(h2c, NULL)) {
h2c->flags |= H2_CF_DEM_MBUSY;
return 0;
}
res = h2_get_buf(h2c, &h2c->mbuf);
if (!res) {
h2c->flags |= H2_CF_MUX_MALLOC;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
/* length: 4, type: 8, flags: none */
memcpy(str, "\x00\x00\x04\x08\x00", 5);
write_n32(str + 5, sid);
write_n32(str + 9, increment);
ret = b_istput(res, ist2(str, 13));
if (unlikely(ret <= 0)) {
if (!ret) {
h2c->flags |= H2_CF_MUX_MFULL;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
else {
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
return 0;
}
}
return ret;
}
/* try to send pending window update for the connection. It's safe to call it
* with no pending updates. Returns > 0 on success or zero on missing room or
* failure. It may return an error in h2c.
*/
static int h2c_send_conn_wu(struct h2c *h2c)
{
int ret = 1;
if (h2c->rcvd_c <= 0)
return 1;
/* send WU for the connection */
ret = h2c_send_window_update(h2c, 0, h2c->rcvd_c);
if (ret > 0)
h2c->rcvd_c = 0;
return ret;
}
/* try to send pending window update for the current dmux stream. It's safe to
* call it with no pending updates. Returns > 0 on success or zero on missing
* room or failure. It may return an error in h2c.
*/
static int h2c_send_strm_wu(struct h2c *h2c)
{
int ret = 1;
if (h2c->rcvd_s <= 0)
return 1;
/* send WU for the stream */
ret = h2c_send_window_update(h2c, h2c->dsi, h2c->rcvd_s);
if (ret > 0)
h2c->rcvd_s = 0;
return ret;
}
/* try to send an ACK for a ping frame on the connection. Returns > 0 on
* success, 0 on missing data or one of the h2_status values.
*/
static int h2c_ack_ping(struct h2c *h2c)
{
struct buffer *res;
char str[17];
int ret = -1;
if (b_data(&h2c->dbuf) < 8)
return 0;
if (h2c_mux_busy(h2c, NULL)) {
h2c->flags |= H2_CF_DEM_MBUSY;
return 0;
}
res = h2_get_buf(h2c, &h2c->mbuf);
if (!res) {
h2c->flags |= H2_CF_MUX_MALLOC;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
memcpy(str,
"\x00\x00\x08" /* length : 8 (same payload) */
"\x06" "\x01" /* type : 6, flags : ACK */
"\x00\x00\x00\x00" /* stream ID */, 9);
/* copy the original payload */
h2_get_buf_bytes(str + 9, 8, &h2c->dbuf, 0);
ret = b_istput(res, ist2(str, 17));
if (unlikely(ret <= 0)) {
if (!ret) {
h2c->flags |= H2_CF_MUX_MFULL;
h2c->flags |= H2_CF_DEM_MROOM;
return 0;
}
else {
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
return 0;
}
}
return ret;
}
/* processes a WINDOW_UPDATE frame whose payload is <payload> for <plen> bytes.
* Returns > 0 on success or zero on missing data. It may return an error in
* h2c or h2s. Described in RFC7540#6.9.
*/
static int h2c_handle_window_update(struct h2c *h2c, struct h2s *h2s)
{
int32_t inc;
int error;
if (h2c->dfl != 4) {
error = H2_ERR_FRAME_SIZE_ERROR;
goto conn_err;
}
/* process full frame only */
if (b_data(&h2c->dbuf) < h2c->dfl)
return 0;
inc = h2_get_n32(&h2c->dbuf, 0);
if (h2c->dsi != 0) {
/* stream window update */
/* it's not an error to receive WU on a closed stream */
if (h2s->st == H2_SS_CLOSED)
return 1;
if (!inc) {
error = H2_ERR_PROTOCOL_ERROR;
goto strm_err;
}
if (h2s->mws >= 0 && h2s->mws + inc < 0) {
error = H2_ERR_FLOW_CONTROL_ERROR;
goto strm_err;
}
h2s->mws += inc;
if (h2s->mws > 0 && (h2s->flags & H2_SF_BLK_SFCTL)) {
h2s->flags &= ~H2_SF_BLK_SFCTL;
if (h2s->cs && LIST_ISEMPTY(&h2s->list) &&
(h2s->cs->flags & CS_FL_DATA_WR_ENA)) {
/* This stream wanted to send but could not due to its
* own flow control. We can put it back into the send
* list now, it will be handled upon next send() call.
*/
LIST_ADDQ(&h2c->send_list, &h2s->list);
}
}
}
else {
/* connection window update */
if (!inc) {
error = H2_ERR_PROTOCOL_ERROR;
goto conn_err;
}
if (h2c->mws >= 0 && h2c->mws + inc < 0) {
error = H2_ERR_FLOW_CONTROL_ERROR;
goto conn_err;
}
h2c->mws += inc;
}
return 1;
conn_err:
h2c_error(h2c, error);
return 0;
strm_err:
if (h2s) {
h2s_error(h2s, error);
h2c->st0 = H2_CS_FRAME_E;
}
else
h2c_error(h2c, error);
return 0;
}
/* processes a GOAWAY frame, and signals all streams whose ID is greater than
* the last ID. Returns > 0 on success or zero on missing data. It may return
* an error in h2c. Described in RFC7540#6.8.
*/
static int h2c_handle_goaway(struct h2c *h2c)
{
int error;
int last;
if (h2c->dsi != 0) {
error = H2_ERR_PROTOCOL_ERROR;
goto conn_err;
}
if (h2c->dfl < 8) {
error = H2_ERR_FRAME_SIZE_ERROR;
goto conn_err;
}
/* process full frame only */
if (b_data(&h2c->dbuf) < h2c->dfl)
return 0;
last = h2_get_n32(&h2c->dbuf, 0);
h2c->errcode = h2_get_n32(&h2c->dbuf, 4);
h2_wake_some_streams(h2c, last, CS_FL_ERROR);
if (h2c->last_sid < 0)
h2c->last_sid = last;
return 1;
conn_err:
h2c_error(h2c, error);
return 0;
}
/* processes a PRIORITY frame, and either skips it or rejects if it is
* invalid. Returns > 0 on success or zero on missing data. It may return
* an error in h2c. Described in RFC7540#6.3.
*/
static int h2c_handle_priority(struct h2c *h2c)
{
int error;
if (h2c->dsi == 0) {
error = H2_ERR_PROTOCOL_ERROR;
goto conn_err;
}
if (h2c->dfl != 5) {
error = H2_ERR_FRAME_SIZE_ERROR;
goto conn_err;
}
/* process full frame only */
if (b_data(&h2c->dbuf) < h2c->dfl)
return 0;
if (h2_get_n32(&h2c->dbuf, 0) == h2c->dsi) {
/* 7540#5.3 : can't depend on itself */
error = H2_ERR_PROTOCOL_ERROR;
goto conn_err;
}
return 1;
conn_err:
h2c_error(h2c, error);
return 0;
}
/* processes an RST_STREAM frame, and sets the 32-bit error code on the stream.
* Returns > 0 on success or zero on missing data. It may return an error in
* h2c. Described in RFC7540#6.4.
*/
static int h2c_handle_rst_stream(struct h2c *h2c, struct h2s *h2s)
{
int error;
if (h2c->dsi == 0) {
error = H2_ERR_PROTOCOL_ERROR;
goto conn_err;
}
if (h2c->dfl != 4) {
error = H2_ERR_FRAME_SIZE_ERROR;
goto conn_err;
}
/* process full frame only */
if (b_data(&h2c->dbuf) < h2c->dfl)
return 0;
/* late RST, already handled */
if (h2s->st == H2_SS_CLOSED)
return 1;
h2s->errcode = h2_get_n32(&h2c->dbuf, 0);
h2s_close(h2s);
if (h2s->cs) {
h2s->cs->flags |= CS_FL_EOS | CS_FL_ERROR;
h2s->cs->data_cb->wake(h2s->cs);
}
h2s->flags |= H2_SF_RST_RCVD;
return 1;
conn_err:
h2c_error(h2c, error);
return 0;
}
/* processes a HEADERS frame. Returns h2s on success or NULL on missing data.
* It may return an error in h2c or h2s. The caller must consider that the
* return value is the new h2s in case one was allocated (most common case).
* Described in RFC7540#6.2. Most of the
* errors here are reported as connection errors since it's impossible to
* recover from such errors after the compression context has been altered.
*/
static struct h2s *h2c_frt_handle_headers(struct h2c *h2c, struct h2s *h2s)
{
int error;
if (!h2c->dfl) {
error = H2_ERR_PROTOCOL_ERROR; // empty headers frame!
goto strm_err;
}
if (!b_size(&h2c->dbuf))
return NULL; // empty buffer
if (b_data(&h2c->dbuf) < h2c->dfl && !b_full(&h2c->dbuf))
return NULL; // incomplete frame
if (h2c->flags & H2_CF_DEM_TOOMANY)
return 0; // too many cs still present
/* now either the frame is complete or the buffer is complete */
if (h2s->st != H2_SS_IDLE) {
/* FIXME: stream already exists, this is only allowed for
* trailers (not supported for now).
*/
error = H2_ERR_PROTOCOL_ERROR;
goto conn_err;
}
else if (h2c->dsi <= h2c->max_id || !(h2c->dsi & 1)) {
/* RFC7540#5.1.1 stream id > prev ones, and must be odd here */
error = H2_ERR_PROTOCOL_ERROR;
goto conn_err;
}
h2s = h2c_stream_new(h2c, h2c->dsi);
if (!h2s) {
error = H2_ERR_INTERNAL_ERROR;
goto conn_err;
}
h2s->st = H2_SS_OPEN;
if (h2c->dff & H2_F_HEADERS_END_STREAM) {
h2s->st = H2_SS_HREM;
h2s->flags |= H2_SF_ES_RCVD;
/* note: cs cannot be null for now (just created above) */
h2s->cs->flags |= CS_FL_REOS;
}
if (!h2_frt_decode_headers(h2s))
return NULL;
if (h2c->st0 >= H2_CS_ERROR)
return NULL;
if (h2s->st >= H2_SS_ERROR) {
/* stream error : send RST_STREAM */
h2c->st0 = H2_CS_FRAME_E;
}
else {
/* update the max stream ID if the request is being processed */
if (h2s->id > h2c->max_id)
h2c->max_id = h2s->id;
}
return h2s;
conn_err:
h2c_error(h2c, error);
return NULL;
strm_err:
if (h2s) {
h2s_error(h2s, error);
h2c->st0 = H2_CS_FRAME_E;
}
else
h2c_error(h2c, error);
return NULL;
}
/* processes a DATA frame. Returns > 0 on success or zero on missing data.
* It may return an error in h2c or h2s. Described in RFC7540#6.1.
*/
static int h2c_frt_handle_data(struct h2c *h2c, struct h2s *h2s)
{
int error;
/* note that empty DATA frames are perfectly valid and sometimes used
* to signal an end of stream (with the ES flag).
*/
if (!b_size(&h2c->dbuf) && h2c->dfl)
return 0; // empty buffer
if (b_data(&h2c->dbuf) < h2c->dfl && !b_full(&h2c->dbuf))
return 0; // incomplete frame
/* now either the frame is complete or the buffer is complete */
if (!h2c->dsi) {
/* RFC7540#6.1 */
error = H2_ERR_PROTOCOL_ERROR;
goto conn_err;
}
if (h2s->st != H2_SS_OPEN && h2s->st != H2_SS_HLOC) {
/* RFC7540#6.1 */
error = H2_ERR_STREAM_CLOSED;
goto strm_err;
}
if (!h2_frt_transfer_data(h2s))
return 0;
/* call the upper layers to process the frame, then let the upper layer
* notify the stream about any change.
*/
if (!h2s->cs) {
error = H2_ERR_STREAM_CLOSED;
goto strm_err;
}
if (h2c->st0 >= H2_CS_ERROR)
return 0;
if (h2s->st >= H2_SS_ERROR) {
/* stream error : send RST_STREAM */
h2c->st0 = H2_CS_FRAME_E;
}
/* check for completion : the callee will change this to FRAME_A or
* FRAME_H once done.
*/
if (h2c->st0 == H2_CS_FRAME_P)
return 0;
/* last frame */
if (h2c->dff & H2_F_DATA_END_STREAM) {
h2s->st = H2_SS_HREM;
h2s->flags |= H2_SF_ES_RCVD;
h2s->cs->flags |= CS_FL_REOS;
}
return 1;
conn_err:
h2c_error(h2c, error);
return 0;
strm_err:
if (h2s) {
h2s_error(h2s, error);
h2c->st0 = H2_CS_FRAME_E;
}
else
h2c_error(h2c, error);
return 0;
}
/* process Rx frames to be demultiplexed */
static void h2_process_demux(struct h2c *h2c)
{
struct h2s *h2s = NULL, *tmp_h2s;
if (h2c->st0 >= H2_CS_ERROR)
return;
if (unlikely(h2c->st0 < H2_CS_FRAME_H)) {
if (h2c->st0 == H2_CS_PREFACE) {
if (unlikely(h2c_frt_recv_preface(h2c) <= 0)) {
/* RFC7540#3.5: a GOAWAY frame MAY be omitted */
if (h2c->st0 == H2_CS_ERROR)
h2c->st0 = H2_CS_ERROR2;
goto fail;
}
h2c->max_id = 0;
h2c->st0 = H2_CS_SETTINGS1;
}
if (h2c->st0 == H2_CS_SETTINGS1) {
struct h2_fh hdr;
/* ensure that what is pending is a valid SETTINGS frame
* without an ACK.
*/
if (!h2_get_frame_hdr(&h2c->dbuf, &hdr)) {
/* RFC7540#3.5: a GOAWAY frame MAY be omitted */
if (h2c->st0 == H2_CS_ERROR)
h2c->st0 = H2_CS_ERROR2;
goto fail;
}
if (hdr.sid || hdr.ft != H2_FT_SETTINGS || hdr.ff & H2_F_SETTINGS_ACK) {
/* RFC7540#3.5: a GOAWAY frame MAY be omitted */
h2c_error(h2c, H2_ERR_PROTOCOL_ERROR);
h2c->st0 = H2_CS_ERROR2;
goto fail;
}
if ((int)hdr.len < 0 || (int)hdr.len > global.tune.bufsize) {
/* RFC7540#3.5: a GOAWAY frame MAY be omitted */
h2c_error(h2c, H2_ERR_FRAME_SIZE_ERROR);
h2c->st0 = H2_CS_ERROR2;
goto fail;
}
/* that's OK, switch to FRAME_P to process it */
h2c->dfl = hdr.len;
h2c->dsi = hdr.sid;
h2c->dft = hdr.ft;
h2c->dff = hdr.ff;
h2c->dpl = 0;
h2c->st0 = H2_CS_FRAME_P;
}
}
/* process as many incoming frames as possible below */
while (b_data(&h2c->dbuf)) {
int ret = 0;
if (h2c->st0 >= H2_CS_ERROR)
break;
if (h2c->st0 == H2_CS_FRAME_H) {
struct h2_fh hdr;
if (!h2_peek_frame_hdr(&h2c->dbuf, &hdr))
break;
if ((int)hdr.len < 0 || (int)hdr.len > global.tune.bufsize) {
h2c_error(h2c, H2_ERR_FRAME_SIZE_ERROR);
h2c->st0 = H2_CS_ERROR;
break;
}
h2c->dfl = hdr.len;
h2c->dsi = hdr.sid;
h2c->dft = hdr.ft;
h2c->dff = hdr.ff;
h2c->dpl = 0;
h2c->st0 = H2_CS_FRAME_P;
h2_skip_frame_hdr(&h2c->dbuf);
}
/* Only H2_CS_FRAME_P and H2_CS_FRAME_A here */
tmp_h2s = h2c_st_by_id(h2c, h2c->dsi);
if (tmp_h2s != h2s && h2s && h2s->cs && b_data(&h2s->cs->rxbuf)) {
/* we may have to signal the upper layers */
h2s->cs->flags |= CS_FL_RCV_MORE;
if (h2s->cs->data_cb->wake(h2s->cs) < 0) {
/* cs has just been destroyed, we have to kill h2s. */
h2s_error(h2s, H2_ERR_STREAM_CLOSED);
goto strm_err;
}
if (h2c->st0 >= H2_CS_ERROR)
goto strm_err;
if (h2s->st >= H2_SS_ERROR) {
/* stream error : send RST_STREAM */
h2c->st0 = H2_CS_FRAME_E;
}
}
h2s = tmp_h2s;
if (h2c->st0 == H2_CS_FRAME_E)
goto strm_err;
if (h2s->st == H2_SS_IDLE &&
h2c->dft != H2_FT_HEADERS && h2c->dft != H2_FT_PRIORITY) {
/* RFC7540#5.1: any frame other than HEADERS or PRIORITY in
* this state MUST be treated as a connection error
*/
h2c_error(h2c, H2_ERR_PROTOCOL_ERROR);
h2c->st0 = H2_CS_ERROR;
break;
}
if (h2s->st == H2_SS_HREM && h2c->dft != H2_FT_WINDOW_UPDATE &&
h2c->dft != H2_FT_RST_STREAM && h2c->dft != H2_FT_PRIORITY) {
/* RFC7540#5.1: any frame other than WU/PRIO/RST in
* this state MUST be treated as a stream error
*/
h2s_error(h2s, H2_ERR_STREAM_CLOSED);
goto strm_err;
}
/* Below the management of frames received in closed state is a
* bit hackish because the spec makes strong differences between
* streams closed by receiving RST, sending RST, and seeing ES
* in both directions. In addition to this, the creation of a
* new stream reusing the identifier of a closed one will be
* detected here. Given that we cannot keep track of all closed
* streams forever, we consider that unknown closed streams were
* closed on RST received, which allows us to respond with an
* RST without breaking the connection (eg: to abort a transfer).
* Some frames have to be silently ignored as well.
*/
if (h2s->st == H2_SS_CLOSED && h2c->dsi) {
if (h2c->dft == H2_FT_HEADERS || h2c->dft == H2_FT_PUSH_PROMISE) {
/* #5.1.1: The identifier of a newly
* established stream MUST be numerically
* greater than all streams that the initiating
* endpoint has opened or reserved. This
* governs streams that are opened using a
* HEADERS frame and streams that are reserved
* using PUSH_PROMISE. An endpoint that
* receives an unexpected stream identifier
* MUST respond with a connection error.
*/
h2c_error(h2c, H2_ERR_STREAM_CLOSED);
goto strm_err;
}
if (h2s->flags & H2_SF_RST_RCVD) {
/* RFC7540#5.1:closed: an endpoint that
* receives any frame other than PRIORITY after
* receiving a RST_STREAM MUST treat that as a
* stream error of type STREAM_CLOSED.
*
* Note that old streams fall into this category
* and will lead to an RST being sent.
*/
h2s_error(h2s, H2_ERR_STREAM_CLOSED);
h2c->st0 = H2_CS_FRAME_E;
goto strm_err;
}
/* RFC7540#5.1:closed: if this state is reached as a
* result of sending a RST_STREAM frame, the peer that
* receives the RST_STREAM might have already sent
* frames on the stream that cannot be withdrawn. An
* endpoint MUST ignore frames that it receives on
* closed streams after it has sent a RST_STREAM
* frame. An endpoint MAY choose to limit the period
* over which it ignores frames and treat frames that
* arrive after this time as being in error.
*/
if (!(h2s->flags & H2_SF_RST_SENT)) {
/* RFC7540#5.1:closed: any frame other than
* PRIO/WU/RST in this state MUST be treated as
* a connection error
*/
if (h2c->dft != H2_FT_RST_STREAM &&
h2c->dft != H2_FT_PRIORITY &&
h2c->dft != H2_FT_WINDOW_UPDATE) {
h2c_error(h2c, H2_ERR_STREAM_CLOSED);
goto strm_err;
}
}
}
#if 0
// problem below: it is not possible to completely ignore such
// streams as we need to maintain the compression state as well
// and for this we need to completely process these frames (eg:
// HEADERS frames) as well as counting DATA frames to emit
// proper WINDOW UPDATES and ensure the connection doesn't stall.
// This is a typical case of layer violation where the
// transported contents are critical to the connection's
// validity and must be ignored at the same time :-(
/* graceful shutdown, ignore streams whose ID is higher than
* the one advertised in GOAWAY. RFC7540#6.8.
*/
if (unlikely(h2c->last_sid >= 0) && h2c->dsi > h2c->last_sid) {
ret = MIN(b_data(&h2c->dbuf), h2c->dfl);
b_del(&h2c->dbuf, ret);
h2c->dfl -= ret;
ret = h2c->dfl == 0;
goto strm_err;
}
#endif
switch (h2c->dft) {
case H2_FT_SETTINGS:
if (h2c->st0 == H2_CS_FRAME_P)
ret = h2c_handle_settings(h2c);
if (h2c->st0 == H2_CS_FRAME_A)
ret = h2c_ack_settings(h2c);
break;
case H2_FT_PING:
if (h2c->st0 == H2_CS_FRAME_P)
ret = h2c_handle_ping(h2c);
if (h2c->st0 == H2_CS_FRAME_A)
ret = h2c_ack_ping(h2c);
break;
case H2_FT_WINDOW_UPDATE:
if (h2c->st0 == H2_CS_FRAME_P)
ret = h2c_handle_window_update(h2c, h2s);
break;
case H2_FT_CONTINUATION:
/* we currently don't support CONTINUATION frames since
* we have nowhere to store the partial HEADERS frame.
* Let's abort the stream on an INTERNAL_ERROR here.
*/
if (h2c->st0 == H2_CS_FRAME_P) {
h2s_error(h2s, H2_ERR_INTERNAL_ERROR);
h2c->st0 = H2_CS_FRAME_E;
}
break;
case H2_FT_HEADERS:
if (h2c->st0 == H2_CS_FRAME_P) {
tmp_h2s = h2c_frt_handle_headers(h2c, h2s);
if (tmp_h2s) {
h2s = tmp_h2s;
ret = 1;
}
}
break;
case H2_FT_DATA:
if (h2c->st0 == H2_CS_FRAME_P)
ret = h2c_frt_handle_data(h2c, h2s);
if (h2c->st0 == H2_CS_FRAME_A)
ret = h2c_send_strm_wu(h2c);
break;
case H2_FT_PRIORITY:
if (h2c->st0 == H2_CS_FRAME_P)
ret = h2c_handle_priority(h2c);
break;
case H2_FT_RST_STREAM:
if (h2c->st0 == H2_CS_FRAME_P)
ret = h2c_handle_rst_stream(h2c, h2s);
break;
case H2_FT_GOAWAY:
if (h2c->st0 == H2_CS_FRAME_P)
ret = h2c_handle_goaway(h2c);
break;
case H2_FT_PUSH_PROMISE:
/* not permitted here, RFC7540#5.1 */
h2c_error(h2c, H2_ERR_PROTOCOL_ERROR);
break;
/* implement all extra frame types here */
default:
/* drop frames that we ignore. They may be larger than
* the buffer so we drain all of their contents until
* we reach the end.
*/
ret = MIN(b_data(&h2c->dbuf), h2c->dfl);
b_del(&h2c->dbuf, ret);
h2c->dfl -= ret;
ret = h2c->dfl == 0;
}
strm_err:
/* We may have to send an RST if not done yet */
if (h2s->st == H2_SS_ERROR)
h2c->st0 = H2_CS_FRAME_E;
if (h2c->st0 == H2_CS_FRAME_E)
ret = h2c_send_rst_stream(h2c, h2s);
/* error or missing data condition met above ? */
if (ret <= 0) {
h2s = NULL;
break;
}
if (h2c->st0 != H2_CS_FRAME_H) {
b_del(&h2c->dbuf, h2c->dfl);
h2c->st0 = H2_CS_FRAME_H;
}
}
if (h2c->rcvd_c > 0 &&
!(h2c->flags & (H2_CF_MUX_MFULL | H2_CF_DEM_MBUSY | H2_CF_DEM_MROOM)))
h2c_send_conn_wu(h2c);
fail:
/* we can go here on missing data, blocked response or error */
if (h2s && h2s->cs && b_data(&h2s->cs->rxbuf)) {
/* we may have to signal the upper layers */
h2s->cs->flags |= CS_FL_RCV_MORE;
if (h2s->cs->data_cb->wake(h2s->cs) < 0) {
/* cs has just been destroyed, we have to kill h2s. */
h2s_error(h2s, H2_ERR_STREAM_CLOSED);
h2c_send_rst_stream(h2c, h2s);
}
}
return;
}
/* process Tx frames from streams to be multiplexed. Returns > 0 if it reached
* the end.
*/
static int h2_process_mux(struct h2c *h2c)
{
struct h2s *h2s, *h2s_back;
/* start by sending possibly pending window updates */
if (h2c->rcvd_c > 0 &&
!(h2c->flags & (H2_CF_MUX_MFULL | H2_CF_MUX_MALLOC)) &&
h2c_send_conn_wu(h2c) < 0)
goto fail;
/* First we always process the flow control list because the streams
* waiting there were already elected for immediate emission but were
* blocked just on this.
*/
list_for_each_entry_safe(h2s, h2s_back, &h2c->fctl_list, list) {
if (h2c->mws <= 0 || h2c->flags & H2_CF_MUX_BLOCK_ANY ||
h2c->st0 >= H2_CS_ERROR)
break;
/* In theory it's possible that h2s->cs == NULL here :
* - client sends crap that causes a parse error
* - RST_STREAM is produced and CS_FL_ERROR at the same time
* - RST_STREAM cannot be emitted because mux is busy/full
* - stream gets notified, detaches and quits
* - mux buffer gets ready and wakes pending streams up
* - bam!
*/
h2s->flags &= ~H2_SF_BLK_ANY;
if (h2s->cs) {
h2s->cs->data_cb->wake(h2s->cs);
} else {
h2s_send_rst_stream(h2c, h2s);
}
/* depending on callee's blocking reasons, we may queue in send
* list or completely dequeue.
*/
if ((h2s->flags & H2_SF_BLK_MFCTL) == 0) {
if (h2s->flags & H2_SF_BLK_ANY) {
LIST_DEL(&h2s->list);
LIST_ADDQ(&h2c->send_list, &h2s->list);
}
else {
LIST_DEL(&h2s->list);
LIST_INIT(&h2s->list);
if (h2s->cs)
h2s->cs->flags &= ~CS_FL_DATA_WR_ENA;
else {
/* just sent the last frame for this orphaned stream */
h2s_destroy(h2s);
}
}
}
}
list_for_each_entry_safe(h2s, h2s_back, &h2c->send_list, list) {
if (h2c->st0 >= H2_CS_ERROR || h2c->flags & H2_CF_MUX_BLOCK_ANY)
break;
/* In theory it's possible that h2s->cs == NULL here :
* - client sends crap that causes a parse error
* - RST_STREAM is produced and CS_FL_ERROR at the same time
* - RST_STREAM cannot be emitted because mux is busy/full
* - stream gets notified, detaches and quits
* - mux buffer gets ready and wakes pending streams up
* - bam!
*/
h2s->flags &= ~H2_SF_BLK_ANY;
if (h2s->cs) {
h2s->cs->data_cb->wake(h2s->cs);
} else {
h2s_send_rst_stream(h2c, h2s);
}
/* depending on callee's blocking reasons, we may queue in fctl
* list or completely dequeue.
*/
if (h2s->flags & H2_SF_BLK_MFCTL) {
/* stream hit the connection's flow control */
LIST_DEL(&h2s->list);
LIST_ADDQ(&h2c->fctl_list, &h2s->list);
}
else if (!(h2s->flags & H2_SF_BLK_ANY)) {
LIST_DEL(&h2s->list);
LIST_INIT(&h2s->list);
if (h2s->cs)
h2s->cs->flags &= ~CS_FL_DATA_WR_ENA;
else {
/* just sent the last frame for this orphaned stream */
h2s_destroy(h2s);
}
}
}
fail:
if (unlikely(h2c->st0 >= H2_CS_ERROR)) {
if (h2c->st0 == H2_CS_ERROR) {
if (h2c->max_id >= 0) {
h2c_send_goaway_error(h2c, NULL);
if (h2c->flags & H2_CF_MUX_BLOCK_ANY)
return 0;
}
h2c->st0 = H2_CS_ERROR2; // sent (or failed hard) !
}
return 1;
}
return (h2c->mws <= 0 || LIST_ISEMPTY(&h2c->fctl_list)) && LIST_ISEMPTY(&h2c->send_list);
}
/*********************************************************/
/* functions below are I/O callbacks from the connection */
/*********************************************************/
/* callback called on recv event by the connection handler */
static void h2_recv(struct connection *conn)
{
struct h2c *h2c = conn->mux_ctx;
struct buffer *buf;
int max;
if (!h2_recv_allowed(h2c))
return;
buf = h2_get_buf(h2c, &h2c->dbuf);
if (!buf) {
h2c->flags |= H2_CF_DEM_DALLOC;
return;
}
max = buf->size - b_data(buf);
if (max)
conn->xprt->rcv_buf(conn, buf, max, 0);
if (!b_data(buf)) {
h2_release_buf(h2c, &h2c->dbuf);
return;
}
if (b_data(buf) == buf->size)
h2c->flags |= H2_CF_DEM_DFULL;
return;
}
/* Try to send data if possible */
static struct task *h2_send(struct task *t, void *ctx, unsigned short state)
{
struct connection *conn = ctx;
struct h2c *h2c = conn->mux_ctx;
int done;
if (conn->flags & CO_FL_ERROR)
return NULL;
if (conn->flags & (CO_FL_HANDSHAKE|CO_FL_WAIT_L4_CONN|CO_FL_WAIT_L6_CONN)) {
/* a handshake was requested */
return NULL;
}
/* This loop is quite simple : it tries to fill as much as it can from
* pending streams into the existing buffer until it's reportedly full
* or the end of send requests is reached. Then it tries to send this
* buffer's contents out, marks it not full if at least one byte could
* be sent, and tries again.
*
* The snd_buf() function normally takes a "flags" argument which may
* be made of a combination of CO_SFL_MSG_MORE to indicate that more
* data immediately comes and CO_SFL_STREAMER to indicate that the
* connection is streaming lots of data (used to increase TLS record
* size at the expense of latency). The former can be sent any time
* there's a buffer full flag, as it indicates at least one stream
* attempted to send and failed so there are pending data. An
* alternative would be to set it as long as there's an active stream
* but that would be problematic for ACKs until we have an absolute
* guarantee that all waiters have at least one byte to send. The
* latter should possibly not be set for now.
*/
done = 0;
while (!done) {
unsigned int flags = 0;
/* fill as much as we can into the current buffer */
while (((h2c->flags & (H2_CF_MUX_MFULL|H2_CF_MUX_MALLOC)) == 0) && !done)
done = h2_process_mux(h2c);
if (conn->flags & CO_FL_ERROR)
break;
if (h2c->flags & (H2_CF_MUX_MFULL | H2_CF_DEM_MBUSY | H2_CF_DEM_MROOM))
flags |= CO_SFL_MSG_MORE;
if (b_data(&h2c->mbuf)) {
int ret = conn->xprt->snd_buf(conn, &h2c->mbuf, b_data(&h2c->mbuf), flags);
if (!ret)
break;
b_del(&h2c->mbuf, ret);
b_realign_if_empty(&h2c->mbuf);
}
/* wrote at least one byte, the buffer is not full anymore */
h2c->flags &= ~(H2_CF_MUX_MFULL | H2_CF_DEM_MROOM);
}
if (conn->flags & CO_FL_SOCK_WR_SH) {
/* output closed, nothing to send, clear the buffer to release it */
b_reset(&h2c->mbuf);
}
/* We're not full anymore, so we can wake any task that are waiting
* for us.
*/
if (!(h2c->flags & (H2_CF_MUX_MFULL | H2_CF_DEM_MROOM))) {
while (!LIST_ISEMPTY(&h2c->send_wait_list)) {
struct wait_list *sw = LIST_ELEM(h2c->send_wait_list.n,
struct wait_list *, list);
LIST_DEL(&sw->list);
LIST_INIT(&sw->list);
tasklet_wakeup(sw->task);
}
}
/* We're done, no more to send */
if (!b_data(&h2c->mbuf))
return NULL;
schedule:
if (LIST_ISEMPTY(&h2c->wait_list.list))
conn->xprt->subscribe(conn, SUB_CAN_SEND, &h2c->wait_list);
return NULL;
}
/* callback called on any event by the connection handler.
* It applies changes and returns zero, or < 0 if it wants immediate
* destruction of the connection (which normally doesn not happen in h2).
*/
static int h2_wake(struct connection *conn)
{
struct h2c *h2c = conn->mux_ctx;
struct session *sess = conn->owner;
h2_send(NULL, conn, 0);
if (b_data(&h2c->dbuf) && !(h2c->flags & H2_CF_DEM_BLOCK_ANY)) {
h2_process_demux(h2c);
if (h2c->st0 >= H2_CS_ERROR || conn->flags & CO_FL_ERROR)
b_reset(&h2c->dbuf);
if (!b_full(&h2c->dbuf))
h2c->flags &= ~H2_CF_DEM_DFULL;
}
if (sess && unlikely(sess->fe->state == PR_STSTOPPED)) {
/* frontend is stopping, reload likely in progress, let's try
* to announce a graceful shutdown if not yet done. We don't
* care if it fails, it will be tried again later.
*/
if (!(h2c->flags & (H2_CF_GOAWAY_SENT|H2_CF_GOAWAY_FAILED))) {
if (h2c->last_sid < 0)
h2c->last_sid = (1U << 31) - 1;
h2c_send_goaway_error(h2c, NULL);
}
}
/*
* If we received early data, and the handshake is done, wake
* any stream that was waiting for it.
*/
if (!(h2c->flags & H2_CF_WAIT_FOR_HS) &&
(conn->flags & (CO_FL_EARLY_SSL_HS | CO_FL_HANDSHAKE | CO_FL_EARLY_DATA)) == CO_FL_EARLY_DATA) {
struct eb32_node *node;
struct h2s *h2s;
h2c->flags |= H2_CF_WAIT_FOR_HS;
node = eb32_lookup_ge(&h2c->streams_by_id, 1);
while (node) {
h2s = container_of(node, struct h2s, by_id);
if (h2s->cs->flags & CS_FL_WAIT_FOR_HS)
h2s->cs->data_cb->wake(h2s->cs);
node = eb32_next(node);
}
}
if (conn->flags & CO_FL_ERROR || conn_xprt_read0_pending(conn) ||
h2c->st0 == H2_CS_ERROR2 || h2c->flags & H2_CF_GOAWAY_FAILED ||
(eb_is_empty(&h2c->streams_by_id) && h2c->last_sid >= 0 &&
h2c->max_id >= h2c->last_sid)) {
h2_wake_some_streams(h2c, 0, 0);
if (eb_is_empty(&h2c->streams_by_id)) {
/* no more stream, kill the connection now */
h2_release(conn);
return -1;
}
else {
/* some streams still there, we need to signal them all and
* wait for their departure.
*/
__conn_xprt_stop_recv(conn);
__conn_xprt_stop_send(conn);
return 0;
}
}
if (!b_data(&h2c->dbuf))
h2_release_buf(h2c, &h2c->dbuf);
/* stop being notified of incoming data if we can't process them */
if (!h2_recv_allowed(h2c)) {
__conn_xprt_stop_recv(conn);
}
else {
__conn_xprt_want_recv(conn);
}
/* adjust output polling */
if (!(conn->flags & CO_FL_SOCK_WR_SH) &&
(h2c->st0 == H2_CS_ERROR ||
b_data(&h2c->mbuf) ||
(h2c->mws > 0 && !LIST_ISEMPTY(&h2c->fctl_list)) ||
(!(h2c->flags & H2_CF_MUX_BLOCK_ANY) && !LIST_ISEMPTY(&h2c->send_list)))) {
__conn_xprt_want_send(conn);
}
else {
h2_release_buf(h2c, &h2c->mbuf);
__conn_xprt_stop_send(conn);
}
if (h2c->task) {
if (eb_is_empty(&h2c->streams_by_id) || b_data(&h2c->mbuf)) {
h2c->task->expire = tick_add(now_ms, h2c->last_sid < 0 ? h2c->timeout : h2c->shut_timeout);
task_queue(h2c->task);
}
else
h2c->task->expire = TICK_ETERNITY;
}
return 0;
}
/* Connection timeout management. The principle is that if there's no receipt
* nor sending for a certain amount of time, the connection is closed. If the
* MUX buffer still has lying data or is not allocatable, the connection is
* immediately killed. If it's allocatable and empty, we attempt to send a
* GOAWAY frame.
*/
static struct task *h2_timeout_task(struct task *t, void *context, unsigned short state)
{
struct h2c *h2c = context;
int expired = tick_is_expired(t->expire, now_ms);
if (!expired && h2c)
return t;
task_delete(t);
task_free(t);
if (!h2c) {
/* resources were already deleted */
return NULL;
}
h2c->task = NULL;
h2c_error(h2c, H2_ERR_NO_ERROR);
h2_wake_some_streams(h2c, 0, 0);
if (b_data(&h2c->mbuf)) {
/* don't even try to send a GOAWAY, the buffer is stuck */
h2c->flags |= H2_CF_GOAWAY_FAILED;
}
/* try to send but no need to insist */
h2c->last_sid = h2c->max_id;
if (h2c_send_goaway_error(h2c, NULL) <= 0)
h2c->flags |= H2_CF_GOAWAY_FAILED;
if (b_data(&h2c->mbuf) && !(h2c->flags & H2_CF_GOAWAY_FAILED) && conn_xprt_ready(h2c->conn)) {
int ret = h2c->conn->xprt->snd_buf(h2c->conn, &h2c->mbuf, b_data(&h2c->mbuf), 0);
if (ret > 0) {
b_del(&h2c->mbuf, ret);
b_realign_if_empty(&h2c->mbuf);
}
}
/* either we can release everything now or it will be done later once
* the last stream closes.
*/
if (eb_is_empty(&h2c->streams_by_id))
h2_release(h2c->conn);
return NULL;
}
/*******************************************/
/* functions below are used by the streams */
/*******************************************/
/*
* Attach a new stream to a connection
* (Used for outgoing connections)
*/
static struct conn_stream *h2_attach(struct connection *conn)
{
return NULL;
}
/* callback used to update the mux's polling flags after changing a cs' status.
* The caller (cs_update_mux_polling) will take care of propagating any changes
* to the transport layer.
*/
static void h2_update_poll(struct conn_stream *cs)
{
struct h2s *h2s = cs->ctx;
if (!h2s)
return;
/* we may unblock a blocked read */
if (cs->flags & CS_FL_DATA_RD_ENA) {
/* the stream indicates it's willing to read */
h2s->h2c->flags &= ~H2_CF_DEM_SFULL;
if (h2s->h2c->dsi == h2s->id) {
conn_xprt_want_recv(cs->conn);
conn_xprt_want_send(cs->conn);
}
}
/* Note: the stream and stream-int code doesn't allow us to perform a
* synchronous send() here unfortunately, because this code is called
* as si_update() from the process_stream() context. This means that
* we have to queue the current cs and defer its processing after the
* connection's cs list is processed anyway.
*/
if (cs->flags & CS_FL_DATA_WR_ENA) {
if (LIST_ISEMPTY(&h2s->list)) {
if (LIST_ISEMPTY(&h2s->h2c->send_list) &&
!b_data(&h2s->h2c->mbuf) && // not yet subscribed
!(cs->conn->flags & CO_FL_SOCK_WR_SH))
conn_xprt_want_send(cs->conn);
LIST_ADDQ(&h2s->h2c->send_list, &h2s->list);
}
}
else if (!LIST_ISEMPTY(&h2s->list)) {
LIST_DEL(&h2s->list);
LIST_INIT(&h2s->list);
h2s->flags &= ~(H2_SF_BLK_MBUSY | H2_SF_BLK_MROOM | H2_SF_BLK_MFCTL);
}
/* this can happen from within si_chk_snd() */
if (b_data(&h2s->h2c->mbuf) && !(cs->conn->flags & CO_FL_XPRT_WR_ENA))
conn_xprt_want_send(cs->conn);
}
/*
* Detach the stream from the connection and possibly release the connection.
*/
static void h2_detach(struct conn_stream *cs)
{
struct h2s *h2s = cs->ctx;
struct h2c *h2c;
cs->ctx = NULL;
if (!h2s)
return;
h2c = h2s->h2c;
h2s->cs = NULL;
h2c->nb_cs--;
if (h2c->flags & H2_CF_DEM_TOOMANY &&
!h2_has_too_many_cs(h2c)) {
h2c->flags &= ~H2_CF_DEM_TOOMANY;
if (h2_recv_allowed(h2c)) {
__conn_xprt_want_recv(h2c->conn);
conn_xprt_want_send(h2c->conn);
}
}
/* this stream may be blocked waiting for some data to leave (possibly
* an ES or RST frame), so orphan it in this case.
*/
if (!(cs->conn->flags & CO_FL_ERROR) &&
(h2s->flags & (H2_SF_BLK_MBUSY | H2_SF_BLK_MROOM | H2_SF_BLK_MFCTL)))
return;
if ((h2c->flags & H2_CF_DEM_BLOCK_ANY && h2s->id == h2c->dsi) ||
(h2c->flags & H2_CF_MUX_BLOCK_ANY && h2s->id == h2c->msi)) {
/* unblock the connection if it was blocked on this
* stream.
*/
h2c->flags &= ~H2_CF_DEM_BLOCK_ANY;
h2c->flags &= ~H2_CF_MUX_BLOCK_ANY;
conn_xprt_want_recv(cs->conn);
conn_xprt_want_send(cs->conn);
}
h2s_destroy(h2s);
/* We don't want to close right now unless we're removing the
* last stream, and either the connection is in error, or it
* reached the ID already specified in a GOAWAY frame received
* or sent (as seen by last_sid >= 0).
*/
if (eb_is_empty(&h2c->streams_by_id) && /* don't close if streams exist */
((h2c->conn->flags & CO_FL_ERROR) || /* errors close immediately */
(h2c->st0 >= H2_CS_ERROR && !h2c->task) || /* a timeout stroke earlier */
(h2c->flags & H2_CF_GOAWAY_FAILED) ||
(!b_data(&h2c->mbuf) && /* mux buffer empty, also process clean events below */
(conn_xprt_read0_pending(h2c->conn) ||
(h2c->last_sid >= 0 && h2c->max_id >= h2c->last_sid))))) {
/* no more stream will come, kill it now */
h2_release(h2c->conn);
}
else if (h2c->task) {
if (eb_is_empty(&h2c->streams_by_id) || b_data(&h2c->mbuf)) {
h2c->task->expire = tick_add(now_ms, h2c->last_sid < 0 ? h2c->timeout : h2c->shut_timeout);
task_queue(h2c->task);
}
else
h2c->task->expire = TICK_ETERNITY;
}
}
static void h2_shutr(struct conn_stream *cs, enum cs_shr_mode mode)
{
struct h2s *h2s = cs->ctx;
if (!mode)
return;
if (h2s->st == H2_SS_HLOC || h2s->st == H2_SS_ERROR || h2s->st == H2_SS_CLOSED)
return;
/* if no outgoing data was seen on this stream, it means it was
* closed with a "tcp-request content" rule that is normally
* used to kill the connection ASAP (eg: limit abuse). In this
* case we send a goaway to close the connection.
*/
if (!(h2s->flags & H2_SF_RST_SENT) &&
h2s_send_rst_stream(h2s->h2c, h2s) <= 0)
goto add_to_list;
if (!(h2s->flags & H2_SF_OUTGOING_DATA) &&
!(h2s->h2c->flags & (H2_CF_GOAWAY_SENT|H2_CF_GOAWAY_FAILED)) &&
h2c_send_goaway_error(h2s->h2c, h2s) <= 0)
goto add_to_list;
if (b_data(&h2s->h2c->mbuf) && !(cs->conn->flags & CO_FL_XPRT_WR_ENA))
conn_xprt_want_send(cs->conn);
h2s_close(h2s);
add_to_list:
if (LIST_ISEMPTY(&h2s->list)) {
if (h2s->flags & H2_SF_BLK_MFCTL)
LIST_ADDQ(&h2s->h2c->fctl_list, &h2s->list);
else if (h2s->flags & (H2_SF_BLK_MBUSY|H2_SF_BLK_MROOM))
LIST_ADDQ(&h2s->h2c->send_list, &h2s->list);
}
}
static void h2_shutw(struct conn_stream *cs, enum cs_shw_mode mode)
{
struct h2s *h2s = cs->ctx;
if (h2s->st == H2_SS_HLOC || h2s->st == H2_SS_ERROR || h2s->st == H2_SS_CLOSED)
return;
if (h2s->flags & H2_SF_HEADERS_SENT) {
/* we can cleanly close using an empty data frame only after headers */
if (!(h2s->flags & (H2_SF_ES_SENT|H2_SF_RST_SENT)) &&
h2_send_empty_data_es(h2s) <= 0)
goto add_to_list;
if (h2s->st == H2_SS_HREM)
h2s_close(h2s);
else
h2s->st = H2_SS_HLOC;
} else {
/* if no outgoing data was seen on this stream, it means it was
* closed with a "tcp-request content" rule that is normally
* used to kill the connection ASAP (eg: limit abuse). In this
* case we send a goaway to close the connection.
*/
if (!(h2s->flags & H2_SF_RST_SENT) &&
h2s_send_rst_stream(h2s->h2c, h2s) <= 0)
goto add_to_list;
if (!(h2s->flags & H2_SF_OUTGOING_DATA) &&
!(h2s->h2c->flags & (H2_CF_GOAWAY_SENT|H2_CF_GOAWAY_FAILED)) &&
h2c_send_goaway_error(h2s->h2c, h2s) <= 0)
goto add_to_list;
h2s_close(h2s);
}
if (b_data(&h2s->h2c->mbuf) && !(cs->conn->flags & CO_FL_XPRT_WR_ENA))
conn_xprt_want_send(cs->conn);
add_to_list:
if (LIST_ISEMPTY(&h2s->list)) {
if (h2s->flags & H2_SF_BLK_MFCTL)
LIST_ADDQ(&h2s->h2c->fctl_list, &h2s->list);
else if (h2s->flags & (H2_SF_BLK_MBUSY|H2_SF_BLK_MROOM))
LIST_ADDQ(&h2s->h2c->send_list, &h2s->list);
}
}
/* Decode the payload of a HEADERS frame and produce the equivalent HTTP/1
* request. Returns the number of bytes emitted if > 0, or 0 if it couldn't
* proceed. Stream errors are reported in h2s->errcode and connection errors
* in h2c->errcode.
*/
static int h2_frt_decode_headers(struct h2s *h2s)
{
struct h2c *h2c = h2s->h2c;
const uint8_t *hdrs = (uint8_t *)b_head(&h2c->dbuf);
struct buffer *tmp = get_trash_chunk();
struct http_hdr list[MAX_HTTP_HDR * 2];
struct buffer *copy = NULL;
unsigned int msgf;
struct buffer *csbuf;
int flen = h2c->dfl;
int outlen = 0;
int wrap;
int try;
if (!h2c->dfl) {
h2s_error(h2s, H2_ERR_PROTOCOL_ERROR); // empty headers frame!
h2c->st0 = H2_CS_FRAME_E;
return 0;
}
if (b_data(&h2c->dbuf) < h2c->dfl && !b_full(&h2c->dbuf))
return 0; // incomplete input frame
/* if the input buffer wraps, take a temporary copy of it (rare) */
wrap = b_wrap(&h2c->dbuf) - b_head(&h2c->dbuf);
if (wrap < h2c->dfl) {
copy = alloc_trash_chunk();
if (!copy) {
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
goto fail;
}
memcpy(copy->area, b_head(&h2c->dbuf), wrap);
memcpy(copy->area + wrap, b_orig(&h2c->dbuf), h2c->dfl - wrap);
hdrs = (uint8_t *) copy->area;
}
/* The padlen is the first byte before data, and the padding appears
* after data. padlen+data+padding are included in flen.
*/
if (h2c->dff & H2_F_HEADERS_PADDED) {
h2c->dpl = *hdrs;
if (h2c->dpl >= flen) {
/* RFC7540#6.2 : pad length = length of frame payload or greater */
h2c_error(h2c, H2_ERR_PROTOCOL_ERROR);
return 0;
}
flen -= h2c->dpl + 1;
hdrs += 1; // skip Pad Length
}
/* Skip StreamDep and weight for now (we don't support PRIORITY) */
if (h2c->dff & H2_F_HEADERS_PRIORITY) {
if (read_n32(hdrs) == h2s->id) {
/* RFC7540#5.3.1 : stream dep may not depend on itself */
h2c_error(h2c, H2_ERR_PROTOCOL_ERROR);
return 0;//goto fail_stream;
}
hdrs += 5; // stream dep = 4, weight = 1
flen -= 5;
}
/* FIXME: lack of END_HEADERS means there's a continuation frame, we
* don't support this for now and can't even decompress so we have to
* break the connection.
*/
if (!(h2c->dff & H2_F_HEADERS_END_HEADERS)) {
h2c_error(h2c, H2_ERR_INTERNAL_ERROR);
goto fail;
}
csbuf = h2_get_buf(h2c, &h2s->cs->rxbuf);
if (!csbuf) {
h2c->flags |= H2_CF_DEM_SALLOC;
goto fail;
}
/* we can't retry a failed decompression operation so we must be very
* careful not to take any risks. In practice the output buffer is
* always empty except maybe for trailers, in which case we simply have
* to wait for the upper layer to finish consuming what is available.
*/
if (b_data(csbuf))
goto fail;
csbuf->head = 0;
try = b_size(csbuf);
outlen = hpack_decode_frame(h2c->ddht, hdrs, flen, list,
sizeof(list)/sizeof(list[0]), tmp);
if (outlen < 0) {
h2c_error(h2c, H2_ERR_COMPRESSION_ERROR);
goto fail;
}
/* OK now we have our header list in <list> */
msgf = (h2c->dff & H2_F_DATA_END_STREAM) ? 0 : H2_MSGF_BODY;
outlen = h2_make_h1_request(list, b_tail(csbuf), try, &msgf);
if (outlen < 0) {
h2c_error(h2c, H2_ERR_COMPRESSION_ERROR);
goto fail;
}
if (msgf & H2_MSGF_BODY) {
/* a payload is present */
if (msgf & H2_MSGF_BODY_CL)
h2s->flags |= H2_SF_DATA_CLEN;
else if (!(msgf & H2_MSGF_BODY_TUNNEL))
h2s->flags |= H2_SF_DATA_CHNK;
}
/* now consume the input data */
b_del(&h2c->dbuf, h2c->dfl);
h2c->st0 = H2_CS_FRAME_H;
b_add(csbuf, outlen);
if (h2c->dff & H2_F_HEADERS_END_STREAM) {
h2s->flags |= H2_SF_ES_RCVD;
h2s->cs->flags |= CS_FL_REOS;
}
leave:
free_trash_chunk(copy);
return outlen;
fail:
outlen = 0;
goto leave;
}
/* Transfer the payload of a DATA frame to the HTTP/1 side. When content-length
* or a tunnel is used, the contents are copied as-is. When chunked encoding is
* in use, a new chunk is emitted for each frame. This is supposed to fit
* because the smallest chunk takes 1 byte for the size, 2 for CRLF, X for the
* data, 2 for the extra CRLF, so that's 5+X, while on the H2 side the smallest
* frame will be 9+X bytes based on the same buffer size. The HTTP/2 frame
* parser state is automatically updated. Returns the number of bytes emitted
* if > 0, or 0 if it couldn't proceed, in which case CS_FL_RCV_MORE must be
* checked to know if some data remain pending (an empty DATA frame can return
* 0 as a valid result). Stream errors are reported in h2s->errcode and
* connection errors in h2c->errcode. The caller must already have checked the
* frame header and ensured that the frame was complete or the buffer full. It
* changes the frame state to FRAME_A once done.
*/
static int h2_frt_transfer_data(struct h2s *h2s)
{
struct h2c *h2c = h2s->h2c;
int block1, block2;
unsigned int flen = 0;
unsigned int chklen = 0;
struct buffer *csbuf;
h2c->flags &= ~H2_CF_DEM_SFULL;
/* The padlen is the first byte before data, and the padding appears
* after data. padlen+data+padding are included in flen.
*/
if (h2c->dff & H2_F_DATA_PADDED) {
if (b_data(&h2c->dbuf) < 1)
return 0;
h2c->dpl = *(uint8_t *)b_head(&h2c->dbuf);
if (h2c->dpl >= h2c->dfl) {
/* RFC7540#6.1 : pad length = length of frame payload or greater */
h2c_error(h2c, H2_ERR_PROTOCOL_ERROR);
return 0;
}
/* skip the padlen byte */
b_del(&h2c->dbuf, 1);
h2c->dfl--;
h2c->rcvd_c++; h2c->rcvd_s++;
h2c->dff &= ~H2_F_DATA_PADDED;
}
csbuf = h2_get_buf(h2c, &h2s->cs->rxbuf);
if (!csbuf) {
h2c->flags |= H2_CF_DEM_SALLOC;
goto fail;
}
flen = h2c->dfl - h2c->dpl;
if (!flen)
goto end_transfer;
if (flen > b_data(&h2c->dbuf)) {
flen = b_data(&h2c->dbuf);
if (!flen)
goto fail;
}
if (unlikely(b_space_wraps(csbuf))) {
/* it doesn't fit and the buffer is fragmented,
* so let's defragment it and try again.
*/
b_slow_realign(csbuf, trash.area, 0);
}
/* chunked-encoding requires more room */
if (h2s->flags & H2_SF_DATA_CHNK) {
chklen = MIN(flen, b_room(csbuf));
chklen = (chklen < 16) ? 1 : (chklen < 256) ? 2 :
(chklen < 4096) ? 3 : (chklen < 65536) ? 4 :
(chklen < 1048576) ? 4 : 8;
chklen += 4; // CRLF, CRLF
}
/* does it fit in output buffer or should we wait ? */
if (flen + chklen > b_room(csbuf)) {
if (chklen >= b_room(csbuf)) {
h2c->flags |= H2_CF_DEM_SFULL;
goto fail;
}
flen = b_room(csbuf) - chklen;
}
if (h2s->flags & H2_SF_DATA_CHNK) {
/* emit the chunk size */
unsigned int chksz = flen;
char str[10];
char *beg;
beg = str + sizeof(str);
*--beg = '\n';
*--beg = '\r';
do {
*--beg = hextab[chksz & 0xF];
} while (chksz >>= 4);
b_putblk(csbuf, beg, str + sizeof(str) - beg);
}
/* Block1 is the length of the first block before the buffer wraps,
* block2 is the optional second block to reach the end of the frame.
*/
block1 = b_contig_data(&h2c->dbuf, 0);
if (block1 > flen)
block1 = flen;
block2 = flen - block1;
if (block1)
b_putblk(csbuf, b_head(&h2c->dbuf), block1);
if (block2)
b_putblk(csbuf, b_peek(&h2c->dbuf, block1), block2);
if (h2s->flags & H2_SF_DATA_CHNK) {
/* emit the CRLF */
b_putblk(csbuf, "\r\n", 2);
}
/* now mark the input data as consumed (will be deleted from the buffer
* by the caller when seeing FRAME_A after sending the window update).
*/
b_del(&h2c->dbuf, flen);
h2c->dfl -= flen;
h2c->rcvd_c += flen;
h2c->rcvd_s += flen; // warning, this can also affect the closed streams!
if (h2c->dfl > h2c->dpl) {
/* more data available, transfer stalled on stream full */
h2c->flags |= H2_CF_DEM_SFULL;
goto fail;
}
end_transfer:
/* here we're done with the frame, all the payload (except padding) was
* transferred.
*/
if (h2c->dff & H2_F_DATA_END_STREAM && h2s->flags & H2_SF_DATA_CHNK) {
/* emit the trailing 0 CRLF CRLF */
if (b_room(csbuf) < 5) {
h2c->flags |= H2_CF_DEM_SFULL;
goto fail;
}
chklen += 5;
b_putblk(csbuf, "0\r\n\r\n", 5);
}
h2c->rcvd_c += h2c->dpl;
h2c->rcvd_s += h2c->dpl;
h2c->dpl = 0;
h2c->st0 = H2_CS_FRAME_A; // send the corresponding window update
if (h2c->dff & H2_F_DATA_END_STREAM) {
h2s->flags |= H2_SF_ES_RCVD;
h2s->cs->flags |= CS_FL_REOS;
}
return flen + chklen;
fail:
return 0;
}
/* Try to send a HEADERS frame matching HTTP/1 response present at offset <ofs>
* and for <max> bytes in buffer <buf> for the H2 stream <h2s>. Returns the
* number of bytes sent. The caller must check the stream's status to detect
* any error which might have happened subsequently to a successful send.
*/
static size_t h2s_frt_make_resp_headers(struct h2s *h2s, const struct buffer *buf, size_t ofs, size_t max)
{
struct http_hdr list[MAX_HTTP_HDR];
struct h2c *h2c = h2s->h2c;
struct h1m *h1m = &h2s->res;
struct buffer outbuf;
int es_now = 0;
int ret = 0;
int hdr;
if (h2c_mux_busy(h2c, h2s)) {
h2s->flags |= H2_SF_BLK_MBUSY;
return 0;
}
if (!h2_get_buf(h2c, &h2c->mbuf)) {
h2c->flags |= H2_CF_MUX_MALLOC;
h2s->flags |= H2_SF_BLK_MROOM;
return 0;
}
/* First, try to parse the H1 response and index it into <list>.
* NOTE! Since it comes from haproxy, we *know* that a response header
* block does not wrap and we can safely read it this way without
* having to realign the buffer.
*/
ret = h1_headers_to_hdr_list(b_peek(buf, ofs), b_peek(buf, ofs) + max,
list, sizeof(list)/sizeof(list[0]), h1m);
if (ret <= 0) {
/* incomplete or invalid response, this is abnormal coming from
* haproxy and may only result in a bad errorfile or bad Lua code
* so that won't be fixed, raise an error now.
*
* FIXME: we should instead add the ability to only return a
* 502 bad gateway. But in theory this is not supposed to
* happen.
*/
h2s_error(h2s, H2_ERR_INTERNAL_ERROR);
ret = 0;
goto end;
}
chunk_reset(&outbuf);
while (1) {
outbuf.area = b_tail(&h2c->mbuf);
outbuf.size = b_contig_space(&h2c->mbuf);
outbuf.data = 0;
if (outbuf.size >= 9 || !b_space_wraps(&h2c->mbuf))
break;
realign_again:
b_slow_realign(&h2c->mbuf, trash.area, b_data(&h2c->mbuf));
}
if (outbuf.size < 9) {
h2c->flags |= H2_CF_MUX_MFULL;
h2s->flags |= H2_SF_BLK_MROOM;
ret = 0;
goto end;
}
/* len: 0x000000 (fill later), type: 1(HEADERS), flags: ENDH=4 */
memcpy(outbuf.area, "\x00\x00\x00\x01\x04", 5);
write_n32(outbuf.area + 5, h2s->id); // 4 bytes
outbuf.data = 9;
/* encode status, which necessarily is the first one */
if (outbuf.data < outbuf.size && h1m->status == 200)
outbuf.area[outbuf.data++] = 0x88; // indexed field : idx[08]=(":status", "200")
else if (outbuf.data < outbuf.size && h1m->status == 304)
outbuf.area[outbuf.data++] = 0x8b; // indexed field : idx[11]=(":status", "304")
else if (unlikely(list[0].v.len != 3)) {
/* this is an unparsable response */
h2s_error(h2s, H2_ERR_INTERNAL_ERROR);
ret = 0;
goto end;
}
else if (unlikely(outbuf.data + 2 + 3 <= outbuf.size)) {
/* basic encoding of the status code */
outbuf.area[outbuf.data++] = 0x48; // indexed name -- name=":status" (idx 8)
outbuf.area[outbuf.data++] = 0x03; // 3 bytes status
outbuf.area[outbuf.data++] = list[0].v.ptr[0];
outbuf.area[outbuf.data++] = list[0].v.ptr[1];
outbuf.area[outbuf.data++] = list[0].v.ptr[2];
}
else {
if (b_space_wraps(&h2c->mbuf))
goto realign_again;
h2c->flags |= H2_CF_MUX_MFULL;
h2s->flags |= H2_SF_BLK_MROOM;
ret = 0;
goto end;
}
/* encode all headers, stop at empty name */
for (hdr = 1; hdr < sizeof(list)/sizeof(list[0]); hdr++) {
/* these ones do not exist in H2 and must be dropped. */
if (isteq(list[hdr].n, ist("connection")) ||
isteq(list[hdr].n, ist("proxy-connection")) ||
isteq(list[hdr].n, ist("keep-alive")) ||
isteq(list[hdr].n, ist("upgrade")) ||
isteq(list[hdr].n, ist("transfer-encoding")))
continue;
if (isteq(list[hdr].n, ist("")))
break; // end
if (!hpack_encode_header(&outbuf, list[hdr].n, list[hdr].v)) {
/* output full */
if (b_space_wraps(&h2c->mbuf))
goto realign_again;
h2c->flags |= H2_CF_MUX_MFULL;
h2s->flags |= H2_SF_BLK_MROOM;
ret = 0;
goto end;
}
}
/* we may need to add END_STREAM */
if (((h1m->flags & H1_MF_CLEN) && !h1m->body_len) || h2s->cs->flags & CS_FL_SHW)
es_now = 1;
/* update the frame's size */
h2_set_frame_size(outbuf.area, outbuf.data - 9);
if (es_now)
outbuf.area[4] |= H2_F_HEADERS_END_STREAM;
/* consume incoming H1 response */
max -= ret;
/* commit the H2 response */
b_add(&h2c->mbuf, outbuf.data);
h2s->flags |= H2_SF_HEADERS_SENT;
/* for now we don't implemented CONTINUATION, so we wait for a
* body or directly end in TRL2.
*/
if (es_now) {
// trim any possibly pending data (eg: inconsistent content-length)
ret += max;
h1m->state = HTTP_MSG_DONE;
h2s->flags |= H2_SF_ES_SENT;
if (h2s->st == H2_SS_OPEN)
h2s->st = H2_SS_HLOC;
else
h2s_close(h2s);
}
else if (h1m->status >= 100 && h1m->status < 200) {
/* we'll let the caller check if it has more headers to send */
h1m->state = HTTP_MSG_RPBEFORE;
h1m->status = 0;
h1m->flags = 0;
goto end;
}
else
h1m->state = (h1m->flags & H1_MF_CHNK) ? HTTP_MSG_CHUNK_SIZE : HTTP_MSG_BODY;
end:
//fprintf(stderr, "[%d] sent simple H2 response (sid=%d) = %d bytes (%d in, ep=%u, es=%s)\n", h2c->st0, h2s->id, outbuf.len, ret, h1m->err_pos, h1_msg_state_str(h1m->err_state));
return ret;
}
/* Try to send a DATA frame matching HTTP/1 response present at offset <ofs>
* for up to <max> bytes in response buffer <buf>, for stream <h2s>. Returns
* the number of bytes sent. The caller must check the stream's status to
* detect any error which might have happened subsequently to a successful send.
*/
static size_t h2s_frt_make_resp_data(struct h2s *h2s, const struct buffer *buf, size_t ofs, size_t max)
{
struct h2c *h2c = h2s->h2c;
struct h1m *h1m = &h2s->res;
struct buffer outbuf;
int ret = 0;
size_t total = 0;
int es_now = 0;
int size = 0;
const char *blk1, *blk2;
size_t len1, len2;
if (h2c_mux_busy(h2c, h2s)) {
h2s->flags |= H2_SF_BLK_MBUSY;
goto end;
}
if (!h2_get_buf(h2c, &h2c->mbuf)) {
h2c->flags |= H2_CF_MUX_MALLOC;
h2s->flags |= H2_SF_BLK_MROOM;
goto end;
}
new_frame:
if (!max)
goto end;
chunk_reset(&outbuf);
while (1) {
outbuf.area = b_tail(&h2c->mbuf);
outbuf.size = b_contig_space(&h2c->mbuf);
outbuf.data = 0;
if (outbuf.size >= 9 || !b_space_wraps(&h2c->mbuf))
break;
realign_again:
b_slow_realign(&h2c->mbuf, trash.area, b_data(&h2c->mbuf));
}
if (outbuf.size < 9) {
h2c->flags |= H2_CF_MUX_MFULL;
h2s->flags |= H2_SF_BLK_MROOM;
goto end;
}
/* len: 0x000000 (fill later), type: 0(DATA), flags: none=0 */
memcpy(outbuf.area, "\x00\x00\x00\x00\x00", 5);
write_n32(outbuf.area + 5, h2s->id); // 4 bytes
outbuf.data = 9;
switch (h1m->flags & (H1_MF_CLEN|H1_MF_CHNK)) {
case 0: /* no content length, read till SHUTW */
size = max;
h1m->curr_len = size;
break;
case H1_MF_CLEN: /* content-length: read only h2m->body_len */
size = max;
if ((long long)size > h1m->curr_len)
size = h1m->curr_len;
break;
default: /* te:chunked : parse chunks */
if (h1m->state == HTTP_MSG_CHUNK_CRLF) {
ret = h1_skip_chunk_crlf(buf, ofs, ofs + max);
if (!ret)
goto end;
if (ret < 0) {
/* FIXME: bad contents. how to proceed here when we're in H2 ? */
h1m->err_pos = ret;
h2s_error(h2s, H2_ERR_INTERNAL_ERROR);
goto end;
}
max -= ret;
ofs += ret;
total += ret;
h1m->state = HTTP_MSG_CHUNK_SIZE;
}
if (h1m->state == HTTP_MSG_CHUNK_SIZE) {
unsigned int chunk;
ret = h1_parse_chunk_size(buf, ofs, ofs + max, &chunk);
if (!ret)
goto end;
if (ret < 0) {
/* FIXME: bad contents. how to proceed here when we're in H2 ? */
h1m->err_pos = ret;
h2s_error(h2s, H2_ERR_INTERNAL_ERROR);
goto end;
}
size = chunk;
h1m->curr_len = chunk;
h1m->body_len += chunk;
max -= ret;
ofs += ret;
total += ret;
h1m->state = size ? HTTP_MSG_DATA : HTTP_MSG_TRAILERS;
if (!size)
goto send_empty;
}
/* in MSG_DATA state, continue below */
size = h1m->curr_len;
break;
}
/* we have in <size> the exact number of bytes we need to copy from
* the H1 buffer. We need to check this against the connection's and
* the stream's send windows, and to ensure that this fits in the max
* frame size and in the buffer's available space minus 9 bytes (for
* the frame header). The connection's flow control is applied last so
* that we can use a separate list of streams which are immediately
* unblocked on window opening. Note: we don't implement padding.
*/
if (size > max)
size = max;
if (size > h2s->mws)
size = h2s->mws;
if (size <= 0) {
h2s->flags |= H2_SF_BLK_SFCTL;
goto end;
}
if (h2c->mfs && size > h2c->mfs)
size = h2c->mfs;
if (size + 9 > outbuf.size) {
/* we have an opportunity for enlarging the too small
* available space, let's try.
*/
if (b_space_wraps(&h2c->mbuf))
goto realign_again;
size = outbuf.size - 9;
}
if (size <= 0) {
h2c->flags |= H2_CF_MUX_MFULL;
h2s->flags |= H2_SF_BLK_MROOM;
goto end;
}
if (size > h2c->mws)
size = h2c->mws;
if (size <= 0) {
h2s->flags |= H2_SF_BLK_MFCTL;
goto end;
}
/* copy whatever we can */
blk1 = blk2 = NULL; // silence a maybe-uninitialized warning
ret = b_getblk_nc(buf, &blk1, &len1, &blk2, &len2, ofs, max);
if (ret == 1)
len2 = 0;
if (!ret || len1 + len2 < size) {
/* FIXME: must normally never happen */
h2s_error(h2s, H2_ERR_INTERNAL_ERROR);
goto end;
}
/* limit len1/len2 to size */
if (len1 + len2 > size) {
int sub = len1 + len2 - size;
if (len2 > sub)
len2 -= sub;
else {
sub -= len2;
len2 = 0;
len1 -= sub;
}
}
/* now let's copy this this into the output buffer */
memcpy(outbuf.area + 9, blk1, len1);
if (len2)
memcpy(outbuf.area + 9 + len1, blk2, len2);
send_empty:
/* we may need to add END_STREAM */
/* FIXME: we should also detect shutdown(w) below, but how ? Maybe we
* could rely on the MSG_MORE flag as a hint for this ?
*
* FIXME: what we do here is not correct because we send end_stream
* before knowing if we'll have to send a HEADERS frame for the
* trailers. More importantly we're not consuming the trailing CRLF
* after the end of trailers, so it will be left to the caller to
* eat it. The right way to do it would be to measure trailers here
* and to send ES only if there are no trailers.
*
*/
if (((h1m->flags & H1_MF_CLEN) && !(h1m->curr_len - size)) ||
!h1m->curr_len || h1m->state >= HTTP_MSG_DONE)
es_now = 1;
/* update the frame's size */
h2_set_frame_size(outbuf.area, size);
if (es_now)
outbuf.area[4] |= H2_F_DATA_END_STREAM;
/* commit the H2 response */
b_add(&h2c->mbuf, size + 9);
/* consume incoming H1 response */
if (size > 0) {
max -= size;
ofs += size;
total += size;
h1m->curr_len -= size;
h2s->mws -= size;
h2c->mws -= size;
if (size && !h1m->curr_len && (h1m->flags & H1_MF_CHNK)) {
h1m->state = HTTP_MSG_CHUNK_CRLF;
goto new_frame;
}
}
if (es_now) {
if (h2s->st == H2_SS_OPEN)
h2s->st = H2_SS_HLOC;
else
h2s_close(h2s);
if (!(h1m->flags & H1_MF_CHNK)) {
// trim any possibly pending data (eg: inconsistent content-length)
total += max;
ofs += max;
max = 0;
h1m->state = HTTP_MSG_DONE;
}
h2s->flags |= H2_SF_ES_SENT;
}
end:
trace("[%d] sent simple H2 DATA response (sid=%d) = %d bytes out (%u in, st=%s, ep=%u, es=%s, h2cws=%d h2sws=%d) data=%u", h2c->st0, h2s->id, size+9, (unsigned int)total, h1_msg_state_str(h1m->state), h1m->err_pos, h1_msg_state_str(h1m->err_state), h2c->mws, h2s->mws, (unsigned int)b_data(buf));
return total;
}
/* Called from the upper layer, to subscribe to events, such as being able to send */
static int h2_subscribe(struct conn_stream *cs, int event_type, void *param)
{
struct wait_list *sw;
struct h2s *h2s = cs->ctx;
switch (event_type) {
case SUB_CAN_SEND:
sw = param;
if (LIST_ISEMPTY(&h2s->list) && LIST_ISEMPTY(&sw->list))
LIST_ADDQ(&h2s->h2c->send_wait_list, &sw->list);
return 0;
default:
break;
}
return -1;
}
/* Called from the upper layer, to send data */
static size_t h2_snd_buf(struct conn_stream *cs, const struct buffer *buf, size_t count, int flags)
{
struct h2s *h2s = cs->ctx;
size_t total = 0;
size_t ret;
if (!(h2s->flags & H2_SF_OUTGOING_DATA) && count)
h2s->flags |= H2_SF_OUTGOING_DATA;
while (h2s->res.state < HTTP_MSG_DONE && count) {
if (h2s->res.state < HTTP_MSG_BODY) {
ret = h2s_frt_make_resp_headers(h2s, buf, total, count);
}
else if (h2s->res.state < HTTP_MSG_TRAILERS) {
ret = h2s_frt_make_resp_data(h2s, buf, total, count);
}
else if (h2s->res.state == HTTP_MSG_TRAILERS) {
/* consume the trailers if any (we don't forward them for now) */
ret = h1_measure_trailers(buf, total, count);
if (unlikely((int)ret <= 0)) {
if ((int)ret < 0)
h2s_error(h2s, H2_ERR_INTERNAL_ERROR);
break;
}
// trim any possibly pending data (eg: extra CR-LF, ...)
total += count;
count = 0;
h2s->res.state = HTTP_MSG_DONE;
break;
}
else {
cs->flags |= CS_FL_ERROR;
break;
}
total += ret;
count -= ret;
if (h2s->st >= H2_SS_ERROR)
break;
if (h2s->flags & H2_SF_BLK_ANY)
break;
}
if (h2s->st >= H2_SS_ERROR) {
/* trim any possibly pending data after we close (extra CR-LF,
* unprocessed trailers, abnormal extra data, ...)
*/
total += count;
count = 0;
}
/* RST are sent similarly to frame acks */
if (h2s->st == H2_SS_ERROR || h2s->flags & H2_SF_RST_RCVD) {
cs->flags |= CS_FL_ERROR;
if (h2s_send_rst_stream(h2s->h2c, h2s) > 0)
h2s_close(h2s);
}
if (h2s->flags & H2_SF_BLK_SFCTL) {
/* stream flow control, quit the list */
LIST_DEL(&h2s->list);
LIST_INIT(&h2s->list);
}
else if (LIST_ISEMPTY(&h2s->list)) {
if (h2s->flags & H2_SF_BLK_MFCTL)
LIST_ADDQ(&h2s->h2c->fctl_list, &h2s->list);
}
return total;
}
/* for debugging with CLI's "show fd" command */
static void h2_show_fd(struct buffer *msg, struct connection *conn)
{
struct h2c *h2c = conn->mux_ctx;
struct h2s *h2s;
struct eb32_node *node;
int fctl_cnt = 0;
int send_cnt = 0;
int tree_cnt = 0;
int orph_cnt = 0;
if (!h2c)
return;
list_for_each_entry(h2s, &h2c->fctl_list, list)
fctl_cnt++;
list_for_each_entry(h2s, &h2c->send_list, list)
send_cnt++;
node = eb32_first(&h2c->streams_by_id);
while (node) {
h2s = container_of(node, struct h2s, by_id);
tree_cnt++;
if (!h2s->cs)
orph_cnt++;
node = eb32_next(node);
}
chunk_appendf(msg, " st0=%d err=%d maxid=%d lastid=%d flg=0x%08x nbst=%u nbcs=%u"
" fctl_cnt=%d send_cnt=%d tree_cnt=%d orph_cnt=%d dbuf=%u/%u mbuf=%u/%u",
h2c->st0, h2c->errcode, h2c->max_id, h2c->last_sid, h2c->flags,
h2c->nb_streams, h2c->nb_cs, fctl_cnt, send_cnt, tree_cnt, orph_cnt,
(unsigned int)b_data(&h2c->dbuf), (unsigned int)b_size(&h2c->dbuf),
(unsigned int)b_data(&h2c->mbuf), (unsigned int)b_size(&h2c->mbuf));
}
/*******************************************************/
/* functions below are dedicated to the config parsers */
/*******************************************************/
/* config parser for global "tune.h2.header-table-size" */
static int h2_parse_header_table_size(char **args, int section_type, struct proxy *curpx,
struct proxy *defpx, const char *file, int line,
char **err)
{
if (too_many_args(1, args, err, NULL))
return -1;
h2_settings_header_table_size = atoi(args[1]);
if (h2_settings_header_table_size < 4096 || h2_settings_header_table_size > 65536) {
memprintf(err, "'%s' expects a numeric value between 4096 and 65536.", args[0]);
return -1;
}
return 0;
}
/* config parser for global "tune.h2.initial-window-size" */
static int h2_parse_initial_window_size(char **args, int section_type, struct proxy *curpx,
struct proxy *defpx, const char *file, int line,
char **err)
{
if (too_many_args(1, args, err, NULL))
return -1;
h2_settings_initial_window_size = atoi(args[1]);
if (h2_settings_initial_window_size < 0) {
memprintf(err, "'%s' expects a positive numeric value.", args[0]);
return -1;
}
return 0;
}
/* config parser for global "tune.h2.max-concurrent-streams" */
static int h2_parse_max_concurrent_streams(char **args, int section_type, struct proxy *curpx,
struct proxy *defpx, const char *file, int line,
char **err)
{
if (too_many_args(1, args, err, NULL))
return -1;
h2_settings_max_concurrent_streams = atoi(args[1]);
if (h2_settings_max_concurrent_streams < 0) {
memprintf(err, "'%s' expects a positive numeric value.", args[0]);
return -1;
}
return 0;
}
/****************************************/
/* MUX initialization and instanciation */
/***************************************/
/* The mux operations */
const struct mux_ops h2_ops = {
.init = h2_init,
.recv = h2_recv,
.wake = h2_wake,
.update_poll = h2_update_poll,
.snd_buf = h2_snd_buf,
.subscribe = h2_subscribe,
.attach = h2_attach,
.detach = h2_detach,
.shutr = h2_shutr,
.shutw = h2_shutw,
.show_fd = h2_show_fd,
.flags = MX_FL_CLEAN_ABRT,
.name = "H2",
};
/* ALPN selection : this mux registers ALPN tolen "h2" */
static struct alpn_mux_list alpn_mux_h2 =
{ .token = IST("h2"), .mode = ALPN_MODE_HTTP, .mux = &h2_ops };
/* config keyword parsers */
static struct cfg_kw_list cfg_kws = {ILH, {
{ CFG_GLOBAL, "tune.h2.header-table-size", h2_parse_header_table_size },
{ CFG_GLOBAL, "tune.h2.initial-window-size", h2_parse_initial_window_size },
{ CFG_GLOBAL, "tune.h2.max-concurrent-streams", h2_parse_max_concurrent_streams },
{ 0, NULL, NULL }
}};
static void __h2_deinit(void)
{
pool_destroy(pool_head_h2s);
pool_destroy(pool_head_h2c);
}
__attribute__((constructor))
static void __h2_init(void)
{
alpn_register_mux(&alpn_mux_h2);
cfg_register_keywords(&cfg_kws);
hap_register_post_deinit(__h2_deinit);
pool_head_h2c = create_pool("h2c", sizeof(struct h2c), MEM_F_SHARED);
pool_head_h2s = create_pool("h2s", sizeof(struct h2s), MEM_F_SHARED);
}