2 * Copyright 2022 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
10 #ifndef OSSL_INTERNAL_QUIC_STREAM_H
11 # define OSSL_INTERNAL_QUIC_STREAM_H
14 #include "internal/e_os.h"
15 #include "internal/time.h"
16 #include "internal/quic_types.h"
17 #include "internal/quic_wire.h"
18 #include "internal/quic_record_tx.h"
19 #include "internal/quic_record_rx.h"
20 #include "internal/quic_fc.h"
21 #include "internal/quic_statm.h"
23 # ifndef OPENSSL_NO_QUIC
29 * The QUIC Send Stream Manager (QUIC_SSTREAM) is responsible for:
31 * - accepting octet strings of stream data;
33 * - generating corresponding STREAM frames;
35 * - receiving notifications of lost frames, in order to generate new STREAM
36 * frames for the lost data;
38 * - receiving notifications of acknowledged frames, in order to internally
39 * reuse memory used to store acknowledged stream data;
41 * - informing the caller of how much more stream data it can accept into
42 * its internal buffers, so as to ensure that the amount of unacknowledged
43 * data which can be written to a stream is not infinite and to allow the
44 * caller to manifest backpressure conditions to the user.
46 * The QUIC_SSTREAM is instantiated once for every stream with a send component
47 * (i.e., for a unidirectional send stream or for the send component of a
48 * bidirectional stream).
50 * Note: The terms 'TX' and 'RX' are used when referring to frames, packets and
51 * datagrams. The terms 'send' and 'receive' are used when referring to the
52 * stream abstraction. Applications send; we transmit.
54 typedef struct quic_sstream_st QUIC_SSTREAM;
57 * Instantiates a new QUIC_SSTREAM. init_buf_size specifies the initial size of
58 * the stream data buffer in bytes, which must be positive.
60 QUIC_SSTREAM *ossl_quic_sstream_new(size_t init_buf_size);
63 * Frees a QUIC_SSTREAM and associated stream data storage.
65 * Any iovecs returned by ossl_quic_sstream_get_stream_frame cease to be valid after
66 * calling this function.
68 void ossl_quic_sstream_free(QUIC_SSTREAM *qss);
71 * (For TX packetizer use.) Retrieves information about application stream data
72 * which is ready for transmission.
74 * *hdr is filled with the logical offset, maximum possible length of stream
75 * data which can be transmitted, and a pointer to the stream data to be
76 * transmitted. is_fin is set to 1 if hdr->offset + hdr->len is the final size
77 * of the stream and 0 otherwise. hdr->stream_id is not set; the caller must set
80 * The caller is not obligated to send all of the data. If the caller does not
81 * send all of the data, the caller must reduce hdr->len before serializing the
82 * header structure and must ensure that hdr->is_fin is cleared.
84 * hdr->has_explicit_len is always set. It is the caller's responsibility to
85 * clear this if it wants to use the optimization of omitting the length field,
86 * as only the caller can know when this optimization can be performed.
88 * *num_iov must be set to the size of the iov array at call time. When this
89 * function returns successfully, it is updated to the number of iov entries
90 * which have been written.
92 * The stream data may be split across up to two IOVs due to internal ring
93 * buffer organisation. The sum of the lengths of the IOVs and the value written
94 * to hdr->len will always match. If the caller decides to send less than
95 * hdr->len of stream data, it must adjust the IOVs accordingly. This may be
96 * done by updating hdr->len and then calling the utility function
97 * ossl_quic_sstream_adjust_iov().
99 * After committing one or more bytes returned by ossl_quic_sstream_get_stream_frame to a
100 * packet, call ossl_quic_sstream_mark_transmitted with the inclusive range of logical
101 * byte numbers of the transmitted bytes (i.e., hdr->offset, hdr->offset +
102 * hdr->len - 1). If you do not call ossl_quic_sstream_mark_transmitted, the next call to
103 * ossl_quic_sstream_get_stream_frame will return the same data (or potentially the same
104 * and more, if more data has been appended by the application).
106 * It is the caller's responsibility to clamp the length of data which this
107 * function indicates is available according to other concerns, such as
108 * stream-level flow control, connection-level flow control, or the applicable
109 * maximum datagram payload length (MDPL) for a packet under construction.
111 * The skip argument can usually be given as zero. If it is non-zero, this
112 * function outputs a range which would be output if it were called again after
113 * calling ossl_quic_sstream_mark_transmitted() with the returned range, repeated 'skip'
114 * times, and so on. This may be useful for callers which wish to enumerate
115 * available stream frames and batch their calls to ossl_quic_sstream_mark_transmitted at
118 * On success, this function will never write *num_iov with a value other than
119 * 0, 1 or 2. A *num_iov value of 0 can only occurs when hdr->is_fin is set (for
120 * example, when a stream is closed after all existing data has been sent, and
121 * without sending any more data); otherwise the function returns 0 as there is
122 * nothing useful to report.
124 * Returns 1 on success and 0 if there is no stream data available for
125 * transmission, or on other error (such as if the caller provides fewer
128 int ossl_quic_sstream_get_stream_frame(QUIC_SSTREAM *qss,
130 OSSL_QUIC_FRAME_STREAM *hdr,
135 * Returns 1 if there is data pending transmission. Equivalent to calling
136 * ossl_quic_sstream_get_stream_frame and seeing if it succeeds.
138 int ossl_quic_sstream_has_pending(QUIC_SSTREAM *qss);
141 * Returns the current size of the stream; i.e., the number of bytes which have
142 * been appended to the stream so far.
144 uint64_t ossl_quic_sstream_get_cur_size(QUIC_SSTREAM *qss);
147 * (For TX packetizer use.) Marks a logical range of the send stream as having
150 * 0 denotes the first byte ever sent on the stream. The start and end values
151 * are both inclusive, therefore all calls to this function always mark at least
152 * one byte as being transmitted; if no bytes have been transmitted, do not call
155 * If the STREAM frame sent had the FIN bit set, you must also call
156 * ossl_quic_sstream_mark_transmitted_fin() after calling this function.
158 * If you sent a zero-length STREAM frame with the FIN bit set, you need only
159 * call ossl_quic_sstream_mark_transmitted_fin() and must not call this function.
161 * Returns 1 on success and 0 on error (e.g. if end < start).
163 int ossl_quic_sstream_mark_transmitted(QUIC_SSTREAM *qss,
168 * (For TX packetizer use.) Marks a STREAM frame with the FIN bit set as having
169 * been transmitted. final_size is the final size of the stream (i.e., the value
170 * offset + len of the transmitted STREAM frame).
172 * This function fails returning 0 if ossl_quic_sstream_fin() has not been called or if
173 * final_size is not correct. The final_size argument is not strictly needed by
174 * the QUIC_SSTREAM but is required as a sanity check.
176 int ossl_quic_sstream_mark_transmitted_fin(QUIC_SSTREAM *qss,
177 uint64_t final_size);
180 * (RX/ACKM use.) Marks a logical range of the send stream as having been lost.
181 * The send stream will return the lost data for retransmission on a future call
182 * to ossl_quic_sstream_get_stream_frame. The start and end values denote logical byte
183 * numbers and are inclusive.
185 * If the lost frame had the FIN bit set, you must also call
186 * ossl_quic_sstream_mark_lost_fin() after calling this function.
188 * Returns 1 on success and 0 on error (e.g. if end < start).
190 int ossl_quic_sstream_mark_lost(QUIC_SSTREAM *qss,
195 * (RX/ACKM use.) Informs the QUIC_SSTREAM that a STREAM frame with the FIN bit
198 * Returns 1 on success and 0 on error.
200 int ossl_quic_sstream_mark_lost_fin(QUIC_SSTREAM *qss);
203 * (RX/ACKM use.) Marks a logical range of the send stream as having been
204 * acknowledged, meaning that the storage for the data in that range of the
205 * stream can be now recycled and neither that logical range of the stream nor
206 * any subset of it can be retransmitted again. The start and end values are
209 * If the acknowledged frame had the FIN bit set, you must also call
210 * ossl_quic_sstream_mark_acked_fin() after calling this function.
212 * Returns 1 on success and 0 on error (e.g. if end < start).
214 int ossl_quic_sstream_mark_acked(QUIC_SSTREAM *qss,
219 * (RX/ACKM use.) Informs the QUIC_SSTREAM that a STREAM frame with the FIN bit
220 * set was acknowledged.
222 * Returns 1 on success and 0 on error.
224 int ossl_quic_sstream_mark_acked_fin(QUIC_SSTREAM *qss);
227 * (Front end use.) Appends user data to the stream. The data is copied into the
228 * stream. The amount of data consumed from buf is written to *consumed on
229 * success (short writes are possible). The amount of data which can be written
230 * can be determined in advance by calling the ossl_quic_sstream_get_buffer_avail()
231 * function; data is copied into an internal ring buffer of finite size.
233 * If the buffer is full, this should be materialised as a backpressure
234 * condition by the front end. This is not considered a failure condition;
235 * *consumed is written as 0 and the function returns 1.
237 * Returns 1 on success or 0 on failure.
239 int ossl_quic_sstream_append(QUIC_SSTREAM *qss,
240 const unsigned char *buf,
245 * Marks a stream as finished. ossl_quic_sstream_append() may not be called anymore
246 * after calling this.
248 void ossl_quic_sstream_fin(QUIC_SSTREAM *qss);
251 * If the stream has had ossl_quic_sstream_fin() called, returns 1 and writes
252 * the final size to *final_size. Otherwise, returns 0.
254 int ossl_quic_sstream_get_final_size(QUIC_SSTREAM *qss, uint64_t *final_size);
257 * Resizes the internal ring buffer. All stream data is preserved safely.
259 * This can be used to expand or contract the ring buffer, but not to contract
260 * the ring buffer below the amount of stream data currently stored in it.
261 * Returns 1 on success and 0 on failure.
263 * IMPORTANT: Any buffers referenced by iovecs output by
264 * ossl_quic_sstream_get_stream_frame() cease to be valid after calling this function.
266 int ossl_quic_sstream_set_buffer_size(QUIC_SSTREAM *qss, size_t num_bytes);
269 * Gets the internal ring buffer size in bytes.
271 size_t ossl_quic_sstream_get_buffer_size(QUIC_SSTREAM *qss);
274 * Gets the number of bytes used in the internal ring buffer.
276 size_t ossl_quic_sstream_get_buffer_used(QUIC_SSTREAM *qss);
279 * Gets the number of bytes free in the internal ring buffer.
281 size_t ossl_quic_sstream_get_buffer_avail(QUIC_SSTREAM *qss);
284 * Utility function to ensure the length of an array of iovecs matches the
285 * length given as len. Trailing iovecs have their length values reduced or set
288 void ossl_quic_sstream_adjust_iov(size_t len,
293 * QUIC Receive Stream Manager
294 * ===========================
296 * The QUIC Receive Stream Manager (QUIC_RSTREAM) is responsible for
297 * storing the received stream data frames until the application
298 * is able to read the data.
300 * The QUIC_RSTREAM is instantiated once for every stream that can receive data.
301 * (i.e., for a unidirectional receiving stream or for the receiving component
302 * of a bidirectional stream).
304 typedef struct quic_rstream_st QUIC_RSTREAM;
307 * Create a new instance of QUIC_RSTREAM with pointers to the flow
308 * controller and statistics module. They can be NULL for unit testing.
309 * If they are non-NULL, the `rxfc` is called when receive stream data
310 * is read by application. `statm` is queried for current rtt.
312 QUIC_RSTREAM *ossl_quic_rstream_new(QUIC_RXFC *rxfc,
316 * Frees a QUIC_RSTREAM and any associated storage.
318 void ossl_quic_rstream_free(QUIC_RSTREAM *qrs);
321 * Adds received stream frame data to `qrs`. The `pkt_wrap` refcount is
322 * incremented if the `data` is queued directly without copying.
323 * It can be NULL for unit-testing purposes, i.e. if `data` is static or
324 * never released before calling ossl_quic_rstream_free().
325 * The `offset` is the absolute offset of the data in the stream.
326 * `data_len` can be 0 - can be useful for indicating `fin` for empty stream.
327 * Or to indicate `fin` without any further data added to the stream.
330 int ossl_quic_rstream_queue_data(QUIC_RSTREAM *qrs, OSSL_QRX_PKT *pkt,
332 const unsigned char *data, uint64_t data_len,
336 * Copies the data from the stream storage to buffer `buf` of size `size`.
337 * `readbytes` is set to the number of bytes actually copied.
338 * `fin` is set to 1 if all the data from the stream were read so the
339 * stream is finished. It is set to 0 otherwise.
341 int ossl_quic_rstream_read(QUIC_RSTREAM *qrs, unsigned char *buf, size_t size,
342 size_t *readbytes, int *fin);
345 * Peeks at the data in the stream storage. It copies them to buffer `buf`
346 * of size `size` and sets `readbytes` to the number of bytes actually copied.
347 * `fin` is set to 1 if the copied data reach end of the stream.
348 * It is set to 0 otherwise.
350 int ossl_quic_rstream_peek(QUIC_RSTREAM *qrs, unsigned char *buf, size_t size,
351 size_t *readbytes, int *fin);
354 * Returns the size of the data available for reading. `fin` is set to 1 if
355 * after reading all the available data the stream will be finished,
356 * set to 0 otherwise.
358 int ossl_quic_rstream_available(QUIC_RSTREAM *qrs, size_t *avail, int *fin);