2  * Copyright 2022-2024 The OpenSSL Project Authors. All Rights Reserved.
23 int ossl_quic_txfc_init(QUIC_TXFC *txfc, QUIC_TXFC *conn_txfc)  in OSSL_SAFE_MATH_UNSIGNED()
25     if (conn_txfc != NULL && conn_txfc->parent != NULL)  in OSSL_SAFE_MATH_UNSIGNED()
28     txfc->swm                   = 0;  in OSSL_SAFE_MATH_UNSIGNED()
29     txfc->cwm                   = 0;  in OSSL_SAFE_MATH_UNSIGNED()
30     txfc->parent                = conn_txfc;  in OSSL_SAFE_MATH_UNSIGNED()
31     txfc->has_become_blocked    = 0;  in OSSL_SAFE_MATH_UNSIGNED()
37     return txfc->parent;  in ossl_quic_txfc_get_parent()
40 int ossl_quic_txfc_bump_cwm(QUIC_TXFC *txfc, uint64_t cwm)  in ossl_quic_txfc_bump_cwm()
42     if (cwm <= txfc->cwm)  in ossl_quic_txfc_bump_cwm()
45     txfc->cwm = cwm;  in ossl_quic_txfc_bump_cwm()
51     assert((txfc->swm + consumed) <= txfc->cwm);  in ossl_quic_txfc_get_credit_local()
52     return txfc->cwm - (consumed + txfc->swm);  in ossl_quic_txfc_get_credit_local()
61     if (txfc->parent != NULL) {  in ossl_quic_txfc_get_credit()
62         assert(txfc->parent->parent == NULL);  in ossl_quic_txfc_get_credit()
63         conn_r = ossl_quic_txfc_get_credit_local(txfc->parent, consumed);  in ossl_quic_txfc_get_credit()
71 int ossl_quic_txfc_consume_credit_local(QUIC_TXFC *txfc, uint64_t num_bytes)  in ossl_quic_txfc_consume_credit_local()
73     int ok = 1;  in ossl_quic_txfc_consume_credit_local()
82         txfc->has_become_blocked = 1;  in ossl_quic_txfc_consume_credit_local()
84     txfc->swm += num_bytes;  in ossl_quic_txfc_consume_credit_local()
88 int ossl_quic_txfc_consume_credit(QUIC_TXFC *txfc, uint64_t num_bytes)  in ossl_quic_txfc_consume_credit()
90     int ok = ossl_quic_txfc_consume_credit_local(txfc, num_bytes);  in ossl_quic_txfc_consume_credit()
92     if (txfc->parent != NULL) {  in ossl_quic_txfc_consume_credit()
93         assert(txfc->parent->parent == NULL);  in ossl_quic_txfc_consume_credit()
94         if (!ossl_quic_txfc_consume_credit_local(txfc->parent, num_bytes))  in ossl_quic_txfc_consume_credit()
101 int ossl_quic_txfc_has_become_blocked(QUIC_TXFC *txfc, int clear)  in ossl_quic_txfc_has_become_blocked()
103     int r = txfc->has_become_blocked;  in ossl_quic_txfc_has_become_blocked()
106         txfc->has_become_blocked = 0;  in ossl_quic_txfc_has_become_blocked()
113     return txfc->cwm;  in ossl_quic_txfc_get_cwm()
118     return txfc->swm;  in ossl_quic_txfc_get_swm()
126 int ossl_quic_rxfc_init(QUIC_RXFC *rxfc, QUIC_RXFC *conn_rxfc,  in ossl_quic_rxfc_init()
132     if (conn_rxfc != NULL && conn_rxfc->parent != NULL)  in ossl_quic_rxfc_init()
135     rxfc->swm               = 0;  in ossl_quic_rxfc_init()
136     rxfc->cwm               = initial_window_size;  in ossl_quic_rxfc_init()
137     rxfc->rwm               = 0;  in ossl_quic_rxfc_init()
138     rxfc->esrwm             = 0;  in ossl_quic_rxfc_init()
139     rxfc->hwm               = 0;  in ossl_quic_rxfc_init()
140     rxfc->cur_window_size   = initial_window_size;  in ossl_quic_rxfc_init()
141     rxfc->max_window_size   = max_window_size;  in ossl_quic_rxfc_init()
142     rxfc->parent            = conn_rxfc;  in ossl_quic_rxfc_init()
143     rxfc->error_code        = 0;  in ossl_quic_rxfc_init()
144     rxfc->has_cwm_changed   = 0;  in ossl_quic_rxfc_init()
145     rxfc->epoch_start       = ossl_time_zero();  in ossl_quic_rxfc_init()
146     rxfc->now               = now;  in ossl_quic_rxfc_init()
147     rxfc->now_arg           = now_arg;  in ossl_quic_rxfc_init()
148     rxfc->is_fin            = 0;  in ossl_quic_rxfc_init()
149     rxfc->standalone        = 0;  in ossl_quic_rxfc_init()
153 int ossl_quic_rxfc_init_standalone(QUIC_RXFC *rxfc,  in ossl_quic_rxfc_init_standalone()
163     rxfc->standalone = 1;  in ossl_quic_rxfc_init_standalone()
169     return rxfc->parent;  in ossl_quic_rxfc_get_parent()
175     rxfc->max_window_size = max_window_size;  in ossl_quic_rxfc_set_max_window_size()
180     rxfc->epoch_start   = rxfc->now(rxfc->now_arg);  in rxfc_start_epoch()
181     rxfc->esrwm         = rxfc->rwm;  in rxfc_start_epoch()
184 static int on_rx_controlled_bytes(QUIC_RXFC *rxfc, uint64_t num_bytes)  in on_rx_controlled_bytes()
186     int ok = 1;  in on_rx_controlled_bytes()
187     uint64_t credit = rxfc->cwm - rxfc->swm;  in on_rx_controlled_bytes()
192         rxfc->error_code = OSSL_QUIC_ERR_FLOW_CONTROL_ERROR;  in on_rx_controlled_bytes()
195     rxfc->swm += num_bytes;  in on_rx_controlled_bytes()
199 int ossl_quic_rxfc_on_rx_stream_frame(QUIC_RXFC *rxfc, uint64_t end, int is_fin)  in ossl_quic_rxfc_on_rx_stream_frame()
203     if (!rxfc->standalone && rxfc->parent == NULL)  in ossl_quic_rxfc_on_rx_stream_frame()
206     if (rxfc->is_fin && ((is_fin && rxfc->hwm != end) || end > rxfc->hwm)) {  in ossl_quic_rxfc_on_rx_stream_frame()
208         rxfc->error_code = OSSL_QUIC_ERR_FINAL_SIZE_ERROR;  in ossl_quic_rxfc_on_rx_stream_frame()
213         rxfc->is_fin = 1;  in ossl_quic_rxfc_on_rx_stream_frame()
215     if (end > rxfc->hwm) {  in ossl_quic_rxfc_on_rx_stream_frame()
216         delta = end - rxfc->hwm;  in ossl_quic_rxfc_on_rx_stream_frame()
217         rxfc->hwm = end;  in ossl_quic_rxfc_on_rx_stream_frame()
220         if (rxfc->parent != NULL)  in ossl_quic_rxfc_on_rx_stream_frame()
221             on_rx_controlled_bytes(rxfc->parent, delta); /* result ignored */  in ossl_quic_rxfc_on_rx_stream_frame()
222     } else if (end < rxfc->hwm && is_fin) {  in ossl_quic_rxfc_on_rx_stream_frame()
223         rxfc->error_code = OSSL_QUIC_ERR_FINAL_SIZE_ERROR;  in ossl_quic_rxfc_on_rx_stream_frame()
230 /* threshold = 3/4 */
234 static int rxfc_cwm_bump_desired(QUIC_RXFC *rxfc)  in rxfc_cwm_bump_desired()
236     int err = 0;  in rxfc_cwm_bump_desired()
237     uint64_t window_rem = rxfc->cwm - rxfc->rwm;  in rxfc_cwm_bump_desired()
238     uint64_t threshold  in rxfc_cwm_bump_desired()  local
239         = safe_muldiv_uint64_t(rxfc->cur_window_size,  in rxfc_cwm_bump_desired()
245          * 1/2 as the threshold.  in rxfc_cwm_bump_desired()
247         threshold = rxfc->cur_window_size / 2;  in rxfc_cwm_bump_desired()
253     return !rxfc->is_fin && window_rem <= threshold;  in rxfc_cwm_bump_desired()
256 static int rxfc_should_bump_window_size(QUIC_RXFC *rxfc, OSSL_TIME rtt)  in rxfc_should_bump_window_size()
265      * b        = rwm - esrwm  in rxfc_should_bump_window_size()
274      * our 64-bit nanosecond representation, which will afford plenty of  in rxfc_should_bump_window_size()
277     uint64_t  b = rxfc->rwm - rxfc->esrwm;  in rxfc_should_bump_window_size()
283     now      = rxfc->now(rxfc->now_arg);  in rxfc_should_bump_window_size()
284     dt       = ossl_time_subtract(now, rxfc->epoch_start);  in rxfc_should_bump_window_size()
285     t_window = ossl_time_muldiv(dt, rxfc->cur_window_size, b);  in rxfc_should_bump_window_size()
296     new_window_size = rxfc->cur_window_size;  in rxfc_adjust_window_size()
303     if (new_window_size > rxfc->max_window_size) /* takes precedence over min size */  in rxfc_adjust_window_size()
304         new_window_size = rxfc->max_window_size;  in rxfc_adjust_window_size()
306     rxfc->cur_window_size = new_window_size;  in rxfc_adjust_window_size()
320     new_cwm = rxfc->rwm + rxfc->cur_window_size;  in rxfc_update_cwm()
321     if (new_cwm > rxfc->cwm) {  in rxfc_update_cwm()
322         rxfc->cwm = new_cwm;  in rxfc_update_cwm()
323         rxfc->has_cwm_changed = 1;  in rxfc_update_cwm()
327 static int rxfc_on_retire(QUIC_RXFC *rxfc, uint64_t num_bytes,  in rxfc_on_retire()
331     if (ossl_time_is_zero(rxfc->epoch_start))  in rxfc_on_retire()
335     rxfc->rwm += num_bytes;  in rxfc_on_retire()
340 int ossl_quic_rxfc_on_retire(QUIC_RXFC *rxfc,  in ossl_quic_rxfc_on_retire()
344     if (rxfc->parent == NULL && !rxfc->standalone)  in ossl_quic_rxfc_on_retire()
350     if (rxfc->rwm + num_bytes > rxfc->swm)  in ossl_quic_rxfc_on_retire()
356     if (!rxfc->standalone)  in ossl_quic_rxfc_on_retire()
357         rxfc_on_retire(rxfc->parent, num_bytes, rxfc->cur_window_size, rtt);  in ossl_quic_rxfc_on_retire()
364     return rxfc->cwm;  in ossl_quic_rxfc_get_cwm()
369     return rxfc->swm;  in ossl_quic_rxfc_get_swm()
374     return rxfc->rwm;  in ossl_quic_rxfc_get_rwm()
379     return ossl_quic_rxfc_get_cwm(rxfc) - ossl_quic_rxfc_get_swm(rxfc);  in ossl_quic_rxfc_get_credit()
382 int ossl_quic_rxfc_has_cwm_changed(QUIC_RXFC *rxfc, int clear)  in ossl_quic_rxfc_has_cwm_changed()
384     int r = rxfc->has_cwm_changed;  in ossl_quic_rxfc_has_cwm_changed()
387         rxfc->has_cwm_changed = 0;  in ossl_quic_rxfc_has_cwm_changed()
392 int ossl_quic_rxfc_get_error(QUIC_RXFC *rxfc, int clear)  in ossl_quic_rxfc_get_error()
394     int r = rxfc->error_code;  in ossl_quic_rxfc_get_error()
397         rxfc->error_code = 0;  in ossl_quic_rxfc_get_error()
402 int ossl_quic_rxfc_get_final_size(const QUIC_RXFC *rxfc, uint64_t *final_size)  in ossl_quic_rxfc_get_final_size()
404     if (!rxfc->is_fin)  in ossl_quic_rxfc_get_final_size()
408         *final_size = rxfc->hwm;  in ossl_quic_rxfc_get_final_size()