/* * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. * Copyright (c) 2007 The University of Aberdeen, Scotland, UK * * An implementation of the DCCP protocol * * This code has been developed by the University of Waikato WAND * research group. For further information please see http://www.wand.net.nz/ * or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz * * This code also uses code from Lulea University, rereleased as GPL by its * authors: * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon * * Changes to meet Linux coding standards, to make it meet latest ccid3 draft * and to make it work as a loadable module in the DCCP stack written by * Arnaldo Carvalho de Melo . * * Copyright (c) 2005 Arnaldo Carvalho de Melo * * 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. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #ifndef _DCCP_CCID3_H_ #define _DCCP_CCID3_H_ #include #include #include #include #include "lib/tfrc.h" #include "../ccid.h" /* Two seconds as per RFC 5348, 4.2 */ #define TFRC_INITIAL_TIMEOUT (2 * USEC_PER_SEC) /* Parameter t_mbi from [RFC 3448, 4.3]: backoff interval in seconds */ #define TFRC_T_MBI 64 /* * The t_delta parameter (RFC 5348, 8.3): delays of less than %USEC_PER_MSEC are * rounded down to 0, since sk_reset_timer() here uses millisecond granularity. * Hence we can use a constant t_delta = %USEC_PER_MSEC when HZ >= 500. A coarse * resolution of HZ < 500 means that the error is below one timer tick (t_gran) * when using the constant t_delta = t_gran / 2 = %USEC_PER_SEC / (2 * HZ). */ #if (HZ >= 500) # define TFRC_T_DELTA USEC_PER_MSEC #else # define TFRC_T_DELTA (USEC_PER_SEC / (2 * HZ)) #endif enum ccid3_options { TFRC_OPT_LOSS_EVENT_RATE = 192, TFRC_OPT_LOSS_INTERVALS = 193, TFRC_OPT_RECEIVE_RATE = 194, }; /* TFRC sender states */ enum ccid3_hc_tx_states { TFRC_SSTATE_NO_SENT = 1, TFRC_SSTATE_NO_FBACK, TFRC_SSTATE_FBACK, }; /** * struct ccid3_hc_tx_sock - CCID3 sender half-connection socket * @tx_x: Current sending rate in 64 * bytes per second * @tx_x_recv: Receive rate in 64 * bytes per second * @tx_x_calc: Calculated rate in bytes per second * @tx_rtt: Estimate of current round trip time in usecs * @tx_p: Current loss event rate (0-1) scaled by 1000000 * @tx_s: Packet size in bytes * @tx_t_rto: Nofeedback Timer setting in usecs * @tx_t_ipi: Interpacket (send) interval (RFC 3448, 4.6) in usecs * @tx_state: Sender state, one of %ccid3_hc_tx_states * @tx_last_win_count: Last window counter sent * @tx_t_last_win_count: Timestamp of earliest packet * with last_win_count value sent * @tx_no_feedback_timer: Handle to no feedback timer * @tx_t_ld: Time last doubled during slow start * @tx_t_nom: Nominal send time of next packet * @tx_hist: Packet history */ struct ccid3_hc_tx_sock { u64 tx_x; u64 tx_x_recv; u32 tx_x_calc; u32 tx_rtt; u32 tx_p; u32 tx_t_rto; u32 tx_t_ipi; u16 tx_s; enum ccid3_hc_tx_states tx_state:8; u8 tx_last_win_count; ktime_t tx_t_last_win_count; struct timer_list tx_no_feedback_timer; ktime_t tx_t_ld; ktime_t tx_t_nom; struct tfrc_tx_hist_entry *tx_hist; }; static inline struct ccid3_hc_tx_sock *ccid3_hc_tx_sk(const struct sock *sk) { struct ccid3_hc_tx_sock *hctx = ccid_priv(dccp_sk(sk)->dccps_hc_tx_ccid); BUG_ON(hctx == NULL); return hctx; } /* TFRC receiver states */ enum ccid3_hc_rx_states { TFRC_RSTATE_NO_DATA = 1, TFRC_RSTATE_DATA, }; /** * struct ccid3_hc_rx_sock - CCID3 receiver half-connection socket * @rx_last_counter: Tracks window counter (RFC 4342, 8.1) * @rx_state: Receiver state, one of %ccid3_hc_rx_states * @rx_bytes_recv: Total sum of DCCP payload bytes * @rx_x_recv: Receiver estimate of send rate (RFC 3448, sec. 4.3) * @rx_rtt: Receiver estimate of RTT * @rx_tstamp_last_feedback: Time at which last feedback was sent * @rx_hist: Packet history (loss detection + RTT sampling) * @rx_li_hist: Loss Interval database * @rx_s: Received packet size in bytes * @rx_pinv: Inverse of Loss Event Rate (RFC 4342, sec. 8.5) */ struct ccid3_hc_rx_sock { u8 rx_last_counter:4; enum ccid3_hc_rx_states rx_state:8; u32 rx_bytes_recv; u32 rx_x_recv; u32 rx_rtt; ktime_t rx_tstamp_last_feedback; struct tfrc_rx_hist rx_hist; struct tfrc_loss_hist rx_li_hist; u16 rx_s; #define rx_pinv rx_li_hist.i_mean }; static inline struct ccid3_hc_rx_sock *ccid3_hc_rx_sk(const struct sock *sk) { struct ccid3_hc_rx_sock *hcrx = ccid_priv(dccp_sk(sk)->dccps_hc_rx_ccid); BUG_ON(hcrx == NULL); return hcrx; } #endif /* _DCCP_CCID3_H_ */