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Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001/*
2 * net/dccp/ccids/ccid3.c
3 *
Ian McDonaldb2f41ff2007-05-28 12:23:29 -03004 * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand.
5 * Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz>
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07006 *
7 * An implementation of the DCCP protocol
8 *
9 * This code has been developed by the University of Waikato WAND
10 * research group. For further information please see http://www.wand.net.nz/
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070011 *
12 * This code also uses code from Lulea University, rereleased as GPL by its
13 * authors:
14 * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
15 *
16 * Changes to meet Linux coding standards, to make it meet latest ccid3 draft
17 * and to make it work as a loadable module in the DCCP stack written by
18 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>.
19 *
20 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
21 *
22 * This program is free software; you can redistribute it and/or modify
23 * it under the terms of the GNU General Public License as published by
24 * the Free Software Foundation; either version 2 of the License, or
25 * (at your option) any later version.
26 *
27 * This program is distributed in the hope that it will be useful,
28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
30 * GNU General Public License for more details.
31 *
32 * You should have received a copy of the GNU General Public License
33 * along with this program; if not, write to the Free Software
34 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
35 */
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070036#include "../ccid.h"
37#include "../dccp.h"
Arnaldo Carvalho de Melo4524b252005-08-27 23:18:26 -030038#include "lib/packet_history.h"
Arnaldo Carvalho de Meloae6706f2005-08-27 23:03:09 -030039#include "lib/loss_interval.h"
Arnaldo Carvalho de Melo36729c12005-08-28 00:47:15 -030040#include "lib/tfrc.h"
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070041#include "ccid3.h"
42
Gerrit Renker56724aa2006-11-20 18:28:09 -020043#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
44static int ccid3_debug;
45#define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070046#else
47#define ccid3_pr_debug(format, a...)
48#endif
49
Arnaldo Carvalho de Meloa1d3a352005-08-13 22:42:25 -030050static struct dccp_tx_hist *ccid3_tx_hist;
51static struct dccp_rx_hist *ccid3_rx_hist;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070052
Gerrit Renker9bf17472007-03-20 13:11:24 -030053/*
54 * Transmitter Half-Connection Routines
55 */
Gerrit Renker56724aa2006-11-20 18:28:09 -020056#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070057static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state)
58{
59 static char *ccid3_state_names[] = {
60 [TFRC_SSTATE_NO_SENT] = "NO_SENT",
61 [TFRC_SSTATE_NO_FBACK] = "NO_FBACK",
62 [TFRC_SSTATE_FBACK] = "FBACK",
63 [TFRC_SSTATE_TERM] = "TERM",
64 };
65
66 return ccid3_state_names[state];
67}
68#endif
69
Arnaldo Carvalho de Meloc25a18b2006-03-20 21:58:56 -080070static void ccid3_hc_tx_set_state(struct sock *sk,
71 enum ccid3_hc_tx_states state)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070072{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -030073 struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070074 enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state;
75
76 ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -030077 dccp_role(sk), sk, ccid3_tx_state_name(oldstate),
78 ccid3_tx_state_name(state));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070079 WARN_ON(state == oldstate);
80 hctx->ccid3hctx_state = state;
81}
82
Gerrit Renker17893bc2006-11-27 20:31:33 -020083/*
Gerrit Renkera21f9f92007-03-20 15:12:10 -030084 * Compute the initial sending rate X_init according to RFC 3390:
85 * w_init = min(4 * MSS, max(2 * MSS, 4380 bytes))
86 * X_init = w_init / RTT
87 * For consistency with other parts of the code, X_init is scaled by 2^6.
88 */
89static inline u64 rfc3390_initial_rate(struct sock *sk)
90{
91 const struct dccp_sock *dp = dccp_sk(sk);
92 const __u32 w_init = min(4 * dp->dccps_mss_cache,
93 max(2 * dp->dccps_mss_cache, 4380U));
94
95 return scaled_div(w_init << 6, ccid3_hc_tx_sk(sk)->ccid3hctx_rtt);
96}
97
98/*
Gerrit Renker1266ade2007-03-20 14:56:11 -030099 * Recalculate t_ipi and delta (should be called whenever X changes)
Gerrit Renker17893bc2006-11-27 20:31:33 -0200100 */
Gerrit Renker1266ade2007-03-20 14:56:11 -0300101static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700102{
Gerrit Renker1a21e492006-12-10 00:02:12 -0200103 /* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */
Gerrit Renkerb2449fd2007-04-20 13:02:55 -0700104 hctx->ccid3hctx_t_ipi = scaled_div32(((u64)hctx->ccid3hctx_s) << 6,
105 hctx->ccid3hctx_x);
Gerrit Renker17893bc2006-11-27 20:31:33 -0200106
Gerrit Renker17893bc2006-11-27 20:31:33 -0200107 /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300108 hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2,
109 TFRC_OPSYS_HALF_TIME_GRAN);
Ian McDonald8699be72007-03-20 14:49:20 -0300110
Gerrit Renker1761f7d2007-03-20 15:04:30 -0300111 ccid3_pr_debug("t_ipi=%u, delta=%u, s=%u, X=%u\n",
Ian McDonald8699be72007-03-20 14:49:20 -0300112 hctx->ccid3hctx_t_ipi, hctx->ccid3hctx_delta,
Gerrit Renker1761f7d2007-03-20 15:04:30 -0300113 hctx->ccid3hctx_s, (unsigned)(hctx->ccid3hctx_x >> 6));
Ian McDonald8699be72007-03-20 14:49:20 -0300114
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700115}
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700116/*
117 * Update X by
118 * If (p > 0)
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200119 * X_calc = calcX(s, R, p);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700120 * X = max(min(X_calc, 2 * X_recv), s / t_mbi);
121 * Else
122 * If (now - tld >= R)
123 * X = max(min(2 * X, 2 * X_recv), s / R);
124 * tld = now;
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200125 *
Gerrit Renker1a21e492006-12-10 00:02:12 -0200126 * Note: X and X_recv are both stored in units of 64 * bytes/second, to support
127 * fine-grained resolution of sending rates. This requires scaling by 2^6
128 * throughout the code. Only X_calc is unscaled (in bytes/second).
129 *
Gerrit Renker1a21e492006-12-10 00:02:12 -0200130 */
Gerrit Renkera79ef762006-11-28 19:51:42 -0200131static void ccid3_hc_tx_update_x(struct sock *sk, struct timeval *now)
132
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700133{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300134 struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300135 __u64 min_rate = 2 * hctx->ccid3hctx_x_recv;
Gerrit Renker1a21e492006-12-10 00:02:12 -0200136 const __u64 old_x = hctx->ccid3hctx_x;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700137
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300138 /*
139 * Handle IDLE periods: do not reduce below RFC3390 initial sending rate
140 * when idling [RFC 4342, 5.1]. See also draft-ietf-dccp-rfc3448bis.
141 * For consistency with X and X_recv, min_rate is also scaled by 2^6.
142 */
143 if (unlikely(hctx->ccid3hctx_idle)) {
144 min_rate = rfc3390_initial_rate(sk);
145 min_rate = max(min_rate, 2 * hctx->ccid3hctx_x_recv);
146 }
147
Gerrit Renker44158302006-12-03 14:53:07 -0200148 if (hctx->ccid3hctx_p > 0) {
Gerrit Renker1a21e492006-12-10 00:02:12 -0200149
Gerrit Renker9e8efc82006-12-10 00:24:57 -0200150 hctx->ccid3hctx_x = min(((__u64)hctx->ccid3hctx_x_calc) << 6,
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300151 min_rate);
Gerrit Renker9e8efc82006-12-10 00:24:57 -0200152 hctx->ccid3hctx_x = max(hctx->ccid3hctx_x,
153 (((__u64)hctx->ccid3hctx_s) << 6) /
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200154 TFRC_T_MBI);
Arnaldo Carvalho de Melob6ee3d42005-08-27 18:18:18 -0300155
Gerrit Renker0f9e5b52006-12-10 00:03:51 -0200156 } else if (timeval_delta(now, &hctx->ccid3hctx_t_ld) -
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200157 (suseconds_t)hctx->ccid3hctx_rtt >= 0) {
Gerrit Renker1a21e492006-12-10 00:02:12 -0200158
Gerrit Renker9e8efc82006-12-10 00:24:57 -0200159 hctx->ccid3hctx_x =
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300160 max(min(2 * hctx->ccid3hctx_x, min_rate),
Gerrit Renker9e8efc82006-12-10 00:24:57 -0200161 scaled_div(((__u64)hctx->ccid3hctx_s) << 6,
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200162 hctx->ccid3hctx_rtt));
Gerrit Renkera79ef762006-11-28 19:51:42 -0200163 hctx->ccid3hctx_t_ld = *now;
Gerrit Renkerff586292006-12-10 00:00:14 -0200164 }
Gerrit Renkera79ef762006-11-28 19:51:42 -0200165
Ian McDonald8699be72007-03-20 14:49:20 -0300166 if (hctx->ccid3hctx_x != old_x) {
Gerrit Renker1761f7d2007-03-20 15:04:30 -0300167 ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, "
168 "X_recv=%u\n", (unsigned)(old_x >> 6),
169 (unsigned)(hctx->ccid3hctx_x >> 6),
170 hctx->ccid3hctx_x_calc,
171 (unsigned)(hctx->ccid3hctx_x_recv >> 6));
Ian McDonald8699be72007-03-20 14:49:20 -0300172
Gerrit Renker1266ade2007-03-20 14:56:11 -0300173 ccid3_update_send_interval(hctx);
Ian McDonald8699be72007-03-20 14:49:20 -0300174 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700175}
176
Gerrit Renker78ad7132006-11-28 19:22:33 -0200177/*
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200178 * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1)
179 * @len: DCCP packet payload size in bytes
Gerrit Renker78ad7132006-11-28 19:22:33 -0200180 */
181static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len)
182{
Gerrit Renker1266ade2007-03-20 14:56:11 -0300183 const u16 old_s = hctx->ccid3hctx_s;
184
185 hctx->ccid3hctx_s = old_s == 0 ? len : (9 * old_s + len) / 10;
186
187 if (hctx->ccid3hctx_s != old_s)
188 ccid3_update_send_interval(hctx);
Gerrit Renker78ad7132006-11-28 19:22:33 -0200189}
190
Gerrit Renker9f8681d2006-12-10 00:07:37 -0200191/*
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200192 * Update Window Counter using the algorithm from [RFC 4342, 8.1].
193 * The algorithm is not applicable if RTT < 4 microseconds.
Gerrit Renker9f8681d2006-12-10 00:07:37 -0200194 */
195static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hctx,
Gerrit Renker8132da42007-06-16 13:34:02 -0300196 ktime_t now)
Gerrit Renker9f8681d2006-12-10 00:07:37 -0200197{
Gerrit Renker9f8681d2006-12-10 00:07:37 -0200198 u32 quarter_rtts;
199
200 if (unlikely(hctx->ccid3hctx_rtt < 4)) /* avoid divide-by-zero */
201 return;
202
Gerrit Renker8132da42007-06-16 13:34:02 -0300203 quarter_rtts = ktime_us_delta(now, hctx->ccid3hctx_t_last_win_count);
204 quarter_rtts /= hctx->ccid3hctx_rtt / 4;
Gerrit Renker9f8681d2006-12-10 00:07:37 -0200205
206 if (quarter_rtts > 0) {
Gerrit Renker8132da42007-06-16 13:34:02 -0300207 hctx->ccid3hctx_t_last_win_count = now;
Gerrit Renker9f8681d2006-12-10 00:07:37 -0200208 hctx->ccid3hctx_last_win_count += min_t(u32, quarter_rtts, 5);
209 hctx->ccid3hctx_last_win_count &= 0xF; /* mod 16 */
Gerrit Renker9f8681d2006-12-10 00:07:37 -0200210 }
211}
212
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700213static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
214{
215 struct sock *sk = (struct sock *)data;
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300216 struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300217 struct timeval now;
Gerrit Renker2a1fda62006-11-28 18:34:34 -0200218 unsigned long t_nfb = USEC_PER_SEC / 5;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700219
220 bh_lock_sock(sk);
221 if (sock_owned_by_user(sk)) {
222 /* Try again later. */
223 /* XXX: set some sensible MIB */
Gerrit Renker48e03ee2006-11-27 20:29:27 -0200224 goto restart_timer;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700225 }
226
Gerrit Renkera9672412006-12-10 00:14:12 -0200227 ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk,
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700228 ccid3_tx_state_name(hctx->ccid3hctx_state));
Gerrit Renkera9672412006-12-10 00:14:12 -0200229
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300230 hctx->ccid3hctx_idle = 1;
231
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700232 switch (hctx->ccid3hctx_state) {
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700233 case TFRC_SSTATE_NO_FBACK:
Gerrit Renkera79ef762006-11-28 19:51:42 -0200234 /* RFC 3448, 4.4: Halve send rate directly */
Gerrit Renker9e8efc82006-12-10 00:24:57 -0200235 hctx->ccid3hctx_x = max(hctx->ccid3hctx_x / 2,
236 (((__u64)hctx->ccid3hctx_s) << 6) /
237 TFRC_T_MBI);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700238
Gerrit Renkera9672412006-12-10 00:14:12 -0200239 ccid3_pr_debug("%s(%p, state=%s), updated tx rate to %u "
240 "bytes/s\n", dccp_role(sk), sk,
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300241 ccid3_tx_state_name(hctx->ccid3hctx_state),
Gerrit Renker1a21e492006-12-10 00:02:12 -0200242 (unsigned)(hctx->ccid3hctx_x >> 6));
Gerrit Renker48e03ee2006-11-27 20:29:27 -0200243 /* The value of R is still undefined and so we can not recompute
244 * the timout value. Keep initial value as per [RFC 4342, 5]. */
Gerrit Renker2a1fda62006-11-28 18:34:34 -0200245 t_nfb = TFRC_INITIAL_TIMEOUT;
Gerrit Renker1266ade2007-03-20 14:56:11 -0300246 ccid3_update_send_interval(hctx);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700247 break;
248 case TFRC_SSTATE_FBACK:
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300249 /*
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300250 * Modify the cached value of X_recv [RFC 3448, 4.4]
251 *
252 * If (p == 0 || X_calc > 2 * X_recv)
253 * X_recv = max(X_recv / 2, s / (2 * t_mbi));
254 * Else
255 * X_recv = X_calc / 4;
256 *
257 * Note that X_recv is scaled by 2^6 while X_calc is not
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300258 */
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300259 BUG_ON(hctx->ccid3hctx_p && !hctx->ccid3hctx_x_calc);
Gerrit Renkera79ef762006-11-28 19:51:42 -0200260
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300261 if (hctx->ccid3hctx_p == 0 ||
262 (hctx->ccid3hctx_x_calc > (hctx->ccid3hctx_x_recv >> 5))) {
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700263
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300264 hctx->ccid3hctx_x_recv =
265 max(hctx->ccid3hctx_x_recv / 2,
266 (((__u64)hctx->ccid3hctx_s) << 6) /
267 (2 * TFRC_T_MBI));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700268
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300269 if (hctx->ccid3hctx_p == 0)
270 dccp_timestamp(sk, &now);
271 } else {
272 hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc;
273 hctx->ccid3hctx_x_recv <<= 4;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700274 }
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300275 /* Now recalculate X [RFC 3448, 4.3, step (4)] */
276 ccid3_hc_tx_update_x(sk, &now);
Arnaldo Carvalho de Melo6b5e6332005-08-27 20:11:28 -0300277 /*
278 * Schedule no feedback timer to expire in
Gerrit Renker8a508ac2006-12-03 14:50:23 -0200279 * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi)
280 * See comments in packet_recv() regarding the value of t_RTO.
Arnaldo Carvalho de Melo6b5e6332005-08-27 20:11:28 -0300281 */
Gerrit Renker8a508ac2006-12-03 14:50:23 -0200282 t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700283 break;
Gerrit Renker59348b12006-11-20 18:39:23 -0200284 case TFRC_SSTATE_NO_SENT:
Gerrit Renkera9672412006-12-10 00:14:12 -0200285 DCCP_BUG("%s(%p) - Illegal state NO_SENT", dccp_role(sk), sk);
Gerrit Renker59348b12006-11-20 18:39:23 -0200286 /* fall through */
287 case TFRC_SSTATE_TERM:
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700288 goto out;
289 }
290
Gerrit Renker48e03ee2006-11-27 20:29:27 -0200291restart_timer:
292 sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
YOSHIFUJI Hideakic9eaf172007-02-09 23:24:38 +0900293 jiffies + usecs_to_jiffies(t_nfb));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700294out:
295 bh_unlock_sock(sk);
296 sock_put(sk);
297}
298
Gerrit Renker7da7f452006-11-27 12:26:03 -0200299/*
300 * returns
301 * > 0: delay (in msecs) that should pass before actually sending
302 * = 0: can send immediately
303 * < 0: error condition; do not send packet
304 */
Gerrit Renker6b57c932006-11-28 19:55:06 -0200305static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700306{
307 struct dccp_sock *dp = dccp_sk(sk);
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300308 struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
Gerrit Renker8132da42007-06-16 13:34:02 -0300309 ktime_t now = ktime_get_real();
310 s64 delay;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700311
Gerrit Renker59348b12006-11-20 18:39:23 -0200312 BUG_ON(hctx == NULL);
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300313
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700314 /*
Gerrit Renkerda335ba2006-11-27 12:26:57 -0200315 * This function is called only for Data and DataAck packets. Sending
316 * zero-sized Data(Ack)s is theoretically possible, but for congestion
317 * control this case is pathological - ignore it.
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700318 */
Gerrit Renker6b57c932006-11-28 19:55:06 -0200319 if (unlikely(skb->len == 0))
Gerrit Renkerda335ba2006-11-27 12:26:57 -0200320 return -EBADMSG;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700321
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700322 switch (hctx->ccid3hctx_state) {
323 case TFRC_SSTATE_NO_SENT:
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300324 sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200325 (jiffies +
YOSHIFUJI Hideakic9eaf172007-02-09 23:24:38 +0900326 usecs_to_jiffies(TFRC_INITIAL_TIMEOUT)));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700327 hctx->ccid3hctx_last_win_count = 0;
328 hctx->ccid3hctx_t_last_win_count = now;
Gerrit Renker90feeb92006-11-27 12:13:38 -0200329
330 /* Set t_0 for initial packet */
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700331 hctx->ccid3hctx_t_nom = now;
Gerrit Renker30833ff2007-03-20 15:31:56 -0300332
333 hctx->ccid3hctx_s = skb->len;
334
335 /*
336 * Use initial RTT sample when available: recommended by erratum
337 * to RFC 4342. This implements the initialisation procedure of
338 * draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6.
339 */
340 if (dp->dccps_syn_rtt) {
341 ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt);
342 hctx->ccid3hctx_rtt = dp->dccps_syn_rtt;
343 hctx->ccid3hctx_x = rfc3390_initial_rate(sk);
Gerrit Renker8132da42007-06-16 13:34:02 -0300344 hctx->ccid3hctx_t_ld = ktime_to_timeval(now);
Gerrit Renker30833ff2007-03-20 15:31:56 -0300345 } else {
346 /* Sender does not have RTT sample: X = MSS/second */
347 hctx->ccid3hctx_x = dp->dccps_mss_cache;
348 hctx->ccid3hctx_x <<= 6;
349 }
350 ccid3_update_send_interval(hctx);
351
352 ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700353 break;
354 case TFRC_SSTATE_NO_FBACK:
355 case TFRC_SSTATE_FBACK:
Gerrit Renker8132da42007-06-16 13:34:02 -0300356 delay = ktime_us_delta(hctx->ccid3hctx_t_nom, now);
Ian McDonald8699be72007-03-20 14:49:20 -0300357 ccid3_pr_debug("delay=%ld\n", (long)delay);
Gerrit Renker91cf5a12006-11-27 12:25:10 -0200358 /*
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200359 * Scheduling of packet transmissions [RFC 3448, 4.6]
Gerrit Renker91cf5a12006-11-27 12:25:10 -0200360 *
361 * if (t_now > t_nom - delta)
362 * // send the packet now
363 * else
364 * // send the packet in (t_nom - t_now) milliseconds.
365 */
Gerrit Renker49d66a72007-06-16 13:48:50 -0300366 if (delay - (s64)hctx->ccid3hctx_delta >= 1000)
Gerrit Renker8132da42007-06-16 13:34:02 -0300367 return (u32)delay / 1000L;
Gerrit Renker9f8681d2006-12-10 00:07:37 -0200368
Gerrit Renker8132da42007-06-16 13:34:02 -0300369 ccid3_hc_tx_update_win_count(hctx, now);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700370 break;
Gerrit Renker59348b12006-11-20 18:39:23 -0200371 case TFRC_SSTATE_TERM:
Gerrit Renkera9672412006-12-10 00:14:12 -0200372 DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk);
Gerrit Renker7da7f452006-11-27 12:26:03 -0200373 return -EINVAL;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700374 }
375
Gerrit Renker7da7f452006-11-27 12:26:03 -0200376 /* prepare to send now (add options etc.) */
377 dp->dccps_hc_tx_insert_options = 1;
Gerrit Renkere312d102006-12-10 00:08:09 -0200378 DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count;
Gerrit Renker0c150ef2007-03-20 15:19:07 -0300379 hctx->ccid3hctx_idle = 0;
Gerrit Renkere312d102006-12-10 00:08:09 -0200380
381 /* set the nominal send time for the next following packet */
Gerrit Renker8132da42007-06-16 13:34:02 -0300382 hctx->ccid3hctx_t_nom = ktime_add_us(hctx->ccid3hctx_t_nom,
383 hctx->ccid3hctx_t_ipi);
Gerrit Renker7da7f452006-11-27 12:26:03 -0200384 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700385}
386
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200387static void ccid3_hc_tx_packet_sent(struct sock *sk, int more,
388 unsigned int len)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700389{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300390 struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700391 struct timeval now;
Gerrit Renker6b57c932006-11-28 19:55:06 -0200392 struct dccp_tx_hist_entry *packet;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700393
Gerrit Renker59348b12006-11-20 18:39:23 -0200394 BUG_ON(hctx == NULL);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700395
Gerrit Renker6b57c932006-11-28 19:55:06 -0200396 ccid3_hc_tx_update_s(hctx, len);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700397
Gerrit Renkerc5a1ae92006-12-10 00:09:21 -0200398 packet = dccp_tx_hist_entry_new(ccid3_tx_hist, GFP_ATOMIC);
Gerrit Renker6b57c932006-11-28 19:55:06 -0200399 if (unlikely(packet == NULL)) {
Gerrit Renkerc5a1ae92006-12-10 00:09:21 -0200400 DCCP_CRIT("packet history - out of memory!");
Gerrit Renker6b57c932006-11-28 19:55:06 -0200401 return;
402 }
Gerrit Renkerc5a1ae92006-12-10 00:09:21 -0200403 dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, packet);
404
405 dccp_timestamp(sk, &now);
Gerrit Renker6b57c932006-11-28 19:55:06 -0200406 packet->dccphtx_tstamp = now;
Gerrit Renkerc5a1ae92006-12-10 00:09:21 -0200407 packet->dccphtx_seqno = dccp_sk(sk)->dccps_gss;
408 packet->dccphtx_rtt = hctx->ccid3hctx_rtt;
409 packet->dccphtx_sent = 1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700410}
411
412static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
413{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300414 struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700415 struct ccid3_options_received *opt_recv;
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -0300416 struct dccp_tx_hist_entry *packet;
Arnaldo Carvalho de Melob0e56782005-09-09 02:38:35 -0300417 struct timeval now;
Gerrit Renker2a1fda62006-11-28 18:34:34 -0200418 unsigned long t_nfb;
Gerrit Renker7dfee1a2007-03-20 15:24:37 -0300419 u32 pinv, r_sample;
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300420
Gerrit Renker59348b12006-11-20 18:39:23 -0200421 BUG_ON(hctx == NULL);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700422
423 /* we are only interested in ACKs */
424 if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK ||
425 DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK))
426 return;
427
428 opt_recv = &hctx->ccid3hctx_options_received;
429
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700430 switch (hctx->ccid3hctx_state) {
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700431 case TFRC_SSTATE_NO_FBACK:
432 case TFRC_SSTATE_FBACK:
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200433 /* get packet from history to look up t_recvdata */
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -0300434 packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist,
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200435 DCCP_SKB_CB(skb)->dccpd_ack_seq);
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300436 if (unlikely(packet == NULL)) {
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200437 DCCP_WARN("%s(%p), seqno %llu(%s) doesn't exist "
Gerrit Renker59348b12006-11-20 18:39:23 -0200438 "in history!\n", dccp_role(sk), sk,
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300439 (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq,
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200440 dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700441 return;
442 }
443
Gerrit Renker1a21e492006-12-10 00:02:12 -0200444 /* Update receive rate in units of 64 * bytes/second */
Gerrit Renker9e8efc82006-12-10 00:24:57 -0200445 hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate;
446 hctx->ccid3hctx_x_recv <<= 6;
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200447
448 /* Update loss event rate */
449 pinv = opt_recv->ccid3or_loss_event_rate;
Gerrit Renker45393a62006-12-09 23:59:14 -0200450 if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200451 hctx->ccid3hctx_p = 0;
Gerrit Renker45393a62006-12-09 23:59:14 -0200452 else /* can not exceed 100% */
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200453 hctx->ccid3hctx_p = 1000000 / pinv;
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200454
Arnaldo Carvalho de Melob0e56782005-09-09 02:38:35 -0300455 dccp_timestamp(sk, &now);
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200456
457 /*
458 * Calculate new round trip sample as per [RFC 3448, 4.3] by
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200459 * R_sample = (now - t_recvdata) - t_elapsed
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200460 */
Gerrit Renker7dfee1a2007-03-20 15:24:37 -0300461 r_sample = dccp_sample_rtt(sk, &now, &packet->dccphtx_tstamp);
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200462
Gerrit Renker7dfee1a2007-03-20 15:24:37 -0300463 /*
464 * Update RTT estimate by
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700465 * If (No feedback recv)
466 * R = R_sample;
467 * Else
468 * R = q * R + (1 - q) * R_sample;
469 *
470 * q is a constant, RFC 3448 recomments 0.9
471 */
472 if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) {
Gerrit Renker1a21e492006-12-10 00:02:12 -0200473 /*
474 * Larger Initial Windows [RFC 4342, sec. 5]
Gerrit Renker1a21e492006-12-10 00:02:12 -0200475 */
Gerrit Renkera79ef762006-11-28 19:51:42 -0200476 hctx->ccid3hctx_rtt = r_sample;
Gerrit Renkera21f9f92007-03-20 15:12:10 -0300477 hctx->ccid3hctx_x = rfc3390_initial_rate(sk);
Gerrit Renkera79ef762006-11-28 19:51:42 -0200478 hctx->ccid3hctx_t_ld = now;
479
Gerrit Renker1266ade2007-03-20 14:56:11 -0300480 ccid3_update_send_interval(hctx);
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200481
Gerrit Renkera21f9f92007-03-20 15:12:10 -0300482 ccid3_pr_debug("%s(%p), s=%u, MSS=%u, "
Gerrit Renker7dfee1a2007-03-20 15:24:37 -0300483 "R_sample=%uus, X=%u\n", dccp_role(sk),
Andrew Morton0f084612007-02-05 18:18:21 -0800484 sk, hctx->ccid3hctx_s,
David S. Miller1b07a952007-05-23 17:43:11 -0700485 dccp_sk(sk)->dccps_mss_cache, r_sample,
Gerrit Renker1a21e492006-12-10 00:02:12 -0200486 (unsigned)(hctx->ccid3hctx_x >> 6));
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200487
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700488 ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK);
Gerrit Renkera79ef762006-11-28 19:51:42 -0200489 } else {
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200490 hctx->ccid3hctx_rtt = (9 * hctx->ccid3hctx_rtt +
Gerrit Renker7dfee1a2007-03-20 15:24:37 -0300491 r_sample) / 10;
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200492
Gerrit Renkerff586292006-12-10 00:00:14 -0200493 /* Update sending rate (step 4 of [RFC 3448, 4.3]) */
494 if (hctx->ccid3hctx_p > 0)
495 hctx->ccid3hctx_x_calc =
496 tfrc_calc_x(hctx->ccid3hctx_s,
497 hctx->ccid3hctx_rtt,
498 hctx->ccid3hctx_p);
Gerrit Renkera79ef762006-11-28 19:51:42 -0200499 ccid3_hc_tx_update_x(sk, &now);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700500
Gerrit Renker7dfee1a2007-03-20 15:24:37 -0300501 ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, "
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200502 "p=%u, X_calc=%u, X_recv=%u, X=%u\n",
503 dccp_role(sk),
Gerrit Renker7dfee1a2007-03-20 15:24:37 -0300504 sk, hctx->ccid3hctx_rtt, r_sample,
Gerrit Renker5c3fbb62006-12-03 14:50:56 -0200505 hctx->ccid3hctx_s, hctx->ccid3hctx_p,
506 hctx->ccid3hctx_x_calc,
Gerrit Renker9e8efc82006-12-10 00:24:57 -0200507 (unsigned)(hctx->ccid3hctx_x_recv >> 6),
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200508 (unsigned)(hctx->ccid3hctx_x >> 6));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700509 }
510
511 /* unschedule no feedback timer */
512 sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
513
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700514 /* remove all packets older than the one acked from history */
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -0300515 dccp_tx_hist_purge_older(ccid3_tx_hist,
516 &hctx->ccid3hctx_hist, packet);
Arnaldo Carvalho de Meloc530cfb2005-08-29 02:15:54 -0300517 /*
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200518 * As we have calculated new ipi, delta, t_nom it is possible
519 * that we now can send a packet, so wake up dccp_wait_for_ccid
Arnaldo Carvalho de Meloc530cfb2005-08-29 02:15:54 -0300520 */
521 sk->sk_write_space(sk);
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -0300522
Gerrit Renker8a508ac2006-12-03 14:50:23 -0200523 /*
524 * Update timeout interval for the nofeedback timer.
525 * We use a configuration option to increase the lower bound.
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200526 * This can help avoid triggering the nofeedback timer too
527 * often ('spinning') on LANs with small RTTs.
Gerrit Renker8a508ac2006-12-03 14:50:23 -0200528 */
Gerrit Renker5d0dbc42006-11-27 20:32:37 -0200529 hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt,
Gerrit Renker8a508ac2006-12-03 14:50:23 -0200530 CONFIG_IP_DCCP_CCID3_RTO *
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200531 (USEC_PER_SEC/1000));
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300532 /*
533 * Schedule no feedback timer to expire in
Gerrit Renker8a508ac2006-12-03 14:50:23 -0200534 * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi)
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300535 */
Gerrit Renker8a508ac2006-12-03 14:50:23 -0200536 t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700537
Gerrit Renkera9672412006-12-10 00:14:12 -0200538 ccid3_pr_debug("%s(%p), Scheduled no feedback timer to "
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200539 "expire in %lu jiffies (%luus)\n",
540 dccp_role(sk),
Gerrit Renkera9672412006-12-10 00:14:12 -0200541 sk, usecs_to_jiffies(t_nfb), t_nfb);
542
543 sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
Gerrit Renker2a1fda62006-11-28 18:34:34 -0200544 jiffies + usecs_to_jiffies(t_nfb));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700545
546 /* set idle flag */
Gerrit Renkerbf58a382006-12-10 00:04:43 -0200547 hctx->ccid3hctx_idle = 1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700548 break;
Gerrit Renker151a9932007-03-07 12:53:48 -0800549 case TFRC_SSTATE_NO_SENT: /* fall through */
Gerrit Renker5e19e3f2006-11-27 12:28:48 -0200550 case TFRC_SSTATE_TERM: /* ignore feedback when closing */
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700551 break;
552 }
553}
554
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700555static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option,
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300556 unsigned char len, u16 idx,
557 unsigned char *value)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700558{
559 int rc = 0;
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300560 const struct dccp_sock *dp = dccp_sk(sk);
561 struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700562 struct ccid3_options_received *opt_recv;
563
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300564 BUG_ON(hctx == NULL);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700565
566 opt_recv = &hctx->ccid3hctx_options_received;
567
568 if (opt_recv->ccid3or_seqno != dp->dccps_gsr) {
569 opt_recv->ccid3or_seqno = dp->dccps_gsr;
570 opt_recv->ccid3or_loss_event_rate = ~0;
571 opt_recv->ccid3or_loss_intervals_idx = 0;
572 opt_recv->ccid3or_loss_intervals_len = 0;
573 opt_recv->ccid3or_receive_rate = 0;
574 }
575
576 switch (option) {
577 case TFRC_OPT_LOSS_EVENT_RATE:
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300578 if (unlikely(len != 4)) {
Gerrit Renkera9672412006-12-10 00:14:12 -0200579 DCCP_WARN("%s(%p), invalid len %d "
Gerrit Renker59348b12006-11-20 18:39:23 -0200580 "for TFRC_OPT_LOSS_EVENT_RATE\n",
581 dccp_role(sk), sk, len);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700582 rc = -EINVAL;
583 } else {
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200584 opt_recv->ccid3or_loss_event_rate =
585 ntohl(*(__be32 *)value);
Gerrit Renkera9672412006-12-10 00:14:12 -0200586 ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n",
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700587 dccp_role(sk), sk,
588 opt_recv->ccid3or_loss_event_rate);
589 }
590 break;
591 case TFRC_OPT_LOSS_INTERVALS:
592 opt_recv->ccid3or_loss_intervals_idx = idx;
593 opt_recv->ccid3or_loss_intervals_len = len;
Gerrit Renkera9672412006-12-10 00:14:12 -0200594 ccid3_pr_debug("%s(%p), LOSS_INTERVALS=(%u, %u)\n",
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700595 dccp_role(sk), sk,
596 opt_recv->ccid3or_loss_intervals_idx,
597 opt_recv->ccid3or_loss_intervals_len);
598 break;
599 case TFRC_OPT_RECEIVE_RATE:
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300600 if (unlikely(len != 4)) {
Gerrit Renkera9672412006-12-10 00:14:12 -0200601 DCCP_WARN("%s(%p), invalid len %d "
Gerrit Renker59348b12006-11-20 18:39:23 -0200602 "for TFRC_OPT_RECEIVE_RATE\n",
603 dccp_role(sk), sk, len);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700604 rc = -EINVAL;
605 } else {
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200606 opt_recv->ccid3or_receive_rate =
607 ntohl(*(__be32 *)value);
Gerrit Renkera9672412006-12-10 00:14:12 -0200608 ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n",
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700609 dccp_role(sk), sk,
610 opt_recv->ccid3or_receive_rate);
611 }
612 break;
613 }
614
615 return rc;
616}
617
Arnaldo Carvalho de Melo91f0ebf2006-03-20 19:21:44 -0800618static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700619{
Arnaldo Carvalho de Melo91f0ebf2006-03-20 19:21:44 -0800620 struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700621
Gerrit Renker78ad7132006-11-28 19:22:33 -0200622 hctx->ccid3hctx_s = 0;
Gerrit Renkerfe0499a2006-12-10 00:06:01 -0200623 hctx->ccid3hctx_rtt = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700624 hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT;
625 INIT_LIST_HEAD(&hctx->ccid3hctx_hist);
Arnaldo Carvalho de Meloaa5d7df2006-03-20 17:35:13 -0800626
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200627 hctx->ccid3hctx_no_feedback_timer.function =
628 ccid3_hc_tx_no_feedback_timer;
Arnaldo Carvalho de Meloaa5d7df2006-03-20 17:35:13 -0800629 hctx->ccid3hctx_no_feedback_timer.data = (unsigned long)sk;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700630 init_timer(&hctx->ccid3hctx_no_feedback_timer);
631
632 return 0;
633}
634
635static void ccid3_hc_tx_exit(struct sock *sk)
636{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300637 struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700638
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700639 BUG_ON(hctx == NULL);
640
641 ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM);
642 sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
643
644 /* Empty packet history */
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -0300645 dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700646}
647
Gerrit Renker9bf17472007-03-20 13:11:24 -0300648static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info)
649{
650 const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700651
Gerrit Renker9bf17472007-03-20 13:11:24 -0300652 /* Listen socks doesn't have a private CCID block */
653 if (sk->sk_state == DCCP_LISTEN)
654 return;
655
656 BUG_ON(hctx == NULL);
657
658 info->tcpi_rto = hctx->ccid3hctx_t_rto;
659 info->tcpi_rtt = hctx->ccid3hctx_rtt;
660}
661
662static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len,
663 u32 __user *optval, int __user *optlen)
664{
665 const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
666 const void *val;
667
668 /* Listen socks doesn't have a private CCID block */
669 if (sk->sk_state == DCCP_LISTEN)
670 return -EINVAL;
671
672 switch (optname) {
673 case DCCP_SOCKOPT_CCID_TX_INFO:
674 if (len < sizeof(hctx->ccid3hctx_tfrc))
675 return -EINVAL;
676 len = sizeof(hctx->ccid3hctx_tfrc);
677 val = &hctx->ccid3hctx_tfrc;
678 break;
679 default:
680 return -ENOPROTOOPT;
681 }
682
683 if (put_user(len, optlen) || copy_to_user(optval, val, len))
684 return -EFAULT;
685
686 return 0;
687}
688
689/*
690 * Receiver Half-Connection Routines
691 */
Gerrit Renker56724aa2006-11-20 18:28:09 -0200692#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700693static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state)
694{
695 static char *ccid3_rx_state_names[] = {
696 [TFRC_RSTATE_NO_DATA] = "NO_DATA",
697 [TFRC_RSTATE_DATA] = "DATA",
698 [TFRC_RSTATE_TERM] = "TERM",
699 };
700
701 return ccid3_rx_state_names[state];
702}
703#endif
704
Arnaldo Carvalho de Meloc25a18b2006-03-20 21:58:56 -0800705static void ccid3_hc_rx_set_state(struct sock *sk,
706 enum ccid3_hc_rx_states state)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700707{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300708 struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700709 enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state;
710
711 ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300712 dccp_role(sk), sk, ccid3_rx_state_name(oldstate),
713 ccid3_rx_state_name(state));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700714 WARN_ON(state == oldstate);
715 hcrx->ccid3hcrx_state = state;
716}
717
Gerrit Renker78ad7132006-11-28 19:22:33 -0200718static inline void ccid3_hc_rx_update_s(struct ccid3_hc_rx_sock *hcrx, int len)
719{
720 if (unlikely(len == 0)) /* don't update on empty packets (e.g. ACKs) */
721 ccid3_pr_debug("Packet payload length is 0 - not updating\n");
722 else
723 hcrx->ccid3hcrx_s = hcrx->ccid3hcrx_s == 0 ? len :
724 (9 * hcrx->ccid3hcrx_s + len) / 10;
725}
726
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700727static void ccid3_hc_rx_send_feedback(struct sock *sk)
728{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300729 struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700730 struct dccp_sock *dp = dccp_sk(sk);
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -0300731 struct dccp_rx_hist_entry *packet;
Arnaldo Carvalho de Melob6ee3d42005-08-27 18:18:18 -0300732 struct timeval now;
Gerrit Renker0f9e5b52006-12-10 00:03:51 -0200733 suseconds_t delta;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700734
Gerrit Renkera9672412006-12-10 00:14:12 -0200735 ccid3_pr_debug("%s(%p) - entry \n", dccp_role(sk), sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700736
Arnaldo Carvalho de Melob0e56782005-09-09 02:38:35 -0300737 dccp_timestamp(sk, &now);
Arnaldo Carvalho de Melob6ee3d42005-08-27 18:18:18 -0300738
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700739 switch (hcrx->ccid3hcrx_state) {
740 case TFRC_RSTATE_NO_DATA:
741 hcrx->ccid3hcrx_x_recv = 0;
742 break;
Gerrit Renker0f9e5b52006-12-10 00:03:51 -0200743 case TFRC_RSTATE_DATA:
744 delta = timeval_delta(&now,
745 &hcrx->ccid3hcrx_tstamp_last_feedback);
746 DCCP_BUG_ON(delta < 0);
Gerrit Renkerb9039a22006-12-10 00:02:51 -0200747 hcrx->ccid3hcrx_x_recv =
748 scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700749 break;
Gerrit Renker59348b12006-11-20 18:39:23 -0200750 case TFRC_RSTATE_TERM:
Gerrit Renkera9672412006-12-10 00:14:12 -0200751 DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700752 return;
753 }
754
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -0300755 packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist);
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300756 if (unlikely(packet == NULL)) {
Gerrit Renkera9672412006-12-10 00:14:12 -0200757 DCCP_WARN("%s(%p), no data packet in history!\n",
Gerrit Renker59348b12006-11-20 18:39:23 -0200758 dccp_role(sk), sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700759 return;
760 }
761
Arnaldo Carvalho de Melob6ee3d42005-08-27 18:18:18 -0300762 hcrx->ccid3hcrx_tstamp_last_feedback = now;
Ian McDonald66a377c2006-08-26 23:40:50 -0700763 hcrx->ccid3hcrx_ccval_last_counter = packet->dccphrx_ccval;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700764 hcrx->ccid3hcrx_bytes_recv = 0;
765
Gerrit Renker0f9e5b52006-12-10 00:03:51 -0200766 /* Elapsed time information [RFC 4340, 13.2] in units of 10 * usecs */
767 delta = timeval_delta(&now, &packet->dccphrx_tstamp);
768 DCCP_BUG_ON(delta < 0);
769 hcrx->ccid3hcrx_elapsed_time = delta / 10;
Gerrit Renker45393a62006-12-09 23:59:14 -0200770
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700771 if (hcrx->ccid3hcrx_p == 0)
Gerrit Renker45393a62006-12-09 23:59:14 -0200772 hcrx->ccid3hcrx_pinv = ~0U; /* see RFC 4342, 8.5 */
773 else if (hcrx->ccid3hcrx_p > 1000000) {
774 DCCP_WARN("p (%u) > 100%%\n", hcrx->ccid3hcrx_p);
775 hcrx->ccid3hcrx_pinv = 1; /* use 100% in this case */
776 } else
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700777 hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p;
Gerrit Renker45393a62006-12-09 23:59:14 -0200778
Arnaldo Carvalho de Melo507d37c2005-09-09 02:30:07 -0300779 dp->dccps_hc_rx_insert_options = 1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700780 dccp_send_ack(sk);
781}
782
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800783static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700784{
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300785 const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800786 __be32 x_recv, pinv;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700787
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300788 BUG_ON(hcrx == NULL);
789
790 if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN))
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800791 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700792
Ian McDonald66a377c2006-08-26 23:40:50 -0700793 DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_ccval_last_counter;
Arnaldo Carvalho de Melo4fded332005-08-23 21:51:59 -0700794
795 if (dccp_packet_without_ack(skb))
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800796 return 0;
797
Arnaldo Carvalho de Melo4fded332005-08-23 21:51:59 -0700798 x_recv = htonl(hcrx->ccid3hcrx_x_recv);
799 pinv = htonl(hcrx->ccid3hcrx_pinv);
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800800
801 if ((hcrx->ccid3hcrx_elapsed_time != 0 &&
802 dccp_insert_option_elapsed_time(sk, skb,
803 hcrx->ccid3hcrx_elapsed_time)) ||
804 dccp_insert_option_timestamp(sk, skb) ||
805 dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE,
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200806 &pinv, sizeof(pinv)) ||
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800807 dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE,
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200808 &x_recv, sizeof(x_recv)))
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800809 return -1;
810
811 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700812}
813
Ian McDonald66a377c2006-08-26 23:40:50 -0700814static int ccid3_hc_rx_detect_loss(struct sock *sk,
YOSHIFUJI Hideakic9eaf172007-02-09 23:24:38 +0900815 struct dccp_rx_hist_entry *packet)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700816{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300817 struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200818 struct dccp_rx_hist_entry *rx_hist =
819 dccp_rx_hist_head(&hcrx->ccid3hcrx_hist);
Ian McDonald66a377c2006-08-26 23:40:50 -0700820 u64 seqno = packet->dccphrx_seqno;
821 u64 tmp_seqno;
822 int loss = 0;
823 u8 ccval;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700824
Ian McDonald66a377c2006-08-26 23:40:50 -0700825
826 tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss;
827
828 if (!rx_hist ||
829 follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) {
830 hcrx->ccid3hcrx_seqno_nonloss = seqno;
831 hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval;
832 goto detect_out;
833 }
834
835
836 while (dccp_delta_seqno(hcrx->ccid3hcrx_seqno_nonloss, seqno)
837 > TFRC_RECV_NUM_LATE_LOSS) {
838 loss = 1;
Arnaldo Carvalho de Melocc4d6a32007-05-28 18:53:08 -0300839 dccp_li_update_li(sk,
Arnaldo Carvalho de Melocc0a9102007-06-14 17:41:28 -0300840 &hcrx->ccid3hcrx_li_hist,
841 &hcrx->ccid3hcrx_hist,
842 &hcrx->ccid3hcrx_tstamp_last_feedback,
843 hcrx->ccid3hcrx_s,
844 hcrx->ccid3hcrx_bytes_recv,
845 hcrx->ccid3hcrx_x_recv,
846 hcrx->ccid3hcrx_seqno_nonloss,
847 hcrx->ccid3hcrx_ccval_nonloss);
Ian McDonald66a377c2006-08-26 23:40:50 -0700848 tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss;
849 dccp_inc_seqno(&tmp_seqno);
850 hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno;
851 dccp_inc_seqno(&tmp_seqno);
852 while (dccp_rx_hist_find_entry(&hcrx->ccid3hcrx_hist,
853 tmp_seqno, &ccval)) {
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200854 hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno;
Ian McDonald66a377c2006-08-26 23:40:50 -0700855 hcrx->ccid3hcrx_ccval_nonloss = ccval;
856 dccp_inc_seqno(&tmp_seqno);
857 }
858 }
859
860 /* FIXME - this code could be simplified with above while */
861 /* but works at moment */
862 if (follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) {
863 hcrx->ccid3hcrx_seqno_nonloss = seqno;
864 hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval;
865 }
866
867detect_out:
868 dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist,
869 &hcrx->ccid3hcrx_li_hist, packet,
870 hcrx->ccid3hcrx_seqno_nonloss);
871 return loss;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700872}
873
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700874static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
875{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300876 struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
Arnaldo Carvalho de Melo4fded332005-08-23 21:51:59 -0700877 const struct dccp_options_received *opt_recv;
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -0300878 struct dccp_rx_hist_entry *packet;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700879 struct timeval now;
Gerrit Renker7dfee1a2007-03-20 15:24:37 -0300880 u32 p_prev, r_sample, rtt_prev;
Gerrit Renker78ad7132006-11-28 19:22:33 -0200881 int loss, payload_size;
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300882
Gerrit Renker59348b12006-11-20 18:39:23 -0200883 BUG_ON(hcrx == NULL);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700884
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300885 opt_recv = &dccp_sk(sk)->dccps_options_received;
Arnaldo Carvalho de Melo4fded332005-08-23 21:51:59 -0700886
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700887 switch (DCCP_SKB_CB(skb)->dccpd_type) {
888 case DCCP_PKT_ACK:
889 if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)
890 return;
891 case DCCP_PKT_DATAACK:
Arnaldo Carvalho de Melo4fded332005-08-23 21:51:59 -0700892 if (opt_recv->dccpor_timestamp_echo == 0)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700893 break;
Ian McDonald66a377c2006-08-26 23:40:50 -0700894 rtt_prev = hcrx->ccid3hcrx_rtt;
Arnaldo Carvalho de Melob0e56782005-09-09 02:38:35 -0300895 dccp_timestamp(sk, &now);
Gerrit Renker7dfee1a2007-03-20 15:24:37 -0300896 r_sample = dccp_sample_rtt(sk, &now, NULL);
Arnaldo Carvalho de Melob3a30772005-09-09 02:34:10 -0300897
898 if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)
899 hcrx->ccid3hcrx_rtt = r_sample;
900 else
901 hcrx->ccid3hcrx_rtt = (hcrx->ccid3hcrx_rtt * 9) / 10 +
902 r_sample / 10;
903
Ian McDonald66a377c2006-08-26 23:40:50 -0700904 if (rtt_prev != hcrx->ccid3hcrx_rtt)
Gerrit Renkera9672412006-12-10 00:14:12 -0200905 ccid3_pr_debug("%s(%p), New RTT=%uus, elapsed time=%u\n",
906 dccp_role(sk), sk, hcrx->ccid3hcrx_rtt,
Arnaldo Carvalho de Melo4fded332005-08-23 21:51:59 -0700907 opt_recv->dccpor_elapsed_time);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700908 break;
909 case DCCP_PKT_DATA:
910 break;
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300911 default: /* We're not interested in other packet types, move along */
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700912 return;
913 }
914
Arnaldo Carvalho de Melob0e56782005-09-09 02:38:35 -0300915 packet = dccp_rx_hist_entry_new(ccid3_rx_hist, sk, opt_recv->dccpor_ndp,
Christoph Lameter54e6ecb2006-12-06 20:33:16 -0800916 skb, GFP_ATOMIC);
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300917 if (unlikely(packet == NULL)) {
Gerrit Renkera9672412006-12-10 00:14:12 -0200918 DCCP_WARN("%s(%p), Not enough mem to add rx packet "
Gerrit Renker59348b12006-11-20 18:39:23 -0200919 "to history, consider it lost!\n", dccp_role(sk), sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700920 return;
921 }
922
Ian McDonald66a377c2006-08-26 23:40:50 -0700923 loss = ccid3_hc_rx_detect_loss(sk, packet);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700924
925 if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK)
926 return;
927
Gerrit Renker78ad7132006-11-28 19:22:33 -0200928 payload_size = skb->len - dccp_hdr(skb)->dccph_doff * 4;
929 ccid3_hc_rx_update_s(hcrx, payload_size);
930
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700931 switch (hcrx->ccid3hcrx_state) {
932 case TFRC_RSTATE_NO_DATA:
Gerrit Renkera9672412006-12-10 00:14:12 -0200933 ccid3_pr_debug("%s(%p, state=%s), skb=%p, sending initial "
934 "feedback\n", dccp_role(sk), sk,
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -0300935 dccp_state_name(sk->sk_state), skb);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700936 ccid3_hc_rx_send_feedback(sk);
937 ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA);
938 return;
939 case TFRC_RSTATE_DATA:
Gerrit Renker78ad7132006-11-28 19:22:33 -0200940 hcrx->ccid3hcrx_bytes_recv += payload_size;
Ian McDonald66a377c2006-08-26 23:40:50 -0700941 if (loss)
Arnaldo Carvalho de Melob6ee3d42005-08-27 18:18:18 -0300942 break;
943
Arnaldo Carvalho de Melob0e56782005-09-09 02:38:35 -0300944 dccp_timestamp(sk, &now);
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -0200945 if ((timeval_delta(&now, &hcrx->ccid3hcrx_tstamp_last_ack) -
946 (suseconds_t)hcrx->ccid3hcrx_rtt) >= 0) {
Arnaldo Carvalho de Melob6ee3d42005-08-27 18:18:18 -0300947 hcrx->ccid3hcrx_tstamp_last_ack = now;
948 ccid3_hc_rx_send_feedback(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700949 }
Arnaldo Carvalho de Melob6ee3d42005-08-27 18:18:18 -0300950 return;
Gerrit Renker59348b12006-11-20 18:39:23 -0200951 case TFRC_RSTATE_TERM:
Gerrit Renkera9672412006-12-10 00:14:12 -0200952 DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700953 return;
954 }
955
956 /* Dealing with packet loss */
Gerrit Renkera9672412006-12-10 00:14:12 -0200957 ccid3_pr_debug("%s(%p, state=%s), data loss! Reacting...\n",
Arnaldo Carvalho de Melo4fded332005-08-23 21:51:59 -0700958 dccp_role(sk), sk, dccp_state_name(sk->sk_state));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700959
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700960 p_prev = hcrx->ccid3hcrx_p;
YOSHIFUJI Hideakic9eaf172007-02-09 23:24:38 +0900961
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700962 /* Calculate loss event rate */
Ian McDonaldc0996662006-03-03 17:54:46 -0800963 if (!list_empty(&hcrx->ccid3hcrx_li_hist)) {
964 u32 i_mean = dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist);
965
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700966 /* Scaling up by 1000000 as fixed decimal */
Ian McDonaldc0996662006-03-03 17:54:46 -0800967 if (i_mean != 0)
968 hcrx->ccid3hcrx_p = 1000000 / i_mean;
Gerrit Renker59348b12006-11-20 18:39:23 -0200969 } else
970 DCCP_BUG("empty loss history");
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700971
972 if (hcrx->ccid3hcrx_p > p_prev) {
973 ccid3_hc_rx_send_feedback(sk);
974 return;
975 }
976}
977
Arnaldo Carvalho de Melo91f0ebf2006-03-20 19:21:44 -0800978static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700979{
Arnaldo Carvalho de Melo91f0ebf2006-03-20 19:21:44 -0800980 struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700981
Gerrit Renkera9672412006-12-10 00:14:12 -0200982 ccid3_pr_debug("entry\n");
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700983
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700984 hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA;
985 INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist);
Arnaldo Carvalho de Meloae6706f2005-08-27 23:03:09 -0300986 INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist);
Arnaldo Carvalho de Melob0e56782005-09-09 02:38:35 -0300987 dccp_timestamp(sk, &hcrx->ccid3hcrx_tstamp_last_ack);
Arnaldo Carvalho de Melo954ee312005-09-09 02:37:05 -0300988 hcrx->ccid3hcrx_tstamp_last_feedback = hcrx->ccid3hcrx_tstamp_last_ack;
Gerrit Renker78ad7132006-11-28 19:22:33 -0200989 hcrx->ccid3hcrx_s = 0;
Gerrit Renkerfe0499a2006-12-10 00:06:01 -0200990 hcrx->ccid3hcrx_rtt = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700991 return 0;
992}
993
994static void ccid3_hc_rx_exit(struct sock *sk)
995{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -0300996 struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700997
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -0300998 BUG_ON(hcrx == NULL);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700999
1000 ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM);
1001
1002 /* Empty packet history */
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -03001003 dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001004
1005 /* Empty loss interval history */
Arnaldo Carvalho de Melocc4d6a32007-05-28 18:53:08 -03001006 dccp_li_hist_purge(&hcrx->ccid3hcrx_li_hist);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001007}
1008
Arnaldo Carvalho de Melo2babe1f2005-08-23 21:52:35 -07001009static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info)
1010{
Arnaldo Carvalho de Melo59725dc2005-09-09 02:40:58 -03001011 const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
Arnaldo Carvalho de Melo2babe1f2005-08-23 21:52:35 -07001012
Arnaldo Carvalho de Melo59c23532005-09-12 14:16:58 -07001013 /* Listen socks doesn't have a private CCID block */
1014 if (sk->sk_state == DCCP_LISTEN)
1015 return;
1016
Arnaldo Carvalho de Melo59d203f2005-09-09 20:01:25 -03001017 BUG_ON(hcrx == NULL);
Arnaldo Carvalho de Melo2babe1f2005-08-23 21:52:35 -07001018
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -02001019 info->tcpi_ca_state = hcrx->ccid3hcrx_state;
1020 info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1021 info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt;
Arnaldo Carvalho de Melo2babe1f2005-08-23 21:52:35 -07001022}
1023
Arnaldo Carvalho de Melo88f964d2005-09-18 00:19:32 -07001024static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len,
1025 u32 __user *optval, int __user *optlen)
1026{
1027 const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
1028 const void *val;
YOSHIFUJI Hideakic9eaf172007-02-09 23:24:38 +09001029
Arnaldo Carvalho de Melo88f964d2005-09-18 00:19:32 -07001030 /* Listen socks doesn't have a private CCID block */
1031 if (sk->sk_state == DCCP_LISTEN)
1032 return -EINVAL;
1033
1034 switch (optname) {
1035 case DCCP_SOCKOPT_CCID_RX_INFO:
1036 if (len < sizeof(hcrx->ccid3hcrx_tfrc))
1037 return -EINVAL;
1038 len = sizeof(hcrx->ccid3hcrx_tfrc);
1039 val = &hcrx->ccid3hcrx_tfrc;
1040 break;
1041 default:
1042 return -ENOPROTOOPT;
1043 }
1044
1045 if (put_user(len, optlen) || copy_to_user(optval, val, len))
1046 return -EFAULT;
1047
1048 return 0;
1049}
1050
Arnaldo Carvalho de Melo91f0ebf2006-03-20 19:21:44 -08001051static struct ccid_operations ccid3 = {
Ian McDonald3dd9a7c2006-09-22 14:26:44 +12001052 .ccid_id = DCCPC_CCID3,
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001053 .ccid_name = "ccid3",
1054 .ccid_owner = THIS_MODULE,
Arnaldo Carvalho de Melo91f0ebf2006-03-20 19:21:44 -08001055 .ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock),
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001056 .ccid_hc_tx_init = ccid3_hc_tx_init,
1057 .ccid_hc_tx_exit = ccid3_hc_tx_exit,
1058 .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet,
1059 .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent,
1060 .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv,
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001061 .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options,
Arnaldo Carvalho de Melo91f0ebf2006-03-20 19:21:44 -08001062 .ccid_hc_rx_obj_size = sizeof(struct ccid3_hc_rx_sock),
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001063 .ccid_hc_rx_init = ccid3_hc_rx_init,
1064 .ccid_hc_rx_exit = ccid3_hc_rx_exit,
1065 .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options,
1066 .ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv,
Arnaldo Carvalho de Melo2babe1f2005-08-23 21:52:35 -07001067 .ccid_hc_rx_get_info = ccid3_hc_rx_get_info,
1068 .ccid_hc_tx_get_info = ccid3_hc_tx_get_info,
Arnaldo Carvalho de Melo88f964d2005-09-18 00:19:32 -07001069 .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt,
1070 .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt,
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001071};
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -02001072
Gerrit Renker56724aa2006-11-20 18:28:09 -02001073#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001074module_param(ccid3_debug, int, 0444);
1075MODULE_PARM_DESC(ccid3_debug, "Enable debug messages");
Gerrit Renker56724aa2006-11-20 18:28:09 -02001076#endif
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001077
1078static __init int ccid3_module_init(void)
1079{
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -03001080 int rc = -ENOBUFS;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001081
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -03001082 ccid3_rx_hist = dccp_rx_hist_new("ccid3");
1083 if (ccid3_rx_hist == NULL)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001084 goto out;
1085
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -03001086 ccid3_tx_hist = dccp_tx_hist_new("ccid3");
1087 if (ccid3_tx_hist == NULL)
1088 goto out_free_rx;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001089
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001090 rc = ccid_register(&ccid3);
Arnaldo Carvalho de Melo8109b022006-12-10 16:01:18 -02001091 if (rc != 0)
Arnaldo Carvalho de Melocc4d6a32007-05-28 18:53:08 -03001092 goto out_free_tx;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001093out:
1094 return rc;
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -03001095
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -03001096out_free_tx:
1097 dccp_tx_hist_delete(ccid3_tx_hist);
1098 ccid3_tx_hist = NULL;
1099out_free_rx:
1100 dccp_rx_hist_delete(ccid3_rx_hist);
1101 ccid3_rx_hist = NULL;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001102 goto out;
1103}
1104module_init(ccid3_module_init);
1105
1106static __exit void ccid3_module_exit(void)
1107{
1108 ccid_unregister(&ccid3);
1109
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -03001110 if (ccid3_tx_hist != NULL) {
1111 dccp_tx_hist_delete(ccid3_tx_hist);
1112 ccid3_tx_hist = NULL;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001113 }
Arnaldo Carvalho de Melo8c60f3f2005-08-10 12:59:38 -03001114 if (ccid3_rx_hist != NULL) {
1115 dccp_rx_hist_delete(ccid3_rx_hist);
1116 ccid3_rx_hist = NULL;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001117 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001118}
1119module_exit(ccid3_module_exit);
1120
Ian McDonalde6bccd32006-08-26 19:01:30 -07001121MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>, "
Arnaldo Carvalho de Melo1f2333a2005-08-27 03:51:58 -03001122 "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>");
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001123MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID");
1124MODULE_LICENSE("GPL");
1125MODULE_ALIAS("net-dccp-ccid-3");