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-rw-r--r--net/dccp/feat.c504
-rw-r--r--net/dccp/feat.h12
2 files changed, 11 insertions, 505 deletions
diff --git a/net/dccp/feat.c b/net/dccp/feat.c
index b127189550f1..077f78d579c4 100644
--- a/net/dccp/feat.c
+++ b/net/dccp/feat.c
@@ -1,8 +1,12 @@
1/* 1/*
2 * net/dccp/feat.c 2 * net/dccp/feat.c
3 * 3 *
4 * An implementation of the DCCP protocol 4 * Feature negotiation for the DCCP protocol (RFC 4340, section 6)
5 * Andrea Bittau <a.bittau@cs.ucl.ac.uk> 5 *
6 * Copyright (c) 2008 Gerrit Renker <gerrit@erg.abdn.ac.uk>
7 * Rewrote from scratch, some bits from earlier code by
8 * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
9 *
6 * 10 *
7 * ASSUMPTIONS 11 * ASSUMPTIONS
8 * ----------- 12 * -----------
@@ -17,14 +21,10 @@
17 * as published by the Free Software Foundation; either version 21 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version. 22 * 2 of the License, or (at your option) any later version.
19 */ 23 */
20
21#include <linux/module.h> 24#include <linux/module.h>
22
23#include "ccid.h" 25#include "ccid.h"
24#include "feat.h" 26#include "feat.h"
25 27
26#define DCCP_FEAT_SP_NOAGREE (-123)
27
28/* 28/*
29 * Feature activation handlers. 29 * Feature activation handlers.
30 * 30 *
@@ -811,51 +811,6 @@ int dccp_feat_server_ccid_dependencies(struct dccp_request_sock *dreq)
811 return 0; 811 return 0;
812} 812}
813 813
814static int dccp_feat_update_ccid(struct sock *sk, u8 type, u8 new_ccid_nr)
815{
816 struct dccp_sock *dp = dccp_sk(sk);
817 struct dccp_minisock *dmsk = dccp_msk(sk);
818 /* figure out if we are changing our CCID or the peer's */
819 const int rx = type == DCCPO_CHANGE_R;
820 const u8 ccid_nr = rx ? dmsk->dccpms_rx_ccid : dmsk->dccpms_tx_ccid;
821 struct ccid *new_ccid;
822
823 /* Check if nothing is being changed. */
824 if (ccid_nr == new_ccid_nr)
825 return 0;
826
827 new_ccid = ccid_new(new_ccid_nr, sk, rx, GFP_ATOMIC);
828 if (new_ccid == NULL)
829 return -ENOMEM;
830
831 if (rx) {
832 ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
833 dp->dccps_hc_rx_ccid = new_ccid;
834 dmsk->dccpms_rx_ccid = new_ccid_nr;
835 } else {
836 ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
837 dp->dccps_hc_tx_ccid = new_ccid;
838 dmsk->dccpms_tx_ccid = new_ccid_nr;
839 }
840
841 return 0;
842}
843
844static int dccp_feat_update(struct sock *sk, u8 type, u8 feat, u8 val)
845{
846 dccp_feat_debug(type, feat, val);
847
848 switch (feat) {
849 case DCCPF_CCID:
850 return dccp_feat_update_ccid(sk, type, val);
851 default:
852 dccp_pr_debug("UNIMPLEMENTED: %s(%d, ...)\n",
853 dccp_feat_typename(type), feat);
854 break;
855 }
856 return 0;
857}
858
859/* Select the first entry in @servlist that also occurs in @clilist (6.3.1) */ 814/* Select the first entry in @servlist that also occurs in @clilist (6.3.1) */
860static int dccp_feat_preflist_match(u8 *servlist, u8 slen, u8 *clilist, u8 clen) 815static int dccp_feat_preflist_match(u8 *servlist, u8 slen, u8 *clilist, u8 clen)
861{ 816{
@@ -925,453 +880,6 @@ static int dccp_feat_reconcile(dccp_feat_val *fv, u8 *arr, u8 len,
925 return dccp_feat_prefer(rc, fv->sp.vec, fv->sp.len); 880 return dccp_feat_prefer(rc, fv->sp.vec, fv->sp.len);
926} 881}
927 882
928#ifdef __this_is_the_old_framework_and_will_be_removed_later_in_a_subsequent_patch
929static int dccp_feat_reconcile(struct sock *sk, struct dccp_opt_pend *opt,
930 u8 *rpref, u8 rlen)
931{
932 struct dccp_sock *dp = dccp_sk(sk);
933 u8 *spref, slen, *res = NULL;
934 int i, j, rc, agree = 1;
935
936 BUG_ON(rpref == NULL);
937
938 /* check if we are the black sheep */
939 if (dp->dccps_role == DCCP_ROLE_CLIENT) {
940 spref = rpref;
941 slen = rlen;
942 rpref = opt->dccpop_val;
943 rlen = opt->dccpop_len;
944 } else {
945 spref = opt->dccpop_val;
946 slen = opt->dccpop_len;
947 }
948 /*
949 * Now we have server preference list in spref and client preference in
950 * rpref
951 */
952 BUG_ON(spref == NULL);
953 BUG_ON(rpref == NULL);
954
955 /* FIXME sanity check vals */
956
957 /* Are values in any order? XXX Lame "algorithm" here */
958 for (i = 0; i < slen; i++) {
959 for (j = 0; j < rlen; j++) {
960 if (spref[i] == rpref[j]) {
961 res = &spref[i];
962 break;
963 }
964 }
965 if (res)
966 break;
967 }
968
969 /* we didn't agree on anything */
970 if (res == NULL) {
971 /* confirm previous value */
972 switch (opt->dccpop_feat) {
973 case DCCPF_CCID:
974 /* XXX did i get this right? =P */
975 if (opt->dccpop_type == DCCPO_CHANGE_L)
976 res = &dccp_msk(sk)->dccpms_tx_ccid;
977 else
978 res = &dccp_msk(sk)->dccpms_rx_ccid;
979 break;
980
981 default:
982 DCCP_BUG("Fell through, feat=%d", opt->dccpop_feat);
983 /* XXX implement res */
984 return -EFAULT;
985 }
986
987 dccp_pr_debug("Don't agree... reconfirming %d\n", *res);
988 agree = 0; /* this is used for mandatory options... */
989 }
990
991 /* need to put result and our preference list */
992 rlen = 1 + opt->dccpop_len;
993 rpref = kmalloc(rlen, GFP_ATOMIC);
994 if (rpref == NULL)
995 return -ENOMEM;
996
997 *rpref = *res;
998 memcpy(&rpref[1], opt->dccpop_val, opt->dccpop_len);
999
1000 /* put it in the "confirm queue" */
1001 if (opt->dccpop_sc == NULL) {
1002 opt->dccpop_sc = kmalloc(sizeof(*opt->dccpop_sc), GFP_ATOMIC);
1003 if (opt->dccpop_sc == NULL) {
1004 kfree(rpref);
1005 return -ENOMEM;
1006 }
1007 } else {
1008 /* recycle the confirm slot */
1009 BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
1010 kfree(opt->dccpop_sc->dccpoc_val);
1011 dccp_pr_debug("recycling confirm slot\n");
1012 }
1013 memset(opt->dccpop_sc, 0, sizeof(*opt->dccpop_sc));
1014
1015 opt->dccpop_sc->dccpoc_val = rpref;
1016 opt->dccpop_sc->dccpoc_len = rlen;
1017
1018 /* update the option on our side [we are about to send the confirm] */
1019 rc = dccp_feat_update(sk, opt->dccpop_type, opt->dccpop_feat, *res);
1020 if (rc) {
1021 kfree(opt->dccpop_sc->dccpoc_val);
1022 kfree(opt->dccpop_sc);
1023 opt->dccpop_sc = NULL;
1024 return rc;
1025 }
1026
1027 dccp_pr_debug("Will confirm %d\n", *rpref);
1028
1029 /* say we want to change to X but we just got a confirm X, suppress our
1030 * change
1031 */
1032 if (!opt->dccpop_conf) {
1033 if (*opt->dccpop_val == *res)
1034 opt->dccpop_conf = 1;
1035 dccp_pr_debug("won't ask for change of same feature\n");
1036 }
1037
1038 return agree ? 0 : DCCP_FEAT_SP_NOAGREE; /* used for mandatory opts */
1039}
1040
1041static int dccp_feat_sp(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
1042{
1043 struct dccp_minisock *dmsk = dccp_msk(sk);
1044 struct dccp_opt_pend *opt;
1045 int rc = 1;
1046 u8 t;
1047
1048 /*
1049 * We received a CHANGE. We gotta match it against our own preference
1050 * list. If we got a CHANGE_R it means it's a change for us, so we need
1051 * to compare our CHANGE_L list.
1052 */
1053 if (type == DCCPO_CHANGE_L)
1054 t = DCCPO_CHANGE_R;
1055 else
1056 t = DCCPO_CHANGE_L;
1057
1058 /* find our preference list for this feature */
1059 list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
1060 if (opt->dccpop_type != t || opt->dccpop_feat != feature)
1061 continue;
1062
1063 /* find the winner from the two preference lists */
1064 rc = dccp_feat_reconcile(sk, opt, val, len);
1065 break;
1066 }
1067
1068 /* We didn't deal with the change. This can happen if we have no
1069 * preference list for the feature. In fact, it just shouldn't
1070 * happen---if we understand a feature, we should have a preference list
1071 * with at least the default value.
1072 */
1073 BUG_ON(rc == 1);
1074
1075 return rc;
1076}
1077
1078static int dccp_feat_nn(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
1079{
1080 struct dccp_opt_pend *opt;
1081 struct dccp_minisock *dmsk = dccp_msk(sk);
1082 u8 *copy;
1083 int rc;
1084
1085 /* NN features must be Change L (sec. 6.3.2) */
1086 if (type != DCCPO_CHANGE_L) {
1087 dccp_pr_debug("received %s for NN feature %d\n",
1088 dccp_feat_typename(type), feature);
1089 return -EFAULT;
1090 }
1091
1092 /* XXX sanity check opt val */
1093
1094 /* copy option so we can confirm it */
1095 opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
1096 if (opt == NULL)
1097 return -ENOMEM;
1098
1099 copy = kmemdup(val, len, GFP_ATOMIC);
1100 if (copy == NULL) {
1101 kfree(opt);
1102 return -ENOMEM;
1103 }
1104
1105 opt->dccpop_type = DCCPO_CONFIRM_R; /* NN can only confirm R */
1106 opt->dccpop_feat = feature;
1107 opt->dccpop_val = copy;
1108 opt->dccpop_len = len;
1109
1110 /* change feature */
1111 rc = dccp_feat_update(sk, type, feature, *val);
1112 if (rc) {
1113 kfree(opt->dccpop_val);
1114 kfree(opt);
1115 return rc;
1116 }
1117
1118 dccp_feat_debug(type, feature, *copy);
1119
1120 list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf);
1121
1122 return 0;
1123}
1124
1125static void dccp_feat_empty_confirm(struct dccp_minisock *dmsk,
1126 u8 type, u8 feature)
1127{
1128 /* XXX check if other confirms for that are queued and recycle slot */
1129 struct dccp_opt_pend *opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
1130
1131 if (opt == NULL) {
1132 /* XXX what do we do? Ignoring should be fine. It's a change
1133 * after all =P
1134 */
1135 return;
1136 }
1137
1138 switch (type) {
1139 case DCCPO_CHANGE_L:
1140 opt->dccpop_type = DCCPO_CONFIRM_R;
1141 break;
1142 case DCCPO_CHANGE_R:
1143 opt->dccpop_type = DCCPO_CONFIRM_L;
1144 break;
1145 default:
1146 DCCP_WARN("invalid type %d\n", type);
1147 kfree(opt);
1148 return;
1149 }
1150 opt->dccpop_feat = feature;
1151 opt->dccpop_val = NULL;
1152 opt->dccpop_len = 0;
1153
1154 /* change feature */
1155 dccp_pr_debug("Empty %s(%d)\n", dccp_feat_typename(type), feature);
1156
1157 list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf);
1158}
1159
1160static void dccp_feat_flush_confirm(struct sock *sk)
1161{
1162 struct dccp_minisock *dmsk = dccp_msk(sk);
1163 /* Check if there is anything to confirm in the first place */
1164 int yes = !list_empty(&dmsk->dccpms_conf);
1165
1166 if (!yes) {
1167 struct dccp_opt_pend *opt;
1168
1169 list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
1170 if (opt->dccpop_conf) {
1171 yes = 1;
1172 break;
1173 }
1174 }
1175 }
1176
1177 if (!yes)
1178 return;
1179
1180 /* OK there is something to confirm... */
1181 /* XXX check if packet is in flight? Send delayed ack?? */
1182 if (sk->sk_state == DCCP_OPEN)
1183 dccp_send_ack(sk);
1184}
1185
1186int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
1187{
1188 int rc;
1189
1190 /* Ignore Change requests other than during connection setup */
1191 if (sk->sk_state != DCCP_LISTEN && sk->sk_state != DCCP_REQUESTING)
1192 return 0;
1193 dccp_feat_debug(type, feature, *val);
1194
1195 /* figure out if it's SP or NN feature */
1196 switch (feature) {
1197 /* deal with SP features */
1198 case DCCPF_CCID:
1199 /* XXX Obsoleted by next patch
1200 rc = dccp_feat_sp(sk, type, feature, val, len); */
1201 break;
1202
1203 /* deal with NN features */
1204 case DCCPF_ACK_RATIO:
1205 /* XXX Obsoleted by next patch
1206 rc = dccp_feat_nn(sk, type, feature, val, len); */
1207 break;
1208
1209 /* XXX implement other features */
1210 default:
1211 dccp_pr_debug("UNIMPLEMENTED: not handling %s(%d, ...)\n",
1212 dccp_feat_typename(type), feature);
1213 rc = -EFAULT;
1214 break;
1215 }
1216
1217 /* check if there were problems changing features */
1218 if (rc) {
1219 /* If we don't agree on SP, we sent a confirm for old value.
1220 * However we propagate rc to caller in case option was
1221 * mandatory
1222 */
1223 if (rc != DCCP_FEAT_SP_NOAGREE)
1224 dccp_feat_empty_confirm(dccp_msk(sk), type, feature);
1225 }
1226
1227 /* generate the confirm [if required] */
1228 dccp_feat_flush_confirm(sk);
1229
1230 return rc;
1231}
1232
1233EXPORT_SYMBOL_GPL(dccp_feat_change_recv);
1234
1235int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
1236 u8 *val, u8 len)
1237{
1238 u8 t;
1239 struct dccp_opt_pend *opt;
1240 struct dccp_minisock *dmsk = dccp_msk(sk);
1241 int found = 0;
1242 int all_confirmed = 1;
1243
1244 /* Ignore Confirm options other than during connection setup */
1245 if (sk->sk_state != DCCP_LISTEN && sk->sk_state != DCCP_REQUESTING)
1246 return 0;
1247 dccp_feat_debug(type, feature, *val);
1248
1249 /* locate our change request */
1250 switch (type) {
1251 case DCCPO_CONFIRM_L: t = DCCPO_CHANGE_R; break;
1252 case DCCPO_CONFIRM_R: t = DCCPO_CHANGE_L; break;
1253 default: DCCP_WARN("invalid type %d\n", type);
1254 return 1;
1255
1256 }
1257 /* XXX sanity check feature value */
1258
1259 list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
1260 if (!opt->dccpop_conf && opt->dccpop_type == t &&
1261 opt->dccpop_feat == feature) {
1262 found = 1;
1263 dccp_pr_debug("feature %d found\n", opt->dccpop_feat);
1264
1265 /* XXX do sanity check */
1266
1267 opt->dccpop_conf = 1;
1268
1269 /* We got a confirmation---change the option */
1270 dccp_feat_update(sk, opt->dccpop_type,
1271 opt->dccpop_feat, *val);
1272
1273 /* XXX check the return value of dccp_feat_update */
1274 break;
1275 }
1276
1277 if (!opt->dccpop_conf)
1278 all_confirmed = 0;
1279 }
1280
1281 if (!found)
1282 dccp_pr_debug("%s(%d, ...) never requested\n",
1283 dccp_feat_typename(type), feature);
1284 return 0;
1285}
1286
1287EXPORT_SYMBOL_GPL(dccp_feat_confirm_recv);
1288#endif /* (later) */
1289
1290void dccp_feat_clean(struct dccp_minisock *dmsk)
1291{
1292 struct dccp_opt_pend *opt, *next;
1293
1294 list_for_each_entry_safe(opt, next, &dmsk->dccpms_pending,
1295 dccpop_node) {
1296 BUG_ON(opt->dccpop_val == NULL);
1297 kfree(opt->dccpop_val);
1298
1299 if (opt->dccpop_sc != NULL) {
1300 BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
1301 kfree(opt->dccpop_sc->dccpoc_val);
1302 kfree(opt->dccpop_sc);
1303 }
1304
1305 kfree(opt);
1306 }
1307 INIT_LIST_HEAD(&dmsk->dccpms_pending);
1308
1309 list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) {
1310 BUG_ON(opt == NULL);
1311 if (opt->dccpop_val != NULL)
1312 kfree(opt->dccpop_val);
1313 kfree(opt);
1314 }
1315 INIT_LIST_HEAD(&dmsk->dccpms_conf);
1316}
1317
1318EXPORT_SYMBOL_GPL(dccp_feat_clean);
1319
1320/* this is to be called only when a listening sock creates its child. It is
1321 * assumed by the function---the confirm is not duplicated, but rather it is
1322 * "passed on".
1323 */
1324int dccp_feat_clone(struct sock *oldsk, struct sock *newsk)
1325{
1326 struct dccp_minisock *olddmsk = dccp_msk(oldsk);
1327 struct dccp_minisock *newdmsk = dccp_msk(newsk);
1328 struct dccp_opt_pend *opt;
1329 int rc = 0;
1330
1331 INIT_LIST_HEAD(&newdmsk->dccpms_pending);
1332 INIT_LIST_HEAD(&newdmsk->dccpms_conf);
1333
1334 list_for_each_entry(opt, &olddmsk->dccpms_pending, dccpop_node) {
1335 struct dccp_opt_pend *newopt;
1336 /* copy the value of the option */
1337 u8 *val = kmemdup(opt->dccpop_val, opt->dccpop_len, GFP_ATOMIC);
1338
1339 if (val == NULL)
1340 goto out_clean;
1341
1342 newopt = kmemdup(opt, sizeof(*newopt), GFP_ATOMIC);
1343 if (newopt == NULL) {
1344 kfree(val);
1345 goto out_clean;
1346 }
1347
1348 /* insert the option */
1349 newopt->dccpop_val = val;
1350 list_add_tail(&newopt->dccpop_node, &newdmsk->dccpms_pending);
1351
1352 /* XXX what happens with backlogs and multiple connections at
1353 * once...
1354 */
1355 /* the master socket no longer needs to worry about confirms */
1356 opt->dccpop_sc = NULL; /* it's not a memleak---new socket has it */
1357
1358 /* reset state for a new socket */
1359 opt->dccpop_conf = 0;
1360 }
1361
1362 /* XXX not doing anything about the conf queue */
1363
1364out:
1365 return rc;
1366
1367out_clean:
1368 dccp_feat_clean(newdmsk);
1369 rc = -ENOMEM;
1370 goto out;
1371}
1372
1373EXPORT_SYMBOL_GPL(dccp_feat_clone);
1374
1375/** 883/**
1376 * dccp_feat_change_recv - Process incoming ChangeL/R options 884 * dccp_feat_change_recv - Process incoming ChangeL/R options
1377 * @fn: feature-negotiation list to update 885 * @fn: feature-negotiation list to update
diff --git a/net/dccp/feat.h b/net/dccp/feat.h
index f749610ae383..9b46e2a7866e 100644
--- a/net/dccp/feat.h
+++ b/net/dccp/feat.h
@@ -3,14 +3,14 @@
3/* 3/*
4 * net/dccp/feat.h 4 * net/dccp/feat.h
5 * 5 *
6 * An implementation of the DCCP protocol 6 * Feature negotiation for the DCCP protocol (RFC 4340, section 6)
7 * Copyright (c) 2008 Gerrit Renker <gerrit@erg.abdn.ac.uk>
7 * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk> 8 * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
8 * 9 *
9 * This program is free software; you can redistribute it and/or modify it 10 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License version 2 as 11 * under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation. 12 * published by the Free Software Foundation.
12 */ 13 */
13
14#include <linux/types.h> 14#include <linux/types.h>
15#include "dccp.h" 15#include "dccp.h"
16 16
@@ -118,8 +118,6 @@ extern int dccp_feat_register_sp(struct sock *sk, u8 feat, u8 is_local,
118extern int dccp_feat_register_nn(struct sock *sk, u8 feat, u64 val); 118extern int dccp_feat_register_nn(struct sock *sk, u8 feat, u64 val);
119extern int dccp_feat_parse_options(struct sock *, struct dccp_request_sock *, 119extern int dccp_feat_parse_options(struct sock *, struct dccp_request_sock *,
120 u8 mand, u8 opt, u8 feat, u8 *val, u8 len); 120 u8 mand, u8 opt, u8 feat, u8 *val, u8 len);
121extern void dccp_feat_clean(struct dccp_minisock *dmsk);
122extern int dccp_feat_clone(struct sock *oldsk, struct sock *newsk);
123extern int dccp_feat_clone_list(struct list_head const *, struct list_head *); 121extern int dccp_feat_clone_list(struct list_head const *, struct list_head *);
124extern int dccp_feat_init(struct sock *sk); 122extern int dccp_feat_init(struct sock *sk);
125 123