/*
* net/dccp/feat.c
*
- * Feature negotiation for the DCCP protocol (RFC 4340, section 6)
- *
- * Copyright (c) 2008 The University of Aberdeen, Scotland, UK
- * Copyright (c) 2008 Gerrit Renker <gerrit@erg.abdn.ac.uk>
- * Rewrote from scratch, some bits from earlier code by
- * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
- *
+ * An implementation of the DCCP protocol
+ * Andrea Bittau <a.bittau@cs.ucl.ac.uk>
*
* ASSUMPTIONS
* -----------
- * o Feature negotiation is coordinated with connection setup (as in TCP), wild
- * changes of parameters of an established connection are not supported.
- * o Changing NN values (Ack Ratio only) is supported in state OPEN/PARTOPEN.
* o All currently known SP features have 1-byte quantities. If in the future
* extensions of RFCs 4340..42 define features with item lengths larger than
* one byte, a feature-specific extension of the code will be required.
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
+
#include <linux/module.h>
+
#include "ccid.h"
#include "feat.h"
-/* feature-specific sysctls - initialised to the defaults from RFC 4340, 6.4 */
-unsigned long sysctl_dccp_sequence_window __read_mostly = 100;
-int sysctl_dccp_rx_ccid __read_mostly = 2,
- sysctl_dccp_tx_ccid __read_mostly = 2;
+#define DCCP_FEAT_SP_NOAGREE (-123)
-/*
- * Feature activation handlers.
- *
- * These all use an u64 argument, to provide enough room for NN/SP features. At
- * this stage the negotiated values have been checked to be within their range.
- */
-static int dccp_hdlr_ccid(struct sock *sk, u64 ccid, bool rx)
+int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature,
+ u8 *val, u8 len, gfp_t gfp)
{
- struct dccp_sock *dp = dccp_sk(sk);
- struct ccid *new_ccid = ccid_new(ccid, sk, rx, gfp_any());
+ struct dccp_opt_pend *opt;
- if (new_ccid == NULL)
- return -ENOMEM;
+ dccp_feat_debug(type, feature, *val);
- if (rx) {
- ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
- dp->dccps_hc_rx_ccid = new_ccid;
- } else {
- ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
- dp->dccps_hc_tx_ccid = new_ccid;
+ if (len > 3) {
+ DCCP_WARN("invalid length %d\n", len);
+ return -EINVAL;
+ }
+ /* XXX add further sanity checks */
+
+ /* check if that feature is already being negotiated */
+ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
+ /* ok we found a negotiation for this option already */
+ if (opt->dccpop_feat == feature && opt->dccpop_type == type) {
+ dccp_pr_debug("Replacing old\n");
+ /* replace */
+ BUG_ON(opt->dccpop_val == NULL);
+ kfree(opt->dccpop_val);
+ opt->dccpop_val = val;
+ opt->dccpop_len = len;
+ opt->dccpop_conf = 0;
+ return 0;
+ }
}
- return 0;
-}
-static int dccp_hdlr_seq_win(struct sock *sk, u64 seq_win, bool rx)
-{
- struct dccp_sock *dp = dccp_sk(sk);
+ /* negotiation for a new feature */
+ opt = kmalloc(sizeof(*opt), gfp);
+ if (opt == NULL)
+ return -ENOMEM;
- if (rx) {
- dp->dccps_r_seq_win = seq_win;
- /* propagate changes to update SWL/SWH */
- dccp_update_gsr(sk, dp->dccps_gsr);
- } else {
- dp->dccps_l_seq_win = seq_win;
- /* propagate changes to update AWL */
- dccp_update_gss(sk, dp->dccps_gss);
- }
- return 0;
-}
+ opt->dccpop_type = type;
+ opt->dccpop_feat = feature;
+ opt->dccpop_len = len;
+ opt->dccpop_val = val;
+ opt->dccpop_conf = 0;
+ opt->dccpop_sc = NULL;
-static int dccp_hdlr_ack_ratio(struct sock *sk, u64 ratio, bool rx)
-{
-#ifndef __CCID2_COPES_GRACEFULLY_WITH_DYNAMIC_ACK_RATIO_UPDATES__
- /*
- * FIXME: This is required until several problems in the CCID-2 code are
- * resolved. The CCID-2 code currently does not cope well; using dynamic
- * Ack Ratios greater than 1 caused instabilities. These were manifest
- * in hangups and long RTO timeouts (1...3 seconds). Until this has been
- * stabilised, it is safer not to activate dynamic Ack Ratio changes.
- */
- dccp_pr_debug("Not changing %s Ack Ratio from 1 to %u\n",
- rx ? "RX" : "TX", (u16)ratio);
- ratio = 1;
-#endif
- if (rx)
- dccp_sk(sk)->dccps_r_ack_ratio = ratio;
- else
- dccp_sk(sk)->dccps_l_ack_ratio = ratio;
+ BUG_ON(opt->dccpop_val == NULL);
+
+ list_add_tail(&opt->dccpop_node, &dmsk->dccpms_pending);
return 0;
}
-static int dccp_hdlr_ackvec(struct sock *sk, u64 enable, bool rx)
+EXPORT_SYMBOL_GPL(dccp_feat_change);
+
+static int dccp_feat_update_ccid(struct sock *sk, u8 type, u8 new_ccid_nr)
{
struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ /* figure out if we are changing our CCID or the peer's */
+ const int rx = type == DCCPO_CHANGE_R;
+ const u8 ccid_nr = rx ? dmsk->dccpms_rx_ccid : dmsk->dccpms_tx_ccid;
+ struct ccid *new_ccid;
+
+ /* Check if nothing is being changed. */
+ if (ccid_nr == new_ccid_nr)
+ return 0;
+
+ new_ccid = ccid_new(new_ccid_nr, sk, rx, GFP_ATOMIC);
+ if (new_ccid == NULL)
+ return -ENOMEM;
if (rx) {
- if (enable && dp->dccps_hc_rx_ackvec == NULL) {
- dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(gfp_any());
- if (dp->dccps_hc_rx_ackvec == NULL)
- return -ENOMEM;
- } else if (!enable) {
- dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
- dp->dccps_hc_rx_ackvec = NULL;
- }
+ ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
+ dp->dccps_hc_rx_ccid = new_ccid;
+ dmsk->dccpms_rx_ccid = new_ccid_nr;
+ } else {
+ ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
+ dp->dccps_hc_tx_ccid = new_ccid;
+ dmsk->dccpms_tx_ccid = new_ccid_nr;
}
- return 0;
-}
-static int dccp_hdlr_ndp(struct sock *sk, u64 enable, bool rx)
-{
- if (!rx)
- dccp_sk(sk)->dccps_send_ndp_count = (enable > 0);
return 0;
}
-/*
- * Minimum Checksum Coverage is located at the RX side (9.2.1). This means that
- * `rx' holds when the sending peer informs about his partial coverage via a
- * ChangeR() option. In the other case, we are the sender and the receiver
- * announces its coverage via ChangeL() options. The policy here is to honour
- * such communication by enabling the corresponding partial coverage - but only
- * if it has not been set manually before; the warning here means that all
- * packets will be dropped.
- */
-static int dccp_hdlr_min_cscov(struct sock *sk, u64 cscov, bool rx)
+static int dccp_feat_update(struct sock *sk, u8 type, u8 feat, u8 val)
{
- struct dccp_sock *dp = dccp_sk(sk);
+ dccp_feat_debug(type, feat, val);
- if (rx)
- dp->dccps_pcrlen = cscov;
- else {
- if (dp->dccps_pcslen == 0)
- dp->dccps_pcslen = cscov;
- else if (cscov > dp->dccps_pcslen)
- DCCP_WARN("CsCov %u too small, peer requires >= %u\n",
- dp->dccps_pcslen, (u8)cscov);
+ switch (feat) {
+ case DCCPF_CCID:
+ return dccp_feat_update_ccid(sk, type, val);
+ default:
+ dccp_pr_debug("UNIMPLEMENTED: %s(%d, ...)\n",
+ dccp_feat_typename(type), feat);
+ break;
}
return 0;
}
-static const struct {
- u8 feat_num; /* DCCPF_xxx */
- enum dccp_feat_type rxtx; /* RX or TX */
- enum dccp_feat_type reconciliation; /* SP or NN */
- u8 default_value; /* as in 6.4 */
- int (*activation_hdlr)(struct sock *sk, u64 val, bool rx);
-/*
- * Lookup table for location and type of features (from RFC 4340/4342)
- * +--------------------------+----+-----+----+----+---------+-----------+
- * | Feature | Location | Reconc. | Initial | Section |
- * | | RX | TX | SP | NN | Value | Reference |
- * +--------------------------+----+-----+----+----+---------+-----------+
- * | DCCPF_CCID | | X | X | | 2 | 10 |
- * | DCCPF_SHORT_SEQNOS | | X | X | | 0 | 7.6.1 |
- * | DCCPF_SEQUENCE_WINDOW | | X | | X | 100 | 7.5.2 |
- * | DCCPF_ECN_INCAPABLE | X | | X | | 0 | 12.1 |
- * | DCCPF_ACK_RATIO | | X | | X | 2 | 11.3 |
- * | DCCPF_SEND_ACK_VECTOR | X | | X | | 0 | 11.5 |
- * | DCCPF_SEND_NDP_COUNT | | X | X | | 0 | 7.7.2 |
- * | DCCPF_MIN_CSUM_COVER | X | | X | | 0 | 9.2.1 |
- * | DCCPF_DATA_CHECKSUM | X | | X | | 0 | 9.3.1 |
- * | DCCPF_SEND_LEV_RATE | X | | X | | 0 | 4342/8.4 |
- * +--------------------------+----+-----+----+----+---------+-----------+
- */
-} dccp_feat_table[] = {
- { DCCPF_CCID, FEAT_AT_TX, FEAT_SP, 2, dccp_hdlr_ccid },
- { DCCPF_SHORT_SEQNOS, FEAT_AT_TX, FEAT_SP, 0, NULL },
- { DCCPF_SEQUENCE_WINDOW, FEAT_AT_TX, FEAT_NN, 100, dccp_hdlr_seq_win },
- { DCCPF_ECN_INCAPABLE, FEAT_AT_RX, FEAT_SP, 0, NULL },
- { DCCPF_ACK_RATIO, FEAT_AT_TX, FEAT_NN, 2, dccp_hdlr_ack_ratio},
- { DCCPF_SEND_ACK_VECTOR, FEAT_AT_RX, FEAT_SP, 0, dccp_hdlr_ackvec },
- { DCCPF_SEND_NDP_COUNT, FEAT_AT_TX, FEAT_SP, 0, dccp_hdlr_ndp },
- { DCCPF_MIN_CSUM_COVER, FEAT_AT_RX, FEAT_SP, 0, dccp_hdlr_min_cscov},
- { DCCPF_DATA_CHECKSUM, FEAT_AT_RX, FEAT_SP, 0, NULL },
- { DCCPF_SEND_LEV_RATE, FEAT_AT_RX, FEAT_SP, 0, NULL },
-};
-#define DCCP_FEAT_SUPPORTED_MAX ARRAY_SIZE(dccp_feat_table)
-
-/**
- * dccp_feat_index - Hash function to map feature number into array position
- * Returns consecutive array index or -1 if the feature is not understood.
- */
-static int dccp_feat_index(u8 feat_num)
+static int dccp_feat_reconcile(struct sock *sk, struct dccp_opt_pend *opt,
+ u8 *rpref, u8 rlen)
{
- /* The first 9 entries are occupied by the types from RFC 4340, 6.4 */
- if (feat_num > DCCPF_RESERVED && feat_num <= DCCPF_DATA_CHECKSUM)
- return feat_num - 1;
+ struct dccp_sock *dp = dccp_sk(sk);
+ u8 *spref, slen, *res = NULL;
+ int i, j, rc, agree = 1;
+ BUG_ON(rpref == NULL);
+
+ /* check if we are the black sheep */
+ if (dp->dccps_role == DCCP_ROLE_CLIENT) {
+ spref = rpref;
+ slen = rlen;
+ rpref = opt->dccpop_val;
+ rlen = opt->dccpop_len;
+ } else {
+ spref = opt->dccpop_val;
+ slen = opt->dccpop_len;
+ }
/*
- * Other features: add cases for new feature types here after adding
- * them to the above table.
+ * Now we have server preference list in spref and client preference in
+ * rpref
*/
- switch (feat_num) {
- case DCCPF_SEND_LEV_RATE:
- return DCCP_FEAT_SUPPORTED_MAX - 1;
- }
- return -1;
-}
-
-static u8 dccp_feat_type(u8 feat_num)
-{
- int idx = dccp_feat_index(feat_num);
-
- if (idx < 0)
- return FEAT_UNKNOWN;
- return dccp_feat_table[idx].reconciliation;
-}
+ BUG_ON(spref == NULL);
+ BUG_ON(rpref == NULL);
-static int dccp_feat_default_value(u8 feat_num)
-{
- int idx = dccp_feat_index(feat_num);
+ /* FIXME sanity check vals */
- return idx < 0 ? : dccp_feat_table[idx].default_value;
-}
-
-/*
- * Debugging and verbose-printing section
- */
-static const char *dccp_feat_fname(const u8 feat)
-{
- static const char *feature_names[] = {
- [DCCPF_RESERVED] = "Reserved",
- [DCCPF_CCID] = "CCID",
- [DCCPF_SHORT_SEQNOS] = "Allow Short Seqnos",
- [DCCPF_SEQUENCE_WINDOW] = "Sequence Window",
- [DCCPF_ECN_INCAPABLE] = "ECN Incapable",
- [DCCPF_ACK_RATIO] = "Ack Ratio",
- [DCCPF_SEND_ACK_VECTOR] = "Send ACK Vector",
- [DCCPF_SEND_NDP_COUNT] = "Send NDP Count",
- [DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage",
- [DCCPF_DATA_CHECKSUM] = "Send Data Checksum",
- };
- if (feat > DCCPF_DATA_CHECKSUM && feat < DCCPF_MIN_CCID_SPECIFIC)
- return feature_names[DCCPF_RESERVED];
-
- if (feat == DCCPF_SEND_LEV_RATE)
- return "Send Loss Event Rate";
- if (feat >= DCCPF_MIN_CCID_SPECIFIC)
- return "CCID-specific";
-
- return feature_names[feat];
-}
-
-static const char *dccp_feat_sname[] = { "DEFAULT", "INITIALISING", "CHANGING",
- "UNSTABLE", "STABLE" };
-
-#ifdef CONFIG_IP_DCCP_DEBUG
-static const char *dccp_feat_oname(const u8 opt)
-{
- switch (opt) {
- case DCCPO_CHANGE_L: return "Change_L";
- case DCCPO_CONFIRM_L: return "Confirm_L";
- case DCCPO_CHANGE_R: return "Change_R";
- case DCCPO_CONFIRM_R: return "Confirm_R";
+ /* Are values in any order? XXX Lame "algorithm" here */
+ for (i = 0; i < slen; i++) {
+ for (j = 0; j < rlen; j++) {
+ if (spref[i] == rpref[j]) {
+ res = &spref[i];
+ break;
+ }
+ }
+ if (res)
+ break;
}
- return NULL;
-}
-static void dccp_feat_printval(u8 feat_num, dccp_feat_val const *val)
-{
- u8 i, type = dccp_feat_type(feat_num);
-
- if (val == NULL || (type == FEAT_SP && val->sp.vec == NULL))
- dccp_pr_debug_cat("(NULL)");
- else if (type == FEAT_SP)
- for (i = 0; i < val->sp.len; i++)
- dccp_pr_debug_cat("%s%u", i ? " " : "", val->sp.vec[i]);
- else if (type == FEAT_NN)
- dccp_pr_debug_cat("%llu", (unsigned long long)val->nn);
- else
- dccp_pr_debug_cat("unknown type %u", type);
-}
-
-static void dccp_feat_printvals(u8 feat_num, u8 *list, u8 len)
-{
- u8 type = dccp_feat_type(feat_num);
- dccp_feat_val fval = { .sp.vec = list, .sp.len = len };
-
- if (type == FEAT_NN)
- fval.nn = dccp_decode_value_var(list, len);
- dccp_feat_printval(feat_num, &fval);
-}
+ /* we didn't agree on anything */
+ if (res == NULL) {
+ /* confirm previous value */
+ switch (opt->dccpop_feat) {
+ case DCCPF_CCID:
+ /* XXX did i get this right? =P */
+ if (opt->dccpop_type == DCCPO_CHANGE_L)
+ res = &dccp_msk(sk)->dccpms_tx_ccid;
+ else
+ res = &dccp_msk(sk)->dccpms_rx_ccid;
+ break;
-static void dccp_feat_print_entry(struct dccp_feat_entry const *entry)
-{
- dccp_debug(" * %s %s = ", entry->is_local ? "local" : "remote",
- dccp_feat_fname(entry->feat_num));
- dccp_feat_printval(entry->feat_num, &entry->val);
- dccp_pr_debug_cat(", state=%s %s\n", dccp_feat_sname[entry->state],
- entry->needs_confirm ? "(Confirm pending)" : "");
-}
+ default:
+ DCCP_BUG("Fell through, feat=%d", opt->dccpop_feat);
+ /* XXX implement res */
+ return -EFAULT;
+ }
-#define dccp_feat_print_opt(opt, feat, val, len, mandatory) do { \
- dccp_pr_debug("%s(%s, ", dccp_feat_oname(opt), dccp_feat_fname(feat));\
- dccp_feat_printvals(feat, val, len); \
- dccp_pr_debug_cat(") %s\n", mandatory ? "!" : ""); } while (0)
-
-#define dccp_feat_print_fnlist(fn_list) { \
- const struct dccp_feat_entry *___entry; \
- \
- dccp_pr_debug("List Dump:\n"); \
- list_for_each_entry(___entry, fn_list, node) \
- dccp_feat_print_entry(___entry); \
-}
-#else /* ! CONFIG_IP_DCCP_DEBUG */
-#define dccp_feat_print_opt(opt, feat, val, len, mandatory)
-#define dccp_feat_print_fnlist(fn_list)
-#endif
+ dccp_pr_debug("Don't agree... reconfirming %d\n", *res);
+ agree = 0; /* this is used for mandatory options... */
+ }
-static int __dccp_feat_activate(struct sock *sk, const int idx,
- const bool is_local, dccp_feat_val const *fval)
-{
- bool rx;
- u64 val;
+ /* need to put result and our preference list */
+ rlen = 1 + opt->dccpop_len;
+ rpref = kmalloc(rlen, GFP_ATOMIC);
+ if (rpref == NULL)
+ return -ENOMEM;
- if (idx < 0 || idx >= DCCP_FEAT_SUPPORTED_MAX)
- return -1;
- if (dccp_feat_table[idx].activation_hdlr == NULL)
- return 0;
+ *rpref = *res;
+ memcpy(&rpref[1], opt->dccpop_val, opt->dccpop_len);
- if (fval == NULL) {
- val = dccp_feat_table[idx].default_value;
- } else if (dccp_feat_table[idx].reconciliation == FEAT_SP) {
- if (fval->sp.vec == NULL) {
- /*
- * This can happen when an empty Confirm is sent
- * for an SP (i.e. known) feature. In this case
- * we would be using the default anyway.
- */
- DCCP_CRIT("Feature #%d undefined: using default", idx);
- val = dccp_feat_table[idx].default_value;
- } else {
- val = fval->sp.vec[0];
+ /* put it in the "confirm queue" */
+ if (opt->dccpop_sc == NULL) {
+ opt->dccpop_sc = kmalloc(sizeof(*opt->dccpop_sc), GFP_ATOMIC);
+ if (opt->dccpop_sc == NULL) {
+ kfree(rpref);
+ return -ENOMEM;
}
} else {
- val = fval->nn;
+ /* recycle the confirm slot */
+ BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
+ kfree(opt->dccpop_sc->dccpoc_val);
+ dccp_pr_debug("recycling confirm slot\n");
+ }
+ memset(opt->dccpop_sc, 0, sizeof(*opt->dccpop_sc));
+
+ opt->dccpop_sc->dccpoc_val = rpref;
+ opt->dccpop_sc->dccpoc_len = rlen;
+
+ /* update the option on our side [we are about to send the confirm] */
+ rc = dccp_feat_update(sk, opt->dccpop_type, opt->dccpop_feat, *res);
+ if (rc) {
+ kfree(opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc);
+ opt->dccpop_sc = NULL;
+ return rc;
}
- /* Location is RX if this is a local-RX or remote-TX feature */
- rx = (is_local == (dccp_feat_table[idx].rxtx == FEAT_AT_RX));
-
- dccp_debug(" -> activating %s %s, %sval=%llu\n", rx ? "RX" : "TX",
- dccp_feat_fname(dccp_feat_table[idx].feat_num),
- fval ? "" : "default ", (unsigned long long)val);
-
- return dccp_feat_table[idx].activation_hdlr(sk, val, rx);
-}
-
-/**
- * dccp_feat_activate - Activate feature value on socket
- * @sk: fully connected DCCP socket (after handshake is complete)
- * @feat_num: feature to activate, one of %dccp_feature_numbers
- * @local: whether local (1) or remote (0) @feat_num is meant
- * @fval: the value (SP or NN) to activate, or NULL to use the default value
- * For general use this function is preferable over __dccp_feat_activate().
- */
-static int dccp_feat_activate(struct sock *sk, u8 feat_num, bool local,
- dccp_feat_val const *fval)
-{
- return __dccp_feat_activate(sk, dccp_feat_index(feat_num), local, fval);
-}
-
-/* Test for "Req'd" feature (RFC 4340, 6.4) */
-static inline int dccp_feat_must_be_understood(u8 feat_num)
-{
- return feat_num == DCCPF_CCID || feat_num == DCCPF_SHORT_SEQNOS ||
- feat_num == DCCPF_SEQUENCE_WINDOW;
-}
+ dccp_pr_debug("Will confirm %d\n", *rpref);
-/* copy constructor, fval must not already contain allocated memory */
-static int dccp_feat_clone_sp_val(dccp_feat_val *fval, u8 const *val, u8 len)
-{
- fval->sp.len = len;
- if (fval->sp.len > 0) {
- fval->sp.vec = kmemdup(val, len, gfp_any());
- if (fval->sp.vec == NULL) {
- fval->sp.len = 0;
- return -ENOBUFS;
- }
+ /* say we want to change to X but we just got a confirm X, suppress our
+ * change
+ */
+ if (!opt->dccpop_conf) {
+ if (*opt->dccpop_val == *res)
+ opt->dccpop_conf = 1;
+ dccp_pr_debug("won't ask for change of same feature\n");
}
- return 0;
-}
-static void dccp_feat_val_destructor(u8 feat_num, dccp_feat_val *val)
-{
- if (unlikely(val == NULL))
- return;
- if (dccp_feat_type(feat_num) == FEAT_SP)
- kfree(val->sp.vec);
- memset(val, 0, sizeof(*val));
+ return agree ? 0 : DCCP_FEAT_SP_NOAGREE; /* used for mandatory opts */
}
-static struct dccp_feat_entry *
- dccp_feat_clone_entry(struct dccp_feat_entry const *original)
+static int dccp_feat_sp(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
{
- struct dccp_feat_entry *new;
- u8 type = dccp_feat_type(original->feat_num);
-
- if (type == FEAT_UNKNOWN)
- return NULL;
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ struct dccp_opt_pend *opt;
+ int rc = 1;
+ u8 t;
- new = kmemdup(original, sizeof(struct dccp_feat_entry), gfp_any());
- if (new == NULL)
- return NULL;
+ /*
+ * We received a CHANGE. We gotta match it against our own preference
+ * list. If we got a CHANGE_R it means it's a change for us, so we need
+ * to compare our CHANGE_L list.
+ */
+ if (type == DCCPO_CHANGE_L)
+ t = DCCPO_CHANGE_R;
+ else
+ t = DCCPO_CHANGE_L;
- if (type == FEAT_SP && dccp_feat_clone_sp_val(&new->val,
- original->val.sp.vec,
- original->val.sp.len)) {
- kfree(new);
- return NULL;
- }
- return new;
-}
+ /* find our preference list for this feature */
+ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
+ if (opt->dccpop_type != t || opt->dccpop_feat != feature)
+ continue;
-static void dccp_feat_entry_destructor(struct dccp_feat_entry *entry)
-{
- if (entry != NULL) {
- dccp_feat_val_destructor(entry->feat_num, &entry->val);
- kfree(entry);
+ /* find the winner from the two preference lists */
+ rc = dccp_feat_reconcile(sk, opt, val, len);
+ break;
}
-}
-/*
- * List management functions
- *
- * Feature negotiation lists rely on and maintain the following invariants:
- * - each feat_num in the list is known, i.e. we know its type and default value
- * - each feat_num/is_local combination is unique (old entries are overwritten)
- * - SP values are always freshly allocated
- * - list is sorted in increasing order of feature number (faster lookup)
- */
-static struct dccp_feat_entry *dccp_feat_list_lookup(struct list_head *fn_list,
- u8 feat_num, bool is_local)
-{
- struct dccp_feat_entry *entry;
+ /* We didn't deal with the change. This can happen if we have no
+ * preference list for the feature. In fact, it just shouldn't
+ * happen---if we understand a feature, we should have a preference list
+ * with at least the default value.
+ */
+ BUG_ON(rc == 1);
- list_for_each_entry(entry, fn_list, node)
- if (entry->feat_num == feat_num && entry->is_local == is_local)
- return entry;
- else if (entry->feat_num > feat_num)
- break;
- return NULL;
+ return rc;
}
-/**
- * dccp_feat_entry_new - Central list update routine (called by all others)
- * @head: list to add to
- * @feat: feature number
- * @local: whether the local (1) or remote feature with number @feat is meant
- * This is the only constructor and serves to ensure the above invariants.
- */
-static struct dccp_feat_entry *
- dccp_feat_entry_new(struct list_head *head, u8 feat, bool local)
+static int dccp_feat_nn(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
{
- struct dccp_feat_entry *entry;
-
- list_for_each_entry(entry, head, node)
- if (entry->feat_num == feat && entry->is_local == local) {
- dccp_feat_val_destructor(entry->feat_num, &entry->val);
- return entry;
- } else if (entry->feat_num > feat) {
- head = &entry->node;
- break;
- }
+ struct dccp_opt_pend *opt;
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ u8 *copy;
+ int rc;
- entry = kmalloc(sizeof(*entry), gfp_any());
- if (entry != NULL) {
- entry->feat_num = feat;
- entry->is_local = local;
- list_add_tail(&entry->node, head);
+ /* NN features must be Change L (sec. 6.3.2) */
+ if (type != DCCPO_CHANGE_L) {
+ dccp_pr_debug("received %s for NN feature %d\n",
+ dccp_feat_typename(type), feature);
+ return -EFAULT;
}
- return entry;
-}
-/**
- * dccp_feat_push_change - Add/overwrite a Change option in the list
- * @fn_list: feature-negotiation list to update
- * @feat: one of %dccp_feature_numbers
- * @local: whether local (1) or remote (0) @feat_num is meant
- * @needs_mandatory: whether to use Mandatory feature negotiation options
- * @fval: pointer to NN/SP value to be inserted (will be copied)
- */
-static int dccp_feat_push_change(struct list_head *fn_list, u8 feat, u8 local,
- u8 mandatory, dccp_feat_val *fval)
-{
- struct dccp_feat_entry *new = dccp_feat_entry_new(fn_list, feat, local);
+ /* XXX sanity check opt val */
- if (new == NULL)
+ /* copy option so we can confirm it */
+ opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
+ if (opt == NULL)
return -ENOMEM;
- new->feat_num = feat;
- new->is_local = local;
- new->state = FEAT_INITIALISING;
- new->needs_confirm = 0;
- new->empty_confirm = 0;
- new->val = *fval;
- new->needs_mandatory = mandatory;
+ copy = kmemdup(val, len, GFP_ATOMIC);
+ if (copy == NULL) {
+ kfree(opt);
+ return -ENOMEM;
+ }
- return 0;
-}
+ opt->dccpop_type = DCCPO_CONFIRM_R; /* NN can only confirm R */
+ opt->dccpop_feat = feature;
+ opt->dccpop_val = copy;
+ opt->dccpop_len = len;
-/**
- * dccp_feat_push_confirm - Add a Confirm entry to the FN list
- * @fn_list: feature-negotiation list to add to
- * @feat: one of %dccp_feature_numbers
- * @local: whether local (1) or remote (0) @feat_num is being confirmed
- * @fval: pointer to NN/SP value to be inserted or NULL
- * Returns 0 on success, a Reset code for further processing otherwise.
- */
-static int dccp_feat_push_confirm(struct list_head *fn_list, u8 feat, u8 local,
- dccp_feat_val *fval)
-{
- struct dccp_feat_entry *new = dccp_feat_entry_new(fn_list, feat, local);
+ /* change feature */
+ rc = dccp_feat_update(sk, type, feature, *val);
+ if (rc) {
+ kfree(opt->dccpop_val);
+ kfree(opt);
+ return rc;
+ }
- if (new == NULL)
- return DCCP_RESET_CODE_TOO_BUSY;
+ dccp_feat_debug(type, feature, *copy);
- new->feat_num = feat;
- new->is_local = local;
- new->state = FEAT_STABLE; /* transition in 6.6.2 */
- new->needs_confirm = 1;
- new->empty_confirm = (fval == NULL);
- new->val.nn = 0; /* zeroes the whole structure */
- if (!new->empty_confirm)
- new->val = *fval;
- new->needs_mandatory = 0;
+ list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf);
return 0;
}
-static int dccp_push_empty_confirm(struct list_head *fn_list, u8 feat, u8 local)
+static void dccp_feat_empty_confirm(struct dccp_minisock *dmsk,
+ u8 type, u8 feature)
{
- return dccp_feat_push_confirm(fn_list, feat, local, NULL);
-}
+ /* XXX check if other confirms for that are queued and recycle slot */
+ struct dccp_opt_pend *opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
-static inline void dccp_feat_list_pop(struct dccp_feat_entry *entry)
-{
- list_del(&entry->node);
- dccp_feat_entry_destructor(entry);
-}
-
-void dccp_feat_list_purge(struct list_head *fn_list)
-{
- struct dccp_feat_entry *entry, *next;
-
- list_for_each_entry_safe(entry, next, fn_list, node)
- dccp_feat_entry_destructor(entry);
- INIT_LIST_HEAD(fn_list);
-}
-EXPORT_SYMBOL_GPL(dccp_feat_list_purge);
-
-/* generate @to as full clone of @from - @to must not contain any nodes */
-int dccp_feat_clone_list(struct list_head const *from, struct list_head *to)
-{
- struct dccp_feat_entry *entry, *new;
-
- INIT_LIST_HEAD(to);
- list_for_each_entry(entry, from, node) {
- new = dccp_feat_clone_entry(entry);
- if (new == NULL)
- goto cloning_failed;
- list_add_tail(&new->node, to);
+ if (opt == NULL) {
+ /* XXX what do we do? Ignoring should be fine. It's a change
+ * after all =P
+ */
+ return;
}
- return 0;
-cloning_failed:
- dccp_feat_list_purge(to);
- return -ENOMEM;
-}
+ switch (type) {
+ case DCCPO_CHANGE_L:
+ opt->dccpop_type = DCCPO_CONFIRM_R;
+ break;
+ case DCCPO_CHANGE_R:
+ opt->dccpop_type = DCCPO_CONFIRM_L;
+ break;
+ default:
+ DCCP_WARN("invalid type %d\n", type);
+ kfree(opt);
+ return;
+ }
+ opt->dccpop_feat = feature;
+ opt->dccpop_val = NULL;
+ opt->dccpop_len = 0;
-/**
- * dccp_feat_valid_nn_length - Enforce length constraints on NN options
- * Length is between 0 and %DCCP_OPTVAL_MAXLEN. Used for outgoing packets only,
- * incoming options are accepted as long as their values are valid.
- */
-static u8 dccp_feat_valid_nn_length(u8 feat_num)
-{
- if (feat_num == DCCPF_ACK_RATIO) /* RFC 4340, 11.3 and 6.6.8 */
- return 2;
- if (feat_num == DCCPF_SEQUENCE_WINDOW) /* RFC 4340, 7.5.2 and 6.5 */
- return 6;
- return 0;
-}
+ /* change feature */
+ dccp_pr_debug("Empty %s(%d)\n", dccp_feat_typename(type), feature);
-static u8 dccp_feat_is_valid_nn_val(u8 feat_num, u64 val)
-{
- switch (feat_num) {
- case DCCPF_ACK_RATIO:
- return val <= DCCPF_ACK_RATIO_MAX;
- case DCCPF_SEQUENCE_WINDOW:
- return val >= DCCPF_SEQ_WMIN && val <= DCCPF_SEQ_WMAX;
- }
- return 0; /* feature unknown - so we can't tell */
+ list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf);
}
-/* check that SP values are within the ranges defined in RFC 4340 */
-static u8 dccp_feat_is_valid_sp_val(u8 feat_num, u8 val)
+static void dccp_feat_flush_confirm(struct sock *sk)
{
- switch (feat_num) {
- case DCCPF_CCID:
- return val == DCCPC_CCID2 || val == DCCPC_CCID3;
- /* Type-check Boolean feature values: */
- case DCCPF_SHORT_SEQNOS:
- case DCCPF_ECN_INCAPABLE:
- case DCCPF_SEND_ACK_VECTOR:
- case DCCPF_SEND_NDP_COUNT:
- case DCCPF_DATA_CHECKSUM:
- case DCCPF_SEND_LEV_RATE:
- return val < 2;
- case DCCPF_MIN_CSUM_COVER:
- return val < 16;
- }
- return 0; /* feature unknown */
-}
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ /* Check if there is anything to confirm in the first place */
+ int yes = !list_empty(&dmsk->dccpms_conf);
-static u8 dccp_feat_sp_list_ok(u8 feat_num, u8 const *sp_list, u8 sp_len)
-{
- if (sp_list == NULL || sp_len < 1)
- return 0;
- while (sp_len--)
- if (!dccp_feat_is_valid_sp_val(feat_num, *sp_list++))
- return 0;
- return 1;
-}
+ if (!yes) {
+ struct dccp_opt_pend *opt;
-/**
- * dccp_feat_insert_opts - Generate FN options from current list state
- * @skb: next sk_buff to be sent to the peer
- * @dp: for client during handshake and general negotiation
- * @dreq: used by the server only (all Changes/Confirms in LISTEN/RESPOND)
- */
-int dccp_feat_insert_opts(struct dccp_sock *dp, struct dccp_request_sock *dreq,
- struct sk_buff *skb)
-{
- struct list_head *fn = dreq ? &dreq->dreq_featneg : &dp->dccps_featneg;
- struct dccp_feat_entry *pos, *next;
- u8 opt, type, len, *ptr, nn_in_nbo[DCCP_OPTVAL_MAXLEN];
- bool rpt;
-
- /* put entries into @skb in the order they appear in the list */
- list_for_each_entry_safe_reverse(pos, next, fn, node) {
- opt = dccp_feat_genopt(pos);
- type = dccp_feat_type(pos->feat_num);
- rpt = false;
-
- if (pos->empty_confirm) {
- len = 0;
- ptr = NULL;
- } else {
- if (type == FEAT_SP) {
- len = pos->val.sp.len;
- ptr = pos->val.sp.vec;
- rpt = pos->needs_confirm;
- } else if (type == FEAT_NN) {
- len = dccp_feat_valid_nn_length(pos->feat_num);
- ptr = nn_in_nbo;
- dccp_encode_value_var(pos->val.nn, ptr, len);
- } else {
- DCCP_BUG("unknown feature %u", pos->feat_num);
- return -1;
+ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
+ if (opt->dccpop_conf) {
+ yes = 1;
+ break;
}
}
- dccp_feat_print_opt(opt, pos->feat_num, ptr, len, 0);
-
- if (dccp_insert_fn_opt(skb, opt, pos->feat_num, ptr, len, rpt))
- return -1;
- if (pos->needs_mandatory && dccp_insert_option_mandatory(skb))
- return -1;
- /*
- * Enter CHANGING after transmitting the Change option (6.6.2).
- */
- if (pos->state == FEAT_INITIALISING)
- pos->state = FEAT_CHANGING;
}
- return 0;
-}
-
-/**
- * __feat_register_nn - Register new NN value on socket
- * @fn: feature-negotiation list to register with
- * @feat: an NN feature from %dccp_feature_numbers
- * @mandatory: use Mandatory option if 1
- * @nn_val: value to register (restricted to 4 bytes)
- * Note that NN features are local by definition (RFC 4340, 6.3.2).
- */
-static int __feat_register_nn(struct list_head *fn, u8 feat,
- u8 mandatory, u64 nn_val)
-{
- dccp_feat_val fval = { .nn = nn_val };
-
- if (dccp_feat_type(feat) != FEAT_NN ||
- !dccp_feat_is_valid_nn_val(feat, nn_val))
- return -EINVAL;
-
- /* Don't bother with default values, they will be activated anyway. */
- if (nn_val - (u64)dccp_feat_default_value(feat) == 0)
- return 0;
-
- return dccp_feat_push_change(fn, feat, 1, mandatory, &fval);
-}
-
-/**
- * __feat_register_sp - Register new SP value/list on socket
- * @fn: feature-negotiation list to register with
- * @feat: an SP feature from %dccp_feature_numbers
- * @is_local: whether the local (1) or the remote (0) @feat is meant
- * @mandatory: use Mandatory option if 1
- * @sp_val: SP value followed by optional preference list
- * @sp_len: length of @sp_val in bytes
- */
-static int __feat_register_sp(struct list_head *fn, u8 feat, u8 is_local,
- u8 mandatory, u8 const *sp_val, u8 sp_len)
-{
- dccp_feat_val fval;
- if (dccp_feat_type(feat) != FEAT_SP ||
- !dccp_feat_sp_list_ok(feat, sp_val, sp_len))
- return -EINVAL;
-
- /* Avoid negotiating alien CCIDs by only advertising supported ones */
- if (feat == DCCPF_CCID && !ccid_support_check(sp_val, sp_len))
- return -EOPNOTSUPP;
-
- if (dccp_feat_clone_sp_val(&fval, sp_val, sp_len))
- return -ENOMEM;
+ if (!yes)
+ return;
- return dccp_feat_push_change(fn, feat, is_local, mandatory, &fval);
+ /* OK there is something to confirm... */
+ /* XXX check if packet is in flight? Send delayed ack?? */
+ if (sk->sk_state == DCCP_OPEN)
+ dccp_send_ack(sk);
}
-/**
- * dccp_feat_register_sp - Register requests to change SP feature values
- * @sk: client or listening socket
- * @feat: one of %dccp_feature_numbers
- * @is_local: whether the local (1) or remote (0) @feat is meant
- * @list: array of preferred values, in descending order of preference
- * @len: length of @list in bytes
- */
-int dccp_feat_register_sp(struct sock *sk, u8 feat, u8 is_local,
- u8 const *list, u8 len)
-{ /* any changes must be registered before establishing the connection */
- if (sk->sk_state != DCCP_CLOSED)
- return -EISCONN;
- if (dccp_feat_type(feat) != FEAT_SP)
- return -EINVAL;
- return __feat_register_sp(&dccp_sk(sk)->dccps_featneg, feat, is_local,
- 0, list, len);
-}
-
-/* Analogous to dccp_feat_register_sp(), but for non-negotiable values */
-int dccp_feat_register_nn(struct sock *sk, u8 feat, u64 val)
+int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
{
- /* any changes must be registered before establishing the connection */
- if (sk->sk_state != DCCP_CLOSED)
- return -EISCONN;
- if (dccp_feat_type(feat) != FEAT_NN)
- return -EINVAL;
- return __feat_register_nn(&dccp_sk(sk)->dccps_featneg, feat, 0, val);
-}
+ int rc;
-/**
- * dccp_feat_signal_nn_change - Update NN values for an established connection
- * @sk: DCCP socket of an established connection
- * @feat: NN feature number from %dccp_feature_numbers
- * @nn_val: the new value to use
- * This function is used to communicate NN updates out-of-band. The difference
- * to feature negotiation during connection setup is that values are activated
- * immediately after validation, i.e. we don't wait for the Confirm: either the
- * value is accepted by the peer (and then the waiting is futile), or it is not
- * (Reset or empty Confirm). We don't accept empty Confirms - transmitted values
- * are validated, and the peer "MUST accept any valid value" (RFC 4340, 6.3.2).
- */
-int dccp_feat_signal_nn_change(struct sock *sk, u8 feat, u64 nn_val)
-{
- struct list_head *fn = &dccp_sk(sk)->dccps_featneg;
- dccp_feat_val fval = { .nn = nn_val };
- struct dccp_feat_entry *entry;
+ dccp_feat_debug(type, feature, *val);
- if (sk->sk_state != DCCP_OPEN && sk->sk_state != DCCP_PARTOPEN)
- return 0;
+ /* figure out if it's SP or NN feature */
+ switch (feature) {
+ /* deal with SP features */
+ case DCCPF_CCID:
+ rc = dccp_feat_sp(sk, type, feature, val, len);
+ break;
- if (dccp_feat_type(feat) != FEAT_NN ||
- !dccp_feat_is_valid_nn_val(feat, nn_val))
- return -EINVAL;
+ /* deal with NN features */
+ case DCCPF_ACK_RATIO:
+ rc = dccp_feat_nn(sk, type, feature, val, len);
+ break;
- entry = dccp_feat_list_lookup(fn, feat, 1);
- if (entry != NULL) {
- dccp_pr_debug("Ignoring %llu, entry %llu exists in state %s\n",
- (unsigned long long)nn_val,
- (unsigned long long)entry->val.nn,
- dccp_feat_sname[entry->state]);
- return 0;
+ /* XXX implement other features */
+ default:
+ dccp_pr_debug("UNIMPLEMENTED: not handling %s(%d, ...)\n",
+ dccp_feat_typename(type), feature);
+ rc = -EFAULT;
+ break;
}
- if (dccp_feat_activate(sk, feat, 1, &fval))
- return -EADV;
-
- inet_csk_schedule_ack(sk);
- return dccp_feat_push_change(fn, feat, 1, 0, &fval);
-}
-EXPORT_SYMBOL_GPL(dccp_feat_signal_nn_change);
-
-/*
- * Tracking features whose value depend on the choice of CCID
- *
- * This is designed with an extension in mind so that a list walk could be done
- * before activating any features. However, the existing framework was found to
- * work satisfactorily up until now, the automatic verification is left open.
- * When adding new CCIDs, add a corresponding dependency table here.
- */
-static const struct ccid_dependency *dccp_feat_ccid_deps(u8 ccid, bool is_local)
-{
- static const struct ccid_dependency ccid2_dependencies[2][2] = {
- /*
- * CCID2 mandates Ack Vectors (RFC 4341, 4.): as CCID is a TX
- * feature and Send Ack Vector is an RX feature, `is_local'
- * needs to be reversed.
+ /* check if there were problems changing features */
+ if (rc) {
+ /* If we don't agree on SP, we sent a confirm for old value.
+ * However we propagate rc to caller in case option was
+ * mandatory
*/
- { /* Dependencies of the receiver-side (remote) CCID2 */
- {
- .dependent_feat = DCCPF_SEND_ACK_VECTOR,
- .is_local = true,
- .is_mandatory = true,
- .val = 1
- },
- { 0, 0, 0, 0 }
- },
- { /* Dependencies of the sender-side (local) CCID2 */
- {
- .dependent_feat = DCCPF_SEND_ACK_VECTOR,
- .is_local = false,
- .is_mandatory = true,
- .val = 1
- },
- { 0, 0, 0, 0 }
- }
- };
- static const struct ccid_dependency ccid3_dependencies[2][5] = {
- { /*
- * Dependencies of the receiver-side CCID3
- */
- { /* locally disable Ack Vectors */
- .dependent_feat = DCCPF_SEND_ACK_VECTOR,
- .is_local = true,
- .is_mandatory = false,
- .val = 0
- },
- { /* see below why Send Loss Event Rate is on */
- .dependent_feat = DCCPF_SEND_LEV_RATE,
- .is_local = true,
- .is_mandatory = true,
- .val = 1
- },
- { /* NDP Count is needed as per RFC 4342, 6.1.1 */
- .dependent_feat = DCCPF_SEND_NDP_COUNT,
- .is_local = false,
- .is_mandatory = true,
- .val = 1
- },
- { 0, 0, 0, 0 },
- },
- { /*
- * CCID3 at the TX side: we request that the HC-receiver
- * will not send Ack Vectors (they will be ignored, so
- * Mandatory is not set); we enable Send Loss Event Rate
- * (Mandatory since the implementation does not support
- * the Loss Intervals option of RFC 4342, 8.6).
- * The last two options are for peer's information only.
- */
- {
- .dependent_feat = DCCPF_SEND_ACK_VECTOR,
- .is_local = false,
- .is_mandatory = false,
- .val = 0
- },
- {
- .dependent_feat = DCCPF_SEND_LEV_RATE,
- .is_local = false,
- .is_mandatory = true,
- .val = 1
- },
- { /* this CCID does not support Ack Ratio */
- .dependent_feat = DCCPF_ACK_RATIO,
- .is_local = true,
- .is_mandatory = false,
- .val = 0
- },
- { /* tell receiver we are sending NDP counts */
- .dependent_feat = DCCPF_SEND_NDP_COUNT,
- .is_local = true,
- .is_mandatory = false,
- .val = 1
- },
- { 0, 0, 0, 0 }
- }
- };
- switch (ccid) {
- case DCCPC_CCID2:
- return ccid2_dependencies[is_local];
- case DCCPC_CCID3:
- return ccid3_dependencies[is_local];
- default:
- return NULL;
+ if (rc != DCCP_FEAT_SP_NOAGREE)
+ dccp_feat_empty_confirm(dccp_msk(sk), type, feature);
}
-}
-/**
- * dccp_feat_propagate_ccid - Resolve dependencies of features on choice of CCID
- * @fn: feature-negotiation list to update
- * @id: CCID number to track
- * @is_local: whether TX CCID (1) or RX CCID (0) is meant
- * This function needs to be called after registering all other features.
- */
-static int dccp_feat_propagate_ccid(struct list_head *fn, u8 id, bool is_local)
-{
- const struct ccid_dependency *table = dccp_feat_ccid_deps(id, is_local);
- int i, rc = (table == NULL);
-
- for (i = 0; rc == 0 && table[i].dependent_feat != DCCPF_RESERVED; i++)
- if (dccp_feat_type(table[i].dependent_feat) == FEAT_SP)
- rc = __feat_register_sp(fn, table[i].dependent_feat,
- table[i].is_local,
- table[i].is_mandatory,
- &table[i].val, 1);
- else
- rc = __feat_register_nn(fn, table[i].dependent_feat,
- table[i].is_mandatory,
- table[i].val);
- return rc;
-}
-
-/**
- * dccp_feat_finalise_settings - Finalise settings before starting negotiation
- * @dp: client or listening socket (settings will be inherited)
- * This is called after all registrations (socket initialisation, sysctls, and
- * sockopt calls), and before sending the first packet containing Change options
- * (ie. client-Request or server-Response), to ensure internal consistency.
- */
-int dccp_feat_finalise_settings(struct dccp_sock *dp)
-{
- struct list_head *fn = &dp->dccps_featneg;
- struct dccp_feat_entry *entry;
- int i = 2, ccids[2] = { -1, -1 };
+ /* generate the confirm [if required] */
+ dccp_feat_flush_confirm(sk);
- /*
- * Propagating CCIDs:
- * 1) not useful to propagate CCID settings if this host advertises more
- * than one CCID: the choice of CCID may still change - if this is
- * the client, or if this is the server and the client sends
- * singleton CCID values.
- * 2) since is that propagate_ccid changes the list, we defer changing
- * the sorted list until after the traversal.
- */
- list_for_each_entry(entry, fn, node)
- if (entry->feat_num == DCCPF_CCID && entry->val.sp.len == 1)
- ccids[entry->is_local] = entry->val.sp.vec[0];
- while (i--)
- if (ccids[i] > 0 && dccp_feat_propagate_ccid(fn, ccids[i], i))
- return -1;
- dccp_feat_print_fnlist(fn);
- return 0;
+ return rc;
}
-/**
- * dccp_feat_server_ccid_dependencies - Resolve CCID-dependent features
- * It is the server which resolves the dependencies once the CCID has been
- * fully negotiated. If no CCID has been negotiated, it uses the default CCID.
- */
-int dccp_feat_server_ccid_dependencies(struct dccp_request_sock *dreq)
-{
- struct list_head *fn = &dreq->dreq_featneg;
- struct dccp_feat_entry *entry;
- u8 is_local, ccid;
-
- for (is_local = 0; is_local <= 1; is_local++) {
- entry = dccp_feat_list_lookup(fn, DCCPF_CCID, is_local);
-
- if (entry != NULL && !entry->empty_confirm)
- ccid = entry->val.sp.vec[0];
- else
- ccid = dccp_feat_default_value(DCCPF_CCID);
-
- if (dccp_feat_propagate_ccid(fn, ccid, is_local))
- return -1;
- }
- return 0;
-}
+EXPORT_SYMBOL_GPL(dccp_feat_change_recv);
-/* Select the first entry in @servlist that also occurs in @clilist (6.3.1) */
-static int dccp_feat_preflist_match(u8 *servlist, u8 slen, u8 *clilist, u8 clen)
+int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
+ u8 *val, u8 len)
{
- u8 c, s;
+ u8 t;
+ struct dccp_opt_pend *opt;
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ int found = 0;
+ int all_confirmed = 1;
- for (s = 0; s < slen; s++)
- for (c = 0; c < clen; c++)
- if (servlist[s] == clilist[c])
- return servlist[s];
- return -1;
-}
+ dccp_feat_debug(type, feature, *val);
-/**
- * dccp_feat_prefer - Move preferred entry to the start of array
- * Reorder the @array_len elements in @array so that @preferred_value comes
- * first. Returns >0 to indicate that @preferred_value does occur in @array.
- */
-static u8 dccp_feat_prefer(u8 preferred_value, u8 *array, u8 array_len)
-{
- u8 i, does_occur = 0;
+ /* locate our change request */
+ switch (type) {
+ case DCCPO_CONFIRM_L: t = DCCPO_CHANGE_R; break;
+ case DCCPO_CONFIRM_R: t = DCCPO_CHANGE_L; break;
+ default: DCCP_WARN("invalid type %d\n", type);
+ return 1;
- if (array != NULL) {
- for (i = 0; i < array_len; i++)
- if (array[i] == preferred_value) {
- array[i] = array[0];
- does_occur++;
- }
- if (does_occur)
- array[0] = preferred_value;
}
- return does_occur;
-}
+ /* XXX sanity check feature value */
-/**
- * dccp_feat_reconcile - Reconcile SP preference lists
- * @fval: SP list to reconcile into
- * @arr: received SP preference list
- * @len: length of @arr in bytes
- * @is_server: whether this side is the server (and @fv is the server's list)
- * @reorder: whether to reorder the list in @fv after reconciling with @arr
- * When successful, > 0 is returned and the reconciled list is in @fval.
- * A value of 0 means that negotiation failed (no shared entry).
- */
-static int dccp_feat_reconcile(dccp_feat_val *fv, u8 *arr, u8 len,
- bool is_server, bool reorder)
-{
- int rc;
+ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
+ if (!opt->dccpop_conf && opt->dccpop_type == t &&
+ opt->dccpop_feat == feature) {
+ found = 1;
+ dccp_pr_debug("feature %d found\n", opt->dccpop_feat);
- if (!fv->sp.vec || !arr) {
- DCCP_CRIT("NULL feature value or array");
- return 0;
- }
+ /* XXX do sanity check */
- if (is_server)
- rc = dccp_feat_preflist_match(fv->sp.vec, fv->sp.len, arr, len);
- else
- rc = dccp_feat_preflist_match(arr, len, fv->sp.vec, fv->sp.len);
-
- if (!reorder)
- return rc;
- if (rc < 0)
- return 0;
+ opt->dccpop_conf = 1;
- /*
- * Reorder list: used for activating features and in dccp_insert_fn_opt.
- */
- return dccp_feat_prefer(rc, fv->sp.vec, fv->sp.len);
-}
+ /* We got a confirmation---change the option */
+ dccp_feat_update(sk, opt->dccpop_type,
+ opt->dccpop_feat, *val);
-/**
- * dccp_feat_change_recv - Process incoming ChangeL/R options
- * @fn: feature-negotiation list to update
- * @is_mandatory: whether the Change was preceded by a Mandatory option
- * @opt: %DCCPO_CHANGE_L or %DCCPO_CHANGE_R
- * @feat: one of %dccp_feature_numbers
- * @val: NN value or SP value/preference list
- * @len: length of @val in bytes
- * @server: whether this node is the server (1) or the client (0)
- */
-static u8 dccp_feat_change_recv(struct list_head *fn, u8 is_mandatory, u8 opt,
- u8 feat, u8 *val, u8 len, const bool server)
-{
- u8 defval, type = dccp_feat_type(feat);
- const bool local = (opt == DCCPO_CHANGE_R);
- struct dccp_feat_entry *entry;
- dccp_feat_val fval;
-
- if (len == 0 || type == FEAT_UNKNOWN) /* 6.1 and 6.6.8 */
- goto unknown_feature_or_value;
-
- dccp_feat_print_opt(opt, feat, val, len, is_mandatory);
-
- /*
- * Negotiation of NN features: Change R is invalid, so there is no
- * simultaneous negotiation; hence we do not look up in the list.
- */
- if (type == FEAT_NN) {
- if (local || len > sizeof(fval.nn))
- goto unknown_feature_or_value;
-
- /* 6.3.2: "The feature remote MUST accept any valid value..." */
- fval.nn = dccp_decode_value_var(val, len);
- if (!dccp_feat_is_valid_nn_val(feat, fval.nn))
- goto unknown_feature_or_value;
+ /* XXX check the return value of dccp_feat_update */
+ break;
+ }
- return dccp_feat_push_confirm(fn, feat, local, &fval);
+ if (!opt->dccpop_conf)
+ all_confirmed = 0;
}
- /*
- * Unidirectional/simultaneous negotiation of SP features (6.3.1)
+ /* fix re-transmit timer */
+ /* XXX gotta make sure that no option negotiation occurs during
+ * connection shutdown. Consider that the CLOSEREQ is sent and timer is
+ * on. if all options are confirmed it might kill timer which should
+ * remain alive until close is received.
*/
- entry = dccp_feat_list_lookup(fn, feat, local);
- if (entry == NULL) {
- /*
- * No particular preferences have been registered. We deal with
- * this situation by assuming that all valid values are equally
- * acceptable, and apply the following checks:
- * - if the peer's list is a singleton, we accept a valid value;
- * - if we are the server, we first try to see if the peer (the
- * client) advertises the default value. If yes, we use it,
- * otherwise we accept the preferred value;
- * - else if we are the client, we use the first list element.
- */
- if (dccp_feat_clone_sp_val(&fval, val, 1))
- return DCCP_RESET_CODE_TOO_BUSY;
-
- if (len > 1 && server) {
- defval = dccp_feat_default_value(feat);
- if (dccp_feat_preflist_match(&defval, 1, val, len) > -1)
- fval.sp.vec[0] = defval;
- } else if (!dccp_feat_is_valid_sp_val(feat, fval.sp.vec[0])) {
- kfree(fval.sp.vec);
- goto unknown_feature_or_value;
- }
-
- /* Treat unsupported CCIDs like invalid values */
- if (feat == DCCPF_CCID && !ccid_support_check(fval.sp.vec, 1)) {
- kfree(fval.sp.vec);
- goto not_valid_or_not_known;
- }
-
- return dccp_feat_push_confirm(fn, feat, local, &fval);
-
- } else if (entry->state == FEAT_UNSTABLE) { /* 6.6.2 */
- return 0;
+ if (all_confirmed) {
+ dccp_pr_debug("clear feat negotiation timer %p\n", sk);
+ inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS);
}
- if (dccp_feat_reconcile(&entry->val, val, len, server, true)) {
- entry->empty_confirm = 0;
- } else if (is_mandatory) {
- return DCCP_RESET_CODE_MANDATORY_ERROR;
- } else if (entry->state == FEAT_INITIALISING) {
- /*
- * Failed simultaneous negotiation (server only): try to `save'
- * the connection by checking whether entry contains the default
- * value for @feat. If yes, send an empty Confirm to signal that
- * the received Change was not understood - which implies using
- * the default value.
- * If this also fails, we use Reset as the last resort.
- */
- WARN_ON(!server);
- defval = dccp_feat_default_value(feat);
- if (!dccp_feat_reconcile(&entry->val, &defval, 1, server, true))
- return DCCP_RESET_CODE_OPTION_ERROR;
- entry->empty_confirm = 1;
- }
- entry->needs_confirm = 1;
- entry->needs_mandatory = 0;
- entry->state = FEAT_STABLE;
+ if (!found)
+ dccp_pr_debug("%s(%d, ...) never requested\n",
+ dccp_feat_typename(type), feature);
return 0;
-
-unknown_feature_or_value:
- if (!is_mandatory)
- return dccp_push_empty_confirm(fn, feat, local);
-
-not_valid_or_not_known:
- return is_mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR
- : DCCP_RESET_CODE_OPTION_ERROR;
}
-/**
- * dccp_feat_confirm_recv - Process received Confirm options
- * @fn: feature-negotiation list to update
- * @is_mandatory: whether @opt was preceded by a Mandatory option
- * @opt: %DCCPO_CONFIRM_L or %DCCPO_CONFIRM_R
- * @feat: one of %dccp_feature_numbers
- * @val: NN value or SP value/preference list
- * @len: length of @val in bytes
- * @server: whether this node is server (1) or client (0)
- */
-static u8 dccp_feat_confirm_recv(struct list_head *fn, u8 is_mandatory, u8 opt,
- u8 feat, u8 *val, u8 len, const bool server)
-{
- u8 *plist, plen, type = dccp_feat_type(feat);
- const bool local = (opt == DCCPO_CONFIRM_R);
- struct dccp_feat_entry *entry = dccp_feat_list_lookup(fn, feat, local);
-
- dccp_feat_print_opt(opt, feat, val, len, is_mandatory);
-
- if (entry == NULL) { /* nothing queued: ignore or handle error */
- if (is_mandatory && type == FEAT_UNKNOWN)
- return DCCP_RESET_CODE_MANDATORY_ERROR;
-
- if (!local && type == FEAT_NN) /* 6.3.2 */
- goto confirmation_failed;
- return 0;
- }
-
- if (entry->state != FEAT_CHANGING) /* 6.6.2 */
- return 0;
-
- if (len == 0) {
- if (dccp_feat_must_be_understood(feat)) /* 6.6.7 */
- goto confirmation_failed;
- /*
- * Empty Confirm during connection setup: this means reverting
- * to the `old' value, which in this case is the default. Since
- * we handle default values automatically when no other values
- * have been set, we revert to the old value by removing this
- * entry from the list.
- */
- dccp_feat_list_pop(entry);
- return 0;
- }
+EXPORT_SYMBOL_GPL(dccp_feat_confirm_recv);
- if (type == FEAT_NN) {
- if (len > sizeof(entry->val.nn))
- goto confirmation_failed;
+void dccp_feat_clean(struct dccp_minisock *dmsk)
+{
+ struct dccp_opt_pend *opt, *next;
- if (entry->val.nn == dccp_decode_value_var(val, len))
- goto confirmation_succeeded;
+ list_for_each_entry_safe(opt, next, &dmsk->dccpms_pending,
+ dccpop_node) {
+ BUG_ON(opt->dccpop_val == NULL);
+ kfree(opt->dccpop_val);
- DCCP_WARN("Bogus Confirm for non-existing value\n");
- goto confirmation_failed;
- }
+ if (opt->dccpop_sc != NULL) {
+ BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
+ kfree(opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc);
+ }
- /*
- * Parsing SP Confirms: the first element of @val is the preferred
- * SP value which the peer confirms, the remainder depends on @len.
- * Note that only the confirmed value need to be a valid SP value.
- */
- if (!dccp_feat_is_valid_sp_val(feat, *val))
- goto confirmation_failed;
-
- if (len == 1) { /* peer didn't supply a preference list */
- plist = val;
- plen = len;
- } else { /* preferred value + preference list */
- plist = val + 1;
- plen = len - 1;
+ kfree(opt);
}
+ INIT_LIST_HEAD(&dmsk->dccpms_pending);
- /* Check whether the peer got the reconciliation right (6.6.8) */
- if (dccp_feat_reconcile(&entry->val, plist, plen, server, 0) != *val) {
- DCCP_WARN("Confirm selected the wrong value %u\n", *val);
- return DCCP_RESET_CODE_OPTION_ERROR;
+ list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) {
+ BUG_ON(opt == NULL);
+ if (opt->dccpop_val != NULL)
+ kfree(opt->dccpop_val);
+ kfree(opt);
}
- entry->val.sp.vec[0] = *val;
-
-confirmation_succeeded:
- entry->state = FEAT_STABLE;
- return 0;
-
-confirmation_failed:
- DCCP_WARN("Confirmation failed\n");
- return is_mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR
- : DCCP_RESET_CODE_OPTION_ERROR;
+ INIT_LIST_HEAD(&dmsk->dccpms_conf);
}
-/**
- * dccp_feat_handle_nn_established - Fast-path reception of NN options
- * @sk: socket of an established DCCP connection
- * @mandatory: whether @opt was preceded by a Mandatory option
- * @opt: %DCCPO_CHANGE_L | %DCCPO_CONFIRM_R (NN only)
- * @feat: NN number, one of %dccp_feature_numbers
- * @val: NN value
- * @len: length of @val in bytes
- * This function combines the functionality of change_recv/confirm_recv, with
- * the following differences (reset codes are the same):
- * - cleanup after receiving the Confirm;
- * - values are directly activated after successful parsing;
- * - deliberately restricted to NN features.
- * The restriction to NN features is essential since SP features can have non-
- * predictable outcomes (depending on the remote configuration), and are inter-
- * dependent (CCIDs for instance cause further dependencies).
+EXPORT_SYMBOL_GPL(dccp_feat_clean);
+
+/* this is to be called only when a listening sock creates its child. It is
+ * assumed by the function---the confirm is not duplicated, but rather it is
+ * "passed on".
*/
-static u8 dccp_feat_handle_nn_established(struct sock *sk, u8 mandatory, u8 opt,
- u8 feat, u8 *val, u8 len)
+int dccp_feat_clone(struct sock *oldsk, struct sock *newsk)
{
- struct list_head *fn = &dccp_sk(sk)->dccps_featneg;
- const bool local = (opt == DCCPO_CONFIRM_R);
- struct dccp_feat_entry *entry;
- u8 type = dccp_feat_type(feat);
- dccp_feat_val fval;
+ struct dccp_minisock *olddmsk = dccp_msk(oldsk);
+ struct dccp_minisock *newdmsk = dccp_msk(newsk);
+ struct dccp_opt_pend *opt;
+ int rc = 0;
- dccp_feat_print_opt(opt, feat, val, len, mandatory);
+ INIT_LIST_HEAD(&newdmsk->dccpms_pending);
+ INIT_LIST_HEAD(&newdmsk->dccpms_conf);
- /* Ignore non-mandatory unknown and non-NN features */
- if (type == FEAT_UNKNOWN) {
- if (local && !mandatory)
- return 0;
- goto fast_path_unknown;
- } else if (type != FEAT_NN) {
- return 0;
- }
-
- /*
- * We don't accept empty Confirms, since in fast-path feature
- * negotiation the values are enabled immediately after sending
- * the Change option.
- * Empty Changes on the other hand are invalid (RFC 4340, 6.1).
- */
- if (len == 0 || len > sizeof(fval.nn))
- goto fast_path_unknown;
-
- if (opt == DCCPO_CHANGE_L) {
- fval.nn = dccp_decode_value_var(val, len);
- if (!dccp_feat_is_valid_nn_val(feat, fval.nn))
- goto fast_path_unknown;
+ list_for_each_entry(opt, &olddmsk->dccpms_pending, dccpop_node) {
+ struct dccp_opt_pend *newopt;
+ /* copy the value of the option */
+ u8 *val = kmemdup(opt->dccpop_val, opt->dccpop_len, GFP_ATOMIC);
- if (dccp_feat_push_confirm(fn, feat, local, &fval) ||
- dccp_feat_activate(sk, feat, local, &fval))
- return DCCP_RESET_CODE_TOO_BUSY;
+ if (val == NULL)
+ goto out_clean;
- /* set the `Ack Pending' flag to piggyback a Confirm */
- inet_csk_schedule_ack(sk);
-
- } else if (opt == DCCPO_CONFIRM_R) {
- entry = dccp_feat_list_lookup(fn, feat, local);
- if (entry == NULL || entry->state != FEAT_CHANGING)
- return 0;
-
- fval.nn = dccp_decode_value_var(val, len);
- if (fval.nn != entry->val.nn) {
- DCCP_WARN("Bogus Confirm for non-existing value\n");
- goto fast_path_failed;
+ newopt = kmemdup(opt, sizeof(*newopt), GFP_ATOMIC);
+ if (newopt == NULL) {
+ kfree(val);
+ goto out_clean;
}
- /* It has been confirmed - so remove the entry */
- dccp_feat_list_pop(entry);
+ /* insert the option */
+ newopt->dccpop_val = val;
+ list_add_tail(&newopt->dccpop_node, &newdmsk->dccpms_pending);
- } else {
- DCCP_WARN("Received illegal option %u\n", opt);
- goto fast_path_failed;
+ /* XXX what happens with backlogs and multiple connections at
+ * once...
+ */
+ /* the master socket no longer needs to worry about confirms */
+ opt->dccpop_sc = NULL; /* it's not a memleak---new socket has it */
+
+ /* reset state for a new socket */
+ opt->dccpop_conf = 0;
}
- return 0;
-fast_path_unknown:
- if (!mandatory)
- return dccp_push_empty_confirm(fn, feat, local);
+ /* XXX not doing anything about the conf queue */
+
+out:
+ return rc;
-fast_path_failed:
- return mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR
- : DCCP_RESET_CODE_OPTION_ERROR;
+out_clean:
+ dccp_feat_clean(newdmsk);
+ rc = -ENOMEM;
+ goto out;
}
-/**
- * dccp_feat_parse_options - Process Feature-Negotiation Options
- * @sk: for general use and used by the client during connection setup
- * @dreq: used by the server during connection setup
- * @mandatory: whether @opt was preceded by a Mandatory option
- * @opt: %DCCPO_CHANGE_L | %DCCPO_CHANGE_R | %DCCPO_CONFIRM_L | %DCCPO_CONFIRM_R
- * @feat: one of %dccp_feature_numbers
- * @val: value contents of @opt
- * @len: length of @val in bytes
- * Returns 0 on success, a Reset code for ending the connection otherwise.
- */
-int dccp_feat_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
- u8 mandatory, u8 opt, u8 feat, u8 *val, u8 len)
+EXPORT_SYMBOL_GPL(dccp_feat_clone);
+
+static int __dccp_feat_init(struct dccp_minisock *dmsk, u8 type, u8 feat,
+ u8 *val, u8 len)
{
- struct dccp_sock *dp = dccp_sk(sk);
- struct list_head *fn = dreq ? &dreq->dreq_featneg : &dp->dccps_featneg;
- bool server = false;
+ int rc = -ENOMEM;
+ u8 *copy = kmemdup(val, len, GFP_KERNEL);
- switch (sk->sk_state) {
- /*
- * Negotiation during connection setup
- */
- case DCCP_LISTEN:
- server = true; /* fall through */
- case DCCP_REQUESTING:
- switch (opt) {
- case DCCPO_CHANGE_L:
- case DCCPO_CHANGE_R:
- return dccp_feat_change_recv(fn, mandatory, opt, feat,
- val, len, server);
- case DCCPO_CONFIRM_R:
- case DCCPO_CONFIRM_L:
- return dccp_feat_confirm_recv(fn, mandatory, opt, feat,
- val, len, server);
- }
- break;
- /*
- * Support for exchanging NN options on an established connection
- * This is currently restricted to Ack Ratio (RFC 4341, 6.1.2)
- */
- case DCCP_OPEN:
- case DCCP_PARTOPEN:
- return dccp_feat_handle_nn_established(sk, mandatory, opt, feat,
- val, len);
+ if (copy != NULL) {
+ rc = dccp_feat_change(dmsk, type, feat, copy, len, GFP_KERNEL);
+ if (rc)
+ kfree(copy);
}
- return 0; /* ignore FN options in all other states */
+ return rc;
}
-/**
- * dccp_feat_init - Seed feature negotiation with host-specific defaults
- * This initialises global defaults, depending on the value of the sysctls.
- * These can later be overridden by registering changes via setsockopt calls.
- * The last link in the chain is finalise_settings, to make sure that between
- * here and the start of actual feature negotiation no inconsistencies enter.
- *
- * All features not appearing below use either defaults or are otherwise
- * later adjusted through dccp_feat_finalise_settings().
- */
-int dccp_feat_init(struct sock *sk)
+int dccp_feat_init(struct dccp_minisock *dmsk)
{
- struct list_head *fn = &dccp_sk(sk)->dccps_featneg;
- u8 on = 1, off = 0;
int rc;
- struct {
- u8 *val;
- u8 len;
- } tx, rx;
-
- /* Non-negotiable (NN) features */
- rc = __feat_register_nn(fn, DCCPF_SEQUENCE_WINDOW, 0,
- sysctl_dccp_sequence_window);
- if (rc)
- return rc;
- /* Server-priority (SP) features */
-
- /* Advertise that short seqnos are not supported (7.6.1) */
- rc = __feat_register_sp(fn, DCCPF_SHORT_SEQNOS, true, true, &off, 1);
- if (rc)
- return rc;
+ INIT_LIST_HEAD(&dmsk->dccpms_pending);
+ INIT_LIST_HEAD(&dmsk->dccpms_conf);
- /* RFC 4340 12.1: "If a DCCP is not ECN capable, ..." */
- rc = __feat_register_sp(fn, DCCPF_ECN_INCAPABLE, true, true, &on, 1);
+ /* CCID L */
+ rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_CCID,
+ &dmsk->dccpms_tx_ccid, 1);
if (rc)
- return rc;
-
- /*
- * We advertise the available list of CCIDs and reorder according to
- * preferences, to avoid failure resulting from negotiating different
- * singleton values (which always leads to failure).
- * These settings can still (later) be overridden via sockopts.
- */
- if (ccid_get_builtin_ccids(&tx.val, &tx.len) ||
- ccid_get_builtin_ccids(&rx.val, &rx.len))
- return -ENOBUFS;
-
- /* Pre-load all CCID modules that are going to be advertised */
- rc = -EUNATCH;
- if (ccid_request_modules(tx.val, tx.len))
- goto free_ccid_lists;
-
- if (!dccp_feat_prefer(sysctl_dccp_tx_ccid, tx.val, tx.len) ||
- !dccp_feat_prefer(sysctl_dccp_rx_ccid, rx.val, rx.len))
- goto free_ccid_lists;
+ goto out;
- rc = __feat_register_sp(fn, DCCPF_CCID, true, false, tx.val, tx.len);
+ /* CCID R */
+ rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_R, DCCPF_CCID,
+ &dmsk->dccpms_rx_ccid, 1);
if (rc)
- goto free_ccid_lists;
+ goto out;
- rc = __feat_register_sp(fn, DCCPF_CCID, false, false, rx.val, rx.len);
-
-free_ccid_lists:
- kfree(tx.val);
- kfree(rx.val);
+ /* Ack ratio */
+ rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_ACK_RATIO,
+ &dmsk->dccpms_ack_ratio, 1);
+out:
return rc;
}
-int dccp_feat_activate_values(struct sock *sk, struct list_head *fn_list)
-{
- struct dccp_sock *dp = dccp_sk(sk);
- struct dccp_feat_entry *cur, *next;
- int idx;
- dccp_feat_val *fvals[DCCP_FEAT_SUPPORTED_MAX][2] = {
- [0 ... DCCP_FEAT_SUPPORTED_MAX-1] = { NULL, NULL }
- };
-
- list_for_each_entry(cur, fn_list, node) {
- /*
- * An empty Confirm means that either an unknown feature type
- * or an invalid value was present. In the first case there is
- * nothing to activate, in the other the default value is used.
- */
- if (cur->empty_confirm)
- continue;
+EXPORT_SYMBOL_GPL(dccp_feat_init);
- idx = dccp_feat_index(cur->feat_num);
- if (idx < 0) {
- DCCP_BUG("Unknown feature %u", cur->feat_num);
- goto activation_failed;
- }
- if (cur->state != FEAT_STABLE) {
- DCCP_CRIT("Negotiation of %s %s failed in state %s",
- cur->is_local ? "local" : "remote",
- dccp_feat_fname(cur->feat_num),
- dccp_feat_sname[cur->state]);
- goto activation_failed;
- }
- fvals[idx][cur->is_local] = &cur->val;
+#ifdef CONFIG_IP_DCCP_DEBUG
+const char *dccp_feat_typename(const u8 type)
+{
+ switch(type) {
+ case DCCPO_CHANGE_L: return("ChangeL");
+ case DCCPO_CONFIRM_L: return("ConfirmL");
+ case DCCPO_CHANGE_R: return("ChangeR");
+ case DCCPO_CONFIRM_R: return("ConfirmR");
+ /* the following case must not appear in feature negotation */
+ default: dccp_pr_debug("unknown type %d [BUG!]\n", type);
}
+ return NULL;
+}
- /*
- * Activate in decreasing order of index, so that the CCIDs are always
- * activated as the last feature. This avoids the case where a CCID
- * relies on the initialisation of one or more features that it depends
- * on (e.g. Send NDP Count, Send Ack Vector, and Ack Ratio features).
- */
- for (idx = DCCP_FEAT_SUPPORTED_MAX; --idx >= 0;)
- if (__dccp_feat_activate(sk, idx, 0, fvals[idx][0]) ||
- __dccp_feat_activate(sk, idx, 1, fvals[idx][1])) {
- DCCP_CRIT("Could not activate %d", idx);
- goto activation_failed;
- }
+EXPORT_SYMBOL_GPL(dccp_feat_typename);
- /* Clean up Change options which have been confirmed already */
- list_for_each_entry_safe(cur, next, fn_list, node)
- if (!cur->needs_confirm)
- dccp_feat_list_pop(cur);
+const char *dccp_feat_name(const u8 feat)
+{
+ static const char *feature_names[] = {
+ [DCCPF_RESERVED] = "Reserved",
+ [DCCPF_CCID] = "CCID",
+ [DCCPF_SHORT_SEQNOS] = "Allow Short Seqnos",
+ [DCCPF_SEQUENCE_WINDOW] = "Sequence Window",
+ [DCCPF_ECN_INCAPABLE] = "ECN Incapable",
+ [DCCPF_ACK_RATIO] = "Ack Ratio",
+ [DCCPF_SEND_ACK_VECTOR] = "Send ACK Vector",
+ [DCCPF_SEND_NDP_COUNT] = "Send NDP Count",
+ [DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage",
+ [DCCPF_DATA_CHECKSUM] = "Send Data Checksum",
+ };
+ if (feat > DCCPF_DATA_CHECKSUM && feat < DCCPF_MIN_CCID_SPECIFIC)
+ return feature_names[DCCPF_RESERVED];
- dccp_pr_debug("Activation OK\n");
- return 0;
+ if (feat >= DCCPF_MIN_CCID_SPECIFIC)
+ return "CCID-specific";
-activation_failed:
- /*
- * We clean up everything that may have been allocated, since
- * it is difficult to track at which stage negotiation failed.
- * This is ok, since all allocation functions below are robust
- * against NULL arguments.
- */
- ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
- ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
- dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
- dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
- dp->dccps_hc_rx_ackvec = NULL;
- return -1;
+ return feature_names[feat];
}
+
+EXPORT_SYMBOL_GPL(dccp_feat_name);
+#endif /* CONFIG_IP_DCCP_DEBUG */
projects / linux-2.6-omap-h63xx.git / blobdiff