static int dccp_feat_default_value(u8 feat_num)
{
int idx = dccp_feat_index(feat_num);
+ /*
+ * There are no default values for unknown features, so encountering a
+ * negative index here indicates a serious problem somewhere else.
+ */
+ DCCP_BUG_ON(idx < 0);
- return idx < 0 ? : dccp_feat_table[idx].default_value;
+ return idx < 0 ? 0 : dccp_feat_table[idx].default_value;
}
/* copy constructor, fval must not already contain allocated memory */
* - 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;
-
- 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;
-}
/**
* dccp_feat_entry_new - Central list update routine (called by all others)
return 0;
}
-/**
- * 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);
-
- if (new == NULL)
- return DCCP_RESET_CODE_TOO_BUSY;
-
- 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;
-
- return 0;
-}
-
-static int dccp_push_empty_confirm(struct list_head *fn_list, u8 feat, u8 local)
-{
- return dccp_feat_push_confirm(fn_list, feat, local, NULL);
-}
-
static inline void dccp_feat_list_pop(struct dccp_feat_entry *entry)
{
list_del(&entry->node);
!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;
return dccp_feat_push_change(fn, feat, is_local, mandatory, &fval);
}
-/**
- * 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(struct dccp_minisock *dmsk, u8 type, u8 feature,
+ u8 *val, u8 len, gfp_t gfp)
{
- /* any changes must be registered before establishing the connection */
- if (sk->sk_state != DCCP_CLOSED)
- return -EISCONN;
- if (dccp_feat_type(feat) != FEAT_NN)
+ struct dccp_opt_pend *opt;
+
+ dccp_feat_debug(type, feature, *val);
+
+ if (len > 3) {
+ DCCP_WARN("invalid length %d\n", len);
return -EINVAL;
- return __feat_register_nn(&dccp_sk(sk)->dccps_featneg, feat, 0, val);
-}
+ }
+ /* XXX add further sanity checks */
-/*
- * 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.
- */
- { /* 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 }
+ /* 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;
}
- };
- switch (ccid) {
- case DCCPC_CCID2:
- return ccid2_dependencies[is_local];
- case DCCPC_CCID3:
- return ccid3_dependencies[is_local];
- default:
- return NULL;
}
-}
-
-/**
- * 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 };
-
- /*
- * 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;
- return 0;
-}
-
-/**
- * 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;
+ /* negotiation for a new feature */
+ opt = kmalloc(sizeof(*opt), gfp);
+ if (opt == NULL)
+ return -ENOMEM;
- for (is_local = 0; is_local <= 1; is_local++) {
- entry = dccp_feat_list_lookup(fn, DCCPF_CCID, is_local);
+ opt->dccpop_type = type;
+ opt->dccpop_feat = feature;
+ opt->dccpop_len = len;
+ opt->dccpop_val = val;
+ opt->dccpop_conf = 0;
+ opt->dccpop_sc = NULL;
- if (entry != NULL && !entry->empty_confirm)
- ccid = entry->val.sp.vec[0];
- else
- ccid = dccp_feat_default_value(DCCPF_CCID);
+ BUG_ON(opt->dccpop_val == NULL);
- if (dccp_feat_propagate_ccid(fn, ccid, is_local))
- return -1;
- }
+ list_add_tail(&opt->dccpop_node, &dmsk->dccpms_pending);
return 0;
}
+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);
/* Ack ratio */
rc = __feat_register_nn(&dp->dccps_featneg, DCCPF_ACK_RATIO, 0,
- dp->dccps_l_ack_ratio);
+ dmsk->dccpms_ack_ratio);
out:
return rc;
}
git://bbs.cooldavid.org / net-next-2.6.git / blobdiff