diff options
-rw-r--r-- | net/dccp/dccp.h | 1 | ||||
-rw-r--r-- | net/dccp/feat.c | 37 | ||||
-rw-r--r-- | net/dccp/output.c | 13 |
3 files changed, 47 insertions, 4 deletions
diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h index 1881527bdcd..e656dafb5d9 100644 --- a/net/dccp/dccp.h +++ b/net/dccp/dccp.h @@ -443,6 +443,7 @@ static inline int dccp_ack_pending(const struct sock *sk) } extern int dccp_feat_finalise_settings(struct dccp_sock *dp); +extern int dccp_feat_server_ccid_dependencies(struct dccp_request_sock *dreq); extern void dccp_feat_list_purge(struct list_head *fn_list); extern int dccp_insert_options(struct sock *sk, struct sk_buff *skb); diff --git a/net/dccp/feat.c b/net/dccp/feat.c index 4c414414732..4f86a48723f 100644 --- a/net/dccp/feat.c +++ b/net/dccp/feat.c @@ -166,6 +166,18 @@ static void dccp_feat_entry_destructor(struct dccp_feat_entry *entry) * - 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) @@ -560,6 +572,31 @@ int dccp_feat_finalise_settings(struct dccp_sock *dp) 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; + + 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; +} + static int dccp_feat_update_ccid(struct sock *sk, u8 type, u8 new_ccid_nr) { struct dccp_sock *dp = dccp_sk(sk); diff --git a/net/dccp/output.c b/net/dccp/output.c index 92f3f6f2ef5..fea30cdc0be 100644 --- a/net/dccp/output.c +++ b/net/dccp/output.c @@ -339,10 +339,12 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE; DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss; - if (dccp_insert_options_rsk(dreq, skb)) { - kfree_skb(skb); - return NULL; - } + /* Resolve feature dependencies resulting from choice of CCID */ + if (dccp_feat_server_ccid_dependencies(dreq)) + goto response_failed; + + if (dccp_insert_options_rsk(dreq, skb)) + goto response_failed; /* Build and checksum header */ dh = dccp_zeroed_hdr(skb, dccp_header_size); @@ -363,6 +365,9 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, inet_rsk(req)->acked = 1; DCCP_INC_STATS(DCCP_MIB_OUTSEGS); return skb; +response_failed: + kfree_skb(skb); + return NULL; } EXPORT_SYMBOL_GPL(dccp_make_response); |