static struct request_sock *rst_reqsk_alloc(unsigned short family) { struct request_sock *req; if (family == AF_INET) req = reqsk_alloc(&tcp_request_sock_ops); else #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) req = reqsk_alloc(&tcp6_request_sock_ops); #else return ERR_PTR(-EINVAL); #endif #ifdef CONFIG_TCP_MD5SIG if (req) { if (family == AF_INET) tcp_rsk(req)->af_specific = &tcp_request_sock_ipv4_ops; else tcp_rsk(req)->af_specific = &tcp_request_sock_ipv6_ops; } #endif return req; }
int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) { struct inet_request_sock *ireq; struct dccp_sock dp; struct request_sock *req; struct dccp_request_sock *dreq; const __be32 saddr = skb->nh.iph->saddr; const __be32 daddr = skb->nh.iph->daddr; const __be32 service = dccp_hdr_request(skb)->dccph_req_service; struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY; /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */ if (((struct rtable *)skb->dst)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { reset_code = DCCP_RESET_CODE_NO_CONNECTION; goto drop; } if (dccp_bad_service_code(sk, service)) { reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; goto drop; } /* * TW buckets are converted to open requests without * limitations, they conserve resources and peer is * evidently real one. */ if (inet_csk_reqsk_queue_is_full(sk)) goto drop; /* * Accept backlog is full. If we have already queued enough * of warm entries in syn queue, drop request. It is better than * clogging syn queue with openreqs with exponentially increasing * timeout. */ if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) goto drop; req = reqsk_alloc(sk->sk_prot->rsk_prot); if (req == NULL) goto drop; if (dccp_parse_options(sk, skb)) goto drop_and_free; dccp_openreq_init(req, &dp, skb); ireq = inet_rsk(req); ireq->loc_addr = daddr; ireq->rmt_addr = saddr; req->rcv_wnd = dccp_feat_default_sequence_window; ireq->opt = NULL; /* * Step 3: Process LISTEN state * * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie * * In fact we defer setting S.GSR, S.SWL, S.SWH to * dccp_create_openreq_child. */ dreq = dccp_rsk(req); dreq->dreq_isr = dcb->dccpd_seq; dreq->dreq_iss = dccp_v4_init_sequence(sk, skb); dreq->dreq_service = service; if (dccp_v4_send_response(sk, req, NULL)) goto drop_and_free; inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); return 0; drop_and_free: reqsk_free(req); drop: DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); dcb->dccpd_reset_code = reset_code; return -1; }