diff options
Diffstat (limited to 'net/dccp/minisocks.c')
| -rw-r--r-- | net/dccp/minisocks.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c new file mode 100644 index 00000000000..810f0c293b8 --- /dev/null +++ b/net/dccp/minisocks.c @@ -0,0 +1,199 @@ +/* + * net/dccp/minisocks.c + * + * An implementation of the DCCP protocol + * Arnaldo Carvalho de Melo <acme@conectiva.com.br> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/config.h> +#include <linux/dccp.h> +#include <linux/skbuff.h> +#include <linux/timer.h> + +#include <net/sock.h> +#include <net/xfrm.h> +#include <net/inet_timewait_sock.h> + +#include "ccid.h" +#include "dccp.h" + +void dccp_time_wait(struct sock *sk, int state, int timeo) +{ + /* FIXME: Implement */ + dccp_pr_debug("Want to help? Start here\n"); + dccp_set_state(sk, state); +} + +/* This is for handling early-kills of TIME_WAIT sockets. */ +void dccp_tw_deschedule(struct inet_timewait_sock *tw) +{ + dccp_pr_debug("Want to help? Start here\n"); + __inet_twsk_kill(tw, &dccp_hashinfo); +} + +struct sock *dccp_create_openreq_child(struct sock *sk, + const struct request_sock *req, + const struct sk_buff *skb) +{ + /* + * Step 3: Process LISTEN state + * + * // Generate a new socket and switch to that socket + * Set S := new socket for this port pair + */ + struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC); + + if (newsk != NULL) { + const struct dccp_request_sock *dreq = dccp_rsk(req); + struct inet_connection_sock *newicsk = inet_csk(sk); + struct dccp_sock *newdp = dccp_sk(newsk); + + newdp->dccps_hc_rx_ackpkts = NULL; + newdp->dccps_role = DCCP_ROLE_SERVER; + newicsk->icsk_rto = TCP_TIMEOUT_INIT; + + if (newdp->dccps_options.dccpo_send_ack_vector) { + newdp->dccps_hc_rx_ackpkts = dccp_ackpkts_alloc(DCCP_MAX_ACK_VECTOR_LEN, + GFP_ATOMIC); + /* + * XXX: We're using the same CCIDs set on the parent, i.e. sk_clone + * copied the master sock and left the CCID pointers for this child, + * that is why we do the __ccid_get calls. + */ + if (unlikely(newdp->dccps_hc_rx_ackpkts == NULL)) + goto out_free; + } + + if (unlikely(ccid_hc_rx_init(newdp->dccps_hc_rx_ccid, newsk) != 0 || + ccid_hc_tx_init(newdp->dccps_hc_tx_ccid, newsk) != 0)) { + dccp_ackpkts_free(newdp->dccps_hc_rx_ackpkts); + ccid_hc_rx_exit(newdp->dccps_hc_rx_ccid, newsk); + ccid_hc_tx_exit(newdp->dccps_hc_tx_ccid, newsk); +out_free: + /* It is still raw copy of parent, so invalidate + * destructor and make plain sk_free() */ + newsk->sk_destruct = NULL; + sk_free(newsk); + return NULL; + } + + __ccid_get(newdp->dccps_hc_rx_ccid); + __ccid_get(newdp->dccps_hc_tx_ccid); + + /* + * Step 3: Process LISTEN state + * + * Choose S.ISS (initial seqno) or set from Init Cookie + * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie + */ + + /* See dccp_v4_conn_request */ + newdp->dccps_options.dccpo_sequence_window = req->rcv_wnd; + + newdp->dccps_gar = newdp->dccps_isr = dreq->dreq_isr; + dccp_update_gsr(newsk, dreq->dreq_isr); + + newdp->dccps_iss = dreq->dreq_iss; + dccp_update_gss(newsk, dreq->dreq_iss); + + dccp_init_xmit_timers(newsk); + + DCCP_INC_STATS_BH(DCCP_MIB_PASSIVEOPENS); + } + return newsk; +} + +/* + * Process an incoming packet for RESPOND sockets represented + * as an request_sock. + */ +struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, + struct request_sock *req, + struct request_sock **prev) +{ + struct sock *child = NULL; + + /* Check for retransmitted REQUEST */ + if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) { + if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dccp_rsk(req)->dreq_isr)) { + struct dccp_request_sock *dreq = dccp_rsk(req); + + dccp_pr_debug("Retransmitted REQUEST\n"); + /* Send another RESPONSE packet */ + dccp_set_seqno(&dreq->dreq_iss, dreq->dreq_iss + 1); + dccp_set_seqno(&dreq->dreq_isr, DCCP_SKB_CB(skb)->dccpd_seq); + req->rsk_ops->rtx_syn_ack(sk, req, NULL); + } + /* Network Duplicate, discard packet */ + return NULL; + } + + DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR; + + if (dccp_hdr(skb)->dccph_type != DCCP_PKT_ACK && + dccp_hdr(skb)->dccph_type != DCCP_PKT_DATAACK) + goto drop; + + /* Invalid ACK */ + if (DCCP_SKB_CB(skb)->dccpd_ack_seq != dccp_rsk(req)->dreq_iss) { + dccp_pr_debug("Invalid ACK number: ack_seq=%llu, dreq_iss=%llu\n", + DCCP_SKB_CB(skb)->dccpd_ack_seq, dccp_rsk(req)->dreq_iss); + goto drop; + } + + child = dccp_v4_request_recv_sock(sk, skb, req, NULL); + if (child == NULL) + goto listen_overflow; + + /* FIXME: deal with options */ + + inet_csk_reqsk_queue_unlink(sk, req, prev); + inet_csk_reqsk_queue_removed(sk, req); + inet_csk_reqsk_queue_add(sk, req, child); +out: + return child; +listen_overflow: + dccp_pr_debug("listen_overflow!\n"); + DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; +drop: + if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET) + req->rsk_ops->send_reset(skb); + + inet_csk_reqsk_queue_drop(sk, req, prev); + goto out; +} + +/* + * Queue segment on the new socket if the new socket is active, + * otherwise we just shortcircuit this and continue with + * the new socket. + */ +int dccp_child_process(struct sock *parent, struct sock *child, + struct sk_buff *skb) +{ + int ret = 0; + const int state = child->sk_state; + + if (!sock_owned_by_user(child)) { + ret = dccp_rcv_state_process(child, skb, dccp_hdr(skb), skb->len); + + /* Wakeup parent, send SIGIO */ + if (state == DCCP_RESPOND && child->sk_state != state) + parent->sk_data_ready(parent, 0); + } else { + /* Alas, it is possible again, because we do lookup + * in main socket hash table and lock on listening + * socket does not protect us more. + */ + sk_add_backlog(child, skb); + } + + bh_unlock_sock(child); + sock_put(child); + return ret; +} |