forked from luck/tmp_suning_uos_patched
b6ee3d4ada
Introducing functions to add to or subtract from a timeval variable and renaming now_delta to timeval_new_delta that calls do_gettimeofday and then timeval_delta, that should be used when there are several deltas made relative to the current time or setting variables to it, so as to avoid calling do_gettimeofday excessively. I'm leaving these "timeval_" prefixed funcions internal to DCCP for a while till we're sure there are no subtle bugs in it. It also is more correct as it checks if the number of usecs added to or subtracted from a tv_usec field is more than 2 seconds. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
856 lines
23 KiB
C
856 lines
23 KiB
C
/*
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* net/dccp/options.c
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*
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* An implementation of the DCCP protocol
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* Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
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* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
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* Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/config.h>
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#include <linux/dccp.h>
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/skbuff.h>
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#include "ccid.h"
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#include "dccp.h"
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static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
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struct sock *sk,
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const u64 ackno,
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const unsigned char len,
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const unsigned char *vector);
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/* stores the default values for new connection. may be changed with sysctl */
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static const struct dccp_options dccpo_default_values = {
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.dccpo_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW,
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.dccpo_ccid = DCCPF_INITIAL_CCID,
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.dccpo_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR,
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.dccpo_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT,
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};
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void dccp_options_init(struct dccp_options *dccpo)
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{
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memcpy(dccpo, &dccpo_default_values, sizeof(*dccpo));
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}
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static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
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{
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u32 value = 0;
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if (len > 3)
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value += *bf++ << 24;
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if (len > 2)
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value += *bf++ << 16;
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if (len > 1)
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value += *bf++ << 8;
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if (len > 0)
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value += *bf;
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return value;
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}
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int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
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{
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struct dccp_sock *dp = dccp_sk(sk);
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#ifdef CONFIG_IP_DCCP_DEBUG
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const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
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"CLIENT rx opt: " : "server rx opt: ";
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#endif
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const struct dccp_hdr *dh = dccp_hdr(skb);
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const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
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unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
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unsigned char *opt_ptr = options;
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const unsigned char *opt_end = (unsigned char *)dh +
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(dh->dccph_doff * 4);
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struct dccp_options_received *opt_recv = &dp->dccps_options_received;
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unsigned char opt, len;
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unsigned char *value;
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memset(opt_recv, 0, sizeof(*opt_recv));
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while (opt_ptr != opt_end) {
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opt = *opt_ptr++;
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len = 0;
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value = NULL;
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/* Check if this isn't a single byte option */
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if (opt > DCCPO_MAX_RESERVED) {
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if (opt_ptr == opt_end)
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goto out_invalid_option;
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len = *opt_ptr++;
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if (len < 3)
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goto out_invalid_option;
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/*
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* Remove the type and len fields, leaving
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* just the value size
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*/
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len -= 2;
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value = opt_ptr;
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opt_ptr += len;
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if (opt_ptr > opt_end)
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goto out_invalid_option;
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}
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switch (opt) {
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case DCCPO_PADDING:
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break;
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case DCCPO_NDP_COUNT:
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if (len > 3)
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goto out_invalid_option;
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opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
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dccp_pr_debug("%sNDP count=%d\n", debug_prefix,
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opt_recv->dccpor_ndp);
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break;
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case DCCPO_ACK_VECTOR_0:
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if (len > DCCP_MAX_ACK_VECTOR_LEN)
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goto out_invalid_option;
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if (pkt_type == DCCP_PKT_DATA)
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continue;
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opt_recv->dccpor_ack_vector_len = len;
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opt_recv->dccpor_ack_vector_idx = value - options;
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dccp_pr_debug("%sACK vector 0, len=%d, ack_ackno=%llu\n",
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debug_prefix, len,
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(unsigned long long)
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DCCP_SKB_CB(skb)->dccpd_ack_seq);
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dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq,
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value, len);
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dccp_ackpkts_check_rcv_ackvector(dp->dccps_hc_rx_ackpkts,
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sk,
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DCCP_SKB_CB(skb)->dccpd_ack_seq,
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len, value);
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break;
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case DCCPO_TIMESTAMP:
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if (len != 4)
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goto out_invalid_option;
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opt_recv->dccpor_timestamp = ntohl(*(u32 *)value);
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dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp;
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do_gettimeofday(&dp->dccps_timestamp_time);
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dccp_pr_debug("%sTIMESTAMP=%u, ackno=%llu\n",
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debug_prefix, opt_recv->dccpor_timestamp,
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(unsigned long long)
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DCCP_SKB_CB(skb)->dccpd_ack_seq);
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break;
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case DCCPO_TIMESTAMP_ECHO:
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if (len != 4 && len != 6 && len != 8)
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goto out_invalid_option;
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opt_recv->dccpor_timestamp_echo = ntohl(*(u32 *)value);
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dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, ackno=%llu, ",
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debug_prefix,
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opt_recv->dccpor_timestamp_echo,
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len + 2,
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(unsigned long long)
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DCCP_SKB_CB(skb)->dccpd_ack_seq);
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if (len > 4) {
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if (len == 6)
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opt_recv->dccpor_elapsed_time =
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ntohs(*(u16 *)(value + 4));
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else
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opt_recv->dccpor_elapsed_time =
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ntohl(*(u32 *)(value + 4));
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dccp_pr_debug("%sTIMESTAMP_ECHO ELAPSED_TIME=%d\n",
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debug_prefix,
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opt_recv->dccpor_elapsed_time);
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}
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break;
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case DCCPO_ELAPSED_TIME:
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if (len != 2 && len != 4)
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goto out_invalid_option;
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if (pkt_type == DCCP_PKT_DATA)
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continue;
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if (len == 2)
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opt_recv->dccpor_elapsed_time =
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ntohs(*(u16 *)value);
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else
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opt_recv->dccpor_elapsed_time =
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ntohl(*(u32 *)value);
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dccp_pr_debug("%sELAPSED_TIME=%d\n", debug_prefix,
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opt_recv->dccpor_elapsed_time);
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break;
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/*
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* From draft-ietf-dccp-spec-11.txt:
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*
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* Option numbers 128 through 191 are for
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* options sent from the HC-Sender to the
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* HC-Receiver; option numbers 192 through 255
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* are for options sent from the HC-Receiver to
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* the HC-Sender.
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*/
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case 128 ... 191: {
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const u16 idx = value - options;
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if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk,
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opt, len, idx,
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value) != 0)
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goto out_invalid_option;
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}
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break;
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case 192 ... 255: {
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const u16 idx = value - options;
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if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
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opt, len, idx,
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value) != 0)
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goto out_invalid_option;
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}
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break;
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default:
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pr_info("DCCP(%p): option %d(len=%d) not "
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"implemented, ignoring\n",
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sk, opt, len);
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break;
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}
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}
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return 0;
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out_invalid_option:
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DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT);
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DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR;
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pr_info("DCCP(%p): invalid option %d, len=%d\n", sk, opt, len);
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return -1;
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}
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static void dccp_encode_value_var(const u32 value, unsigned char *to,
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const unsigned int len)
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{
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if (len > 3)
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*to++ = (value & 0xFF000000) >> 24;
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if (len > 2)
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*to++ = (value & 0xFF0000) >> 16;
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if (len > 1)
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*to++ = (value & 0xFF00) >> 8;
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if (len > 0)
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*to++ = (value & 0xFF);
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}
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static inline int dccp_ndp_len(const int ndp)
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{
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return likely(ndp <= 0xFF) ? 1 : ndp <= 0xFFFF ? 2 : 3;
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}
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void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
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const unsigned char option,
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const void *value, const unsigned char len)
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{
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unsigned char *to;
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if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) {
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LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert "
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"%d option!\n", option);
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return;
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}
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DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2;
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to = skb_push(skb, len + 2);
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*to++ = option;
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*to++ = len + 2;
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memcpy(to, value, len);
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}
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EXPORT_SYMBOL_GPL(dccp_insert_option);
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static void dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb)
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{
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struct dccp_sock *dp = dccp_sk(sk);
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int ndp = dp->dccps_ndp_count;
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if (dccp_non_data_packet(skb))
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++dp->dccps_ndp_count;
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else
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dp->dccps_ndp_count = 0;
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if (ndp > 0) {
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unsigned char *ptr;
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const int ndp_len = dccp_ndp_len(ndp);
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const int len = ndp_len + 2;
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if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
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return;
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DCCP_SKB_CB(skb)->dccpd_opt_len += len;
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ptr = skb_push(skb, len);
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*ptr++ = DCCPO_NDP_COUNT;
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*ptr++ = len;
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dccp_encode_value_var(ndp, ptr, ndp_len);
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}
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}
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static inline int dccp_elapsed_time_len(const u32 elapsed_time)
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{
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return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
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}
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void dccp_insert_option_elapsed_time(struct sock *sk,
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struct sk_buff *skb,
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u32 elapsed_time)
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{
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#ifdef CONFIG_IP_DCCP_DEBUG
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struct dccp_sock *dp = dccp_sk(sk);
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const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
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"CLIENT TX opt: " : "server TX opt: ";
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#endif
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const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
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const int len = 2 + elapsed_time_len;
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unsigned char *to;
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if (elapsed_time_len == 0)
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return;
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if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
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LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to "
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"insert elapsed time!\n");
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return;
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}
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DCCP_SKB_CB(skb)->dccpd_opt_len += len;
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to = skb_push(skb, len);
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*to++ = DCCPO_ELAPSED_TIME;
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*to++ = len;
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if (elapsed_time_len == 2) {
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const u16 var16 = htons((u16)elapsed_time);
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memcpy(to, &var16, 2);
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} else {
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const u32 var32 = htonl(elapsed_time);
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memcpy(to, &var32, 4);
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}
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dccp_pr_debug("%sELAPSED_TIME=%u, len=%d, seqno=%llu\n",
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debug_prefix, elapsed_time,
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len,
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(unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);
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}
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EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);
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static void dccp_insert_option_ack_vector(struct sock *sk, struct sk_buff *skb)
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{
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struct dccp_sock *dp = dccp_sk(sk);
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#ifdef CONFIG_IP_DCCP_DEBUG
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const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
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"CLIENT TX opt: " : "server TX opt: ";
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#endif
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struct dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
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int len = ap->dccpap_buf_vector_len + 2;
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const u32 elapsed_time = timeval_now_delta(&ap->dccpap_time) / 10;
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unsigned char *to, *from;
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if (elapsed_time != 0)
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dccp_insert_option_elapsed_time(sk, skb, elapsed_time);
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if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
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LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to "
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"insert ACK Vector!\n");
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return;
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}
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/*
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* XXX: now we have just one ack vector sent record, so
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* we have to wait for it to be cleared.
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*
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* Of course this is not acceptable, but this is just for
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* basic testing now.
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*/
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if (ap->dccpap_ack_seqno != DCCP_MAX_SEQNO + 1)
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return;
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DCCP_SKB_CB(skb)->dccpd_opt_len += len;
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to = skb_push(skb, len);
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*to++ = DCCPO_ACK_VECTOR_0;
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*to++ = len;
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len = ap->dccpap_buf_vector_len;
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from = ap->dccpap_buf + ap->dccpap_buf_head;
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/* Check if buf_head wraps */
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if (ap->dccpap_buf_head + len > ap->dccpap_buf_len) {
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const unsigned int tailsize = (ap->dccpap_buf_len -
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ap->dccpap_buf_head);
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memcpy(to, from, tailsize);
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to += tailsize;
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len -= tailsize;
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from = ap->dccpap_buf;
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}
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memcpy(to, from, len);
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/*
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* From draft-ietf-dccp-spec-11.txt:
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*
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* For each acknowledgement it sends, the HC-Receiver will add an
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* acknowledgement record. ack_seqno will equal the HC-Receiver
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* sequence number it used for the ack packet; ack_ptr will equal
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* buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
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* equal buf_nonce.
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*
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* This implemention uses just one ack record for now.
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*/
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ap->dccpap_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
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ap->dccpap_ack_ptr = ap->dccpap_buf_head;
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ap->dccpap_ack_ackno = ap->dccpap_buf_ackno;
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ap->dccpap_ack_nonce = ap->dccpap_buf_nonce;
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ap->dccpap_ack_vector_len = ap->dccpap_buf_vector_len;
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dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
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"ack_ackno=%llu\n",
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debug_prefix, ap->dccpap_ack_vector_len,
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(unsigned long long) ap->dccpap_ack_seqno,
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(unsigned long long) ap->dccpap_ack_ackno);
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}
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void dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
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{
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struct timeval tv;
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u32 now;
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do_gettimeofday(&tv);
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now = (tv.tv_sec * USEC_PER_SEC + tv.tv_usec) / 10;
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/* yes this will overflow but that is the point as we want a
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* 10 usec 32 bit timer which mean it wraps every 11.9 hours */
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now = htonl(now);
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dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now));
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}
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EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);
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static void dccp_insert_option_timestamp_echo(struct sock *sk,
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struct sk_buff *skb)
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{
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struct dccp_sock *dp = dccp_sk(sk);
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#ifdef CONFIG_IP_DCCP_DEBUG
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const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
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"CLIENT TX opt: " : "server TX opt: ";
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#endif
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u32 tstamp_echo;
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const u32 elapsed_time =
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timeval_now_delta(&dp->dccps_timestamp_time) / 10;
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const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
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const int len = 6 + elapsed_time_len;
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unsigned char *to;
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if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
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LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert "
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"timestamp echo!\n");
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return;
|
|
}
|
|
|
|
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
|
|
|
|
to = skb_push(skb, len);
|
|
*to++ = DCCPO_TIMESTAMP_ECHO;
|
|
*to++ = len;
|
|
|
|
tstamp_echo = htonl(dp->dccps_timestamp_echo);
|
|
memcpy(to, &tstamp_echo, 4);
|
|
to += 4;
|
|
|
|
if (elapsed_time_len == 2) {
|
|
const u16 var16 = htons((u16)elapsed_time);
|
|
memcpy(to, &var16, 2);
|
|
} else if (elapsed_time_len == 4) {
|
|
const u32 var32 = htonl(elapsed_time);
|
|
memcpy(to, &var32, 4);
|
|
}
|
|
|
|
dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, seqno=%llu\n",
|
|
debug_prefix, dp->dccps_timestamp_echo,
|
|
len,
|
|
(unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);
|
|
|
|
dp->dccps_timestamp_echo = 0;
|
|
dp->dccps_timestamp_time.tv_sec = 0;
|
|
dp->dccps_timestamp_time.tv_usec = 0;
|
|
}
|
|
|
|
void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct dccp_sock *dp = dccp_sk(sk);
|
|
|
|
DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
|
|
|
|
if (dp->dccps_options.dccpo_send_ndp_count)
|
|
dccp_insert_option_ndp(sk, skb);
|
|
|
|
if (!dccp_packet_without_ack(skb)) {
|
|
if (dp->dccps_options.dccpo_send_ack_vector &&
|
|
(dp->dccps_hc_rx_ackpkts->dccpap_buf_ackno !=
|
|
DCCP_MAX_SEQNO + 1))
|
|
dccp_insert_option_ack_vector(sk, skb);
|
|
|
|
if (dp->dccps_timestamp_echo != 0)
|
|
dccp_insert_option_timestamp_echo(sk, skb);
|
|
}
|
|
|
|
ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb);
|
|
ccid_hc_tx_insert_options(dp->dccps_hc_tx_ccid, sk, skb);
|
|
|
|
/* XXX: insert other options when appropriate */
|
|
|
|
if (DCCP_SKB_CB(skb)->dccpd_opt_len != 0) {
|
|
/* The length of all options has to be a multiple of 4 */
|
|
int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
|
|
|
|
if (padding != 0) {
|
|
padding = 4 - padding;
|
|
memset(skb_push(skb, padding), 0, padding);
|
|
DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
|
|
}
|
|
}
|
|
}
|
|
|
|
struct dccp_ackpkts *dccp_ackpkts_alloc(const unsigned int len,
|
|
const unsigned int __nocast priority)
|
|
{
|
|
struct dccp_ackpkts *ap = kmalloc(sizeof(*ap) + len, priority);
|
|
|
|
if (ap != NULL) {
|
|
#ifdef CONFIG_IP_DCCP_DEBUG
|
|
memset(ap->dccpap_buf, 0xFF, len);
|
|
#endif
|
|
ap->dccpap_buf_len = len;
|
|
ap->dccpap_buf_head =
|
|
ap->dccpap_buf_tail =
|
|
ap->dccpap_buf_len - 1;
|
|
ap->dccpap_buf_ackno =
|
|
ap->dccpap_ack_ackno =
|
|
ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
|
|
ap->dccpap_buf_nonce = ap->dccpap_buf_nonce = 0;
|
|
ap->dccpap_ack_ptr = 0;
|
|
ap->dccpap_time.tv_sec = 0;
|
|
ap->dccpap_time.tv_usec = 0;
|
|
ap->dccpap_buf_vector_len = ap->dccpap_ack_vector_len = 0;
|
|
}
|
|
|
|
return ap;
|
|
}
|
|
|
|
void dccp_ackpkts_free(struct dccp_ackpkts *ap)
|
|
{
|
|
if (ap != NULL) {
|
|
#ifdef CONFIG_IP_DCCP_DEBUG
|
|
memset(ap, 0xFF, sizeof(*ap) + ap->dccpap_buf_len);
|
|
#endif
|
|
kfree(ap);
|
|
}
|
|
}
|
|
|
|
static inline u8 dccp_ackpkts_state(const struct dccp_ackpkts *ap,
|
|
const unsigned int index)
|
|
{
|
|
return ap->dccpap_buf[index] & DCCP_ACKPKTS_STATE_MASK;
|
|
}
|
|
|
|
static inline u8 dccp_ackpkts_len(const struct dccp_ackpkts *ap,
|
|
const unsigned int index)
|
|
{
|
|
return ap->dccpap_buf[index] & DCCP_ACKPKTS_LEN_MASK;
|
|
}
|
|
|
|
/*
|
|
* If several packets are missing, the HC-Receiver may prefer to enter multiple
|
|
* bytes with run length 0, rather than a single byte with a larger run length;
|
|
* this simplifies table updates if one of the missing packets arrives.
|
|
*/
|
|
static inline int dccp_ackpkts_set_buf_head_state(struct dccp_ackpkts *ap,
|
|
const unsigned int packets,
|
|
const unsigned char state)
|
|
{
|
|
unsigned int gap;
|
|
signed long new_head;
|
|
|
|
if (ap->dccpap_buf_vector_len + packets > ap->dccpap_buf_len)
|
|
return -ENOBUFS;
|
|
|
|
gap = packets - 1;
|
|
new_head = ap->dccpap_buf_head - packets;
|
|
|
|
if (new_head < 0) {
|
|
if (gap > 0) {
|
|
memset(ap->dccpap_buf, DCCP_ACKPKTS_STATE_NOT_RECEIVED,
|
|
gap + new_head + 1);
|
|
gap = -new_head;
|
|
}
|
|
new_head += ap->dccpap_buf_len;
|
|
}
|
|
|
|
ap->dccpap_buf_head = new_head;
|
|
|
|
if (gap > 0)
|
|
memset(ap->dccpap_buf + ap->dccpap_buf_head + 1,
|
|
DCCP_ACKPKTS_STATE_NOT_RECEIVED, gap);
|
|
|
|
ap->dccpap_buf[ap->dccpap_buf_head] = state;
|
|
ap->dccpap_buf_vector_len += packets;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Implements the draft-ietf-dccp-spec-11.txt Appendix A
|
|
*/
|
|
int dccp_ackpkts_add(struct dccp_ackpkts *ap, u64 ackno, u8 state)
|
|
{
|
|
/*
|
|
* Check at the right places if the buffer is full, if it is, tell the
|
|
* caller to start dropping packets till the HC-Sender acks our ACK
|
|
* vectors, when we will free up space in dccpap_buf.
|
|
*
|
|
* We may well decide to do buffer compression, etc, but for now lets
|
|
* just drop.
|
|
*
|
|
* From Appendix A:
|
|
*
|
|
* Of course, the circular buffer may overflow, either when the
|
|
* HC-Sender is sending data at a very high rate, when the
|
|
* HC-Receiver's acknowledgements are not reaching the HC-Sender,
|
|
* or when the HC-Sender is forgetting to acknowledge those acks
|
|
* (so the HC-Receiver is unable to clean up old state). In this
|
|
* case, the HC-Receiver should either compress the buffer (by
|
|
* increasing run lengths when possible), transfer its state to
|
|
* a larger buffer, or, as a last resort, drop all received
|
|
* packets, without processing them whatsoever, until its buffer
|
|
* shrinks again.
|
|
*/
|
|
|
|
/* See if this is the first ackno being inserted */
|
|
if (ap->dccpap_buf_vector_len == 0) {
|
|
ap->dccpap_buf[ap->dccpap_buf_head] = state;
|
|
ap->dccpap_buf_vector_len = 1;
|
|
} else if (after48(ackno, ap->dccpap_buf_ackno)) {
|
|
const u64 delta = dccp_delta_seqno(ap->dccpap_buf_ackno,
|
|
ackno);
|
|
|
|
/*
|
|
* Look if the state of this packet is the same as the
|
|
* previous ackno and if so if we can bump the head len.
|
|
*/
|
|
if (delta == 1 &&
|
|
dccp_ackpkts_state(ap, ap->dccpap_buf_head) == state &&
|
|
(dccp_ackpkts_len(ap, ap->dccpap_buf_head) <
|
|
DCCP_ACKPKTS_LEN_MASK))
|
|
ap->dccpap_buf[ap->dccpap_buf_head]++;
|
|
else if (dccp_ackpkts_set_buf_head_state(ap, delta, state))
|
|
return -ENOBUFS;
|
|
} else {
|
|
/*
|
|
* A.1.2. Old Packets
|
|
*
|
|
* When a packet with Sequence Number S arrives, and
|
|
* S <= buf_ackno, the HC-Receiver will scan the table
|
|
* for the byte corresponding to S. (Indexing structures
|
|
* could reduce the complexity of this scan.)
|
|
*/
|
|
u64 delta = dccp_delta_seqno(ackno, ap->dccpap_buf_ackno);
|
|
unsigned int index = ap->dccpap_buf_head;
|
|
|
|
while (1) {
|
|
const u8 len = dccp_ackpkts_len(ap, index);
|
|
const u8 state = dccp_ackpkts_state(ap, index);
|
|
/*
|
|
* valid packets not yet in dccpap_buf have a reserved
|
|
* entry, with a len equal to 0.
|
|
*/
|
|
if (state == DCCP_ACKPKTS_STATE_NOT_RECEIVED &&
|
|
len == 0 && delta == 0) { /* Found our
|
|
reserved seat! */
|
|
dccp_pr_debug("Found %llu reserved seat!\n",
|
|
(unsigned long long) ackno);
|
|
ap->dccpap_buf[index] = state;
|
|
goto out;
|
|
}
|
|
/* len == 0 means one packet */
|
|
if (delta < len + 1)
|
|
goto out_duplicate;
|
|
|
|
delta -= len + 1;
|
|
if (++index == ap->dccpap_buf_len)
|
|
index = 0;
|
|
}
|
|
}
|
|
|
|
ap->dccpap_buf_ackno = ackno;
|
|
do_gettimeofday(&ap->dccpap_time);
|
|
out:
|
|
dccp_pr_debug("");
|
|
dccp_ackpkts_print(ap);
|
|
return 0;
|
|
|
|
out_duplicate:
|
|
/* Duplicate packet */
|
|
dccp_pr_debug("Received a dup or already considered lost "
|
|
"packet: %llu\n", (unsigned long long) ackno);
|
|
return -EILSEQ;
|
|
}
|
|
|
|
#ifdef CONFIG_IP_DCCP_DEBUG
|
|
void dccp_ackvector_print(const u64 ackno, const unsigned char *vector,
|
|
int len)
|
|
{
|
|
if (!dccp_debug)
|
|
return;
|
|
|
|
printk("ACK vector len=%d, ackno=%llu |", len,
|
|
(unsigned long long) ackno);
|
|
|
|
while (len--) {
|
|
const u8 state = (*vector & DCCP_ACKPKTS_STATE_MASK) >> 6;
|
|
const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
|
|
|
|
printk("%d,%d|", state, rl);
|
|
++vector;
|
|
}
|
|
|
|
printk("\n");
|
|
}
|
|
|
|
void dccp_ackpkts_print(const struct dccp_ackpkts *ap)
|
|
{
|
|
dccp_ackvector_print(ap->dccpap_buf_ackno,
|
|
ap->dccpap_buf + ap->dccpap_buf_head,
|
|
ap->dccpap_buf_vector_len);
|
|
}
|
|
#endif
|
|
|
|
static void dccp_ackpkts_trow_away_ack_record(struct dccp_ackpkts *ap)
|
|
{
|
|
/*
|
|
* As we're keeping track of the ack vector size
|
|
* (dccpap_buf_vector_len) and the sent ack vector size
|
|
* (dccpap_ack_vector_len) we don't need dccpap_buf_tail at all, but
|
|
* keep this code here as in the future we'll implement a vector of
|
|
* ack records, as suggested in draft-ietf-dccp-spec-11.txt
|
|
* Appendix A. -acme
|
|
*/
|
|
#if 0
|
|
ap->dccpap_buf_tail = ap->dccpap_ack_ptr + 1;
|
|
if (ap->dccpap_buf_tail >= ap->dccpap_buf_len)
|
|
ap->dccpap_buf_tail -= ap->dccpap_buf_len;
|
|
#endif
|
|
ap->dccpap_buf_vector_len -= ap->dccpap_ack_vector_len;
|
|
}
|
|
|
|
void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap, struct sock *sk,
|
|
u64 ackno)
|
|
{
|
|
/* Check if we actually sent an ACK vector */
|
|
if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
|
|
return;
|
|
|
|
if (ackno == ap->dccpap_ack_seqno) {
|
|
#ifdef CONFIG_IP_DCCP_DEBUG
|
|
struct dccp_sock *dp = dccp_sk(sk);
|
|
const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
|
|
"CLIENT rx ack: " : "server rx ack: ";
|
|
#endif
|
|
dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "
|
|
"ack_ackno=%llu, ACKED!\n",
|
|
debug_prefix, 1,
|
|
(unsigned long long) ap->dccpap_ack_seqno,
|
|
(unsigned long long) ap->dccpap_ack_ackno);
|
|
dccp_ackpkts_trow_away_ack_record(ap);
|
|
ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
|
|
}
|
|
}
|
|
|
|
static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
|
|
struct sock *sk, u64 ackno,
|
|
const unsigned char len,
|
|
const unsigned char *vector)
|
|
{
|
|
unsigned char i;
|
|
|
|
/* Check if we actually sent an ACK vector */
|
|
if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
|
|
return;
|
|
/*
|
|
* We're in the receiver half connection, so if the received an ACK
|
|
* vector ackno (e.g. 50) before dccpap_ack_seqno (e.g. 52), we're
|
|
* not interested.
|
|
*
|
|
* Extra explanation with example:
|
|
*
|
|
* if we received an ACK vector with ackno 50, it can only be acking
|
|
* 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent).
|
|
*/
|
|
/* dccp_pr_debug("is %llu < %llu? ", ackno, ap->dccpap_ack_seqno); */
|
|
if (before48(ackno, ap->dccpap_ack_seqno)) {
|
|
/* dccp_pr_debug_cat("yes\n"); */
|
|
return;
|
|
}
|
|
/* dccp_pr_debug_cat("no\n"); */
|
|
|
|
i = len;
|
|
while (i--) {
|
|
const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
|
|
u64 ackno_end_rl;
|
|
|
|
dccp_set_seqno(&ackno_end_rl, ackno - rl);
|
|
|
|
/*
|
|
* dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl,
|
|
* ap->dccpap_ack_seqno, ackno);
|
|
*/
|
|
if (between48(ap->dccpap_ack_seqno, ackno_end_rl, ackno)) {
|
|
const u8 state = (*vector &
|
|
DCCP_ACKPKTS_STATE_MASK) >> 6;
|
|
/* dccp_pr_debug_cat("yes\n"); */
|
|
|
|
if (state != DCCP_ACKPKTS_STATE_NOT_RECEIVED) {
|
|
#ifdef CONFIG_IP_DCCP_DEBUG
|
|
struct dccp_sock *dp = dccp_sk(sk);
|
|
const char *debug_prefix =
|
|
dp->dccps_role == DCCP_ROLE_CLIENT ?
|
|
"CLIENT rx ack: " : "server rx ack: ";
|
|
#endif
|
|
dccp_pr_debug("%sACK vector 0, len=%d, "
|
|
"ack_seqno=%llu, ack_ackno=%llu, "
|
|
"ACKED!\n",
|
|
debug_prefix, len,
|
|
(unsigned long long)
|
|
ap->dccpap_ack_seqno,
|
|
(unsigned long long)
|
|
ap->dccpap_ack_ackno);
|
|
dccp_ackpkts_trow_away_ack_record(ap);
|
|
}
|
|
/*
|
|
* If dccpap_ack_seqno was not received, no problem
|
|
* we'll send another ACK vector.
|
|
*/
|
|
ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
|
|
break;
|
|
}
|
|
/* dccp_pr_debug_cat("no\n"); */
|
|
|
|
dccp_set_seqno(&ackno, ackno_end_rl - 1);
|
|
++vector;
|
|
}
|
|
}
|