struct dccp_sock *dp = dccp_sk(sk);
const struct dccp_hdr *dh = dccp_hdr(skb);
const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
- u64 ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq;
unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
unsigned char *opt_ptr = options;
const unsigned char *opt_end = (unsigned char *)dh +
if (rc)
goto out_featneg_failed;
break;
- case DCCPO_ACK_VECTOR_0:
- case DCCPO_ACK_VECTOR_1:
- if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
- break;
- if (dp->dccps_hc_rx_ackvec != NULL &&
- dccp_ackvec_parse(sk, skb, &ackno, opt, value, len))
- goto out_invalid_option;
- break;
case DCCPO_TIMESTAMP:
if (len != 4)
goto out_invalid_option;
pkt_type, opt, value, len))
goto out_invalid_option;
break;
+ case DCCPO_ACK_VECTOR_0:
+ case DCCPO_ACK_VECTOR_1:
+ if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
+ break;
+ /*
+ * Ack vectors are processed by the TX CCID if it is
+ * interested. The RX CCID need not parse Ack Vectors,
+ * since it is only interested in clearing old state.
+ * Fall through.
+ */
case DCCPO_MIN_TX_CCID_SPECIFIC ... DCCPO_MAX_TX_CCID_SPECIFIC:
if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
pkt_type, opt, value, len))
return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
}
+/* FIXME: This function is currently not used anywhere */
int dccp_insert_option_elapsed_time(struct sk_buff *skb, u32 elapsed_time)
{
const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
return 0;
}
+static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
+ struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
+ const u16 buflen = dccp_ackvec_buflen(av);
+ /* Figure out how many options do we need to represent the ackvec */
+ const u8 nr_opts = DIV_ROUND_UP(buflen, DCCP_SINGLE_OPT_MAXLEN);
+ u16 len = buflen + 2 * nr_opts;
+ u8 i, nonce = 0;
+ const unsigned char *tail, *from;
+ unsigned char *to;
+
+ if (dcb->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
+ DCCP_WARN("Lacking space for %u bytes on %s packet\n", len,
+ dccp_packet_name(dcb->dccpd_type));
+ return -1;
+ }
+ /*
+ * Since Ack Vectors are variable-length, we can not always predict
+ * their size. To catch exception cases where the space is running out
+ * on the skb, a separate Sync is scheduled to carry the Ack Vector.
+ */
+ if (len > DCCPAV_MIN_OPTLEN &&
+ len + dcb->dccpd_opt_len + skb->len > dp->dccps_mss_cache) {
+ DCCP_WARN("No space left for Ack Vector (%u) on skb (%u+%u), "
+ "MPS=%u ==> reduce payload size?\n", len, skb->len,
+ dcb->dccpd_opt_len, dp->dccps_mss_cache);
+ dp->dccps_sync_scheduled = 1;
+ return 0;
+ }
+ dcb->dccpd_opt_len += len;
+
+ to = skb_push(skb, len);
+ len = buflen;
+ from = av->av_buf + av->av_buf_head;
+ tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
+
+ for (i = 0; i < nr_opts; ++i) {
+ int copylen = len;
+
+ if (len > DCCP_SINGLE_OPT_MAXLEN)
+ copylen = DCCP_SINGLE_OPT_MAXLEN;
+
+ /*
+ * RFC 4340, 12.2: Encode the Nonce Echo for this Ack Vector via
+ * its type; ack_nonce is the sum of all individual buf_nonce's.
+ */
+ nonce ^= av->av_buf_nonce[i];
+
+ *to++ = DCCPO_ACK_VECTOR_0 + av->av_buf_nonce[i];
+ *to++ = copylen + 2;
+
+ /* Check if buf_head wraps */
+ if (from + copylen > tail) {
+ const u16 tailsize = tail - from;
+
+ memcpy(to, from, tailsize);
+ to += tailsize;
+ len -= tailsize;
+ copylen -= tailsize;
+ from = av->av_buf;
+ }
+
+ memcpy(to, from, copylen);
+ from += copylen;
+ to += copylen;
+ len -= copylen;
+ }
+ /*
+ * Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
+ */
+ if (dccp_ackvec_update_records(av, dcb->dccpd_seq, nonce))
+ return -ENOBUFS;
+ return 0;
+}
+
/**
* dccp_insert_option_mandatory - Mandatory option (5.8.2)
* Note that since we are using skb_push, this function needs to be called
if (dccp_insert_option_timestamp(skb))
return -1;
- } else if (dp->dccps_hc_rx_ackvec != NULL &&
- dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
+ } else if (dccp_ackvec_pending(sk) &&
dccp_insert_option_ackvec(sk, skb)) {
return -1;
}
projects / mv-sheeva.git / blobdiff