- Update to 2.6.25-rc3.
[linux-flexiantxendom0-3.2.10.git] / net / dccp / options.c
index d286cff..d2a84a2 100644 (file)
@@ -46,7 +46,13 @@ static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
        return value;
 }
 
-int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
+/**
+ * dccp_parse_options  -  Parse DCCP options present in @skb
+ * @sk: client|server|listening dccp socket (when @dreq != NULL)
+ * @dreq: request socket to use during connection setup, or NULL
+ */
+int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
+                      struct sk_buff *skb)
 {
        struct dccp_sock *dp = dccp_sk(sk);
        const struct dccp_hdr *dh = dccp_hdr(skb);
@@ -92,6 +98,20 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
                                goto out_invalid_option;
                }
 
+               /*
+                * CCID-Specific Options (from RFC 4340, sec. 10.3):
+                *
+                * Option numbers 128 through 191 are for options sent from the
+                * HC-Sender to the HC-Receiver; option numbers 192 through 255
+                * are for options sent from the HC-Receiver to the HC-Sender.
+                *
+                * CCID-specific options are ignored during connection setup, as
+                * negotiation may still be in progress (see RFC 4340, 10.3).
+                *
+                */
+               if (dreq != NULL && opt >= 128)
+                       goto ignore_option;
+
                switch (opt) {
                case DCCPO_PADDING:
                        break;
@@ -112,6 +132,8 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
                case DCCPO_CHANGE_L:
                        /* fall through */
                case DCCPO_CHANGE_R:
+                       if (pkt_type == DCCP_PKT_DATA)
+                               break;
                        if (len < 2)
                                goto out_invalid_option;
                        rc = dccp_feat_change_recv(sk, opt, *value, value + 1,
@@ -128,7 +150,9 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
                case DCCPO_CONFIRM_L:
                        /* fall through */
                case DCCPO_CONFIRM_R:
-                       if (len < 2)
+                       if (pkt_type == DCCP_PKT_DATA)
+                               break;
+                       if (len < 2)    /* FIXME this disallows empty confirm */
                                goto out_invalid_option;
                        if (dccp_feat_confirm_recv(sk, opt, *value,
                                                   value + 1, len - 1))
@@ -136,7 +160,7 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
                        break;
                case DCCPO_ACK_VECTOR_0:
                case DCCPO_ACK_VECTOR_1:
-                       if (pkt_type == DCCP_PKT_DATA)
+                       if (dccp_packet_without_ack(skb))   /* RFC 4340, 11.4 */
                                break;
 
                        if (dccp_msk(sk)->dccpms_send_ack_vector &&
@@ -146,15 +170,27 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
                case DCCPO_TIMESTAMP:
                        if (len != 4)
                                goto out_invalid_option;
-
+                       /*
+                        * RFC 4340 13.1: "The precise time corresponding to
+                        * Timestamp Value zero is not specified". We use
+                        * zero to indicate absence of a meaningful timestamp.
+                        */
                        opt_val = get_unaligned((__be32 *)value);
-                       opt_recv->dccpor_timestamp = ntohl(opt_val);
-
-                       dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp;
-                       dp->dccps_timestamp_time = ktime_get_real();
+                       if (unlikely(opt_val == 0)) {
+                               DCCP_WARN("Timestamp with zero value\n");
+                               break;
+                       }
 
+                       if (dreq != NULL) {
+                               dreq->dreq_timestamp_echo = ntohl(opt_val);
+                               dreq->dreq_timestamp_time = dccp_timestamp();
+                       } else {
+                               opt_recv->dccpor_timestamp =
+                                       dp->dccps_timestamp_echo = ntohl(opt_val);
+                               dp->dccps_timestamp_time = dccp_timestamp();
+                       }
                        dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n",
-                                     dccp_role(sk), opt_recv->dccpor_timestamp,
+                                     dccp_role(sk), ntohl(opt_val),
                                      (unsigned long long)
                                      DCCP_SKB_CB(skb)->dccpd_ack_seq);
                        break;
@@ -194,18 +230,17 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
                                opt_recv->dccpor_elapsed_time = elapsed_time;
                        break;
                case DCCPO_ELAPSED_TIME:
-                       if (len != 2 && len != 4)
-                               goto out_invalid_option;
-
-                       if (pkt_type == DCCP_PKT_DATA)
-                               continue;
+                       if (dccp_packet_without_ack(skb))   /* RFC 4340, 13.2 */
+                               break;
 
                        if (len == 2) {
                                __be16 opt_val2 = get_unaligned((__be16 *)value);
                                elapsed_time = ntohs(opt_val2);
-                       } else {
+                       } else if (len == 4) {
                                opt_val = get_unaligned((__be32 *)value);
                                elapsed_time = ntohl(opt_val);
+                       } else {
+                               goto out_invalid_option;
                        }
 
                        if (elapsed_time > opt_recv->dccpor_elapsed_time)
@@ -214,15 +249,6 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
                        dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
                                      dccp_role(sk), elapsed_time);
                        break;
-                       /*
-                        * From RFC 4340, sec. 10.3:
-                        *
-                        *      Option numbers 128 through 191 are for
-                        *      options sent from the HC-Sender to the
-                        *      HC-Receiver; option numbers 192 through 255
-                        *      are for options sent from the HC-Receiver to
-                        *      the HC-Sender.
-                        */
                case 128 ... 191: {
                        const u16 idx = value - options;
 
@@ -246,7 +272,7 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
                                  "implemented, ignoring", sk, opt, len);
                        break;
                }
-
+ignore_option:
                if (opt != DCCPO_MANDATORY)
                        mandatory = 0;
        }
@@ -382,16 +408,24 @@ int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
 
 EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);
 
-static int dccp_insert_option_timestamp_echo(struct sock *sk,
+static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
+                                            struct dccp_request_sock *dreq,
                                             struct sk_buff *skb)
 {
-       struct dccp_sock *dp = dccp_sk(sk);
        __be32 tstamp_echo;
-       int len, elapsed_time_len;
        unsigned char *to;
-       const suseconds_t delta = ktime_us_delta(ktime_get_real(),
-                                                dp->dccps_timestamp_time);
-       u32 elapsed_time = delta / 10;
+       u32 elapsed_time, elapsed_time_len, len;
+
+       if (dreq != NULL) {
+               elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time;
+               tstamp_echo  = htonl(dreq->dreq_timestamp_echo);
+               dreq->dreq_timestamp_echo = 0;
+       } else {
+               elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time;
+               tstamp_echo  = htonl(dp->dccps_timestamp_echo);
+               dp->dccps_timestamp_echo = 0;
+       }
+
        elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
        len = 6 + elapsed_time_len;
 
@@ -404,7 +438,6 @@ static int dccp_insert_option_timestamp_echo(struct sock *sk,
        *to++ = DCCPO_TIMESTAMP_ECHO;
        *to++ = len;
 
-       tstamp_echo = htonl(dp->dccps_timestamp_echo);
        memcpy(to, &tstamp_echo, 4);
        to += 4;
 
@@ -416,8 +449,6 @@ static int dccp_insert_option_timestamp_echo(struct sock *sk,
                memcpy(to, &var32, 4);
        }
 
-       dp->dccps_timestamp_echo = 0;
-       dp->dccps_timestamp_time = ktime_set(0, 0);
        return 0;
 }
 
@@ -510,6 +541,18 @@ static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb)
        return 0;
 }
 
+/* The length of all options needs to be a multiple of 4 (5.8) */
+static void dccp_insert_option_padding(struct sk_buff *skb)
+{
+       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;
+       }
+}
+
 int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
 {
        struct dccp_sock *dp = dccp_sk(sk);
@@ -526,10 +569,6 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
                    dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
                    dccp_insert_option_ackvec(sk, skb))
                        return -1;
-
-               if (dp->dccps_timestamp_echo != 0 &&
-                   dccp_insert_option_timestamp_echo(sk, skb))
-                       return -1;
        }
 
        if (dp->dccps_hc_rx_insert_options) {
@@ -553,18 +592,22 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
            dccp_insert_option_timestamp(sk, skb))
                return -1;
 
-       /* XXX: insert other options when appropriate */
+       if (dp->dccps_timestamp_echo != 0 &&
+           dccp_insert_option_timestamp_echo(dp, NULL, skb))
+               return -1;
+
+       dccp_insert_option_padding(skb);
+       return 0;
+}
 
-       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;
+int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
+{
+       DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
 
-               if (padding != 0) {
-                       padding = 4 - padding;
-                       memset(skb_push(skb, padding), 0, padding);
-                       DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
-               }
-       }
+       if (dreq->dreq_timestamp_echo != 0 &&
+           dccp_insert_option_timestamp_echo(NULL, dreq, skb))
+               return -1;
 
+       dccp_insert_option_padding(skb);
        return 0;
 }