dccp: remove unused function argument
[linux-2.6.git] / net / dccp / options.c
index 0c996d8..4973bad 100644 (file)
 #include "dccp.h"
 #include "feat.h"
 
-int sysctl_dccp_feat_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW;
-int sysctl_dccp_feat_rx_ccid         = DCCPF_INITIAL_CCID;
-int sysctl_dccp_feat_tx_ccid         = DCCPF_INITIAL_CCID;
-int sysctl_dccp_feat_ack_ratio       = DCCPF_INITIAL_ACK_RATIO;
-int sysctl_dccp_feat_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR;
-int sysctl_dccp_feat_send_ndp_count  = DCCPF_INITIAL_SEND_NDP_COUNT;
-
-static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
+u64 dccp_decode_value_var(const u8 *bf, const u8 len)
 {
-       u32 value = 0;
+       u64 value = 0;
 
+       if (len >= DCCP_OPTVAL_MAXLEN)
+               value += ((u64)*bf++) << 40;
+       if (len > 4)
+               value += ((u64)*bf++) << 32;
        if (len > 3)
-               value += *bf++ << 24;
+               value += ((u64)*bf++) << 24;
        if (len > 2)
-               value += *bf++ << 16;
+               value += ((u64)*bf++) << 16;
        if (len > 1)
-               value += *bf++ << 8;
+               value += ((u64)*bf++) << 8;
        if (len > 0)
                value += *bf;
 
@@ -64,7 +61,7 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
                                        (dh->dccph_doff * 4);
        struct dccp_options_received *opt_recv = &dp->dccps_options_received;
        unsigned char opt, len;
-       unsigned char *value;
+       unsigned char *uninitialized_var(value);
        u32 elapsed_time;
        __be32 opt_val;
        int rc;
@@ -81,11 +78,11 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
                /* Check if this isn't a single byte option */
                if (opt > DCCPO_MAX_RESERVED) {
                        if (opt_ptr == opt_end)
-                               goto out_invalid_option;
+                               goto out_nonsensical_length;
 
                        len = *opt_ptr++;
-                       if (len < 3)
-                               goto out_invalid_option;
+                       if (len < 2)
+                               goto out_nonsensical_length;
                        /*
                         * Remove the type and len fields, leaving
                         * just the value size
@@ -95,7 +92,7 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
                        opt_ptr += len;
 
                        if (opt_ptr > opt_end)
-                               goto out_invalid_option;
+                               goto out_nonsensical_length;
                }
 
                /*
@@ -107,9 +104,11 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
                 *
                 * CCID-specific options are ignored during connection setup, as
                 * negotiation may still be in progress (see RFC 4340, 10.3).
+                * The same applies to Ack Vectors, as these depend on the CCID.
                 *
                 */
-               if (dreq != NULL && opt >= 128)
+               if (dreq != NULL && (opt >= 128 ||
+                   opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1))
                        goto ignore_option;
 
                switch (opt) {
@@ -122,44 +121,26 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
                                mandatory = 1;
                        break;
                case DCCPO_NDP_COUNT:
-                       if (len > 3)
+                       if (len > 6)
                                goto out_invalid_option;
 
                        opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
-                       dccp_pr_debug("%s rx opt: NDP count=%d\n", dccp_role(sk),
-                                     opt_recv->dccpor_ndp);
+                       dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk),
+                                     (unsigned long long)opt_recv->dccpor_ndp);
                        break;
-               case DCCPO_CHANGE_L:
-                       /* fall through */
-               case DCCPO_CHANGE_R:
-                       if (len < 2)
-                               goto out_invalid_option;
-                       rc = dccp_feat_change_recv(sk, opt, *value, value + 1,
-                                                  len - 1);
-                       /*
-                        * When there is a change error, change_recv is
-                        * responsible for dealing with it.  i.e. reply with an
-                        * empty confirm.
-                        * If the change was mandatory, then we need to die.
-                        */
-                       if (rc && mandatory)
-                               goto out_invalid_option;
-                       break;
-               case DCCPO_CONFIRM_L:
-                       /* fall through */
-               case DCCPO_CONFIRM_R:
-                       if (len < 2)
-                               goto out_invalid_option;
-                       if (dccp_feat_confirm_recv(sk, opt, *value,
-                                                  value + 1, len - 1))
-                               goto out_invalid_option;
+               case DCCPO_CHANGE_L ... DCCPO_CONFIRM_R:
+                       if (pkt_type == DCCP_PKT_DATA)      /* RFC 4340, 6 */
+                               break;
+                       rc = dccp_feat_parse_options(sk, dreq, mandatory, opt,
+                                                   *value, value + 1, len - 1);
+                       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 (dccp_msk(sk)->dccpms_send_ack_vector &&
+                       if (dp->dccps_hc_rx_ackvec != NULL &&
                            dccp_ackvec_parse(sk, skb, &ackno, opt, value, len))
                                goto out_invalid_option;
                        break;
@@ -277,20 +258,30 @@ ignore_option:
        if (mandatory)
                goto out_invalid_option;
 
+out_nonsensical_length:
+       /* RFC 4340, 5.8: ignore option and all remaining option space */
        return 0;
 
 out_invalid_option:
        DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT);
-       DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR;
-       DCCP_WARN("DCCP(%p): invalid option %d, len=%d", sk, opt, len);
+       rc = DCCP_RESET_CODE_OPTION_ERROR;
+out_featneg_failed:
+       DCCP_WARN("DCCP(%p): Option %d (len=%d) error=%u\n", sk, opt, len, rc);
+       DCCP_SKB_CB(skb)->dccpd_reset_code = rc;
+       DCCP_SKB_CB(skb)->dccpd_reset_data[0] = opt;
+       DCCP_SKB_CB(skb)->dccpd_reset_data[1] = len > 0 ? value[0] : 0;
+       DCCP_SKB_CB(skb)->dccpd_reset_data[2] = len > 1 ? value[1] : 0;
        return -1;
 }
 
 EXPORT_SYMBOL_GPL(dccp_parse_options);
 
-static void dccp_encode_value_var(const u32 value, unsigned char *to,
-                                 const unsigned int len)
+void dccp_encode_value_var(const u64 value, u8 *to, const u8 len)
 {
+       if (len >= DCCP_OPTVAL_MAXLEN)
+               *to++ = (value & 0xFF0000000000ull) >> 40;
+       if (len > 4)
+               *to++ = (value & 0xFF00000000ull) >> 32;
        if (len > 3)
                *to++ = (value & 0xFF000000) >> 24;
        if (len > 2)
@@ -301,14 +292,15 @@ static void dccp_encode_value_var(const u32 value, unsigned char *to,
                *to++ = (value & 0xFF);
 }
 
-static inline int dccp_ndp_len(const int ndp)
+static inline u8 dccp_ndp_len(const u64 ndp)
 {
-       return likely(ndp <= 0xFF) ? 1 : ndp <= 0xFFFF ? 2 : 3;
+       if (likely(ndp <= 0xFF))
+               return 1;
+       return likely(ndp <= USHRT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6);
 }
 
-int dccp_insert_option(struct sock *sk, struct sk_buff *skb,
-                       const unsigned char option,
-                       const void *value, const unsigned char len)
+int dccp_insert_option(struct sk_buff *skb, const unsigned char option,
+                      const void *value, const unsigned char len)
 {
        unsigned char *to;
 
@@ -330,7 +322,7 @@ EXPORT_SYMBOL_GPL(dccp_insert_option);
 static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb)
 {
        struct dccp_sock *dp = dccp_sk(sk);
-       int ndp = dp->dccps_ndp_count;
+       u64 ndp = dp->dccps_ndp_count;
 
        if (dccp_non_data_packet(skb))
                ++dp->dccps_ndp_count;
@@ -361,8 +353,7 @@ static inline int dccp_elapsed_time_len(const u32 elapsed_time)
        return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
 }
 
-int dccp_insert_option_elapsed_time(struct sock *sk, struct sk_buff *skb,
-                                   u32 elapsed_time)
+int dccp_insert_option_elapsed_time(struct sk_buff *skb, u32 elapsed_time)
 {
        const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
        const int len = 2 + elapsed_time_len;
@@ -393,13 +384,13 @@ int dccp_insert_option_elapsed_time(struct sock *sk, struct sk_buff *skb,
 
 EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);
 
-int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
+int dccp_insert_option_timestamp(struct sk_buff *skb)
 {
        __be32 now = htonl(dccp_timestamp());
        /* yes this will overflow but that is the point as we want a
         * 10 usec 32 bit timer which mean it wraps every 11.9 hours */
 
-       return dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now));
+       return dccp_insert_option(skb, DCCPO_TIMESTAMP, &now, sizeof(now));
 }
 
 EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);
@@ -448,111 +439,106 @@ static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
        return 0;
 }
 
-static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat,
-                               u8 *val, u8 len)
+/**
+ * dccp_insert_option_mandatory  -  Mandatory option (5.8.2)
+ * Note that since we are using skb_push, this function needs to be called
+ * _after_ inserting the option it is supposed to influence (stack order).
+ */
+int dccp_insert_option_mandatory(struct sk_buff *skb)
 {
-       u8 *to;
+       if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN)
+               return -1;
 
-       if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 3 > DCCP_MAX_OPT_LEN) {
-               DCCP_WARN("packet too small for feature %d option!\n", feat);
+       DCCP_SKB_CB(skb)->dccpd_opt_len++;
+       *skb_push(skb, 1) = DCCPO_MANDATORY;
+       return 0;
+}
+
+/**
+ * dccp_insert_fn_opt  -  Insert single Feature-Negotiation option into @skb
+ * @type: %DCCPO_CHANGE_L, %DCCPO_CHANGE_R, %DCCPO_CONFIRM_L, %DCCPO_CONFIRM_R
+ * @feat: one out of %dccp_feature_numbers
+ * @val: NN value or SP array (preferred element first) to copy
+ * @len: true length of @val in bytes (excluding first element repetition)
+ * @repeat_first: whether to copy the first element of @val twice
+ * The last argument is used to construct Confirm options, where the preferred
+ * value and the preference list appear separately (RFC 4340, 6.3.1). Preference
+ * lists are kept such that the preferred entry is always first, so we only need
+ * to copy twice, and avoid the overhead of cloning into a bigger array.
+ */
+int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat,
+                      u8 *val, u8 len, bool repeat_first)
+{
+       u8 tot_len, *to;
+
+       /* take the `Feature' field and possible repetition into account */
+       if (len > (DCCP_SINGLE_OPT_MAXLEN - 2)) {
+               DCCP_WARN("length %u for feature %u too large\n", len, feat);
                return -1;
        }
 
-       DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3;
+       if (unlikely(val == NULL || len == 0))
+               len = repeat_first = 0;
+       tot_len = 3 + repeat_first + len;
+
+       if (DCCP_SKB_CB(skb)->dccpd_opt_len + tot_len > DCCP_MAX_OPT_LEN) {
+               DCCP_WARN("packet too small for feature %d option!\n", feat);
+               return -1;
+       }
+       DCCP_SKB_CB(skb)->dccpd_opt_len += tot_len;
 
-       to    = skb_push(skb, len + 3);
+       to    = skb_push(skb, tot_len);
        *to++ = type;
-       *to++ = len + 3;
+       *to++ = tot_len;
        *to++ = feat;
 
+       if (repeat_first)
+               *to++ = *val;
        if (len)
                memcpy(to, val, len);
-
-       dccp_pr_debug("%s(%s (%d), ...), length %d\n",
-                     dccp_feat_typename(type),
-                     dccp_feat_name(feat), feat, len);
        return 0;
 }
 
-static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb)
+/* The length of all options needs to be a multiple of 4 (5.8) */
+static void dccp_insert_option_padding(struct sk_buff *skb)
 {
-       struct dccp_sock *dp = dccp_sk(sk);
-       struct dccp_minisock *dmsk = dccp_msk(sk);
-       struct dccp_opt_pend *opt, *next;
-       int change = 0;
-
-       /* confirm any options [NN opts] */
-       list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) {
-               dccp_insert_feat_opt(skb, opt->dccpop_type,
-                                    opt->dccpop_feat, opt->dccpop_val,
-                                    opt->dccpop_len);
-               /* fear empty confirms */
-               if (opt->dccpop_val)
-                       kfree(opt->dccpop_val);
-               kfree(opt);
-       }
-       INIT_LIST_HEAD(&dmsk->dccpms_conf);
-
-       /* see which features we need to send */
-       list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
-               /* see if we need to send any confirm */
-               if (opt->dccpop_sc) {
-                       dccp_insert_feat_opt(skb, opt->dccpop_type + 1,
-                                            opt->dccpop_feat,
-                                            opt->dccpop_sc->dccpoc_val,
-                                            opt->dccpop_sc->dccpoc_len);
-
-                       BUG_ON(!opt->dccpop_sc->dccpoc_val);
-                       kfree(opt->dccpop_sc->dccpoc_val);
-                       kfree(opt->dccpop_sc);
-                       opt->dccpop_sc = NULL;
-               }
+       int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
 
-               /* any option not confirmed, re-send it */
-               if (!opt->dccpop_conf) {
-                       dccp_insert_feat_opt(skb, opt->dccpop_type,
-                                            opt->dccpop_feat, opt->dccpop_val,
-                                            opt->dccpop_len);
-                       change++;
-               }
-       }
-
-       /* Retransmit timer.
-        * If this is the master listening sock, we don't set a timer on it.  It
-        * should be fine because if the dude doesn't receive our RESPONSE
-        * [which will contain the CHANGE] he will send another REQUEST which
-        * will "retrnasmit" the change.
-        */
-       if (change && dp->dccps_role != DCCP_ROLE_LISTEN) {
-               dccp_pr_debug("reset feat negotiation timer %p\n", sk);
-
-               /* XXX don't reset the timer on re-transmissions.  I.e. reset it
-                * only when sending new stuff i guess.  Currently the timer
-                * never backs off because on re-transmission it just resets it!
-                */
-               inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
-                                         inet_csk(sk)->icsk_rto, DCCP_RTO_MAX);
+       if (padding != 0) {
+               padding = 4 - padding;
+               memset(skb_push(skb, padding), 0, padding);
+               DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
        }
-
-       return 0;
 }
 
 int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
 {
        struct dccp_sock *dp = dccp_sk(sk);
-       struct dccp_minisock *dmsk = dccp_msk(sk);
 
        DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
 
-       if (dmsk->dccpms_send_ndp_count &&
-           dccp_insert_option_ndp(sk, skb))
+       if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb))
                return -1;
 
-       if (!dccp_packet_without_ack(skb)) {
-               if (dmsk->dccpms_send_ack_vector &&
-                   dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
-                   dccp_insert_option_ackvec(sk, skb))
+       if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) {
+
+               /* Feature Negotiation */
+               if (dccp_feat_insert_opts(dp, NULL, skb))
                        return -1;
+
+               if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) {
+                       /*
+                        * Obtain RTT sample from Request/Response exchange.
+                        * This is currently used in CCID 3 initialisation.
+                        */
+                       if (dccp_insert_option_timestamp(skb))
+                               return -1;
+
+               } else if (dp->dccps_hc_rx_ackvec != NULL &&
+                          dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
+                          dccp_insert_option_ackvec(sk, skb)) {
+                               return -1;
+               }
        }
 
        if (dp->dccps_hc_rx_insert_options) {
@@ -561,37 +547,25 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
                dp->dccps_hc_rx_insert_options = 0;
        }
 
-       /* Feature negotiation */
-       /* Data packets can't do feat negotiation */
-       if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA &&
-           DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATAACK &&
-           dccp_insert_options_feat(sk, skb))
-               return -1;
-
-       /*
-        * Obtain RTT sample from Request/Response exchange.
-        * This is currently used in CCID 3 initialisation.
-        */
-       if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST &&
-           dccp_insert_option_timestamp(sk, skb))
-               return -1;
-
        if (dp->dccps_timestamp_echo != 0 &&
            dccp_insert_option_timestamp_echo(dp, NULL, skb))
                return -1;
 
-       /* XXX: insert other options when appropriate */
+       dccp_insert_option_padding(skb);
+       return 0;
+}
+
+int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
+{
+       DCCP_SKB_CB(skb)->dccpd_opt_len = 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;
+       if (dccp_feat_insert_opts(NULL, dreq, skb))
+               return -1;
 
-               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;
 }