diff options
Diffstat (limited to 'net/dccp/feat.c')
| -rw-r--r-- | net/dccp/feat.c | 466 |
1 files changed, 393 insertions, 73 deletions
diff --git a/net/dccp/feat.c b/net/dccp/feat.c index 4152308958a..9733ddbc96c 100644 --- a/net/dccp/feat.c +++ b/net/dccp/feat.c @@ -12,6 +12,7 @@ * ----------- * o Feature negotiation is coordinated with connection setup (as in TCP), wild * changes of parameters of an established connection are not supported. + * o Changing non-negotiable (NN) values is supported in state OPEN/PARTOPEN. * o All currently known SP features have 1-byte quantities. If in the future * extensions of RFCs 4340..42 define features with item lengths larger than * one byte, a feature-specific extension of the code will be required. @@ -22,9 +23,15 @@ * 2 of the License, or (at your option) any later version. */ #include <linux/module.h> +#include <linux/slab.h> #include "ccid.h" #include "feat.h" +/* feature-specific sysctls - initialised to the defaults from RFC 4340, 6.4 */ +unsigned long sysctl_dccp_sequence_window __read_mostly = 100; +int sysctl_dccp_rx_ccid __read_mostly = 2, + sysctl_dccp_tx_ccid __read_mostly = 2; + /* * Feature activation handlers. * @@ -51,8 +58,17 @@ static int dccp_hdlr_ccid(struct sock *sk, u64 ccid, bool rx) static int dccp_hdlr_seq_win(struct sock *sk, u64 seq_win, bool rx) { - if (!rx) - dccp_msk(sk)->dccpms_sequence_window = seq_win; + struct dccp_sock *dp = dccp_sk(sk); + + if (rx) { + dp->dccps_r_seq_win = seq_win; + /* propagate changes to update SWL/SWH */ + dccp_update_gsr(sk, dp->dccps_gsr); + } else { + dp->dccps_l_seq_win = seq_win; + /* propagate changes to update AWL */ + dccp_update_gss(sk, dp->dccps_gss); + } return 0; } @@ -194,6 +210,101 @@ static int dccp_feat_default_value(u8 feat_num) return idx < 0 ? 0 : dccp_feat_table[idx].default_value; } +/* + * Debugging and verbose-printing section + */ +static const char *dccp_feat_fname(const u8 feat) +{ + static const char *const feature_names[] = { + [DCCPF_RESERVED] = "Reserved", + [DCCPF_CCID] = "CCID", + [DCCPF_SHORT_SEQNOS] = "Allow Short Seqnos", + [DCCPF_SEQUENCE_WINDOW] = "Sequence Window", + [DCCPF_ECN_INCAPABLE] = "ECN Incapable", + [DCCPF_ACK_RATIO] = "Ack Ratio", + [DCCPF_SEND_ACK_VECTOR] = "Send ACK Vector", + [DCCPF_SEND_NDP_COUNT] = "Send NDP Count", + [DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage", + [DCCPF_DATA_CHECKSUM] = "Send Data Checksum", + }; + if (feat > DCCPF_DATA_CHECKSUM && feat < DCCPF_MIN_CCID_SPECIFIC) + return feature_names[DCCPF_RESERVED]; + + if (feat == DCCPF_SEND_LEV_RATE) + return "Send Loss Event Rate"; + if (feat >= DCCPF_MIN_CCID_SPECIFIC) + return "CCID-specific"; + + return feature_names[feat]; +} + +static const char *const dccp_feat_sname[] = { + "DEFAULT", "INITIALISING", "CHANGING", "UNSTABLE", "STABLE", +}; + +#ifdef CONFIG_IP_DCCP_DEBUG +static const char *dccp_feat_oname(const u8 opt) +{ + switch (opt) { + case DCCPO_CHANGE_L: return "Change_L"; + case DCCPO_CONFIRM_L: return "Confirm_L"; + case DCCPO_CHANGE_R: return "Change_R"; + case DCCPO_CONFIRM_R: return "Confirm_R"; + } + return NULL; +} + +static void dccp_feat_printval(u8 feat_num, dccp_feat_val const *val) +{ + u8 i, type = dccp_feat_type(feat_num); + + if (val == NULL || (type == FEAT_SP && val->sp.vec == NULL)) + dccp_pr_debug_cat("(NULL)"); + else if (type == FEAT_SP) + for (i = 0; i < val->sp.len; i++) + dccp_pr_debug_cat("%s%u", i ? " " : "", val->sp.vec[i]); + else if (type == FEAT_NN) + dccp_pr_debug_cat("%llu", (unsigned long long)val->nn); + else + dccp_pr_debug_cat("unknown type %u", type); +} + +static void dccp_feat_printvals(u8 feat_num, u8 *list, u8 len) +{ + u8 type = dccp_feat_type(feat_num); + dccp_feat_val fval = { .sp.vec = list, .sp.len = len }; + + if (type == FEAT_NN) + fval.nn = dccp_decode_value_var(list, len); + dccp_feat_printval(feat_num, &fval); +} + +static void dccp_feat_print_entry(struct dccp_feat_entry const *entry) +{ + dccp_debug(" * %s %s = ", entry->is_local ? "local" : "remote", + dccp_feat_fname(entry->feat_num)); + dccp_feat_printval(entry->feat_num, &entry->val); + dccp_pr_debug_cat(", state=%s %s\n", dccp_feat_sname[entry->state], + entry->needs_confirm ? "(Confirm pending)" : ""); +} + +#define dccp_feat_print_opt(opt, feat, val, len, mandatory) do { \ + dccp_pr_debug("%s(%s, ", dccp_feat_oname(opt), dccp_feat_fname(feat));\ + dccp_feat_printvals(feat, val, len); \ + dccp_pr_debug_cat(") %s\n", mandatory ? "!" : ""); } while (0) + +#define dccp_feat_print_fnlist(fn_list) { \ + const struct dccp_feat_entry *___entry; \ + \ + dccp_pr_debug("List Dump:\n"); \ + list_for_each_entry(___entry, fn_list, node) \ + dccp_feat_print_entry(___entry); \ +} +#else /* ! CONFIG_IP_DCCP_DEBUG */ +#define dccp_feat_print_opt(opt, feat, val, len, mandatory) +#define dccp_feat_print_fnlist(fn_list) +#endif + static int __dccp_feat_activate(struct sock *sk, const int idx, const bool is_local, dccp_feat_val const *fval) { @@ -226,9 +337,28 @@ static int __dccp_feat_activate(struct sock *sk, const int idx, /* Location is RX if this is a local-RX or remote-TX feature */ rx = (is_local == (dccp_feat_table[idx].rxtx == FEAT_AT_RX)); + dccp_debug(" -> activating %s %s, %sval=%llu\n", rx ? "RX" : "TX", + dccp_feat_fname(dccp_feat_table[idx].feat_num), + fval ? "" : "default ", (unsigned long long)val); + return dccp_feat_table[idx].activation_hdlr(sk, val, rx); } +/** + * dccp_feat_activate - Activate feature value on socket + * @sk: fully connected DCCP socket (after handshake is complete) + * @feat_num: feature to activate, one of %dccp_feature_numbers + * @local: whether local (1) or remote (0) @feat_num is meant + * @fval: the value (SP or NN) to activate, or NULL to use the default value + * + * For general use this function is preferable over __dccp_feat_activate(). + */ +static int dccp_feat_activate(struct sock *sk, u8 feat_num, bool local, + dccp_feat_val const *fval) +{ + return __dccp_feat_activate(sk, dccp_feat_index(feat_num), local, fval); +} + /* Test for "Req'd" feature (RFC 4340, 6.4) */ static inline int dccp_feat_must_be_understood(u8 feat_num) { @@ -317,6 +447,7 @@ static struct dccp_feat_entry *dccp_feat_list_lookup(struct list_head *fn_list, * @head: list to add to * @feat: feature number * @local: whether the local (1) or remote feature with number @feat is meant + * * This is the only constructor and serves to ensure the above invariants. */ static struct dccp_feat_entry * @@ -361,8 +492,8 @@ static int dccp_feat_push_change(struct list_head *fn_list, u8 feat, u8 local, new->feat_num = feat; new->is_local = local; new->state = FEAT_INITIALISING; - new->needs_confirm = 0; - new->empty_confirm = 0; + new->needs_confirm = false; + new->empty_confirm = false; new->val = *fval; new->needs_mandatory = mandatory; @@ -375,6 +506,7 @@ static int dccp_feat_push_change(struct list_head *fn_list, u8 feat, u8 local, * @feat: one of %dccp_feature_numbers * @local: whether local (1) or remote (0) @feat_num is being confirmed * @fval: pointer to NN/SP value to be inserted or NULL + * * Returns 0 on success, a Reset code for further processing otherwise. */ static int dccp_feat_push_confirm(struct list_head *fn_list, u8 feat, u8 local, @@ -388,12 +520,12 @@ static int dccp_feat_push_confirm(struct list_head *fn_list, u8 feat, u8 local, new->feat_num = feat; new->is_local = local; new->state = FEAT_STABLE; /* transition in 6.6.2 */ - new->needs_confirm = 1; + new->needs_confirm = true; new->empty_confirm = (fval == NULL); new->val.nn = 0; /* zeroes the whole structure */ if (!new->empty_confirm) new->val = *fval; - new->needs_mandatory = 0; + new->needs_mandatory = false; return 0; } @@ -530,16 +662,28 @@ int dccp_feat_insert_opts(struct dccp_sock *dp, struct dccp_request_sock *dreq, return -1; } } + dccp_feat_print_opt(opt, pos->feat_num, ptr, len, 0); if (dccp_insert_fn_opt(skb, opt, pos->feat_num, ptr, len, rpt)) return -1; if (pos->needs_mandatory && dccp_insert_option_mandatory(skb)) return -1; - /* - * Enter CHANGING after transmitting the Change option (6.6.2). - */ - if (pos->state == FEAT_INITIALISING) - pos->state = FEAT_CHANGING; + + if (skb->sk->sk_state == DCCP_OPEN && + (opt == DCCPO_CONFIRM_R || opt == DCCPO_CONFIRM_L)) { + /* + * Confirms don't get retransmitted (6.6.3) once the + * connection is in state OPEN + */ + dccp_feat_list_pop(pos); + } else { + /* + * Enter CHANGING after transmitting the Change + * option (6.6.2). + */ + if (pos->state == FEAT_INITIALISING) + pos->state = FEAT_CHANGING; + } } return 0; } @@ -550,6 +694,7 @@ int dccp_feat_insert_opts(struct dccp_sock *dp, struct dccp_request_sock *dreq, * @feat: an NN feature from %dccp_feature_numbers * @mandatory: use Mandatory option if 1 * @nn_val: value to register (restricted to 4 bytes) + * * Note that NN features are local by definition (RFC 4340, 6.3.2). */ static int __feat_register_nn(struct list_head *fn, u8 feat, @@ -615,16 +760,72 @@ int dccp_feat_register_sp(struct sock *sk, u8 feat, u8 is_local, 0, list, len); } -/* Analogous to dccp_feat_register_sp(), but for non-negotiable values */ -int dccp_feat_register_nn(struct sock *sk, u8 feat, u64 val) +/** + * dccp_feat_nn_get - Query current/pending value of NN feature + * @sk: DCCP socket of an established connection + * @feat: NN feature number from %dccp_feature_numbers + * + * For a known NN feature, returns value currently being negotiated, or + * current (confirmed) value if no negotiation is going on. + */ +u64 dccp_feat_nn_get(struct sock *sk, u8 feat) { - /* any changes must be registered before establishing the connection */ - if (sk->sk_state != DCCP_CLOSED) - return -EISCONN; - if (dccp_feat_type(feat) != FEAT_NN) + if (dccp_feat_type(feat) == FEAT_NN) { + struct dccp_sock *dp = dccp_sk(sk); + struct dccp_feat_entry *entry; + + entry = dccp_feat_list_lookup(&dp->dccps_featneg, feat, 1); + if (entry != NULL) + return entry->val.nn; + + switch (feat) { + case DCCPF_ACK_RATIO: + return dp->dccps_l_ack_ratio; + case DCCPF_SEQUENCE_WINDOW: + return dp->dccps_l_seq_win; + } + } + DCCP_BUG("attempt to look up unsupported feature %u", feat); + return 0; +} +EXPORT_SYMBOL_GPL(dccp_feat_nn_get); + +/** + * dccp_feat_signal_nn_change - Update NN values for an established connection + * @sk: DCCP socket of an established connection + * @feat: NN feature number from %dccp_feature_numbers + * @nn_val: the new value to use + * + * This function is used to communicate NN updates out-of-band. + */ +int dccp_feat_signal_nn_change(struct sock *sk, u8 feat, u64 nn_val) +{ + struct list_head *fn = &dccp_sk(sk)->dccps_featneg; + dccp_feat_val fval = { .nn = nn_val }; + struct dccp_feat_entry *entry; + + if (sk->sk_state != DCCP_OPEN && sk->sk_state != DCCP_PARTOPEN) + return 0; + + if (dccp_feat_type(feat) != FEAT_NN || + !dccp_feat_is_valid_nn_val(feat, nn_val)) return -EINVAL; - return __feat_register_nn(&dccp_sk(sk)->dccps_featneg, feat, 0, val); + + if (nn_val == dccp_feat_nn_get(sk, feat)) + return 0; /* already set or negotiation under way */ + + entry = dccp_feat_list_lookup(fn, feat, 1); + if (entry != NULL) { + dccp_pr_debug("Clobbering existing NN entry %llu -> %llu\n", + (unsigned long long)entry->val.nn, + (unsigned long long)nn_val); + dccp_feat_list_pop(entry); + } + + inet_csk_schedule_ack(sk); + return dccp_feat_push_change(fn, feat, 1, 0, &fval); } +EXPORT_SYMBOL_GPL(dccp_feat_signal_nn_change); /* * Tracking features whose value depend on the choice of CCID @@ -735,6 +936,7 @@ static const struct ccid_dependency *dccp_feat_ccid_deps(u8 ccid, bool is_local) * @fn: feature-negotiation list to update * @id: CCID number to track * @is_local: whether TX CCID (1) or RX CCID (0) is meant + * * This function needs to be called after registering all other features. */ static int dccp_feat_propagate_ccid(struct list_head *fn, u8 id, bool is_local) @@ -758,6 +960,7 @@ static int dccp_feat_propagate_ccid(struct list_head *fn, u8 id, bool is_local) /** * dccp_feat_finalise_settings - Finalise settings before starting negotiation * @dp: client or listening socket (settings will be inherited) + * * This is called after all registrations (socket initialisation, sysctls, and * sockopt calls), and before sending the first packet containing Change options * (ie. client-Request or server-Response), to ensure internal consistency. @@ -783,6 +986,7 @@ int dccp_feat_finalise_settings(struct dccp_sock *dp) while (i--) if (ccids[i] > 0 && dccp_feat_propagate_ccid(fn, ccids[i], i)) return -1; + dccp_feat_print_fnlist(fn); return 0; } @@ -901,6 +1105,8 @@ static u8 dccp_feat_change_recv(struct list_head *fn, u8 is_mandatory, u8 opt, if (len == 0 || type == FEAT_UNKNOWN) /* 6.1 and 6.6.8 */ goto unknown_feature_or_value; + dccp_feat_print_opt(opt, feat, val, len, is_mandatory); + /* * Negotiation of NN features: Change R is invalid, so there is no * simultaneous negotiation; hence we do not look up in the list. @@ -957,7 +1163,7 @@ static u8 dccp_feat_change_recv(struct list_head *fn, u8 is_mandatory, u8 opt, } if (dccp_feat_reconcile(&entry->val, val, len, server, true)) { - entry->empty_confirm = 0; + entry->empty_confirm = false; } else if (is_mandatory) { return DCCP_RESET_CODE_MANDATORY_ERROR; } else if (entry->state == FEAT_INITIALISING) { @@ -973,10 +1179,10 @@ static u8 dccp_feat_change_recv(struct list_head *fn, u8 is_mandatory, u8 opt, defval = dccp_feat_default_value(feat); if (!dccp_feat_reconcile(&entry->val, &defval, 1, server, true)) return DCCP_RESET_CODE_OPTION_ERROR; - entry->empty_confirm = 1; + entry->empty_confirm = true; } - entry->needs_confirm = 1; - entry->needs_mandatory = 0; + entry->needs_confirm = true; + entry->needs_mandatory = false; entry->state = FEAT_STABLE; return 0; @@ -1006,6 +1212,8 @@ static u8 dccp_feat_confirm_recv(struct list_head *fn, u8 is_mandatory, u8 opt, const bool local = (opt == DCCPO_CONFIRM_R); struct dccp_feat_entry *entry = dccp_feat_list_lookup(fn, feat, local); + dccp_feat_print_opt(opt, feat, val, len, is_mandatory); + if (entry == NULL) { /* nothing queued: ignore or handle error */ if (is_mandatory && type == FEAT_UNKNOWN) return DCCP_RESET_CODE_MANDATORY_ERROR; @@ -1077,6 +1285,101 @@ confirmation_failed: } /** + * dccp_feat_handle_nn_established - Fast-path reception of NN options + * @sk: socket of an established DCCP connection + * @mandatory: whether @opt was preceded by a Mandatory option + * @opt: %DCCPO_CHANGE_L | %DCCPO_CONFIRM_R (NN only) + * @feat: NN number, one of %dccp_feature_numbers + * @val: NN value + * @len: length of @val in bytes + * + * This function combines the functionality of change_recv/confirm_recv, with + * the following differences (reset codes are the same): + * - cleanup after receiving the Confirm; + * - values are directly activated after successful parsing; + * - deliberately restricted to NN features. + * The restriction to NN features is essential since SP features can have non- + * predictable outcomes (depending on the remote configuration), and are inter- + * dependent (CCIDs for instance cause further dependencies). + */ +static u8 dccp_feat_handle_nn_established(struct sock *sk, u8 mandatory, u8 opt, + u8 feat, u8 *val, u8 len) +{ + struct list_head *fn = &dccp_sk(sk)->dccps_featneg; + const bool local = (opt == DCCPO_CONFIRM_R); + struct dccp_feat_entry *entry; + u8 type = dccp_feat_type(feat); + dccp_feat_val fval; + + dccp_feat_print_opt(opt, feat, val, len, mandatory); + + /* Ignore non-mandatory unknown and non-NN features */ + if (type == FEAT_UNKNOWN) { + if (local && !mandatory) + return 0; + goto fast_path_unknown; + } else if (type != FEAT_NN) { + return 0; + } + + /* + * We don't accept empty Confirms, since in fast-path feature + * negotiation the values are enabled immediately after sending + * the Change option. + * Empty Changes on the other hand are invalid (RFC 4340, 6.1). + */ + if (len == 0 || len > sizeof(fval.nn)) + goto fast_path_unknown; + + if (opt == DCCPO_CHANGE_L) { + fval.nn = dccp_decode_value_var(val, len); + if (!dccp_feat_is_valid_nn_val(feat, fval.nn)) + goto fast_path_unknown; + + if (dccp_feat_push_confirm(fn, feat, local, &fval) || + dccp_feat_activate(sk, feat, local, &fval)) + return DCCP_RESET_CODE_TOO_BUSY; + + /* set the `Ack Pending' flag to piggyback a Confirm */ + inet_csk_schedule_ack(sk); + + } else if (opt == DCCPO_CONFIRM_R) { + entry = dccp_feat_list_lookup(fn, feat, local); + if (entry == NULL || entry->state != FEAT_CHANGING) + return 0; + + fval.nn = dccp_decode_value_var(val, len); + /* + * Just ignore a value that doesn't match our current value. + * If the option changes twice within two RTTs, then at least + * one CONFIRM will be received for the old value after a + * new CHANGE was sent. + */ + if (fval.nn != entry->val.nn) + return 0; + + /* Only activate after receiving the Confirm option (6.6.1). */ + dccp_feat_activate(sk, feat, local, &fval); + + /* It has been confirmed - so remove the entry */ + dccp_feat_list_pop(entry); + + } else { + DCCP_WARN("Received illegal option %u\n", opt); + goto fast_path_failed; + } + return 0; + +fast_path_unknown: + if (!mandatory) + return dccp_push_empty_confirm(fn, feat, local); + +fast_path_failed: + return mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR + : DCCP_RESET_CODE_OPTION_ERROR; +} + +/** * dccp_feat_parse_options - Process Feature-Negotiation Options * @sk: for general use and used by the client during connection setup * @dreq: used by the server during connection setup @@ -1085,6 +1388,7 @@ confirmation_failed: * @feat: one of %dccp_feature_numbers * @val: value contents of @opt * @len: length of @val in bytes + * * Returns 0 on success, a Reset code for ending the connection otherwise. */ int dccp_feat_parse_options(struct sock *sk, struct dccp_request_sock *dreq, @@ -1111,27 +1415,82 @@ int dccp_feat_parse_options(struct sock *sk, struct dccp_request_sock *dreq, return dccp_feat_confirm_recv(fn, mandatory, opt, feat, val, len, server); } + break; + /* + * Support for exchanging NN options on an established connection. + */ + case DCCP_OPEN: + case DCCP_PARTOPEN: + return dccp_feat_handle_nn_established(sk, mandatory, opt, feat, + val, len); } return 0; /* ignore FN options in all other states */ } +/** + * dccp_feat_init - Seed feature negotiation with host-specific defaults + * This initialises global defaults, depending on the value of the sysctls. + * These can later be overridden by registering changes via setsockopt calls. + * The last link in the chain is finalise_settings, to make sure that between + * here and the start of actual feature negotiation no inconsistencies enter. + * + * All features not appearing below use either defaults or are otherwise + * later adjusted through dccp_feat_finalise_settings(). + */ int dccp_feat_init(struct sock *sk) { - struct dccp_sock *dp = dccp_sk(sk); - struct dccp_minisock *dmsk = dccp_msk(sk); + struct list_head *fn = &dccp_sk(sk)->dccps_featneg; + u8 on = 1, off = 0; int rc; + struct { + u8 *val; + u8 len; + } tx, rx; + + /* Non-negotiable (NN) features */ + rc = __feat_register_nn(fn, DCCPF_SEQUENCE_WINDOW, 0, + sysctl_dccp_sequence_window); + if (rc) + return rc; + + /* Server-priority (SP) features */ + + /* Advertise that short seqnos are not supported (7.6.1) */ + rc = __feat_register_sp(fn, DCCPF_SHORT_SEQNOS, true, true, &off, 1); + if (rc) + return rc; + + /* RFC 4340 12.1: "If a DCCP is not ECN capable, ..." */ + rc = __feat_register_sp(fn, DCCPF_ECN_INCAPABLE, true, true, &on, 1); + if (rc) + return rc; + + /* + * We advertise the available list of CCIDs and reorder according to + * preferences, to avoid failure resulting from negotiating different + * singleton values (which always leads to failure). + * These settings can still (later) be overridden via sockopts. + */ + if (ccid_get_builtin_ccids(&tx.val, &tx.len) || + ccid_get_builtin_ccids(&rx.val, &rx.len)) + return -ENOBUFS; + + if (!dccp_feat_prefer(sysctl_dccp_tx_ccid, tx.val, tx.len) || + !dccp_feat_prefer(sysctl_dccp_rx_ccid, rx.val, rx.len)) + goto free_ccid_lists; + + rc = __feat_register_sp(fn, DCCPF_CCID, true, false, tx.val, tx.len); + if (rc) + goto free_ccid_lists; - INIT_LIST_HEAD(&dmsk->dccpms_pending); /* XXX no longer used */ - INIT_LIST_HEAD(&dmsk->dccpms_conf); /* XXX no longer used */ + rc = __feat_register_sp(fn, DCCPF_CCID, false, false, rx.val, rx.len); - /* Ack ratio */ - rc = __feat_register_nn(&dp->dccps_featneg, DCCPF_ACK_RATIO, 0, - dp->dccps_l_ack_ratio); +free_ccid_lists: + kfree(tx.val); + kfree(rx.val); return rc; } -EXPORT_SYMBOL_GPL(dccp_feat_init); - int dccp_feat_activate_values(struct sock *sk, struct list_head *fn_list) { struct dccp_sock *dp = dccp_sk(sk); @@ -1156,9 +1515,10 @@ int dccp_feat_activate_values(struct sock *sk, struct list_head *fn_list) goto activation_failed; } if (cur->state != FEAT_STABLE) { - DCCP_CRIT("Negotiation of %s %u failed in state %u", + DCCP_CRIT("Negotiation of %s %s failed in state %s", cur->is_local ? "local" : "remote", - cur->feat_num, cur->state); + dccp_feat_fname(cur->feat_num), + dccp_feat_sname[cur->state]); goto activation_failed; } fvals[idx][cur->is_local] = &cur->val; @@ -1199,43 +1559,3 @@ activation_failed: dp->dccps_hc_rx_ackvec = NULL; return -1; } - -#ifdef CONFIG_IP_DCCP_DEBUG -const char *dccp_feat_typename(const u8 type) -{ - switch(type) { - case DCCPO_CHANGE_L: return("ChangeL"); - case DCCPO_CONFIRM_L: return("ConfirmL"); - case DCCPO_CHANGE_R: return("ChangeR"); - case DCCPO_CONFIRM_R: return("ConfirmR"); - /* the following case must not appear in feature negotation */ - default: dccp_pr_debug("unknown type %d [BUG!]\n", type); - } - return NULL; -} - -const char *dccp_feat_name(const u8 feat) -{ - static const char *feature_names[] = { - [DCCPF_RESERVED] = "Reserved", - [DCCPF_CCID] = "CCID", - [DCCPF_SHORT_SEQNOS] = "Allow Short Seqnos", - [DCCPF_SEQUENCE_WINDOW] = "Sequence Window", - [DCCPF_ECN_INCAPABLE] = "ECN Incapable", - [DCCPF_ACK_RATIO] = "Ack Ratio", - [DCCPF_SEND_ACK_VECTOR] = "Send ACK Vector", - [DCCPF_SEND_NDP_COUNT] = "Send NDP Count", - [DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage", - [DCCPF_DATA_CHECKSUM] = "Send Data Checksum", - }; - if (feat > DCCPF_DATA_CHECKSUM && feat < DCCPF_MIN_CCID_SPECIFIC) - return feature_names[DCCPF_RESERVED]; - - if (feat == DCCPF_SEND_LEV_RATE) - return "Send Loss Event Rate"; - if (feat >= DCCPF_MIN_CCID_SPECIFIC) - return "CCID-specific"; - - return feature_names[feat]; -} -#endif /* CONFIG_IP_DCCP_DEBUG */ |
