diff options
Diffstat (limited to 'net/dccp/feat.h')
-rw-r--r-- | net/dccp/feat.h | 144 |
1 files changed, 24 insertions, 120 deletions
diff --git a/net/dccp/feat.h b/net/dccp/feat.h index 2217066e22d..e272222c7ac 100644 --- a/net/dccp/feat.h +++ b/net/dccp/feat.h @@ -3,134 +3,38 @@ /* * net/dccp/feat.h * - * Feature negotiation for the DCCP protocol (RFC 4340, section 6) - * Copyright (c) 2008 Gerrit Renker <gerrit@erg.abdn.ac.uk> + * An implementation of the DCCP protocol * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk> * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. */ + #include <linux/types.h> #include "dccp.h" -/* - * Known limit values - */ -/* Ack Ratio takes 2-byte integer values (11.3) */ -#define DCCPF_ACK_RATIO_MAX 0xFFFF -/* Wmin=32 and Wmax=2^46-1 from 7.5.2 */ -#define DCCPF_SEQ_WMIN 32 -#define DCCPF_SEQ_WMAX 0x3FFFFFFFFFFFull -/* Maximum number of SP values that fit in a single (Confirm) option */ -#define DCCP_FEAT_MAX_SP_VALS (DCCP_SINGLE_OPT_MAXLEN - 2) - -enum dccp_feat_type { - FEAT_AT_RX = 1, /* located at RX side of half-connection */ - FEAT_AT_TX = 2, /* located at TX side of half-connection */ - FEAT_SP = 4, /* server-priority reconciliation (6.3.1) */ - FEAT_NN = 8, /* non-negotiable reconciliation (6.3.2) */ - FEAT_UNKNOWN = 0xFF /* not understood or invalid feature */ -}; - -enum dccp_feat_state { - FEAT_DEFAULT = 0, /* using default values from 6.4 */ - FEAT_INITIALISING, /* feature is being initialised */ - FEAT_CHANGING, /* Change sent but not confirmed yet */ - FEAT_UNSTABLE, /* local modification in state CHANGING */ - FEAT_STABLE /* both ends (think they) agree */ -}; +#ifdef CONFIG_IP_DCCP_DEBUG +extern const char *dccp_feat_typename(const u8 type); +extern const char *dccp_feat_name(const u8 feat); -/** - * dccp_feat_val - Container for SP or NN feature values - * @nn: single NN value - * @sp.vec: single SP value plus optional preference list - * @sp.len: length of @sp.vec in bytes - */ -typedef union { - u64 nn; - struct { - u8 *vec; - u8 len; - } sp; -} dccp_feat_val; - -/** - * struct feat_entry - Data structure to perform feature negotiation - * @feat_num: one of %dccp_feature_numbers - * @val: feature's current value (SP features may have preference list) - * @state: feature's current state - * @needs_mandatory: whether Mandatory options should be sent - * @needs_confirm: whether to send a Confirm instead of a Change - * @empty_confirm: whether to send an empty Confirm (depends on @needs_confirm) - * @is_local: feature location (1) or feature-remote (0) - * @node: list pointers, entries arranged in FIFO order - */ -struct dccp_feat_entry { - u8 feat_num; - dccp_feat_val val; - enum dccp_feat_state state:8; - bool needs_mandatory:1, - needs_confirm:1, - empty_confirm:1, - is_local:1; - - struct list_head node; -}; - -static inline u8 dccp_feat_genopt(struct dccp_feat_entry *entry) +static inline void dccp_feat_debug(const u8 type, const u8 feat, const u8 val) { - if (entry->needs_confirm) - return entry->is_local ? DCCPO_CONFIRM_L : DCCPO_CONFIRM_R; - return entry->is_local ? DCCPO_CHANGE_L : DCCPO_CHANGE_R; + dccp_pr_debug("%s(%s (%d), %d)\n", dccp_feat_typename(type), + dccp_feat_name(feat), feat, val); } +#else +#define dccp_feat_debug(type, feat, val) +#endif /* CONFIG_IP_DCCP_DEBUG */ + +extern int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature, + u8 *val, u8 len, gfp_t gfp); +extern int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature, + u8 *val, u8 len); +extern int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature, + u8 *val, u8 len); +extern void dccp_feat_clean(struct dccp_minisock *dmsk); +extern int dccp_feat_clone(struct sock *oldsk, struct sock *newsk); +extern int dccp_feat_init(struct dccp_minisock *dmsk); -/** - * struct ccid_dependency - Track changes resulting from choosing a CCID - * @dependent_feat: one of %dccp_feature_numbers - * @is_local: local (1) or remote (0) @dependent_feat - * @is_mandatory: whether presence of @dependent_feat is mission-critical or not - * @val: corresponding default value for @dependent_feat (u8 is sufficient here) - */ -struct ccid_dependency { - u8 dependent_feat; - bool is_local:1, - is_mandatory:1; - u8 val; -}; - -/* - * Sysctls to seed defaults for feature negotiation - */ -extern unsigned long sysctl_dccp_sequence_window; -extern int sysctl_dccp_rx_ccid; -extern int sysctl_dccp_tx_ccid; - -extern int dccp_feat_init(struct sock *sk); -extern void dccp_feat_initialise_sysctls(void); -extern int dccp_feat_register_sp(struct sock *sk, u8 feat, u8 is_local, - u8 const *list, u8 len); -extern int dccp_feat_register_nn(struct sock *sk, u8 feat, u64 val); -extern int dccp_feat_parse_options(struct sock *, struct dccp_request_sock *, - u8 mand, u8 opt, u8 feat, u8 *val, u8 len); -extern int dccp_feat_clone_list(struct list_head const *, struct list_head *); - -/* - * Encoding variable-length options and their maximum length. - * - * This affects NN options (SP options are all u8) and other variable-length - * options (see table 3 in RFC 4340). The limit is currently given the Sequence - * Window NN value (sec. 7.5.2) and the NDP count (sec. 7.7) option, all other - * options consume less than 6 bytes (timestamps are 4 bytes). - * When updating this constant (e.g. due to new internet drafts / RFCs), make - * sure that you also update all code which refers to it. - */ -#define DCCP_OPTVAL_MAXLEN 6 - -extern void dccp_encode_value_var(const u64 value, u8 *to, const u8 len); -extern u64 dccp_decode_value_var(const u8 *bf, const u8 len); - -extern int dccp_insert_option_mandatory(struct sk_buff *skb); -extern int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat, - u8 *val, u8 len, bool repeat_first); #endif /* _DCCP_FEAT_H */ |