diff options
| -rw-r--r-- | net/dccp/feat.c | 14 | ||||
| -rw-r--r-- | net/dccp/feat.h | 60 |
2 files changed, 74 insertions, 0 deletions
diff --git a/net/dccp/feat.c b/net/dccp/feat.c index 933a0ecf8d4..94a81b8e5ef 100644 --- a/net/dccp/feat.c +++ b/net/dccp/feat.c @@ -23,6 +23,20 @@ #define DCCP_FEAT_SP_NOAGREE (-123) +/* copy constructor, fval must not already contain allocated memory */ +static int dccp_feat_clone_sp_val(dccp_feat_val *fval, u8 const *val, u8 len) +{ + fval->sp.len = len; + if (fval->sp.len > 0) { + fval->sp.vec = kmemdup(val, len, gfp_any()); + if (fval->sp.vec == NULL) { + fval->sp.len = 0; + return -ENOBUFS; + } + } + return 0; +} + int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature, u8 *val, u8 len, gfp_t gfp) { diff --git a/net/dccp/feat.h b/net/dccp/feat.h index e272222c7ac..94203c230c6 100644 --- a/net/dccp/feat.h +++ b/net/dccp/feat.h @@ -14,6 +14,66 @@ #include <linux/types.h> #include "dccp.h" +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 */ +}; + +/** + * 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) +{ + if (entry->needs_confirm) + return entry->is_local ? DCCPO_CONFIRM_L : DCCPO_CONFIRM_R; + return entry->is_local ? DCCPO_CHANGE_L : DCCPO_CHANGE_R; +} + #ifdef CONFIG_IP_DCCP_DEBUG extern const char *dccp_feat_typename(const u8 type); extern const char *dccp_feat_name(const u8 feat); |