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| | /* SPDX-License-Identifier: GPL-2.0-or-later
* Copyright Red Hat
* Author: David Gibson <david@gibson.dropbear.id.au>
*
* Definitions for the global table of packet flows.
*/
#ifndef FLOW_TABLE_H
#define FLOW_TABLE_H
#include "tcp_conn.h"
#include "icmp_flow.h"
#include "udp_flow.h"
/**
* struct flow_free_cluster - Information about a cluster of free entries
* @f: Generic flow information
* @n: Number of entries in the free cluster (including this one)
* @next: Index of next free cluster
*/
struct flow_free_cluster {
/* Must be first element */
struct flow_common f;
unsigned n;
unsigned next;
};
/**
* union flow - Descriptor for a logical packet flow (e.g. connection)
* @f: Fields common between all variants
* @tcp: Fields for non-spliced TCP connections
* @tcp_splice: Fields for spliced TCP connections
*/
union flow {
struct flow_common f;
struct flow_free_cluster free;
struct tcp_tap_conn tcp;
struct tcp_splice_conn tcp_splice;
struct icmp_ping_flow ping;
struct udp_flow udp;
};
/* Global Flow Table */
extern unsigned flow_first_free;
extern union flow flowtab[];
/** flow_idx - Index of flow from common structure
* @f: Common flow fields pointer
*
* Return: index of @f in the flow table
*/
static inline unsigned flow_idx(const struct flow_common *f)
{
return (union flow *)f - flowtab;
}
/** FLOW_IDX - Find the index of a flow
* @f_: Flow pointer, either union flow * or protocol specific
*
* Return: index of @f in the flow table
*/
#define FLOW_IDX(f_) (flow_idx(&(f_)->f))
/** FLOW - Flow entry at a given index
* @idx: Flow index
*
* Return: pointer to entry @idx in the flow table
*/
#define FLOW(idx) (&flowtab[(idx)])
/** flow_at_sidx - Flow entry for a given sidx
* @sidx: Flow & side index
*
* Return: pointer to the corresponding flow entry, or NULL
*/
static inline union flow *flow_at_sidx(flow_sidx_t sidx)
{
if (!flow_sidx_valid(sidx))
return NULL;
return FLOW(sidx.flow);
}
/** flow_sidx_opposite - Get the other side of the same flow
* @sidx: Flow & side index
*
* Return: sidx for the other side of the same flow as @sidx
*/
static inline flow_sidx_t flow_sidx_opposite(flow_sidx_t sidx)
{
if (!flow_sidx_valid(sidx))
return FLOW_SIDX_NONE;
return (flow_sidx_t){.flow = sidx.flow, .side = !sidx.side};
}
/** pif_at_sidx - Interface for a given flow and side
* @sidx: Flow & side index
*
* Return: pif for the flow & side given by @sidx
*/
static inline uint8_t pif_at_sidx(flow_sidx_t sidx)
{
const union flow *flow = flow_at_sidx(sidx);
if (!flow)
return PIF_NONE;
return flow->f.pif[sidx.side];
}
/** flowside_at_sidx - Retrieve a specific flowside
* @sidx: Flow & side index
*
* Return: Flowside for the flow & side given by @sidx
*/
static inline const struct flowside *flowside_at_sidx(flow_sidx_t sidx)
{
const union flow *flow = flow_at_sidx(sidx);
if (!flow)
return PIF_NONE;
return &flow->f.side[sidx.side];
}
/** flow_sidx_t - Index of one side of a flow from common structure
* @f: Common flow fields pointer
* @side: Which side to refer to (0 or 1)
*
* Return: index of @f and @side in the flow table
*/
static inline flow_sidx_t flow_sidx(const struct flow_common *f,
int side)
{
/* cppcheck-suppress [knownConditionTrueFalse, unmatchedSuppression] */
ASSERT(side == !!side);
return (flow_sidx_t){
.side = side,
.flow = flow_idx(f),
};
}
/** FLOW_SIDX - Find the index of one side of a flow
* @f_: Flow pointer, either union flow * or protocol specific
* @side: Which side to index (0 or 1)
*
* Return: index of @f and @side in the flow table
*/
#define FLOW_SIDX(f_, side) (flow_sidx(&(f_)->f, (side)))
union flow *flow_alloc(void);
void flow_alloc_cancel(union flow *flow);
const struct flowside *flow_initiate_af(union flow *flow, uint8_t pif,
sa_family_t af,
const void *saddr, in_port_t sport,
const void *daddr, in_port_t dport);
const struct flowside *flow_initiate_sa(union flow *flow, uint8_t pif,
const union sockaddr_inany *ssa,
in_port_t dport);
const struct flowside *flow_target_af(union flow *flow, uint8_t pif,
sa_family_t af,
const void *saddr, in_port_t sport,
const void *daddr, in_port_t dport);
const struct flowside *flow_target(const struct ctx *c, union flow *flow,
uint8_t proto);
union flow *flow_set_type(union flow *flow, enum flow_type type);
#define FLOW_SET_TYPE(flow_, t_, var_) (&flow_set_type((flow_), (t_))->var_)
void flow_activate(struct flow_common *f);
#define FLOW_ACTIVATE(flow_) \
(flow_activate(&(flow_)->f))
#endif /* FLOW_TABLE_H */
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