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| | /* SPDX-License-Identifier: GPL-2.0-or-later
* Copyright Red Hat
* Author: David Gibson <david@gibson.dropbear.id.au>
*
* Tracking for logical "flows" of packets.
*/
#ifndef FLOW_H
#define FLOW_H
#define FLOW_TIMER_INTERVAL 1000 /* ms */
/**
* enum flow_type - Different types of packet flows we track
*/
enum flow_type {
/* Represents an invalid or unused flow */
FLOW_TYPE_NONE = 0,
/* A TCP connection between a socket and tap interface */
FLOW_TCP,
/* A TCP connection between a host socket and ns socket */
FLOW_TCP_SPLICE,
/* ICMP echo requests from guest to host and matching replies back */
FLOW_PING4,
/* ICMPv6 echo requests from guest to host and matching replies back */
FLOW_PING6,
FLOW_NUM_TYPES,
};
extern const char *flow_type_str[];
#define FLOW_TYPE(f) \
((f)->type < FLOW_NUM_TYPES ? flow_type_str[(f)->type] : "?")
extern const uint8_t flow_proto[];
#define FLOW_PROTO(f) \
((f)->type < FLOW_NUM_TYPES ? flow_proto[(f)->type] : 0)
/**
* struct flowside - Common information for one side of a flow
* @eaddr: Endpoint address (remote address from passt's PoV)
* @faddr: Forwarding address (local address from passt's PoV)
* @eport: Endpoint port
* @fport: Forwarding port
* @pif: pif ID on which this side of the flow exists
*/
struct flowside {
union inany_addr faddr;
union inany_addr eaddr;
in_port_t fport;
in_port_t eport;
uint8_t pif;
};
static_assert(_Alignof(struct flowside) == _Alignof(uint32_t),
"Unexpected alignment for struct flowside");
/** flowside_from_inany - Initialize flowside from inany addresses
* @fside: flowside to initialize
* @pif: pif id of this flowside
* @faddr: Forwarding address (inany)
* @fport: Forwarding port
* @eaddr: Endpoint address (inany)
* @eport: Endpoint port
*/
/* cppcheck-suppress unusedFunction */
static inline void flowside_from_inany(struct flowside *fside, uint8_t pif,
const union inany_addr *faddr, in_port_t fport,
const union inany_addr *eaddr, in_port_t eport)
{
fside->pif = pif;
fside->faddr = *faddr;
fside->eaddr = *eaddr;
fside->fport = fport;
fside->eport = eport;
}
/** flowside_from_af - Initialize flowside from addresses
* @fside: flowside to initialize
* @pif: pif id of this flowside
* @af: Address family (AF_INET or AF_INET6)
* @faddr: Forwarding address (pointer to in_addr or in6_addr, or NULL)
* @fport: Forwarding port
* @eaddr: Endpoint address (pointer to in_addr or in6_addr, or NULL)
* @eport: Endpoint port
*
* If NULL is given for either address, the appropriate unspecified/any address
* for the address family is substituted.
*/
static inline void flowside_from_af(struct flowside *fside,
uint8_t pif, sa_family_t af,
const void *faddr, in_port_t fport,
const void *eaddr, in_port_t eport)
{
const union inany_addr *any = af == AF_INET ? &inany_any4 : &inany_any6;
fside->pif = pif;
if (faddr)
inany_from_af(&fside->faddr, af, faddr);
else
fside->faddr = *any;
if (eaddr)
inany_from_af(&fside->eaddr, af, eaddr);
else
fside->eaddr = *any;
fside->fport = fport;
fside->eport = eport;
}
#define SIDES 2
/**
* flowside_eq() - Check if two flowsides are equal
* @left, @right: Flowsides to compare
*
* Return: true if equal, false otherwise
*/
static inline bool flowside_eq(const struct flowside *left,
const struct flowside *right)
{
return left->pif == right->pif &&
inany_equals(&left->eaddr, &right->eaddr) &&
left->eport == right->eport &&
inany_equals(&left->faddr, &right->faddr) &&
left->fport == right->fport;
}
/**
* struct flow_common - Common fields for packet flows
* @side[]: Information for each side of the flow
* @type: Type of packet flow
*/
struct flow_common {
struct flowside side[SIDES];
uint8_t type;
};
#define FLOW_INDEX_BITS 17 /* 128k - 1 */
#define FLOW_MAX MAX_FROM_BITS(FLOW_INDEX_BITS)
#define FLOW_TABLE_PRESSURE 30 /* % of FLOW_MAX */
#define FLOW_FILE_PRESSURE 30 /* % of c->nofile */
union flow *flow_start(union flow *flow, enum flow_type type,
unsigned iniside);
#define FLOW_START(flow_, t_, var_, i_) \
(&flow_start((flow_), (t_), (i_))->var_)
/**
* struct flow_sidx - ID for one side of a specific flow
* @side: Side referenced (0 or 1)
* @flow: Index of flow referenced
*/
typedef struct flow_sidx {
unsigned side :1;
unsigned flow :FLOW_INDEX_BITS;
} flow_sidx_t;
static_assert(sizeof(flow_sidx_t) <= sizeof(uint32_t),
"flow_sidx_t must fit within 32 bits");
#define FLOW_SIDX_NONE ((flow_sidx_t){ .flow = FLOW_MAX })
/**
* flow_sidx_eq() - Test if two sidx values are equal
* @a, @b: sidx values
*
* Return: true iff @a and @b refer to the same side of the same flow
*/
static inline bool flow_sidx_eq(flow_sidx_t a, flow_sidx_t b)
{
return (a.flow == b.flow) && (a.side == b.side);
}
void flow_hash_insert(const struct ctx *c, flow_sidx_t sidx);
void flow_hash_remove(const struct ctx *c, flow_sidx_t sidx);
flow_sidx_t flow_hash_lookup(const struct ctx *c,
uint8_t proto, uint8_t pif, sa_family_t af,
const void *eaddr, const void *faddr,
in_port_t eport, in_port_t fport);
union flow;
void flow_init(void);
void flow_defer_handler(const struct ctx *c, const struct timespec *now);
void flow_log_(const struct flow_common *f, int pri, const char *fmt, ...)
__attribute__((format(printf, 3, 4)));
#define flow_log(f_, pri, ...) flow_log_(&(f_)->f, (pri), __VA_ARGS__)
#define flow_dbg(f, ...) flow_log((f), LOG_DEBUG, __VA_ARGS__)
#define flow_err(f, ...) flow_log((f), LOG_ERR, __VA_ARGS__)
#define flow_trace(f, ...) \
do { \
if (log_trace) \
flow_dbg((f), __VA_ARGS__); \
} while (0)
#endif /* FLOW_H */
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