mirrors/passt
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

tcp: Add struct for TCP execution context, move hash_secret to it

Browse source 
We don't need to keep small data as static variables, move the only
small variable we have so far to the new struct.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
Stefano Brivio 2021-03-17 10:57:41 +01:00
parent bb9fb9e2d1
commit cd14bff5ea
3 changed files with 36 additions and 17 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
passt.h
View file

@ -1,5 +1,7 @@
#define UNIX_SOCK_PATH "/tmp/passt.socket" #define UNIX_SOCK_PATH "/tmp/passt.socket"
#include "tcp.h"
/** /**
* struct ctx - Execution context * struct ctx - Execution context
* @epollfd: file descriptor for epoll instance * @epollfd: file descriptor for epoll instance
@ -36,4 +38,6 @@ struct ctx {
struct in6_addr dns6; struct in6_addr dns6;
char ifn[IF_NAMESIZE]; char ifn[IF_NAMESIZE];
struct tcp_ctx tcp;
}; };

34
tcp.c
View file

@ -453,9 +453,6 @@ static struct tcp_conn tc[MAX_CONNS];
/* Hash table for socket lookup given remote address, local port, remote port */ /* Hash table for socket lookup given remote address, local port, remote port */
static int tc_hash[TCP_HASH_TABLE_SIZE]; static int tc_hash[TCP_HASH_TABLE_SIZE];
/* 128-bit secret for hash functions, for initial sequence numbers and table */
static uint64_t hash_secret[2];
static int tcp_send_to_tap(struct ctx *c, int s, int flags, char *in, int len); static int tcp_send_to_tap(struct ctx *c, int s, int flags, char *in, int len);
/** /**
@ -574,6 +571,7 @@ static int tcp_sock_hash_match(struct tcp_conn *conn, int af, void *addr,
/** /**
* tcp_sock_hash() - Calculate hash value for connection given address and ports * tcp_sock_hash() - Calculate hash value for connection given address and ports
* @c: Execution context
* @af: Address family, AF_INET or AF_INET6 * @af: Address family, AF_INET or AF_INET6
* @addr: Remote address, pointer to sin_addr or sin6_addr * @addr: Remote address, pointer to sin_addr or sin6_addr
* @tap_port: tap-facing port * @tap_port: tap-facing port
@ -581,7 +579,7 @@ static int tcp_sock_hash_match(struct tcp_conn *conn, int af, void *addr,
* *
* Return: hash value, already modulo size of the hash table * Return: hash value, already modulo size of the hash table
*/ */
static unsigned int tcp_sock_hash(int af, void *addr, static unsigned int tcp_sock_hash(struct ctx *c, int af, void *addr,
in_port_t tap_port, in_port_t sock_port) in_port_t tap_port, in_port_t sock_port)
{ {
uint64_t b; uint64_t b;
@ -597,7 +595,7 @@ static unsigned int tcp_sock_hash(int af, void *addr,
.sock_port = sock_port, .sock_port = sock_port,
}; };
b = siphash_8b((uint8_t *)&in, hash_secret); b = siphash_8b((uint8_t *)&in, c->tcp.hash_secret);
} else if (af == AF_INET6) { } else if (af == AF_INET6) {
struct { struct {
struct in6_addr addr; struct in6_addr addr;
@ -609,7 +607,7 @@ static unsigned int tcp_sock_hash(int af, void *addr,
.sock_port = sock_port, .sock_port = sock_port,
}; };
b = siphash_20b((uint8_t *)&in, hash_secret); b = siphash_20b((uint8_t *)&in, c->tcp.hash_secret);
} }
return (unsigned int)(b % TCP_HASH_TABLE_SIZE); return (unsigned int)(b % TCP_HASH_TABLE_SIZE);
@ -617,18 +615,19 @@ static unsigned int tcp_sock_hash(int af, void *addr,
/** /**
* tcp_sock_hash_insert() - Insert socket into hash table, chain link if needed * tcp_sock_hash_insert() - Insert socket into hash table, chain link if needed
* @c: Execution context
* @s: File descriptor number for socket * @s: File descriptor number for socket
* @af: Address family, AF_INET or AF_INET6 * @af: Address family, AF_INET or AF_INET6
* @addr: Remote address, pointer to sin_addr or sin6_addr * @addr: Remote address, pointer to sin_addr or sin6_addr
* @tap_port: tap-facing port * @tap_port: tap-facing port
* @sock_port: Socket-facing port * @sock_port: Socket-facing port
*/ */
static void tcp_sock_hash_insert(int s, int af, void *addr, static void tcp_sock_hash_insert(struct ctx *c, int s, int af, void *addr,
in_port_t tap_port, in_port_t sock_port) in_port_t tap_port, in_port_t sock_port)
{ {
int b; int b;
b = tcp_sock_hash(af, addr, tap_port, sock_port); b = tcp_sock_hash(c, af, addr, tap_port, sock_port);
tc[s].next = tc_hash[b] ? &tc[tc_hash[b]] : NULL; tc[s].next = tc_hash[b] ? &tc[tc_hash[b]] : NULL;
tc_hash[b] = tc[s].sock = s; tc_hash[b] = tc[s].sock = s;
tc[s].hash_bucket = b; tc[s].hash_bucket = b;
@ -657,6 +656,7 @@ static void tcp_sock_hash_remove(int b, int s)
/** /**
* tcp_sock_hash_lookup() - Look up socket given remote address and ports * tcp_sock_hash_lookup() - Look up socket given remote address and ports
* @c: Execution context
* @af: Address family, AF_INET or AF_INET6 * @af: Address family, AF_INET or AF_INET6
* @addr: Remote address, pointer to sin_addr or sin6_addr * @addr: Remote address, pointer to sin_addr or sin6_addr
* @tap_port: tap-facing port * @tap_port: tap-facing port
@ -664,13 +664,13 @@ static void tcp_sock_hash_remove(int b, int s)
* *
* Return: file descriptor number for socket, if found, -ENOENT otherwise * Return: file descriptor number for socket, if found, -ENOENT otherwise
*/ */
static int tcp_sock_hash_lookup(int af, void *addr, static int tcp_sock_hash_lookup(struct ctx *c, int af, void *addr,
in_port_t tap_port, in_port_t sock_port) in_port_t tap_port, in_port_t sock_port)
{ {
struct tcp_conn *conn; struct tcp_conn *conn;
int b; int b;
b = tcp_sock_hash(af, addr, tap_port, sock_port); b = tcp_sock_hash(c, af, addr, tap_port, sock_port);
if (!tc_hash[b]) if (!tc_hash[b])
return -ENOENT; return -ENOENT;
@ -869,7 +869,7 @@ static uint32_t tcp_seq_init(struct ctx *c, int af, void *addr,
.dstport = dstport, .dstport = dstport,
}; };
seq = siphash_12b((uint8_t *)&in, hash_secret); seq = siphash_12b((uint8_t *)&in, c->tcp.hash_secret);
} else if (af == AF_INET6) { } else if (af == AF_INET6) {
struct { struct {
struct in6_addr src; struct in6_addr src;
@ -883,7 +883,7 @@ static uint32_t tcp_seq_init(struct ctx *c, int af, void *addr,
.dstport = dstport, .dstport = dstport,
}; };
seq = siphash_36b((uint8_t *)&in, hash_secret); seq = siphash_36b((uint8_t *)&in, c->tcp.hash_secret);
} }
ns = ts.tv_sec * 1E9; ns = ts.tv_sec * 1E9;
@ -963,7 +963,7 @@ static void tcp_conn_from_tap(struct ctx *c, int af, void *addr,
tc[s].seq_to_tap = tcp_seq_init(c, af, addr, th->dest, th->source); tc[s].seq_to_tap = tcp_seq_init(c, af, addr, th->dest, th->source);
tc[s].seq_ack_from_tap = tc[s].seq_to_tap + 1; tc[s].seq_ack_from_tap = tc[s].seq_to_tap + 1;
tcp_sock_hash_insert(s, af, addr, th->source, th->dest); tcp_sock_hash_insert(c, s, af, addr, th->source, th->dest);
if (connect(s, sa, sl)) { if (connect(s, sa, sl)) {
if (errno != EINPROGRESS) { if (errno != EINPROGRESS) {
@ -1016,7 +1016,7 @@ static void tcp_conn_from_sock(struct ctx *c, int fd)
tc[s].sock_port, tc[s].sock_port,
tc[s].tap_port); tc[s].tap_port);
tcp_sock_hash_insert(s, AF_INET, &sa4->sin_addr, tcp_sock_hash_insert(c, s, AF_INET, &sa4->sin_addr,
tc[s].tap_port, tc[s].sock_port); tc[s].tap_port, tc[s].sock_port);
} else if (sa_l.ss_family == AF_INET6) { } else if (sa_l.ss_family == AF_INET6) {
struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)&sa_r; struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)&sa_r;
@ -1030,7 +1030,7 @@ static void tcp_conn_from_sock(struct ctx *c, int fd)
tc[s].sock_port, tc[s].sock_port,
tc[s].tap_port); tc[s].tap_port);
tcp_sock_hash_insert(s, AF_INET6, &sa6->sin6_addr, tcp_sock_hash_insert(c, s, AF_INET6, &sa6->sin6_addr,
tc[s].tap_port, tc[s].sock_port); tc[s].tap_port, tc[s].sock_port);
} }
@ -1201,7 +1201,7 @@ void tcp_tap_handler(struct ctx *c, int af, void *addr, char *in, size_t len)
if (off < sizeof(*th) || off > len) if (off < sizeof(*th) || off > len)
return; return;
if ((s = tcp_sock_hash_lookup(af, addr, th->source, th->dest)) < 0) { if ((s = tcp_sock_hash_lookup(c, af, addr, th->source, th->dest)) < 0) {
if (th->syn) if (th->syn)
tcp_conn_from_tap(c, af, addr, th, len); tcp_conn_from_tap(c, af, addr, th, len);
return; return;
@ -1431,7 +1431,7 @@ int tcp_sock_init(struct ctx *c)
return -1; return -1;
} }
getrandom(hash_secret, sizeof(hash_secret), GRND_RANDOM); getrandom(&c->tcp.hash_secret, sizeof(c->tcp.hash_secret), GRND_RANDOM);
return 0; return 0;
} }

15
tcp.h
View file

@ -1,4 +1,19 @@
#ifndef TCP_H
#define TCP_H
struct ctx;
void tcp_sock_handler(struct ctx *c, int s, uint32_t events); void tcp_sock_handler(struct ctx *c, int s, uint32_t events);
void tcp_tap_handler(struct ctx *c, int af, void *addr, char *in, size_t len); void tcp_tap_handler(struct ctx *c, int af, void *addr, char *in, size_t len);
int tcp_sock_init(struct ctx *c); int tcp_sock_init(struct ctx *c);
void tcp_timer(struct ctx *c, struct timespec *ts); void tcp_timer(struct ctx *c, struct timespec *ts);
/**
* struct tcp_ctx - Execution context for TCP routines
* @hash_secret: 128-bit secret for hash functions, ISN and hash table
*/
struct tcp_ctx {
uint64_t hash_secret[2];
};
#endif /* TCP_H */