Commit 383724e1 authored by Andrey Ignatov's avatar Andrey Ignatov Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add connect_fd_to_fd, connect_wait net helpers 



Add two new network helpers.

connect_fd_to_fd connects an already created client socket fd to address
of server fd. Sometimes it's useful to separate client socket creation
and connecting this socket to a server, e.g. if client socket has to be
created in a cgroup different from that of server cgroup.

Additionally connect_to_fd is now implemented using connect_fd_to_fd,
both helpers don't treat EINPROGRESS as an error and let caller decide
how to proceed with it.

connect_wait is a helper to work with non-blocking client sockets so
that if connect_to_fd or connect_fd_to_fd returned -1 with errno ==
EINPROGRESS, caller can wait for connect to finish or for connection
timeout. The helper returns -1 on error, 0 on timeout (1sec,
hard-coded), and positive number on success.

Signed-off-by: default avatarAndrey Ignatov <rdna@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarYonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/1403fab72300f379ca97ead4820ae43eac4414ef.1589486450.git.rdna@fb.com
parent f307fa2c

tools/testing/selftests/bpf/network_helpers.c

+61 −13
Original line number Diff line number Diff line
@@ -4,10 +4,14 @@ 
#include <stdio.h>

#include <string.h>

#include <unistd.h>



#include <sys/epoll.h>



#include <linux/err.h>

#include <linux/in.h>

#include <linux/in6.h>



#include "bpf_util.h"

#include "network_helpers.h"



#define clean_errno() (errno == 0 ? "None" : strerror(errno))
@@ -77,9 +81,7 @@ static const size_t timeo_optlen = sizeof(timeo_sec); 


int connect_to_fd(int family, int type, int server_fd)

{

	struct sockaddr_storage addr;

	socklen_t len = sizeof(addr);

	int fd;

	int fd, save_errno;



	fd = socket(family, type, 0);

	if (fd < 0) {
@@ -87,24 +89,70 @@ int connect_to_fd(int family, int type, int server_fd) 
		return -1;

	}



	if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeo_sec, timeo_optlen)) {

	if (connect_fd_to_fd(fd, server_fd) < 0 && errno != EINPROGRESS) {

		save_errno = errno;

		close(fd);

		errno = save_errno;

		return -1;

	}



	return fd;

}



int connect_fd_to_fd(int client_fd, int server_fd)

{

	struct sockaddr_storage addr;

	socklen_t len = sizeof(addr);

	int save_errno;



	if (setsockopt(client_fd, SOL_SOCKET, SO_RCVTIMEO, &timeo_sec,

		       timeo_optlen)) {

		log_err("Failed to set SO_RCVTIMEO");

		goto out;

		return -1;

	}



	if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {

		log_err("Failed to get server addr");

		goto out;

		return -1;

	}



	if (connect(fd, (const struct sockaddr *)&addr, len) < 0) {

		log_err("Fail to connect to server with family %d", family);

		goto out;

	if (connect(client_fd, (const struct sockaddr *)&addr, len) < 0) {

		if (errno != EINPROGRESS) {

			save_errno = errno;

			log_err("Failed to connect to server");

			errno = save_errno;

		}

		return -1;

	}



	return fd;

	return 0;

}



out:

	close(fd);

int connect_wait(int fd)

{

	struct epoll_event ev = {}, events[2];

	int timeout_ms = 1000;

	int efd, nfd;



	efd = epoll_create1(EPOLL_CLOEXEC);

	if (efd < 0) {

		log_err("Failed to open epoll fd");

		return -1;

	}



	ev.events = EPOLLRDHUP | EPOLLOUT;

	ev.data.fd = fd;



	if (epoll_ctl(efd, EPOLL_CTL_ADD, fd, &ev) < 0) {

		log_err("Failed to register fd=%d on epoll fd=%d", fd, efd);

		close(efd);

		return -1;

	}



	nfd = epoll_wait(efd, events, ARRAY_SIZE(events), timeout_ms);

	if (nfd < 0)

		log_err("Failed to wait for I/O event on epoll fd=%d", efd);



	close(efd);

	return nfd;

}

tools/testing/selftests/bpf/network_helpers.h

+2 −0
Original line number Diff line number Diff line
@@ -35,5 +35,7 @@ extern struct ipv6_packet pkt_v6; 


int start_server(int family, int type);

int connect_to_fd(int family, int type, int server_fd);

int connect_fd_to_fd(int client_fd, int server_fd);

int connect_wait(int client_fd);



#endif

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