curl/lib/socketpair.c
Daniel Stenberg c074ba64a8
code: language cleanup in comments
Based on the standards and guidelines we use for our documentation.

 - expand contractions (they're => they are etc)
 - host name = > hostname
 - file name => filename
 - user name = username
 - man page => manpage
 - run-time => runtime
 - set-up => setup
 - back-end => backend
 - a HTTP => an HTTP
 - Two spaces after a period => one space after period

Closes #14073
2024-07-01 22:58:55 +02:00

265 lines
6.8 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
#include "curl_setup.h"
#include "socketpair.h"
#include "urldata.h"
#include "rand.h"
#if defined(USE_EVENTFD)
#ifdef HAVE_SYS_EVENTFD_H
#include <sys/eventfd.h>
#endif
int Curl_eventfd(curl_socket_t socks[2], bool nonblocking)
{
int efd = eventfd(0, nonblocking ? EFD_CLOEXEC | EFD_NONBLOCK : EFD_CLOEXEC);
if(efd == -1) {
socks[0] = socks[1] = CURL_SOCKET_BAD;
return -1;
}
socks[0] = socks[1] = efd;
return 0;
}
#elif defined(HAVE_PIPE)
#ifdef HAVE_FCNTL
#include <fcntl.h>
#endif
int Curl_pipe(curl_socket_t socks[2], bool nonblocking)
{
if(pipe(socks))
return -1;
#ifdef HAVE_FCNTL
if(fcntl(socks[0], F_SETFD, FD_CLOEXEC) ||
fcntl(socks[1], F_SETFD, FD_CLOEXEC) ) {
close(socks[0]);
close(socks[1]);
socks[0] = socks[1] = CURL_SOCKET_BAD;
return -1;
}
#endif
if(nonblocking) {
if(curlx_nonblock(socks[0], TRUE) < 0 ||
curlx_nonblock(socks[1], TRUE) < 0) {
close(socks[0]);
close(socks[1]);
socks[0] = socks[1] = CURL_SOCKET_BAD;
return -1;
}
}
return 0;
}
#endif
#ifndef CURL_DISABLE_SOCKETPAIR
#ifdef HAVE_SOCKETPAIR
int Curl_socketpair(int domain, int type, int protocol,
curl_socket_t socks[2], bool nonblocking)
{
#ifdef SOCK_NONBLOCK
type = nonblocking ? type | SOCK_NONBLOCK : type;
#endif
if(socketpair(domain, type, protocol, socks))
return -1;
#ifndef SOCK_NONBLOCK
if(nonblocking) {
if(curlx_nonblock(socks[0], TRUE) < 0 ||
curlx_nonblock(socks[1], TRUE) < 0) {
close(socks[0]);
close(socks[1]);
return -1;
}
}
#endif
return 0;
}
#else /* !HAVE_SOCKETPAIR */
#ifdef _WIN32
/*
* This is a socketpair() implementation for Windows.
*/
#include <string.h>
#include <io.h>
#else
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h> /* IPPROTO_TCP */
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifndef INADDR_LOOPBACK
#define INADDR_LOOPBACK 0x7f000001
#endif /* !INADDR_LOOPBACK */
#endif /* !_WIN32 */
#include "nonblock.h" /* for curlx_nonblock */
#include "timeval.h" /* needed before select.h */
#include "select.h" /* for Curl_poll */
/* The last 3 #include files should be in this order */
#include "curl_printf.h"
#include "curl_memory.h"
#include "memdebug.h"
int Curl_socketpair(int domain, int type, int protocol,
curl_socket_t socks[2], bool nonblocking)
{
union {
struct sockaddr_in inaddr;
struct sockaddr addr;
} a;
curl_socket_t listener;
curl_socklen_t addrlen = sizeof(a.inaddr);
int reuse = 1;
struct pollfd pfd[1];
(void)domain;
(void)type;
(void)protocol;
listener = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if(listener == CURL_SOCKET_BAD)
return -1;
memset(&a, 0, sizeof(a));
a.inaddr.sin_family = AF_INET;
a.inaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
a.inaddr.sin_port = 0;
socks[0] = socks[1] = CURL_SOCKET_BAD;
#if defined(_WIN32) || defined(__CYGWIN__)
/* do not set SO_REUSEADDR on Windows */
(void)reuse;
#ifdef SO_EXCLUSIVEADDRUSE
{
int exclusive = 1;
if(setsockopt(listener, SOL_SOCKET, SO_EXCLUSIVEADDRUSE,
(char *)&exclusive, (curl_socklen_t)sizeof(exclusive)) == -1)
goto error;
}
#endif
#else
if(setsockopt(listener, SOL_SOCKET, SO_REUSEADDR,
(char *)&reuse, (curl_socklen_t)sizeof(reuse)) == -1)
goto error;
#endif
if(bind(listener, &a.addr, sizeof(a.inaddr)) == -1)
goto error;
if(getsockname(listener, &a.addr, &addrlen) == -1 ||
addrlen < (int)sizeof(a.inaddr))
goto error;
if(listen(listener, 1) == -1)
goto error;
socks[0] = socket(AF_INET, SOCK_STREAM, 0);
if(socks[0] == CURL_SOCKET_BAD)
goto error;
if(connect(socks[0], &a.addr, sizeof(a.inaddr)) == -1)
goto error;
/* use non-blocking accept to make sure we do not block forever */
if(curlx_nonblock(listener, TRUE) < 0)
goto error;
pfd[0].fd = listener;
pfd[0].events = POLLIN;
pfd[0].revents = 0;
(void)Curl_poll(pfd, 1, 1000); /* one second */
socks[1] = accept(listener, NULL, NULL);
if(socks[1] == CURL_SOCKET_BAD)
goto error;
else {
struct curltime start = Curl_now();
char rnd[9];
char check[sizeof(rnd)];
char *p = &check[0];
size_t s = sizeof(check);
if(Curl_rand(NULL, (unsigned char *)rnd, sizeof(rnd)))
goto error;
/* write data to the socket */
swrite(socks[0], rnd, sizeof(rnd));
/* verify that we read the correct data */
do {
ssize_t nread;
pfd[0].fd = socks[1];
pfd[0].events = POLLIN;
pfd[0].revents = 0;
(void)Curl_poll(pfd, 1, 1000); /* one second */
nread = sread(socks[1], p, s);
if(nread == -1) {
int sockerr = SOCKERRNO;
/* Do not block forever */
if(Curl_timediff(Curl_now(), start) > (60 * 1000))
goto error;
if(
#ifdef WSAEWOULDBLOCK
/* This is how Windows does it */
(WSAEWOULDBLOCK == sockerr)
#else
/* errno may be EWOULDBLOCK or on some systems EAGAIN when it
returned due to its inability to send off data without
blocking. We therefore treat both error codes the same here */
(EWOULDBLOCK == sockerr) || (EAGAIN == sockerr) ||
(EINTR == sockerr) || (EINPROGRESS == sockerr)
#endif
) {
continue;
}
goto error;
}
s -= nread;
if(s) {
p += nread;
continue;
}
if(memcmp(rnd, check, sizeof(check)))
goto error;
break;
} while(1);
}
if(nonblocking)
if(curlx_nonblock(socks[0], TRUE) < 0 ||
curlx_nonblock(socks[1], TRUE) < 0)
goto error;
sclose(listener);
return 0;
error:
sclose(listener);
sclose(socks[0]);
sclose(socks[1]);
return -1;
}
#endif
#endif /* !CURL_DISABLE_SOCKETPAIR */