commit 2884639ad63583d2a5a3dd14185c77212e566b5f Author: Nick Mathewson <nickm@torproject.org> Date: Wed Aug 1 08:47:27 2018 -0400 Extract tor_ersatz_socketpair into a new c file I'm doing this because I want to make it a lower-level function again, so that we can use it without linking in the rest of the universe. --- src/lib/net/include.am | 4 +- src/lib/net/socket.c | 155 +------------------------------------------- src/lib/net/socket.h | 8 --- src/lib/net/socketpair.c | 164 +++++++++++++++++++++++++++++++++++++++++++++++ src/lib/net/socketpair.h | 19 ++++++ src/test/test_util.c | 1 + 6 files changed, 188 insertions(+), 163 deletions(-) diff --git a/src/lib/net/include.am b/src/lib/net/include.am index 67db0d5af..ff0967e78 100644 --- a/src/lib/net/include.am +++ b/src/lib/net/include.am @@ -12,7 +12,8 @@ src_lib_libtor_net_a_SOURCES = \ src/lib/net/gethostname.c \ src/lib/net/inaddr.c \ src/lib/net/resolve.c \ - src/lib/net/socket.c + src/lib/net/socket.c \ + src/lib/net/socketpair.c src_lib_libtor_net_testing_a_SOURCES = \ $(src_lib_libtor_net_a_SOURCES) @@ -29,4 +30,5 @@ noinst_HEADERS += \ src/lib/net/nettypes.h \ src/lib/net/resolve.h \ src/lib/net/socket.h \ + src/lib/net/socketpair.h \ src/lib/net/socks5_status.h diff --git a/src/lib/net/socket.c b/src/lib/net/socket.c index 5847bb873..5487b8d9d 100644 --- a/src/lib/net/socket.c +++ b/src/lib/net/socket.c @@ -11,6 +11,7 @@ #define SOCKET_PRIVATE #include "lib/net/socket.h" +#include "lib/net/socketpair.h" #include "lib/net/address.h" #include "lib/cc/compat_compiler.h" #include "lib/err/torerr.h" @@ -476,160 +477,6 @@ tor_socketpair(int family, int type, int protocol, tor_socket_t fd[2]) #endif /* defined(HAVE_SOCKETPAIR) && !defined(_WIN32) */ } -#ifdef NEED_ERSATZ_SOCKETPAIR - -static inline socklen_t -SIZEOF_SOCKADDR(int domain) -{ - switch (domain) { - case AF_INET: - return sizeof(struct sockaddr_in); - case AF_INET6: - return sizeof(struct sockaddr_in6); - default: - return 0; - } -} - -/** - * Helper used to implement socketpair on systems that lack it, by - * making a direct connection to localhost. - */ -STATIC int -tor_ersatz_socketpair(int family, int type, int protocol, tor_socket_t fd[2]) -{ - /* This socketpair does not work when localhost is down. So - * it's really not the same thing at all. But it's close enough - * for now, and really, when localhost is down sometimes, we - * have other problems too. - */ - tor_socket_t listener = TOR_INVALID_SOCKET; - tor_socket_t connector = TOR_INVALID_SOCKET; - tor_socket_t acceptor = TOR_INVALID_SOCKET; - tor_addr_t listen_tor_addr; - struct sockaddr_storage connect_addr_ss, listen_addr_ss; - struct sockaddr *listen_addr = (struct sockaddr *) &listen_addr_ss; - uint16_t listen_port = 0; - tor_addr_t connect_tor_addr; - uint16_t connect_port = 0; - struct sockaddr *connect_addr = (struct sockaddr *) &connect_addr_ss; - socklen_t size; - int saved_errno = -1; - int ersatz_domain = AF_INET; - - memset(&connect_tor_addr, 0, sizeof(connect_tor_addr)); - memset(&connect_addr_ss, 0, sizeof(connect_addr_ss)); - memset(&listen_tor_addr, 0, sizeof(listen_tor_addr)); - memset(&listen_addr_ss, 0, sizeof(listen_addr_ss)); - - if (protocol -#ifdef AF_UNIX - || family != AF_UNIX -#endif - ) { -#ifdef _WIN32 - return -WSAEAFNOSUPPORT; -#else - return -EAFNOSUPPORT; -#endif - } - if (!fd) { - return -EINVAL; - } - - listener = tor_open_socket(ersatz_domain, type, 0); - if (!SOCKET_OK(listener)) { - int first_errno = tor_socket_errno(-1); - if (first_errno == SOCK_ERRNO(EPROTONOSUPPORT) - && ersatz_domain == AF_INET) { - /* Assume we're on an IPv6-only system */ - ersatz_domain = AF_INET6; - listener = tor_open_socket(ersatz_domain, type, 0); - if (!SOCKET_OK(listener)) { - /* Keep the previous behaviour, which was to return the IPv4 error. - * (This may be less informative on IPv6-only systems.) - * XX/teor - is there a better way to decide which errno to return? - * (I doubt we care much either way, once there is an error.) - */ - return -first_errno; - } - } - } - /* If there is no 127.0.0.1 or ::1, this will and must fail. Otherwise, we - * risk exposing a socketpair on a routable IP address. (Some BSD jails - * use a routable address for localhost. Fortunately, they have the real - * AF_UNIX socketpair.) */ - if (ersatz_domain == AF_INET) { - tor_addr_from_ipv4h(&listen_tor_addr, INADDR_LOOPBACK); - } else { - tor_addr_parse(&listen_tor_addr, "[::1]"); - } - tor_assert(tor_addr_is_loopback(&listen_tor_addr)); - size = tor_addr_to_sockaddr(&listen_tor_addr, - 0 /* kernel chooses port. */, - listen_addr, - sizeof(listen_addr_ss)); - if (bind(listener, listen_addr, size) == -1) - goto tidy_up_and_fail; - if (listen(listener, 1) == -1) - goto tidy_up_and_fail; - - connector = tor_open_socket(ersatz_domain, type, 0); - if (!SOCKET_OK(connector)) - goto tidy_up_and_fail; - /* We want to find out the port number to connect to. */ - size = sizeof(connect_addr_ss); - if (getsockname(listener, connect_addr, &size) == -1) - goto tidy_up_and_fail; - if (size != SIZEOF_SOCKADDR (connect_addr->sa_family)) - goto abort_tidy_up_and_fail; - if (connect(connector, connect_addr, size) == -1) - goto tidy_up_and_fail; - - size = sizeof(listen_addr_ss); - acceptor = tor_accept_socket(listener, listen_addr, &size); - if (!SOCKET_OK(acceptor)) - goto tidy_up_and_fail; - if (size != SIZEOF_SOCKADDR(listen_addr->sa_family)) - goto abort_tidy_up_and_fail; - /* Now check we are talking to ourself by matching port and host on the - two sockets. */ - if (getsockname(connector, connect_addr, &size) == -1) - goto tidy_up_and_fail; - /* Set *_tor_addr and *_port to the address and port that was used */ - tor_addr_from_sockaddr(&listen_tor_addr, listen_addr, &listen_port); - tor_addr_from_sockaddr(&connect_tor_addr, connect_addr, &connect_port); - if (size != SIZEOF_SOCKADDR (connect_addr->sa_family) - || tor_addr_compare(&listen_tor_addr, &connect_tor_addr, CMP_SEMANTIC) - || listen_port != connect_port) { - goto abort_tidy_up_and_fail; - } - tor_close_socket(listener); - fd[0] = connector; - fd[1] = acceptor; - - return 0; - - abort_tidy_up_and_fail: -#ifdef _WIN32 - saved_errno = WSAECONNABORTED; -#else - saved_errno = ECONNABORTED; /* I hope this is portable and appropriate. */ -#endif - tidy_up_and_fail: - if (saved_errno < 0) - saved_errno = errno; - if (SOCKET_OK(listener)) - tor_close_socket(listener); - if (SOCKET_OK(connector)) - tor_close_socket(connector); - if (SOCKET_OK(acceptor)) - tor_close_socket(acceptor); - return -saved_errno; -} - -#endif /* defined(NEED_ERSATZ_SOCKETPAIR) */ - /** Mockable wrapper for getsockname(). */ MOCK_IMPL(int, tor_getsockname,(tor_socket_t sock, struct sockaddr *address, diff --git a/src/lib/net/socket.h b/src/lib/net/socket.h index e2092c727..5b7d6dbbc 100644 --- a/src/lib/net/socket.h +++ b/src/lib/net/socket.h @@ -110,14 +110,6 @@ const char *tor_socket_strerror(int e); #define tor_socket_strerror(e) strerror(e) #endif /* defined(_WIN32) */ -#ifdef SOCKET_PRIVATE -#if !defined(HAVE_SOCKETPAIR) || defined(_WIN32) || defined(TOR_UNIT_TESTS) -#define NEED_ERSATZ_SOCKETPAIR -STATIC int tor_ersatz_socketpair(int family, int type, int protocol, - tor_socket_t fd[2]); -#endif -#endif /* defined(COMPAT_PRIVATE) */ - #if defined(_WIN32) && !defined(SIO_IDEAL_SEND_BACKLOG_QUERY) #define SIO_IDEAL_SEND_BACKLOG_QUERY 0x4004747b #endif diff --git a/src/lib/net/socketpair.c b/src/lib/net/socketpair.c new file mode 100644 index 000000000..945bdee69 --- /dev/null +++ b/src/lib/net/socketpair.c @@ -0,0 +1,164 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ + +#include "lib/net/socketpair.h" +#include "lib/net/socket.h" +#include "lib/net/address.h" + +#include <errno.h> +#include <string.h> + +#ifdef NEED_ERSATZ_SOCKETPAIR + +static inline socklen_t +SIZEOF_SOCKADDR(int domain) +{ + switch (domain) { + case AF_INET: + return sizeof(struct sockaddr_in); + case AF_INET6: + return sizeof(struct sockaddr_in6); + default: + return 0; + } +} + +/** + * Helper used to implement socketpair on systems that lack it, by + * making a direct connection to localhost. + */ +STATIC int +tor_ersatz_socketpair(int family, int type, int protocol, tor_socket_t fd[2]) +{ + /* This socketpair does not work when localhost is down. So + * it's really not the same thing at all. But it's close enough + * for now, and really, when localhost is down sometimes, we + * have other problems too. + */ + tor_socket_t listener = TOR_INVALID_SOCKET; + tor_socket_t connector = TOR_INVALID_SOCKET; + tor_socket_t acceptor = TOR_INVALID_SOCKET; + tor_addr_t listen_tor_addr; + struct sockaddr_storage connect_addr_ss, listen_addr_ss; + struct sockaddr *listen_addr = (struct sockaddr *) &listen_addr_ss; + uint16_t listen_port = 0; + tor_addr_t connect_tor_addr; + uint16_t connect_port = 0; + struct sockaddr *connect_addr = (struct sockaddr *) &connect_addr_ss; + socklen_t size; + int saved_errno = -1; + int ersatz_domain = AF_INET; + + memset(&connect_tor_addr, 0, sizeof(connect_tor_addr)); + memset(&connect_addr_ss, 0, sizeof(connect_addr_ss)); + memset(&listen_tor_addr, 0, sizeof(listen_tor_addr)); + memset(&listen_addr_ss, 0, sizeof(listen_addr_ss)); + + if (protocol +#ifdef AF_UNIX + || family != AF_UNIX +#endif + ) { +#ifdef _WIN32 + return -WSAEAFNOSUPPORT; +#else + return -EAFNOSUPPORT; +#endif + } + if (!fd) { + return -EINVAL; + } + + listener = tor_open_socket(ersatz_domain, type, 0); + if (!SOCKET_OK(listener)) { + int first_errno = tor_socket_errno(-1); + if (first_errno == SOCK_ERRNO(EPROTONOSUPPORT) + && ersatz_domain == AF_INET) { + /* Assume we're on an IPv6-only system */ + ersatz_domain = AF_INET6; + listener = tor_open_socket(ersatz_domain, type, 0); + if (!SOCKET_OK(listener)) { + /* Keep the previous behaviour, which was to return the IPv4 error. + * (This may be less informative on IPv6-only systems.) + * XX/teor - is there a better way to decide which errno to return? + * (I doubt we care much either way, once there is an error.) + */ + return -first_errno; + } + } + } + /* If there is no 127.0.0.1 or ::1, this will and must fail. Otherwise, we + * risk exposing a socketpair on a routable IP address. (Some BSD jails + * use a routable address for localhost. Fortunately, they have the real + * AF_UNIX socketpair.) */ + if (ersatz_domain == AF_INET) { + tor_addr_from_ipv4h(&listen_tor_addr, INADDR_LOOPBACK); + } else { + tor_addr_parse(&listen_tor_addr, "[::1]"); + } + tor_assert(tor_addr_is_loopback(&listen_tor_addr)); + size = tor_addr_to_sockaddr(&listen_tor_addr, + 0 /* kernel chooses port. */, + listen_addr, + sizeof(listen_addr_ss)); + if (bind(listener, listen_addr, size) == -1) + goto tidy_up_and_fail; + if (listen(listener, 1) == -1) + goto tidy_up_and_fail; + + connector = tor_open_socket(ersatz_domain, type, 0); + if (!SOCKET_OK(connector)) + goto tidy_up_and_fail; + /* We want to find out the port number to connect to. */ + size = sizeof(connect_addr_ss); + if (getsockname(listener, connect_addr, &size) == -1) + goto tidy_up_and_fail; + if (size != SIZEOF_SOCKADDR (connect_addr->sa_family)) + goto abort_tidy_up_and_fail; + if (connect(connector, connect_addr, size) == -1) + goto tidy_up_and_fail; + + size = sizeof(listen_addr_ss); + acceptor = tor_accept_socket(listener, listen_addr, &size); + if (!SOCKET_OK(acceptor)) + goto tidy_up_and_fail; + if (size != SIZEOF_SOCKADDR(listen_addr->sa_family)) + goto abort_tidy_up_and_fail; + /* Now check we are talking to ourself by matching port and host on the + two sockets. */ + if (getsockname(connector, connect_addr, &size) == -1) + goto tidy_up_and_fail; + /* Set *_tor_addr and *_port to the address and port that was used */ + tor_addr_from_sockaddr(&listen_tor_addr, listen_addr, &listen_port); + tor_addr_from_sockaddr(&connect_tor_addr, connect_addr, &connect_port); + if (size != SIZEOF_SOCKADDR (connect_addr->sa_family) + || tor_addr_compare(&listen_tor_addr, &connect_tor_addr, CMP_SEMANTIC) + || listen_port != connect_port) { + goto abort_tidy_up_and_fail; + } + tor_close_socket(listener); + fd[0] = connector; + fd[1] = acceptor; + + return 0; + + abort_tidy_up_and_fail: +#ifdef _WIN32 + saved_errno = WSAECONNABORTED; +#else + saved_errno = ECONNABORTED; /* I hope this is portable and appropriate. */ +#endif + tidy_up_and_fail: + if (saved_errno < 0) + saved_errno = errno; + if (SOCKET_OK(listener)) + tor_close_socket(listener); + if (SOCKET_OK(connector)) + tor_close_socket(connector); + if (SOCKET_OK(acceptor)) + tor_close_socket(acceptor); + return -saved_errno; +} + +#endif /* defined(NEED_ERSATZ_SOCKETPAIR) */ diff --git a/src/lib/net/socketpair.h b/src/lib/net/socketpair.h new file mode 100644 index 000000000..3efa65a67 --- /dev/null +++ b/src/lib/net/socketpair.h @@ -0,0 +1,19 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_SOCKETPAIR_H +#define TOR_SOCKETPAIR_H + +#include "orconfig.h" +#include "lib/testsupport/testsupport.h" +#include "lib/net/nettypes.h" + +#if !defined(HAVE_SOCKETPAIR) || defined(_WIN32) || defined(TOR_UNIT_TESTS) +#define NEED_ERSATZ_SOCKETPAIR +STATIC int tor_ersatz_socketpair(int family, int type, int protocol, + tor_socket_t fd[2]); +#endif + +#endif diff --git a/src/test/test_util.c b/src/test/test_util.c index 99fee4c5a..7afe83c69 100644 --- a/src/test/test_util.c +++ b/src/test/test_util.c @@ -38,6 +38,7 @@ #include "lib/meminfo/meminfo.h" #include "lib/time/tvdiff.h" #include "lib/encoding/confline.h" +#include "lib/net/socketpair.h" #ifdef HAVE_PWD_H #include <pwd.h>