diff options
Diffstat (limited to 'src/common/compat.c')
| -rw-r--r-- | src/common/compat.c | 88 |
1 files changed, 64 insertions, 24 deletions
diff --git a/src/common/compat.c b/src/common/compat.c index 7d72b4b7fd..bd59e0f5a5 100644 --- a/src/common/compat.c +++ b/src/common/compat.c @@ -1486,6 +1486,12 @@ tor_socketpair(int family, int type, int protocol, tor_socket_t fd[2]) } #ifdef NEED_ERSATZ_SOCKETPAIR + +#define SIZEOF_SOCKADDR(domain) \ + (domain == AF_INET ? sizeof(struct sockaddr_in) : \ + (domain == AF_INET6 ? sizeof(struct sockaddr_in6) : \ + ((size_t)0) /* unsupported, don't match any valid size */)) + /** * Helper used to implement socketpair on systems that lack it, by * making a direct connection to localhost. @@ -1501,12 +1507,19 @@ tor_ersatz_socketpair(int family, int type, int protocol, tor_socket_t fd[2]) tor_socket_t listener = TOR_INVALID_SOCKET; tor_socket_t connector = TOR_INVALID_SOCKET; tor_socket_t acceptor = TOR_INVALID_SOCKET; - struct sockaddr_in listen_addr; - struct sockaddr_in connect_addr; + tor_addr_t listen_tor_addr; + struct sockaddr listen_addr; + in_port_t listen_port = 0; + tor_addr_t connect_tor_addr; + in_port_t connect_port = 0; + struct sockaddr connect_addr; socklen_t size; int saved_errno = -1; + int ersatz_domain = AF_INET; + memset(&connect_tor_addr, 0, sizeof(connect_tor_addr)); memset(&connect_addr, 0, sizeof(connect_addr)); + memset(&listen_tor_addr, 0, sizeof(listen_tor_addr)); memset(&listen_addr, 0, sizeof(listen_addr)); if (protocol @@ -1524,47 +1537,71 @@ tor_ersatz_socketpair(int family, int type, int protocol, tor_socket_t fd[2]) return -EINVAL; } - listener = tor_open_socket(AF_INET, type, 0); - if (!SOCKET_OK(listener)) - return -tor_socket_errno(-1); - memset(&listen_addr, 0, sizeof(listen_addr)); - listen_addr.sin_family = AF_INET; - listen_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); - listen_addr.sin_port = 0; /* kernel chooses port. */ - if (bind(listener, (struct sockaddr *) &listen_addr, sizeof (listen_addr)) - == -1) + 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)); + tor_addr_to_sockaddr(&listen_tor_addr, + 0 /* kernel chooses port. */, + &listen_addr, + sizeof(listen_addr)); + if (bind(listener, &listen_addr, sizeof (listen_addr)) == -1) goto tidy_up_and_fail; if (listen(listener, 1) == -1) goto tidy_up_and_fail; - connector = tor_open_socket(AF_INET, type, 0); + 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); - if (getsockname(listener, (struct sockaddr *) &connect_addr, &size) == -1) + if (getsockname(listener, &connect_addr, &size) == -1) goto tidy_up_and_fail; - if (size != sizeof (connect_addr)) + if (size != SIZEOF_SOCKADDR (connect_addr.sa_family)) goto abort_tidy_up_and_fail; - if (connect(connector, (struct sockaddr *) &connect_addr, - sizeof(connect_addr)) == -1) + if (connect(connector, &connect_addr, sizeof(connect_addr)) == -1) goto tidy_up_and_fail; size = sizeof(listen_addr); - acceptor = tor_accept_socket(listener, - (struct sockaddr *) &listen_addr, &size); + acceptor = tor_accept_socket(listener, &listen_addr, &size); if (!SOCKET_OK(acceptor)) goto tidy_up_and_fail; - if (size != sizeof(listen_addr)) + 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, (struct sockaddr *) &connect_addr, &size) == -1) + if (getsockname(connector, &connect_addr, &size) == -1) goto tidy_up_and_fail; - if (size != sizeof (connect_addr) - || listen_addr.sin_family != connect_addr.sin_family - || listen_addr.sin_addr.s_addr != connect_addr.sin_addr.s_addr - || listen_addr.sin_port != connect_addr.sin_port) { + /* 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); @@ -1590,6 +1627,9 @@ tor_ersatz_socketpair(int family, int type, int protocol, tor_socket_t fd[2]) tor_close_socket(acceptor); return -saved_errno; } + +#undef SIZEOF_SOCKADDR + #endif /* Return the maximum number of allowed sockets. */ |