osdep: implement qemu_socketpair() for win32
Manually implement a socketpair() function, using UNIX sockets and
simple peer credential checking.
QEMU doesn't make much use of socketpair, beside vhost-user which is not
available for win32 at this point. However, I intend to use it for
writing some new portable tests.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230306122751.2355515-5-marcandre.lureau@redhat.com>
diff --git a/include/qemu/sockets.h b/include/qemu/sockets.h
index 2b0698a..d935fd8 100644
--- a/include/qemu/sockets.h
+++ b/include/qemu/sockets.h
@@ -15,7 +15,6 @@
bool fd_is_socket(int fd);
int qemu_socket(int domain, int type, int protocol);
-#ifndef WIN32
/**
* qemu_socketpair:
* @domain: specifies a communication domain, such as PF_UNIX
@@ -30,7 +29,6 @@
* Return 0 on success.
*/
int qemu_socketpair(int domain, int type, int protocol, int sv[2]);
-#endif
int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen);
/*
diff --git a/util/oslib-win32.c b/util/oslib-win32.c
index 29a667a..16f8a67 100644
--- a/util/oslib-win32.c
+++ b/util/oslib-win32.c
@@ -310,6 +310,116 @@
return qemu_socket_select(sockfd, NULL, 0, errp);
}
+int qemu_socketpair(int domain, int type, int protocol, int sv[2])
+{
+ struct sockaddr_un addr = {
+ 0,
+ };
+ socklen_t socklen;
+ int listener = -1;
+ int client = -1;
+ int server = -1;
+ g_autofree char *path = NULL;
+ int tmpfd;
+ u_long arg;
+ int ret = -1;
+
+ g_return_val_if_fail(sv != NULL, -1);
+
+ addr.sun_family = AF_UNIX;
+ socklen = sizeof(addr);
+
+ tmpfd = g_file_open_tmp(NULL, &path, NULL);
+ if (tmpfd == -1 || !path) {
+ errno = EACCES;
+ goto out;
+ }
+
+ close(tmpfd);
+
+ if (strlen(path) >= sizeof(addr.sun_path)) {
+ errno = EINVAL;
+ goto out;
+ }
+
+ strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);
+
+ listener = socket(domain, type, protocol);
+ if (listener == -1) {
+ goto out;
+ }
+
+ if (DeleteFile(path) == 0 && GetLastError() != ERROR_FILE_NOT_FOUND) {
+ errno = EACCES;
+ goto out;
+ }
+ g_clear_pointer(&path, g_free);
+
+ if (bind(listener, (struct sockaddr *)&addr, socklen) == -1) {
+ goto out;
+ }
+
+ if (listen(listener, 1) == -1) {
+ goto out;
+ }
+
+ client = socket(domain, type, protocol);
+ if (client == -1) {
+ goto out;
+ }
+
+ arg = 1;
+ if (ioctlsocket(client, FIONBIO, &arg) != NO_ERROR) {
+ goto out;
+ }
+
+ if (connect(client, (struct sockaddr *)&addr, socklen) == -1 &&
+ WSAGetLastError() != WSAEWOULDBLOCK) {
+ goto out;
+ }
+
+ server = accept(listener, NULL, NULL);
+ if (server == -1) {
+ goto out;
+ }
+
+ arg = 0;
+ if (ioctlsocket(client, FIONBIO, &arg) != NO_ERROR) {
+ goto out;
+ }
+
+ arg = 0;
+ if (ioctlsocket(client, SIO_AF_UNIX_GETPEERPID, &arg) != NO_ERROR) {
+ goto out;
+ }
+
+ if (arg != GetCurrentProcessId()) {
+ errno = EPERM;
+ goto out;
+ }
+
+ sv[0] = server;
+ server = -1;
+ sv[1] = client;
+ client = -1;
+ ret = 0;
+
+out:
+ if (listener != -1) {
+ close(listener);
+ }
+ if (client != -1) {
+ close(client);
+ }
+ if (server != -1) {
+ close(server);
+ }
+ if (path) {
+ DeleteFile(path);
+ }
+ return ret;
+}
+
#undef connect
int qemu_connect_wrap(int sockfd, const struct sockaddr *addr,
socklen_t addrlen)
