/*
- * Copyright (C) 2011 - David Goulet <dgoulet@efficios.com>
+ * Copyright (C) 2011 David Goulet <dgoulet@efficios.com>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2 only,
- * as published by the Free Software Foundation.
+ * SPDX-License-Identifier: GPL-2.0-only
*
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef _COMPAT_SOCKET_H
#include <sys/socket.h>
#include <sys/un.h>
+#include <unistd.h>
#include <common/macros.h>
-#ifdef __linux__
-
-#define LTTNG_SOCK_CREDS SCM_CREDENTIALS
-
-typedef struct ucred lttng_sock_cred;
+#ifndef MSG_NOSIGNAL
+# ifdef SO_NOSIGPIPE
+# define MSG_NOSIGNAL SO_NOSIGPIPE
+# endif
+#endif
-#define LTTNG_SOCK_SET_UID_CRED(c, u) LTTNG_REF(c)->uid = u
-#define LTTNG_SOCK_SET_GID_CRED(c, g) LTTNG_REF(c)->gid = g
-#define LTTNG_SOCK_SET_PID_CRED(c, p) LTTNG_REF(c)->pid = p
+#if defined(MSG_NOSIGNAL)
+static inline
+ssize_t lttng_recvmsg_nosigpipe(int sockfd, struct msghdr *msg)
+{
+ return recvmsg(sockfd, msg, MSG_NOSIGNAL);
+}
+#else
-#define LTTNG_SOCK_GET_UID_CRED(c) LTTNG_REF(c)->uid
-#define LTTNG_SOCK_GET_GID_CRED(c) LTTNG_REF(c)->gid
-#define LTTNG_SOCK_GET_PID_CRED(c) LTTNG_REF(c)->pid
+#include <signal.h>
+#include <common/compat/errno.h>
-#elif (defined(__FreeBSD__) || defined(__CYGWIN__) || defined(__sun__))
+static inline
+ssize_t lttng_recvmsg_nosigpipe(int sockfd, struct msghdr *msg)
+{
+ ssize_t received;
+ int saved_err;
+ sigset_t sigpipe_set, pending_set, old_set;
+ int sigpipe_was_pending;
-struct lttng_sock_cred {
- uid_t uid;
- gid_t gid;
-};
+ /*
+ * Discard the SIGPIPE from send(), not disturbing any SIGPIPE
+ * that might be already pending. If a bogus SIGPIPE is sent to
+ * the entire process concurrently by a malicious user, it may
+ * be simply discarded.
+ */
+ if (sigemptyset(&pending_set)) {
+ return -1;
+ }
+ /*
+ * sigpending returns the mask of signals that are _both_
+ * blocked for the thread _and_ pending for either the thread or
+ * the entire process.
+ */
+ if (sigpending(&pending_set)) {
+ return -1;
+ }
+ sigpipe_was_pending = sigismember(&pending_set, SIGPIPE);
+ /*
+ * If sigpipe was pending, it means it was already blocked, so
+ * no need to block it.
+ */
+ if (!sigpipe_was_pending) {
+ if (sigemptyset(&sigpipe_set)) {
+ return -1;
+ }
+ if (sigaddset(&sigpipe_set, SIGPIPE)) {
+ return -1;
+ }
+ if (pthread_sigmask(SIG_BLOCK, &sigpipe_set, &old_set)) {
+ return -1;
+ }
+ }
-typedef struct lttng_sock_cred lttng_sock_cred;
+ /* Send and save errno. */
+ received = recvmsg(sockfd, msg, 0);
+ saved_err = errno;
-#define LTTNG_SOCK_GET_UID_CRED(c) LTTNG_REF(c)->uid
-#define LTTNG_SOCK_GET_GID_CRED(c) LTTNG_REF(c)->gid
-#define LTTNG_SOCK_GET_PID_CRED(c) -1
+ if (received == -1 && errno == EPIPE && !sigpipe_was_pending) {
+ struct timespec timeout = { 0, 0 };
+ int ret;
-#else
-#error "Please add support for your OS."
-#endif /* __linux__ , __FreeBSD__ */
+ do {
+ ret = sigtimedwait(&sigpipe_set, NULL,
+ &timeout);
+ } while (ret == -1 && errno == EINTR);
+ }
+ if (!sigpipe_was_pending) {
+ if (pthread_sigmask(SIG_SETMASK, &old_set, NULL)) {
+ return -1;
+ }
+ }
+ /* Restore send() errno */
+ errno = saved_err;
+ return received;
+}
+#endif
#ifdef __sun__
# endif
# endif
-
#include <ucred.h>
static inline
goto free;
}
*gid = ret;
+
ret = 0;
free:
ucred_free(ucred);
end:
return ret;
}
-
#endif /* __sun__ */
+
+#if defined(__linux__) || defined(__CYGWIN__)
+
+#define LTTNG_SOCK_CREDS SCM_CREDENTIALS
+
+typedef struct ucred lttng_sock_cred;
+
+#define LTTNG_SOCK_SET_UID_CRED(c, u) LTTNG_REF(c)->uid = u
+#define LTTNG_SOCK_SET_GID_CRED(c, g) LTTNG_REF(c)->gid = g
+#define LTTNG_SOCK_SET_PID_CRED(c, p) LTTNG_REF(c)->pid = p
+
+#define LTTNG_SOCK_GET_UID_CRED(c) LTTNG_REF(c)->uid
+#define LTTNG_SOCK_GET_GID_CRED(c) LTTNG_REF(c)->gid
+#define LTTNG_SOCK_GET_PID_CRED(c) LTTNG_REF(c)->pid
+
+#elif (defined(__FreeBSD__) || defined(__sun__) || defined(__APPLE__))
+
+struct lttng_sock_cred {
+ uid_t uid;
+ gid_t gid;
+ pid_t pid;
+};
+
+typedef struct lttng_sock_cred lttng_sock_cred;
+
+#define LTTNG_SOCK_SET_UID_CRED(c, u) LTTNG_REF(c)->uid = u
+#define LTTNG_SOCK_SET_GID_CRED(c, g) LTTNG_REF(c)->gid = g
+#define LTTNG_SOCK_SET_PID_CRED(c, p) LTTNG_REF(c)->pid = p
+
+#define LTTNG_SOCK_GET_UID_CRED(c) LTTNG_REF(c)->uid
+#define LTTNG_SOCK_GET_GID_CRED(c) LTTNG_REF(c)->gid
+#define LTTNG_SOCK_GET_PID_CRED(c) LTTNG_REF(c)->pid
+
+#ifdef __APPLE__
+
+static inline
+int lttng_get_unix_socket_peer_pid(int socket_fd, pid_t *pid)
+{
+ /* The getsockopt LOCAL_PEERPID option is available since macOS 10.8. */
+ return getsockopt(socket_fd, SOL_LOCAL, LOCAL_PEERPID, pid,
+ &((socklen_t) {sizeof(*pid)}));
+}
+
+#elif defined(__sun__)
+
+/* Use the getpeerucreds interface on Solaris. */
+static inline
+int lttng_get_unix_socket_peer_pid(int socket_fd, pid_t *pid)
+{
+ int ret = 0;
+ ucred_t *ucred = NULL;
+
+ ret = getpeerucred(s, &ucred);
+ if (ret == -1) {
+ goto end;
+ }
+
+ ret = ucred_getpid(ucred);
+ if (ret == -1) {
+ goto free;
+ }
+
+ *pid = ret;
+ ret = 0;
+free:
+ ucred_free(ucred);
+end:
+ return ret;
+}
+
+#elif defined(__FreeBSD__)
+
+#include <sys/ucred.h>
+
+static inline
+int lttng_get_unix_socket_peer_pid(int socket_fd, pid_t *pid)
+{
+ int ret;
+ struct xucred sock_creds = {};
+
+ /* Only available in FreeBSD 13.0 and up. */
+ ret = getsockopt(socket_fd, SOL_LOCAL, LOCAL_PEERCRED, &sock_creds,
+ &((socklen_t) {sizeof(sock_creds)}));
+ if (ret) {
+ goto end;
+ }
+
+ *pid = sock_creds.cr_pid;
+end:
+ return ret;
+}
+
+#endif /* __APPLE__ */
+
+
+static inline
+int lttng_get_unix_socket_peer_creds(int socket_fd, struct lttng_sock_cred *creds)
+{
+ int ret;
+
+ /* This is a BSD extension that is supported by Cygwin. */
+ ret = getpeereid(socket_fd, &creds->uid, &creds->gid);
+ if (ret) {
+ goto end;
+ }
+
+ /*
+ * Getting a peer's PID is a bit more troublesome as it is platform
+ * specific.
+ */
+ ret = lttng_get_unix_socket_peer_pid(socket_fd, &creds->pid);
+end:
+ return ret;
+}
+
+#else
+#error "Please add support for your OS."
+#endif /* __linux__ , __FreeBSD__, __APPLE__ */
+
#endif /* _COMPAT_SOCKET_H */