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Diffstat (limited to 'src/grp-udev/libudev-core/udev-ctrl.c')
-rw-r--r--src/grp-udev/libudev-core/udev-ctrl.c462
1 files changed, 462 insertions, 0 deletions
diff --git a/src/grp-udev/libudev-core/udev-ctrl.c b/src/grp-udev/libudev-core/udev-ctrl.c
new file mode 100644
index 0000000000..f68a09d7a8
--- /dev/null
+++ b/src/grp-udev/libudev-core/udev-ctrl.c
@@ -0,0 +1,462 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008 Kay Sievers <kay@vrfy.org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ */
+
+#include <errno.h>
+#include <poll.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "formats-util.h"
+#include "socket-util.h"
+#include "udev.h"
+
+/* wire protocol magic must match */
+#define UDEV_CTRL_MAGIC 0xdead1dea
+
+enum udev_ctrl_msg_type {
+ UDEV_CTRL_UNKNOWN,
+ UDEV_CTRL_SET_LOG_LEVEL,
+ UDEV_CTRL_STOP_EXEC_QUEUE,
+ UDEV_CTRL_START_EXEC_QUEUE,
+ UDEV_CTRL_RELOAD,
+ UDEV_CTRL_SET_ENV,
+ UDEV_CTRL_SET_CHILDREN_MAX,
+ UDEV_CTRL_PING,
+ UDEV_CTRL_EXIT,
+};
+
+struct udev_ctrl_msg_wire {
+ char version[16];
+ unsigned int magic;
+ enum udev_ctrl_msg_type type;
+ union {
+ int intval;
+ char buf[256];
+ };
+};
+
+struct udev_ctrl_msg {
+ int refcount;
+ struct udev_ctrl_connection *conn;
+ struct udev_ctrl_msg_wire ctrl_msg_wire;
+};
+
+struct udev_ctrl {
+ int refcount;
+ struct udev *udev;
+ int sock;
+ union sockaddr_union saddr;
+ socklen_t addrlen;
+ bool bound;
+ bool cleanup_socket;
+ bool connected;
+};
+
+struct udev_ctrl_connection {
+ int refcount;
+ struct udev_ctrl *uctrl;
+ int sock;
+};
+
+struct udev_ctrl *udev_ctrl_new_from_fd(struct udev *udev, int fd) {
+ struct udev_ctrl *uctrl;
+ const int on = 1;
+ int r;
+
+ uctrl = new0(struct udev_ctrl, 1);
+ if (uctrl == NULL)
+ return NULL;
+ uctrl->refcount = 1;
+ uctrl->udev = udev;
+
+ if (fd < 0) {
+ uctrl->sock = socket(AF_LOCAL, SOCK_SEQPACKET|SOCK_NONBLOCK|SOCK_CLOEXEC, 0);
+ if (uctrl->sock < 0) {
+ log_error_errno(errno, "error getting socket: %m");
+ udev_ctrl_unref(uctrl);
+ return NULL;
+ }
+ } else {
+ uctrl->bound = true;
+ uctrl->sock = fd;
+ }
+
+ /*
+ * FIXME: remove it as soon as we can depend on this:
+ * http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=90c6bd34f884cd9cee21f1d152baf6c18bcac949
+ */
+ r = setsockopt(uctrl->sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on));
+ if (r < 0)
+ log_warning_errno(errno, "could not set SO_PASSCRED: %m");
+
+ uctrl->saddr.un.sun_family = AF_LOCAL;
+ strscpy(uctrl->saddr.un.sun_path, sizeof(uctrl->saddr.un.sun_path), "/run/udev/control");
+ uctrl->addrlen = SOCKADDR_UN_LEN(uctrl->saddr.un);
+ return uctrl;
+}
+
+struct udev_ctrl *udev_ctrl_new(struct udev *udev) {
+ return udev_ctrl_new_from_fd(udev, -1);
+}
+
+int udev_ctrl_enable_receiving(struct udev_ctrl *uctrl) {
+ int err;
+
+ if (!uctrl->bound) {
+ err = bind(uctrl->sock, &uctrl->saddr.sa, uctrl->addrlen);
+ if (err < 0 && errno == EADDRINUSE) {
+ unlink(uctrl->saddr.un.sun_path);
+ err = bind(uctrl->sock, &uctrl->saddr.sa, uctrl->addrlen);
+ }
+
+ if (err < 0)
+ return log_error_errno(errno, "bind failed: %m");
+
+ err = listen(uctrl->sock, 0);
+ if (err < 0)
+ return log_error_errno(errno, "listen failed: %m");
+
+ uctrl->bound = true;
+ uctrl->cleanup_socket = true;
+ }
+ return 0;
+}
+
+struct udev *udev_ctrl_get_udev(struct udev_ctrl *uctrl) {
+ return uctrl->udev;
+}
+
+static struct udev_ctrl *udev_ctrl_ref(struct udev_ctrl *uctrl) {
+ if (uctrl)
+ uctrl->refcount++;
+
+ return uctrl;
+}
+
+struct udev_ctrl *udev_ctrl_unref(struct udev_ctrl *uctrl) {
+ if (uctrl && -- uctrl->refcount == 0) {
+ if (uctrl->sock >= 0)
+ close(uctrl->sock);
+ free(uctrl);
+ }
+
+ return NULL;
+}
+
+int udev_ctrl_cleanup(struct udev_ctrl *uctrl) {
+ if (uctrl == NULL)
+ return 0;
+ if (uctrl->cleanup_socket)
+ unlink(uctrl->saddr.un.sun_path);
+ return 0;
+}
+
+int udev_ctrl_get_fd(struct udev_ctrl *uctrl) {
+ if (uctrl == NULL)
+ return -EINVAL;
+ return uctrl->sock;
+}
+
+struct udev_ctrl_connection *udev_ctrl_get_connection(struct udev_ctrl *uctrl) {
+ struct udev_ctrl_connection *conn;
+ struct ucred ucred = {};
+ const int on = 1;
+ int r;
+
+ conn = new(struct udev_ctrl_connection, 1);
+ if (conn == NULL)
+ return NULL;
+ conn->refcount = 1;
+ conn->uctrl = uctrl;
+
+ conn->sock = accept4(uctrl->sock, NULL, NULL, SOCK_CLOEXEC|SOCK_NONBLOCK);
+ if (conn->sock < 0) {
+ if (errno != EINTR)
+ log_error_errno(errno, "unable to receive ctrl connection: %m");
+ goto err;
+ }
+
+ /* check peer credential of connection */
+ r = getpeercred(conn->sock, &ucred);
+ if (r < 0) {
+ log_error_errno(r, "unable to receive credentials of ctrl connection: %m");
+ goto err;
+ }
+ if (ucred.uid > 0) {
+ log_error("sender uid="UID_FMT", message ignored", ucred.uid);
+ goto err;
+ }
+
+ /* enable receiving of the sender credentials in the messages */
+ r = setsockopt(conn->sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on));
+ if (r < 0)
+ log_warning_errno(errno, "could not set SO_PASSCRED: %m");
+
+ udev_ctrl_ref(uctrl);
+ return conn;
+err:
+ if (conn->sock >= 0)
+ close(conn->sock);
+ free(conn);
+ return NULL;
+}
+
+struct udev_ctrl_connection *udev_ctrl_connection_ref(struct udev_ctrl_connection *conn) {
+ if (conn == NULL)
+ return NULL;
+ conn->refcount++;
+ return conn;
+}
+
+struct udev_ctrl_connection *udev_ctrl_connection_unref(struct udev_ctrl_connection *conn) {
+ if (conn && -- conn->refcount == 0) {
+ if (conn->sock >= 0)
+ close(conn->sock);
+
+ udev_ctrl_unref(conn->uctrl);
+
+ free(conn);
+ }
+
+ return NULL;
+}
+
+static int ctrl_send(struct udev_ctrl *uctrl, enum udev_ctrl_msg_type type, int intval, const char *buf, int timeout) {
+ struct udev_ctrl_msg_wire ctrl_msg_wire;
+ int err = 0;
+
+ memzero(&ctrl_msg_wire, sizeof(struct udev_ctrl_msg_wire));
+ strcpy(ctrl_msg_wire.version, "udev-" VERSION);
+ ctrl_msg_wire.magic = UDEV_CTRL_MAGIC;
+ ctrl_msg_wire.type = type;
+
+ if (buf != NULL)
+ strscpy(ctrl_msg_wire.buf, sizeof(ctrl_msg_wire.buf), buf);
+ else
+ ctrl_msg_wire.intval = intval;
+
+ if (!uctrl->connected) {
+ if (connect(uctrl->sock, &uctrl->saddr.sa, uctrl->addrlen) < 0) {
+ err = -errno;
+ goto out;
+ }
+ uctrl->connected = true;
+ }
+ if (send(uctrl->sock, &ctrl_msg_wire, sizeof(ctrl_msg_wire), 0) < 0) {
+ err = -errno;
+ goto out;
+ }
+
+ /* wait for peer message handling or disconnect */
+ for (;;) {
+ struct pollfd pfd[1];
+ int r;
+
+ pfd[0].fd = uctrl->sock;
+ pfd[0].events = POLLIN;
+ r = poll(pfd, 1, timeout * MSEC_PER_SEC);
+ if (r < 0) {
+ if (errno == EINTR)
+ continue;
+ err = -errno;
+ break;
+ }
+
+ if (r > 0 && pfd[0].revents & POLLERR) {
+ err = -EIO;
+ break;
+ }
+
+ if (r == 0)
+ err = -ETIMEDOUT;
+ break;
+ }
+out:
+ return err;
+}
+
+int udev_ctrl_send_set_log_level(struct udev_ctrl *uctrl, int priority, int timeout) {
+ return ctrl_send(uctrl, UDEV_CTRL_SET_LOG_LEVEL, priority, NULL, timeout);
+}
+
+int udev_ctrl_send_stop_exec_queue(struct udev_ctrl *uctrl, int timeout) {
+ return ctrl_send(uctrl, UDEV_CTRL_STOP_EXEC_QUEUE, 0, NULL, timeout);
+}
+
+int udev_ctrl_send_start_exec_queue(struct udev_ctrl *uctrl, int timeout) {
+ return ctrl_send(uctrl, UDEV_CTRL_START_EXEC_QUEUE, 0, NULL, timeout);
+}
+
+int udev_ctrl_send_reload(struct udev_ctrl *uctrl, int timeout) {
+ return ctrl_send(uctrl, UDEV_CTRL_RELOAD, 0, NULL, timeout);
+}
+
+int udev_ctrl_send_set_env(struct udev_ctrl *uctrl, const char *key, int timeout) {
+ return ctrl_send(uctrl, UDEV_CTRL_SET_ENV, 0, key, timeout);
+}
+
+int udev_ctrl_send_set_children_max(struct udev_ctrl *uctrl, int count, int timeout) {
+ return ctrl_send(uctrl, UDEV_CTRL_SET_CHILDREN_MAX, count, NULL, timeout);
+}
+
+int udev_ctrl_send_ping(struct udev_ctrl *uctrl, int timeout) {
+ return ctrl_send(uctrl, UDEV_CTRL_PING, 0, NULL, timeout);
+}
+
+int udev_ctrl_send_exit(struct udev_ctrl *uctrl, int timeout) {
+ return ctrl_send(uctrl, UDEV_CTRL_EXIT, 0, NULL, timeout);
+}
+
+struct udev_ctrl_msg *udev_ctrl_receive_msg(struct udev_ctrl_connection *conn) {
+ struct udev_ctrl_msg *uctrl_msg;
+ ssize_t size;
+ struct cmsghdr *cmsg;
+ struct iovec iov;
+ char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
+ struct msghdr smsg = {
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ .msg_control = cred_msg,
+ .msg_controllen = sizeof(cred_msg),
+ };
+ struct ucred *cred;
+
+ uctrl_msg = new0(struct udev_ctrl_msg, 1);
+ if (uctrl_msg == NULL)
+ return NULL;
+ uctrl_msg->refcount = 1;
+ uctrl_msg->conn = conn;
+ udev_ctrl_connection_ref(conn);
+
+ /* wait for the incoming message */
+ for (;;) {
+ struct pollfd pfd[1];
+ int r;
+
+ pfd[0].fd = conn->sock;
+ pfd[0].events = POLLIN;
+
+ r = poll(pfd, 1, 10000);
+ if (r < 0) {
+ if (errno == EINTR)
+ continue;
+ goto err;
+ } else if (r == 0) {
+ log_error("timeout waiting for ctrl message");
+ goto err;
+ } else {
+ if (!(pfd[0].revents & POLLIN)) {
+ log_error_errno(errno, "ctrl connection error: %m");
+ goto err;
+ }
+ }
+
+ break;
+ }
+
+ iov.iov_base = &uctrl_msg->ctrl_msg_wire;
+ iov.iov_len = sizeof(struct udev_ctrl_msg_wire);
+
+ size = recvmsg(conn->sock, &smsg, 0);
+ if (size < 0) {
+ log_error_errno(errno, "unable to receive ctrl message: %m");
+ goto err;
+ }
+
+ cmsg_close_all(&smsg);
+
+ cmsg = CMSG_FIRSTHDR(&smsg);
+
+ if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
+ log_error("no sender credentials received, message ignored");
+ goto err;
+ }
+
+ cred = (struct ucred *) CMSG_DATA(cmsg);
+
+ if (cred->uid != 0) {
+ log_error("sender uid="UID_FMT", message ignored", cred->uid);
+ goto err;
+ }
+
+ if (uctrl_msg->ctrl_msg_wire.magic != UDEV_CTRL_MAGIC) {
+ log_error("message magic 0x%08x doesn't match, ignore it", uctrl_msg->ctrl_msg_wire.magic);
+ goto err;
+ }
+
+ return uctrl_msg;
+err:
+ udev_ctrl_msg_unref(uctrl_msg);
+ return NULL;
+}
+
+struct udev_ctrl_msg *udev_ctrl_msg_unref(struct udev_ctrl_msg *ctrl_msg) {
+ if (ctrl_msg && -- ctrl_msg->refcount == 0) {
+ udev_ctrl_connection_unref(ctrl_msg->conn);
+ free(ctrl_msg);
+ }
+
+ return NULL;
+}
+
+int udev_ctrl_get_set_log_level(struct udev_ctrl_msg *ctrl_msg) {
+ if (ctrl_msg->ctrl_msg_wire.type == UDEV_CTRL_SET_LOG_LEVEL)
+ return ctrl_msg->ctrl_msg_wire.intval;
+ return -1;
+}
+
+int udev_ctrl_get_stop_exec_queue(struct udev_ctrl_msg *ctrl_msg) {
+ if (ctrl_msg->ctrl_msg_wire.type == UDEV_CTRL_STOP_EXEC_QUEUE)
+ return 1;
+ return -1;
+}
+
+int udev_ctrl_get_start_exec_queue(struct udev_ctrl_msg *ctrl_msg) {
+ if (ctrl_msg->ctrl_msg_wire.type == UDEV_CTRL_START_EXEC_QUEUE)
+ return 1;
+ return -1;
+}
+
+int udev_ctrl_get_reload(struct udev_ctrl_msg *ctrl_msg) {
+ if (ctrl_msg->ctrl_msg_wire.type == UDEV_CTRL_RELOAD)
+ return 1;
+ return -1;
+}
+
+const char *udev_ctrl_get_set_env(struct udev_ctrl_msg *ctrl_msg) {
+ if (ctrl_msg->ctrl_msg_wire.type == UDEV_CTRL_SET_ENV)
+ return ctrl_msg->ctrl_msg_wire.buf;
+ return NULL;
+}
+
+int udev_ctrl_get_set_children_max(struct udev_ctrl_msg *ctrl_msg) {
+ if (ctrl_msg->ctrl_msg_wire.type == UDEV_CTRL_SET_CHILDREN_MAX)
+ return ctrl_msg->ctrl_msg_wire.intval;
+ return -1;
+}
+
+int udev_ctrl_get_ping(struct udev_ctrl_msg *ctrl_msg) {
+ if (ctrl_msg->ctrl_msg_wire.type == UDEV_CTRL_PING)
+ return 1;
+ return -1;
+}
+
+int udev_ctrl_get_exit(struct udev_ctrl_msg *ctrl_msg) {
+ if (ctrl_msg->ctrl_msg_wire.type == UDEV_CTRL_EXIT)
+ return 1;
+ return -1;
+}