libsystemd-bus: rename to libsystemd

Documentation was updated to refer to either 'libsystemd' or 'sd-bus' in place
of libsystemd-bus.

1 files changed, 241 insertions, 0 deletions

diff --git a/src/libsystemd/bus-container.c b/src/libsystemd/bus-container.c
new file mode 100644
index 0000000000..d330363b6f
--- /dev/null
+++ b/src/libsystemd/bus-container.c
@@ -0,0 +1,241 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Lennart Poettering
+
+  systemd 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.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <unistd.h>
+#include <fcntl.h>
+
+#include "util.h"
+#include "fileio.h"
+#include "bus-internal.h"
+#include "bus-socket.h"
+#include "bus-container.h"
+
+int bus_container_connect_socket(sd_bus *b) {
+        _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, rootfd = -1;
+        pid_t leader, child;
+        siginfo_t si;
+        int r;
+
+        assert(b);
+        assert(b->input_fd < 0);
+        assert(b->output_fd < 0);
+
+        r = container_get_leader(b->machine, &leader);
+        if (r < 0)
+                return r;
+
+        r = namespace_open(leader, &pidnsfd, &mntnsfd, &rootfd);
+        if (r < 0)
+                return r;
+
+        b->input_fd = socket(b->sockaddr.sa.sa_family, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+        if (b->input_fd < 0)
+                return -errno;
+
+        b->output_fd = b->input_fd;
+
+        bus_socket_setup(b);
+
+        child = fork();
+        if (child < 0)
+                return -errno;
+
+        if (child == 0) {
+                pid_t grandchild;
+
+                r = namespace_enter(pidnsfd, mntnsfd, rootfd);
+                if (r < 0)
+                        _exit(255);
+
+                /* We just changed PID namespace, however it will only
+                 * take effect on the children we now fork. Hence,
+                 * let's fork another time, and connect from this
+                 * grandchild, so that SO_PEERCRED of our connection
+                 * comes from a process from within the container, and
+                 * not outside of it */
+
+                grandchild = fork();
+                if (grandchild < 0)
+                        _exit(255);
+
+                if (grandchild == 0) {
+
+                        r = connect(b->input_fd, &b->sockaddr.sa, b->sockaddr_size);
+                        if (r < 0) {
+                                if (errno == EINPROGRESS)
+                                        _exit(1);
+
+                                _exit(255);
+                        }
+
+                        _exit(EXIT_SUCCESS);
+                }
+
+                r = wait_for_terminate(grandchild, &si);
+                if (r < 0)
+                        _exit(255);
+
+                if (si.si_code != CLD_EXITED)
+                        _exit(255);
+
+                _exit(si.si_status);
+        }
+
+        r = wait_for_terminate(child, &si);
+        if (r < 0)
+                return r;
+
+        if (si.si_code != CLD_EXITED)
+                return -EIO;
+
+        if (si.si_status == 1)
+                return 1;
+
+        if (si.si_status != EXIT_SUCCESS)
+                return -EIO;
+
+        return bus_socket_start_auth(b);
+}
+
+int bus_container_connect_kernel(sd_bus *b) {
+        _cleanup_close_pipe_ int pair[2] = { -1, -1 };
+        _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, rootfd = -1;
+        union {
+                struct cmsghdr cmsghdr;
+                uint8_t buf[CMSG_SPACE(sizeof(int))];
+        } control = {};
+        struct msghdr mh = {
+                .msg_control = &control,
+                .msg_controllen = sizeof(control),
+        };
+        struct cmsghdr *cmsg;
+        pid_t leader, child;
+        siginfo_t si;
+        int r;
+        _cleanup_close_ int fd = -1;
+
+        assert(b);
+        assert(b->input_fd < 0);
+        assert(b->output_fd < 0);
+
+        r = container_get_leader(b->machine, &leader);
+        if (r < 0)
+                return r;
+
+        r = namespace_open(leader, &pidnsfd, &mntnsfd, &rootfd);
+        if (r < 0)
+                return r;
+
+        if (socketpair(AF_UNIX, SOCK_DGRAM, 0, pair) < 0)
+                return -errno;
+
+        child = fork();
+        if (child < 0)
+                return -errno;
+
+        if (child == 0) {
+                pid_t grandchild;
+
+                close_nointr_nofail(pair[0]);
+                pair[0] = -1;
+
+                r = namespace_enter(pidnsfd, mntnsfd, rootfd);
+                if (r < 0)
+                        _exit(EXIT_FAILURE);
+
+                /* We just changed PID namespace, however it will only
+                 * take effect on the children we now fork. Hence,
+                 * let's fork another time, and connect from this
+                 * grandchild, so that kdbus only sees the credentials
+                 * of this process which comes from within the
+                 * container, and not outside of it */
+
+                grandchild = fork();
+                if (grandchild < 0)
+                        _exit(EXIT_FAILURE);
+
+                if (grandchild == 0) {
+
+                        fd = open(b->kernel, O_RDWR|O_NOCTTY|O_CLOEXEC);
+                        if (fd < 0)
+                                _exit(EXIT_FAILURE);
+
+                        cmsg = CMSG_FIRSTHDR(&mh);
+                        cmsg->cmsg_level = SOL_SOCKET;
+                        cmsg->cmsg_type = SCM_RIGHTS;
+                        cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+                        memcpy(CMSG_DATA(cmsg), &fd, sizeof(int));
+
+                        mh.msg_controllen = cmsg->cmsg_len;
+
+                        if (sendmsg(pair[1], &mh, MSG_NOSIGNAL) < 0)
+                                _exit(EXIT_FAILURE);
+
+                        _exit(EXIT_SUCCESS);
+                }
+
+                r = wait_for_terminate(grandchild, &si);
+                if (r < 0)
+                        _exit(EXIT_FAILURE);
+
+                if (si.si_code != CLD_EXITED)
+                        _exit(EXIT_FAILURE);
+
+                _exit(si.si_status);
+        }
+
+        close_nointr_nofail(pair[1]);
+        pair[1] = -1;
+
+        r = wait_for_terminate(child, &si);
+        if (r < 0)
+                return r;
+
+        if (si.si_code != CLD_EXITED)
+                return -EIO;
+
+        if (si.si_status != EXIT_SUCCESS)
+                return -EIO;
+
+        if (recvmsg(pair[0], &mh, MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) < 0)
+                return -errno;
+
+        for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg))
+                if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
+                        int *fds;
+                        unsigned n_fds;
+
+                        fds = (int*) CMSG_DATA(cmsg);
+                        n_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
+
+                        if (n_fds != 1) {
+                                close_many(fds, n_fds);
+                                return -EIO;
+                        }
+
+                        fd = fds[0];
+                }
+
+        b->input_fd = b->output_fd = fd;
+        fd = -1;
+
+        return bus_kernel_take_fd(b);
+}