--- /dev/null
+/*-*- 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 <endian.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/poll.h>
+#include <byteswap.h>
+
+#include "util.h"
+#include "macro.h"
+#include "missing.h"
+#include "strv.h"
+#include "utf8.h"
+#include "sd-daemon.h"
+
+#include "sd-bus.h"
+#include "bus-socket.h"
+#include "bus-internal.h"
+#include "bus-message.h"
+
+#define SNDBUF_SIZE (8*1024*1024)
+
+static void iovec_advance(struct iovec iov[], unsigned *idx, size_t size) {
+
+ while (size > 0) {
+ struct iovec *i = iov + *idx;
+
+ if (i->iov_len > size) {
+ i->iov_base = (uint8_t*) i->iov_base + size;
+ i->iov_len -= size;
+ return;
+ }
+
+ size -= i->iov_len;
+
+ i->iov_base = NULL;
+ i->iov_len = 0;
+
+ (*idx) ++;
+ }
+}
+
+static int append_iovec(sd_bus_message *m, const void *p, size_t sz) {
+ assert(m);
+ assert(p);
+ assert(sz > 0);
+
+ m->iovec[m->n_iovec].iov_base = (void*) p;
+ m->iovec[m->n_iovec].iov_len = sz;
+ m->n_iovec++;
+
+ return 0;
+}
+
+static int bus_message_setup_iovec(sd_bus_message *m) {
+ struct bus_body_part *part;
+ unsigned n, i;
+ int r;
+
+ assert(m);
+ assert(m->sealed);
+
+ if (m->n_iovec > 0)
+ return 0;
+
+ assert(!m->iovec);
+
+ n = 1 + m->n_body_parts;
+ if (n < ELEMENTSOF(m->iovec_fixed))
+ m->iovec = m->iovec_fixed;
+ else {
+ m->iovec = new(struct iovec, n);
+ if (!m->iovec) {
+ r = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ r = append_iovec(m, m->header, BUS_MESSAGE_BODY_BEGIN(m));
+ if (r < 0)
+ goto fail;
+
+ MESSAGE_FOREACH_PART(part, i, m) {
+ r = bus_body_part_map(part);
+ if (r < 0)
+ goto fail;
+
+ r = append_iovec(m, part->data, part->size);
+ if (r < 0)
+ goto fail;
+ }
+
+ assert(n == m->n_iovec);
+
+ return 0;
+
+fail:
+ m->poisoned = true;
+ return r;
+}
+
+bool bus_socket_auth_needs_write(sd_bus *b) {
+
+ unsigned i;
+
+ if (b->auth_index >= ELEMENTSOF(b->auth_iovec))
+ return false;
+
+ for (i = b->auth_index; i < ELEMENTSOF(b->auth_iovec); i++) {
+ struct iovec *j = b->auth_iovec + i;
+
+ if (j->iov_len > 0)
+ return true;
+ }
+
+ return false;
+}
+
+static int bus_socket_write_auth(sd_bus *b) {
+ ssize_t k;
+
+ assert(b);
+ assert(b->state == BUS_AUTHENTICATING);
+
+ if (!bus_socket_auth_needs_write(b))
+ return 0;
+
+ if (b->prefer_writev)
+ k = writev(b->output_fd, b->auth_iovec + b->auth_index, ELEMENTSOF(b->auth_iovec) - b->auth_index);
+ else {
+ struct msghdr mh;
+ zero(mh);
+
+ mh.msg_iov = b->auth_iovec + b->auth_index;
+ mh.msg_iovlen = ELEMENTSOF(b->auth_iovec) - b->auth_index;
+
+ k = sendmsg(b->output_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
+ if (k < 0 && errno == ENOTSOCK) {
+ b->prefer_writev = true;
+ k = writev(b->output_fd, b->auth_iovec + b->auth_index, ELEMENTSOF(b->auth_iovec) - b->auth_index);
+ }
+ }
+
+ if (k < 0)
+ return errno == EAGAIN ? 0 : -errno;
+
+ iovec_advance(b->auth_iovec, &b->auth_index, (size_t) k);
+ return 1;
+}
+
+static int bus_socket_auth_verify_client(sd_bus *b) {
+ char *e, *f, *start;
+ sd_id128_t peer;
+ unsigned i;
+ int r;
+
+ assert(b);
+
+ /* We expect two response lines: "OK" and possibly
+ * "AGREE_UNIX_FD" */
+
+ e = memmem(b->rbuffer, b->rbuffer_size, "\r\n", 2);
+ if (!e)
+ return 0;
+
+ if (b->hello_flags & KDBUS_HELLO_ACCEPT_FD) {
+ f = memmem(e + 2, b->rbuffer_size - (e - (char*) b->rbuffer) - 2, "\r\n", 2);
+ if (!f)
+ return 0;
+
+ start = f + 2;
+ } else {
+ f = NULL;
+ start = e + 2;
+ }
+
+ /* Nice! We got all the lines we need. First check the OK
+ * line */
+
+ if (e - (char*) b->rbuffer != 3 + 32)
+ return -EPERM;
+
+ if (memcmp(b->rbuffer, "OK ", 3))
+ return -EPERM;
+
+ b->auth = b->anonymous_auth ? BUS_AUTH_ANONYMOUS : BUS_AUTH_EXTERNAL;
+
+ for (i = 0; i < 32; i += 2) {
+ int x, y;
+
+ x = unhexchar(((char*) b->rbuffer)[3 + i]);
+ y = unhexchar(((char*) b->rbuffer)[3 + i + 1]);
+
+ if (x < 0 || y < 0)
+ return -EINVAL;
+
+ peer.bytes[i/2] = ((uint8_t) x << 4 | (uint8_t) y);
+ }
+
+ if (!sd_id128_equal(b->server_id, SD_ID128_NULL) &&
+ !sd_id128_equal(b->server_id, peer))
+ return -EPERM;
+
+ b->server_id = peer;
+
+ /* And possibly check the second line, too */
+
+ if (f)
+ b->can_fds =
+ (f - e == sizeof("\r\nAGREE_UNIX_FD") - 1) &&
+ memcmp(e + 2, "AGREE_UNIX_FD", sizeof("AGREE_UNIX_FD") - 1) == 0;
+
+ b->rbuffer_size -= (start - (char*) b->rbuffer);
+ memmove(b->rbuffer, start, b->rbuffer_size);
+
+ r = bus_start_running(b);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static bool line_equals(const char *s, size_t m, const char *line) {
+ size_t l;
+
+ l = strlen(line);
+ if (l != m)
+ return false;
+
+ return memcmp(s, line, l) == 0;
+}
+
+static bool line_begins(const char *s, size_t m, const char *word) {
+ size_t l;
+
+ l = strlen(word);
+ if (m < l)
+ return false;
+
+ if (memcmp(s, word, l) != 0)
+ return false;
+
+ return m == l || (m > l && s[l] == ' ');
+}
+
+static int verify_anonymous_token(sd_bus *b, const char *p, size_t l) {
+ _cleanup_free_ char *token = NULL;
+
+ if (!b->anonymous_auth)
+ return 0;
+
+ if (l <= 0)
+ return 1;
+
+ assert(p[0] == ' ');
+ p++; l--;
+
+ if (l % 2 != 0)
+ return 0;
+ token = unhexmem(p, l);
+ if (!token)
+ return -ENOMEM;
+
+ if (memchr(token, 0, l/2))
+ return 0;
+
+ return !!utf8_is_valid(token);
+}
+
+static int verify_external_token(sd_bus *b, const char *p, size_t l) {
+ _cleanup_free_ char *token = NULL;
+ uid_t u;
+ int r;
+
+ /* We don't do any real authentication here. Instead, we if
+ * the owner of this bus wanted authentication he should have
+ * checked SO_PEERCRED before even creating the bus object. */
+
+ if (!b->anonymous_auth && !b->ucred_valid)
+ return 0;
+
+ if (l <= 0)
+ return 1;
+
+ assert(p[0] == ' ');
+ p++; l--;
+
+ if (l % 2 != 0)
+ return 0;
+
+ token = unhexmem(p, l);
+ if (!token)
+ return -ENOMEM;
+
+ if (memchr(token, 0, l/2))
+ return 0;
+
+ r = parse_uid(token, &u);
+ if (r < 0)
+ return 0;
+
+ /* We ignore the passed value if anonymous authentication is
+ * on anyway. */
+ if (!b->anonymous_auth && u != b->ucred.uid)
+ return 0;
+
+ return 1;
+}
+
+static int bus_socket_auth_write(sd_bus *b, const char *t) {
+ char *p;
+ size_t l;
+
+ assert(b);
+ assert(t);
+
+ /* We only make use of the first iovec */
+ assert(b->auth_index == 0 || b->auth_index == 1);
+
+ l = strlen(t);
+ p = malloc(b->auth_iovec[0].iov_len + l);
+ if (!p)
+ return -ENOMEM;
+
+ memcpy(p, b->auth_iovec[0].iov_base, b->auth_iovec[0].iov_len);
+ memcpy(p + b->auth_iovec[0].iov_len, t, l);
+
+ b->auth_iovec[0].iov_base = p;
+ b->auth_iovec[0].iov_len += l;
+
+ free(b->auth_buffer);
+ b->auth_buffer = p;
+ b->auth_index = 0;
+ return 0;
+}
+
+static int bus_socket_auth_write_ok(sd_bus *b) {
+ char t[3 + 32 + 2 + 1];
+
+ assert(b);
+
+ snprintf(t, sizeof(t), "OK " SD_ID128_FORMAT_STR "\r\n", SD_ID128_FORMAT_VAL(b->server_id));
+ char_array_0(t);
+
+ return bus_socket_auth_write(b, t);
+}
+
+static int bus_socket_auth_verify_server(sd_bus *b) {
+ char *e;
+ const char *line;
+ size_t l;
+ bool processed = false;
+ int r;
+
+ assert(b);
+
+ if (b->rbuffer_size < 1)
+ return 0;
+
+ /* First char must be a NUL byte */
+ if (*(char*) b->rbuffer != 0)
+ return -EIO;
+
+ if (b->rbuffer_size < 3)
+ return 0;
+
+ /* Begin with the first line */
+ if (b->auth_rbegin <= 0)
+ b->auth_rbegin = 1;
+
+ for (;;) {
+ /* Check if line is complete */
+ line = (char*) b->rbuffer + b->auth_rbegin;
+ e = memmem(line, b->rbuffer_size - b->auth_rbegin, "\r\n", 2);
+ if (!e)
+ return processed;
+
+ l = e - line;
+
+ if (line_begins(line, l, "AUTH ANONYMOUS")) {
+
+ r = verify_anonymous_token(b, line + 14, l - 14);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ r = bus_socket_auth_write(b, "REJECTED\r\n");
+ else {
+ b->auth = BUS_AUTH_ANONYMOUS;
+ r = bus_socket_auth_write_ok(b);
+ }
+
+ } else if (line_begins(line, l, "AUTH EXTERNAL")) {
+
+ r = verify_external_token(b, line + 13, l - 13);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ r = bus_socket_auth_write(b, "REJECTED\r\n");
+ else {
+ b->auth = BUS_AUTH_EXTERNAL;
+ r = bus_socket_auth_write_ok(b);
+ }
+
+ } else if (line_begins(line, l, "AUTH"))
+ r = bus_socket_auth_write(b, "REJECTED EXTERNAL ANONYMOUS\r\n");
+ else if (line_equals(line, l, "CANCEL") ||
+ line_begins(line, l, "ERROR")) {
+
+ b->auth = _BUS_AUTH_INVALID;
+ r = bus_socket_auth_write(b, "REJECTED\r\n");
+
+ } else if (line_equals(line, l, "BEGIN")) {
+
+ if (b->auth == _BUS_AUTH_INVALID)
+ r = bus_socket_auth_write(b, "ERROR\r\n");
+ else {
+ /* We can't leave from the auth phase
+ * before we haven't written
+ * everything queued, so let's check
+ * that */
+
+ if (bus_socket_auth_needs_write(b))
+ return 1;
+
+ b->rbuffer_size -= (e + 2 - (char*) b->rbuffer);
+ memmove(b->rbuffer, e + 2, b->rbuffer_size);
+ return bus_start_running(b);
+ }
+
+ } else if (line_begins(line, l, "DATA")) {
+
+ if (b->auth == _BUS_AUTH_INVALID)
+ r = bus_socket_auth_write(b, "ERROR\r\n");
+ else {
+ if (b->auth == BUS_AUTH_ANONYMOUS)
+ r = verify_anonymous_token(b, line + 4, l - 4);
+ else
+ r = verify_external_token(b, line + 4, l - 4);
+
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ b->auth = _BUS_AUTH_INVALID;
+ r = bus_socket_auth_write(b, "REJECTED\r\n");
+ } else
+ r = bus_socket_auth_write_ok(b);
+ }
+ } else if (line_equals(line, l, "NEGOTIATE_UNIX_FD")) {
+ if (b->auth == _BUS_AUTH_INVALID || !(b->hello_flags & KDBUS_HELLO_ACCEPT_FD))
+ r = bus_socket_auth_write(b, "ERROR\r\n");
+ else {
+ b->can_fds = true;
+ r = bus_socket_auth_write(b, "AGREE_UNIX_FD\r\n");
+ }
+ } else
+ r = bus_socket_auth_write(b, "ERROR\r\n");
+
+ if (r < 0)
+ return r;
+
+ b->auth_rbegin = e + 2 - (char*) b->rbuffer;
+
+ processed = true;
+ }
+}
+
+static int bus_socket_auth_verify(sd_bus *b) {
+ assert(b);
+
+ if (b->is_server)
+ return bus_socket_auth_verify_server(b);
+ else
+ return bus_socket_auth_verify_client(b);
+}
+
+static int bus_socket_read_auth(sd_bus *b) {
+ struct msghdr mh;
+ struct iovec iov;
+ size_t n;
+ ssize_t k;
+ int r;
+ void *p;
+ union {
+ struct cmsghdr cmsghdr;
+ uint8_t buf[CMSG_SPACE(sizeof(int) * BUS_FDS_MAX) +
+ CMSG_SPACE(sizeof(struct ucred)) +
+ CMSG_SPACE(NAME_MAX)]; /*selinux label */
+ } control;
+ struct cmsghdr *cmsg;
+ bool handle_cmsg = false;
+
+ assert(b);
+ assert(b->state == BUS_AUTHENTICATING);
+
+ r = bus_socket_auth_verify(b);
+ if (r != 0)
+ return r;
+
+ n = MAX(256u, b->rbuffer_size * 2);
+
+ if (n > BUS_AUTH_SIZE_MAX)
+ n = BUS_AUTH_SIZE_MAX;
+
+ if (b->rbuffer_size >= n)
+ return -ENOBUFS;
+
+ p = realloc(b->rbuffer, n);
+ if (!p)
+ return -ENOMEM;
+
+ b->rbuffer = p;
+
+ zero(iov);
+ iov.iov_base = (uint8_t*) b->rbuffer + b->rbuffer_size;
+ iov.iov_len = n - b->rbuffer_size;
+
+ if (b->prefer_readv)
+ k = readv(b->input_fd, &iov, 1);
+ else {
+ zero(mh);
+ mh.msg_iov = &iov;
+ mh.msg_iovlen = 1;
+ mh.msg_control = &control;
+ mh.msg_controllen = sizeof(control);
+
+ k = recvmsg(b->input_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC);
+ if (k < 0 && errno == ENOTSOCK) {
+ b->prefer_readv = true;
+ k = readv(b->input_fd, &iov, 1);
+ } else
+ handle_cmsg = true;
+ }
+ if (k < 0)
+ return errno == EAGAIN ? 0 : -errno;
+ if (k == 0)
+ return -ECONNRESET;
+
+ b->rbuffer_size += k;
+
+ if (handle_cmsg) {
+ for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg)) {
+ if (cmsg->cmsg_level == SOL_SOCKET &&
+ cmsg->cmsg_type == SCM_RIGHTS) {
+ int j;
+
+ /* Whut? We received fds during the auth
+ * protocol? Somebody is playing games with
+ * us. Close them all, and fail */
+ j = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
+ close_many((int*) CMSG_DATA(cmsg), j);
+ return -EIO;
+
+ } else if (cmsg->cmsg_level == SOL_SOCKET &&
+ cmsg->cmsg_type == SCM_CREDENTIALS &&
+ cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred))) {
+
+ /* Ignore bogus data, which we might
+ * get on socketpair() sockets */
+ if (((struct ucred*) CMSG_DATA(cmsg))->pid != 0) {
+ memcpy(&b->ucred, CMSG_DATA(cmsg), sizeof(struct ucred));
+ b->ucred_valid = true;
+ }
+
+ } else if (cmsg->cmsg_level == SOL_SOCKET &&
+ cmsg->cmsg_type == SCM_SECURITY) {
+
+ size_t l;
+
+ l = cmsg->cmsg_len - CMSG_LEN(0);
+ if (l > 0) {
+ memcpy(&b->label, CMSG_DATA(cmsg), l);
+ b->label[l] = 0;
+ }
+ }
+ }
+ }
+
+ r = bus_socket_auth_verify(b);
+ if (r != 0)
+ return r;
+
+ return 1;
+}
+
+void bus_socket_setup(sd_bus *b) {
+ int enable;
+
+ assert(b);
+
+ /* Enable SO_PASSCRED + SO_PASSEC. We try this on any
+ * socket, just in case. */
+ enable = !b->bus_client;
+ setsockopt(b->input_fd, SOL_SOCKET, SO_PASSCRED, &enable, sizeof(enable));
+
+ enable = !b->bus_client && (b->attach_flags & KDBUS_ATTACH_SECLABEL);
+ setsockopt(b->input_fd, SOL_SOCKET, SO_PASSSEC, &enable, sizeof(enable));
+
+ /* Increase the buffers to 8 MB */
+ fd_inc_rcvbuf(b->input_fd, SNDBUF_SIZE);
+ fd_inc_sndbuf(b->output_fd, SNDBUF_SIZE);
+
+ b->is_kernel = false;
+ b->message_version = 1;
+ b->message_endian = 0;
+}
+
+static void bus_get_peercred(sd_bus *b) {
+ assert(b);
+
+ /* Get the peer for socketpair() sockets */
+ b->ucred_valid = getpeercred(b->input_fd, &b->ucred) >= 0;
+}
+
+static int bus_socket_start_auth_client(sd_bus *b) {
+ size_t l;
+ const char *auth_suffix, *auth_prefix;
+
+ assert(b);
+
+ if (b->anonymous_auth) {
+ auth_prefix = "\0AUTH ANONYMOUS ";
+
+ /* For ANONYMOUS auth we send some arbitrary "trace" string */
+ l = 9;
+ b->auth_buffer = hexmem("anonymous", l);
+ } else {
+ char text[20 + 1]; /* enough space for a 64bit integer plus NUL */
+
+ auth_prefix = "\0AUTH EXTERNAL ";
+
+ snprintf(text, sizeof(text), "%lu", (unsigned long) geteuid());
+ char_array_0(text);
+
+ l = strlen(text);
+ b->auth_buffer = hexmem(text, l);
+ }
+
+ if (!b->auth_buffer)
+ return -ENOMEM;
+
+ if (b->hello_flags & KDBUS_HELLO_ACCEPT_FD)
+ auth_suffix = "\r\nNEGOTIATE_UNIX_FD\r\nBEGIN\r\n";
+ else
+ auth_suffix = "\r\nBEGIN\r\n";
+
+ b->auth_iovec[0].iov_base = (void*) auth_prefix;
+ b->auth_iovec[0].iov_len = 1 + strlen(auth_prefix + 1);
+ b->auth_iovec[1].iov_base = (void*) b->auth_buffer;
+ b->auth_iovec[1].iov_len = l * 2;
+ b->auth_iovec[2].iov_base = (void*) auth_suffix;
+ b->auth_iovec[2].iov_len = strlen(auth_suffix);
+
+ return bus_socket_write_auth(b);
+}
+
+int bus_socket_start_auth(sd_bus *b) {
+ assert(b);
+
+ bus_get_peercred(b);
+
+ b->state = BUS_AUTHENTICATING;
+ b->auth_timeout = now(CLOCK_MONOTONIC) + BUS_DEFAULT_TIMEOUT;
+
+ if (sd_is_socket(b->input_fd, AF_UNIX, 0, 0) <= 0)
+ b->hello_flags &= ~KDBUS_HELLO_ACCEPT_FD;
+
+ if (b->output_fd != b->input_fd)
+ if (sd_is_socket(b->output_fd, AF_UNIX, 0, 0) <= 0)
+ b->hello_flags &= ~KDBUS_HELLO_ACCEPT_FD;
+
+ if (b->is_server)
+ return bus_socket_read_auth(b);
+ else
+ return bus_socket_start_auth_client(b);
+}
+
+int bus_socket_connect(sd_bus *b) {
+ int r;
+
+ assert(b);
+ assert(b->input_fd < 0);
+ assert(b->output_fd < 0);
+ assert(b->sockaddr.sa.sa_family != AF_UNSPEC);
+
+ 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);
+
+ r = connect(b->input_fd, &b->sockaddr.sa, b->sockaddr_size);
+ if (r < 0) {
+ if (errno == EINPROGRESS)
+ return 1;
+
+ return -errno;
+ }
+
+ return bus_socket_start_auth(b);
+}
+
+int bus_socket_exec(sd_bus *b) {
+ int s[2], r;
+ pid_t pid;
+
+ assert(b);
+ assert(b->input_fd < 0);
+ assert(b->output_fd < 0);
+ assert(b->exec_path);
+
+ r = socketpair(AF_UNIX, SOCK_STREAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, s);
+ if (r < 0)
+ return -errno;
+
+ pid = fork();
+ if (pid < 0) {
+ close_pipe(s);
+ return -errno;
+ }
+ if (pid == 0) {
+ /* Child */
+
+ reset_all_signal_handlers();
+
+ close_all_fds(s+1, 1);
+
+ assert_se(dup3(s[1], STDIN_FILENO, 0) == STDIN_FILENO);
+ assert_se(dup3(s[1], STDOUT_FILENO, 0) == STDOUT_FILENO);
+
+ if (s[1] != STDIN_FILENO && s[1] != STDOUT_FILENO)
+ close_nointr_nofail(s[1]);
+
+ fd_cloexec(STDIN_FILENO, false);
+ fd_cloexec(STDOUT_FILENO, false);
+ fd_nonblock(STDIN_FILENO, false);
+ fd_nonblock(STDOUT_FILENO, false);
+
+ if (b->exec_argv)
+ execvp(b->exec_path, b->exec_argv);
+ else {
+ const char *argv[] = { b->exec_path, NULL };
+ execvp(b->exec_path, (char**) argv);
+ }
+
+ _exit(EXIT_FAILURE);
+ }
+
+ close_nointr_nofail(s[1]);
+ b->output_fd = b->input_fd = s[0];
+
+ bus_socket_setup(b);
+
+ return bus_socket_start_auth(b);
+}
+
+int bus_socket_take_fd(sd_bus *b) {
+ assert(b);
+
+ bus_socket_setup(b);
+
+ return bus_socket_start_auth(b);
+}
+
+int bus_socket_write_message(sd_bus *bus, sd_bus_message *m, size_t *idx) {
+ struct iovec *iov;
+ ssize_t k;
+ size_t n;
+ unsigned j;
+ int r;
+
+ assert(bus);
+ assert(m);
+ assert(idx);
+ assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
+
+ if (*idx >= BUS_MESSAGE_SIZE(m))
+ return 0;
+
+ r = bus_message_setup_iovec(m);
+ if (r < 0)
+ return r;
+
+ n = m->n_iovec * sizeof(struct iovec);
+ iov = alloca(n);
+ memcpy(iov, m->iovec, n);
+
+ j = 0;
+ iovec_advance(iov, &j, *idx);
+
+ if (bus->prefer_writev)
+ k = writev(bus->output_fd, iov, m->n_iovec);
+ else {
+ struct msghdr mh;
+ zero(mh);
+
+ if (m->n_fds > 0) {
+ struct cmsghdr *control;
+ control = alloca(CMSG_SPACE(sizeof(int) * m->n_fds));
+
+ mh.msg_control = control;
+ control->cmsg_level = SOL_SOCKET;
+ control->cmsg_type = SCM_RIGHTS;
+ mh.msg_controllen = control->cmsg_len = CMSG_LEN(sizeof(int) * m->n_fds);
+ memcpy(CMSG_DATA(control), m->fds, sizeof(int) * m->n_fds);
+ }
+
+ mh.msg_iov = iov;
+ mh.msg_iovlen = m->n_iovec;
+
+ k = sendmsg(bus->output_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
+ if (k < 0 && errno == ENOTSOCK) {
+ bus->prefer_writev = true;
+ k = writev(bus->output_fd, iov, m->n_iovec);
+ }
+ }
+
+ if (k < 0)
+ return errno == EAGAIN ? 0 : -errno;
+
+ *idx += (size_t) k;
+ return 1;
+}
+
+static int bus_socket_read_message_need(sd_bus *bus, size_t *need) {
+ uint32_t a, b;
+ uint8_t e;
+ uint64_t sum;
+
+ assert(bus);
+ assert(need);
+ assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
+
+ if (bus->rbuffer_size < sizeof(struct bus_header)) {
+ *need = sizeof(struct bus_header) + 8;
+
+ /* Minimum message size:
+ *
+ * Header +
+ *
+ * Method Call: +2 string headers
+ * Signal: +3 string headers
+ * Method Error: +1 string headers
+ * +1 uint32 headers
+ * Method Reply: +1 uint32 headers
+ *
+ * A string header is at least 9 bytes
+ * A uint32 header is at least 8 bytes
+ *
+ * Hence the minimum message size of a valid message
+ * is header + 8 bytes */
+
+ return 0;
+ }
+
+ a = ((const uint32_t*) bus->rbuffer)[1];
+ b = ((const uint32_t*) bus->rbuffer)[3];
+
+ e = ((const uint8_t*) bus->rbuffer)[0];
+ if (e == BUS_LITTLE_ENDIAN) {
+ a = le32toh(a);
+ b = le32toh(b);
+ } else if (e == BUS_BIG_ENDIAN) {
+ a = be32toh(a);
+ b = be32toh(b);
+ } else
+ return -EBADMSG;
+
+ sum = (uint64_t) sizeof(struct bus_header) + (uint64_t) ALIGN_TO(b, 8) + (uint64_t) a;
+ if (sum >= BUS_MESSAGE_SIZE_MAX)
+ return -ENOBUFS;
+
+ *need = (size_t) sum;
+ return 0;
+}
+
+static int bus_socket_make_message(sd_bus *bus, size_t size) {
+ sd_bus_message *t;
+ void *b;
+ int r;
+
+ assert(bus);
+ assert(bus->rbuffer_size >= size);
+ assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
+
+ r = bus_rqueue_make_room(bus);
+ if (r < 0)
+ return r;
+
+ if (bus->rbuffer_size > size) {
+ b = memdup((const uint8_t*) bus->rbuffer + size,
+ bus->rbuffer_size - size);
+ if (!b)
+ return -ENOMEM;
+ } else
+ b = NULL;
+
+ r = bus_message_from_malloc(bus,
+ bus->rbuffer, size,
+ bus->fds, bus->n_fds,
+ !bus->bus_client && bus->ucred_valid ? &bus->ucred : NULL,
+ !bus->bus_client && bus->label[0] ? bus->label : NULL,
+ &t);
+ if (r < 0) {
+ free(b);
+ return r;
+ }
+
+ bus->rbuffer = b;
+ bus->rbuffer_size -= size;
+
+ bus->fds = NULL;
+ bus->n_fds = 0;
+
+ bus->rqueue[bus->rqueue_size++] = t;
+
+ return 1;
+}
+
+int bus_socket_read_message(sd_bus *bus) {
+ struct msghdr mh;
+ struct iovec iov;
+ ssize_t k;
+ size_t need;
+ int r;
+ void *b;
+ union {
+ struct cmsghdr cmsghdr;
+ uint8_t buf[CMSG_SPACE(sizeof(int) * BUS_FDS_MAX) +
+ CMSG_SPACE(sizeof(struct ucred)) +
+ CMSG_SPACE(NAME_MAX)]; /*selinux label */
+ } control;
+ struct cmsghdr *cmsg;
+ bool handle_cmsg = false;
+
+ assert(bus);
+ assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
+
+ r = bus_socket_read_message_need(bus, &need);
+ if (r < 0)
+ return r;
+
+ if (bus->rbuffer_size >= need)
+ return bus_socket_make_message(bus, need);
+
+ b = realloc(bus->rbuffer, need);
+ if (!b)
+ return -ENOMEM;
+
+ bus->rbuffer = b;
+
+ zero(iov);
+ iov.iov_base = (uint8_t*) bus->rbuffer + bus->rbuffer_size;
+ iov.iov_len = need - bus->rbuffer_size;
+
+ if (bus->prefer_readv)
+ k = readv(bus->input_fd, &iov, 1);
+ else {
+ zero(mh);
+ mh.msg_iov = &iov;
+ mh.msg_iovlen = 1;
+ mh.msg_control = &control;
+ mh.msg_controllen = sizeof(control);
+
+ k = recvmsg(bus->input_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC);
+ if (k < 0 && errno == ENOTSOCK) {
+ bus->prefer_readv = true;
+ k = readv(bus->input_fd, &iov, 1);
+ } else
+ handle_cmsg = true;
+ }
+ if (k < 0)
+ return errno == EAGAIN ? 0 : -errno;
+ if (k == 0)
+ return -ECONNRESET;
+
+ bus->rbuffer_size += k;
+
+ if (handle_cmsg) {
+ for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg)) {
+ if (cmsg->cmsg_level == SOL_SOCKET &&
+ cmsg->cmsg_type == SCM_RIGHTS) {
+ int n, *f;
+
+ n = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
+
+ if (!bus->can_fds) {
+ /* Whut? We received fds but this
+ * isn't actually enabled? Close them,
+ * and fail */
+
+ close_many((int*) CMSG_DATA(cmsg), n);
+ return -EIO;
+ }
+
+ f = realloc(bus->fds, sizeof(int) + (bus->n_fds + n));
+ if (!f) {
+ close_many((int*) CMSG_DATA(cmsg), n);
+ return -ENOMEM;
+ }
+
+ memcpy(f + bus->n_fds, CMSG_DATA(cmsg), n * sizeof(int));
+ bus->fds = f;
+ bus->n_fds += n;
+ } else if (cmsg->cmsg_level == SOL_SOCKET &&
+ cmsg->cmsg_type == SCM_CREDENTIALS &&
+ cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred))) {
+
+ /* Ignore bogus data, which we might
+ * get on socketpair() sockets */
+ if (((struct ucred*) CMSG_DATA(cmsg))->pid != 0) {
+ memcpy(&bus->ucred, CMSG_DATA(cmsg), sizeof(struct ucred));
+ bus->ucred_valid = true;
+ }
+
+ } else if (cmsg->cmsg_level == SOL_SOCKET &&
+ cmsg->cmsg_type == SCM_SECURITY) {
+
+ size_t l;
+ l = cmsg->cmsg_len - CMSG_LEN(0);
+ if (l > 0) {
+ memcpy(&bus->label, CMSG_DATA(cmsg), l);
+ bus->label[l] = 0;
+ }
+ }
+ }
+ }
+
+ r = bus_socket_read_message_need(bus, &need);
+ if (r < 0)
+ return r;
+
+ if (bus->rbuffer_size >= need)
+ return bus_socket_make_message(bus, need);
+
+ return 1;
+}
+
+int bus_socket_process_opening(sd_bus *b) {
+ int error = 0;
+ socklen_t slen = sizeof(error);
+ struct pollfd p = {
+ .fd = b->output_fd,
+ .events = POLLOUT,
+ };
+ int r;
+
+ assert(b->state == BUS_OPENING);
+
+ r = poll(&p, 1, 0);
+ if (r < 0)
+ return -errno;
+
+ if (!(p.revents & (POLLOUT|POLLERR|POLLHUP)))
+ return 0;
+
+ r = getsockopt(b->output_fd, SOL_SOCKET, SO_ERROR, &error, &slen);
+ if (r < 0)
+ b->last_connect_error = errno;
+ else if (error != 0)
+ b->last_connect_error = error;
+ else if (p.revents & (POLLERR|POLLHUP))
+ b->last_connect_error = ECONNREFUSED;
+ else
+ return bus_socket_start_auth(b);
+
+ return bus_next_address(b);
+}
+
+int bus_socket_process_authenticating(sd_bus *b) {
+ int r;
+
+ assert(b);
+ assert(b->state == BUS_AUTHENTICATING);
+
+ if (now(CLOCK_MONOTONIC) >= b->auth_timeout)
+ return -ETIMEDOUT;
+
+ r = bus_socket_write_auth(b);
+ if (r != 0)
+ return r;
+
+ return bus_socket_read_auth(b);
+}
~ianmdlvl / elogind.git / blobdiff