summaryrefslogtreecommitdiff
path: root/src/nspawn/nspawn.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/nspawn/nspawn.c')
-rw-r--r--src/nspawn/nspawn.c408
1 files changed, 357 insertions, 51 deletions
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index 59f6f38a49..2b1feb6aa3 100644
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -93,11 +93,22 @@
#include "cap-list.h"
#include "btrfs-util.h"
#include "machine-image.h"
+#include "list.h"
+#include "in-addr-util.h"
+#include "fw-util.h"
+#include "local-addresses.h"
#ifdef HAVE_SECCOMP
#include "seccomp-util.h"
#endif
+typedef struct ExposePort {
+ int protocol;
+ uint16_t host_port;
+ uint16_t container_port;
+ LIST_FIELDS(struct ExposePort, ports);
+} ExposePort;
+
typedef enum ContainerStatus {
CONTAINER_TERMINATED,
CONTAINER_REBOOTED
@@ -172,6 +183,7 @@ static const char *arg_network_bridge = NULL;
static unsigned long arg_personality = 0xffffffffLU;
static char *arg_image = NULL;
static Volatile arg_volatile = VOLATILE_NO;
+static ExposePort *arg_expose_ports = NULL;
static void help(void) {
printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
@@ -203,6 +215,8 @@ static void help(void) {
" Add a virtual ethernet connection between host\n"
" and container and add it to an existing bridge on\n"
" the host\n"
+ " -p --port=[PROTOCOL:]HOSTPORT[:CONTAINERPORT]\n"
+ " Expose a container IP port ont the host\n"
" -Z --selinux-context=SECLABEL\n"
" Set the SELinux security context to be used by\n"
" processes in the container\n"
@@ -225,8 +239,8 @@ static void help(void) {
" --register=BOOLEAN Register container as machine\n"
" --keep-unit Do not register a scope for the machine, reuse\n"
" the service unit nspawn is running in\n"
- " --volatile[=MODE] Run the system in volatile mode\n",
- program_invocation_short_name);
+ " --volatile[=MODE] Run the system in volatile mode\n"
+ , program_invocation_short_name);
}
static int set_sanitized_path(char **b, const char *path) {
@@ -309,6 +323,7 @@ static int parse_argv(int argc, char *argv[]) {
{ "personality", required_argument, NULL, ARG_PERSONALITY },
{ "image", required_argument, NULL, 'i' },
{ "volatile", optional_argument, NULL, ARG_VOLATILE },
+ { "port", required_argument, NULL, 'p' },
{}
};
@@ -318,7 +333,7 @@ static int parse_argv(int argc, char *argv[]) {
assert(argc >= 0);
assert(argv);
- while ((c = getopt_long(argc, argv, "+hD:u:bL:M:jS:Z:qi:x", options, NULL)) >= 0)
+ while ((c = getopt_long(argc, argv, "+hD:u:bL:M:jS:Z:qi:xp:", options, NULL)) >= 0)
switch (c) {
@@ -643,6 +658,65 @@ static int parse_argv(int argc, char *argv[]) {
break;
+ case 'p': {
+ const char *split, *e;
+ uint16_t container_port, host_port;
+ int protocol;
+ ExposePort *p;
+
+ if ((e = startswith(optarg, "tcp:")))
+ protocol = IPPROTO_TCP;
+ else if ((e = startswith(optarg, "udp:")))
+ protocol = IPPROTO_UDP;
+ else {
+ e = optarg;
+ protocol = IPPROTO_TCP;
+ }
+
+ split = strchr(e, ':');
+ if (split) {
+ char v[split - e + 1];
+
+ memcpy(v, e, split - e);
+ v[split - e] = 0;
+
+ r = safe_atou16(v, &host_port);
+ if (r < 0 || host_port <= 0) {
+ log_error("Failed to parse host port: %s", optarg);
+ return -EINVAL;
+ }
+
+ r = safe_atou16(split + 1, &container_port);
+ } else {
+ r = safe_atou16(e, &container_port);
+ host_port = container_port;
+ }
+
+ if (r < 0 || container_port <= 0) {
+ log_error("Failed to parse host port: %s", optarg);
+ return -EINVAL;
+ }
+
+ LIST_FOREACH(ports, p, arg_expose_ports) {
+ if (p->protocol == protocol && p->host_port == host_port) {
+ log_error("Duplicate port specification: %s", optarg);
+ return -EINVAL;
+ }
+ }
+
+ p = new(ExposePort, 1);
+ if (!p)
+ return log_oom();
+
+ p->protocol = protocol;
+ p->host_port = host_port;
+ p->container_port = container_port;
+
+ LIST_PREPEND(ports, arg_expose_ports, p);
+
+ break;
+ }
+
case '?':
return -EINVAL;
@@ -698,6 +772,11 @@ static int parse_argv(int argc, char *argv[]) {
return -EINVAL;
}
+ if (arg_expose_ports && !arg_private_network) {
+ log_error("Cannot use --port= without private networking.");
+ return -EINVAL;
+ }
+
arg_retain = (arg_retain | plus | (arg_private_network ? 1ULL << CAP_NET_ADMIN : 0)) & ~minus;
return 1;
@@ -1349,8 +1428,8 @@ static int setup_dev_console(const char *dest, const char *console) {
static int setup_kmsg(const char *dest, int kmsg_socket) {
_cleanup_free_ char *from = NULL, *to = NULL;
- int r, fd, k;
_cleanup_umask_ mode_t u;
+ int r, fd, k;
union {
struct cmsghdr cmsghdr;
uint8_t buf[CMSG_SPACE(sizeof(int))];
@@ -1401,7 +1480,7 @@ static int setup_kmsg(const char *dest, int kmsg_socket) {
/* Store away the fd in the socket, so that it stays open as
* long as we run the child */
- k = sendmsg(kmsg_socket, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
+ k = sendmsg(kmsg_socket, &mh, MSG_NOSIGNAL);
safe_close(fd);
if (k < 0)
@@ -1412,6 +1491,198 @@ static int setup_kmsg(const char *dest, int kmsg_socket) {
return 0;
}
+static int send_rtnl(int send_fd) {
+ 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;
+ _cleanup_close_ int fd = -1;
+ ssize_t k;
+
+ assert(send_fd >= 0);
+
+ if (!arg_expose_ports)
+ return 0;
+
+ fd = socket(PF_NETLINK, SOCK_RAW|SOCK_CLOEXEC|SOCK_NONBLOCK, NETLINK_ROUTE);
+ if (fd < 0)
+ return log_error_errno(errno, "failed to allocate container netlink: %m");
+
+ 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;
+
+ /* Store away the fd in the socket, so that it stays open as
+ * long as we run the child */
+ k = sendmsg(send_fd, &mh, MSG_NOSIGNAL);
+ if (k < 0)
+ return log_error_errno(errno, "Failed to send netlink fd: %m");
+
+ return 0;
+}
+
+static int flush_ports(union in_addr_union *exposed) {
+ ExposePort *p;
+ int r, af = AF_INET;
+
+ assert(exposed);
+
+ if (!arg_expose_ports)
+ return 0;
+
+ if (in_addr_is_null(af, exposed))
+ return 0;
+
+ log_debug("Lost IP address.");
+
+ LIST_FOREACH(ports, p, arg_expose_ports) {
+ r = fw_add_local_dnat(false,
+ af,
+ p->protocol,
+ NULL,
+ NULL, 0,
+ NULL, 0,
+ p->host_port,
+ exposed,
+ p->container_port,
+ NULL);
+ if (r < 0)
+ log_warning_errno(r, "Failed to modify firewall: %m");
+ }
+
+ *exposed = IN_ADDR_NULL;
+ return 0;
+}
+
+static int expose_ports(sd_rtnl *rtnl, union in_addr_union *exposed) {
+ _cleanup_free_ struct local_address *addresses = NULL;
+ _cleanup_free_ char *pretty = NULL;
+ union in_addr_union new_exposed;
+ ExposePort *p;
+ bool add;
+ int af = AF_INET, r;
+
+ assert(exposed);
+
+ /* Invoked each time an address is added or removed inside the
+ * container */
+
+ if (!arg_expose_ports)
+ return 0;
+
+ r = local_addresses(rtnl, 0, af, &addresses);
+ if (r < 0)
+ return log_error_errno(r, "Failed to enumerate local addresses: %m");
+
+ add = r > 0 &&
+ addresses[0].family == af &&
+ addresses[0].scope < RT_SCOPE_LINK;
+
+ if (!add)
+ return flush_ports(exposed);
+
+ new_exposed = addresses[0].address;
+ if (in_addr_equal(af, exposed, &new_exposed))
+ return 0;
+
+ in_addr_to_string(af, &new_exposed, &pretty);
+ log_debug("New container IP is %s.", strna(pretty));
+
+ LIST_FOREACH(ports, p, arg_expose_ports) {
+
+ r = fw_add_local_dnat(true,
+ af,
+ p->protocol,
+ NULL,
+ NULL, 0,
+ NULL, 0,
+ p->host_port,
+ &new_exposed,
+ p->container_port,
+ in_addr_is_null(af, exposed) ? NULL : exposed);
+ if (r < 0)
+ log_warning_errno(r, "Failed to modify firewall: %m");
+ }
+
+ *exposed = new_exposed;
+ return 0;
+}
+
+static int on_address_change(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
+ union in_addr_union *exposed = userdata;
+
+ assert(rtnl);
+ assert(m);
+ assert(exposed);
+
+ expose_ports(rtnl, exposed);
+ return 0;
+}
+
+static int watch_rtnl(sd_event *event, int recv_fd, union in_addr_union *exposed, sd_rtnl **ret) {
+ 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;
+ _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
+ int fd, r;
+ ssize_t k;
+
+ assert(event);
+ assert(recv_fd >= 0);
+ assert(ret);
+
+ if (!arg_expose_ports)
+ return 0;
+
+ k = recvmsg(recv_fd, &mh, MSG_NOSIGNAL);
+ if (k < 0)
+ return log_error_errno(errno, "Failed to recv netlink fd: %m");
+
+ cmsg = CMSG_FIRSTHDR(&mh);
+ assert(cmsg->cmsg_level == SOL_SOCKET);
+ assert(cmsg->cmsg_type == SCM_RIGHTS);
+ assert(cmsg->cmsg_len = CMSG_LEN(sizeof(int)));
+ memcpy(&fd, CMSG_DATA(cmsg), sizeof(int));
+
+ r = sd_rtnl_open_fd(&rtnl, fd, 1, RTNLGRP_IPV4_IFADDR);
+ if (r < 0) {
+ safe_close(fd);
+ return log_error_errno(r, "Failed to create rtnl object: %m");
+ }
+
+ r = sd_rtnl_add_match(rtnl, RTM_NEWADDR, on_address_change, exposed);
+ if (r < 0)
+ return log_error_errno(r, "Failed to subscribe to RTM_NEWADDR messages: %m");
+
+ r = sd_rtnl_add_match(rtnl, RTM_DELADDR, on_address_change, exposed);
+ if (r < 0)
+ return log_error_errno(r, "Failed to subscribe to RTM_DELADDR messages: %m");
+
+ r = sd_rtnl_attach_event(rtnl, event, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to add to even loop: %m");
+
+ *ret = rtnl;
+ rtnl = NULL;
+
+ return 0;
+}
+
static int setup_hostname(void) {
if (arg_share_system)
@@ -3059,7 +3330,6 @@ int main(int argc, char *argv[]) {
_cleanup_free_ char *device_path = NULL, *root_device = NULL, *home_device = NULL, *srv_device = NULL, *console = NULL;
bool root_device_rw = true, home_device_rw = true, srv_device_rw = true;
_cleanup_close_ int master = -1, image_fd = -1;
- _cleanup_close_pair_ int kmsg_socket_pair[2] = { -1, -1 };
_cleanup_fdset_free_ FDSet *fds = NULL;
int r, n_fd_passed, loop_nr = -1;
char veth_name[IFNAMSIZ];
@@ -3067,6 +3337,7 @@ int main(int argc, char *argv[]) {
sigset_t mask, mask_chld;
pid_t pid = 0;
int ret = EXIT_SUCCESS;
+ union in_addr_union exposed = {};
log_parse_environment();
log_open();
@@ -3233,11 +3504,6 @@ int main(int argc, char *argv[]) {
goto finish;
}
- if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) {
- r = log_error_errno(errno, "Failed to create kmsg socket pair: %m");
- goto finish;
- }
-
assert_se(sigemptyset(&mask) == 0);
sigset_add_many(&mask, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, -1);
assert_se(sigprocmask(SIG_BLOCK, &mask, NULL) == 0);
@@ -3246,6 +3512,7 @@ int main(int argc, char *argv[]) {
assert_se(sigaddset(&mask_chld, SIGCHLD) == 0);
for (;;) {
+ _cleanup_close_pair_ int kmsg_socket_pair[2] = { -1, -1 }, rtnl_socket_pair[2] = { -1, -1 };
ContainerStatus container_status;
_cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL;
struct sigaction sa = {
@@ -3259,6 +3526,16 @@ int main(int argc, char *argv[]) {
goto finish;
}
+ if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) {
+ r = log_error_errno(errno, "Failed to create kmsg socket pair: %m");
+ goto finish;
+ }
+
+ if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0, rtnl_socket_pair) < 0) {
+ r = log_error_errno(errno, "Failed to create rtnl socket pair: %m");
+ goto finish;
+ }
+
/* Child can be killed before execv(), so handle SIGCHLD
* in order to interrupt parent's blocking calls and
* give it a chance to call wait() and terminate. */
@@ -3317,6 +3594,7 @@ int main(int argc, char *argv[]) {
close_nointr(STDERR_FILENO);
kmsg_socket_pair[0] = safe_close(kmsg_socket_pair[0]);
+ rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]);
reset_all_signal_handlers();
reset_signal_mask();
@@ -3412,9 +3690,12 @@ int main(int argc, char *argv[]) {
if (setup_kmsg(arg_directory, kmsg_socket_pair[1]) < 0)
_exit(EXIT_FAILURE);
-
kmsg_socket_pair[1] = safe_close(kmsg_socket_pair[1]);
+ if (send_rtnl(rtnl_socket_pair[1]) < 0)
+ _exit(EXIT_FAILURE);
+ rtnl_socket_pair[1] = safe_close(rtnl_socket_pair[1]);
+
/* Tell the parent that we are ready, and that
* it can cgroupify us to that we lack access
* to certain devices and resources. */
@@ -3585,13 +3866,13 @@ int main(int argc, char *argv[]) {
fdset_free(fds);
fds = NULL;
+ kmsg_socket_pair[1] = safe_close(kmsg_socket_pair[1]);
+ rtnl_socket_pair[1] = safe_close(rtnl_socket_pair[1]);
+
/* Wait for the most basic Child-setup to be done,
* before we add hardware to it, and place it in a
* cgroup. */
if (barrier_sync_next(&barrier)) {
- _cleanup_event_unref_ sd_event *event = NULL;
- _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
- char last_char = 0;
int ifi = 0;
r = move_network_interfaces(pid);
@@ -3631,52 +3912,67 @@ int main(int argc, char *argv[]) {
(void) barrier_place(&barrier);
/* And wait that the child is completely ready now. */
- (void) barrier_place_and_sync(&barrier);
+ if (barrier_place_and_sync(&barrier)) {
+ _cleanup_event_unref_ sd_event *event = NULL;
+ _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
+ _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
+ char last_char = 0;
- sd_notify(false,
- "READY=1\n"
- "STATUS=Container running.");
+ sd_notify(false,
+ "READY=1\n"
+ "STATUS=Container running.");
- r = sd_event_new(&event);
- if (r < 0) {
- log_error_errno(r, "Failed to get default event source: %m");
- goto finish;
- }
+ r = sd_event_new(&event);
+ if (r < 0) {
+ log_error_errno(r, "Failed to get default event source: %m");
+ goto finish;
+ }
- if (arg_boot) {
- /* Try to kill the init system on SIGINT or SIGTERM */
- sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, UINT32_TO_PTR(pid));
- sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, UINT32_TO_PTR(pid));
- } else {
- /* Immediately exit */
- sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
- sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL);
- }
+ if (arg_boot) {
+ /* Try to kill the init system on SIGINT or SIGTERM */
+ sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, UINT32_TO_PTR(pid));
+ sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, UINT32_TO_PTR(pid));
+ } else {
+ /* Immediately exit */
+ sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
+ sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL);
+ }
- /* simply exit on sigchld */
- sd_event_add_signal(event, NULL, SIGCHLD, NULL, NULL);
+ /* simply exit on sigchld */
+ sd_event_add_signal(event, NULL, SIGCHLD, NULL, NULL);
- r = pty_forward_new(event, master, true, &forward);
- if (r < 0) {
- log_error_errno(r, "Failed to create PTY forwarder: %m");
- goto finish;
- }
+ if (arg_expose_ports) {
+ r = watch_rtnl(event, rtnl_socket_pair[0], &exposed, &rtnl);
+ if (r < 0)
+ goto finish;
- r = sd_event_loop(event);
- if (r < 0) {
- log_error_errno(r, "Failed to run event loop: %m");
- goto finish;
- }
+ (void) expose_ports(rtnl, &exposed);
+ }
- pty_forward_get_last_char(forward, &last_char);
+ rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]);
- forward = pty_forward_free(forward);
+ r = pty_forward_new(event, master, true, &forward);
+ if (r < 0) {
+ log_error_errno(r, "Failed to create PTY forwarder: %m");
+ goto finish;
+ }
- if (!arg_quiet && last_char != '\n')
- putc('\n', stdout);
+ r = sd_event_loop(event);
+ if (r < 0) {
+ log_error_errno(r, "Failed to run event loop: %m");
+ goto finish;
+ }
+
+ pty_forward_get_last_char(forward, &last_char);
+
+ forward = pty_forward_free(forward);
+
+ if (!arg_quiet && last_char != '\n')
+ putc('\n', stdout);
- /* Kill if it is not dead yet anyway */
- terminate_machine(pid);
+ /* Kill if it is not dead yet anyway */
+ terminate_machine(pid);
+ }
}
/* Normally redundant, but better safe than sorry */
@@ -3714,6 +4010,8 @@ int main(int argc, char *argv[]) {
r = 0;
break;
}
+
+ flush_ports(&exposed);
}
finish:
@@ -3753,5 +4051,13 @@ finish:
strv_free(arg_bind_ro);
strv_free(arg_tmpfs);
+ flush_ports(&exposed);
+
+ while (arg_expose_ports) {
+ ExposePort *p = arg_expose_ports;
+ LIST_REMOVE(ports, arg_expose_ports, p);
+ free(p);
+ }
+
return r < 0 ? EXIT_FAILURE : ret;
}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-08 11:47:51 +0000