15336122756

Committed 29 May 2025 09:26PM UTC coverage: 72.064% (+0.02%) from 72.04%

Build # 15336122756

Build Type

push

github

Committed by

yuwata

Commit Message

NEWS: fix typos

Coverage Stats

299688 of 415863 relevant lines covered (72.06%)

699722.54 hits per line

Source File
Press 'n' to go to next uncovered line, 'b' for previous

0.0

/src/ssh-generator/ssh-generator.c

/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include <unistd.h>

#include "alloc-util.h"
#include "creds-util.h"
#include "errno-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "generator.h"
#include "install.h"
#include "log.h"
#include "missing_socket.h"
#include "parse-util.h"
#include "path-lookup.h"
#include "path-util.h"
#include "proc-cmdline.h"
#include "socket-netlink.h"
#include "socket-util.h"
#include "special.h"
#include "string-util.h"
#include "strv.h"
#include "virt.h"

/* A small generator binding potentially five or more SSH sockets:
 *
 *     1. Listen on AF_VSOCK port 22 if we run in a VM with AF_VSOCK enabled
 *     2. Listen on AF_UNIX socket /run/host/unix-export/ssh if we run in a container with /run/host/ support
 *     3. Listen on AF_UNIX socket /run/ssh-unix-local/socket (always)
 *     4. Listen on any socket specified via kernel command line option systemd.ssh_listen=
 *     5. Similar, but from system credential ssh.listen
 *
 * The first two provide a nice way for hosts to connect to containers and VMs they invoke via the usual SSH
 * logic, but without waiting for networking or suchlike. The third allows the same for local clients. */

static const char *arg_dest = NULL;
static bool arg_auto = true;
static char **arg_listen_extra = NULL;

static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
        int r;

        assert(key);

        if (proc_cmdline_key_streq(key, "systemd.ssh_auto")) {
                r = value ? parse_boolean(value) : 1;
                if (r < 0)
                        log_warning_errno(r, "Failed to parse systemd.ssh_auto switch \"%s\", ignoring: %m", value);
                else
                        arg_auto = r;

        } else if (proc_cmdline_key_streq(key, "systemd.ssh_listen")) {

                if (proc_cmdline_value_missing(key, value))
                        return 0;

                SocketAddress sa;
                r = socket_address_parse(&sa, value);
                if (r < 0)
                        log_warning_errno(r, "Failed to parse systemd.ssh_listen= expression, ignoring: %s", value);
                else {
                        _cleanup_free_ char *s = NULL;
                        r = socket_address_print(&sa, &s);
                        if (r < 0)
                                return log_error_errno(r, "Failed to format socket address: %m");

                        if (strv_consume(&arg_listen_extra, TAKE_PTR(s)) < 0)
                                return log_oom();
                }
        }

        return 0;
}

static int make_sshd_template_unit(
                const char *dest,
                const char *template,
                const char *sshd_binary,
                const char *found_sshd_template_service,
                char **generated_sshd_template_unit) {

        int r;

        assert(dest);
        assert(template);
        assert(sshd_binary);
        assert(generated_sshd_template_unit);

        /* If the system has a suitable template already, symlink it to the name we want to reuse it */
        if (found_sshd_template_service)
                return generator_add_symlink(
                                dest,
                                template,
                                /* dep_type= */ NULL,
                                found_sshd_template_service);

        if (!*generated_sshd_template_unit) {
                _cleanup_fclose_ FILE *f = NULL;

                r = generator_open_unit_file_full(
                                dest,
                                /* source= */ NULL,
                                "sshd-generated@.service", /* Give this generated unit a generic name, since we want to use it for both AF_UNIX and AF_VSOCK */
                                &f,
                                generated_sshd_template_unit,
                                /* ret_temp_path= */ NULL);
                if (r < 0)
                        return r;

                fprintf(f,
                        "[Unit]\n"
                        "Description=OpenSSH Per-Connection Server Daemon\n"
                        "Documentation=man:systemd-ssh-generator(8) man:sshd(8)\n"
                        "\n"
                        "[Service]\n"
                        "ExecStart=-%s -i -o \"AuthorizedKeysFile ${CREDENTIALS_DIRECTORY}/ssh.ephemeral-authorized_keys-all .ssh/authorized_keys\"\n"
                        "StandardInput=socket\n"
                        "ImportCredential=ssh.ephemeral-authorized_keys-all\n",
                        sshd_binary);

                r = fflush_and_check(f);
                if (r < 0)
                        return log_error_errno(r, "Failed to write sshd template: %m");
        }

        return generator_add_symlink(
                        dest,
                        template,
                        /* dep_type= */ NULL,
                        *generated_sshd_template_unit);
}

static int write_socket_unit(
                const char *dest,
                const char *unit,
                const char *listen_stream,
                const char *comment,
                bool with_ssh_access_target_dependency) {

        int r;

        assert(dest);
        assert(unit);
        assert(listen_stream);
        assert(comment);

        _cleanup_fclose_ FILE *f = NULL;
        r = generator_open_unit_file(
                        dest,
                        /* source= */ NULL,
                        unit,
                        &f);
        if (r < 0)
                return r;

        fprintf(f,
                "[Unit]\n"
                "Description=OpenSSH Server Socket (systemd-ssh-generator, %s)\n"
                "Documentation=man:systemd-ssh-generator(8)\n",
                comment);

        /* When this is a remotely accessible socket let's mark this with a milestone: ssh-access.target */
        if (with_ssh_access_target_dependency)
                fputs("Wants=ssh-access.target\n"
                      "Before=ssh-access.target\n",
                      f);

        fprintf(f,
                "\n[Socket]\n"
                "ListenStream=%s\n"
                "Accept=yes\n"
                "PollLimitIntervalSec=30s\n"
                "PollLimitBurst=50\n",
                listen_stream);

        r = fflush_and_check(f);
        if (r < 0)
                return log_error_errno(r, "Failed to write %s SSH socket unit: %m", comment);

        r = generator_add_symlink(
                        dest,
                        SPECIAL_SOCKETS_TARGET,
                        "wants",
                        unit);
        if (r < 0)
                return r;

        return 0;
}

static int add_vsock_socket(
                const char *dest,
                const char *sshd_binary,
                const char *found_sshd_template_unit,
                char **generated_sshd_template_unit) {

        int r;

        assert(dest);
        assert(generated_sshd_template_unit);

        Virtualization v = detect_virtualization();
        if (v < 0)
                return log_error_errno(v, "Failed to detect if we run in a VM: %m");
        if (!VIRTUALIZATION_IS_VM(v)) {
                /* NB: if we are running in a container inside a VM, then we'll *not* do AF_VSOCK stuff */
                log_debug("Not running in a VM, not listening on AF_VSOCK.");
                return 0;
        }

        _cleanup_close_ int vsock_fd = socket(AF_VSOCK, SOCK_STREAM|SOCK_CLOEXEC, 0);
        if (vsock_fd < 0) {
                if (ERRNO_IS_NOT_SUPPORTED(errno)) {
                        log_debug("Not creating AF_VSOCK ssh listener, since AF_VSOCK is not available.");
                        return 0;
                }

                return log_error_errno(errno, "Unable to test if AF_VSOCK is available: %m");
        }

        vsock_fd = safe_close(vsock_fd);

        /* Determine the local CID so that we can log it to help users to connect to this VM */
        unsigned local_cid;
        r = vsock_get_local_cid(&local_cid);
        if (r < 0) {
                if (ERRNO_IS_DEVICE_ABSENT(r)) {
                        log_debug("Not creating AF_VSOCK ssh listener, since /dev/vsock is not available (even though AF_VSOCK is).");
                        return 0;
                }

                return log_error_errno(r, "Failed to query local AF_VSOCK CID: %m");
        }

        r = make_sshd_template_unit(
                        dest,
                        "sshd-vsock@.service",
                        sshd_binary,
                        found_sshd_template_unit,
                        generated_sshd_template_unit);
        if (r < 0)
                return r;

        r = write_socket_unit(
                        dest,
                        "sshd-vsock.socket",
                        "vsock::22",
                        "AF_VSOCK",
                        /* with_ssh_access_target_dependency= */ true);
        if (r < 0)
                return r;

        log_debug("Binding SSH to AF_VSOCK vsock::22.\n"
                  "→ connect via 'ssh vsock/%u' from host", local_cid);
        return 0;
}

static int add_local_unix_socket(
                const char *dest,
                const char *sshd_binary,
                const char *found_sshd_template_unit,
                char **generated_sshd_template_unit) {

        int r;

        assert(dest);
        assert(sshd_binary);
        assert(generated_sshd_template_unit);

        r = make_sshd_template_unit(
                        dest,
                        "sshd-unix-local@.service",
                        sshd_binary,
                        found_sshd_template_unit,
                        generated_sshd_template_unit);
        if (r < 0)
                return r;

        r = write_socket_unit(
                        dest,
                        "sshd-unix-local.socket",
                        "/run/ssh-unix-local/socket",
                        "AF_UNIX Local",
                        /* with_ssh_access_target_dependency= */ false);
        if (r < 0)
                return r;

        log_debug("Binding SSH to AF_UNIX socket /run/ssh-unix-local/socket.\n"
                  "→ connect via 'ssh .host' locally");
        return 0;
}

static int add_export_unix_socket(
                const char *dest,
                const char *sshd_binary,
                const char *found_sshd_template_unit,
                char **generated_sshd_template_unit) {

        int r;

        assert(dest);
        assert(sshd_binary);
        assert(generated_sshd_template_unit);

        Virtualization v = detect_container();
        if (v < 0)
                return log_error_errno(v, "Failed to detect if we run in a container: %m");
        if (v == VIRTUALIZATION_NONE) {
                log_debug("Not running in container, not listening on /run/host/unix-export/ssh");
                return 0;
        }

        if (access("/run/host/unix-export/", W_OK) < 0) {
                if (errno == ENOENT) {
                        log_debug("Container manager does not provide /run/host/unix-export/ mount, not binding AF_UNIX socket there.");
                        return 0;
                }
                if (errno == EROFS || ERRNO_IS_PRIVILEGE(errno)) {
                        log_debug("Container manager does not provide write access to /run/host/unix-export/, not binding AF_UNIX socket there.");
                        return 0;
                }

                return log_error_errno(errno, "Unable to check if /run/host/unix-export exists: %m");
        }

        r = make_sshd_template_unit(
                        dest,
                        "sshd-unix-export@.service",
                        sshd_binary,
                        found_sshd_template_unit,
                        generated_sshd_template_unit);
        if (r < 0)
                return r;

        r = write_socket_unit(
                        dest,
                        "sshd-unix-export.socket",
                        "/run/host/unix-export/ssh",
                        "AF_UNIX Export",
                        /* with_ssh_access_target_dependency= */ true);
        if (r < 0)
                return r;

        log_debug("Binding SSH to AF_UNIX socket /run/host/unix-export/ssh\n"
                  "→ connect via 'ssh unix/run/systemd/nspawn/unix-export/\?\?\?/ssh' from host");

        return 0;
}

static int add_extra_sockets(
                const char *dest,
                const char *sshd_binary,
                const char *found_sshd_template_unit,
                char **generated_sshd_template_unit) {

        unsigned n = 1;
        int r;

        assert(dest);
        assert(sshd_binary);
        assert(generated_sshd_template_unit);

        if (strv_isempty(arg_listen_extra))
                return 0;

        STRV_FOREACH(i, arg_listen_extra) {
                _cleanup_free_ char *service = NULL, *socket = NULL;

                if (n > 1) {
                        if (asprintf(&service, "sshd-extra-%u@.service", n) < 0)
                                return log_oom();

                        if (asprintf(&socket, "sshd-extra-%u.socket", n) < 0)
                                return log_oom();
                }

                r = make_sshd_template_unit(
                                dest,
                                service ?: "sshd-extra@.service",
                                sshd_binary,
                                found_sshd_template_unit,
                                generated_sshd_template_unit);
                if (r < 0)
                        return r;

                r = write_socket_unit(
                                dest,
                                socket ?: "sshd-extra.socket",
                                *i,
                                *i,
                                /* with_ssh_access_target_dependency= */ true);
                if (r < 0)
                        return r;

                log_debug("Binding SSH to socket %s.", *i);
                n++;
        }

        return 0;
}

static int parse_credentials(void) {
        _cleanup_free_ char *b = NULL;
        size_t sz = 0;
        int r;

        r = read_credential_with_decryption("ssh.listen", (void**) &b, &sz);
        if (r <= 0)
                return r;

        _cleanup_fclose_ FILE *f = NULL;
        f = fmemopen_unlocked(b, sz, "r");
        if (!f)
                return log_oom();

        for (;;) {
                _cleanup_free_ char *item = NULL;

                r = read_stripped_line(f, LINE_MAX, &item);
                if (r == 0)
                        break;
                if (r < 0) {
                        log_error_errno(r, "Failed to parse credential 'ssh.listen': %m");
                        break;
                }

                if (startswith(item, "#"))
                        continue;

                SocketAddress sa;
                r = socket_address_parse(&sa, item);
                if (r < 0) {
                        log_warning_errno(r, "Failed to parse systemd.ssh_listen= expression, ignoring: %s", item);
                        continue;
                }

                _cleanup_free_ char *s = NULL;
                r = socket_address_print(&sa, &s);
                if (r < 0)
                        return log_error_errno(r, "Failed to format socket address: %m");

                if (strv_consume(&arg_listen_extra, TAKE_PTR(s)) < 0)
                        return log_oom();
        }

        return 0;
}

static int run(const char *dest, const char *dest_early, const char *dest_late) {
        int r;

        assert_se(arg_dest = dest);

        r = proc_cmdline_parse(parse_proc_cmdline_item, /* userdata= */ NULL, /* flags= */ 0);
        if (r < 0)
                log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");

        (void) parse_credentials();

        strv_sort_uniq(arg_listen_extra);

        if (!arg_auto && strv_isempty(arg_listen_extra)) {
                log_debug("Disabling SSH generator logic, because it has been turned off explicitly.");
                return 0;
        }

        _cleanup_free_ char *sshd_binary = NULL;
        r = find_executable("sshd", &sshd_binary);
        if (r == -ENOENT) {
                log_debug("Disabling SSH generator logic, since sshd is not installed.");
                return 0;
        }
        if (r < 0)
                return log_error_errno(r, "Failed to determine if sshd is installed: %m");

        _cleanup_(lookup_paths_done) LookupPaths lp = {};
        r = lookup_paths_init_or_warn(&lp, RUNTIME_SCOPE_SYSTEM, LOOKUP_PATHS_EXCLUDE_GENERATED, /* root_dir= */ NULL);
        if (r < 0)
                return r;

        _cleanup_free_ char *found_sshd_template_unit = NULL;
        r = unit_file_exists_full(RUNTIME_SCOPE_SYSTEM, &lp, "sshd@.service", &found_sshd_template_unit);
        if (r < 0)
                return log_error_errno(r, "Unable to detect if sshd@.service exists: %m");

        _cleanup_free_ char *generated_sshd_template_unit = NULL;
        RET_GATHER(r, add_extra_sockets(dest, sshd_binary, found_sshd_template_unit, &generated_sshd_template_unit));

        if (arg_auto) {
                RET_GATHER(r, add_vsock_socket(dest, sshd_binary, found_sshd_template_unit, &generated_sshd_template_unit));
                RET_GATHER(r, add_local_unix_socket(dest, sshd_binary, found_sshd_template_unit, &generated_sshd_template_unit));
                RET_GATHER(r, add_export_unix_socket(dest, sshd_binary, found_sshd_template_unit, &generated_sshd_template_unit));
        }

        return r;
}

DEFINE_MAIN_GENERATOR_FUNCTION(run);

1	/* SPDX-License-Identifier: LGPL-2.1-or-later */
2
3	#include <unistd.h>
4
5	#include "alloc-util.h"
6	#include "creds-util.h"
7	#include "errno-util.h"
8	#include "fd-util.h"
9	#include "fileio.h"
10	#include "generator.h"
11	#include "install.h"
12	#include "log.h"
13	#include "missing_socket.h"
14	#include "parse-util.h"
15	#include "path-lookup.h"
16	#include "path-util.h"
17	#include "proc-cmdline.h"
18	#include "socket-netlink.h"
19	#include "socket-util.h"
20	#include "special.h"
21	#include "string-util.h"
22	#include "strv.h"
23	#include "virt.h"
24
25	/* A small generator binding potentially five or more SSH sockets:
26	*
27	* 1. Listen on AF_VSOCK port 22 if we run in a VM with AF_VSOCK enabled
28	* 2. Listen on AF_UNIX socket /run/host/unix-export/ssh if we run in a container with /run/host/ support
29	* 3. Listen on AF_UNIX socket /run/ssh-unix-local/socket (always)
30	* 4. Listen on any socket specified via kernel command line option systemd.ssh_listen=
31	* 5. Similar, but from system credential ssh.listen
32	*
33	* The first two provide a nice way for hosts to connect to containers and VMs they invoke via the usual SSH
34	* logic, but without waiting for networking or suchlike. The third allows the same for local clients. */
35
36	static const char *arg_dest = NULL;
37	static bool arg_auto = true;
38	static char **arg_listen_extra = NULL;
39
40	static int parse_proc_cmdline_item(const char key, const char value, void *data) {	×
41	int r;	×
42
43	assert(key);	×
44
45	if (proc_cmdline_key_streq(key, "systemd.ssh_auto")) {	×
46	r = value ? parse_boolean(value) : 1;	×
47	if (r < 0)	×
48	log_warning_errno(r, "Failed to parse systemd.ssh_auto switch \"%s\", ignoring: %m", value);	×
49	else
50	arg_auto = r;	×
51
52	} else if (proc_cmdline_key_streq(key, "systemd.ssh_listen")) {	×
53
54	if (proc_cmdline_value_missing(key, value))	×
55	return 0;	×
56
57	SocketAddress sa;	×
58	r = socket_address_parse(&sa, value);	×
59	if (r < 0)	×
60	log_warning_errno(r, "Failed to parse systemd.ssh_listen= expression, ignoring: %s", value);	×
61	else {
62	_cleanup_free_ char *s = NULL;	×
63	r = socket_address_print(&sa, &s);	×
64	if (r < 0)	×
65	return log_error_errno(r, "Failed to format socket address: %m");	×
66
67	if (strv_consume(&arg_listen_extra, TAKE_PTR(s)) < 0)	×
68	return log_oom();	×
69	}
70	}
71
72	return 0;
73	}
74
75	static int make_sshd_template_unit(	×
76	const char *dest,
77	const char *template,
78	const char *sshd_binary,
79	const char *found_sshd_template_service,
80	char **generated_sshd_template_unit) {
81
82	int r;	×
83
84	assert(dest);	×
85	assert(template);	×
86	assert(sshd_binary);	×
87	assert(generated_sshd_template_unit);	×
88
89	/* If the system has a suitable template already, symlink it to the name we want to reuse it */
90	if (found_sshd_template_service)	×
91	return generator_add_symlink(	×
92	dest,
93	template,
94	/* dep_type= */ NULL,
95	found_sshd_template_service);
96
97	if (!*generated_sshd_template_unit) {	×
98	_cleanup_fclose_ FILE *f = NULL;	×
99
100	r = generator_open_unit_file_full(	×
101	dest,
102	/* source= */ NULL,
103	"sshd-generated@.service", /* Give this generated unit a generic name, since we want to use it for both AF_UNIX and AF_VSOCK */
104	&f,
105	generated_sshd_template_unit,
106	/* ret_temp_path= */ NULL);
107	if (r < 0)	×
108	return r;
109
110	fprintf(f,	×
111	"[Unit]\n"
112	"Description=OpenSSH Per-Connection Server Daemon\n"
113	"Documentation=man:systemd-ssh-generator(8) man:sshd(8)\n"
114	"\n"
115	"[Service]\n"
116	"ExecStart=-%s -i -o \"AuthorizedKeysFile ${CREDENTIALS_DIRECTORY}/ssh.ephemeral-authorized_keys-all .ssh/authorized_keys\"\n"
117	"StandardInput=socket\n"
118	"ImportCredential=ssh.ephemeral-authorized_keys-all\n",
119	sshd_binary);
120
121	r = fflush_and_check(f);	×
122	if (r < 0)	×
123	return log_error_errno(r, "Failed to write sshd template: %m");	×
124	}
125
126	return generator_add_symlink(	×
127	dest,
128	template,
129	/* dep_type= */ NULL,
130	*generated_sshd_template_unit);
131	}
132
133	static int write_socket_unit(	×
134	const char *dest,
135	const char *unit,
136	const char *listen_stream,
137	const char *comment,
138	bool with_ssh_access_target_dependency) {
139
140	int r;	×
141
142	assert(dest);	×
143	assert(unit);	×
144	assert(listen_stream);	×
145	assert(comment);	×
146
147	_cleanup_fclose_ FILE *f = NULL;	×
148	r = generator_open_unit_file(	×
149	dest,
150	/* source= */ NULL,
151	unit,
152	&f);
153	if (r < 0)	×
154	return r;
155
156	fprintf(f,	×
157	"[Unit]\n"
158	"Description=OpenSSH Server Socket (systemd-ssh-generator, %s)\n"
159	"Documentation=man:systemd-ssh-generator(8)\n",
160	comment);
161
162	/* When this is a remotely accessible socket let's mark this with a milestone: ssh-access.target */
163	if (with_ssh_access_target_dependency)	×
164	fputs("Wants=ssh-access.target\n"	×
165	"Before=ssh-access.target\n",
166	f);
167
168	fprintf(f,	×
169	"\n[Socket]\n"
170	"ListenStream=%s\n"
171	"Accept=yes\n"
172	"PollLimitIntervalSec=30s\n"
173	"PollLimitBurst=50\n",
174	listen_stream);
175
176	r = fflush_and_check(f);	×
177	if (r < 0)	×
178	return log_error_errno(r, "Failed to write %s SSH socket unit: %m", comment);	×
179
180	r = generator_add_symlink(	×
181	dest,
182	SPECIAL_SOCKETS_TARGET,
183	"wants",
184	unit);
185	if (r < 0)	×
186	return r;	×
187
188	return 0;
189	}
190
191	static int add_vsock_socket(	×
192	const char *dest,
193	const char *sshd_binary,
194	const char *found_sshd_template_unit,
195	char **generated_sshd_template_unit) {
196
197	int r;	×
198
199	assert(dest);	×
200	assert(generated_sshd_template_unit);	×
201
202	Virtualization v = detect_virtualization();	×
203	if (v < 0)	×
204	return log_error_errno(v, "Failed to detect if we run in a VM: %m");	×
205	if (!VIRTUALIZATION_IS_VM(v)) {	×
206	/* NB: if we are running in a container inside a VM, then we'll not do AF_VSOCK stuff */
207	log_debug("Not running in a VM, not listening on AF_VSOCK.");	×
208	return 0;	×
209	}
210
211	_cleanup_close_ int vsock_fd = socket(AF_VSOCK, SOCK_STREAM\|SOCK_CLOEXEC, 0);	×
212	if (vsock_fd < 0) {	×
213	if (ERRNO_IS_NOT_SUPPORTED(errno)) {	×
214	log_debug("Not creating AF_VSOCK ssh listener, since AF_VSOCK is not available.");	×
215	return 0;	×
216	}
217
218	return log_error_errno(errno, "Unable to test if AF_VSOCK is available: %m");	×
219	}
220
221	vsock_fd = safe_close(vsock_fd);	×
222
223	/* Determine the local CID so that we can log it to help users to connect to this VM */
224	unsigned local_cid;	×
225	r = vsock_get_local_cid(&local_cid);	×
226	if (r < 0) {	×
227	if (ERRNO_IS_DEVICE_ABSENT(r)) {	×
228	log_debug("Not creating AF_VSOCK ssh listener, since /dev/vsock is not available (even though AF_VSOCK is).");	×
229	return 0;	×
230	}
231
232	return log_error_errno(r, "Failed to query local AF_VSOCK CID: %m");	×
233	}
234
235	r = make_sshd_template_unit(	×
236	dest,
237	"sshd-vsock@.service",
238	sshd_binary,
239	found_sshd_template_unit,
240	generated_sshd_template_unit);
241	if (r < 0)	×
242	return r;
243
244	r = write_socket_unit(	×
245	dest,
246	"sshd-vsock.socket",
247	"vsock::22",
248	"AF_VSOCK",
249	/* with_ssh_access_target_dependency= */ true);
250	if (r < 0)	×
251	return r;
252
253	log_debug("Binding SSH to AF_VSOCK vsock::22.\n"	×
254	"→ connect via 'ssh vsock/%u' from host", local_cid);
255	return 0;
256	}
257
258	static int add_local_unix_socket(	×
259	const char *dest,
260	const char *sshd_binary,
261	const char *found_sshd_template_unit,
262	char **generated_sshd_template_unit) {
263
264	int r;	×
265
266	assert(dest);	×
267	assert(sshd_binary);	×
268	assert(generated_sshd_template_unit);	×
269
270	r = make_sshd_template_unit(	×
271	dest,
272	"sshd-unix-local@.service",
273	sshd_binary,
274	found_sshd_template_unit,
275	generated_sshd_template_unit);
276	if (r < 0)	×
277	return r;
278
279	r = write_socket_unit(	×
280	dest,
281	"sshd-unix-local.socket",
282	"/run/ssh-unix-local/socket",
283	"AF_UNIX Local",
284	/* with_ssh_access_target_dependency= */ false);
285	if (r < 0)	×
286	return r;
287
288	log_debug("Binding SSH to AF_UNIX socket /run/ssh-unix-local/socket.\n"	×
289	"→ connect via 'ssh .host' locally");
290	return 0;
291	}
292
293	static int add_export_unix_socket(	×
294	const char *dest,
295	const char *sshd_binary,
296	const char *found_sshd_template_unit,
297	char **generated_sshd_template_unit) {
298
299	int r;	×
300
301	assert(dest);	×
302	assert(sshd_binary);	×
303	assert(generated_sshd_template_unit);	×
304
305	Virtualization v = detect_container();	×
306	if (v < 0)	×
307	return log_error_errno(v, "Failed to detect if we run in a container: %m");	×
308	if (v == VIRTUALIZATION_NONE) {	×
309	log_debug("Not running in container, not listening on /run/host/unix-export/ssh");	×
310	return 0;	×
311	}
312
313	if (access("/run/host/unix-export/", W_OK) < 0) {	×
314	if (errno == ENOENT) {	×
315	log_debug("Container manager does not provide /run/host/unix-export/ mount, not binding AF_UNIX socket there.");	×
316	return 0;	×
317	}
318	if (errno == EROFS \|\| ERRNO_IS_PRIVILEGE(errno)) {	×
319	log_debug("Container manager does not provide write access to /run/host/unix-export/, not binding AF_UNIX socket there.");	×
320	return 0;	×
321	}
322
323	return log_error_errno(errno, "Unable to check if /run/host/unix-export exists: %m");	×
324	}
325
326	r = make_sshd_template_unit(	×
327	dest,
328	"sshd-unix-export@.service",
329	sshd_binary,
330	found_sshd_template_unit,
331	generated_sshd_template_unit);
332	if (r < 0)	×
333	return r;
334
335	r = write_socket_unit(	×
336	dest,
337	"sshd-unix-export.socket",
338	"/run/host/unix-export/ssh",
339	"AF_UNIX Export",
340	/* with_ssh_access_target_dependency= */ true);
341	if (r < 0)	×
342	return r;
343
344	log_debug("Binding SSH to AF_UNIX socket /run/host/unix-export/ssh\n"	×
345	"→ connect via 'ssh unix/run/systemd/nspawn/unix-export/\?\?\?/ssh' from host");
346
347	return 0;
348	}
349
350	static int add_extra_sockets(	×
351	const char *dest,
352	const char *sshd_binary,
353	const char *found_sshd_template_unit,
354	char **generated_sshd_template_unit) {
355
356	unsigned n = 1;	×
357	int r;	×
358
359	assert(dest);	×
360	assert(sshd_binary);	×
361	assert(generated_sshd_template_unit);	×
362
363	if (strv_isempty(arg_listen_extra))	×
364	return 0;
365
366	STRV_FOREACH(i, arg_listen_extra) {	×
367	_cleanup_free_ char service = NULL, socket = NULL;	×
368
369	if (n > 1) {	×
370	if (asprintf(&service, "sshd-extra-%u@.service", n) < 0)	×
371	return log_oom();	×
372
373	if (asprintf(&socket, "sshd-extra-%u.socket", n) < 0)	×
374	return log_oom();	×
375	}
376
377	r = make_sshd_template_unit(	×
378	dest,
379	service ?: "sshd-extra@.service",	×
380	sshd_binary,
381	found_sshd_template_unit,
382	generated_sshd_template_unit);
383	if (r < 0)	×
384	return r;
385
386	r = write_socket_unit(	×
387	dest,
388	socket ?: "sshd-extra.socket",	×
389	*i,
390	*i,
391	/* with_ssh_access_target_dependency= */ true);
392	if (r < 0)	×
393	return r;
394
395	log_debug("Binding SSH to socket %s.", *i);	×
396	n++;	×
397	}
398
399	return 0;
400	}
401
402	static int parse_credentials(void) {	×
403	_cleanup_free_ char *b = NULL;	×
404	size_t sz = 0;	×
405	int r;	×
406
407	r = read_credential_with_decryption("ssh.listen", (void**) &b, &sz);	×
408	if (r <= 0)	×
409	return r;
410
411	_cleanup_fclose_ FILE *f = NULL;	×
412	f = fmemopen_unlocked(b, sz, "r");	×
413	if (!f)	×
414	return log_oom();	×
415
416	for (;;) {	×
417	_cleanup_free_ char *item = NULL;	×
418
419	r = read_stripped_line(f, LINE_MAX, &item);	×
420	if (r == 0)	×
421	break;
422	if (r < 0) {	×
423	log_error_errno(r, "Failed to parse credential 'ssh.listen': %m");	×
424	break;
425	}
426
427	if (startswith(item, "#"))	×
428	continue;	×
429
430	SocketAddress sa;	×
431	r = socket_address_parse(&sa, item);	×
432	if (r < 0) {	×
433	log_warning_errno(r, "Failed to parse systemd.ssh_listen= expression, ignoring: %s", item);	×
434	continue;	×
435	}
436
437	_cleanup_free_ char *s = NULL;	×
438	r = socket_address_print(&sa, &s);	×
439	if (r < 0)	×
440	return log_error_errno(r, "Failed to format socket address: %m");	×
441
442	if (strv_consume(&arg_listen_extra, TAKE_PTR(s)) < 0)	×
443	return log_oom();	×
444	}
445
446	return 0;	×
447	}
448
449	static int run(const char dest, const char dest_early, const char *dest_late) {	×
450	int r;	×
451
452	assert_se(arg_dest = dest);	×
453
454	r = proc_cmdline_parse(parse_proc_cmdline_item, /* userdata= / NULL, / flags= */ 0);	×
455	if (r < 0)	×
456	log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");	×
457
458	(void) parse_credentials();	×
459
460	strv_sort_uniq(arg_listen_extra);	×
461
462	if (!arg_auto && strv_isempty(arg_listen_extra)) {	×
463	log_debug("Disabling SSH generator logic, because it has been turned off explicitly.");	×
464	return 0;	×
465	}
466
467	_cleanup_free_ char *sshd_binary = NULL;	×
468	r = find_executable("sshd", &sshd_binary);	×
469	if (r == -ENOENT) {	×
470	log_debug("Disabling SSH generator logic, since sshd is not installed.");	×
471	return 0;	×
472	}
473	if (r < 0)	×
474	return log_error_errno(r, "Failed to determine if sshd is installed: %m");	×
475
476	_cleanup_(lookup_paths_done) LookupPaths lp = {};	×
477	r = lookup_paths_init_or_warn(&lp, RUNTIME_SCOPE_SYSTEM, LOOKUP_PATHS_EXCLUDE_GENERATED, /* root_dir= */ NULL);	×
478	if (r < 0)	×
479	return r;
480
481	_cleanup_free_ char *found_sshd_template_unit = NULL;	×
482	r = unit_file_exists_full(RUNTIME_SCOPE_SYSTEM, &lp, "sshd@.service", &found_sshd_template_unit);	×
483	if (r < 0)	×
484	return log_error_errno(r, "Unable to detect if sshd@.service exists: %m");	×
485
486	_cleanup_free_ char *generated_sshd_template_unit = NULL;	×
487	RET_GATHER(r, add_extra_sockets(dest, sshd_binary, found_sshd_template_unit, &generated_sshd_template_unit));	×
488
489	if (arg_auto) {	×
490	RET_GATHER(r, add_vsock_socket(dest, sshd_binary, found_sshd_template_unit, &generated_sshd_template_unit));	×
491	RET_GATHER(r, add_local_unix_socket(dest, sshd_binary, found_sshd_template_unit, &generated_sshd_template_unit));	×
492	RET_GATHER(r, add_export_unix_socket(dest, sshd_binary, found_sshd_template_unit, &generated_sshd_template_unit));	×
493	}
494
495	return r;	×
496	}
497
498	DEFINE_MAIN_GENERATOR_FUNCTION(run);	×

systemd / systemd / 15336122756

Source File Press 'n' to go to next uncovered line, 'b' for previous

Source File
Press 'n' to go to next uncovered line, 'b' for previous