1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 
3 #include <errno.h>
4 #include <getopt.h>
5 #include <stdbool.h>
6 #include <stddef.h>
7 
8 #include "env-util.h"
9 #include "log.h"
10 #include "macro.h"
11 #include "process-util.h"
12 #include "string-util.h"
13 #include "verbs.h"
14 #include "virt.h"
15 
16 /* Wraps running_in_chroot() which is used in various places, but also adds an environment variable check so external
17  * processes can reliably force this on.
18  */
running_in_chroot_or_offline(void)19 bool running_in_chroot_or_offline(void) {
20         int r;
21 
22         /* Added to support use cases like rpm-ostree, where from %post scripts we only want to execute "preset", but
23          * not "start"/"restart" for example.
24          *
25          * See docs/ENVIRONMENT.md for docs.
26          */
27         r = getenv_bool("SYSTEMD_OFFLINE");
28         if (r < 0 && r != -ENXIO)
29                 log_debug_errno(r, "Failed to parse $SYSTEMD_OFFLINE: %m");
30         else if (r >= 0)
31                 return r > 0;
32 
33         /* We've had this condition check for a long time which basically checks for legacy chroot case like Fedora's
34          * "mock", which is used for package builds.  We don't want to try to start systemd services there, since
35          * without --new-chroot we don't even have systemd running, and even if we did, adding a concept of background
36          * daemons to builds would be an enormous change, requiring considering things like how the journal output is
37          * handled, etc.  And there's really not a use case today for a build talking to a service.
38          *
39          * Note this call itself also looks for a different variable SYSTEMD_IGNORE_CHROOT=1.
40          */
41         r = running_in_chroot();
42         if (r < 0)
43                 log_debug_errno(r, "running_in_chroot(): %m");
44 
45         return r > 0;
46 }
47 
verbs_find_verb(const char * name,const Verb verbs[])48 const Verb* verbs_find_verb(const char *name, const Verb verbs[]) {
49         for (size_t i = 0; verbs[i].dispatch; i++)
50                 if (streq_ptr(name, verbs[i].verb) ||
51                     (!name && FLAGS_SET(verbs[i].flags, VERB_DEFAULT)))
52                         return &verbs[i];
53 
54         /* At the end of the list? */
55         return NULL;
56 }
57 
dispatch_verb(int argc,char * argv[],const Verb verbs[],void * userdata)58 int dispatch_verb(int argc, char *argv[], const Verb verbs[], void *userdata) {
59         const Verb *verb;
60         const char *name;
61         int left;
62 
63         assert(verbs);
64         assert(verbs[0].dispatch);
65         assert(argc >= 0);
66         assert(argv);
67         assert(argc >= optind);
68 
69         left = argc - optind;
70         argv += optind;
71         optind = 0;
72         name = argv[0];
73 
74         verb = verbs_find_verb(name, verbs);
75         if (!verb) {
76                 if (name)
77                         return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
78                                                "Unknown command verb %s.", name);
79                 else
80                         return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
81                                                "Command verb required.");
82         }
83 
84         if (!name)
85                 left = 1;
86 
87         if (verb->min_args != VERB_ANY &&
88             (unsigned) left < verb->min_args)
89                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
90                                        "Too few arguments.");
91 
92         if (verb->max_args != VERB_ANY &&
93             (unsigned) left > verb->max_args)
94                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
95                                        "Too many arguments.");
96 
97         if ((verb->flags & VERB_ONLINE_ONLY) && running_in_chroot_or_offline()) {
98                 log_info("Running in chroot, ignoring command '%s'", name ?: verb->verb);
99                 return 0;
100         }
101 
102         if (name)
103                 return verb->dispatch(left, argv, userdata);
104         else {
105                 char* fake[2] = {
106                         (char*) verb->verb,
107                         NULL
108                 };
109 
110                 return verb->dispatch(1, fake, userdata);
111         }
112 }
113