1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2
3 #include <errno.h>
4 #include <fnmatch.h>
5 #include <getopt.h>
6 #include <stdio.h>
7 #include <stdlib.h>
8
9 #include "sd-hwdb.h"
10
11 #include "alloc-util.h"
12 #include "device-util.h"
13 #include "hwdb-util.h"
14 #include "parse-util.h"
15 #include "string-util.h"
16 #include "udev-builtin.h"
17
18 static sd_hwdb *hwdb;
19
udev_builtin_hwdb_lookup(sd_device * dev,const char * prefix,const char * modalias,const char * filter,bool test)20 int udev_builtin_hwdb_lookup(sd_device *dev,
21 const char *prefix, const char *modalias,
22 const char *filter, bool test) {
23 _cleanup_free_ char *lookup = NULL;
24 const char *key, *value;
25 int n = 0, r;
26
27 if (!hwdb)
28 return -ENOENT;
29
30 if (prefix) {
31 lookup = strjoin(prefix, modalias);
32 if (!lookup)
33 return -ENOMEM;
34 modalias = lookup;
35 }
36
37 SD_HWDB_FOREACH_PROPERTY(hwdb, modalias, key, value) {
38 if (filter && fnmatch(filter, key, FNM_NOESCAPE) != 0)
39 continue;
40
41 r = udev_builtin_add_property(dev, test, key, value);
42 if (r < 0)
43 return r;
44 n++;
45 }
46 return n;
47 }
48
modalias_usb(sd_device * dev,char * s,size_t size)49 static const char *modalias_usb(sd_device *dev, char *s, size_t size) {
50 const char *v, *p, *n = NULL;
51 uint16_t vn, pn;
52
53 if (sd_device_get_sysattr_value(dev, "idVendor", &v) < 0)
54 return NULL;
55 if (sd_device_get_sysattr_value(dev, "idProduct", &p) < 0)
56 return NULL;
57 if (safe_atoux16(v, &vn) < 0)
58 return NULL;
59 if (safe_atoux16(p, &pn) < 0)
60 return NULL;
61 (void) sd_device_get_sysattr_value(dev, "product", &n);
62
63 (void) snprintf(s, size, "usb:v%04Xp%04X:%s", vn, pn, strempty(n));
64 return s;
65 }
66
udev_builtin_hwdb_search(sd_device * dev,sd_device * srcdev,const char * subsystem,const char * prefix,const char * filter,bool test)67 static int udev_builtin_hwdb_search(sd_device *dev, sd_device *srcdev,
68 const char *subsystem, const char *prefix,
69 const char *filter, bool test) {
70 char s[LINE_MAX];
71 bool last = false;
72 int r = 0;
73
74 assert(dev);
75
76 if (!srcdev)
77 srcdev = dev;
78
79 for (sd_device *d = srcdev; d; ) {
80 const char *dsubsys, *devtype, *modalias = NULL;
81
82 if (sd_device_get_subsystem(d, &dsubsys) < 0)
83 goto next;
84
85 /* look only at devices of a specific subsystem */
86 if (subsystem && !streq(dsubsys, subsystem))
87 goto next;
88
89 (void) sd_device_get_property_value(d, "MODALIAS", &modalias);
90
91 if (streq(dsubsys, "usb") &&
92 sd_device_get_devtype(d, &devtype) >= 0 &&
93 streq(devtype, "usb_device")) {
94 /* if the usb_device does not have a modalias, compose one */
95 if (!modalias)
96 modalias = modalias_usb(d, s, sizeof(s));
97
98 /* avoid looking at any parent device, they are usually just a USB hub */
99 last = true;
100 }
101
102 if (!modalias)
103 goto next;
104
105 log_device_debug(dev, "hwdb modalias key: \"%s\"", modalias);
106
107 r = udev_builtin_hwdb_lookup(dev, prefix, modalias, filter, test);
108 if (r > 0)
109 break;
110
111 if (last)
112 break;
113 next:
114 if (sd_device_get_parent(d, &d) < 0)
115 break;
116 }
117
118 return r;
119 }
120
builtin_hwdb(sd_device * dev,sd_netlink ** rtnl,int argc,char * argv[],bool test)121 static int builtin_hwdb(sd_device *dev, sd_netlink **rtnl, int argc, char *argv[], bool test) {
122 static const struct option options[] = {
123 { "filter", required_argument, NULL, 'f' },
124 { "device", required_argument, NULL, 'd' },
125 { "subsystem", required_argument, NULL, 's' },
126 { "lookup-prefix", required_argument, NULL, 'p' },
127 {}
128 };
129 const char *filter = NULL;
130 const char *device = NULL;
131 const char *subsystem = NULL;
132 const char *prefix = NULL;
133 _cleanup_(sd_device_unrefp) sd_device *srcdev = NULL;
134 int r;
135
136 if (!hwdb)
137 return -EINVAL;
138
139 for (;;) {
140 int option;
141
142 option = getopt_long(argc, argv, "f:d:s:p:", options, NULL);
143 if (option == -1)
144 break;
145
146 switch (option) {
147 case 'f':
148 filter = optarg;
149 break;
150
151 case 'd':
152 device = optarg;
153 break;
154
155 case 's':
156 subsystem = optarg;
157 break;
158
159 case 'p':
160 prefix = optarg;
161 break;
162 }
163 }
164
165 /* query a specific key given as argument */
166 if (argv[optind]) {
167 r = udev_builtin_hwdb_lookup(dev, prefix, argv[optind], filter, test);
168 if (r < 0)
169 return log_device_debug_errno(dev, r, "Failed to look up hwdb: %m");
170 if (r == 0)
171 return log_device_debug_errno(dev, SYNTHETIC_ERRNO(ENODATA), "No entry found from hwdb.");
172 return r;
173 }
174
175 /* read data from another device than the device we will store the data */
176 if (device) {
177 r = sd_device_new_from_device_id(&srcdev, device);
178 if (r < 0)
179 return log_device_debug_errno(dev, r, "Failed to create sd_device object '%s': %m", device);
180 }
181
182 r = udev_builtin_hwdb_search(dev, srcdev, subsystem, prefix, filter, test);
183 if (r < 0)
184 return log_device_debug_errno(dev, r, "Failed to look up hwdb: %m");
185 if (r == 0)
186 return log_device_debug_errno(dev, SYNTHETIC_ERRNO(ENODATA), "No entry found from hwdb.");
187 return r;
188 }
189
190 /* called at udev startup and reload */
builtin_hwdb_init(void)191 static int builtin_hwdb_init(void) {
192 int r;
193
194 if (hwdb)
195 return 0;
196
197 r = sd_hwdb_new(&hwdb);
198 if (r < 0)
199 return r;
200
201 return 0;
202 }
203
204 /* called on udev shutdown and reload request */
builtin_hwdb_exit(void)205 static void builtin_hwdb_exit(void) {
206 hwdb = sd_hwdb_unref(hwdb);
207 }
208
209 /* called every couple of seconds during event activity; 'true' if config has changed */
builtin_hwdb_validate(void)210 static bool builtin_hwdb_validate(void) {
211 return hwdb_validate(hwdb);
212 }
213
214 const UdevBuiltin udev_builtin_hwdb = {
215 .name = "hwdb",
216 .cmd = builtin_hwdb,
217 .init = builtin_hwdb_init,
218 .exit = builtin_hwdb_exit,
219 .validate = builtin_hwdb_validate,
220 .help = "Hardware database",
221 };
222