1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 
3 #include <errno.h>
4 #include <string.h>
5 
6 #include "alloc-util.h"
7 #include "capability-util.h"
8 #include "cap-list.h"
9 #include "extract-word.h"
10 #include "macro.h"
11 #include "parse-util.h"
12 #include "stdio-util.h"
13 #include "util.h"
14 
15 static const struct capability_name* lookup_capability(register const char *str, register GPERF_LEN_TYPE len);
16 
17 #include "cap-from-name.h"
18 #include "cap-to-name.h"
19 
capability_to_name(int id)20 const char *capability_to_name(int id) {
21         if (id < 0)
22                 return NULL;
23 
24         if ((size_t) id >= ELEMENTSOF(capability_names))
25                 return NULL;
26 
27         return capability_names[id];
28 }
29 
capability_from_name(const char * name)30 int capability_from_name(const char *name) {
31         const struct capability_name *sc;
32         int r, i;
33 
34         assert(name);
35 
36         /* Try to parse numeric capability */
37         r = safe_atoi(name, &i);
38         if (r >= 0) {
39                 if (i >= 0 && i < 64)
40                         return i;
41                 else
42                         return -EINVAL;
43         }
44 
45         /* Try to parse string capability */
46         sc = lookup_capability(name, strlen(name));
47         if (!sc)
48                 return -EINVAL;
49 
50         return sc->id;
51 }
52 
53 /* This is the number of capability names we are *compiled* with.
54  * For the max capability number of the currently-running kernel,
55  * use cap_last_cap(). */
capability_list_length(void)56 int capability_list_length(void) {
57         return (int) ELEMENTSOF(capability_names);
58 }
59 
capability_set_to_string_alloc(uint64_t set,char ** s)60 int capability_set_to_string_alloc(uint64_t set, char **s) {
61         _cleanup_free_ char *str = NULL;
62         size_t n = 0;
63 
64         assert(s);
65 
66         for (unsigned i = 0; i <= cap_last_cap(); i++)
67                 if (set & (UINT64_C(1) << i)) {
68                         const char *p;
69                         char buf[2 + 16 + 1];
70                         size_t add;
71 
72                         p = capability_to_name(i);
73                         if (!p) {
74                                 xsprintf(buf, "0x%x", i);
75                                 p = buf;
76                         }
77 
78                         add = strlen(p);
79 
80                         if (!GREEDY_REALLOC(str, n + add + 2))
81                                 return -ENOMEM;
82 
83                         strcpy(mempcpy(str + n, p, add), " ");
84                         n += add + 1;
85                 }
86 
87         if (!GREEDY_REALLOC(str, n + 1))
88                 return -ENOMEM;
89 
90         str[n > 0 ? n - 1 : 0] = '\0'; /* truncate the last space, if it's there */
91 
92         *s = TAKE_PTR(str);
93 
94         return 0;
95 }
96 
capability_set_from_string(const char * s,uint64_t * set)97 int capability_set_from_string(const char *s, uint64_t *set) {
98         uint64_t val = 0;
99 
100         assert(set);
101 
102         for (const char *p = s;;) {
103                 _cleanup_free_ char *word = NULL;
104                 int r;
105 
106                 r = extract_first_word(&p, &word, NULL, EXTRACT_UNQUOTE);
107                 if (r == -ENOMEM)
108                         return r;
109                 if (r <= 0)
110                         break;
111 
112                 r = capability_from_name(word);
113                 if (r < 0)
114                         continue;
115 
116                 val |= ((uint64_t) UINT64_C(1)) << (uint64_t) r;
117         }
118 
119         *set = val;
120 
121         return 0;
122 }
123