src/basic/cap-list.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   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
  20 const char *capability_to_name(int id) {
  21
  22         if (id < 0)
  23                 return NULL;
  24
  25         if ((size_t) id >= ELEMENTSOF(capability_names))
  26                 return NULL;
  27
  28         return capability_names[id];
  29 }
  30
  31 int capability_from_name(const char *name) {
  32         const struct capability_name *sc;
  33         int r, i;
  34
  35         assert(name);
  36
  37         /* Try to parse numeric capability */
  38         r = safe_atoi(name, &i);
  39         if (r >= 0) {
  40                 if (i >= 0 && i < 64)
  41                         return i;
  42                 else
  43                         return -EINVAL;
  44         }
  45
  46         /* Try to parse string capability */
  47         sc = lookup_capability(name, strlen(name));
  48         if (!sc)
  49                 return -EINVAL;
  50
  51         return sc->id;
  52 }
  53
  54 int capability_list_length(void) {
  55         return (int) ELEMENTSOF(capability_names);
  56 }
  57
  58 int capability_set_to_string_alloc(uint64_t set, char **s) {
  59         _cleanup_free_ char *str = NULL;
  60         size_t allocated = 0, n = 0;
  61
  62         assert(s);
  63
  64         for (unsigned i = 0; i <= cap_last_cap(); i++)
  65                 if (set & (UINT64_C(1) << i)) {
  66                         const char *p;
  67                         char buf[2 + 16 + 1];
  68                         size_t add;
  69
  70                         p = capability_to_name(i);
  71                         if (!p) {
  72                                 xsprintf(buf, "0x%x", i);
  73                                 p = buf;
  74                         }
  75
  76                         add = strlen(p);
  77
  78                         if (!GREEDY_REALLOC(str, allocated, n + add + 2))
  79                                 return -ENOMEM;
  80
  81                         strcpy(mempcpy(str + n, p, add), " ");
  82                         n += add + 1;
  83                 }
  84
  85         if (!GREEDY_REALLOC(str, allocated, n + 1))
  86                 return -ENOMEM;
  87
  88         str[n > 0 ? n - 1 : 0] = '\0'; /* truncate the last space, if it's there */
  89
  90         *s = TAKE_PTR(str);
  91
  92         return 0;
  93 }
  94
  95 int capability_set_from_string(const char *s, uint64_t *set) {
  96         uint64_t val = 0;
  97         const char *p;
  98
  99         assert(set);
 100
 101         for (p = s;;) {
 102                 _cleanup_free_ char *word = NULL;
 103                 int r;
 104
 105                 r = extract_first_word(&p, &word, NULL, EXTRACT_UNQUOTE);
 106                 if (r == -ENOMEM)
 107                         return r;
 108                 if (r <= 0)
 109                         break;
 110
 111                 r = capability_from_name(word);
 112                 if (r < 0)
 113                         continue;
 114
 115                 val |= ((uint64_t) UINT64_C(1)) << (uint64_t) r;
 116         }
 117
 118         *set = val;
 119
 120         return 0;
 121 }