src/basic/cap-list.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright 2014 Lennart Poettering
   4 ***/
   5
   6 #include <errno.h>
   7 #include <string.h>
   8
   9 #include "alloc-util.h"
  10 #include "capability-util.h"
  11 #include "cap-list.h"
  12 #include "extract-word.h"
  13 #include "macro.h"
  14 #include "missing.h"
  15 #include "parse-util.h"
  16 #include "util.h"
  17
  18 static const struct capability_name* lookup_capability(register const char *str, register GPERF_LEN_TYPE len);
  19
  20 #include "cap-from-name.h"
  21 #include "cap-to-name.h"
  22
  23 const char *capability_to_name(int id) {
  24
  25         if (id < 0)
  26                 return NULL;
  27
  28         if (id >= (int) ELEMENTSOF(capability_names))
  29                 return NULL;
  30
  31         return capability_names[id];
  32 }
  33
  34 int capability_from_name(const char *name) {
  35         const struct capability_name *sc;
  36         int r, i;
  37
  38         assert(name);
  39
  40         /* Try to parse numeric capability */
  41         r = safe_atoi(name, &i);
  42         if (r >= 0) {
  43                 if (i >= 0 && i < (int) ELEMENTSOF(capability_names))
  44                         return i;
  45                 else
  46                         return -EINVAL;
  47         }
  48
  49         /* Try to parse string capability */
  50         sc = lookup_capability(name, strlen(name));
  51         if (!sc)
  52                 return -EINVAL;
  53
  54         return sc->id;
  55 }
  56
  57 int capability_list_length(void) {
  58         return (int) ELEMENTSOF(capability_names);
  59 }
  60
  61 int capability_set_to_string_alloc(uint64_t set, char **s) {
  62         _cleanup_free_ char *str = NULL;
  63         unsigned long i;
  64         size_t allocated = 0, n = 0;
  65
  66         assert(s);
  67
  68         for (i = 0; i < cap_last_cap(); i++)
  69                 if (set & (UINT64_C(1) << i)) {
  70                         const char *p;
  71                         size_t add;
  72
  73                         p = capability_to_name(i);
  74                         if (!p)
  75                                 return -EINVAL;
  76
  77                         add = strlen(p);
  78
  79                         if (!GREEDY_REALLOC(str, allocated, n + add + 2))
  80                                 return -ENOMEM;
  81
  82                         strcpy(mempcpy(str + n, p, add), " ");
  83                         n += add + 1;
  84                 }
  85
  86         if (!GREEDY_REALLOC(str, allocated, n + 1))
  87                 return -ENOMEM;
  88
  89         str[n > 0 ? n - 1 : 0] = '\0'; /* truncate the last space, if it's there */
  90
  91         *s = TAKE_PTR(str);
  92
  93         return 0;
  94 }
  95
  96 int capability_set_from_string(const char *s, uint64_t *set) {
  97         uint64_t val = 0;
  98         const char *p;
  99
 100         assert(set);
 101
 102         for (p = s;;) {
 103                 _cleanup_free_ char *word = NULL;
 104                 int r;
 105
 106                 r = extract_first_word(&p, &word, NULL, EXTRACT_QUOTES);
 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 }