src/basic/cap-list.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2014 Lennart Poettering
   6 ***/
   7
   8 #include <errno.h>
   9 #include <string.h>
  10
  11 #include "alloc-util.h"
  12 #include "capability-util.h"
  13 #include "cap-list.h"
  14 #include "extract-word.h"
  15 #include "macro.h"
  16 #include "missing.h"
  17 #include "parse-util.h"
  18 #include "util.h"
  19
  20 static const struct capability_name* lookup_capability(register const char *str, register GPERF_LEN_TYPE len);
  21
  22 #include "cap-from-name.h"
  23 #include "cap-to-name.h"
  24
  25 const char *capability_to_name(int id) {
  26
  27         if (id < 0)
  28                 return NULL;
  29
  30         if (id >= (int) ELEMENTSOF(capability_names))
  31                 return NULL;
  32
  33         return capability_names[id];
  34 }
  35
  36 int capability_from_name(const char *name) {
  37         const struct capability_name *sc;
  38         int r, i;
  39
  40         assert(name);
  41
  42         /* Try to parse numeric capability */
  43         r = safe_atoi(name, &i);
  44         if (r >= 0) {
  45                 if (i >= 0 && i < (int) ELEMENTSOF(capability_names))
  46                         return i;
  47                 else
  48                         return -EINVAL;
  49         }
  50
  51         /* Try to parse string capability */
  52         sc = lookup_capability(name, strlen(name));
  53         if (!sc)
  54                 return -EINVAL;
  55
  56         return sc->id;
  57 }
  58
  59 int capability_list_length(void) {
  60         return (int) ELEMENTSOF(capability_names);
  61 }
  62
  63 int capability_set_to_string_alloc(uint64_t set, char **s) {
  64         _cleanup_free_ char *str = NULL;
  65         unsigned long i;
  66         size_t allocated = 0, n = 0;
  67
  68         assert(s);
  69
  70         for (i = 0; i < cap_last_cap(); i++)
  71                 if (set & (UINT64_C(1) << i)) {
  72                         const char *p;
  73                         size_t add;
  74
  75                         p = capability_to_name(i);
  76                         if (!p)
  77                                 return -EINVAL;
  78
  79                         add = strlen(p);
  80
  81                         if (!GREEDY_REALLOC(str, allocated, n + add + 2))
  82                                 return -ENOMEM;
  83
  84                         strcpy(mempcpy(str + n, p, add), " ");
  85                         n += add + 1;
  86                 }
  87
  88         if (!GREEDY_REALLOC(str, allocated, n + 1))
  89                 return -ENOMEM;
  90
  91         str[n > 0 ? n - 1 : 0] = '\0'; /* truncate the last space, if it's there */
  92
  93         *s = TAKE_PTR(str);
  94
  95         return 0;
  96 }
  97
  98 int capability_set_from_string(const char *s, uint64_t *set) {
  99         uint64_t val = 0;
 100         const char *p;
 101
 102         assert(set);
 103
 104         for (p = s;;) {
 105                 _cleanup_free_ char *word = NULL;
 106                 int r;
 107
 108                 r = extract_first_word(&p, &word, NULL, EXTRACT_QUOTES);
 109                 if (r == -ENOMEM)
 110                         return r;
 111                 if (r <= 0)
 112                         break;
 113
 114                 r = capability_from_name(word);
 115                 if (r < 0)
 116                         continue;
 117
 118                 val |= ((uint64_t) UINT64_C(1)) << (uint64_t) r;
 119         }
 120
 121         *set = val;
 122
 123         return 0;
 124 }