src/basic/conf-files.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright 2010 Lennart Poettering
   4 ***/
   5
   6 #include <dirent.h>
   7 #include <errno.h>
   8 #include <stdarg.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12
  13 #include "conf-files.h"
  14 #include "def.h"
  15 #include "dirent-util.h"
  16 #include "fd-util.h"
  17 #include "hashmap.h"
  18 #include "log.h"
  19 #include "macro.h"
  20 #include "missing.h"
  21 #include "path-util.h"
  22 #include "set.h"
  23 #include "stat-util.h"
  24 #include "string-util.h"
  25 #include "strv.h"
  26 #include "terminal-util.h"
  27 #include "util.h"
  28
  29 static int files_add(
  30                 Hashmap *h,
  31                 Set *masked,
  32                 const char *suffix,
  33                 const char *root,
  34                 unsigned flags,
  35                 const char *path) {
  36
  37         _cleanup_closedir_ DIR *dir = NULL;
  38         const char *dirpath;
  39         struct dirent *de;
  40         int r;
  41
  42         assert(h);
  43         assert((flags & CONF_FILES_FILTER_MASKED) == 0 || masked);
  44         assert(path);
  45
  46         dirpath = prefix_roota(root, path);
  47
  48         dir = opendir(dirpath);
  49         if (!dir) {
  50                 if (errno == ENOENT)
  51                         return 0;
  52
  53                 return log_debug_errno(errno, "Failed to open directory '%s': %m", dirpath);
  54         }
  55
  56         FOREACH_DIRENT(de, dir, return -errno) {
  57                 struct stat st;
  58                 char *p, *key;
  59
  60                 /* Does this match the suffix? */
  61                 if (suffix && !endswith(de->d_name, suffix))
  62                         continue;
  63
  64                 /* Has this file already been found in an earlier directory? */
  65                 if (hashmap_contains(h, de->d_name)) {
  66                         log_debug("Skipping overridden file '%s/%s'.", dirpath, de->d_name);
  67                         continue;
  68                 }
  69
  70                 /* Has this been masked in an earlier directory? */
  71                 if ((flags & CONF_FILES_FILTER_MASKED) && set_contains(masked, de->d_name)) {
  72                         log_debug("File '%s/%s' is masked by previous entry.", dirpath, de->d_name);
  73                         continue;
  74                 }
  75
  76                 /* Read file metadata if we shall validate the check for file masks, for node types or whether the node is marked executable. */
  77                 if (flags & (CONF_FILES_FILTER_MASKED|CONF_FILES_REGULAR|CONF_FILES_DIRECTORY|CONF_FILES_EXECUTABLE))
  78                         if (fstatat(dirfd(dir), de->d_name, &st, 0) < 0) {
  79                                 log_debug_errno(errno, "Failed to stat '%s/%s', ignoring: %m", dirpath, de->d_name);
  80                                 continue;
  81                         }
  82
  83                 /* Is this a masking entry? */
  84                 if ((flags & CONF_FILES_FILTER_MASKED))
  85                         if (null_or_empty(&st)) {
  86                                 /* Mark this one as masked */
  87                                 r = set_put_strdup(masked, de->d_name);
  88                                 if (r < 0)
  89                                         return r;
  90
  91                                 log_debug("File '%s/%s' is a mask.", dirpath, de->d_name);
  92                                 continue;
  93                         }
  94
  95                 /* Does this node have the right type? */
  96                 if (flags & (CONF_FILES_REGULAR|CONF_FILES_DIRECTORY))
  97                         if (!((flags & CONF_FILES_DIRECTORY) && S_ISDIR(st.st_mode)) &&
  98                             !((flags & CONF_FILES_REGULAR) && S_ISREG(st.st_mode))) {
  99                                 log_debug("Ignoring '%s/%s', as it is not a of the right type.", dirpath, de->d_name);
 100                                 continue;
 101                         }
 102
 103                 /* Does this node have the executable bit set? */
 104                 if (flags & CONF_FILES_EXECUTABLE)
 105                         /* As requested: check if the file is marked exectuable. Note that we don't check access(X_OK)
 106                          * here, as we care about whether the file is marked executable at all, and not whether it is
 107                          * executable for us, because if so, such errors are stuff we should log about. */
 108
 109                         if ((st.st_mode & 0111) == 0) { /* not executable */
 110                                 log_debug("Ignoring '%s/%s', as it is not marked executable.", dirpath, de->d_name);
 111                                 continue;
 112                         }
 113
 114                 if (flags & CONF_FILES_BASENAME) {
 115                         p = strdup(de->d_name);
 116                         if (!p)
 117                                 return -ENOMEM;
 118
 119                         key = p;
 120                 } else {
 121                         p = strjoin(dirpath, "/", de->d_name);
 122                         if (!p)
 123                                 return -ENOMEM;
 124
 125                         key = basename(p);
 126                 }
 127
 128                 r = hashmap_put(h, key, p);
 129                 if (r < 0) {
 130                         free(p);
 131                         return log_debug_errno(r, "Failed to add item to hashmap: %m");
 132                 }
 133
 134                 assert(r > 0);
 135         }
 136
 137         return 0;
 138 }
 139
 140 static int base_cmp(const void *a, const void *b) {
 141         const char *s1, *s2;
 142
 143         s1 = *(char * const *)a;
 144         s2 = *(char * const *)b;
 145         return strcmp(basename(s1), basename(s2));
 146 }
 147
 148 static int conf_files_list_strv_internal(char ***strv, const char *suffix, const char *root, unsigned flags, char **dirs) {
 149         _cleanup_hashmap_free_ Hashmap *fh = NULL;
 150         _cleanup_set_free_free_ Set *masked = NULL;
 151         char **files, **p;
 152         int r;
 153
 154         assert(strv);
 155
 156         /* This alters the dirs string array */
 157         if (!path_strv_resolve_uniq(dirs, root))
 158                 return -ENOMEM;
 159
 160         fh = hashmap_new(&path_hash_ops);
 161         if (!fh)
 162                 return -ENOMEM;
 163
 164         if (flags & CONF_FILES_FILTER_MASKED) {
 165                 masked = set_new(&path_hash_ops);
 166                 if (!masked)
 167                         return -ENOMEM;
 168         }
 169
 170         STRV_FOREACH(p, dirs) {
 171                 r = files_add(fh, masked, suffix, root, flags, *p);
 172                 if (r == -ENOMEM)
 173                         return r;
 174                 if (r < 0)
 175                         log_debug_errno(r, "Failed to search for files in %s, ignoring: %m", *p);
 176         }
 177
 178         files = hashmap_get_strv(fh);
 179         if (!files)
 180                 return -ENOMEM;
 181
 182         qsort_safe(files, hashmap_size(fh), sizeof(char *), base_cmp);
 183         *strv = files;
 184
 185         return 0;
 186 }
 187
 188 int conf_files_insert(char ***strv, const char *root, char **dirs, const char *path) {
 189         /* Insert a path into strv, at the place honouring the usual sorting rules:
 190          * - we first compare by the basename
 191          * - and then we compare by dirname, allowing just one file with the given
 192          *   basename.
 193          * This means that we will
 194          * - add a new entry if basename(path) was not on the list,
 195          * - do nothing if an entry with higher priority was already present,
 196          * - do nothing if our new entry matches the existing entry,
 197          * - replace the existing entry if our new entry has higher priority.
 198          */
 199         size_t i;
 200         char *t;
 201         int r;
 202
 203         for (i = 0; i < strv_length(*strv); i++) {
 204                 int c;
 205
 206                 c = base_cmp(*strv + i, &path);
 207                 if (c == 0) {
 208                         char **dir;
 209
 210                         /* Oh, we found our spot and it already contains something. */
 211                         STRV_FOREACH(dir, dirs) {
 212                                 char *p1, *p2;
 213
 214                                 p1 = path_startswith((*strv)[i], root);
 215                                 if (p1)
 216                                         /* Skip "/" in *dir, because p1 is without "/" too */
 217                                         p1 = path_startswith(p1, *dir + 1);
 218                                 if (p1)
 219                                         /* Existing entry with higher priority
 220                                          * or same priority, no need to do anything. */
 221                                         return 0;
 222
 223                                 p2 = path_startswith(path, *dir);
 224                                 if (p2) {
 225                                         /* Our new entry has higher priority */
 226                                         t = path_join(root, path, NULL);
 227                                         if (!t)
 228                                                 return log_oom();
 229
 230                                         return free_and_replace((*strv)[i], t);
 231                                 }
 232                         }
 233
 234                 } else if (c > 0)
 235                         /* Following files have lower priority, let's go insert our
 236                          * new entry. */
 237                         break;
 238
 239                 /* … we are not there yet, let's continue */
 240         }
 241
 242         t = path_join(root, path, NULL);
 243         if (!t)
 244                 return log_oom();
 245
 246         r = strv_insert(strv, i, t);
 247         if (r < 0)
 248                 free(t);
 249         return r;
 250 }
 251
 252 int conf_files_insert_nulstr(char ***strv, const char *root, const char *dirs, const char *path) {
 253         _cleanup_strv_free_ char **d = NULL;
 254
 255         assert(strv);
 256
 257         d = strv_split_nulstr(dirs);
 258         if (!d)
 259                 return -ENOMEM;
 260
 261         return conf_files_insert(strv, root, d, path);
 262 }
 263
 264 int conf_files_list_strv(char ***strv, const char *suffix, const char *root, unsigned flags, const char* const* dirs) {
 265         _cleanup_strv_free_ char **copy = NULL;
 266
 267         assert(strv);
 268
 269         copy = strv_copy((char**) dirs);
 270         if (!copy)
 271                 return -ENOMEM;
 272
 273         return conf_files_list_strv_internal(strv, suffix, root, flags, copy);
 274 }
 275
 276 int conf_files_list(char ***strv, const char *suffix, const char *root, unsigned flags, const char *dir, ...) {
 277         _cleanup_strv_free_ char **dirs = NULL;
 278         va_list ap;
 279
 280         assert(strv);
 281
 282         va_start(ap, dir);
 283         dirs = strv_new_ap(dir, ap);
 284         va_end(ap);
 285
 286         if (!dirs)
 287                 return -ENOMEM;
 288
 289         return conf_files_list_strv_internal(strv, suffix, root, flags, dirs);
 290 }
 291
 292 int conf_files_list_nulstr(char ***strv, const char *suffix, const char *root, unsigned flags, const char *dirs) {
 293         _cleanup_strv_free_ char **d = NULL;
 294
 295         assert(strv);
 296
 297         d = strv_split_nulstr(dirs);
 298         if (!d)
 299                 return -ENOMEM;
 300
 301         return conf_files_list_strv_internal(strv, suffix, root, flags, d);
 302 }
 303
 304 int conf_files_list_with_replacement(
 305                 const char *root,
 306                 char **config_dirs,
 307                 const char *replacement,
 308                 char ***files,
 309                 char **replace_file) {
 310
 311         _cleanup_strv_free_ char **f = NULL;
 312         _cleanup_free_ char *p = NULL;
 313         int r;
 314
 315         assert(config_dirs);
 316         assert(files);
 317         assert(replace_file || !replacement);
 318
 319         r = conf_files_list_strv(&f, ".conf", root, 0, (const char* const*) config_dirs);
 320         if (r < 0)
 321                 return log_error_errno(r, "Failed to enumerate config files: %m");
 322
 323         if (replacement) {
 324                 r = conf_files_insert(&f, root, config_dirs, replacement);
 325                 if (r < 0)
 326                         return log_error_errno(r, "Failed to extend config file list: %m");
 327
 328                 p = path_join(root, replacement, NULL);
 329                 if (!p)
 330                         return log_oom();
 331         }
 332
 333         *files = TAKE_PTR(f);
 334         if (replace_file)
 335                 *replace_file = TAKE_PTR(p);
 336         return 0;
 337 }
 338
 339 int conf_files_cat(const char *root, const char *name) {
 340         _cleanup_strv_free_ char **dirs = NULL, **files = NULL;
 341         _cleanup_free_ char *path = NULL;
 342         const char *dir;
 343         char **t;
 344         int r;
 345
 346         NULSTR_FOREACH(dir, CONF_PATHS_NULSTR("")) {
 347                 assert(endswith(dir, "/"));
 348                 r = strv_extendf(&dirs, "%s%s.d", dir, name);
 349                 if (r < 0)
 350                         return log_error_errno(r, "Failed to build directory list: %m");
 351         }
 352
 353         r = conf_files_list_strv(&files, ".conf", root, 0, (const char* const*) dirs);
 354         if (r < 0)
 355                 return log_error_errno(r, "Failed to query file list: %m");
 356
 357         path = path_join(root, "/etc", name);
 358         if (!path)
 359                 return log_oom();
 360
 361         if (DEBUG_LOGGING) {
 362                 log_debug("Looking for configuration in:");
 363                 log_debug("   %s", path);
 364                 STRV_FOREACH(t, dirs)
 365                         log_debug("   %s/*.conf", *t);
 366         }
 367
 368         /* show */
 369         return cat_files(path, files, CAT_FLAGS_MAIN_FILE_OPTIONAL);
 370 }