src/libsystemd/sd-hwdb/hwdb-util.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <ctype.h>
   4 #include <stdio.h>
   5
   6 #include "alloc-util.h"
   7 #include "conf-files.h"
   8 #include "fd-util.h"
   9 #include "fileio.h"
  10 #include "fs-util.h"
  11 #include "hwdb-internal.h"
  12 #include "hwdb-util.h"
  13 #include "label.h"
  14 #include "mkdir.h"
  15 #include "path-util.h"
  16 #include "strbuf.h"
  17 #include "string-util.h"
  18 #include "strv.h"
  19 #include "tmpfile-util.h"
  20
  21 static const char *default_hwdb_bin_dir = "/etc/udev";
  22 static const char * const conf_file_dirs[] = {
  23         "/etc/udev/hwdb.d",
  24         UDEVLIBEXECDIR "/hwdb.d",
  25         NULL
  26 };
  27
  28 /*
  29  * Generic udev properties, key-value database based on modalias strings.
  30  * Uses a Patricia/radix trie to index all matches for efficient lookup.
  31  */
  32
  33 /* in-memory trie objects */
  34 struct trie {
  35         struct trie_node *root;
  36         struct strbuf *strings;
  37
  38         size_t nodes_count;
  39         size_t children_count;
  40         size_t values_count;
  41 };
  42
  43 struct trie_node {
  44         /* prefix, common part for all children of this node */
  45         size_t prefix_off;
  46
  47         /* sorted array of pointers to children nodes */
  48         struct trie_child_entry *children;
  49         uint8_t children_count;
  50
  51         /* sorted array of key-value pairs */
  52         struct trie_value_entry *values;
  53         size_t values_count;
  54 };
  55
  56 /* children array item with char (0-255) index */
  57 struct trie_child_entry {
  58         uint8_t c;
  59         struct trie_node *child;
  60 };
  61
  62 /* value array item with key-value pairs */
  63 struct trie_value_entry {
  64         size_t key_off;
  65         size_t value_off;
  66         size_t filename_off;
  67         uint32_t line_number;
  68         uint16_t file_priority;
  69 };
  70
  71 static int trie_children_cmp(const struct trie_child_entry *a, const struct trie_child_entry *b) {
  72         return CMP(a->c, b->c);
  73 }
  74
  75 static int node_add_child(struct trie *trie, struct trie_node *node, struct trie_node *node_child, uint8_t c) {
  76         struct trie_child_entry *child;
  77
  78         /* extend array, add new entry, sort for bisection */
  79         child = reallocarray(node->children, node->children_count + 1, sizeof(struct trie_child_entry));
  80         if (!child)
  81                 return -ENOMEM;
  82
  83         node->children = child;
  84         trie->children_count++;
  85         node->children[node->children_count].c = c;
  86         node->children[node->children_count].child = node_child;
  87         node->children_count++;
  88         typesafe_qsort(node->children, node->children_count, trie_children_cmp);
  89         trie->nodes_count++;
  90
  91         return 0;
  92 }
  93
  94 static struct trie_node *node_lookup(const struct trie_node *node, uint8_t c) {
  95         struct trie_child_entry *child;
  96         struct trie_child_entry search;
  97
  98         search.c = c;
  99         child = typesafe_bsearch(&search, node->children, node->children_count, trie_children_cmp);
 100         if (child)
 101                 return child->child;
 102         return NULL;
 103 }
 104
 105 static void trie_node_cleanup(struct trie_node *node) {
 106         size_t i;
 107
 108         if (!node)
 109                 return;
 110
 111         for (i = 0; i < node->children_count; i++)
 112                 trie_node_cleanup(node->children[i].child);
 113         free(node->children);
 114         free(node->values);
 115         free(node);
 116 }
 117
 118 static void trie_free(struct trie *trie) {
 119         if (!trie)
 120                 return;
 121
 122         trie_node_cleanup(trie->root);
 123         strbuf_cleanup(trie->strings);
 124         free(trie);
 125 }
 126
 127 DEFINE_TRIVIAL_CLEANUP_FUNC(struct trie*, trie_free);
 128
 129 static int trie_values_cmp(const struct trie_value_entry *a, const struct trie_value_entry *b, struct trie *trie) {
 130         return strcmp(trie->strings->buf + a->key_off,
 131                       trie->strings->buf + b->key_off);
 132 }
 133
 134 static int trie_node_add_value(struct trie *trie, struct trie_node *node,
 135                                const char *key, const char *value,
 136                                const char *filename, uint16_t file_priority, uint32_t line_number, bool compat) {
 137         ssize_t k, v, fn = 0;
 138         struct trie_value_entry *val;
 139
 140         k = strbuf_add_string(trie->strings, key, strlen(key));
 141         if (k < 0)
 142                 return k;
 143         v = strbuf_add_string(trie->strings, value, strlen(value));
 144         if (v < 0)
 145                 return v;
 146
 147         if (!compat) {
 148                 fn = strbuf_add_string(trie->strings, filename, strlen(filename));
 149                 if (fn < 0)
 150                         return fn;
 151         }
 152
 153         if (node->values_count) {
 154                 struct trie_value_entry search = {
 155                         .key_off = k,
 156                         .value_off = v,
 157                 };
 158
 159                 val = typesafe_bsearch_r(&search, node->values, node->values_count, trie_values_cmp, trie);
 160                 if (val) {
 161                         /* At this point we have 2 identical properties on the same match-string.
 162                          * Since we process files in order, we just replace the previous value. */
 163                         val->value_off = v;
 164                         val->filename_off = fn;
 165                         val->file_priority = file_priority;
 166                         val->line_number = line_number;
 167                         return 0;
 168                 }
 169         }
 170
 171         /* extend array, add new entry, sort for bisection */
 172         val = reallocarray(node->values, node->values_count + 1, sizeof(struct trie_value_entry));
 173         if (!val)
 174                 return -ENOMEM;
 175         trie->values_count++;
 176         node->values = val;
 177         node->values[node->values_count] = (struct trie_value_entry) {
 178                 .key_off = k,
 179                 .value_off = v,
 180                 .filename_off = fn,
 181                 .file_priority = file_priority,
 182                 .line_number = line_number,
 183         };
 184         node->values_count++;
 185         typesafe_qsort_r(node->values, node->values_count, trie_values_cmp, trie);
 186         return 0;
 187 }
 188
 189 static int trie_insert(struct trie *trie, struct trie_node *node, const char *search,
 190                        const char *key, const char *value,
 191                        const char *filename, uint16_t file_priority, uint32_t line_number, bool compat) {
 192         size_t i = 0;
 193         int r = 0;
 194
 195         for (;;) {
 196                 size_t p;
 197                 uint8_t c;
 198                 struct trie_node *child;
 199
 200                 for (p = 0; (c = trie->strings->buf[node->prefix_off + p]); p++) {
 201                         _cleanup_free_ struct trie_node *new_child = NULL;
 202                         _cleanup_free_ char *s = NULL;
 203                         ssize_t off;
 204
 205                         if (c == search[i + p])
 206                                 continue;
 207
 208                         /* split node */
 209                         new_child = new(struct trie_node, 1);
 210                         if (!new_child)
 211                                 return -ENOMEM;
 212
 213                         /* move values from parent to child */
 214                         *new_child = (struct trie_node) {
 215                                 .prefix_off = node->prefix_off + p+1,
 216                                 .children = node->children,
 217                                 .children_count = node->children_count,
 218                                 .values = node->values,
 219                                 .values_count = node->values_count,
 220                         };
 221
 222                         /* update parent; use strdup() because the source gets realloc()d */
 223                         s = strndup(trie->strings->buf + node->prefix_off, p);
 224                         if (!s)
 225                                 return -ENOMEM;
 226
 227                         off = strbuf_add_string(trie->strings, s, p);
 228                         if (off < 0)
 229                                 return off;
 230
 231                         *node = (struct trie_node) {
 232                                 .prefix_off = off,
 233                         };
 234                         r = node_add_child(trie, node, new_child, c);
 235                         if (r < 0)
 236                                 return r;
 237
 238                         new_child = NULL; /* avoid cleanup */
 239                         break;
 240                 }
 241                 i += p;
 242
 243                 c = search[i];
 244                 if (c == '\0')
 245                         return trie_node_add_value(trie, node, key, value, filename, file_priority, line_number, compat);
 246
 247                 child = node_lookup(node, c);
 248                 if (!child) {
 249                         _cleanup_free_ struct trie_node *new_child = NULL;
 250                         ssize_t off;
 251
 252                         /* new child */
 253                         new_child = new(struct trie_node, 1);
 254                         if (!new_child)
 255                                 return -ENOMEM;
 256
 257                         off = strbuf_add_string(trie->strings, search + i+1, strlen(search + i+1));
 258                         if (off < 0)
 259                                 return off;
 260
 261                         *new_child = (struct trie_node) {
 262                                 .prefix_off = off,
 263                         };
 264
 265                         r = node_add_child(trie, node, new_child, c);
 266                         if (r < 0)
 267                                 return r;
 268
 269                         child = TAKE_PTR(new_child);
 270                         return trie_node_add_value(trie, child, key, value, filename, file_priority, line_number, compat);
 271                 }
 272
 273                 node = child;
 274                 i++;
 275         }
 276 }
 277
 278 struct trie_f {
 279         FILE *f;
 280         struct trie *trie;
 281         uint64_t strings_off;
 282
 283         uint64_t nodes_count;
 284         uint64_t children_count;
 285         uint64_t values_count;
 286 };
 287
 288 /* calculate the storage space for the nodes, children arrays, value arrays */
 289 static void trie_store_nodes_size(struct trie_f *trie, struct trie_node *node, bool compat) {
 290         uint64_t i;
 291
 292         for (i = 0; i < node->children_count; i++)
 293                 trie_store_nodes_size(trie, node->children[i].child, compat);
 294
 295         trie->strings_off += sizeof(struct trie_node_f);
 296         for (i = 0; i < node->children_count; i++)
 297                 trie->strings_off += sizeof(struct trie_child_entry_f);
 298         for (i = 0; i < node->values_count; i++)
 299                 trie->strings_off += compat ? sizeof(struct trie_value_entry_f) : sizeof(struct trie_value_entry2_f);
 300 }
 301
 302 static int64_t trie_store_nodes(struct trie_f *trie, struct trie_node *node, bool compat) {
 303         uint64_t i;
 304         struct trie_node_f n = {
 305                 .prefix_off = htole64(trie->strings_off + node->prefix_off),
 306                 .children_count = node->children_count,
 307                 .values_count = htole64(node->values_count),
 308         };
 309         _cleanup_free_ struct trie_child_entry_f *children = NULL;
 310         int64_t node_off;
 311
 312         if (node->children_count) {
 313                 children = new(struct trie_child_entry_f, node->children_count);
 314                 if (!children)
 315                         return -ENOMEM;
 316         }
 317
 318         /* post-order recursion */
 319         for (i = 0; i < node->children_count; i++) {
 320                 int64_t child_off;
 321
 322                 child_off = trie_store_nodes(trie, node->children[i].child, compat);
 323                 if (child_off < 0)
 324                         return child_off;
 325
 326                 children[i] = (struct trie_child_entry_f) {
 327                         .c = node->children[i].c,
 328                         .child_off = htole64(child_off),
 329                 };
 330         }
 331
 332         /* write node */
 333         node_off = ftello(trie->f);
 334         fwrite(&n, sizeof(struct trie_node_f), 1, trie->f);
 335         trie->nodes_count++;
 336
 337         /* append children array */
 338         if (node->children_count) {
 339                 fwrite(children, sizeof(struct trie_child_entry_f), node->children_count, trie->f);
 340                 trie->children_count += node->children_count;
 341         }
 342
 343         /* append values array */
 344         for (i = 0; i < node->values_count; i++) {
 345                 struct trie_value_entry2_f v = {
 346                         .key_off = htole64(trie->strings_off + node->values[i].key_off),
 347                         .value_off = htole64(trie->strings_off + node->values[i].value_off),
 348                         .filename_off = htole64(trie->strings_off + node->values[i].filename_off),
 349                         .line_number = htole32(node->values[i].line_number),
 350                         .file_priority = htole16(node->values[i].file_priority),
 351                 };
 352
 353                 fwrite(&v, compat ? sizeof(struct trie_value_entry_f) : sizeof(struct trie_value_entry2_f), 1, trie->f);
 354         }
 355         trie->values_count += node->values_count;
 356
 357         return node_off;
 358 }
 359
 360 static int trie_store(struct trie *trie, const char *filename, bool compat) {
 361         struct trie_f t = {
 362                 .trie = trie,
 363         };
 364         _cleanup_free_ char *filename_tmp = NULL;
 365         int64_t pos;
 366         int64_t root_off;
 367         int64_t size;
 368         struct trie_header_f h = {
 369                 .signature = HWDB_SIG,
 370                 .tool_version = htole64(PROJECT_VERSION),
 371                 .header_size = htole64(sizeof(struct trie_header_f)),
 372                 .node_size = htole64(sizeof(struct trie_node_f)),
 373                 .child_entry_size = htole64(sizeof(struct trie_child_entry_f)),
 374                 .value_entry_size = htole64(compat ? sizeof(struct trie_value_entry_f) : sizeof(struct trie_value_entry2_f)),
 375         };
 376         int r;
 377
 378         /* calculate size of header, nodes, children entries, value entries */
 379         t.strings_off = sizeof(struct trie_header_f);
 380         trie_store_nodes_size(&t, trie->root, compat);
 381
 382         r = fopen_temporary(filename, &t.f, &filename_tmp);
 383         if (r < 0)
 384                 return r;
 385         fchmod(fileno(t.f), 0444);
 386
 387         /* write nodes */
 388         if (fseeko(t.f, sizeof(struct trie_header_f), SEEK_SET) < 0)
 389                 goto error_fclose;
 390
 391         root_off = trie_store_nodes(&t, trie->root, compat);
 392         h.nodes_root_off = htole64(root_off);
 393         pos = ftello(t.f);
 394         h.nodes_len = htole64(pos - sizeof(struct trie_header_f));
 395
 396         /* write string buffer */
 397         fwrite(trie->strings->buf, trie->strings->len, 1, t.f);
 398         h.strings_len = htole64(trie->strings->len);
 399
 400         /* write header */
 401         size = ftello(t.f);
 402         h.file_size = htole64(size);
 403         if (fseeko(t.f, 0, SEEK_SET) < 0)
 404                 goto error_fclose;
 405         fwrite(&h, sizeof(struct trie_header_f), 1, t.f);
 406
 407         if (ferror(t.f))
 408                 goto error_fclose;
 409         if (fflush(t.f) < 0)
 410                 goto error_fclose;
 411         if (fsync(fileno(t.f)) < 0)
 412                 goto error_fclose;
 413         if (rename(filename_tmp, filename) < 0)
 414                 goto error_fclose;
 415
 416         /* write succeeded */
 417         fclose(t.f);
 418
 419         log_debug("=== trie on-disk ===");
 420         log_debug("size:             %8"PRIi64" bytes", size);
 421         log_debug("header:           %8zu bytes", sizeof(struct trie_header_f));
 422         log_debug("nodes:            %8"PRIu64" bytes (%8"PRIu64")",
 423                   t.nodes_count * sizeof(struct trie_node_f), t.nodes_count);
 424         log_debug("child pointers:   %8"PRIu64" bytes (%8"PRIu64")",
 425                   t.children_count * sizeof(struct trie_child_entry_f), t.children_count);
 426         log_debug("value pointers:   %8"PRIu64" bytes (%8"PRIu64")",
 427                   t.values_count * (compat ? sizeof(struct trie_value_entry_f) : sizeof(struct trie_value_entry2_f)), t.values_count);
 428         log_debug("string store:     %8zu bytes", trie->strings->len);
 429         log_debug("strings start:    %8"PRIu64, t.strings_off);
 430         return 0;
 431
 432  error_fclose:
 433         r = -errno;
 434         fclose(t.f);
 435         unlink(filename_tmp);
 436         return r;
 437 }
 438
 439 static int insert_data(struct trie *trie, char **match_list, char *line, const char *filename,
 440                        uint16_t file_priority, uint32_t line_number, bool compat) {
 441         char *value, **entry;
 442
 443         assert(line[0] == ' ');
 444
 445         value = strchr(line, '=');
 446         if (!value)
 447                 return log_syntax(NULL, LOG_WARNING, filename, line_number, EINVAL,
 448                                   "Key-value pair expected but got \"%s\", ignoring", line);
 449
 450         value[0] = '\0';
 451         value++;
 452
 453         /* Replace multiple leading spaces by a single space */
 454         while (isblank(line[0]) && isblank(line[1]))
 455                 line++;
 456
 457         if (isempty(line + 1) || isempty(value))
 458                 return log_syntax(NULL, LOG_WARNING, filename, line_number, EINVAL,
 459                                   "Empty %s in \"%s=%s\", ignoring",
 460                                   isempty(line + 1) ? "key" : "value",
 461                                   line, value);
 462
 463         STRV_FOREACH(entry, match_list)
 464                 trie_insert(trie, trie->root, *entry, line, value, filename, file_priority, line_number, compat);
 465
 466         return 0;
 467 }
 468
 469 static int import_file(struct trie *trie, const char *filename, uint16_t file_priority, bool compat) {
 470         enum {
 471                 HW_NONE,
 472                 HW_MATCH,
 473                 HW_DATA,
 474         } state = HW_NONE;
 475         _cleanup_fclose_ FILE *f = NULL;
 476         _cleanup_strv_free_ char **match_list = NULL;
 477         uint32_t line_number = 0;
 478         char *match = NULL;
 479         int r = 0, err;
 480
 481         f = fopen(filename, "re");
 482         if (!f)
 483                 return -errno;
 484
 485         for (;;) {
 486                 _cleanup_free_ char *line = NULL;
 487                 size_t len;
 488                 char *pos;
 489
 490                 r = read_line(f, LONG_LINE_MAX, &line);
 491                 if (r < 0)
 492                         return r;
 493                 if (r == 0)
 494                         break;
 495
 496                 ++line_number;
 497
 498                 /* comment line */
 499                 if (line[0] == '#')
 500                         continue;
 501
 502                 /* strip trailing comment */
 503                 pos = strchr(line, '#');
 504                 if (pos)
 505                         pos[0] = '\0';
 506
 507                 /* strip trailing whitespace */
 508                 len = strlen(line);
 509                 while (len > 0 && isspace(line[len-1]))
 510                         len--;
 511                 line[len] = '\0';
 512
 513                 switch (state) {
 514                 case HW_NONE:
 515                         if (len == 0)
 516                                 break;
 517
 518                         if (line[0] == ' ') {
 519                                 log_syntax(NULL, LOG_WARNING, filename, line_number, EINVAL,
 520                                            "Match expected but got indented property \"%s\", ignoring line", line);
 521                                 r = -EINVAL;
 522                                 break;
 523                         }
 524
 525                         /* start of record, first match */
 526                         state = HW_MATCH;
 527
 528                         match = strdup(line);
 529                         if (!match)
 530                                 return -ENOMEM;
 531
 532                         err = strv_consume(&match_list, match);
 533                         if (err < 0)
 534                                 return err;
 535
 536                         break;
 537
 538                 case HW_MATCH:
 539                         if (len == 0) {
 540                                 log_syntax(NULL, LOG_WARNING, filename, line_number, EINVAL,
 541                                            "Property expected, ignoring record with no properties");
 542                                 r = -EINVAL;
 543                                 state = HW_NONE;
 544                                 strv_clear(match_list);
 545                                 break;
 546                         }
 547
 548                         if (line[0] != ' ') {
 549                                 /* another match */
 550                                 match = strdup(line);
 551                                 if (!match)
 552                                         return -ENOMEM;
 553
 554                                 err = strv_consume(&match_list, match);
 555                                 if (err < 0)
 556                                         return err;
 557
 558                                 break;
 559                         }
 560
 561                         /* first data */
 562                         state = HW_DATA;
 563                         err = insert_data(trie, match_list, line, filename, file_priority, line_number, compat);
 564                         if (err < 0)
 565                                 r = err;
 566                         break;
 567
 568                 case HW_DATA:
 569                         if (len == 0) {
 570                                 /* end of record */
 571                                 state = HW_NONE;
 572                                 strv_clear(match_list);
 573                                 break;
 574                         }
 575
 576                         if (line[0] != ' ') {
 577                                 log_syntax(NULL, LOG_WARNING, filename, line_number, EINVAL,
 578                                            "Property or empty line expected, got \"%s\", ignoring record", line);
 579                                 r = -EINVAL;
 580                                 state = HW_NONE;
 581                                 strv_clear(match_list);
 582                                 break;
 583                         }
 584
 585                         err = insert_data(trie, match_list, line, filename, file_priority, line_number, compat);
 586                         if (err < 0)
 587                                 r = err;
 588                         break;
 589                 };
 590         }
 591
 592         if (state == HW_MATCH)
 593                 log_syntax(NULL, LOG_WARNING, filename, line_number, EINVAL,
 594                            "Property expected, ignoring record with no properties");
 595
 596         return r;
 597 }
 598
 599 int hwdb_update(const char *root, const char *hwdb_bin_dir, bool strict, bool compat) {
 600         _cleanup_free_ char *hwdb_bin = NULL;
 601         _cleanup_(trie_freep) struct trie *trie = NULL;
 602         _cleanup_strv_free_ char **files = NULL;
 603         char **f;
 604         uint16_t file_priority = 1;
 605         int r = 0, err;
 606
 607         /* The argument 'compat' controls the format version of database. If false, then hwdb.bin will be created with
 608          * additional information such that priority, line number, and filename of database source. If true, then hwdb.bin
 609          * will be created without the information. systemd-hwdb command should set the argument false, and 'udevadm hwdb'
 610          * command should set it true. */
 611
 612         trie = new0(struct trie, 1);
 613         if (!trie)
 614                 return -ENOMEM;
 615
 616         /* string store */
 617         trie->strings = strbuf_new();
 618         if (!trie->strings)
 619                 return -ENOMEM;
 620
 621         /* index */
 622         trie->root = new0(struct trie_node, 1);
 623         if (!trie->root)
 624                 return -ENOMEM;
 625
 626         trie->nodes_count++;
 627
 628         err = conf_files_list_strv(&files, ".hwdb", root, 0, conf_file_dirs);
 629         if (err < 0)
 630                 return log_error_errno(err, "Failed to enumerate hwdb files: %m");
 631
 632         STRV_FOREACH(f, files) {
 633                 log_debug("Reading file \"%s\"", *f);
 634                 err = import_file(trie, *f, file_priority++, compat);
 635                 if (err < 0 && strict)
 636                         r = err;
 637         }
 638
 639         strbuf_complete(trie->strings);
 640
 641         log_debug("=== trie in-memory ===");
 642         log_debug("nodes:            %8zu bytes (%8zu)",
 643                   trie->nodes_count * sizeof(struct trie_node), trie->nodes_count);
 644         log_debug("children arrays:  %8zu bytes (%8zu)",
 645                   trie->children_count * sizeof(struct trie_child_entry), trie->children_count);
 646         log_debug("values arrays:    %8zu bytes (%8zu)",
 647                   trie->values_count * sizeof(struct trie_value_entry), trie->values_count);
 648         log_debug("strings:          %8zu bytes",
 649                   trie->strings->len);
 650         log_debug("strings incoming: %8zu bytes (%8zu)",
 651                   trie->strings->in_len, trie->strings->in_count);
 652         log_debug("strings dedup'ed: %8zu bytes (%8zu)",
 653                   trie->strings->dedup_len, trie->strings->dedup_count);
 654
 655         hwdb_bin = path_join(root, hwdb_bin_dir ?: default_hwdb_bin_dir, "hwdb.bin");
 656         if (!hwdb_bin)
 657                 return -ENOMEM;
 658
 659         mkdir_parents_label(hwdb_bin, 0755);
 660         err = trie_store(trie, hwdb_bin, compat);
 661         if (err < 0)
 662                 return log_error_errno(err, "Failed to write database %s: %m", hwdb_bin);
 663
 664         err = label_fix(hwdb_bin, 0);
 665         if (err < 0)
 666                 return err;
 667
 668         return r;
 669 }
 670
 671 int hwdb_query(const char *modalias) {
 672         _cleanup_(sd_hwdb_unrefp) sd_hwdb *hwdb = NULL;
 673         const char *key, *value;
 674         int r;
 675
 676         assert(modalias);
 677
 678         r = sd_hwdb_new(&hwdb);
 679         if (r < 0)
 680                 return r;
 681
 682         SD_HWDB_FOREACH_PROPERTY(hwdb, modalias, key, value)
 683                 printf("%s=%s\n", key, value);
 684
 685         return 0;
 686 }