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

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