| 1 | #include <stdio.h> |
| 2 | #include <stdlib.h> |
| 3 | #include <string.h> |
| 4 | #include <unistd.h> |
| 5 | #include <stdbool.h> |
| 6 | |
| 7 | #define MAX_SEARCH 3 |
| 8 | #define MAX_PARAMETERS 128 |
| 9 | #define ERROR_BUFFER_SIZE 1024 |
| 10 | |
| 11 | struct command { |
| 12 | const char *name; |
| 13 | const char *params; |
| 14 | const char *search[MAX_SEARCH]; |
| 15 | } allowed_commands[] = { |
| 16 | { |
| 17 | .name = "ethtool-module-info", |
| 18 | .params = "-m {{devname}}", |
| 19 | .search = |
| 20 | { |
| 21 | [0] = "ethtool", |
| 22 | [1] = NULL, |
| 23 | }, |
| 24 | }, |
| 25 | { |
| 26 | .name = "chronyc-serverstats", |
| 27 | .params = "serverstats", |
| 28 | .search = |
| 29 | { |
| 30 | [0] = "chronyc", |
| 31 | [1] = NULL, |
| 32 | }, |
| 33 | }, |
| 34 | { |
| 35 | .name = "varnishadm-backend-list", |
| 36 | .params = "backend.list", |
| 37 | .search = |
| 38 | { |
| 39 | [0] = "varnishadm", |
| 40 | [1] = NULL, |
| 41 | }, |
| 42 | }, |
| 43 | { |
| 44 | .name = "varnishstat-stats", |
| 45 | .params = "-1 -t off -n {{instanceName}}", |
| 46 | .search = |
| 47 | { |
| 48 | [0] = "varnishstat", |
| 49 | [1] = NULL, |
| 50 | }, |
| 51 | }, |
| 52 | { |
| 53 | .name = "smbstatus-profile", |
| 54 | .params = "-P", |
| 55 | .search = |
| 56 | { |
| 57 | [0] = "smbstatus", |
| 58 | [1] = NULL, |
| 59 | }, |
| 60 | }, |
| 61 | { |
| 62 | .name = "exim-bpc", |
| 63 | .params = "-bpc", |
| 64 | .search = |
| 65 | { |
| 66 | [0] = "exim", |
| 67 | [1] = NULL, |
| 68 | }, |
| 69 | }, |
| 70 | { |
| 71 | .name = "nsd-control-stats", |
| 72 | .params = "stats_noreset", |
| 73 | .search = { |
| 74 | [0] = "nsd-control", |
| 75 | [1] = NULL, |
| 76 | }, |
| 77 | }, |
| 78 | { |
| 79 | .name = "chronyc-serverstats", |
| 80 | .params = "serverstats", |
| 81 | .search = { |
| 82 | [0] = "chronyc", |
| 83 | [1] = NULL, |
| 84 | }, |
| 85 | }, |
| 86 | { |
| 87 | .name = "dmsetup-status-cache", |
| 88 | .params = "status --target cache --noflush", |
| 89 | .search = { |
| 90 | [0] = "dmsetup", |
| 91 | [1] = NULL, |
| 92 | }, |
| 93 | }, |
| 94 | { |
| 95 | .name = "ssacli-controllers-info", |
| 96 | .params = "ctrl all show config detail", |
| 97 | .search = { |
| 98 | [0] = "ssacli", |
| 99 | [1] = NULL, |
| 100 | }, |
| 101 | }, |
| 102 | { |
| 103 | .name = "smartctl-json-scan", |
| 104 | .params = "--json --scan", |
| 105 | .search = { |
| 106 | [0] = "smartctl", |
| 107 | [1] = NULL, |
| 108 | }, |
| 109 | }, |
| 110 | { |
| 111 | .name = "smartctl-json-scan-open", |
| 112 | .params = "--json --scan-open", |
| 113 | .search = { |
| 114 | [0] = "smartctl", |
| 115 | [1] = NULL, |
| 116 | }, |
| 117 | }, |
| 118 | { |
| 119 | .name = "smartctl-json-device-info", |
| 120 | .params = "--json --all {{deviceName}} --device {{deviceType}} --nocheck {{powerMode}}", |
| 121 | .search = { |
| 122 | [0] = "smartctl", |
| 123 | [1] = NULL, |
| 124 | }, |
| 125 | }, |
| 126 | { |
| 127 | .name = "fail2ban-client-status", |
| 128 | .params = "status", |
| 129 | .search = { |
| 130 | [0] = "fail2ban-client", |
| 131 | [1] = NULL, |
| 132 | }, |
| 133 | }, |
| 134 | { |
| 135 | .name = "fail2ban-client-status-socket", |
| 136 | .params = "-s {{socket_path}} status", |
| 137 | .search = { |
| 138 | [0] = "fail2ban-client", |
| 139 | [1] = NULL, |
| 140 | }, |
| 141 | }, |
| 142 | { |
| 143 | .name = "fail2ban-client-status-jail", |
| 144 | .params = "status {{jail}}", |
| 145 | .search = { |
| 146 | [0] = "fail2ban-client", |
| 147 | [1] = NULL, |
| 148 | }, |
| 149 | }, |
| 150 | { |
| 151 | .name = "fail2ban-client-status-jail-socket", |
| 152 | .params = "-s {{socket_path}} status {{jail}}", |
| 153 | .search = { |
| 154 | [0] = "fail2ban-client", |
| 155 | [1] = NULL, |
| 156 | }, |
| 157 | }, |
| 158 | { |
| 159 | .name = "storcli-controllers-info", |
| 160 | .params = "/cALL show all J nolog", |
| 161 | .search = { |
| 162 | [0] = "storcli", |
| 163 | [1] = NULL, |
| 164 | }, |
| 165 | }, |
| 166 | { |
| 167 | .name = "storcli-drives-info", |
| 168 | .params = "/cALL/eALL/sALL show all J nolog", |
| 169 | .search = { |
| 170 | [0] = "storcli", |
| 171 | [1] = NULL, |
| 172 | }, |
| 173 | }, |
| 174 | { |
| 175 | .name = "lvs-report-json", |
| 176 | .params = "--reportformat json --units b --nosuffix -o {{options}}", |
| 177 | .search = { |
| 178 | [0] = "lvs", |
| 179 | [1] = NULL, |
| 180 | }, |
| 181 | }, |
| 182 | { |
| 183 | .name = "igt-list-gpus", |
| 184 | .params = "-L", |
| 185 | .search = { |
| 186 | [0] = "intel_gpu_top", |
| 187 | [1] = NULL, |
| 188 | }, |
| 189 | }, |
| 190 | { |
| 191 | .name = "igt-device-json", |
| 192 | .params = "-d {{device}} -J -s {{interval}}", |
| 193 | .search = { |
| 194 | [0] = "intel_gpu_top", |
| 195 | [1] = NULL, |
| 196 | }, |
| 197 | }, |
| 198 | { |
| 199 | .name = "igt-json", |
| 200 | .params = "-J -s {{interval}}", |
| 201 | .search = { |
| 202 | [0] = "intel_gpu_top", |
| 203 | [1] = NULL, |
| 204 | }, |
| 205 | }, |
| 206 | { |
| 207 | .name = "nvme-list", |
| 208 | .params = "list --output-format=json", |
| 209 | .search = { |
| 210 | [0] = "nvme", |
| 211 | [1] = NULL, |
| 212 | }, |
| 213 | }, |
| 214 | { |
| 215 | .name = "nvme-smart-log", |
| 216 | .params = "smart-log {{device}} --output-format=json", |
| 217 | .search = { |
| 218 | [0] = "nvme", |
| 219 | [1] = NULL, |
| 220 | }, |
| 221 | }, |
| 222 | { |
| 223 | .name = "megacli-disk-info", |
| 224 | .params = "-LDPDInfo -aAll -NoLog", |
| 225 | .search = { |
| 226 | [0] = "megacli", |
| 227 | [1] = "MegaCli", |
| 228 | [2] = "MegaCli64", |
| 229 | }, |
| 230 | }, |
| 231 | { |
| 232 | .name = "megacli-battery-info", |
| 233 | .params = "-AdpBbuCmd -aAll -NoLog", |
| 234 | .search = { |
| 235 | [0] = "megacli", |
| 236 | [1] = "MegaCli", |
| 237 | [2] = "MegaCli64", |
| 238 | }, |
| 239 | }, |
| 240 | { |
| 241 | .name = "arcconf-ld-info", |
| 242 | .params = "GETCONFIG 1 LD", |
| 243 | .search = { |
| 244 | [0] = "arcconf", |
| 245 | [1] = NULL, |
| 246 | }, |
| 247 | }, |
| 248 | { |
| 249 | .name = "arcconf-pd-info", |
| 250 | .params = "GETCONFIG 1 PD", |
| 251 | .search = { |
| 252 | [0] = "arcconf", |
| 253 | [1] = NULL, |
| 254 | }, |
| 255 | } |
| 256 | }; |
| 257 | |
| 258 | bool command_exists_in_dir(const char *dir, const char *cmd, char *dst, size_t dst_size) { |
| 259 | snprintf(dst, dst_size, "%s/%s", dir, cmd); |
| 260 | return access(dst, X_OK) == 0; |
| 261 | } |
| 262 | |
| 263 | bool command_exists_in_PATH(const char *cmd, char *dst, size_t dst_size) { |
| 264 | if(!dst || !dst_size) |
| 265 | return false; |
| 266 | |
| 267 | char *path = getenv("PATH"); |
| 268 | if(!path) |
| 269 | return false; |
| 270 | |
| 271 | char *path_copy = strdup(path); |
| 272 | if (!path_copy) |
| 273 | return false; |
| 274 | |
| 275 | char *dir; |
| 276 | bool found = false; |
| 277 | dir = strtok(path_copy, ":"); |
| 278 | while(dir && !found) { |
| 279 | found = command_exists_in_dir(dir, cmd, dst, dst_size); |
| 280 | dir = strtok(NULL, ":"); |
| 281 | } |
| 282 | |
| 283 | free(path_copy); |
| 284 | return found; |
| 285 | } |
| 286 | |
| 287 | struct command *find_command(const char *cmd) { |
| 288 | size_t size = sizeof(allowed_commands) / sizeof(allowed_commands[0]); |
| 289 | for(size_t i = 0; i < size ;i++) { |
| 290 | if(strcmp(cmd, allowed_commands[i].name) == 0) |
| 291 | return &allowed_commands[i]; |
| 292 | } |
| 293 | |
| 294 | return NULL; |
| 295 | } |
| 296 | |
| 297 | bool check_string(const char *str, size_t index, char *err, size_t err_size) { |
| 298 | const char *s = str; |
| 299 | while(*s) { |
| 300 | char c = *s++; |
| 301 | if(!((c >= 'A' && c <= 'Z') || |
| 302 | (c >= 'a' && c <= 'z') || |
| 303 | (c >= '0' && c <= '9') || |
| 304 | c == ' ' || c == '_' || c == '-' || c == '/' || |
| 305 | c == '.' || c == ',' || c == ':' || c == '=')) { |
| 306 | snprintf(err, err_size, "command line argument No %zu includes invalid character '%c'", index, c); |
| 307 | return false; |
| 308 | } |
| 309 | } |
| 310 | |
| 311 | return true; |
| 312 | } |
| 313 | |
| 314 | bool check_params(int argc, char **argv, char *err, size_t err_size) { |
| 315 | for(int i = 0 ; i < argc ;i++) |
| 316 | if(!check_string(argv[i], i, err, err_size)) |
| 317 | return false; |
| 318 | |
| 319 | return true; |
| 320 | } |
| 321 | |
| 322 | char *find_variable_in_argv(const char *variable, int argc, char **argv, char *err, size_t err_size) { |
| 323 | for (int i = 1; i < argc - 1; i++) { |
| 324 | if (strcmp(argv[i], variable) == 0) |
| 325 | return strdup(argv[i + 1]); |
| 326 | } |
| 327 | |
| 328 | snprintf(err, err_size, "variable '%s' is required, but was not provided in the command line parameters", variable); |
| 329 | |
| 330 | return NULL; |
| 331 | } |
| 332 | |
| 333 | bool search_and_replace_params(struct command *cmd, char **params, size_t max_params, const char *filename, int argc, char **argv, char *err, size_t err_size) { |
| 334 | if (!cmd || !params || !max_params) { |
| 335 | snprintf(err, err_size, "search_and_replace_params() internal error"); |
| 336 | return false; |
| 337 | } |
| 338 | |
| 339 | const char *delim = " "; |
| 340 | char *token; |
| 341 | char *temp_params = strdup(cmd->params); |
| 342 | if (!temp_params) { |
| 343 | snprintf(err, err_size, "search_and_replace_params() cannot allocate memory"); |
| 344 | return false; |
| 345 | } |
| 346 | |
| 347 | size_t param_count = 0; |
| 348 | params[param_count++] = strdup(filename); |
| 349 | |
| 350 | token = strtok(temp_params, delim); |
| 351 | while (token && param_count < max_params - 1) { |
| 352 | size_t len = strlen(token); |
| 353 | |
| 354 | char *value = NULL; |
| 355 | |
| 356 | if (strncmp(token, "{{", 2) == 0 && strncmp(token + len - 2, "}}", 2) == 0) { |
| 357 | token[0] = '-'; |
| 358 | token[1] = '-'; |
| 359 | token[len - 2] = '\0'; |
| 360 | |
| 361 | value = find_variable_in_argv(token, argc, argv, err, err_size); |
| 362 | } |
| 363 | else |
| 364 | value = strdup(token); |
| 365 | |
| 366 | if(!value) |
| 367 | goto cleanup; |
| 368 | |
| 369 | params[param_count++] = value; |
| 370 | token = strtok(NULL, delim); |
| 371 | } |
| 372 | |
| 373 | params[param_count] = NULL; // Null-terminate the params array |
| 374 | free(temp_params); |
| 375 | return true; |
| 376 | |
| 377 | cleanup: |
| 378 | if(!err[0]) |
| 379 | snprintf(err, err_size, "memory allocation failure"); |
| 380 | |
| 381 | free(temp_params); |
| 382 | for (size_t i = 0; i < param_count; ++i) { |
| 383 | free(params[i]); |
| 384 | params[i] = NULL; |
| 385 | } |
| 386 | return false; |
| 387 | } |
| 388 | |
| 389 | void show_help() { |
| 390 | fprintf(stdout, "\n"); |
| 391 | fprintf(stdout, "ndsudo\n"); |
| 392 | fprintf(stdout, "\n"); |
| 393 | fprintf(stdout, "Copyright 2018-2025 Netdata Inc.\n"); |
| 394 | fprintf(stdout, "\n"); |
| 395 | fprintf(stdout, "A helper to allow Netdata run privileged commands.\n"); |
| 396 | fprintf(stdout, "\n"); |
| 397 | fprintf(stdout, " --test\n"); |
| 398 | fprintf(stdout, " print the generated command that will be run, without running it.\n"); |
| 399 | fprintf(stdout, "\n"); |
| 400 | fprintf(stdout, " --help\n"); |
| 401 | fprintf(stdout, " print this message.\n"); |
| 402 | fprintf(stdout, "\n"); |
| 403 | |
| 404 | fprintf(stdout, "The following commands are supported:\n\n"); |
| 405 | |
| 406 | size_t size = sizeof(allowed_commands) / sizeof(allowed_commands[0]); |
| 407 | for(size_t i = 0; i < size ;i++) { |
| 408 | fprintf(stdout, "- Command : %s\n", allowed_commands[i].name); |
| 409 | fprintf(stdout, " Executables: "); |
| 410 | for(size_t j = 0; j < MAX_SEARCH && allowed_commands[i].search[j] ;j++) { |
| 411 | fprintf(stdout, "%s ", allowed_commands[i].search[j]); |
| 412 | } |
| 413 | fprintf(stdout, "\n"); |
| 414 | fprintf(stdout, " Parameters : %s\n\n", allowed_commands[i].params); |
| 415 | } |
| 416 | |
| 417 | fprintf(stdout, "The program searches for executables in the system path.\n"); |
| 418 | fprintf(stdout, "\n"); |
| 419 | fprintf(stdout, "Variables given as {{variable}} are expected on the command line as:\n"); |
| 420 | fprintf(stdout, " --variable VALUE\n"); |
| 421 | fprintf(stdout, "\n"); |
| 422 | fprintf(stdout, "VALUE can include space, A-Z, a-z, 0-9, _, -, /, and .\n"); |
| 423 | fprintf(stdout, "\n"); |
| 424 | } |
| 425 | |
| 426 | int main(int argc, char *argv[]) { |
| 427 | char error_buffer[ERROR_BUFFER_SIZE] = ""; |
| 428 | |
| 429 | if (argc < 2) { |
| 430 | fprintf(stderr, "at least 2 parameters are needed, but %d were given.\n", argc); |
| 431 | return 1; |
| 432 | } |
| 433 | |
| 434 | if(!check_params(argc, argv, error_buffer, sizeof(error_buffer))) { |
| 435 | fprintf(stderr, "invalid characters in parameters: %s\n", error_buffer); |
| 436 | return 2; |
| 437 | } |
| 438 | |
| 439 | bool test = false; |
| 440 | const char *cmd = argv[1]; |
| 441 | if(strcmp(cmd, "--help") == 0 || strcmp(cmd, "-h") == 0) { |
| 442 | show_help(); |
| 443 | exit(0); |
| 444 | } |
| 445 | else if(strcmp(cmd, "--test") == 0) { |
| 446 | cmd = argv[2]; |
| 447 | test = true; |
| 448 | } |
| 449 | |
| 450 | struct command *command = find_command(cmd); |
| 451 | if(!command) { |
| 452 | fprintf(stderr, "command not recognized: %s\n", cmd); |
| 453 | return 3; |
| 454 | } |
| 455 | |
| 456 | char new_path[] = "PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin"; |
| 457 | putenv(new_path); |
| 458 | |
| 459 | setuid(0); |
| 460 | setgid(0); |
| 461 | setegid(0); |
| 462 | |
| 463 | bool found = false; |
| 464 | char filename[FILENAME_MAX]; |
| 465 | |
| 466 | for(size_t i = 0; i < MAX_SEARCH && !found ;i++) { |
| 467 | if(command->search[i]) { |
| 468 | found = command_exists_in_PATH(command->search[i], filename, sizeof(filename)); |
| 469 | if(!found) { |
| 470 | size_t len = strlen(error_buffer); |
| 471 | snprintf(&error_buffer[len], sizeof(error_buffer) - len, "%s ", command->search[i]); |
| 472 | } |
| 473 | } |
| 474 | } |
| 475 | |
| 476 | if(!found) { |
| 477 | fprintf(stderr, "%s: not available in PATH.\n", error_buffer); |
| 478 | return 4; |
| 479 | } |
| 480 | else |
| 481 | error_buffer[0] = '\0'; |
| 482 | |
| 483 | char *params[MAX_PARAMETERS]; |
| 484 | if(!search_and_replace_params(command, params, MAX_PARAMETERS, filename, argc, argv, error_buffer, sizeof(error_buffer))) { |
| 485 | fprintf(stderr, "command line parameters are not satisfied: %s\n", error_buffer); |
| 486 | return 5; |
| 487 | } |
| 488 | |
| 489 | if(test) { |
| 490 | fprintf(stderr, "Command to run: \n"); |
| 491 | |
| 492 | for(size_t i = 0; i < MAX_PARAMETERS && params[i] ;i++) |
| 493 | fprintf(stderr, "'%s' ", params[i]); |
| 494 | |
| 495 | fprintf(stderr, "\n"); |
| 496 | |
| 497 | exit(0); |
| 498 | } |
| 499 | else { |
| 500 | char *clean_env[] = {NULL}; |
| 501 | execve(filename, params, clean_env); |
| 502 | perror("execve"); // execve only returns on error |
| 503 | return 6; |
| 504 | } |
| 505 | } |