git.ozlabs.org Git - petitboot/blob - discover/paths.c

   1 #if defined(HAVE_CONFIG_H)
   2 #include "config.h"
   3 #endif
   4
   5 #include <assert.h>
   6 #include <string.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <sys/types.h>
  10 #include <sys/stat.h>
  11
  12 #include <talloc/talloc.h>
  13 #include <system/system.h>
  14 #include <process/process.h>
  15 #include <url/url.h>
  16 #include <log/log.h>
  17
  18 #include "paths.h"
  19
  20 #define DEVICE_MOUNT_BASE (LOCAL_STATE_DIR "/petitboot/mnt")
  21
  22 struct load_task {
  23         struct pb_url           *url;
  24         struct process          *process;
  25         struct load_url_result  *result;
  26         bool                    async;
  27         load_url_complete       async_cb;
  28         void                    *async_data;
  29 };
  30
  31 const char *mount_base(void)
  32 {
  33         return DEVICE_MOUNT_BASE;
  34 }
  35
  36 char *join_paths(void *alloc_ctx, const char *a, const char *b)
  37 {
  38         char *full_path;
  39
  40         full_path = talloc_array(alloc_ctx, char, strlen(a) + strlen(b) + 2);
  41
  42         strcpy(full_path, a);
  43         if (b[0] != '/' && a[strlen(a) - 1] != '/')
  44                 strcat(full_path, "/");
  45         strcat(full_path, b);
  46
  47         return full_path;
  48 }
  49
  50
  51 static char *local_name(void *ctx)
  52 {
  53         char *ret, tmp[] = "/tmp/pb-XXXXXX";
  54         mode_t oldmask;
  55         int fd;
  56
  57         oldmask = umask(0644);
  58         fd = mkstemp(tmp);
  59         umask(oldmask);
  60
  61         if (fd < 0)
  62                 return NULL;
  63
  64         close(fd);
  65
  66         ret = talloc_strdup(ctx, tmp);
  67
  68         return ret;
  69 }
  70
  71 static void load_url_result_cleanup_local(struct load_url_result *result)
  72 {
  73         if (result->cleanup_local)
  74                 unlink(result->local);
  75 }
  76
  77 static void load_url_process_exit(struct process *process)
  78 {
  79         struct load_task *task = process->data;
  80         struct load_url_result *result;
  81         load_url_complete cb;
  82         void *data;
  83
  84         pb_debug("The download client '%s' [pid %d, url %s] exited, rc %d\n",
  85                         process->path, process->pid, task->url->full,
  86                         process->exit_status);
  87
  88         result = task->result;
  89         data = task->async_data;
  90         cb = task->async_cb;
  91
  92         if (result->status == LOAD_CANCELLED) {
  93                 load_url_result_cleanup_local(result);
  94         } else if (process_exit_ok(process)) {
  95                 result->status = LOAD_OK;
  96         } else {
  97                 result->status = LOAD_ERROR;
  98                 load_url_result_cleanup_local(result);
  99         }
 100
 101         /* The load callback may well free the ctx, which was the
 102          * talloc parent of the task. Therefore, we want to do our cleanup
 103          * before invoking it
 104          */
 105         process_release(process);
 106         talloc_free(task);
 107         result->task = NULL;
 108
 109         cb(result, data);
 110 }
 111
 112 static void load_process_to_local_file(struct load_task *task,
 113                 const char **argv, int argv_local_idx)
 114 {
 115         int rc;
 116
 117         task->result->local = local_name(task->result);
 118         if (!task->result->local) {
 119                 task->result->status = LOAD_ERROR;
 120                 return;
 121         }
 122         task->result->cleanup_local = true;
 123
 124         if (argv_local_idx)
 125                 argv[argv_local_idx] = task->result->local;
 126
 127         task->process->argv = argv;
 128         task->process->path = argv[0];
 129
 130         if (task->async) {
 131                 rc = process_run_async(task->process);
 132                 if (rc) {
 133                         process_release(task->process);
 134                         task->process = NULL;
 135                 }
 136                 task->result->status = rc ? LOAD_ERROR : LOAD_ASYNC;
 137         } else {
 138                 rc = process_run_sync(task->process);
 139                 if (rc || !process_exit_ok(task->process))
 140                         task->result->status = LOAD_ERROR;
 141                 else
 142                         task->result->status = LOAD_OK;
 143                 process_release(task->process);
 144                 task->process = NULL;
 145         }
 146 }
 147
 148 /**
 149  * pb_load_nfs - Create a mountpoint, set the local file within that
 150  * mountpoint, and run the appropriate mount command
 151  */
 152
 153 static void load_nfs(struct load_task *task)
 154 {
 155         char *mountpoint, *opts;
 156         int rc;
 157         const char *argv[] = {
 158                         pb_system_apps.mount,
 159                         "-t", "nfs",
 160                         NULL,                   /* 3: opts */
 161                         task->url->host,
 162                         task->url->dir,
 163                         NULL,                   /* 6: mountpoint */
 164                         NULL,
 165         };
 166
 167         task->result->status = LOAD_ERROR;
 168         mountpoint = local_name(task->result);
 169         if (!mountpoint)
 170                 return;
 171         task->result->cleanup_local = true;
 172         argv[6] = mountpoint;
 173
 174         rc = pb_mkdir_recursive(mountpoint);
 175         if (rc)
 176                 return;
 177
 178         opts = talloc_strdup(NULL, "ro,nolock,nodiratime");
 179         argv[3] = opts;
 180
 181         if (task->url->port)
 182                 opts = talloc_asprintf_append(opts, ",port=%s",
 183                                                 task->url->port);
 184
 185         task->result->local = talloc_asprintf(task->result, "%s/%s",
 186                                                         mountpoint,
 187                                                         task->url->path);
 188
 189         task->process->path = pb_system_apps.mount;
 190         task->process->argv = argv;
 191
 192         if (task->async) {
 193                 rc = process_run_async(task->process);
 194                 if (rc) {
 195                         process_release(task->process);
 196                         task->process = NULL;
 197                 }
 198                 task->result->status = rc ? LOAD_ERROR : LOAD_ASYNC;
 199         } else {
 200                 rc = process_run_sync(task->process);
 201                 task->result->status = rc ? LOAD_ERROR : LOAD_OK;
 202                 process_release(task->process);
 203                 task->process = NULL;
 204         }
 205
 206         talloc_free(opts);
 207 }
 208
 209 static void load_sftp(struct load_task *task)
 210 {
 211         const char *argv[] = {
 212                         pb_system_apps.sftp,
 213                         NULL,           /* 1: host:path */
 214                         NULL,           /* 2: local file */
 215                         NULL,
 216         };
 217
 218         argv[1] = talloc_asprintf(task, "%s:%s",
 219                                 task->url->host, task->url->path);
 220         load_process_to_local_file(task, argv, 2);
 221 }
 222
 223 static enum tftp_type check_tftp_type(void *ctx)
 224 {
 225         const char *argv[] = { pb_system_apps.tftp, "-V", NULL };
 226         struct process *process;
 227         enum tftp_type type;
 228         int rc;
 229
 230         process = process_create(ctx);
 231         process->path = pb_system_apps.tftp;
 232         process->argv = argv;
 233         process->keep_stdout = true;
 234         process->add_stderr = true;
 235         rc = process_run_sync(process);
 236
 237         if (rc || !process->stdout_buf || process->stdout_len == 0) {
 238                 pb_log("Can't check TFTP client type!\n");
 239                 type = TFTP_TYPE_BROKEN;
 240
 241         } else if (memmem(process->stdout_buf, process->stdout_len,
 242                                 "tftp-hpa", strlen("tftp-hpa"))) {
 243                 pb_debug("Found TFTP client type: tftp-hpa\n");
 244                 type = TFTP_TYPE_HPA;
 245
 246         } else if (memmem(process->stdout_buf, process->stdout_len,
 247                                 "BusyBox", strlen("BusyBox"))) {
 248                 pb_debug("Found TFTP client type: BusyBox tftp\n");
 249                 type = TFTP_TYPE_BUSYBOX;
 250
 251         } else {
 252                 pb_log("Unknown TFTP client type!\n");
 253                 type = TFTP_TYPE_BROKEN;
 254         }
 255
 256         process_release(process);
 257         return type;
 258 }
 259
 260 static void load_tftp(struct load_task *task)
 261 {
 262         const char *port = "69";
 263         const char *argv[10] = {
 264                 pb_system_apps.tftp,
 265         };
 266
 267         if (task->url->port)
 268                 port = task->url->port;
 269
 270         if (tftp_type == TFTP_TYPE_UNKNOWN)
 271                 tftp_type = check_tftp_type(task);
 272
 273         if (tftp_type == TFTP_TYPE_BUSYBOX) {
 274                 argv[1] = "-g";
 275                 argv[2] = "-l";
 276                 argv[3] = NULL; /* 3: local file */
 277                 argv[4] = "-r";
 278                 argv[5] = task->url->path;
 279                 argv[6] = task->url->host;
 280                 argv[7] = port;
 281                 argv[8] = NULL;
 282
 283                 load_process_to_local_file(task, argv, 3);
 284
 285         } else if (tftp_type == TFTP_TYPE_HPA) {
 286                 argv[1] = "-m";
 287                 argv[2] = "binary";
 288                 argv[3] = task->url->host;
 289                 argv[4] = port;
 290                 argv[5] = "-c";
 291                 argv[6] = "get";
 292                 argv[7] = task->url->path;
 293                 argv[8] = NULL; /* 8: local file */
 294                 argv[9] = NULL;
 295                 load_process_to_local_file(task, argv, 8);
 296
 297         } else
 298                 task->result->status = LOAD_ERROR;
 299 }
 300
 301 enum wget_flags {
 302         wget_empty = 0,
 303         wget_no_check_certificate = 1,
 304 };
 305
 306 /**
 307  * pb_load_wget - Loads a remote file via wget and returns the local file path.
 308  *
 309  * Returns the local file path in a talloc'ed character string on success,
 310  * or NULL on error.
 311  */
 312
 313 static void load_wget(struct load_task *task, int flags)
 314 {
 315         const char *argv[] = {
 316                 pb_system_apps.wget,
 317                 "-O",
 318                 NULL, /* 2: local file */
 319                 NULL, /* 3 (optional): --quiet */
 320                 NULL, /* 4 (optional): --no-check-certificate */
 321                 NULL, /* 5: URL */
 322                 NULL,
 323         };
 324         int i;
 325
 326         i = 3;
 327 #if !defined(DEBUG)
 328         argv[i++] = "--quiet";
 329 #endif
 330         if (flags & wget_no_check_certificate)
 331                 argv[i++] = "--no-check-certificate";
 332
 333         argv[i] = task->url->full;
 334
 335         load_process_to_local_file(task, argv, 2);
 336 }
 337
 338 /* Although we don't need to load anything for a local path (we just return
 339  * the path from the file:// URL), the other load helpers will error-out on
 340  * non-existant files. So, do the same here with an access() check on the local
 341  * filename.
 342  */
 343 static void load_local(struct load_task *task)
 344 {
 345         int rc;
 346
 347         rc = access(task->url->path, F_OK);
 348         if (rc) {
 349                 task->result->status = LOAD_ERROR;
 350         } else {
 351                 task->result->local = talloc_strdup(task->result,
 352                                                     task->url->path);
 353                 task->result->status = LOAD_OK;
 354         }
 355 }
 356
 357 /**
 358  * load_url - Loads a (possibly) remote URL and returns the local file
 359  * path.
 360  * @ctx: The talloc context to associate with the returned string.
 361  * @url: The remote file URL.
 362  * @tempfile: An optional variable pointer to be set when a temporary local
 363  *  file is created.
 364  * @url_cb: An optional callback pointer if the caller wants to load url
 365  *  asynchronously.
 366  *
 367  * Returns the local file path in a talloc'ed character string on success,
 368  * or NULL on error.
 369  */
 370
 371 struct load_url_result *load_url_async(void *ctx, struct pb_url *url,
 372                 load_url_complete async_cb, void *async_data)
 373 {
 374         struct load_url_result *result;
 375         struct load_task *task;
 376
 377         if (!url)
 378                 return NULL;
 379
 380         task = talloc_zero(ctx, struct load_task);
 381         task->url = url;
 382         task->async = async_cb != NULL;
 383         task->result = talloc_zero(ctx, struct load_url_result);
 384         task->result->task = task;
 385         task->process = process_create(task);
 386         if (task->async) {
 387                 task->async_cb = async_cb;
 388                 task->async_data = async_data;
 389                 task->process->exit_cb = load_url_process_exit;
 390                 task->process->data = task;
 391         }
 392
 393         switch (url->scheme) {
 394         case pb_url_ftp:
 395         case pb_url_http:
 396                 load_wget(task, 0);
 397                 break;
 398         case pb_url_https:
 399                 load_wget(task, wget_no_check_certificate);
 400                 break;
 401         case pb_url_nfs:
 402                 load_nfs(task);
 403                 break;
 404         case pb_url_sftp:
 405                 load_sftp(task);
 406                 break;
 407         case pb_url_tftp:
 408                 load_tftp(task);
 409                 break;
 410         default:
 411                 load_local(task);
 412                 break;
 413         }
 414
 415         result = task->result;
 416         if (result->status == LOAD_ERROR) {
 417                 load_url_result_cleanup_local(task->result);
 418                 talloc_free(result);
 419                 talloc_free(task);
 420                 return NULL;
 421         }
 422
 423         if (!task->async)
 424                 talloc_free(task);
 425
 426         return result;
 427 }
 428
 429 struct load_url_result *load_url(void *ctx, struct pb_url *url)
 430 {
 431         return load_url_async(ctx, url, NULL, NULL);
 432 }
 433
 434 void load_url_async_cancel(struct load_url_result *res)
 435 {
 436         struct load_task *task = res->task;
 437
 438         /* the completion callback may have already been called; this clears
 439          * res->task */
 440         if (!task)
 441                 return;
 442
 443         if (res->status == LOAD_CANCELLED)
 444                 return;
 445
 446         assert(task->async);
 447         assert(task->process);
 448
 449         res->status = LOAD_CANCELLED;
 450         process_stop_async(task->process);
 451 }