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