src/import/import-tar.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2015 Lennart Poettering
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <linux/fs.h>
  21
  22 #include "sd-daemon.h"
  23 #include "sd-event.h"
  24
  25 #include "alloc-util.h"
  26 #include "btrfs-util.h"
  27 #include "copy.h"
  28 #include "fd-util.h"
  29 #include "fileio.h"
  30 #include "fs-util.h"
  31 #include "hostname-util.h"
  32 #include "import-common.h"
  33 #include "import-compress.h"
  34 #include "import-tar.h"
  35 #include "io-util.h"
  36 #include "machine-pool.h"
  37 #include "mkdir.h"
  38 #include "path-util.h"
  39 #include "process-util.h"
  40 #include "qcow2-util.h"
  41 #include "ratelimit.h"
  42 #include "rm-rf.h"
  43 #include "string-util.h"
  44 #include "util.h"
  45
  46 struct TarImport {
  47         sd_event *event;
  48
  49         char *image_root;
  50
  51         TarImportFinished on_finished;
  52         void *userdata;
  53
  54         char *local;
  55         bool force_local;
  56         bool read_only;
  57         bool grow_machine_directory;
  58
  59         char *temp_path;
  60         char *final_path;
  61
  62         int input_fd;
  63         int tar_fd;
  64
  65         ImportCompress compress;
  66
  67         uint64_t written_since_last_grow;
  68
  69         sd_event_source *input_event_source;
  70
  71         uint8_t buffer[16*1024];
  72         size_t buffer_size;
  73
  74         uint64_t written_compressed;
  75         uint64_t written_uncompressed;
  76
  77         struct stat st;
  78
  79         pid_t tar_pid;
  80
  81         unsigned last_percent;
  82         RateLimit progress_rate_limit;
  83 };
  84
  85 TarImport* tar_import_unref(TarImport *i) {
  86         if (!i)
  87                 return NULL;
  88
  89         sd_event_source_unref(i->input_event_source);
  90
  91         if (i->tar_pid > 1) {
  92                 (void) kill_and_sigcont(i->tar_pid, SIGKILL);
  93                 (void) wait_for_terminate(i->tar_pid, NULL);
  94         }
  95
  96         if (i->temp_path) {
  97                 (void) rm_rf(i->temp_path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
  98                 free(i->temp_path);
  99         }
 100
 101         import_compress_free(&i->compress);
 102
 103         sd_event_unref(i->event);
 104
 105         safe_close(i->tar_fd);
 106
 107         free(i->final_path);
 108         free(i->image_root);
 109         free(i->local);
 110         return mfree(i);
 111 }
 112
 113 int tar_import_new(
 114                 TarImport **ret,
 115                 sd_event *event,
 116                 const char *image_root,
 117                 TarImportFinished on_finished,
 118                 void *userdata) {
 119
 120         _cleanup_(tar_import_unrefp) TarImport *i = NULL;
 121         int r;
 122
 123         assert(ret);
 124
 125         i = new0(TarImport, 1);
 126         if (!i)
 127                 return -ENOMEM;
 128
 129         i->input_fd = i->tar_fd = -1;
 130         i->on_finished = on_finished;
 131         i->userdata = userdata;
 132
 133         RATELIMIT_INIT(i->progress_rate_limit, 100 * USEC_PER_MSEC, 1);
 134         i->last_percent = (unsigned) -1;
 135
 136         i->image_root = strdup(image_root ?: "/var/lib/machines");
 137         if (!i->image_root)
 138                 return -ENOMEM;
 139
 140         i->grow_machine_directory = path_startswith(i->image_root, "/var/lib/machines");
 141
 142         if (event)
 143                 i->event = sd_event_ref(event);
 144         else {
 145                 r = sd_event_default(&i->event);
 146                 if (r < 0)
 147                         return r;
 148         }
 149
 150         *ret = i;
 151         i = NULL;
 152
 153         return 0;
 154 }
 155
 156 static void tar_import_report_progress(TarImport *i) {
 157         unsigned percent;
 158         assert(i);
 159
 160         /* We have no size information, unless the source is a regular file */
 161         if (!S_ISREG(i->st.st_mode))
 162                 return;
 163
 164         if (i->written_compressed >= (uint64_t) i->st.st_size)
 165                 percent = 100;
 166         else
 167                 percent = (unsigned) ((i->written_compressed * UINT64_C(100)) / (uint64_t) i->st.st_size);
 168
 169         if (percent == i->last_percent)
 170                 return;
 171
 172         if (!ratelimit_test(&i->progress_rate_limit))
 173                 return;
 174
 175         sd_notifyf(false, "X_IMPORT_PROGRESS=%u", percent);
 176         log_info("Imported %u%%.", percent);
 177
 178         i->last_percent = percent;
 179 }
 180
 181 static int tar_import_finish(TarImport *i) {
 182         int r;
 183
 184         assert(i);
 185         assert(i->tar_fd >= 0);
 186         assert(i->temp_path);
 187         assert(i->final_path);
 188
 189         i->tar_fd = safe_close(i->tar_fd);
 190
 191         if (i->tar_pid > 0) {
 192                 r = wait_for_terminate_and_warn("tar", i->tar_pid, true);
 193                 i->tar_pid = 0;
 194                 if (r < 0)
 195                         return r;
 196         }
 197
 198         if (i->read_only) {
 199                 r = import_make_read_only(i->temp_path);
 200                 if (r < 0)
 201                         return r;
 202         }
 203
 204         if (i->force_local)
 205                 (void) rm_rf(i->final_path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
 206
 207         r = rename_noreplace(AT_FDCWD, i->temp_path, AT_FDCWD, i->final_path);
 208         if (r < 0)
 209                 return log_error_errno(r, "Failed to move image into place: %m");
 210
 211         i->temp_path = mfree(i->temp_path);
 212
 213         return 0;
 214 }
 215
 216 static int tar_import_fork_tar(TarImport *i) {
 217         int r;
 218
 219         assert(i);
 220
 221         assert(!i->final_path);
 222         assert(!i->temp_path);
 223         assert(i->tar_fd < 0);
 224
 225         i->final_path = strjoin(i->image_root, "/", i->local, NULL);
 226         if (!i->final_path)
 227                 return log_oom();
 228
 229         r = tempfn_random(i->final_path, NULL, &i->temp_path);
 230         if (r < 0)
 231                 return log_oom();
 232
 233         (void) mkdir_parents_label(i->temp_path, 0700);
 234
 235         r = btrfs_subvol_make(i->temp_path);
 236         if (r == -ENOTTY) {
 237                 if (mkdir(i->temp_path, 0755) < 0)
 238                         return log_error_errno(errno, "Failed to create directory %s: %m", i->temp_path);
 239         } else if (r < 0)
 240                 return log_error_errno(r, "Failed to create subvolume %s: %m", i->temp_path);
 241         else
 242                 (void) import_assign_pool_quota_and_warn(i->temp_path);
 243
 244         i->tar_fd = import_fork_tar_x(i->temp_path, &i->tar_pid);
 245         if (i->tar_fd < 0)
 246                 return i->tar_fd;
 247
 248         return 0;
 249 }
 250
 251 static int tar_import_write(const void *p, size_t sz, void *userdata) {
 252         TarImport *i = userdata;
 253         int r;
 254
 255         if (i->grow_machine_directory && i->written_since_last_grow >= GROW_INTERVAL_BYTES) {
 256                 i->written_since_last_grow = 0;
 257                 grow_machine_directory();
 258         }
 259
 260         r = loop_write(i->tar_fd, p, sz, false);
 261         if (r < 0)
 262                 return r;
 263
 264         i->written_uncompressed += sz;
 265         i->written_since_last_grow += sz;
 266
 267         return 0;
 268 }
 269
 270 static int tar_import_process(TarImport *i) {
 271         ssize_t l;
 272         int r;
 273
 274         assert(i);
 275         assert(i->buffer_size < sizeof(i->buffer));
 276
 277         l = read(i->input_fd, i->buffer + i->buffer_size, sizeof(i->buffer) - i->buffer_size);
 278         if (l < 0) {
 279                 if (errno == EAGAIN)
 280                         return 0;
 281
 282                 r = log_error_errno(errno, "Failed to read input file: %m");
 283                 goto finish;
 284         }
 285         if (l == 0) {
 286                 if (i->compress.type == IMPORT_COMPRESS_UNKNOWN) {
 287                         log_error("Premature end of file: %m");
 288                         r = -EIO;
 289                         goto finish;
 290                 }
 291
 292                 r = tar_import_finish(i);
 293                 goto finish;
 294         }
 295
 296         i->buffer_size += l;
 297
 298         if (i->compress.type == IMPORT_COMPRESS_UNKNOWN) {
 299                 r = import_uncompress_detect(&i->compress, i->buffer, i->buffer_size);
 300                 if (r < 0) {
 301                         log_error("Failed to detect file compression: %m");
 302                         goto finish;
 303                 }
 304                 if (r == 0) /* Need more data */
 305                         return 0;
 306
 307                 r = tar_import_fork_tar(i);
 308                 if (r < 0)
 309                         goto finish;
 310         }
 311
 312         r = import_uncompress(&i->compress, i->buffer, i->buffer_size, tar_import_write, i);
 313         if (r < 0) {
 314                 log_error_errno(r, "Failed to decode and write: %m");
 315                 goto finish;
 316         }
 317
 318         i->written_compressed += i->buffer_size;
 319         i->buffer_size = 0;
 320
 321         tar_import_report_progress(i);
 322
 323         return 0;
 324
 325 finish:
 326         if (i->on_finished)
 327                 i->on_finished(i, r, i->userdata);
 328         else
 329                 sd_event_exit(i->event, r);
 330
 331         return 0;
 332 }
 333
 334 static int tar_import_on_input(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
 335         TarImport *i = userdata;
 336
 337         return tar_import_process(i);
 338 }
 339
 340 static int tar_import_on_defer(sd_event_source *s, void *userdata) {
 341         TarImport *i = userdata;
 342
 343         return tar_import_process(i);
 344 }
 345
 346 int tar_import_start(TarImport *i, int fd, const char *local, bool force_local, bool read_only) {
 347         int r;
 348
 349         assert(i);
 350         assert(fd >= 0);
 351         assert(local);
 352
 353         if (!machine_name_is_valid(local))
 354                 return -EINVAL;
 355
 356         if (i->input_fd >= 0)
 357                 return -EBUSY;
 358
 359         r = fd_nonblock(fd, true);
 360         if (r < 0)
 361                 return r;
 362
 363         r = free_and_strdup(&i->local, local);
 364         if (r < 0)
 365                 return r;
 366         i->force_local = force_local;
 367         i->read_only = read_only;
 368
 369         if (fstat(fd, &i->st) < 0)
 370                 return -errno;
 371
 372         r = sd_event_add_io(i->event, &i->input_event_source, fd, EPOLLIN, tar_import_on_input, i);
 373         if (r == -EPERM) {
 374                 /* This fd does not support epoll, for example because it is a regular file. Busy read in that case */
 375                 r = sd_event_add_defer(i->event, &i->input_event_source, tar_import_on_defer, i);
 376                 if (r < 0)
 377                         return r;
 378
 379                 r = sd_event_source_set_enabled(i->input_event_source, SD_EVENT_ON);
 380         }
 381         if (r < 0)
 382                 return r;
 383
 384         i->input_fd = fd;
 385         return r;
 386 }