src/import/import-tar.c

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