src/journal/journal-file.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2011 Lennart Poettering
   8
   9   systemd is free software; you can redistribute it and/or modify it
  10   under the terms of the GNU Lesser General Public License as published by
  11   the Free Software Foundation; either version 2.1 of the License, or
  12   (at your option) any later version.
  13
  14   systemd is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  21 ***/
  22
  23 #include <inttypes.h>
  24
  25 #if HAVE_GCRYPT
  26 #include <gcrypt.h>
  27 #endif
  28
  29 #include "sd-id128.h"
  30
  31 #include "hashmap.h"
  32 #include "journal-def.h"
  33 #include "macro.h"
  34 #include "mmap-cache.h"
  35 #include "sd-event.h"
  36 #include "sparse-endian.h"
  37
  38 typedef struct JournalMetrics {
  39         /* For all these: -1 means "pick automatically", and 0 means "no limit enforced" */
  40         uint64_t max_size;     /* how large journal files grow at max */
  41         uint64_t min_size;     /* how large journal files grow at least */
  42         uint64_t max_use;      /* how much disk space to use in total at max, keep_free permitting */
  43         uint64_t min_use;      /* how much disk space to use in total at least, even if keep_free says not to */
  44         uint64_t keep_free;    /* how much to keep free on disk */
  45         uint64_t n_max_files;  /* how many files to keep around at max */
  46 } JournalMetrics;
  47
  48 typedef enum direction {
  49         DIRECTION_UP,
  50         DIRECTION_DOWN
  51 } direction_t;
  52
  53 typedef enum LocationType {
  54         /* The first and last entries, resp. */
  55         LOCATION_HEAD,
  56         LOCATION_TAIL,
  57
  58         /* We already read the entry we currently point to, and the
  59          * next one to read should probably not be this one again. */
  60         LOCATION_DISCRETE,
  61
  62         /* We should seek to the precise location specified, and
  63          * return it, as we haven't read it yet. */
  64         LOCATION_SEEK
  65 } LocationType;
  66
  67 typedef enum OfflineState {
  68         OFFLINE_JOINED,
  69         OFFLINE_SYNCING,
  70         OFFLINE_OFFLINING,
  71         OFFLINE_CANCEL,
  72         OFFLINE_AGAIN_FROM_SYNCING,
  73         OFFLINE_AGAIN_FROM_OFFLINING,
  74         OFFLINE_DONE
  75 } OfflineState;
  76
  77 typedef struct JournalFile {
  78         int fd;
  79         MMapFileDescriptor *cache_fd;
  80
  81         mode_t mode;
  82
  83         int flags;
  84         int prot;
  85         bool writable:1;
  86         bool compress_xz:1;
  87         bool compress_lz4:1;
  88         bool seal:1;
  89         bool defrag_on_close:1;
  90         bool close_fd:1;
  91         bool archive:1;
  92
  93         bool tail_entry_monotonic_valid:1;
  94
  95         direction_t last_direction;
  96         LocationType location_type;
  97         uint64_t last_n_entries;
  98
  99         char *path;
 100         struct stat last_stat;
 101         usec_t last_stat_usec;
 102
 103         Header *header;
 104         HashItem *data_hash_table;
 105         HashItem *field_hash_table;
 106
 107         uint64_t current_offset;
 108         uint64_t current_seqnum;
 109         uint64_t current_realtime;
 110         uint64_t current_monotonic;
 111         sd_id128_t current_boot_id;
 112         uint64_t current_xor_hash;
 113
 114         JournalMetrics metrics;
 115         MMapCache *mmap;
 116
 117         sd_event_source *post_change_timer;
 118         usec_t post_change_timer_period;
 119
 120         OrderedHashmap *chain_cache;
 121
 122         pthread_t offline_thread;
 123         volatile OfflineState offline_state;
 124
 125 #if HAVE_XZ || HAVE_LZ4
 126         void *compress_buffer;
 127         size_t compress_buffer_size;
 128 #endif
 129
 130 #if HAVE_GCRYPT
 131         gcry_md_hd_t hmac;
 132         bool hmac_running;
 133
 134         FSSHeader *fss_file;
 135         size_t fss_file_size;
 136
 137         uint64_t fss_start_usec;
 138         uint64_t fss_interval_usec;
 139
 140         void *fsprg_state;
 141         size_t fsprg_state_size;
 142
 143         void *fsprg_seed;
 144         size_t fsprg_seed_size;
 145 #endif
 146 } JournalFile;
 147
 148 int journal_file_open(
 149                 int fd,
 150                 const char *fname,
 151                 int flags,
 152                 mode_t mode,
 153                 bool compress,
 154                 bool seal,
 155                 JournalMetrics *metrics,
 156                 MMapCache *mmap_cache,
 157                 Set *deferred_closes,
 158                 JournalFile *template,
 159                 JournalFile **ret);
 160
 161 int journal_file_set_offline(JournalFile *f, bool wait);
 162 bool journal_file_is_offlining(JournalFile *f);
 163 JournalFile* journal_file_close(JournalFile *j);
 164 void journal_file_close_set(Set *s);
 165
 166 int journal_file_open_reliably(
 167                 const char *fname,
 168                 int flags,
 169                 mode_t mode,
 170                 bool compress,
 171                 bool seal,
 172                 JournalMetrics *metrics,
 173                 MMapCache *mmap_cache,
 174                 Set *deferred_closes,
 175                 JournalFile *template,
 176                 JournalFile **ret);
 177
 178 #define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
 179 #define VALID64(x) (((x) & 7ULL) == 0ULL)
 180
 181 /* Use six characters to cover the offsets common in smallish journal
 182  * files without adding too many zeros. */
 183 #define OFSfmt "%06"PRIx64
 184
 185 static inline bool VALID_REALTIME(uint64_t u) {
 186         /* This considers timestamps until the year 3112 valid. That should be plenty room... */
 187         return u > 0 && u < (1ULL << 55);
 188 }
 189
 190 static inline bool VALID_MONOTONIC(uint64_t u) {
 191         /* This considers timestamps until 1142 years of runtime valid. */
 192         return u < (1ULL << 55);
 193 }
 194
 195 static inline bool VALID_EPOCH(uint64_t u) {
 196         /* This allows changing the key for 1142 years, every usec. */
 197         return u < (1ULL << 55);
 198 }
 199
 200 #define JOURNAL_HEADER_CONTAINS(h, field) \
 201         (le64toh((h)->header_size) >= offsetof(Header, field) + sizeof((h)->field))
 202
 203 #define JOURNAL_HEADER_SEALED(h) \
 204         (!!(le32toh((h)->compatible_flags) & HEADER_COMPATIBLE_SEALED))
 205
 206 #define JOURNAL_HEADER_COMPRESSED_XZ(h) \
 207         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_XZ))
 208
 209 #define JOURNAL_HEADER_COMPRESSED_LZ4(h) \
 210         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_LZ4))
 211
 212 int journal_file_move_to_object(JournalFile *f, ObjectType type, uint64_t offset, Object **ret);
 213
 214 uint64_t journal_file_entry_n_items(Object *o) _pure_;
 215 uint64_t journal_file_entry_array_n_items(Object *o) _pure_;
 216 uint64_t journal_file_hash_table_n_items(Object *o) _pure_;
 217
 218 int journal_file_append_object(JournalFile *f, ObjectType type, uint64_t size, Object **ret, uint64_t *offset);
 219 int journal_file_append_entry(JournalFile *f, const dual_timestamp *ts, const struct iovec iovec[], unsigned n_iovec, uint64_t *seqno, Object **ret, uint64_t *offset);
 220
 221 int journal_file_find_data_object(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset);
 222 int journal_file_find_data_object_with_hash(JournalFile *f, const void *data, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 223
 224 int journal_file_find_field_object(JournalFile *f, const void *field, uint64_t size, Object **ret, uint64_t *offset);
 225 int journal_file_find_field_object_with_hash(JournalFile *f, const void *field, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 226
 227 void journal_file_reset_location(JournalFile *f);
 228 void journal_file_save_location(JournalFile *f, Object *o, uint64_t offset);
 229 int journal_file_compare_locations(JournalFile *af, JournalFile *bf);
 230 int journal_file_next_entry(JournalFile *f, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
 231
 232 int journal_file_next_entry_for_data(JournalFile *f, Object *o, uint64_t p, uint64_t data_offset, direction_t direction, Object **ret, uint64_t *offset);
 233
 234 int journal_file_move_to_entry_by_seqnum(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
 235 int journal_file_move_to_entry_by_realtime(JournalFile *f, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
 236 int journal_file_move_to_entry_by_monotonic(JournalFile *f, sd_id128_t boot_id, uint64_t monotonic, direction_t direction, Object **ret, uint64_t *offset);
 237
 238 int journal_file_move_to_entry_by_offset_for_data(JournalFile *f, uint64_t data_offset, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
 239 int journal_file_move_to_entry_by_seqnum_for_data(JournalFile *f, uint64_t data_offset, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
 240 int journal_file_move_to_entry_by_realtime_for_data(JournalFile *f, uint64_t data_offset, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
 241 int journal_file_move_to_entry_by_monotonic_for_data(JournalFile *f, uint64_t data_offset, sd_id128_t boot_id, uint64_t monotonic, direction_t direction, Object **ret, uint64_t *offset);
 242
 243 int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset);
 244
 245 void journal_file_dump(JournalFile *f);
 246 void journal_file_print_header(JournalFile *f);
 247
 248 int journal_file_rotate(JournalFile **f, bool compress, bool seal, Set *deferred_closes);
 249
 250 void journal_file_post_change(JournalFile *f);
 251 int journal_file_enable_post_change_timer(JournalFile *f, sd_event *e, usec_t t);
 252
 253 void journal_reset_metrics(JournalMetrics *m);
 254 void journal_default_metrics(JournalMetrics *m, int fd);
 255
 256 int journal_file_get_cutoff_realtime_usec(JournalFile *f, usec_t *from, usec_t *to);
 257 int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot, usec_t *from, usec_t *to);
 258
 259 bool journal_file_rotate_suggested(JournalFile *f, usec_t max_file_usec);
 260
 261 int journal_file_map_data_hash_table(JournalFile *f);
 262 int journal_file_map_field_hash_table(JournalFile *f);
 263
 264 static inline bool JOURNAL_FILE_COMPRESS(JournalFile *f) {
 265         assert(f);
 266         return f->compress_xz || f->compress_lz4;
 267 }