src/journal/journal-file.h

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 #pragma once
   4
   5 /***
   6   This file is part of systemd.
   7
   8   Copyright 2011 Lennart Poettering
   9
  10   systemd is free software; you can redistribute it and/or modify it
  11   under the terms of the GNU Lesser General Public License as published by
  12   the Free Software Foundation; either version 2.1 of the License, or
  13   (at your option) any later version.
  14
  15   systemd is distributed in the hope that it will be useful, but
  16   WITHOUT ANY WARRANTY; without even the implied warranty of
  17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18   Lesser General Public License for more details.
  19
  20   You should have received a copy of the GNU Lesser General Public License
  21   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  22 ***/
  23
  24 #include <inttypes.h>
  25
  26 #ifdef HAVE_GCRYPT
  27 #include <gcrypt.h>
  28 #endif
  29
  30 #include "sd-id128.h"
  31
  32 #include "sparse-endian.h"
  33 #include "journal-def.h"
  34 #include "util.h"
  35 #include "mmap-cache.h"
  36 #include "hashmap.h"
  37
  38 typedef struct JournalMetrics {
  39         uint64_t max_use;
  40         uint64_t use;
  41         uint64_t max_size;
  42         uint64_t min_size;
  43         uint64_t keep_free;
  44 } JournalMetrics;
  45
  46 typedef enum direction {
  47         DIRECTION_UP,
  48         DIRECTION_DOWN
  49 } direction_t;
  50
  51 typedef enum LocationType {
  52         /* The first and last entries, resp. */
  53         LOCATION_HEAD,
  54         LOCATION_TAIL,
  55
  56         /* We already read the entry we currently point to, and the
  57          * next one to read should probably not be this one again. */
  58         LOCATION_DISCRETE,
  59
  60         /* We should seek to the precise location specified, and
  61          * return it, as we haven't read it yet. */
  62         LOCATION_SEEK
  63 } LocationType;
  64
  65 typedef struct JournalFile {
  66         int fd;
  67
  68         mode_t mode;
  69
  70         int flags;
  71         int prot;
  72         bool writable:1;
  73         bool compress_xz:1;
  74         bool compress_lz4:1;
  75         bool seal:1;
  76
  77         bool tail_entry_monotonic_valid:1;
  78
  79         direction_t last_direction;
  80         LocationType location_type;
  81         uint64_t last_n_entries;
  82
  83         char *path;
  84         struct stat last_stat;
  85         usec_t last_stat_usec;
  86
  87         Header *header;
  88         HashItem *data_hash_table;
  89         HashItem *field_hash_table;
  90
  91         uint64_t current_offset;
  92         uint64_t current_seqnum;
  93         uint64_t current_realtime;
  94         uint64_t current_monotonic;
  95         sd_id128_t current_boot_id;
  96         uint64_t current_xor_hash;
  97
  98         JournalMetrics metrics;
  99         MMapCache *mmap;
 100
 101         OrderedHashmap *chain_cache;
 102
 103 #if defined(HAVE_XZ) || defined(HAVE_LZ4)
 104         void *compress_buffer;
 105         size_t compress_buffer_size;
 106 #endif
 107
 108 #ifdef HAVE_GCRYPT
 109         gcry_md_hd_t hmac;
 110         bool hmac_running;
 111
 112         FSSHeader *fss_file;
 113         size_t fss_file_size;
 114
 115         uint64_t fss_start_usec;
 116         uint64_t fss_interval_usec;
 117
 118         void *fsprg_state;
 119         size_t fsprg_state_size;
 120
 121         void *fsprg_seed;
 122         size_t fsprg_seed_size;
 123 #endif
 124 } JournalFile;
 125
 126 int journal_file_open(
 127                 const char *fname,
 128                 int flags,
 129                 mode_t mode,
 130                 bool compress,
 131                 bool seal,
 132                 JournalMetrics *metrics,
 133                 MMapCache *mmap_cache,
 134                 JournalFile *template,
 135                 JournalFile **ret);
 136
 137 int journal_file_set_offline(JournalFile *f);
 138 void journal_file_close(JournalFile *j);
 139
 140 int journal_file_open_reliably(
 141                 const char *fname,
 142                 int flags,
 143                 mode_t mode,
 144                 bool compress,
 145                 bool seal,
 146                 JournalMetrics *metrics,
 147                 MMapCache *mmap_cache,
 148                 JournalFile *template,
 149                 JournalFile **ret);
 150
 151 #define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
 152 #define VALID64(x) (((x) & 7ULL) == 0ULL)
 153
 154 /* Use six characters to cover the offsets common in smallish journal
 155  * files without adding too many zeros. */
 156 #define OFSfmt "%06"PRIx64
 157
 158 static inline bool VALID_REALTIME(uint64_t u) {
 159         /* This considers timestamps until the year 3112 valid. That should be plenty room... */
 160         return u > 0 && u < (1ULL << 55);
 161 }
 162
 163 static inline bool VALID_MONOTONIC(uint64_t u) {
 164         /* This considers timestamps until 1142 years of runtime valid. */
 165         return u < (1ULL << 55);
 166 }
 167
 168 static inline bool VALID_EPOCH(uint64_t u) {
 169         /* This allows changing the key for 1142 years, every usec. */
 170         return u < (1ULL << 55);
 171 }
 172
 173 #define JOURNAL_HEADER_CONTAINS(h, field) \
 174         (le64toh((h)->header_size) >= offsetof(Header, field) + sizeof((h)->field))
 175
 176 #define JOURNAL_HEADER_SEALED(h) \
 177         (!!(le32toh((h)->compatible_flags) & HEADER_COMPATIBLE_SEALED))
 178
 179 #define JOURNAL_HEADER_COMPRESSED_XZ(h) \
 180         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_XZ))
 181
 182 #define JOURNAL_HEADER_COMPRESSED_LZ4(h) \
 183         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_LZ4))
 184
 185 int journal_file_move_to_object(JournalFile *f, ObjectType type, uint64_t offset, Object **ret);
 186
 187 uint64_t journal_file_entry_n_items(Object *o) _pure_;
 188 uint64_t journal_file_entry_array_n_items(Object *o) _pure_;
 189 uint64_t journal_file_hash_table_n_items(Object *o) _pure_;
 190
 191 int journal_file_append_object(JournalFile *f, ObjectType type, uint64_t size, Object **ret, uint64_t *offset);
 192 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);
 193
 194 int journal_file_find_data_object(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset);
 195 int journal_file_find_data_object_with_hash(JournalFile *f, const void *data, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 196
 197 int journal_file_find_field_object(JournalFile *f, const void *field, uint64_t size, Object **ret, uint64_t *offset);
 198 int journal_file_find_field_object_with_hash(JournalFile *f, const void *field, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 199
 200 void journal_file_reset_location(JournalFile *f);
 201 void journal_file_save_location(JournalFile *f, direction_t direction, Object *o, uint64_t offset);
 202 int journal_file_compare_locations(JournalFile *af, JournalFile *bf);
 203 int journal_file_next_entry(JournalFile *f, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
 204
 205 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);
 206
 207 int journal_file_move_to_entry_by_seqnum(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
 208 int journal_file_move_to_entry_by_realtime(JournalFile *f, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
 209 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);
 210
 211 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);
 212 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);
 213 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);
 214 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);
 215
 216 int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset);
 217
 218 void journal_file_dump(JournalFile *f);
 219 void journal_file_print_header(JournalFile *f);
 220
 221 int journal_file_rotate(JournalFile **f, bool compress, bool seal);
 222
 223 void journal_file_post_change(JournalFile *f);
 224
 225 void journal_default_metrics(JournalMetrics *m, int fd);
 226
 227 int journal_file_get_cutoff_realtime_usec(JournalFile *f, usec_t *from, usec_t *to);
 228 int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot, usec_t *from, usec_t *to);
 229
 230 bool journal_file_rotate_suggested(JournalFile *f, usec_t max_file_usec);