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 "macro.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         bool defrag_on_close:1;
  77
  78         bool tail_entry_monotonic_valid:1;
  79
  80         direction_t last_direction;
  81         LocationType location_type;
  82         uint64_t last_n_entries;
  83
  84         char *path;
  85         struct stat last_stat;
  86         usec_t last_stat_usec;
  87
  88         Header *header;
  89         HashItem *data_hash_table;
  90         HashItem *field_hash_table;
  91
  92         uint64_t current_offset;
  93         uint64_t current_seqnum;
  94         uint64_t current_realtime;
  95         uint64_t current_monotonic;
  96         sd_id128_t current_boot_id;
  97         uint64_t current_xor_hash;
  98
  99         JournalMetrics metrics;
 100         MMapCache *mmap;
 101
 102         OrderedHashmap *chain_cache;
 103
 104 #if defined(HAVE_XZ) || defined(HAVE_LZ4)
 105         void *compress_buffer;
 106         size_t compress_buffer_size;
 107 #endif
 108
 109 #ifdef HAVE_GCRYPT
 110         gcry_md_hd_t hmac;
 111         bool hmac_running;
 112
 113         FSSHeader *fss_file;
 114         size_t fss_file_size;
 115
 116         uint64_t fss_start_usec;
 117         uint64_t fss_interval_usec;
 118
 119         void *fsprg_state;
 120         size_t fsprg_state_size;
 121
 122         void *fsprg_seed;
 123         size_t fsprg_seed_size;
 124 #endif
 125 } JournalFile;
 126
 127 int journal_file_open(
 128                 const char *fname,
 129                 int flags,
 130                 mode_t mode,
 131                 bool compress,
 132                 bool seal,
 133                 JournalMetrics *metrics,
 134                 MMapCache *mmap_cache,
 135                 JournalFile *template,
 136                 JournalFile **ret);
 137
 138 int journal_file_set_offline(JournalFile *f);
 139 void journal_file_close(JournalFile *j);
 140
 141 int journal_file_open_reliably(
 142                 const char *fname,
 143                 int flags,
 144                 mode_t mode,
 145                 bool compress,
 146                 bool seal,
 147                 JournalMetrics *metrics,
 148                 MMapCache *mmap_cache,
 149                 JournalFile *template,
 150                 JournalFile **ret);
 151
 152 #define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
 153 #define VALID64(x) (((x) & 7ULL) == 0ULL)
 154
 155 /* Use six characters to cover the offsets common in smallish journal
 156  * files without adding too many zeros. */
 157 #define OFSfmt "%06"PRIx64
 158
 159 static inline bool VALID_REALTIME(uint64_t u) {
 160         /* This considers timestamps until the year 3112 valid. That should be plenty room... */
 161         return u > 0 && u < (1ULL << 55);
 162 }
 163
 164 static inline bool VALID_MONOTONIC(uint64_t u) {
 165         /* This considers timestamps until 1142 years of runtime valid. */
 166         return u < (1ULL << 55);
 167 }
 168
 169 static inline bool VALID_EPOCH(uint64_t u) {
 170         /* This allows changing the key for 1142 years, every usec. */
 171         return u < (1ULL << 55);
 172 }
 173
 174 #define JOURNAL_HEADER_CONTAINS(h, field) \
 175         (le64toh((h)->header_size) >= offsetof(Header, field) + sizeof((h)->field))
 176
 177 #define JOURNAL_HEADER_SEALED(h) \
 178         (!!(le32toh((h)->compatible_flags) & HEADER_COMPATIBLE_SEALED))
 179
 180 #define JOURNAL_HEADER_COMPRESSED_XZ(h) \
 181         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_XZ))
 182
 183 #define JOURNAL_HEADER_COMPRESSED_LZ4(h) \
 184         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_LZ4))
 185
 186 int journal_file_move_to_object(JournalFile *f, ObjectType type, uint64_t offset, Object **ret);
 187
 188 uint64_t journal_file_entry_n_items(Object *o) _pure_;
 189 uint64_t journal_file_entry_array_n_items(Object *o) _pure_;
 190 uint64_t journal_file_hash_table_n_items(Object *o) _pure_;
 191
 192 int journal_file_append_object(JournalFile *f, ObjectType type, uint64_t size, Object **ret, uint64_t *offset);
 193 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);
 194
 195 int journal_file_find_data_object(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset);
 196 int journal_file_find_data_object_with_hash(JournalFile *f, const void *data, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 197
 198 int journal_file_find_field_object(JournalFile *f, const void *field, uint64_t size, Object **ret, uint64_t *offset);
 199 int journal_file_find_field_object_with_hash(JournalFile *f, const void *field, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 200
 201 void journal_file_reset_location(JournalFile *f);
 202 void journal_file_save_location(JournalFile *f, Object *o, uint64_t offset);
 203 int journal_file_compare_locations(JournalFile *af, JournalFile *bf);
 204 int journal_file_next_entry(JournalFile *f, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
 205
 206 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);
 207
 208 int journal_file_move_to_entry_by_seqnum(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
 209 int journal_file_move_to_entry_by_realtime(JournalFile *f, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
 210 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);
 211
 212 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);
 213 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);
 214 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);
 215 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);
 216
 217 int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset);
 218
 219 void journal_file_dump(JournalFile *f);
 220 void journal_file_print_header(JournalFile *f);
 221
 222 int journal_file_rotate(JournalFile **f, bool compress, bool seal);
 223
 224 void journal_file_post_change(JournalFile *f);
 225
 226 void journal_default_metrics(JournalMetrics *m, int fd);
 227
 228 int journal_file_get_cutoff_realtime_usec(JournalFile *f, usec_t *from, usec_t *to);
 229 int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot, usec_t *from, usec_t *to);
 230
 231 bool journal_file_rotate_suggested(JournalFile *f, usec_t max_file_usec);