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