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