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 struct JournalFile {
  52         int fd;
  53
  54         mode_t mode;
  55
  56         int flags;
  57         int prot;
  58         bool writable:1;
  59         bool compress_xz:1;
  60         bool compress_lz4:1;
  61         bool seal:1;
  62
  63         bool tail_entry_monotonic_valid:1;
  64
  65         direction_t last_direction;
  66
  67         char *path;
  68         struct stat last_stat;
  69
  70         Header *header;
  71         HashItem *data_hash_table;
  72         HashItem *field_hash_table;
  73
  74         uint64_t current_offset;
  75
  76         JournalMetrics metrics;
  77         MMapCache *mmap;
  78
  79         Hashmap *chain_cache;
  80
  81 #if defined(HAVE_XZ) || defined(HAVE_LZ4)
  82         void *compress_buffer;
  83         size_t compress_buffer_size;
  84 #endif
  85
  86 #ifdef HAVE_GCRYPT
  87         gcry_md_hd_t hmac;
  88         bool hmac_running;
  89
  90         FSSHeader *fss_file;
  91         size_t fss_file_size;
  92
  93         uint64_t fss_start_usec;
  94         uint64_t fss_interval_usec;
  95
  96         void *fsprg_state;
  97         size_t fsprg_state_size;
  98
  99         void *fsprg_seed;
 100         size_t fsprg_seed_size;
 101 #endif
 102 } JournalFile;
 103
 104 int journal_file_open(
 105                 const char *fname,
 106                 int flags,
 107                 mode_t mode,
 108                 bool compress,
 109                 bool seal,
 110                 JournalMetrics *metrics,
 111                 MMapCache *mmap_cache,
 112                 JournalFile *template,
 113                 JournalFile **ret);
 114
 115 int journal_file_set_offline(JournalFile *f);
 116 void journal_file_close(JournalFile *j);
 117
 118 int journal_file_open_reliably(
 119                 const char *fname,
 120                 int flags,
 121                 mode_t mode,
 122                 bool compress,
 123                 bool seal,
 124                 JournalMetrics *metrics,
 125                 MMapCache *mmap_cache,
 126                 JournalFile *template,
 127                 JournalFile **ret);
 128
 129 #define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
 130 #define VALID64(x) (((x) & 7ULL) == 0ULL)
 131
 132 /* Use six characters to cover the offsets common in smallish journal
 133  * files without adding too many zeros. */
 134 #define OFSfmt "%06"PRIx64
 135
 136 static inline bool VALID_REALTIME(uint64_t u) {
 137         /* This considers timestamps until the year 3112 valid. That should be plenty room... */
 138         return u > 0 && u < (1ULL << 55);
 139 }
 140
 141 static inline bool VALID_MONOTONIC(uint64_t u) {
 142         /* This considers timestamps until 1142 years of runtime valid. */
 143         return u < (1ULL << 55);
 144 }
 145
 146 static inline bool VALID_EPOCH(uint64_t u) {
 147         /* This allows changing the key for 1142 years, every usec. */
 148         return u < (1ULL << 55);
 149 }
 150
 151 #define JOURNAL_HEADER_CONTAINS(h, field) \
 152         (le64toh((h)->header_size) >= offsetof(Header, field) + sizeof((h)->field))
 153
 154 #define JOURNAL_HEADER_SEALED(h) \
 155         (!!(le32toh((h)->compatible_flags) & HEADER_COMPATIBLE_SEALED))
 156
 157 #define JOURNAL_HEADER_COMPRESSED_XZ(h) \
 158         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_XZ))
 159
 160 #define JOURNAL_HEADER_COMPRESSED_LZ4(h) \
 161         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_LZ4))
 162
 163 int journal_file_move_to_object(JournalFile *f, int type, uint64_t offset, Object **ret);
 164
 165 uint64_t journal_file_entry_n_items(Object *o) _pure_;
 166 uint64_t journal_file_entry_array_n_items(Object *o) _pure_;
 167 uint64_t journal_file_hash_table_n_items(Object *o) _pure_;
 168
 169 int journal_file_append_object(JournalFile *f, int type, uint64_t size, Object **ret, uint64_t *offset);
 170 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);
 171
 172 int journal_file_find_data_object(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset);
 173 int journal_file_find_data_object_with_hash(JournalFile *f, const void *data, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 174
 175 int journal_file_find_field_object(JournalFile *f, const void *field, uint64_t size, Object **ret, uint64_t *offset);
 176 int journal_file_find_field_object_with_hash(JournalFile *f, const void *field, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 177
 178 int journal_file_next_entry(JournalFile *f, Object *o, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
 179 int journal_file_skip_entry(JournalFile *f, Object *o, uint64_t p, int64_t skip, Object **ret, uint64_t *offset);
 180
 181 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);
 182
 183 int journal_file_move_to_entry_by_offset(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
 184 int journal_file_move_to_entry_by_seqnum(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
 185 int journal_file_move_to_entry_by_realtime(JournalFile *f, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
 186 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);
 187
 188 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);
 189 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);
 190 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);
 191 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);
 192
 193 int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset);
 194
 195 void journal_file_dump(JournalFile *f);
 196 void journal_file_print_header(JournalFile *f);
 197
 198 int journal_file_rotate(JournalFile **f, bool compress, bool seal);
 199
 200 void journal_file_post_change(JournalFile *f);
 201
 202 void journal_default_metrics(JournalMetrics *m, int fd);
 203
 204 int journal_file_get_cutoff_realtime_usec(JournalFile *f, usec_t *from, usec_t *to);
 205 int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot, usec_t *from, usec_t *to);
 206
 207 bool journal_file_rotate_suggested(JournalFile *f, usec_t max_file_usec);
 208
 209
 210 static unsigned type_to_context(int type) {
 211         /* One context for each type, plus one catch-all for the rest */
 212         return type > 0 && type < _OBJECT_TYPE_MAX ? type : 0;
 213 }
 214
 215 static inline int journal_file_object_keep(JournalFile *f, Object *o, uint64_t offset) {
 216         unsigned context = type_to_context(o->object.type);
 217         uint64_t s = le64toh(o->object.size);
 218
 219         return mmap_cache_get(f->mmap, f->fd, f->prot, context, true,
 220                               offset, s, &f->last_stat, NULL);
 221 }
 222
 223 static inline int journal_file_object_release(JournalFile *f, Object *o, uint64_t offset) {
 224         unsigned context = type_to_context(o->object.type);
 225         uint64_t s = le64toh(o->object.size);
 226
 227         return mmap_cache_release(f->mmap, f->fd, f->prot, context, offset, s);
 228 }