chiark / gitweb /
journal: add superficial structure verifier
[elogind.git] / src / journal / journal-file.c
index 7dd7256630c140d51497bf434b1e33218cc76dc8..7beedb4a254cc4edebd8025d5c6fd8489515ab4c 100644 (file)
@@ -36,8 +36,6 @@
 #define DEFAULT_DATA_HASH_TABLE_SIZE (2047ULL*sizeof(HashItem))
 #define DEFAULT_FIELD_HASH_TABLE_SIZE (333ULL*sizeof(HashItem))
 
-#define DEFAULT_WINDOW_SIZE (8ULL*1024ULL*1024ULL)
-
 #define COMPRESSION_SIZE_THRESHOLD (512ULL)
 
 /* This is the minimum journal file size */
@@ -71,8 +69,6 @@ static int journal_file_maybe_append_tag(JournalFile *f, uint64_t realtime);
 static int journal_file_hmac_put_object(JournalFile *f, int type, uint64_t p);
 
 void journal_file_close(JournalFile *f) {
-        int t;
-
         assert(f);
 
         /* Write the final tag */
@@ -80,9 +76,8 @@ void journal_file_close(JournalFile *f) {
                 journal_file_append_tag(f);
 
         /* Sync everything to disk, before we mark the file offline */
-        for (t = 0; t < _WINDOW_MAX; t++)
-                if (f->windows[t].ptr)
-                        munmap(f->windows[t].ptr, f->windows[t].size);
+        if (f->mmap && f->fd >= 0)
+                mmap_cache_close_fd(f->mmap, f->fd);
 
         if (f->writable && f->fd >= 0)
                 fdatasync(f->fd);
@@ -100,6 +95,9 @@ void journal_file_close(JournalFile *f) {
 
         free(f->path);
 
+        if (f->mmap)
+                mmap_cache_unref(f->mmap);
+
 #ifdef HAVE_XZ
         free(f->compress_buffer);
 #endif
@@ -138,7 +136,7 @@ static int journal_file_init_header(JournalFile *f, JournalFile *template) {
 
         if (template) {
                 h.seqnum_id = template->header->seqnum_id;
-                h.tail_seqnum = template->header->tail_seqnum;
+                h.tail_entry_seqnum = template->header->tail_entry_seqnum;
         } else
                 h.seqnum_id = h.file_id;
 
@@ -212,6 +210,10 @@ static int journal_file_verify_header(JournalFile *f) {
         if (le64toh(f->header->header_size) < HEADER_SIZE_MIN)
                 return -EBADMSG;
 
+        if ((le32toh(f->header->compatible_flags) & HEADER_COMPATIBLE_AUTHENTICATED) &&
+                !JOURNAL_HEADER_CONTAINS(f->header, n_tags))
+                return -EBADMSG;
+
         if ((uint64_t) f->last_stat.st_size < (le64toh(f->header->header_size) + le64toh(f->header->arena_size)))
                 return -ENODATA;
 
@@ -297,6 +299,8 @@ static int journal_file_allocate(JournalFile *f, uint64_t offset, uint64_t size)
         if (r != 0)
                 return -r;
 
+        mmap_cache_close_fd_range(f->mmap, f->fd, old_size);
+
         if (fstat(f->fd, &f->last_stat) < 0)
                 return -errno;
 
@@ -305,59 +309,11 @@ static int journal_file_allocate(JournalFile *f, uint64_t offset, uint64_t size)
         return 0;
 }
 
-static int journal_file_map(
-                JournalFile *f,
-                uint64_t offset,
-                uint64_t size,
-                void **_window,
-                uint64_t *_woffset,
-                uint64_t *_wsize,
-                void **ret) {
-
-        uint64_t woffset, wsize;
-        void *window;
-
+static int journal_file_move_to(JournalFile *f, int context, uint64_t offset, uint64_t size, void **ret) {
         assert(f);
-        assert(size > 0);
         assert(ret);
 
-        woffset = offset & ~((uint64_t) page_size() - 1ULL);
-        wsize = size + (offset - woffset);
-        wsize = PAGE_ALIGN(wsize);
-
         /* Avoid SIGBUS on invalid accesses */
-        if (woffset + wsize > (uint64_t) PAGE_ALIGN(f->last_stat.st_size))
-                return -EADDRNOTAVAIL;
-
-        window = mmap(NULL, wsize, f->prot, MAP_SHARED, f->fd, woffset);
-        if (window == MAP_FAILED)
-                return -errno;
-
-        if (_window)
-                *_window = window;
-
-        if (_woffset)
-                *_woffset = woffset;
-
-        if (_wsize)
-                *_wsize = wsize;
-
-        *ret = (uint8_t*) window + (offset - woffset);
-
-        return 0;
-}
-
-static int journal_file_move_to(JournalFile *f, int wt, uint64_t offset, uint64_t size, void **ret) {
-        void *p = NULL;
-        uint64_t delta;
-        int r;
-        Window *w;
-
-        assert(f);
-        assert(ret);
-        assert(wt >= 0);
-        assert(wt < _WINDOW_MAX);
-
         if (offset + size > (uint64_t) f->last_stat.st_size) {
                 /* Hmm, out of range? Let's refresh the fstat() data
                  * first, before we trust that check. */
@@ -367,57 +323,7 @@ static int journal_file_move_to(JournalFile *f, int wt, uint64_t offset, uint64_
                         return -EADDRNOTAVAIL;
         }
 
-        w = f->windows + wt;
-
-        if (_likely_(w->ptr &&
-                     w->offset <= offset &&
-                     w->offset + w->size >= offset + size)) {
-
-                *ret = (uint8_t*) w->ptr + (offset - w->offset);
-                return 0;
-        }
-
-        if (w->ptr) {
-                if (munmap(w->ptr, w->size) < 0)
-                        return -errno;
-
-                w->ptr = NULL;
-                w->size = w->offset = 0;
-        }
-
-        if (size < DEFAULT_WINDOW_SIZE) {
-                /* If the default window size is larger then what was
-                 * asked for extend the mapping a bit in the hope to
-                 * minimize needed remappings later on. We add half
-                 * the window space before and half behind the
-                 * requested mapping */
-
-                delta = (DEFAULT_WINDOW_SIZE - size) / 2;
-
-                if (delta > offset)
-                        delta = offset;
-
-                offset -= delta;
-                size = DEFAULT_WINDOW_SIZE;
-        } else
-                delta = 0;
-
-        if (offset + size > (uint64_t) f->last_stat.st_size)
-                size = (uint64_t) f->last_stat.st_size - offset;
-
-        if (size <= 0)
-                return -EADDRNOTAVAIL;
-
-        r = journal_file_map(f,
-                             offset, size,
-                             &w->ptr, &w->offset, &w->size,
-                             &p);
-
-        if (r < 0)
-                return r;
-
-        *ret = (uint8_t*) p + delta;
-        return 0;
+        return mmap_cache_get(f->mmap, f->fd, f->prot, context, offset, size, ret);
 }
 
 static bool verify_hash(Object *o) {
@@ -437,17 +343,38 @@ static bool verify_hash(Object *o) {
         return h1 == h2;
 }
 
+static uint64_t minimum_header_size(Object *o) {
+
+        static uint64_t table[] = {
+                [OBJECT_DATA] = sizeof(DataObject),
+                [OBJECT_FIELD] = sizeof(FieldObject),
+                [OBJECT_ENTRY] = sizeof(EntryObject),
+                [OBJECT_DATA_HASH_TABLE] = sizeof(HashTableObject),
+                [OBJECT_FIELD_HASH_TABLE] = sizeof(HashTableObject),
+                [OBJECT_ENTRY_ARRAY] = sizeof(EntryArrayObject),
+                [OBJECT_TAG] = sizeof(TagObject),
+        };
+
+        if (o->object.type >= ELEMENTSOF(table) || table[o->object.type] <= 0)
+                return sizeof(ObjectHeader);
+
+        return table[o->object.type];
+}
+
 int journal_file_move_to_object(JournalFile *f, int type, uint64_t offset, Object **ret) {
         int r;
         void *t;
         Object *o;
         uint64_t s;
+        unsigned context;
 
         assert(f);
         assert(ret);
-        assert(type < _OBJECT_TYPE_MAX);
 
-        r = journal_file_move_to(f, type >= 0 ? type : WINDOW_UNKNOWN, offset, sizeof(ObjectHeader), &t);
+        /* One context for each type, plus one catch-all for the rest */
+        context = type > 0 && type < _OBJECT_TYPE_MAX ? type : 0;
+
+        r = journal_file_move_to(f, context, offset, sizeof(ObjectHeader), &t);
         if (r < 0)
                 return r;
 
@@ -457,6 +384,12 @@ int journal_file_move_to_object(JournalFile *f, int type, uint64_t offset, Objec
         if (s < sizeof(ObjectHeader))
                 return -EBADMSG;
 
+        if (o->object.type <= OBJECT_UNUSED)
+                return -EBADMSG;
+
+        if (s < minimum_header_size(o))
+                return -EBADMSG;
+
         if (type >= 0 && o->object.type != type)
                 return -EBADMSG;
 
@@ -475,12 +408,12 @@ int journal_file_move_to_object(JournalFile *f, int type, uint64_t offset, Objec
         return 0;
 }
 
-static uint64_t journal_file_seqnum(JournalFile *f, uint64_t *seqnum) {
+static uint64_t journal_file_entry_seqnum(JournalFile *f, uint64_t *seqnum) {
         uint64_t r;
 
         assert(f);
 
-        r = le64toh(f->header->tail_seqnum) + 1;
+        r = le64toh(f->header->tail_entry_seqnum) + 1;
 
         if (seqnum) {
                 /* If an external seqnum counter was passed, we update
@@ -493,10 +426,10 @@ static uint64_t journal_file_seqnum(JournalFile *f, uint64_t *seqnum) {
                 *seqnum = r;
         }
 
-        f->header->tail_seqnum = htole64(r);
+        f->header->tail_entry_seqnum = htole64(r);
 
-        if (f->header->head_seqnum == 0)
-                f->header->head_seqnum = htole64(r);
+        if (f->header->head_entry_seqnum == 0)
+                f->header->head_entry_seqnum = htole64(r);
 
         return r;
 }
@@ -508,6 +441,7 @@ static int journal_file_append_object(JournalFile *f, int type, uint64_t size, O
         void *t;
 
         assert(f);
+        assert(type > 0 && type < _OBJECT_TYPE_MAX);
         assert(size >= sizeof(ObjectHeader));
         assert(offset);
         assert(ret);
@@ -613,7 +547,7 @@ static int journal_file_map_data_hash_table(JournalFile *f) {
         s = le64toh(f->header->data_hash_table_size);
 
         r = journal_file_move_to(f,
-                                 WINDOW_DATA_HASH_TABLE,
+                                 OBJECT_DATA_HASH_TABLE,
                                  p, s,
                                  &t);
         if (r < 0)
@@ -634,7 +568,7 @@ static int journal_file_map_field_hash_table(JournalFile *f) {
         s = le64toh(f->header->field_hash_table_size);
 
         r = journal_file_move_to(f,
-                                 WINDOW_FIELD_HASH_TABLE,
+                                 OBJECT_FIELD_HASH_TABLE,
                                  p, s,
                                  &t);
         if (r < 0)
@@ -1050,7 +984,7 @@ static int journal_file_append_entry_internal(
         if (r < 0)
                 return r;
 
-        o->entry.seqnum = htole64(journal_file_seqnum(f, seqnum));
+        o->entry.seqnum = htole64(journal_file_entry_seqnum(f, seqnum));
         memcpy(o->entry.items, items, n_items * sizeof(EntryItem));
         o->entry.realtime = htole64(ts->realtime);
         o->entry.monotonic = htole64(ts->monotonic);
@@ -1905,6 +1839,17 @@ static void *fsprg_state(JournalFile *f) {
         return (uint8_t*) f->fsprg_header + a;
 }
 
+static uint64_t journal_file_tag_seqnum(JournalFile *f) {
+        uint64_t r;
+
+        assert(f);
+
+        r = le64toh(f->header->n_tags) + 1;
+        f->header->n_tags = htole64(r);
+
+        return r;
+}
+
 int journal_file_append_tag(JournalFile *f) {
         Object *o;
         uint64_t p;
@@ -1926,6 +1871,14 @@ int journal_file_append_tag(JournalFile *f) {
         if (r < 0)
                 return r;
 
+        o->tag.seqnum = htole64(journal_file_tag_seqnum(f));
+
+        /* Add the tag object itself, so that we can protect its
+         * header. This will exclude the actual hash value in it */
+        r = journal_file_hmac_put_object(f, OBJECT_TAG, p);
+        if (r < 0)
+                return r;
+
         /* Get the HMAC tag and store it in the object */
         memcpy(o->tag.tag, gcry_md_read(f->hmac, 0), TAG_LENGTH);
         f->hmac_running = false;
@@ -2071,8 +2024,8 @@ static int journal_file_hmac_put_object(JournalFile *f, int type, uint64_t p) {
         switch (o->object.type) {
 
         case OBJECT_DATA:
-                /* All but: entry_array_offset, n_entries are mutable */
-                gcry_md_write(f->hmac, &o->data.hash, offsetof(DataObject, entry_array_offset) - offsetof(DataObject, hash));
+                /* All but: hash and payload are mutable */
+                gcry_md_write(f->hmac, &o->data.hash, sizeof(o->data.hash));
                 gcry_md_write(f->hmac, o->data.payload, le64toh(o->object.size) - offsetof(DataObject, payload));
                 break;
 
@@ -2088,10 +2041,9 @@ static int journal_file_hmac_put_object(JournalFile *f, int type, uint64_t p) {
                 break;
 
         case OBJECT_TAG:
-                /* All */
-                gcry_md_write(f->hmac, o->tag.tag, le64toh(o->object.size) - offsetof(TagObject, tag));
+                /* All but the tag itself */
+                gcry_md_write(f->hmac, &o->tag.seqnum, sizeof(o->tag.seqnum));
                 break;
-
         default:
                 return -EINVAL;
         }
@@ -2120,7 +2072,7 @@ static int journal_file_hmac_put_header(JournalFile *f) {
         gcry_md_write(f->hmac, &f->header->file_id, offsetof(Header, boot_id) - offsetof(Header, file_id));
         gcry_md_write(f->hmac, &f->header->seqnum_id, offsetof(Header, arena_size) - offsetof(Header, seqnum_id));
         gcry_md_write(f->hmac, &f->header->data_hash_table_offset, offsetof(Header, tail_object_offset) - offsetof(Header, data_hash_table_offset));
-        gcry_md_write(f->hmac, &f->header->head_seqnum, offsetof(Header, head_entry_realtime) - offsetof(Header, head_seqnum));
+        gcry_md_write(f->hmac, &f->header->head_entry_seqnum, offsetof(Header, head_entry_realtime) - offsetof(Header, head_entry_seqnum));
 
         return 0;
 }
@@ -2277,6 +2229,533 @@ static int journal_file_append_first_tag(JournalFile *f) {
         return 0;
 }
 
+static int journal_file_object_verify(JournalFile *f, Object *o) {
+        assert(f);
+        assert(o);
+
+        /* This does various superficial tests about the length an
+         * possible field values. It does not follow any references to
+         * other objects. */
+
+        switch (o->object.type) {
+        case OBJECT_DATA:
+                if (le64toh(o->data.entry_offset) <= 0 ||
+                    le64toh(o->data.n_entries) <= 0)
+                        return -EBADMSG;
+
+                if (le64toh(o->object.size) - offsetof(DataObject, payload) <= 0)
+                        return -EBADMSG;
+                break;
+
+        case OBJECT_FIELD:
+                if (le64toh(o->object.size) - offsetof(FieldObject, payload) <= 0)
+                        return -EBADMSG;
+                break;
+
+        case OBJECT_ENTRY:
+                if ((le64toh(o->object.size) - offsetof(EntryObject, items)) % sizeof(EntryItem) != 0)
+                        return -EBADMSG;
+
+                if ((le64toh(o->object.size) - offsetof(EntryObject, items)) / sizeof(EntryItem) <= 0)
+                        return -EBADMSG;
+
+                if (le64toh(o->entry.seqnum) <= 0 ||
+                    le64toh(o->entry.realtime) <= 0)
+                        return -EBADMSG;
+
+                break;
+
+        case OBJECT_DATA_HASH_TABLE:
+        case OBJECT_FIELD_HASH_TABLE:
+                if ((le64toh(o->object.size) - offsetof(HashTableObject, items)) % sizeof(HashItem) != 0)
+                        return -EBADMSG;
+
+                break;
+
+        case OBJECT_ENTRY_ARRAY:
+                if ((le64toh(o->object.size) - offsetof(EntryArrayObject, items)) % sizeof(le64_t) != 0)
+                        return -EBADMSG;
+
+                break;
+
+        case OBJECT_TAG:
+                if (le64toh(o->object.size) != sizeof(TagObject))
+                        return -EBADMSG;
+                break;
+        }
+
+        return 0;
+}
+
+static void draw_progress(uint64_t p, usec_t *last_usec) {
+        unsigned n, i, j, k;
+        usec_t z, x;
+
+        if (!isatty(STDOUT_FILENO))
+                return;
+
+        z = now(CLOCK_MONOTONIC);
+        x = *last_usec;
+
+        if (x != 0 && x + 40 * USEC_PER_MSEC > z)
+                return;
+
+        *last_usec = z;
+
+        n = (3 * columns()) / 4;
+        j = (n * (unsigned) p) / 65535ULL;
+        k = n - j;
+
+        fputs("\r\x1B[?25l", stdout);
+
+        for (i = 0; i < j; i++)
+                fputs("\xe2\x96\x88", stdout);
+
+        for (i = 0; i < k; i++)
+                fputs("\xe2\x96\x91", stdout);
+
+        printf(" %3lu%%", 100LU * (unsigned long) p / 65535LU);
+
+        fputs("\r\x1B[?25h", stdout);
+        fflush(stdout);
+}
+
+static void flush_progress(void) {
+        unsigned n, i;
+
+        if (!isatty(STDOUT_FILENO))
+                return;
+
+        n = (3 * columns()) / 4;
+
+        putchar('\r');
+
+        for (i = 0; i < n + 5; i++)
+                putchar(' ');
+
+        putchar('\r');
+        fflush(stdout);
+}
+
+static int write_uint64(int fd, uint64_t p) {
+        ssize_t k;
+
+        k = write(fd, &p, sizeof(p));
+        if (k < 0)
+                return -errno;
+        if (k != sizeof(p))
+                return -EIO;
+
+        return 0;
+}
+
+static int contains_uint64(MMapCache *m, int fd, uint64_t n, uint64_t p) {
+        uint64_t a, b;
+        int r;
+
+        assert(m);
+        assert(fd >= 0);
+
+        /* Bisection ... */
+
+        a = 0; b = n;
+        while (a < b) {
+                uint64_t c, *z;
+
+                c = (a + b) / 2;
+
+                r = mmap_cache_get(m, fd, PROT_READ, 0, c * sizeof(uint64_t), sizeof(uint64_t), (void **) &z);
+                if (r < 0)
+                        return r;
+
+                if (*z == p)
+                        return 1;
+
+                if (p < *z)
+                        b = c;
+                else
+                        a = c;
+        }
+
+        return 0;
+}
+
+int journal_file_verify(JournalFile *f, const char *key) {
+        int r;
+        Object *o;
+        uint64_t p = 0;
+        uint64_t tag_seqnum = 0, entry_seqnum = 0, entry_monotonic = 0, entry_realtime = 0;
+        sd_id128_t entry_boot_id;
+        bool entry_seqnum_set = false, entry_monotonic_set = false, entry_realtime_set = false, found_main_entry_array = false;
+        uint64_t n_weird = 0, n_objects = 0, n_entries = 0, n_data = 0, n_fields = 0, n_data_hash_tables = 0, n_field_hash_tables = 0, n_entry_arrays = 0;
+        usec_t last_usec = 0;
+        int data_fd = -1, entry_fd = -1, entry_array_fd = -1;
+        char data_path[] = "/var/tmp/journal-data-XXXXXX",
+                entry_path[] = "/var/tmp/journal-entry-XXXXXX",
+                entry_array_path[] = "/var/tmp/journal-entry-array-XXXXXX";
+
+        assert(f);
+
+        data_fd = mkostemp(data_path, O_CLOEXEC);
+        if (data_fd < 0) {
+                log_error("Failed to create data file: %m");
+                goto fail;
+        }
+        unlink(data_path);
+
+        entry_fd = mkostemp(entry_path, O_CLOEXEC);
+        if (entry_fd < 0) {
+                log_error("Failed to create entry file: %m");
+                goto fail;
+        }
+        unlink(entry_path);
+
+        entry_array_fd = mkostemp(entry_array_path, O_CLOEXEC);
+        if (entry_array_fd < 0) {
+                log_error("Failed to create entry array file: %m");
+                goto fail;
+        }
+        unlink(entry_array_path);
+
+        /* First iteration: we go through all objects, verify the
+         * superficial structure, headers, hashes. */
+
+        r = journal_file_hmac_put_header(f);
+        if (r < 0) {
+                log_error("Failed to calculate HMAC of header.");
+                goto fail;
+        }
+
+        p = le64toh(f->header->header_size);
+        while (p != 0) {
+                draw_progress((0x7FFF * p) / le64toh(f->header->tail_object_offset), &last_usec);
+
+                r = journal_file_move_to_object(f, -1, p, &o);
+                if (r < 0) {
+                        log_error("Invalid object at %llu", (unsigned long long) p);
+                        goto fail;
+                }
+
+                if (le64toh(f->header->tail_object_offset) < p) {
+                        log_error("Invalid tail object pointer.");
+                        r = -EBADMSG;
+                        goto fail;
+                }
+
+                n_objects ++;
+
+                r = journal_file_object_verify(f, o);
+                if (r < 0) {
+                        log_error("Invalid object contents at %llu", (unsigned long long) p);
+                        goto fail;
+                }
+
+                r = journal_file_hmac_put_object(f, -1, p);
+                if (r < 0) {
+                        log_error("Failed to calculate HMAC at %llu", (unsigned long long) p);
+                        goto fail;
+                }
+
+                if (o->object.flags & OBJECT_COMPRESSED &&
+                    !(le32toh(f->header->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED)) {
+                        log_error("Compressed object without compression at %llu", (unsigned long long) p);
+                        r = -EBADMSG;
+                        goto fail;
+                }
+
+                if (o->object.flags & OBJECT_COMPRESSED &&
+                    o->object.type != OBJECT_DATA) {
+                        log_error("Compressed non-data object at %llu", (unsigned long long) p);
+                        r = -EBADMSG;
+                        goto fail;
+                }
+
+                if (o->object.type == OBJECT_TAG) {
+
+                        if (!(le32toh(f->header->compatible_flags) & HEADER_COMPATIBLE_AUTHENTICATED)) {
+                                log_error("Tag object without authentication at %llu", (unsigned long long) p);
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
+                        if (le64toh(o->tag.seqnum) != tag_seqnum) {
+                                log_error("Tag sequence number out of synchronization at %llu", (unsigned long long) p);
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
+                } else if (o->object.type == OBJECT_ENTRY) {
+
+                        r = write_uint64(entry_fd, p);
+                        if (r < 0)
+                                goto fail;
+
+                        if (!entry_seqnum_set &&
+                            le64toh(o->entry.seqnum) != le64toh(f->header->head_entry_seqnum)) {
+                                log_error("Head entry sequence number incorrect");
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
+                        if (entry_seqnum_set &&
+                            entry_seqnum >= le64toh(o->entry.seqnum)) {
+                                log_error("Entry sequence number out of synchronization at %llu", (unsigned long long) p);
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
+                        entry_seqnum = le64toh(o->entry.seqnum);
+                        entry_seqnum_set = true;
+
+                        if (entry_monotonic_set &&
+                            sd_id128_equal(entry_boot_id, o->entry.boot_id) &&
+                            entry_monotonic > le64toh(o->entry.monotonic)) {
+                                log_error("Entry timestamp out of synchronization at %llu", (unsigned long long) p);
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
+                        entry_monotonic = le64toh(o->entry.monotonic);
+                        entry_boot_id = o->entry.boot_id;
+                        entry_monotonic_set = true;
+
+                        if (!entry_realtime_set &&
+                            le64toh(o->entry.realtime) != le64toh(f->header->head_entry_realtime)) {
+                                log_error("Head entry realtime timestamp incorrect");
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
+                        entry_realtime = le64toh(o->entry.realtime);
+                        entry_realtime_set = true;
+
+                        n_entries ++;
+                } else if (o->object.type == OBJECT_ENTRY_ARRAY) {
+
+                        r = write_uint64(entry_array_fd, p);
+                        if (r < 0)
+                                goto fail;
+
+                        if (p == le64toh(f->header->entry_array_offset)) {
+                                if (found_main_entry_array) {
+                                        log_error("More than one main entry array at %llu", (unsigned long long) p);
+                                        r = -EBADMSG;
+                                        goto fail;
+                                }
+
+                                found_main_entry_array = true;
+                        }
+
+                        n_entry_arrays++;
+
+                } else if (o->object.type == OBJECT_DATA) {
+
+                        r = write_uint64(data_fd, p);
+                        if (r < 0)
+                                goto fail;
+
+                        n_data++;
+
+                } else if (o->object.type == OBJECT_FIELD)
+                        n_fields++;
+                else if (o->object.type == OBJECT_DATA_HASH_TABLE) {
+                        n_data_hash_tables++;
+
+                        if (n_data_hash_tables > 1) {
+                                log_error("More than one data hash table at %llu", (unsigned long long) p);
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
+                        if (le64toh(f->header->data_hash_table_offset) != p + offsetof(HashTableObject, items) ||
+                            le64toh(f->header->data_hash_table_size) != le64toh(o->object.size) - offsetof(HashTableObject, items)) {
+                                log_error("Header fields for data hash table invalid.");
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+                } else if (o->object.type == OBJECT_FIELD_HASH_TABLE) {
+                        n_field_hash_tables++;
+
+                        if (n_field_hash_tables > 1) {
+                                log_error("More than one field hash table at %llu", (unsigned long long) p);
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
+                        if (le64toh(f->header->field_hash_table_offset) != p + offsetof(HashTableObject, items) ||
+                            le64toh(f->header->field_hash_table_size) != le64toh(o->object.size) - offsetof(HashTableObject, items)) {
+                                log_error("Header fields for field hash table invalid.");
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+                } else if (o->object.type >= _OBJECT_TYPE_MAX)
+                        n_weird ++;
+
+                if (p == le64toh(f->header->tail_object_offset))
+                        p = 0;
+                else
+                        p = p + ALIGN64(le64toh(o->object.size));
+        }
+
+        if (n_objects != le64toh(f->header->n_objects)) {
+                log_error("Object number mismatch");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (n_entries != le64toh(f->header->n_entries)) {
+                log_error("Entry number mismatch");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_data) &&
+            n_data != le64toh(f->header->n_data)) {
+                log_error("Data number mismatch");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_fields) &&
+            n_fields != le64toh(f->header->n_fields)) {
+                log_error("Field number mismatch");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_tags) &&
+            tag_seqnum != le64toh(f->header->n_tags)) {
+                log_error("Tag number mismatch");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (n_data_hash_tables != 1) {
+                log_error("Missing data hash table");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (n_field_hash_tables != 1) {
+                log_error("Missing field hash table");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (!found_main_entry_array) {
+                log_error("Missing entry array");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (entry_seqnum_set &&
+            entry_seqnum != le64toh(f->header->tail_entry_seqnum)) {
+                log_error("Invalid tail seqnum");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (entry_monotonic_set &&
+            (!sd_id128_equal(entry_boot_id, f->header->boot_id) ||
+             entry_monotonic != le64toh(f->header->tail_entry_monotonic))) {
+                log_error("Invalid tail monotonic timestamp");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        if (entry_realtime_set && entry_realtime != le64toh(f->header->tail_entry_realtime)) {
+                log_error("Invalid tail realtime timestamp");
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        /* Second iteration: we go through all objects again, this
+         * time verify all pointers. */
+
+        p = le64toh(f->header->header_size);
+        while (p != 0) {
+                draw_progress(0x8000 + (0x7FFF * p) / le64toh(f->header->tail_object_offset), &last_usec);
+
+                r = journal_file_move_to_object(f, -1, p, &o);
+                if (r < 0) {
+                        log_error("Invalid object at %llu", (unsigned long long) p);
+                        goto fail;
+                }
+
+                if (o->object.type == OBJECT_ENTRY_ARRAY) {
+                        uint64_t i = 0, n;
+
+                        if (le64toh(o->entry_array.next_entry_array_offset) != 0 &&
+                            !contains_uint64(f->mmap, entry_array_fd, n_entry_arrays, le64toh(o->entry_array.next_entry_array_offset))) {
+                                log_error("Entry array chains up to invalid next array at %llu", (unsigned long long) p);
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
+                        n = journal_file_entry_array_n_items(o);
+                        for (i = 0; i < n; i++) {
+                                if (le64toh(o->entry_array.items[i]) != 0 &&
+                                    !contains_uint64(f->mmap, entry_fd, n_entries, le64toh(o->entry_array.items[i]))) {
+
+                                        log_error("Entry array points to invalid next array at %llu", (unsigned long long) p);
+                                        r = -EBADMSG;
+                                        goto fail;
+                                }
+                        }
+
+                }
+
+                r = journal_file_move_to_object(f, -1, p, &o);
+                if (r < 0) {
+                        log_error("Invalid object at %llu", (unsigned long long) p);
+                        goto fail;
+                }
+
+                if (p == le64toh(f->header->tail_object_offset))
+                        p = 0;
+                else
+                        p = p + ALIGN64(le64toh(o->object.size));
+        }
+
+        flush_progress();
+
+        mmap_cache_close_fd(f->mmap, data_fd);
+        mmap_cache_close_fd(f->mmap, entry_fd);
+        mmap_cache_close_fd(f->mmap, entry_array_fd);
+
+        close_nointr_nofail(data_fd);
+        close_nointr_nofail(entry_fd);
+        close_nointr_nofail(entry_array_fd);
+
+        return 0;
+
+fail:
+        flush_progress();
+
+        log_error("File corruption detected at %s:%llu (of %llu, %llu%%).",
+                  f->path,
+                  (unsigned long long) p,
+                  (unsigned long long) f->last_stat.st_size,
+                  (unsigned long long) (100 * p / f->last_stat.st_size));
+
+        if (data_fd >= 0) {
+                mmap_cache_close_fd(f->mmap, data_fd);
+                close_nointr_nofail(data_fd);
+        }
+
+        if (entry_fd >= 0) {
+                mmap_cache_close_fd(f->mmap, entry_fd);
+                close_nointr_nofail(entry_fd);
+        }
+
+        if (entry_array_fd >= 0) {
+                mmap_cache_close_fd(f->mmap, entry_array_fd);
+                close_nointr_nofail(entry_array_fd);
+        }
+
+        return r;
+}
+
 void journal_file_dump(JournalFile *f) {
         Object *o;
         int r;
@@ -2322,7 +2801,8 @@ void journal_file_dump(JournalFile *f) {
                         break;
 
                 case OBJECT_TAG:
-                        printf("Type: OBJECT_TAG\n");
+                        printf("Type: OBJECT_TAG %llu\n",
+                               (unsigned long long) le64toh(o->tag.seqnum));
                         break;
                 }
 
@@ -2384,8 +2864,8 @@ void journal_file_print_header(JournalFile *f) {
                (unsigned long long) le64toh(f->header->n_objects),
                (unsigned long long) le64toh(f->header->n_entries),
                yes_no(journal_file_rotate_suggested(f)),
-               (unsigned long long) le64toh(f->header->head_seqnum),
-               (unsigned long long) le64toh(f->header->tail_seqnum),
+               (unsigned long long) le64toh(f->header->head_entry_seqnum),
+               (unsigned long long) le64toh(f->header->tail_entry_seqnum),
                format_timestamp(x, sizeof(x), le64toh(f->header->head_entry_realtime)),
                format_timestamp(y, sizeof(y), le64toh(f->header->tail_entry_realtime)));
 
@@ -2409,6 +2889,7 @@ int journal_file_open(
                 bool compress,
                 bool authenticate,
                 JournalMetrics *metrics,
+                MMapCache *mmap_cache,
                 JournalFile *template,
                 JournalFile **ret) {
 
@@ -2438,6 +2919,19 @@ int journal_file_open(
         f->compress = compress;
         f->authenticate = authenticate;
 
+        if (mmap_cache)
+                f->mmap = mmap_cache_ref(mmap_cache);
+        else {
+                /* One context for each type, plus the zeroth catchall
+                 * context. One fd for the file plus one for each type
+                 * (which we need during verification */
+                f->mmap = mmap_cache_new(_OBJECT_TYPE_MAX, 1 + _OBJECT_TYPE_MAX);
+                if (!f->mmap) {
+                        r = -ENOMEM;
+                        goto fail;
+                }
+        }
+
         f->path = strdup(fname);
         if (!f->path) {
                 r = -ENOMEM;
@@ -2575,7 +3069,7 @@ int journal_file_rotate(JournalFile **f, bool compress, bool authenticate) {
         sd_id128_to_string(old_file->header->seqnum_id, p + l - 8 + 1);
         snprintf(p + l - 8 + 1 + 32, 1 + 16 + 1 + 16 + 8 + 1,
                  "-%016llx-%016llx.journal",
-                 (unsigned long long) le64toh((*f)->header->tail_seqnum),
+                 (unsigned long long) le64toh((*f)->header->tail_entry_seqnum),
                  (unsigned long long) le64toh((*f)->header->tail_entry_realtime));
 
         r = rename(old_file->path, p);
@@ -2586,7 +3080,7 @@ int journal_file_rotate(JournalFile **f, bool compress, bool authenticate) {
 
         old_file->header->state = STATE_ARCHIVED;
 
-        r = journal_file_open(old_file->path, old_file->flags, old_file->mode, compress, authenticate, NULL, old_file, &new_file);
+        r = journal_file_open(old_file->path, old_file->flags, old_file->mode, compress, authenticate, NULL, old_file->mmap, old_file, &new_file);
         journal_file_close(old_file);
 
         *f = new_file;
@@ -2600,6 +3094,7 @@ int journal_file_open_reliably(
                 bool compress,
                 bool authenticate,
                 JournalMetrics *metrics,
+                MMapCache *mmap,
                 JournalFile *template,
                 JournalFile **ret) {
 
@@ -2607,7 +3102,7 @@ int journal_file_open_reliably(
         size_t l;
         char *p;
 
-        r = journal_file_open(fname, flags, mode, compress, authenticate, metrics, template, ret);
+        r = journal_file_open(fname, flags, mode, compress, authenticate, metrics, mmap, template, ret);
         if (r != -EBADMSG && /* corrupted */
             r != -ENODATA && /* truncated */
             r != -EHOSTDOWN && /* other machine */
@@ -2641,7 +3136,7 @@ int journal_file_open_reliably(
 
         log_warning("File %s corrupted or uncleanly shut down, renaming and replacing.", fname);
 
-        return journal_file_open(fname, flags, mode, compress, authenticate, metrics, template, ret);
+        return journal_file_open(fname, flags, mode, compress, authenticate, metrics, mmap, template, ret);
 }
 
 struct vacuum_info {