X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fjournal%2Fjournal-file.c;h=8dc0a3a669036afdca8260ebf0b25c28989d8dc4;hp=4de1daf6a0b177bed7105fc32ea493cc8da4a95c;hb=b588975fb0292cbb23770d6fc2349f57ab5b0db8;hpb=fd8ee359a014916ac62ae2b58f6736ccb48c6d4e

diff --git a/src/journal/journal-file.c b/src/journal/journal-file.c
index 4de1daf6a..8dc0a3a66 100644
--- a/src/journal/journal-file.c
+++ b/src/journal/journal-file.c
@@ -6,16 +6,16 @@
   Copyright 2011 Lennart Poettering
 
   systemd is free software; you can redistribute it and/or modify it
-  under the terms of the GNU General Public License as published by
-  the Free Software Foundation; either version 2 of the License, or
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
   (at your option) any later version.
 
   systemd is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-  General Public License for more details.
+  Lesser General Public License for more details.
 
-  You should have received a copy of the GNU General Public License
+  You should have received a copy of the GNU Lesser General Public License
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
@@ -29,18 +29,18 @@
 
 #include "journal-def.h"
 #include "journal-file.h"
+#include "journal-authenticate.h"
 #include "lookup3.h"
 #include "compress.h"
+#include "fsprg.h"
 
-#define DEFAULT_DATA_HASH_TABLE_SIZE (2047ULL*16ULL)
-#define DEFAULT_FIELD_HASH_TABLE_SIZE (2047ULL*16ULL)
+#define DEFAULT_DATA_HASH_TABLE_SIZE (2047ULL*sizeof(HashItem))
+#define DEFAULT_FIELD_HASH_TABLE_SIZE (333ULL*sizeof(HashItem))
 
-#define DEFAULT_WINDOW_SIZE (128ULL*1024ULL*1024ULL)
-
-#define COMPRESSION_SIZE_THRESHOLD (64ULL)
+#define COMPRESSION_SIZE_THRESHOLD (512ULL)
 
 /* This is the minimum journal file size */
-#define JOURNAL_FILE_SIZE_MIN (64ULL*1024ULL)
+#define JOURNAL_FILE_SIZE_MIN (64ULL*1024ULL)                  /* 64 KiB */
 
 /* These are the lower and upper bounds if we deduce the max_use value
  * from the file system size */
@@ -48,7 +48,7 @@
 #define DEFAULT_MAX_USE_UPPER (4ULL*1024ULL*1024ULL*1024ULL)   /* 4 GiB */
 
 /* This is the upper bound if we deduce max_size from max_use */
-#define DEFAULT_MAX_SIZE_UPPER (16ULL*1024ULL*1024ULL)         /* 16 MiB */
+#define DEFAULT_MAX_SIZE_UPPER (128ULL*1024ULL*1024ULL)        /* 128 MiB */
 
 /* This is the upper bound if we deduce the keep_free value from the
  * file system size */
@@ -58,32 +58,57 @@
  * size */
 #define DEFAULT_KEEP_FREE (1024ULL*1024ULL)                    /* 1 MB */
 
-static const char signature[] = { 'L', 'P', 'K', 'S', 'H', 'H', 'R', 'H' };
-
-#define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
+/* n_data was the first entry we added after the initial file format design */
+#define HEADER_SIZE_MIN ALIGN64(offsetof(Header, n_data))
 
 void journal_file_close(JournalFile *f) {
-        int t;
-
         assert(f);
 
-        if (f->header && f->writable)
-                f->header->state = STATE_OFFLINE;
+#ifdef HAVE_GCRYPT
+        /* Write the final tag */
+        if (f->seal && f->writable)
+                journal_file_append_tag(f);
+#endif
+
+        /* Sync everything to disk, before we mark the file offline */
+        if (f->mmap && f->fd >= 0)
+                mmap_cache_close_fd(f->mmap, f->fd);
+
+        if (f->writable && f->fd >= 0)
+                fdatasync(f->fd);
 
+        if (f->header) {
+                /* Mark the file offline. Don't override the archived state if it already is set */
+                if (f->writable && f->header->state == STATE_ONLINE)
+                        f->header->state = STATE_OFFLINE;
 
-        for (t = 0; t < _WINDOW_MAX; t++)
-                if (f->windows[t].ptr)
-                        munmap(f->windows[t].ptr, f->windows[t].size);
+                munmap(f->header, PAGE_ALIGN(sizeof(Header)));
+        }
 
         if (f->fd >= 0)
                 close_nointr_nofail(f->fd);
 
         free(f->path);
 
+        if (f->mmap)
+                mmap_cache_unref(f->mmap);
+
 #ifdef HAVE_XZ
         free(f->compress_buffer);
 #endif
 
+#ifdef HAVE_GCRYPT
+        if (f->fss_file)
+                munmap(f->fss_file, PAGE_ALIGN(f->fss_file_size));
+        else if (f->fsprg_state)
+                free(f->fsprg_state);
+
+        free(f->fsprg_seed);
+
+        if (f->hmac)
+                gcry_md_close(f->hmac);
+#endif
+
         free(f);
 }
 
@@ -95,8 +120,14 @@ static int journal_file_init_header(JournalFile *f, JournalFile *template) {
         assert(f);
 
         zero(h);
-        memcpy(h.signature, signature, 8);
-        h.arena_offset = htole64(ALIGN64(sizeof(h)));
+        memcpy(h.signature, HEADER_SIGNATURE, 8);
+        h.header_size = htole64(ALIGN64(sizeof(h)));
+
+        h.incompatible_flags =
+                htole32(f->compress ? HEADER_INCOMPATIBLE_COMPRESSED : 0);
+
+        h.compatible_flags =
+                htole32(f->seal ? HEADER_COMPATIBLE_SEALED : 0);
 
         r = sd_id128_randomize(&h.file_id);
         if (r < 0)
@@ -104,7 +135,7 @@ static int journal_file_init_header(JournalFile *f, JournalFile *template) {
 
         if (template) {
                 h.seqnum_id = template->header->seqnum_id;
-                h.seqnum = template->header->seqnum;
+                h.tail_entry_seqnum = template->header->tail_entry_seqnum;
         } else
                 h.seqnum_id = h.file_id;
 
@@ -139,7 +170,9 @@ static int journal_file_refresh_header(JournalFile *f) {
 
         f->header->state = STATE_ONLINE;
 
-        __sync_synchronize();
+        /* Sync the online state to disk */
+        msync(f->header, PAGE_ALIGN(sizeof(Header)), MS_SYNC);
+        fdatasync(f->fd);
 
         return 0;
 }
@@ -147,22 +180,61 @@ static int journal_file_refresh_header(JournalFile *f) {
 static int journal_file_verify_header(JournalFile *f) {
         assert(f);
 
-        if (memcmp(f->header, signature, 8))
+        if (memcmp(f->header->signature, HEADER_SIGNATURE, 8))
                 return -EBADMSG;
 
+        /* In both read and write mode we refuse to open files with
+         * incompatible flags we don't know */
 #ifdef HAVE_XZ
-        if ((le64toh(f->header->incompatible_flags) & ~HEADER_INCOMPATIBLE_COMPRESSED) != 0)
+        if ((le32toh(f->header->incompatible_flags) & ~HEADER_INCOMPATIBLE_COMPRESSED) != 0)
                 return -EPROTONOSUPPORT;
 #else
         if (f->header->incompatible_flags != 0)
                 return -EPROTONOSUPPORT;
 #endif
 
-        if ((uint64_t) f->last_stat.st_size < (le64toh(f->header->arena_offset) + le64toh(f->header->arena_size)))
+        /* When open for writing we refuse to open files with
+         * compatible flags, too */
+        if (f->writable) {
+#ifdef HAVE_GCRYPT
+                if ((le32toh(f->header->compatible_flags) & ~HEADER_COMPATIBLE_SEALED) != 0)
+                        return -EPROTONOSUPPORT;
+#else
+                if (f->header->compatible_flags != 0)
+                        return -EPROTONOSUPPORT;
+#endif
+        }
+
+        if (f->header->state >= _STATE_MAX)
+                return -EBADMSG;
+
+        /* The first addition was n_data, so check that we are at least this large */
+        if (le64toh(f->header->header_size) < HEADER_SIZE_MIN)
+                return -EBADMSG;
+
+        if (JOURNAL_HEADER_SEALED(f->header) && !JOURNAL_HEADER_CONTAINS(f->header, n_entry_arrays))
+                return -EBADMSG;
+
+        if ((le64toh(f->header->header_size) + le64toh(f->header->arena_size)) > (uint64_t) f->last_stat.st_size)
+                return -ENODATA;
+
+        if (le64toh(f->header->tail_object_offset) > (le64toh(f->header->header_size) + le64toh(f->header->arena_size)))
+                return -ENODATA;
+
+        if (!VALID64(le64toh(f->header->data_hash_table_offset)) ||
+            !VALID64(le64toh(f->header->field_hash_table_offset)) ||
+            !VALID64(le64toh(f->header->tail_object_offset)) ||
+            !VALID64(le64toh(f->header->entry_array_offset)))
+                return -ENODATA;
+
+        if (le64toh(f->header->data_hash_table_offset) < le64toh(f->header->header_size) ||
+            le64toh(f->header->field_hash_table_offset) < le64toh(f->header->header_size) ||
+            le64toh(f->header->tail_object_offset) < le64toh(f->header->header_size) ||
+            le64toh(f->header->entry_array_offset) < le64toh(f->header->header_size))
                 return -ENODATA;
 
         if (f->writable) {
-                uint32_t state;
+                uint8_t state;
                 sd_id128_t machine_id;
                 int r;
 
@@ -175,19 +247,28 @@ static int journal_file_verify_header(JournalFile *f) {
 
                 state = f->header->state;
 
-                if (state == STATE_ONLINE)
-                        log_debug("Journal file %s is already online. Assuming unclean closing. Ignoring.", f->path);
-                else if (state == STATE_ARCHIVED)
+                if (state == STATE_ONLINE) {
+                        log_debug("Journal file %s is already online. Assuming unclean closing.", f->path);
+                        return -EBUSY;
+                } else if (state == STATE_ARCHIVED)
                         return -ESHUTDOWN;
-                else if (state != STATE_OFFLINE)
-                        log_debug("Journal file %s has unknown state %u. Ignoring.", f->path, state);
+                else if (state != STATE_OFFLINE) {
+                        log_debug("Journal file %s has unknown state %u.", f->path, state);
+                        return -EBUSY;
+                }
         }
 
+        f->compress = JOURNAL_HEADER_COMPRESSED(f->header);
+
+        if (f->writable)
+                f->seal = JOURNAL_HEADER_SEALED(f->header);
+
         return 0;
 }
 
 static int journal_file_allocate(JournalFile *f, uint64_t offset, uint64_t size) {
         uint64_t old_size, new_size;
+        int r;
 
         assert(f);
 
@@ -196,12 +277,12 @@ static int journal_file_allocate(JournalFile *f, uint64_t offset, uint64_t size)
          * ourselves */
 
         old_size =
-                le64toh(f->header->arena_offset) +
+                le64toh(f->header->header_size) +
                 le64toh(f->header->arena_size);
 
         new_size = PAGE_ALIGN(offset + size);
-        if (new_size < le64toh(f->header->arena_offset))
-                new_size = le64toh(f->header->arena_offset);
+        if (new_size < le64toh(f->header->header_size))
+                new_size = le64toh(f->header->header_size);
 
         if (new_size <= old_size)
                 return 0;
@@ -232,70 +313,26 @@ static int journal_file_allocate(JournalFile *f, uint64_t offset, uint64_t size)
         /* Note that the glibc fallocate() fallback is very
            inefficient, hence we try to minimize the allocation area
            as we can. */
-        if (posix_fallocate(f->fd, old_size, new_size - old_size) < 0)
-                return -errno;
+        r = posix_fallocate(f->fd, old_size, new_size - old_size);
+        if (r != 0)
+                return -r;
 
         if (fstat(f->fd, &f->last_stat) < 0)
                 return -errno;
 
-        f->header->arena_size = new_size - htole64(f->header->arena_offset);
+        f->header->arena_size = htole64(new_size - le64toh(f->header->header_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, bool keep_always, 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);
+        if (size <= 0)
+                return -EINVAL;
 
         /* 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. */
@@ -305,74 +342,25 @@ 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 = PAGE_ALIGN((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 = PAGE_ALIGN((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, keep_always, offset, size, &f->last_stat, ret);
 }
 
-static bool verify_hash(Object *o) {
-        uint64_t h1, h2;
+static uint64_t minimum_header_size(Object *o) {
 
-        assert(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 == OBJECT_DATA && !(o->object.flags & OBJECT_COMPRESSED)) {
-                h1 = le64toh(o->data.hash);
-                h2 = hash64(o->data.payload, le64toh(o->object.size) - offsetof(Object, data.payload));
-        } else if (o->object.type == OBJECT_FIELD) {
-                h1 = le64toh(o->field.hash);
-                h2 = hash64(o->field.payload, le64toh(o->object.size) - offsetof(Object, field.payload));
-        } else
-                return true;
+        if (o->object.type >= ELEMENTSOF(table) || table[o->object.type] <= 0)
+                return sizeof(ObjectHeader);
 
-        return h1 == h2;
+        return table[o->object.type];
 }
 
 int journal_file_move_to_object(JournalFile *f, int type, uint64_t offset, Object **ret) {
@@ -380,12 +368,19 @@ int journal_file_move_to_object(JournalFile *f, int type, uint64_t offset, Objec
         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);
+        /* Objects may only be located at multiple of 64 bit */
+        if (!VALID64(offset))
+                return -EFAULT;
+
+        /* 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, false, offset, sizeof(ObjectHeader), &t);
         if (r < 0)
                 return r;
 
@@ -395,30 +390,33 @@ 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;
 
         if (s > sizeof(ObjectHeader)) {
-                r = journal_file_move_to(f, o->object.type, offset, s, &t);
+                r = journal_file_move_to(f, o->object.type, false, offset, s, &t);
                 if (r < 0)
                         return r;
 
                 o = (Object*) t;
         }
 
-        if (!verify_hash(o))
-                return -EBADMSG;
-
         *ret = o;
         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->seqnum) + 1;
+        r = le64toh(f->header->tail_entry_seqnum) + 1;
 
         if (seqnum) {
                 /* If an external seqnum counter was passed, we update
@@ -431,28 +429,29 @@ static uint64_t journal_file_seqnum(JournalFile *f, uint64_t *seqnum) {
                 *seqnum = r;
         }
 
-        f->header->seqnum = htole64(r);
+        f->header->tail_entry_seqnum = htole64(r);
 
-        if (f->header->first_seqnum == 0)
-                f->header->first_seqnum = htole64(r);
+        if (f->header->head_entry_seqnum == 0)
+                f->header->head_entry_seqnum = htole64(r);
 
         return r;
 }
 
-static int journal_file_append_object(JournalFile *f, int type, uint64_t size, Object **ret, uint64_t *offset) {
+int journal_file_append_object(JournalFile *f, int type, uint64_t size, Object **ret, uint64_t *offset) {
         int r;
         uint64_t p;
         Object *tail, *o;
         void *t;
 
         assert(f);
+        assert(type > 0 && type < _OBJECT_TYPE_MAX);
         assert(size >= sizeof(ObjectHeader));
         assert(offset);
         assert(ret);
 
         p = le64toh(f->header->tail_object_offset);
         if (p == 0)
-                p = le64toh(f->header->arena_offset);
+                p = le64toh(f->header->header_size);
         else {
                 r = journal_file_move_to_object(f, -1, p, &tail);
                 if (r < 0)
@@ -465,7 +464,7 @@ static int journal_file_append_object(JournalFile *f, int type, uint64_t size, O
         if (r < 0)
                 return r;
 
-        r = journal_file_move_to(f, type, p, size, &t);
+        r = journal_file_move_to(f, type, false, p, size, &t);
         if (r < 0)
                 return r;
 
@@ -491,7 +490,17 @@ static int journal_file_setup_data_hash_table(JournalFile *f) {
 
         assert(f);
 
-        s = DEFAULT_DATA_HASH_TABLE_SIZE;
+        /* We estimate that we need 1 hash table entry per 768 of
+           journal file and we want to make sure we never get beyond
+           75% fill level. Calculate the hash table size for the
+           maximum file size based on these metrics. */
+
+        s = (f->metrics.max_size * 4 / 768 / 3) * sizeof(HashItem);
+        if (s < DEFAULT_DATA_HASH_TABLE_SIZE)
+                s = DEFAULT_DATA_HASH_TABLE_SIZE;
+
+        log_debug("Reserving %llu entries in hash table.", (unsigned long long) (s / sizeof(HashItem)));
+
         r = journal_file_append_object(f,
                                        OBJECT_DATA_HASH_TABLE,
                                        offsetof(Object, hash_table.items) + s,
@@ -541,7 +550,8 @@ 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,
+                                 true,
                                  p, s,
                                  &t);
         if (r < 0)
@@ -562,7 +572,8 @@ 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,
+                                 true,
                                  p, s,
                                  &t);
         if (r < 0)
@@ -579,34 +590,37 @@ static int journal_file_link_data(JournalFile *f, Object *o, uint64_t offset, ui
         assert(f);
         assert(o);
         assert(offset > 0);
-        assert(o->object.type == OBJECT_DATA);
+
+        if (o->object.type != OBJECT_DATA)
+                return -EINVAL;
+
+        /* This might alter the window we are looking at */
 
         o->data.next_hash_offset = o->data.next_field_offset = 0;
         o->data.entry_offset = o->data.entry_array_offset = 0;
         o->data.n_entries = 0;
 
         h = hash % (le64toh(f->header->data_hash_table_size) / sizeof(HashItem));
-        p = le64toh(f->data_hash_table[h].head_hash_offset);
+        p = le64toh(f->data_hash_table[h].tail_hash_offset);
         if (p == 0) {
                 /* Only entry in the hash table is easy */
                 f->data_hash_table[h].head_hash_offset = htole64(offset);
         } else {
-                /* Temporarily move back to the previous data object,
-                 * to patch in pointer */
+                /* Move back to the previous data object, to patch in
+                 * pointer */
 
                 r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
                 if (r < 0)
                         return r;
 
                 o->data.next_hash_offset = htole64(offset);
-
-                r = journal_file_move_to_object(f, OBJECT_DATA, offset, &o);
-                if (r < 0)
-                        return r;
         }
 
         f->data_hash_table[h].tail_hash_offset = htole64(offset);
 
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_data))
+                f->header->n_data = htole64(le64toh(f->header->n_data) + 1);
+
         return 0;
 }
 
@@ -614,6 +628,7 @@ int journal_file_find_data_object_with_hash(
                 JournalFile *f,
                 const void *data, uint64_t size, uint64_t hash,
                 Object **ret, uint64_t *offset) {
+
         uint64_t p, osize, h;
         int r;
 
@@ -702,7 +717,11 @@ int journal_file_find_data_object(
                                                        ret, offset);
 }
 
-static int journal_file_append_data(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset) {
+static int journal_file_append_data(
+                JournalFile *f,
+                const void *data, uint64_t size,
+                Object **ret, uint64_t *offset) {
+
         uint64_t hash, p;
         uint64_t osize;
         Object *o;
@@ -746,20 +765,30 @@ static int journal_file_append_data(JournalFile *f, const void *data, uint64_t s
                         o->object.size = htole64(offsetof(Object, data.payload) + rsize);
                         o->object.flags |= OBJECT_COMPRESSED;
 
-                        f->header->incompatible_flags = htole32(le32toh(f->header->incompatible_flags) | HEADER_INCOMPATIBLE_COMPRESSED);
-
                         log_debug("Compressed data object %lu -> %lu", (unsigned long) size, (unsigned long) rsize);
                 }
         }
 #endif
 
-        if (!compressed)
+        if (!compressed && size > 0)
                 memcpy(o->data.payload, data, size);
 
         r = journal_file_link_data(f, o, p, hash);
         if (r < 0)
                 return r;
 
+        /* The linking might have altered the window, so let's
+         * refresh our pointer */
+        r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
+        if (r < 0)
+                return r;
+
+#ifdef HAVE_GCRYPT
+        r = journal_file_hmac_put_object(f, OBJECT_DATA, o, p);
+        if (r < 0)
+                return r;
+#endif
+
         if (ret)
                 *ret = o;
 
@@ -771,21 +800,35 @@ static int journal_file_append_data(JournalFile *f, const void *data, uint64_t s
 
 uint64_t journal_file_entry_n_items(Object *o) {
         assert(o);
-        assert(o->object.type == htole64(OBJECT_ENTRY));
+
+        if (o->object.type != OBJECT_ENTRY)
+                return 0;
 
         return (le64toh(o->object.size) - offsetof(Object, entry.items)) / sizeof(EntryItem);
 }
 
-static uint64_t journal_file_entry_array_n_items(Object *o) {
+uint64_t journal_file_entry_array_n_items(Object *o) {
         assert(o);
-        assert(o->object.type == htole64(OBJECT_ENTRY_ARRAY));
+
+        if (o->object.type != OBJECT_ENTRY_ARRAY)
+                return 0;
 
         return (le64toh(o->object.size) - offsetof(Object, entry_array.items)) / sizeof(uint64_t);
 }
 
+uint64_t journal_file_hash_table_n_items(Object *o) {
+        assert(o);
+
+        if (o->object.type != OBJECT_DATA_HASH_TABLE &&
+            o->object.type != OBJECT_FIELD_HASH_TABLE)
+                return 0;
+
+        return (le64toh(o->object.size) - offsetof(Object, hash_table.items)) / sizeof(HashItem);
+}
+
 static int link_entry_into_array(JournalFile *f,
-                                 uint64_t *first,
-                                 uint64_t *idx,
+                                 le64_t *first,
+                                 le64_t *idx,
                                  uint64_t p) {
         int r;
         uint64_t n = 0, ap = 0, q, i, a, hidx;
@@ -830,10 +873,16 @@ static int link_entry_into_array(JournalFile *f,
         if (r < 0)
                 return r;
 
+#ifdef HAVE_GCRYPT
+        r = journal_file_hmac_put_object(f, OBJECT_ENTRY_ARRAY, o, q);
+        if (r < 0)
+                return r;
+#endif
+
         o->entry_array.items[i] = htole64(p);
 
         if (ap == 0)
-                *first = q;
+                *first = htole64(q);
         else {
                 r = journal_file_move_to_object(f, OBJECT_ENTRY_ARRAY, ap, &o);
                 if (r < 0)
@@ -842,15 +891,18 @@ static int link_entry_into_array(JournalFile *f,
                 o->entry_array.next_entry_array_offset = htole64(q);
         }
 
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_entry_arrays))
+                f->header->n_entry_arrays = htole64(le64toh(f->header->n_entry_arrays) + 1);
+
         *idx = htole64(hidx + 1);
 
         return 0;
 }
 
 static int link_entry_into_array_plus_one(JournalFile *f,
-                                          uint64_t *extra,
-                                          uint64_t *first,
-                                          uint64_t *idx,
+                                          le64_t *extra,
+                                          le64_t *first,
+                                          le64_t *idx,
                                           uint64_t p) {
 
         int r;
@@ -864,9 +916,9 @@ static int link_entry_into_array_plus_one(JournalFile *f,
         if (*idx == 0)
                 *extra = htole64(p);
         else {
-                uint64_t i;
+                le64_t i;
 
-                i = le64toh(*idx) - 1;
+                i = htole64(le64toh(*idx) - 1);
                 r = link_entry_into_array(f, first, &i, p);
                 if (r < 0)
                         return r;
@@ -905,7 +957,9 @@ static int journal_file_link_entry(JournalFile *f, Object *o, uint64_t offset) {
         assert(f);
         assert(o);
         assert(offset > 0);
-        assert(o->object.type == OBJECT_ENTRY);
+
+        if (o->object.type != OBJECT_ENTRY)
+                return -EINVAL;
 
         __sync_synchronize();
 
@@ -917,7 +971,7 @@ static int journal_file_link_entry(JournalFile *f, Object *o, uint64_t offset) {
         if (r < 0)
                 return r;
 
-        log_error("=> %s seqnr=%lu n_entries=%lu", f->path, (unsigned long) o->entry.seqnum, (unsigned long) f->header->n_entries);
+        /* log_debug("=> %s seqnr=%lu n_entries=%lu", f->path, (unsigned long) o->entry.seqnum, (unsigned long) f->header->n_entries); */
 
         if (f->header->head_entry_realtime == 0)
                 f->header->head_entry_realtime = o->entry.realtime;
@@ -960,13 +1014,19 @@ 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);
         o->entry.xor_hash = htole64(xor_hash);
         o->entry.boot_id = f->header->boot_id;
 
+#ifdef HAVE_GCRYPT
+        r = journal_file_hmac_put_object(f, OBJECT_ENTRY, o, np);
+        if (r < 0)
+                return r;
+#endif
+
         r = journal_file_link_entry(f, o, np);
         if (r < 0)
                 return r;
@@ -1016,7 +1076,14 @@ int journal_file_append_entry(JournalFile *f, const dual_timestamp *ts, const st
             ts->monotonic < le64toh(f->header->tail_entry_monotonic))
                 return -EINVAL;
 
-        items = alloca(sizeof(EntryItem) * n_iovec);
+#ifdef HAVE_GCRYPT
+        r = journal_file_maybe_append_tag(f, ts->realtime);
+        if (r < 0)
+                return r;
+#endif
+
+        /* alloca() can't take 0, hence let's allocate at least one */
+        items = alloca(sizeof(EntryItem) * MAX(1, n_iovec));
 
         for (i = 0; i < n_iovec; i++) {
                 uint64_t p;
@@ -1194,8 +1261,15 @@ static int generic_array_bisect(JournalFile *f,
                         }
                 }
 
-                if (k > n)
+                if (k > n) {
+                        if (direction == DIRECTION_UP) {
+                                i = n;
+                                subtract_one = true;
+                                goto found;
+                        }
+
                         return 0;
+                }
 
                 last_p = lp;
 
@@ -1228,7 +1302,7 @@ found:
                 *offset = p;
 
         if (idx)
-                *idx = t + i - (subtract_one ? 1 : 0);
+                *idx = t + i + (subtract_one ? -1 : 0);
 
         return 1;
 }
@@ -1245,6 +1319,8 @@ static int generic_array_bisect_plus_one(JournalFile *f,
                                          uint64_t *idx) {
 
         int r;
+        bool step_back = false;
+        Object *o;
 
         assert(f);
         assert(test_object);
@@ -1257,34 +1333,81 @@ static int generic_array_bisect_plus_one(JournalFile *f,
         r = test_object(f, extra, needle);
         if (r < 0)
                 return r;
-        else if (r == TEST_FOUND) {
-                Object *o;
-
-                r = journal_file_move_to_object(f, OBJECT_ENTRY, extra, &o);
-                if (r < 0)
-                        return r;
-
-                if (ret)
-                        *ret = o;
 
-                if (offset)
-                        *offset = extra;
+        if (r == TEST_FOUND)
+                r = direction == DIRECTION_DOWN ? TEST_RIGHT : TEST_LEFT;
 
-                if (idx)
-                        *idx = 0;
+        /* if we are looking with DIRECTION_UP then we need to first
+           see if in the actual array there is a matching entry, and
+           return the last one of that. But if there isn't any we need
+           to return this one. Hence remember this, and return it
+           below. */
+        if (r == TEST_LEFT)
+                step_back = direction == DIRECTION_UP;
 
-                return 1;
-        } else if (r == TEST_RIGHT)
-                return 0;
+        if (r == TEST_RIGHT) {
+                if (direction == DIRECTION_DOWN)
+                        goto found;
+                else
+                        return 0;
+        }
 
         r = generic_array_bisect(f, first, n-1, needle, test_object, direction, ret, offset, idx);
 
-        if (r > 0)
+        if (r == 0 && step_back)
+                goto found;
+
+        if (r > 0 && idx)
                 (*idx) ++;
 
         return r;
+
+found:
+        r = journal_file_move_to_object(f, OBJECT_ENTRY, extra, &o);
+        if (r < 0)
+                return r;
+
+        if (ret)
+                *ret = o;
+
+        if (offset)
+                *offset = extra;
+
+        if (idx)
+                *idx = 0;
+
+        return 1;
 }
 
+static int test_object_offset(JournalFile *f, uint64_t p, uint64_t needle) {
+        assert(f);
+        assert(p > 0);
+
+        if (p == needle)
+                return TEST_FOUND;
+        else if (p < needle)
+                return TEST_LEFT;
+        else
+                return TEST_RIGHT;
+}
+
+int journal_file_move_to_entry_by_offset(
+                JournalFile *f,
+                uint64_t p,
+                direction_t direction,
+                Object **ret,
+                uint64_t *offset) {
+
+        return generic_array_bisect(f,
+                                    le64toh(f->header->entry_array_offset),
+                                    le64toh(f->header->n_entries),
+                                    p,
+                                    test_object_offset,
+                                    direction,
+                                    ret, offset, NULL);
+}
+
+
 static int test_object_seqnum(JournalFile *f, uint64_t p, uint64_t needle) {
         Object *o;
         int r;
@@ -1382,16 +1505,17 @@ int journal_file_move_to_entry_by_monotonic(
                 Object **ret,
                 uint64_t *offset) {
 
-        char t[8+32+1] = "_BOOT_ID=";
+        char t[9+32+1] = "_BOOT_ID=";
         Object *o;
         int r;
 
-        sd_id128_to_string(boot_id, t + 8);
+        assert(f);
 
+        sd_id128_to_string(boot_id, t + 9);
         r = journal_file_find_data_object(f, t, strlen(t), &o, NULL);
         if (r < 0)
                 return r;
-        else if (r == 0)
+        if (r == 0)
                 return -ENOENT;
 
         return generic_array_bisect_plus_one(f,
@@ -1404,18 +1528,6 @@ int journal_file_move_to_entry_by_monotonic(
                                              ret, offset, NULL);
 }
 
-static int test_object_offset(JournalFile *f, uint64_t p, uint64_t needle) {
-        assert(f);
-        assert(p > 0);
-
-        if (p == needle)
-                return TEST_FOUND;
-        else if (p < needle)
-                return TEST_LEFT;
-        else
-                return TEST_RIGHT;
-}
-
 int journal_file_next_entry(
                 JournalFile *f,
                 Object *o, uint64_t p,
@@ -1580,6 +1692,119 @@ int journal_file_next_entry_for_data(
                                           ret, offset);
 }
 
+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) {
+
+        int r;
+        Object *d;
+
+        assert(f);
+
+        r = journal_file_move_to_object(f, OBJECT_DATA, data_offset, &d);
+        if (r < 0)
+                return r;
+
+        return generic_array_bisect_plus_one(f,
+                                             le64toh(d->data.entry_offset),
+                                             le64toh(d->data.entry_array_offset),
+                                             le64toh(d->data.n_entries),
+                                             p,
+                                             test_object_offset,
+                                             direction,
+                                             ret, offset, NULL);
+}
+
+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) {
+
+        char t[9+32+1] = "_BOOT_ID=";
+        Object *o, *d;
+        int r;
+        uint64_t b, z;
+
+        assert(f);
+
+        /* First, seek by time */
+        sd_id128_to_string(boot_id, t + 9);
+        r = journal_file_find_data_object(f, t, strlen(t), &o, &b);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -ENOENT;
+
+        r = generic_array_bisect_plus_one(f,
+                                          le64toh(o->data.entry_offset),
+                                          le64toh(o->data.entry_array_offset),
+                                          le64toh(o->data.n_entries),
+                                          monotonic,
+                                          test_object_monotonic,
+                                          direction,
+                                          NULL, &z, NULL);
+        if (r <= 0)
+                return r;
+
+        /* And now, continue seeking until we find an entry that
+         * exists in both bisection arrays */
+
+        for (;;) {
+                Object *qo;
+                uint64_t p, q;
+
+                r = journal_file_move_to_object(f, OBJECT_DATA, data_offset, &d);
+                if (r < 0)
+                        return r;
+
+                r = generic_array_bisect_plus_one(f,
+                                                  le64toh(d->data.entry_offset),
+                                                  le64toh(d->data.entry_array_offset),
+                                                  le64toh(d->data.n_entries),
+                                                  z,
+                                                  test_object_offset,
+                                                  direction,
+                                                  NULL, &p, NULL);
+                if (r <= 0)
+                        return r;
+
+                r = journal_file_move_to_object(f, OBJECT_DATA, b, &o);
+                if (r < 0)
+                        return r;
+
+                r = generic_array_bisect_plus_one(f,
+                                                  le64toh(o->data.entry_offset),
+                                                  le64toh(o->data.entry_array_offset),
+                                                  le64toh(o->data.n_entries),
+                                                  p,
+                                                  test_object_offset,
+                                                  direction,
+                                                  &qo, &q, NULL);
+
+                if (r <= 0)
+                        return r;
+
+                if (p == q) {
+                        if (ret)
+                                *ret = qo;
+                        if (offset)
+                                *offset = q;
+
+                        return 1;
+                }
+
+                z = q;
+        }
+
+        return 0;
+}
+
 int journal_file_move_to_entry_by_seqnum_for_data(
                 JournalFile *f,
                 uint64_t data_offset,
@@ -1590,8 +1815,10 @@ int journal_file_move_to_entry_by_seqnum_for_data(
         Object *d;
         int r;
 
+        assert(f);
+
         r = journal_file_move_to_object(f, OBJECT_DATA, data_offset, &d);
-        if (r <= 0)
+        if (r < 0)
                 return r;
 
         return generic_array_bisect_plus_one(f,
@@ -1614,8 +1841,10 @@ int journal_file_move_to_entry_by_realtime_for_data(
         Object *d;
         int r;
 
+        assert(f);
+
         r = journal_file_move_to_object(f, OBJECT_DATA, data_offset, &d);
-        if (r <= 0)
+        if (r < 0)
                 return r;
 
         return generic_array_bisect_plus_one(f,
@@ -1629,29 +1858,15 @@ int journal_file_move_to_entry_by_realtime_for_data(
 }
 
 void journal_file_dump(JournalFile *f) {
-        char a[33], b[33], c[33];
         Object *o;
         int r;
         uint64_t p;
 
         assert(f);
 
-        printf("File Path: %s\n"
-               "File ID: %s\n"
-               "Machine ID: %s\n"
-               "Boot ID: %s\n"
-               "Arena size: %llu\n"
-               "Objects: %lu\n"
-               "Entries: %lu\n",
-               f->path,
-               sd_id128_to_string(f->header->file_id, a),
-               sd_id128_to_string(f->header->machine_id, b),
-               sd_id128_to_string(f->header->boot_id, c),
-               (unsigned long long) le64toh(f->header->arena_size),
-               (unsigned long) le64toh(f->header->n_objects),
-               (unsigned long) le64toh(f->header->n_entries));
+        journal_file_print_header(f);
 
-        p = le64toh(f->header->arena_offset);
+        p = le64toh(f->header->header_size);
         while (p != 0) {
                 r = journal_file_move_to_object(f, -1, p, &o);
                 if (r < 0)
@@ -1668,7 +1883,7 @@ void journal_file_dump(JournalFile *f) {
                         break;
 
                 case OBJECT_ENTRY:
-                        printf("Type: OBJECT_ENTRY %llu %llu %llu\n",
+                        printf("Type: OBJECT_ENTRY seqnum=%llu monotonic=%llu realtime=%llu\n",
                                (unsigned long long) le64toh(o->entry.seqnum),
                                (unsigned long long) le64toh(o->entry.monotonic),
                                (unsigned long long) le64toh(o->entry.realtime));
@@ -1685,6 +1900,12 @@ void journal_file_dump(JournalFile *f) {
                 case OBJECT_ENTRY_ARRAY:
                         printf("Type: OBJECT_ENTRY_ARRAY\n");
                         break;
+
+                case OBJECT_TAG:
+                        printf("Type: OBJECT_TAG seqnum=%llu epoch=%llu\n",
+                               (unsigned long long) le64toh(o->tag.seqnum),
+                               (unsigned long long) le64toh(o->tag.epoch));
+                        break;
                 }
 
                 if (o->object.flags & OBJECT_COMPRESSED)
@@ -1701,10 +1922,88 @@ fail:
         log_error("File corrupt");
 }
 
+void journal_file_print_header(JournalFile *f) {
+        char a[33], b[33], c[33];
+        char x[FORMAT_TIMESTAMP_MAX], y[FORMAT_TIMESTAMP_MAX];
+        struct stat st;
+        char bytes[FORMAT_BYTES_MAX];
+
+        assert(f);
+
+        printf("File Path: %s\n"
+               "File ID: %s\n"
+               "Machine ID: %s\n"
+               "Boot ID: %s\n"
+               "Sequential Number ID: %s\n"
+               "State: %s\n"
+               "Compatible Flags:%s%s\n"
+               "Incompatible Flags:%s%s\n"
+               "Header size: %llu\n"
+               "Arena size: %llu\n"
+               "Data Hash Table Size: %llu\n"
+               "Field Hash Table Size: %llu\n"
+               "Rotate Suggested: %s\n"
+               "Head Sequential Number: %llu\n"
+               "Tail Sequential Number: %llu\n"
+               "Head Realtime Timestamp: %s\n"
+               "Tail Realtime Timestamp: %s\n"
+               "Objects: %llu\n"
+               "Entry Objects: %llu\n",
+               f->path,
+               sd_id128_to_string(f->header->file_id, a),
+               sd_id128_to_string(f->header->machine_id, b),
+               sd_id128_to_string(f->header->boot_id, c),
+               sd_id128_to_string(f->header->seqnum_id, c),
+               f->header->state == STATE_OFFLINE ? "OFFLINE" :
+               f->header->state == STATE_ONLINE ? "ONLINE" :
+               f->header->state == STATE_ARCHIVED ? "ARCHIVED" : "UNKNOWN",
+               JOURNAL_HEADER_SEALED(f->header) ? " SEALED" : "",
+               (le32toh(f->header->compatible_flags) & ~HEADER_COMPATIBLE_SEALED) ? " ???" : "",
+               JOURNAL_HEADER_COMPRESSED(f->header) ? " COMPRESSED" : "",
+               (le32toh(f->header->incompatible_flags) & ~HEADER_INCOMPATIBLE_COMPRESSED) ? " ???" : "",
+               (unsigned long long) le64toh(f->header->header_size),
+               (unsigned long long) le64toh(f->header->arena_size),
+               (unsigned long long) le64toh(f->header->data_hash_table_size) / sizeof(HashItem),
+               (unsigned long long) le64toh(f->header->field_hash_table_size) / sizeof(HashItem),
+               yes_no(journal_file_rotate_suggested(f)),
+               (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)),
+               (unsigned long long) le64toh(f->header->n_objects),
+               (unsigned long long) le64toh(f->header->n_entries));
+
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_data))
+                printf("Data Objects: %llu\n"
+                       "Data Hash Table Fill: %.1f%%\n",
+                       (unsigned long long) le64toh(f->header->n_data),
+                       100.0 * (double) le64toh(f->header->n_data) / ((double) (le64toh(f->header->data_hash_table_size) / sizeof(HashItem))));
+
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_fields))
+                printf("Field Objects: %llu\n"
+                       "Field Hash Table Fill: %.1f%%\n",
+                       (unsigned long long) le64toh(f->header->n_fields),
+                       100.0 * (double) le64toh(f->header->n_fields) / ((double) (le64toh(f->header->field_hash_table_size) / sizeof(HashItem))));
+
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_tags))
+                printf("Tag Objects: %llu\n",
+                       (unsigned long long) le64toh(f->header->n_tags));
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_entry_arrays))
+                printf("Entry Array Objects: %llu\n",
+                       (unsigned long long) le64toh(f->header->n_entry_arrays));
+
+        if (fstat(f->fd, &st) >= 0)
+                printf("Disk usage: %s\n", format_bytes(bytes, sizeof(bytes), (off_t) st.st_blocks * 512ULL));
+}
+
 int journal_file_open(
                 const char *fname,
                 int flags,
                 mode_t mode,
+                bool compress,
+                bool seal,
+                JournalMetrics *metrics,
+                MMapCache *mmap_cache,
                 JournalFile *template,
                 JournalFile **ret) {
 
@@ -1718,15 +2017,36 @@ int journal_file_open(
             (flags & O_ACCMODE) != O_RDWR)
                 return -EINVAL;
 
+        if (!endswith(fname, ".journal") &&
+            !endswith(fname, ".journal~"))
+                return -EINVAL;
+
         f = new0(JournalFile, 1);
         if (!f)
                 return -ENOMEM;
 
         f->fd = -1;
-        f->flags = flags;
         f->mode = mode;
-        f->writable = (flags & O_ACCMODE) != O_RDONLY;
+
+        f->flags = flags;
         f->prot = prot_from_flags(flags);
+        f->writable = (flags & O_ACCMODE) != O_RDONLY;
+#ifdef HAVE_XZ
+        f->compress = compress;
+#endif
+#ifdef HAVE_GCRYPT
+        f->seal = seal;
+#endif
+
+        if (mmap_cache)
+                f->mmap = mmap_cache_ref(mmap_cache);
+        else {
+                f->mmap = mmap_cache_new();
+                if (!f->mmap) {
+                        r = -ENOMEM;
+                        goto fail;
+                }
+        }
 
         f->path = strdup(fname);
         if (!f->path) {
@@ -1748,6 +2068,16 @@ int journal_file_open(
         if (f->last_stat.st_size == 0 && f->writable) {
                 newly_created = true;
 
+#ifdef HAVE_GCRYPT
+                /* Try to load the FSPRG state, and if we can't, then
+                 * just don't do sealing */
+                if (f->seal) {
+                        r = journal_file_fss_load(f);
+                        if (r < 0)
+                                f->seal = false;
+                }
+#endif
+
                 r = journal_file_init_header(f, template);
                 if (r < 0)
                         goto fail;
@@ -1758,7 +2088,7 @@ int journal_file_open(
                 }
         }
 
-        if (f->last_stat.st_size < (off_t) sizeof(Header)) {
+        if (f->last_stat.st_size < (off_t) HEADER_SIZE_MIN) {
                 r = -EIO;
                 goto fail;
         }
@@ -1776,14 +2106,33 @@ int journal_file_open(
                         goto fail;
         }
 
+#ifdef HAVE_GCRYPT
+        if (!newly_created && f->writable) {
+                r = journal_file_fss_load(f);
+                if (r < 0)
+                        goto fail;
+        }
+#endif
+
         if (f->writable) {
+                if (metrics) {
+                        journal_default_metrics(metrics, f->fd);
+                        f->metrics = *metrics;
+                } else if (template)
+                        f->metrics = template->metrics;
+
                 r = journal_file_refresh_header(f);
                 if (r < 0)
                         goto fail;
         }
 
-        if (newly_created) {
+#ifdef HAVE_GCRYPT
+        r = journal_file_hmac_setup(f);
+        if (r < 0)
+                goto fail;
+#endif
 
+        if (newly_created) {
                 r = journal_file_setup_field_hash_table(f);
                 if (r < 0)
                         goto fail;
@@ -1791,6 +2140,12 @@ int journal_file_open(
                 r = journal_file_setup_data_hash_table(f);
                 if (r < 0)
                         goto fail;
+
+#ifdef HAVE_GCRYPT
+                r = journal_file_append_first_tag(f);
+                if (r < 0)
+                        goto fail;
+#endif
         }
 
         r = journal_file_map_field_hash_table(f);
@@ -1812,7 +2167,7 @@ fail:
         return r;
 }
 
-int journal_file_rotate(JournalFile **f) {
+int journal_file_rotate(JournalFile **f, bool compress, bool seal) {
         char *p;
         size_t l;
         JournalFile *old_file, *new_file = NULL;
@@ -1831,7 +2186,7 @@ int journal_file_rotate(JournalFile **f) {
 
         l = strlen(old_file->path);
 
-        p = new(char, l + 1 + 16 + 1 + 32 + 1 + 16 + 1);
+        p = new(char, l + 1 + 32 + 1 + 16 + 1 + 16 + 1);
         if (!p)
                 return -ENOMEM;
 
@@ -1840,7 +2195,7 @@ int journal_file_rotate(JournalFile **f) {
         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->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);
@@ -1849,175 +2204,70 @@ int journal_file_rotate(JournalFile **f) {
         if (r < 0)
                 return -errno;
 
-        old_file->header->state = le32toh(STATE_ARCHIVED);
+        old_file->header->state = STATE_ARCHIVED;
 
-        r = journal_file_open(old_file->path, old_file->flags, old_file->mode, old_file, &new_file);
+        r = journal_file_open(old_file->path, old_file->flags, old_file->mode, compress, seal, NULL, old_file->mmap, old_file, &new_file);
         journal_file_close(old_file);
 
         *f = new_file;
         return r;
 }
 
-struct vacuum_info {
-        off_t usage;
-        char *filename;
-
-        uint64_t realtime;
-        sd_id128_t seqnum_id;
-        uint64_t seqnum;
-};
+int journal_file_open_reliably(
+                const char *fname,
+                int flags,
+                mode_t mode,
+                bool compress,
+                bool seal,
+                JournalMetrics *metrics,
+                MMapCache *mmap_cache,
+                JournalFile *template,
+                JournalFile **ret) {
 
-static int vacuum_compare(const void *_a, const void *_b) {
-        const struct vacuum_info *a, *b;
+        int r;
+        size_t l;
+        char *p;
 
-        a = _a;
-        b = _b;
+        r = journal_file_open(fname, flags, mode, compress, seal,
+                              metrics, mmap_cache, template, ret);
+        if (r != -EBADMSG && /* corrupted */
+            r != -ENODATA && /* truncated */
+            r != -EHOSTDOWN && /* other machine */
+            r != -EPROTONOSUPPORT && /* incompatible feature */
+            r != -EBUSY && /* unclean shutdown */
+            r != -ESHUTDOWN /* already archived */)
+                return r;
 
-        if (sd_id128_equal(a->seqnum_id, b->seqnum_id)) {
-                if (a->seqnum < b->seqnum)
-                        return -1;
-                else if (a->seqnum > b->seqnum)
-                        return 1;
-                else
-                        return 0;
-        }
+        if ((flags & O_ACCMODE) == O_RDONLY)
+                return r;
 
-        if (a->realtime < b->realtime)
-                return -1;
-        else if (a->realtime > b->realtime)
-                return 1;
-        else
-                return memcmp(&a->seqnum_id, &b->seqnum_id, 16);
-}
+        if (!(flags & O_CREAT))
+                return r;
 
-int journal_directory_vacuum(const char *directory, uint64_t max_use, uint64_t min_free) {
-        DIR *d;
-        int r = 0;
-        struct vacuum_info *list = NULL;
-        unsigned n_list = 0, n_allocated = 0, i;
-        uint64_t sum = 0;
+        if (!endswith(fname, ".journal"))
+                return r;
 
-        assert(directory);
+        /* The file is corrupted. Rotate it away and try it again (but only once) */
 
-        if (max_use <= 0)
-                return 0;
+        l = strlen(fname);
+        if (asprintf(&p, "%.*s@%016llx-%016llx.journal~",
+                     (int) (l-8), fname,
+                     (unsigned long long) now(CLOCK_REALTIME),
+                     random_ull()) < 0)
+                return -ENOMEM;
 
-        d = opendir(directory);
-        if (!d)
+        r = rename(fname, p);
+        free(p);
+        if (r < 0)
                 return -errno;
 
-        for (;;) {
-                int k;
-                struct dirent buf, *de;
-                size_t q;
-                struct stat st;
-                char *p;
-                unsigned long long seqnum, realtime;
-                sd_id128_t seqnum_id;
-
-                k = readdir_r(d, &buf, &de);
-                if (k != 0) {
-                        r = -k;
-                        goto finish;
-                }
-
-                if (!de)
-                        break;
-
-                if (!dirent_is_file_with_suffix(de, ".journal"))
-                        continue;
-
-                q = strlen(de->d_name);
-
-                if (q < 1 + 32 + 1 + 16 + 1 + 16 + 8)
-                        continue;
-
-                if (de->d_name[q-8-16-1] != '-' ||
-                    de->d_name[q-8-16-1-16-1] != '-' ||
-                    de->d_name[q-8-16-1-16-1-32-1] != '@')
-                        continue;
-
-                if (fstatat(dirfd(d), de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0)
-                        continue;
-
-                if (!S_ISREG(st.st_mode))
-                        continue;
-
-                p = strdup(de->d_name);
-                if (!p) {
-                        r = -ENOMEM;
-                        goto finish;
-                }
-
-                de->d_name[q-8-16-1-16-1] = 0;
-                if (sd_id128_from_string(de->d_name + q-8-16-1-16-1-32, &seqnum_id) < 0) {
-                        free(p);
-                        continue;
-                }
-
-                if (sscanf(de->d_name + q-8-16-1-16, "%16llx-%16llx.journal", &seqnum, &realtime) != 2) {
-                        free(p);
-                        continue;
-                }
-
-                if (n_list >= n_allocated) {
-                        struct vacuum_info *j;
-
-                        n_allocated = MAX(n_allocated * 2U, 8U);
-                        j = realloc(list, n_allocated * sizeof(struct vacuum_info));
-                        if (!j) {
-                                free(p);
-                                r = -ENOMEM;
-                                goto finish;
-                        }
-
-                        list = j;
-                }
-
-                list[n_list].filename = p;
-                list[n_list].usage = (uint64_t) st.st_blksize * (uint64_t) st.st_blocks;
-                list[n_list].seqnum = seqnum;
-                list[n_list].realtime = realtime;
-                list[n_list].seqnum_id = seqnum_id;
-
-                sum += list[n_list].usage;
-
-                n_list ++;
-        }
-
-        qsort(list, n_list, sizeof(struct vacuum_info), vacuum_compare);
+        log_warning("File %s corrupted or uncleanly shut down, renaming and replacing.", fname);
 
-        for(i = 0; i < n_list; i++) {
-                struct statvfs ss;
-
-                if (fstatvfs(dirfd(d), &ss) < 0) {
-                        r = -errno;
-                        goto finish;
-                }
-
-                if (sum <= max_use &&
-                    (uint64_t) ss.f_bavail * (uint64_t) ss.f_bsize >= min_free)
-                        break;
-
-                if (unlinkat(dirfd(d), list[i].filename, 0) >= 0) {
-                        log_debug("Deleted archived journal %s/%s.", directory, list[i].filename);
-                        sum -= list[i].usage;
-                } else if (errno != ENOENT)
-                        log_warning("Failed to delete %s/%s: %m", directory, list[i].filename);
-        }
-
-finish:
-        for (i = 0; i < n_list; i++)
-                free(list[i].filename);
-
-        free(list);
-
-        if (d)
-                closedir(d);
-
-        return r;
+        return journal_file_open(fname, flags, mode, compress, seal,
+                                 metrics, mmap_cache, template, ret);
 }
 
+
 int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset) {
         uint64_t i, n;
         uint64_t q, xor_hash = 0;
@@ -2040,14 +2290,12 @@ int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint6
             ts.monotonic < le64toh(to->header->tail_entry_monotonic))
                 return -EINVAL;
 
-        if (ts.realtime < le64toh(to->header->tail_entry_realtime))
-                return -EINVAL;
-
         n = journal_file_entry_n_items(o);
         items = alloca(sizeof(EntryItem) * n);
 
         for (i = 0; i < n; i++) {
-                uint64_t le_hash, l, h;
+                uint64_t l, h;
+                le64_t le_hash;
                 size_t t;
                 void *data;
                 Object *u;
@@ -2103,7 +2351,7 @@ int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint6
 void journal_default_metrics(JournalMetrics *m, int fd) {
         uint64_t fs_size = 0;
         struct statvfs ss;
-        char a[64], b[64], c[64], d[64];
+        char a[FORMAT_BYTES_MAX], b[FORMAT_BYTES_MAX], c[FORMAT_BYTES_MAX], d[FORMAT_BYTES_MAX];
 
         assert(m);
         assert(fd >= 0);
@@ -2174,3 +2422,110 @@ void journal_default_metrics(JournalMetrics *m, int fd) {
                   format_bytes(c, sizeof(c), m->min_size),
                   format_bytes(d, sizeof(d), m->keep_free));
 }
+
+int journal_file_get_cutoff_realtime_usec(JournalFile *f, usec_t *from, usec_t *to) {
+        assert(f);
+        assert(from || to);
+
+        if (from) {
+                if (f->header->head_entry_realtime == 0)
+                        return -ENOENT;
+
+                *from = le64toh(f->header->head_entry_realtime);
+        }
+
+        if (to) {
+                if (f->header->tail_entry_realtime == 0)
+                        return -ENOENT;
+
+                *to = le64toh(f->header->tail_entry_realtime);
+        }
+
+        return 1;
+}
+
+int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot_id, usec_t *from, usec_t *to) {
+        char t[9+32+1] = "_BOOT_ID=";
+        Object *o;
+        uint64_t p;
+        int r;
+
+        assert(f);
+        assert(from || to);
+
+        sd_id128_to_string(boot_id, t + 9);
+
+        r = journal_file_find_data_object(f, t, strlen(t), &o, &p);
+        if (r <= 0)
+                return r;
+
+        if (le64toh(o->data.n_entries) <= 0)
+                return 0;
+
+        if (from) {
+                r = journal_file_move_to_object(f, OBJECT_ENTRY, le64toh(o->data.entry_offset), &o);
+                if (r < 0)
+                        return r;
+
+                *from = le64toh(o->entry.monotonic);
+        }
+
+        if (to) {
+                r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
+                if (r < 0)
+                        return r;
+
+                r = generic_array_get_plus_one(f,
+                                               le64toh(o->data.entry_offset),
+                                               le64toh(o->data.entry_array_offset),
+                                               le64toh(o->data.n_entries)-1,
+                                               &o, NULL);
+                if (r <= 0)
+                        return r;
+
+                *to = le64toh(o->entry.monotonic);
+        }
+
+        return 1;
+}
+
+bool journal_file_rotate_suggested(JournalFile *f) {
+        assert(f);
+
+        /* If we gained new header fields we gained new features,
+         * hence suggest a rotation */
+        if (le64toh(f->header->header_size) < sizeof(Header)) {
+                log_debug("%s uses an outdated header, suggesting rotation.", f->path);
+                return true;
+        }
+
+        /* Let's check if the hash tables grew over a certain fill
+         * level (75%, borrowing this value from Java's hash table
+         * implementation), and if so suggest a rotation. To calculate
+         * the fill level we need the n_data field, which only exists
+         * in newer versions. */
+
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_data))
+                if (le64toh(f->header->n_data) * 4ULL > (le64toh(f->header->data_hash_table_size) / sizeof(HashItem)) * 3ULL) {
+                        log_debug("Data hash table of %s has a fill level at %.1f (%llu of %llu items, %llu file size, %llu bytes per hash table item), suggesting rotation.",
+                                  f->path,
+                                  100.0 * (double) le64toh(f->header->n_data) / ((double) (le64toh(f->header->data_hash_table_size) / sizeof(HashItem))),
+                                  (unsigned long long) le64toh(f->header->n_data),
+                                  (unsigned long long) (le64toh(f->header->data_hash_table_size) / sizeof(HashItem)),
+                                  (unsigned long long) (f->last_stat.st_size),
+                                  (unsigned long long) (f->last_stat.st_size / le64toh(f->header->n_data)));
+                        return true;
+                }
+
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_fields))
+                if (le64toh(f->header->n_fields) * 4ULL > (le64toh(f->header->field_hash_table_size) / sizeof(HashItem)) * 3ULL) {
+                        log_debug("Field hash table of %s has a fill level at %.1f (%llu of %llu items), suggesting rotation.",
+                                  f->path,
+                                  100.0 * (double) le64toh(f->header->n_fields) / ((double) (le64toh(f->header->field_hash_table_size) / sizeof(HashItem))),
+                                  (unsigned long long) le64toh(f->header->n_fields),
+                                  (unsigned long long) (le64toh(f->header->field_hash_table_size) / sizeof(HashItem)));
+                        return true;
+                }
+
+        return false;
+}