chiark / gitweb /
journal: add ability to list values a specified field can take in all entries of...
[elogind.git] / src / journal / journal-file.c
index 8bd52733c97db551d04f86cd31cee63a18b0cd3c..43fd4453a44accfde468c66c37f1e236072f43e2 100644 (file)
 #include <fcntl.h>
 #include <stddef.h>
 
+#ifdef HAVE_XATTR
+#include <attr/xattr.h>
+#endif
+
 #include "journal-def.h"
 #include "journal-file.h"
 #include "journal-authenticate.h"
@@ -260,8 +264,7 @@ static int journal_file_verify_header(JournalFile *f) {
 
         f->compress = JOURNAL_HEADER_COMPRESSED(f->header);
 
-        if (f->writable)
-                f->seal = JOURNAL_HEADER_SEALED(f->header);
+        f->seal = JOURNAL_HEADER_SEALED(f->header);
 
         return 0;
 }
@@ -396,7 +399,7 @@ int journal_file_move_to_object(JournalFile *f, int type, uint64_t offset, Objec
         if (s < minimum_header_size(o))
                 return -EBADMSG;
 
-        if (type >= 0 && o->object.type != type)
+        if (type > 0 && o->object.type != type)
                 return -EBADMSG;
 
         if (s > sizeof(ObjectHeader)) {
@@ -523,6 +526,9 @@ static int journal_file_setup_field_hash_table(JournalFile *f) {
 
         assert(f);
 
+        /* We use a fixed size hash table for the fields as this
+         * number should grow very slowly only */
+
         s = DEFAULT_FIELD_HASH_TABLE_SIZE;
         r = journal_file_append_object(f,
                                        OBJECT_FIELD_HASH_TABLE,
@@ -583,14 +589,61 @@ static int journal_file_map_field_hash_table(JournalFile *f) {
         return 0;
 }
 
-static int journal_file_link_data(JournalFile *f, Object *o, uint64_t offset, uint64_t hash) {
+static int journal_file_link_field(
+                JournalFile *f,
+                Object *o,
+                uint64_t offset,
+                uint64_t hash) {
+
         uint64_t p, h;
         int r;
 
         assert(f);
         assert(o);
         assert(offset > 0);
-        assert(o->object.type == OBJECT_DATA);
+
+        if (o->object.type != OBJECT_FIELD)
+                return -EINVAL;
+
+        /* This might alter the window we are looking at */
+
+        o->field.next_hash_offset = o->field.head_data_offset = 0;
+
+        h = hash % (le64toh(f->header->field_hash_table_size) / sizeof(HashItem));
+        p = le64toh(f->field_hash_table[h].tail_hash_offset);
+        if (p == 0)
+                f->field_hash_table[h].head_hash_offset = htole64(offset);
+        else {
+                r = journal_file_move_to_object(f, OBJECT_FIELD, p, &o);
+                if (r < 0)
+                        return r;
+
+                o->field.next_hash_offset = htole64(offset);
+        }
+
+        f->field_hash_table[h].tail_hash_offset = htole64(offset);
+
+        if (JOURNAL_HEADER_CONTAINS(f->header, n_fields))
+                f->header->n_fields = htole64(le64toh(f->header->n_fields) + 1);
+
+        return 0;
+}
+
+static int journal_file_link_data(
+                JournalFile *f,
+                Object *o,
+                uint64_t offset,
+                uint64_t hash) {
+
+        uint64_t p, h;
+        int r;
+
+        assert(f);
+        assert(o);
+        assert(offset > 0);
+
+        if (o->object.type != OBJECT_DATA)
+                return -EINVAL;
 
         /* This might alter the window we are looking at */
 
@@ -600,10 +653,10 @@ static int journal_file_link_data(JournalFile *f, Object *o, uint64_t offset, ui
 
         h = hash % (le64toh(f->header->data_hash_table_size) / sizeof(HashItem));
         p = le64toh(f->data_hash_table[h].tail_hash_offset);
-        if (p == 0) {
+        if (p == 0)
                 /* Only entry in the hash table is easy */
                 f->data_hash_table[h].head_hash_offset = htole64(offset);
-        else {
+        else {
                 /* Move back to the previous data object, to patch in
                  * pointer */
 
@@ -622,6 +675,67 @@ static int journal_file_link_data(JournalFile *f, Object *o, uint64_t offset, ui
         return 0;
 }
 
+int journal_file_find_field_object_with_hash(
+                JournalFile *f,
+                const void *field, uint64_t size, uint64_t hash,
+                Object **ret, uint64_t *offset) {
+
+        uint64_t p, osize, h;
+        int r;
+
+        assert(f);
+        assert(field && size > 0);
+
+        osize = offsetof(Object, field.payload) + size;
+
+        if (f->header->field_hash_table_size == 0)
+                return -EBADMSG;
+
+        h = hash % (le64toh(f->header->field_hash_table_size) / sizeof(HashItem));
+        p = le64toh(f->field_hash_table[h].head_hash_offset);
+
+        while (p > 0) {
+                Object *o;
+
+                r = journal_file_move_to_object(f, OBJECT_FIELD, p, &o);
+                if (r < 0)
+                        return r;
+
+                if (le64toh(o->field.hash) == hash &&
+                    le64toh(o->object.size) == osize &&
+                    memcmp(o->field.payload, field, size) == 0) {
+
+                        if (ret)
+                                *ret = o;
+                        if (offset)
+                                *offset = p;
+
+                        return 1;
+                }
+
+                p = le64toh(o->field.next_hash_offset);
+        }
+
+        return 0;
+}
+
+int journal_file_find_field_object(
+                JournalFile *f,
+                const void *field, uint64_t size,
+                Object **ret, uint64_t *offset) {
+
+        uint64_t hash;
+
+        assert(f);
+        assert(field && size > 0);
+
+        hash = hash64(field, size);
+
+        return journal_file_find_field_object_with_hash(f,
+                                                        field, size, hash,
+                                                        ret, offset);
+}
+
 int journal_file_find_data_object_with_hash(
                 JournalFile *f,
                 const void *data, uint64_t size, uint64_t hash,
@@ -715,6 +829,66 @@ int journal_file_find_data_object(
                                                        ret, offset);
 }
 
+static int journal_file_append_field(
+                JournalFile *f,
+                const void *field, uint64_t size,
+                Object **ret, uint64_t *offset) {
+
+        uint64_t hash, p;
+        uint64_t osize;
+        Object *o;
+        int r;
+
+        assert(f);
+        assert(field && size > 0);
+
+        hash = hash64(field, size);
+
+        r = journal_file_find_field_object_with_hash(f, field, size, hash, &o, &p);
+        if (r < 0)
+                return r;
+        else if (r > 0) {
+
+                if (ret)
+                        *ret = o;
+
+                if (offset)
+                        *offset = p;
+
+                return 0;
+        }
+
+        osize = offsetof(Object, field.payload) + size;
+        r = journal_file_append_object(f, OBJECT_FIELD, osize, &o, &p);
+
+        o->field.hash = htole64(hash);
+        memcpy(o->field.payload, field, size);
+
+        r = journal_file_link_field(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_FIELD, p, &o);
+        if (r < 0)
+                return r;
+
+#ifdef HAVE_GCRYPT
+        r = journal_file_hmac_put_object(f, OBJECT_FIELD, o, p);
+        if (r < 0)
+                return r;
+#endif
+
+        if (ret)
+                *ret = o;
+
+        if (offset)
+                *offset = p;
+
+        return 0;
+}
+
 static int journal_file_append_data(
                 JournalFile *f,
                 const void *data, uint64_t size,
@@ -725,6 +899,7 @@ static int journal_file_append_data(
         Object *o;
         int r;
         bool compressed = false;
+        const void *eq;
 
         assert(f);
         assert(data || size == 0);
@@ -775,18 +950,33 @@ static int journal_file_append_data(
         if (r < 0)
                 return r;
 
-#ifdef HAVE_GCRYPT
-        r = journal_file_hmac_put_object(f, OBJECT_DATA, p);
-        if (r < 0)
-                return r;
-#endif
-
         /* 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;
 
+        eq = memchr(data, '=', size);
+        if (eq && eq > data) {
+                uint64_t fp;
+                Object *fo;
+
+                /* Create field object ... */
+                r = journal_file_append_field(f, data, (uint8_t*) eq - (uint8_t*) data, &fo, &fp);
+                if (r < 0)
+                        return r;
+
+                /* ... and link it in. */
+                o->data.next_field_offset = fo->field.head_data_offset;
+                fo->field.head_data_offset = le64toh(p);
+        }
+
+#ifdef HAVE_GCRYPT
+        r = journal_file_hmac_put_object(f, OBJECT_DATA, o, p);
+        if (r < 0)
+                return r;
+#endif
+
         if (ret)
                 *ret = o;
 
@@ -798,22 +988,28 @@ static int journal_file_append_data(
 
 uint64_t journal_file_entry_n_items(Object *o) {
         assert(o);
-        assert(o->object.type == OBJECT_ENTRY);
+
+        if (o->object.type != OBJECT_ENTRY)
+                return 0;
 
         return (le64toh(o->object.size) - offsetof(Object, entry.items)) / sizeof(EntryItem);
 }
 
 uint64_t journal_file_entry_array_n_items(Object *o) {
         assert(o);
-        assert(o->object.type == 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);
-        assert(o->object.type == OBJECT_DATA_HASH_TABLE ||
-               o->object.type == OBJECT_FIELD_HASH_TABLE);
+
+        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);
 }
@@ -866,7 +1062,7 @@ static int link_entry_into_array(JournalFile *f,
                 return r;
 
 #ifdef HAVE_GCRYPT
-        r = journal_file_hmac_put_object(f, OBJECT_ENTRY_ARRAY, q);
+        r = journal_file_hmac_put_object(f, OBJECT_ENTRY_ARRAY, o, q);
         if (r < 0)
                 return r;
 #endif
@@ -949,7 +1145,9 @@ 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();
 
@@ -1012,7 +1210,7 @@ static int journal_file_append_entry_internal(
         o->entry.boot_id = f->header->boot_id;
 
 #ifdef HAVE_GCRYPT
-        r = journal_file_hmac_put_object(f, OBJECT_ENTRY, np);
+        r = journal_file_hmac_put_object(f, OBJECT_ENTRY, o, np);
         if (r < 0)
                 return r;
 #endif
@@ -1041,7 +1239,17 @@ void journal_file_post_change(JournalFile *f) {
         __sync_synchronize();
 
         if (ftruncate(f->fd, f->last_stat.st_size) < 0)
-                log_error("Failed to to truncate file to its own size: %m");
+                log_error("Failed to truncate file to its own size: %m");
+}
+
+static int entry_item_cmp(const void *_a, const void *_b) {
+        const EntryItem *a = _a, *b = _b;
+
+        if (le64toh(a->object_offset) < le64toh(b->object_offset))
+                return -1;
+        if (le64toh(a->object_offset) > le64toh(b->object_offset))
+                return 1;
+        return 0;
 }
 
 int journal_file_append_entry(JournalFile *f, const dual_timestamp *ts, const struct iovec iovec[], unsigned n_iovec, uint64_t *seqnum, Object **ret, uint64_t *offset) {
@@ -1088,6 +1296,10 @@ int journal_file_append_entry(JournalFile *f, const dual_timestamp *ts, const st
                 items[i].hash = o->data.hash;
         }
 
+        /* Order by the position on disk, in order to improve seek
+         * times for rotating media. */
+        qsort(items, n_iovec, sizeof(EntryItem), entry_item_cmp);
+
         r = journal_file_append_entry_internal(f, ts, xor_hash, items, n_iovec, seqnum, ret, offset);
 
         journal_file_post_change(f);
@@ -1872,6 +2084,10 @@ void journal_file_dump(JournalFile *f) {
                         printf("Type: OBJECT_DATA\n");
                         break;
 
+                case OBJECT_FIELD:
+                        printf("Type: OBJECT_FIELD\n");
+                        break;
+
                 case OBJECT_ENTRY:
                         printf("Type: OBJECT_ENTRY seqnum=%llu monotonic=%llu realtime=%llu\n",
                                (unsigned long long) le64toh(o->entry.seqnum),
@@ -1896,6 +2112,10 @@ void journal_file_dump(JournalFile *f) {
                                (unsigned long long) le64toh(o->tag.seqnum),
                                (unsigned long long) le64toh(o->tag.epoch));
                         break;
+
+                default:
+                        printf("Type: unknown (%u)\n", o->object.type);
+                        break;
                 }
 
                 if (o->object.flags & OBJECT_COMPRESSED)
@@ -1955,7 +2175,7 @@ void journal_file_print_header(JournalFile *f) {
                (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)),
+               yes_no(journal_file_rotate_suggested(f, 0)),
                (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)),
@@ -2002,6 +2222,7 @@ int journal_file_open(
         bool newly_created = false;
 
         assert(fname);
+        assert(ret);
 
         if ((flags & O_ACCMODE) != O_RDONLY &&
             (flags & O_ACCMODE) != O_RDWR)
@@ -2024,7 +2245,9 @@ int journal_file_open(
 #ifdef HAVE_XZ
         f->compress = compress;
 #endif
+#ifdef HAVE_GCRYPT
         f->seal = seal;
+#endif
 
         if (mmap_cache)
                 f->mmap = mmap_cache_ref(mmap_cache);
@@ -2054,14 +2277,31 @@ int journal_file_open(
         }
 
         if (f->last_stat.st_size == 0 && f->writable) {
-                newly_created = true;
+#ifdef HAVE_XATTR
+                uint64_t crtime;
+
+                /* Let's attach the creation time to the journal file,
+                 * so that the vacuuming code knows the age of this
+                 * file even if the file might end up corrupted one
+                 * day... Ideally we'd just use the creation time many
+                 * file systems maintain for each file, but there is
+                 * currently no usable API to query this, hence let's
+                 * emulate this via extended attributes. If extended
+                 * attributes are not supported we'll just skip this,
+                 * and rely solely on mtime/atime/ctime of the file.*/
+
+                crtime = htole64((uint64_t) now(CLOCK_REALTIME));
+                fsetxattr(f->fd, "user.crtime_usec", &crtime, sizeof(crtime), XATTR_CREATE);
+#endif
 
 #ifdef HAVE_GCRYPT
                 /* Try to load the FSPRG state, and if we can't, then
                  * just don't do sealing */
-                r = journal_file_fss_load(f);
-                if (r < 0)
-                        f->seal = false;
+                if (f->seal) {
+                        r = journal_file_fss_load(f);
+                        if (r < 0)
+                                f->seal = false;
+                }
 #endif
 
                 r = journal_file_init_header(f, template);
@@ -2072,6 +2312,8 @@ int journal_file_open(
                         r = -errno;
                         goto fail;
                 }
+
+                newly_created = true;
         }
 
         if (f->last_stat.st_size < (off_t) HEADER_SIZE_MIN) {
@@ -2142,9 +2384,7 @@ int journal_file_open(
         if (r < 0)
                 goto fail;
 
-        if (ret)
-                *ret = f;
-
+        *ret = f;
         return 0;
 
 fail:
@@ -2181,8 +2421,8 @@ int journal_file_rotate(JournalFile **f, bool compress, bool seal) {
         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_entry_seqnum),
-                 (unsigned long long) le64toh((*f)->header->tail_entry_realtime));
+                 (unsigned long long) le64toh((*f)->header->head_entry_seqnum),
+                 (unsigned long long) le64toh((*f)->header->head_entry_realtime));
 
         r = rename(old_file->path, p);
         free(p);
@@ -2475,7 +2715,7 @@ int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot_id, u
         return 1;
 }
 
-bool journal_file_rotate_suggested(JournalFile *f) {
+bool journal_file_rotate_suggested(JournalFile *f, usec_t max_file_usec) {
         assert(f);
 
         /* If we gained new header fields we gained new features,
@@ -2513,5 +2753,15 @@ bool journal_file_rotate_suggested(JournalFile *f) {
                         return true;
                 }
 
+        if (max_file_usec > 0) {
+                usec_t t, h;
+
+                h = le64toh(f->header->head_entry_realtime);
+                t = now(CLOCK_REALTIME);
+
+                if (h > 0 && t > h + max_file_usec)
+                        return true;
+        }
+
         return false;
 }