journal: include tag object header in hmac

This commit is contained in:
Lennart Poettering 2012-08-13 21:52:58 +02:00
parent b0af6f41ea
commit d98cc1f29f
2 changed files with 30 additions and 8 deletions

View File

@ -124,6 +124,7 @@ _packed_ struct EntryArrayObject {
_packed_ struct TagObject {
ObjectHeader object;
uint64_t seqnum;
uint8_t tag[TAG_LENGTH]; /* SHA-256 HMAC */
};
@ -182,6 +183,8 @@ _packed_ struct Header {
/* Added in 187 */
le64_t n_data;
le64_t n_fields;
/* Added in 189 */
le64_t n_tags;
};
#define FSPRG_HEADER_SIGNATURE ((char[]) { 'K', 'S', 'H', 'H', 'R', 'H', 'L', 'P' })

View File

@ -475,7 +475,7 @@ 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);
@ -1050,7 +1050,7 @@ 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 +1905,17 @@ 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 +1937,14 @@ 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 +2090,8 @@ 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 +2107,9 @@ 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;
}
@ -2322,7 +2340,8 @@ 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;
}