From 7b5fd91c543fe2d62d9decfa1737f8e17c0976b2 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Fri, 17 Aug 2012 03:00:09 +0200
Subject: [PATCH] journal: ensure that entries and tags are properly ordered

---
 src/journal/journal-verify.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/src/journal/journal-verify.c b/src/journal/journal-verify.c
index cfd6d4093..8b71d03c3 100644
--- a/src/journal/journal-verify.c
+++ b/src/journal/journal-verify.c
@@ -646,7 +646,7 @@ static int journal_file_parse_verification_key(JournalFile *f, const char *key)
         f->fsprg_seed = seed;
         f->fsprg_seed_size = seed_size;
 
-        f->fss_start_usec = start;
+        f->fss_start_usec = start * interval;
         f->fss_interval_usec = interval;
 
         return 0;
@@ -655,7 +655,7 @@ static int journal_file_parse_verification_key(JournalFile *f, const char *key)
 int journal_file_verify(JournalFile *f, const char *key) {
         int r;
         Object *o;
-        uint64_t p = 0, last_tag = 0, last_epoch = 0;
+        uint64_t p = 0, last_tag = 0, last_epoch = 0, last_tag_realtime = 0;
         uint64_t 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;
@@ -753,6 +753,12 @@ int journal_file_verify(JournalFile *f, const char *key) {
                         if (r < 0)
                                 goto fail;
 
+                        if (last_tag_realtime > le64toh(o->entry.realtime)) {
+                                log_error("Older entry after newer tag at %llu", (unsigned long long) p);
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
                         if (!entry_seqnum_set &&
                             le64toh(o->entry.seqnum) != le64toh(f->header->head_entry_seqnum)) {
                                 log_error("Head entry sequence number incorrect");
@@ -870,6 +876,13 @@ int journal_file_verify(JournalFile *f, const char *key) {
                                 goto fail;
                         }
 
+                        last_tag_realtime = (o->tag.epoch + 1) * f->fss_interval_usec + f->fss_start_usec;
+                        if (entry_realtime_set && entry_realtime >= last_tag_realtime) {
+                                log_error("Tag/entry realtime timestamp out of synchronization at %llu", (unsigned long long) p);
+                                r = -EBADMSG;
+                                goto fail;
+                        }
+
                         /* OK, now we know the epoch. So let's now set
                          * it, and calculate the HMAC for everything
                          * since the last tag. */