wiretap: Register a systemd Journal Export Block

The block is lightweight and doesn't have any options so the create
function doesn't really do anything, but it needs to be registered
so that when systemd journal files are opened, the wtap_block_create()
call works and doesn't segfault. Fix #17875

1 files changed, 21 insertions, 0 deletions

diff --git a/wiretap/wtap_opttypes.c b/wiretap/wtap_opttypes.c
index dda5475003..86afcdc02e 100644
--- a/wiretap/wtap_opttypes.c
+++ b/wiretap/wtap_opttypes.c
@@ -1623,6 +1623,12 @@ static void pkt_create(wtap_block_t block)
     block->mandatory_data = NULL;
 }
 
+static void sjeb_create(wtap_block_t block)
+{
+    /* Ensure this is null, so when g_free is called on it, it simply returns */
+    block->mandatory_data = NULL;
+}
+
 static void cb_create(wtap_block_t block)
 {
     /* Ensure this is null, so when g_free is called on it, it simply returns */
@@ -1853,6 +1859,16 @@ void wtap_opttypes_initialize(void)
         WTAP_OPTTYPE_FLAG_MULTIPLE_ALLOWED
     };
 
+    static wtap_blocktype_t journal_block = {
+        WTAP_BLOCK_SYSTEMD_JOURNAL_EXPORT, /* block_type */
+        "SJEB",                         /* name */
+        "systemd Journal Export Block", /* description */
+        sjeb_create,                    /* create */
+        NULL,                           /* free_mand */
+        NULL,                           /* copy_mand */
+        NULL                            /* options */
+    };
+
     static wtap_blocktype_t cb_block = {
         WTAP_BLOCK_CUSTOM,            /* block_type */
         "CB",                         /* name */
@@ -1924,6 +1940,11 @@ void wtap_opttypes_initialize(void)
     wtap_opttype_option_register(&pkt_block, OPT_PKT_VERDICT, &pkt_verdict);
 
     /*
+     * Register the SJEB and the (no) options that can appear in it.
+     */
+    wtap_opttype_block_register(&journal_block);
+
+    /*
      * Register the CB and the options that can appear in it.
      */
     wtap_opttype_block_register(&cb_block);