[PATCH v5 16/21] migration: Add helpers to detect TLS capability

[Peter Xu <peterx@redhat.com>]

Add migrate_tls_enabled() to detect whether TLS is configured.

Add migrate_channel_requires_tls() to detect whether the specific channel
requires TLS.

No functional change intended.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 migration/channel.c   | 10 ++--------
 migration/migration.c |  8 ++++++++
 migration/migration.h |  2 ++
 migration/multifd.c   |  7 +------
 migration/tls.c       |  9 +++++++++
 migration/tls.h       |  4 ++++
 6 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/migration/channel.c b/migration/channel.c
index c6a8dcf1d7..36e59eaeec 100644
--- a/migration/channel.c
+++ b/migration/channel.c
@@ -38,10 +38,7 @@ void migration_channel_process_incoming(QIOChannel *ioc)
     trace_migration_set_incoming_channel(
         ioc, object_get_typename(OBJECT(ioc)));
 
-    if (s->parameters.tls_creds &&
-        *s->parameters.tls_creds &&
-        !object_dynamic_cast(OBJECT(ioc),
-                             TYPE_QIO_CHANNEL_TLS)) {
+    if (migrate_channel_requires_tls(ioc)) {
         migration_tls_channel_process_incoming(s, ioc, &local_err);
     } else {
         migration_ioc_register_yank(ioc);
@@ -71,10 +68,7 @@ void migration_channel_connect(MigrationState *s,
         ioc, object_get_typename(OBJECT(ioc)), hostname, error);
 
     if (!error) {
-        if (s->parameters.tls_creds &&
-            *s->parameters.tls_creds &&
-            !object_dynamic_cast(OBJECT(ioc),
-                                 TYPE_QIO_CHANNEL_TLS)) {
+        if (migrate_channel_requires_tls(ioc)) {
             migration_tls_channel_connect(s, ioc, hostname, &error);
 
             if (!error) {
diff --git a/migration/migration.c b/migration/migration.c
index cd9650f2e2..71a50b5c37 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -49,6 +49,7 @@
 #include "trace.h"
 #include "exec/target_page.h"
 #include "io/channel-buffer.h"
+#include "io/channel-tls.h"
 #include "migration/colo.h"
 #include "hw/boards.h"
 #include "hw/qdev-properties.h"
@@ -4250,6 +4251,13 @@ void migration_global_dump(Monitor *mon)
                    ms->clear_bitmap_shift);
 }
 
+bool migrate_tls_enabled(void)
+{
+    MigrationState *s = migrate_get_current();
+
+    return s->parameters.tls_creds && *s->parameters.tls_creds;
+}
+
 #define DEFINE_PROP_MIG_CAP(name, x)             \
     DEFINE_PROP_BOOL(name, MigrationState, enabled_capabilities[x], false)
 
diff --git a/migration/migration.h b/migration/migration.h
index 6ee520642f..db176ea749 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -436,6 +436,8 @@ bool migrate_use_events(void);
 bool migrate_postcopy_blocktime(void);
 bool migrate_background_snapshot(void);
 bool migrate_postcopy_preempt(void);
+/* Whether TLS is enabled for migration? */
+bool migrate_tls_enabled(void);
 
 /* Sending on the return path - generic and then for each message type */
 void migrate_send_rp_shut(MigrationIncomingState *mis,
diff --git a/migration/multifd.c b/migration/multifd.c
index 9ea4f581e2..19e3c44491 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -782,17 +782,12 @@ static bool multifd_channel_connect(MultiFDSendParams *p,
                                     QIOChannel *ioc,
                                     Error *error)
 {
-    MigrationState *s = migrate_get_current();
-
     trace_multifd_set_outgoing_channel(
         ioc, object_get_typename(OBJECT(ioc)),
         migrate_get_current()->hostname, error);
 
     if (!error) {
-        if (s->parameters.tls_creds &&
-            *s->parameters.tls_creds &&
-            !object_dynamic_cast(OBJECT(ioc),
-                                 TYPE_QIO_CHANNEL_TLS)) {
+        if (migrate_channel_requires_tls(ioc)) {
             multifd_tls_channel_connect(p, ioc, &error);
             if (!error) {
                 /*
diff --git a/migration/tls.c b/migration/tls.c
index 32c384a8b6..bd1fa01048 100644
--- a/migration/tls.c
+++ b/migration/tls.c
@@ -166,3 +166,12 @@ void migration_tls_channel_connect(MigrationState *s,
                               NULL,
                               NULL);
 }
+
+bool migrate_channel_requires_tls(QIOChannel *ioc)
+{
+    if (!migrate_tls_enabled()) {
+        return false;
+    }
+
+    return !object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_TLS);
+}
diff --git a/migration/tls.h b/migration/tls.h
index de4fe2cafd..a54c1dcec7 100644
--- a/migration/tls.h
+++ b/migration/tls.h
@@ -37,4 +37,8 @@ void migration_tls_channel_connect(MigrationState *s,
                                    QIOChannel *ioc,
                                    const char *hostname,
                                    Error **errp);
+
+/* Whether the QIO channel requires further TLS handshake? */
+bool migrate_channel_requires_tls(QIOChannel *ioc);
+
 #endif
-- 
2.32.0