shared/bus-unit-util: add helper for ImportCredentialEx= and fix naming confusion

We add D-Bus properties like "*Ex" because we cannot change the D-Bus property
type without breaking backward comapatibility. But those names are only for
D-Bus, not for config file stanzas or the command-line parser. There, we can
change the type, or in other words, there is no type, just a free-form string
whose interpretation we can extend or change. Commit
831f208783aeac443e6f2fc2efc3119535a032ef that added ProtectHostnameEx was
confused, because it added ImportCredentialEx in places where parsing of
ImportCredential should be have been extended.

On D-Bus, we send ImportCrednential in preference, and ImportCredentialEx only
when required. This way we send less bytes on the wire and support older
systems that don't understand the new property.

Partially resolves https://github.com/systemd/systemd/issues/37174.

diff --git a/src/shared/bus-unit-util.c b/src/shared/bus-unit-util.c
index cda870cc0fd69de047ea631a9cecc5c2278b7ba6..aa61ab8dbc8ed389fd20044f68da24961e2a16cd 100644 (file)
--- a/src/shared/bus-unit-util.c
+++ b/src/shared/bus-unit-util.c
@@ -1113,6 +1113,56 @@ static int bus_append_load_credential(sd_bus_message *m, const char *field, cons
         return 1;
 }
 
+static int bus_append_import_credential(sd_bus_message *m, const char *field, const char *eq) {
+        int r;
+
+        if (isempty(eq))
+                r = sd_bus_message_append(m, "(sv)", "ImportCredential", "as", 0);
+        else {
+                _cleanup_free_ char *word = NULL;
+                const char *p = eq;
+
+                r = extract_first_word(&p, &word, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+                if (r == -ENOMEM)
+                        return log_oom();
+                if (r < 0)
+                        return log_error_errno(r, "Failed to parse %s= parameter: %s", field, eq);
+                if (r == 0)
+                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Missing argument to %s=.", field);
+
+                if (!p)
+                        r = sd_bus_message_append(m, "(sv)", "ImportCredential", "as", 1, eq);
+                else {
+                        /* We need to send ImportCredentialEx */
+                        r = sd_bus_message_open_container(m, 'r', "sv");
+                        if (r < 0)
+                                return bus_log_create_error(r);
+
+                        r = sd_bus_message_append_basic(m, 's', "ImportCredentialEx");
+                        if (r < 0)
+                                return bus_log_create_error(r);
+
+                        r = sd_bus_message_open_container(m, 'v', "a(ss)");
+                        if (r < 0)
+                                return bus_log_create_error(r);
+
+                        r = sd_bus_message_append(m, "a(ss)", 1, word, p);
+                        if (r < 0)
+                                return bus_log_create_error(r);
+
+                        r = sd_bus_message_close_container(m);
+                        if (r < 0)
+                                return bus_log_create_error(r);
+
+                        r = sd_bus_message_close_container(m);
+                }
+        }
+        if (r < 0)
+                return bus_log_create_error(r);
+
+        return 1;
+}
+
 static int bus_append_cgroup_property(sd_bus_message *m, const char *field, const char *eq) {
         if (STR_IN_SET(field, "DevicePolicy",
                               "Slice",
@@ -1389,59 +1439,8 @@ static int bus_append_execute_property(sd_bus_message *m, const char *field, con
         if (STR_IN_SET(field, "LoadCredential", "LoadCredentialEncrypted"))
                 return bus_append_load_credential(m, field, eq);
 
-        if (streq(field, "ImportCredential")) {
-                if (isempty(eq))
-                        r = sd_bus_message_append(m, "(sv)", field, "as", 0);
-                else
-                        r = sd_bus_message_append(m, "(sv)", field, "as", 1, eq);
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                return 1;
-        }
-
-        if (streq(field, "ImportCredentialEx")) {
-                r = sd_bus_message_open_container(m, 'r', "sv");
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                r = sd_bus_message_append_basic(m, 's', field);
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                r = sd_bus_message_open_container(m, 'v', "a(ss)");
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                if (isempty(eq))
-                        r = sd_bus_message_append(m, "a(ss)", 0);
-                else {
-                         _cleanup_free_ char *word = NULL;
-                        const char *p = eq;
-
-                        r = extract_first_word(&p, &word, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
-                        if (r == -ENOMEM)
-                                return log_oom();
-                        if (r < 0)
-                                return log_error_errno(r, "Failed to parse %s= parameter: %s", field, eq);
-                        if (r == 0)
-                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Missing argument to %s=.", field);
-
-                        r = sd_bus_message_append(m, "a(ss)", 1, word, p);
-                }
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                r = sd_bus_message_close_container(m);
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                r = sd_bus_message_close_container(m);
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                return 1;
-        }
+        if (STR_IN_SET(field, "ImportCredential", "ImportCredentialEx"))
+                return bus_append_import_credential(m, field, eq);
 
         if (streq(field, "LogExtraFields")) {
                 r = sd_bus_message_open_container(m, 'r', "sv");