SERVER-49858 Don't forward API params from drop/dropDatabase to config servers

There are two mongos commands in API Version 1 that forward their parameters to internal commands: "drop" forwards to "_configsvrDropCollection" and "dropDatabase" forwards to "_configsvrDropDatabase".
Users should be permitted to call the mongos commands with apiVersion: "1", apiStrict: true, but the internal commands aren't in Version 1 and they'll reject these parameters. So, strip the API version parameters when forwarding.

8 files changed, 88 insertions, 52 deletions

diff --git a/src/mongo/db/command_generic_argument.cpp b/src/mongo/db/command_generic_argument.cpp
index 86e6f6c0196..4f4c9f34816 100644
--- a/src/mongo/db/command_generic_argument.cpp
+++ b/src/mongo/db/command_generic_argument.cpp
@@ -44,6 +44,7 @@ namespace {
 struct SpecialArgRecord {
     StringData name;
     bool isGeneric;
+    bool isApiParameter;
     bool stripFromRequest;
     bool stripFromReply;
 };
@@ -54,42 +55,43 @@ struct SpecialArgRecord {
 // clang-format off
 static constexpr std::array<SpecialArgRecord, 34> specials{{
     //                                       /-isGeneric
-    //                                       |  /-stripFromRequest
-    //                                       |  |  /-stripFromReply
-    {"apiVersion"_sd,                        1, 0, 0},
-    {"apiStrict"_sd,                         1, 0, 0},
-    {"apiDeprecationErrors"_sd,              1, 0, 0},
-    {"$audit"_sd,                            1, 1, 0},
-    {"$client"_sd,                           1, 1, 0},
-    {"$configServerState"_sd,                1, 1, 1},
-    {"$db"_sd,                               1, 1, 0},
-    {"allowImplicitCollectionCreation"_sd,   1, 1, 0},
-    {"$oplogQueryData"_sd,                   1, 1, 1},
-    {"$queryOptions"_sd,                     1, 0, 0},
-    {"$readPreference"_sd,                   1, 1, 0},
-    {"$replData"_sd,                         1, 1, 1},
-    {"$clusterTime"_sd,                      1, 1, 1},
-    {"maxTimeMS"_sd,                         1, 0, 0},
-    {"readConcern"_sd,                       1, 0, 0},
-    {"databaseVersion"_sd,                   1, 1, 0},
-    {"shardVersion"_sd,                      1, 1, 0},
-    {"tracking_info"_sd,                     1, 1, 0},
-    {"writeConcern"_sd,                      1, 0, 0},
-    {"lsid"_sd,                              1, 0, 0},
-    {"clientOperationKey"_sd,                1, 0, 0},
-    {"txnNumber"_sd,                         1, 0, 0},
-    {"autocommit"_sd,                        1, 0, 0},
-    {"coordinator"_sd,                       1, 0, 0},
-    {"startTransaction"_sd,                  1, 0, 0},
-    {"stmtId"_sd,                            1, 0, 0},
-    {"$gleStats"_sd,                         0, 0, 1},
-    {"operationTime"_sd,                     0, 0, 1},
-    {"lastCommittedOpTime"_sd,               0, 0, 1},
-    {"readOnly"_sd,                          0, 0, 1},
-    {"comment"_sd,                           1, 0, 0},
-    {"maxTimeMSOpOnly"_sd,                   1, 0, 0},
-    {"$configTime"_sd,                       1, 1, 1},
-    {"$topologyTime"_sd,                     1, 1, 1}}};
+    //                                       |  /-isApiParameter
+    //                                       |  |  /-stripFromRequest
+    //                                       |  |  |  /-stripFromReply
+    {"apiVersion"_sd,                        1, 1, 0, 0},
+    {"apiStrict"_sd,                         1, 1, 0, 0},
+    {"apiDeprecationErrors"_sd,              1, 1, 0, 0},
+    {"$audit"_sd,                            1, 0, 1, 0},
+    {"$client"_sd,                           1, 0, 1, 0},
+    {"$configServerState"_sd,                1, 0, 1, 1},
+    {"$db"_sd,                               1, 0, 1, 0},
+    {"allowImplicitCollectionCreation"_sd,   1, 0, 1, 0},
+    {"$oplogQueryData"_sd,                   1, 0, 1, 1},
+    {"$queryOptions"_sd,                     1, 0, 0, 0},
+    {"$readPreference"_sd,                   1, 0, 1, 0},
+    {"$replData"_sd,                         1, 0, 1, 1},
+    {"$clusterTime"_sd,                      1, 0, 1, 1},
+    {"maxTimeMS"_sd,                         1, 0, 0, 0},
+    {"readConcern"_sd,                       1, 0, 0, 0},
+    {"databaseVersion"_sd,                   1, 0, 1, 0},
+    {"shardVersion"_sd,                      1, 0, 1, 0},
+    {"tracking_info"_sd,                     1, 0, 1, 0},
+    {"writeConcern"_sd,                      1, 0, 0, 0},
+    {"lsid"_sd,                              1, 0, 0, 0},
+    {"clientOperationKey"_sd,                1, 0, 0, 0},
+    {"txnNumber"_sd,                         1, 0, 0, 0},
+    {"autocommit"_sd,                        1, 0, 0, 0},
+    {"coordinator"_sd,                       1, 0, 0, 0},
+    {"startTransaction"_sd,                  1, 0, 0, 0},
+    {"stmtId"_sd,                            1, 0, 0, 0},
+    {"$gleStats"_sd,                         0, 0, 0, 1},
+    {"operationTime"_sd,                     0, 0, 0, 1},
+    {"lastCommittedOpTime"_sd,               0, 0, 0, 1},
+    {"readOnly"_sd,                          0, 0, 0, 1},
+    {"comment"_sd,                           1, 0, 0, 0},
+    {"maxTimeMSOpOnly"_sd,                   1, 0, 0, 0},
+    {"$configTime"_sd,                       1, 0, 1, 1},
+    {"$topologyTime"_sd,                     1, 0, 1, 1}}};
 // clang-format on
 
 template <bool SpecialArgRecord::*pmo>
@@ -112,6 +114,10 @@ bool isGenericArgument(StringData arg) {
     return filteredSpecialsContains<&SpecialArgRecord::isGeneric>(arg);
 }
 
+bool isApiParameter(StringData arg) {
+    return filteredSpecialsContains<&SpecialArgRecord::isApiParameter>(arg);
+}
+
 bool isRequestStripArgument(StringData arg) {
     return filteredSpecialsContains<&SpecialArgRecord::stripFromRequest>(arg);
 }
diff --git a/src/mongo/db/command_generic_argument.h b/src/mongo/db/command_generic_argument.h
index 69d695250ec..7f66a101137 100644
--- a/src/mongo/db/command_generic_argument.h
+++ b/src/mongo/db/command_generic_argument.h
@@ -41,6 +41,11 @@ namespace mongo {
 bool isGenericArgument(StringData arg);
 
 /**
+ * Returns true if the provided argument is related to the MongoDB Versioned API.
+ */
+bool isApiParameter(StringData arg);
+
+/**
  * Returns true if arg must be stripped from requests that are forwarded to shards.
  * Only generic arguments are stripped, and some of them are not.
  * See 'CommandHelpers::filterCommandRequestForPassthrough'.
diff --git a/src/mongo/db/commands.cpp b/src/mongo/db/commands.cpp
index 579603598e7..7fcbd220b6d 100644
--- a/src/mongo/db/commands.cpp
+++ b/src/mongo/db/commands.cpp
@@ -358,18 +358,45 @@ void CommandHelpers::appendCommandWCStatus(BSONObjBuilder& result,
     }
 }
 
-BSONObj CommandHelpers::appendPassthroughFields(const BSONObj& cmdObjWithPassthroughFields,
-                                                const BSONObj& request) {
+namespace {
+
+enum class FilterApiParameters { kPreserveApiParameters, kRemoveApiParameters };
+
+BSONObj _appendPassthroughFields(const BSONObj& cmdObjWithPassthroughFields,
+                                 const BSONObj& request,
+                                 FilterApiParameters filterApiParameters) {
     BSONObjBuilder b;
     b.appendElements(request);
-    for (const auto& elem : filterCommandRequestForPassthrough(cmdObjWithPassthroughFields)) {
+    for (const auto& elem :
+         CommandHelpers::filterCommandRequestForPassthrough(cmdObjWithPassthroughFields)) {
         const auto name = elem.fieldNameStringData();
-        if (isGenericArgument(name) && !request.hasField(name)) {
-            b.append(elem);
+        if (request.hasField(name)) {
+            continue;
+        }
+        if (filterApiParameters == FilterApiParameters::kRemoveApiParameters &&
+            isApiParameter(name)) {
+            continue;
         }
+        if (!isGenericArgument(name)) {
+            continue;
+        }
+        b.append(elem);
     }
     return b.obj();
 }
+}  // namespace
+
+BSONObj CommandHelpers::appendPassthroughFields(const BSONObj& cmdObjWithPassthroughFields,
+                                                const BSONObj& request) {
+    return _appendPassthroughFields(
+        cmdObjWithPassthroughFields, request, FilterApiParameters::kPreserveApiParameters);
+}
+
+BSONObj CommandHelpers::appendInternalPassthroughFields(const BSONObj& cmdObjWithPassthroughFields,
+                                                        const BSONObj& request) {
+    return _appendPassthroughFields(
+        cmdObjWithPassthroughFields, request, FilterApiParameters::kRemoveApiParameters);
+}
 
 BSONObj CommandHelpers::appendMajorityWriteConcern(const BSONObj& cmdObj,
                                                    WriteConcernOptions defaultWC) {
diff --git a/src/mongo/db/commands.h b/src/mongo/db/commands.h
index 590be041081..91e3c4b80f0 100644
--- a/src/mongo/db/commands.h
+++ b/src/mongo/db/commands.h
@@ -178,6 +178,12 @@ struct CommandHelpers {
                                            const BSONObj& request);
 
     /**
+     * Appends passthrough fields from a cmdObj to a given *internal* command request.
+     */
+    static BSONObj appendInternalPassthroughFields(const BSONObj& cmdObjWithPassthroughFields,
+                                                   const BSONObj& request);
+
+    /**
      * Returns a copy of 'cmdObj' with a majority writeConcern appended.  If the command object does
      * not contain a writeConcern, 'defaultWC' will be used instead, if supplied.
      */
diff --git a/src/mongo/db/s/config/configsvr_drop_collection_command.cpp b/src/mongo/db/s/config/configsvr_drop_collection_command.cpp
index fc74fafc0c5..77cf249fd41 100644
--- a/src/mongo/db/s/config/configsvr_drop_collection_command.cpp
+++ b/src/mongo/db/s/config/configsvr_drop_collection_command.cpp
@@ -59,10 +59,6 @@ class ConfigSvrDropCollectionCommand : public BasicCommand {
 public:
     ConfigSvrDropCollectionCommand() : BasicCommand("_configsvrDropCollection") {}
 
-    const std::set<std::string>& apiVersions() const {
-        return kApiVersions1;
-    }
-
     AllowedOnSecondary secondaryAllowed(ServiceContext*) const override {
         return AllowedOnSecondary::kNever;
     }
diff --git a/src/mongo/db/s/config/configsvr_drop_database_command.cpp b/src/mongo/db/s/config/configsvr_drop_database_command.cpp
index eb3ef547e70..56aa8db1d94 100644
--- a/src/mongo/db/s/config/configsvr_drop_database_command.cpp
+++ b/src/mongo/db/s/config/configsvr_drop_database_command.cpp
@@ -54,10 +54,6 @@ class ConfigSvrDropDatabaseCommand : public BasicCommand {
 public:
     ConfigSvrDropDatabaseCommand() : BasicCommand("_configsvrDropDatabase") {}
 
-    const std::set<std::string>& apiVersions() const {
-        return kApiVersions1;
-    }
-
     AllowedOnSecondary secondaryAllowed(ServiceContext*) const override {
         return AllowedOnSecondary::kNever;
     }
diff --git a/src/mongo/s/commands/cluster_drop_cmd.cpp b/src/mongo/s/commands/cluster_drop_cmd.cpp
index a69e3292597..608c5504ecd 100644
--- a/src/mongo/s/commands/cluster_drop_cmd.cpp
+++ b/src/mongo/s/commands/cluster_drop_cmd.cpp
@@ -96,7 +96,7 @@ public:
             ReadPreferenceSetting(ReadPreference::PrimaryOnly),
             "admin",
             CommandHelpers::appendMajorityWriteConcern(
-                CommandHelpers::appendPassthroughFields(
+                CommandHelpers::appendInternalPassthroughFields(
                     cmdObj, BSON("_configsvrDropCollection" << nss.toString())),
                 opCtx->getWriteConcern()),
             Shard::RetryPolicy::kIdempotent));
diff --git a/src/mongo/s/commands/cluster_drop_database_cmd.cpp b/src/mongo/s/commands/cluster_drop_database_cmd.cpp
index a78cb00fd79..dc04c7f21c3 100644
--- a/src/mongo/s/commands/cluster_drop_database_cmd.cpp
+++ b/src/mongo/s/commands/cluster_drop_database_cmd.cpp
@@ -97,8 +97,8 @@ public:
             ReadPreferenceSetting(ReadPreference::PrimaryOnly),
             "admin",
             CommandHelpers::appendMajorityWriteConcern(
-                CommandHelpers::appendPassthroughFields(cmdObj,
-                                                        BSON("_configsvrDropDatabase" << dbname)),
+                CommandHelpers::appendInternalPassthroughFields(
+                    cmdObj, BSON("_configsvrDropDatabase" << dbname)),
                 opCtx->getWriteConcern()),
             Shard::RetryPolicy::kIdempotent));