Add system privilege PROFILE_ANY_ATTACHMENT and permission check.

Add some static_asserts.

Author: asfernandes

doc/sql.extensions/README.ddl.txt

@@ -557,6 +557,7 @@ GRANT_REVOKE_ANY_DDL_RIGHT		GRANT and REVOKE any DDL rights
 CREATE_PRIVILEGED_ROLES			Use SET SYSTEM PRIVILEGES in roles
 MODIFY_EXT_CONN_POOL			Manage properties of pool of external connections
 REPLICATE_INTO_DATABASE			Use replication API to load changesets into database
+PROFILE_ANY_ATTACHMENT			Profile other users' attachments
 
 
 22) New grantee type in GRANT and REVOKE operators - SYSTEM PRIVILEGE.

doc/sql.extensions/README.profiler.md

@@ -14,6 +14,8 @@ Remote profiling just forwards commands to the remote attachment. So it's possib
 
 Remote issued commands needs that the target attachment be in an idle state, i.e., not executing others requests. When they are not idle the call blocks waiting for that state.
 
+If remote attachment is from a different user, the calling user must have system privilege PROFILE_ANY_ATTACHMENT.
+
 After a session is started, PSQL and SQL statements statistics starts to be collected in memory. Note that a profile session collects data only of statements executed in the same attachment associated with the session.
 
 Data is aggregated and stored per requests (i.e. a statement execution). When querying snapshot tables, user may do extra aggregation per statements or use the auxiliary views that do that automatically.

src/jrd/ProfilerManager.cpp

@@ -88,6 +88,7 @@ namespace
 			event_t clientEvent;
 			USHORT bufferSize;
 			Tag tag;
+			char userName[USERNAME_LENGTH + 1];	// \0 if has PROFILE_ANY_ATTACHMENT
 			alignas(FB_ALIGNMENT) UCHAR buffer[4096];
 		};
 
@@ -107,12 +108,14 @@ namespace
 		template <typename Input, typename Output>
 		void sendAndReceive(thread_db* tdbb, Tag tag, const Input* in, Output* out)
 		{
+			static_assert(sizeof(*in) <= sizeof(std::declval<Header>().buffer), "Buffer size too small");
 			internalSendAndReceive(tdbb, tag, in, sizeof(*in), out, sizeof(*out));
 		}
 
 		template <typename Input>
 		void send(thread_db* tdbb, Tag tag, const Input* in)
 		{
+			static_assert(sizeof(*in) <= sizeof(std::declval<Header>().buffer), "Buffer size too small");
 			internalSendAndReceive(tdbb, tag, in, sizeof(*in), nullptr, 0);
 		}
 
@@ -757,6 +760,8 @@ void ProfilerIpc::mutexBug(int osErrorCode, const char* text)
 void ProfilerIpc::internalSendAndReceive(thread_db* tdbb, Tag tag,
 	const void* in, unsigned inSize, void* out, unsigned outSize)
 {
+	const auto attachment = tdbb->getAttachment();
+
 	{	// scope
 		ThreadStatusGuard tempStatus(tdbb);
 
@@ -782,9 +787,15 @@ void ProfilerIpc::internalSendAndReceive(thread_db* tdbb, Tag tag,
 
 	const auto header = sharedMemory->getHeader();
 
-	header->bufferSize = inSize;
 	header->tag = tag;
 
+	if (attachment->locksmith(tdbb, PROFILE_ANY_ATTACHMENT))
+		header->userName[0] = '\0';
+	else
+		strcpy(header->userName, attachment->getUserName().c_str());
+
+	header->bufferSize = inSize;
+
 	fb_assert(inSize <= sizeof(header->buffer));
 	memcpy(header->buffer, in, inSize);
 
@@ -928,6 +939,9 @@ void ProfilerListener::processCommand(thread_db* tdbb)
 	const auto header = ipc->sharedMemory->getHeader();
 	const auto profilerManager = attachment->getProfilerManager(tdbb);
 
+	if (header->userName[0] && attachment->getUserName() != header->userName)
+		status_exception::raise(Arg::Gds(isc_miss_prvlg) << "PROFILE_ANY_ATTACHMENT");
+
 	using Tag = ProfilerIpc::Tag;
 
 	switch (header->tag)
@@ -983,6 +997,7 @@ void ProfilerListener::processCommand(thread_db* tdbb)
 				in->pluginOptionsNull ? 0 : in->pluginOptions.length);
 
 			const auto out = reinterpret_cast<ProfilerPackage::StartSessionOutput::Type*>(header->buffer);
+			static_assert(sizeof(*out) <= sizeof(header->buffer), "Buffer size too small");
 			header->bufferSize = sizeof(*out);
 
 			out->sessionIdNull = FB_FALSE;

src/jrd/SystemPrivileges.h

@@ -65,6 +65,7 @@ SYSTEM_PRIVILEGE(CREATE_PRIVILEGED_ROLES)
 SYSTEM_PRIVILEGE(GET_DBCRYPT_INFO)
 SYSTEM_PRIVILEGE(MODIFY_EXT_CONN_POOL)
 SYSTEM_PRIVILEGE(REPLICATE_INTO_DATABASE)
+SYSTEM_PRIVILEGE(PROFILE_ANY_ATTACHMENT)
 
 #ifdef FB_JRD_SYSTEM_PRIVILEGES_TMP
 maxSystemPrivilege