x86_64: adapt MiG generated stubs to use mach_port_name_inlined_t for inlined port rights.

For i686, we just change the code to use mach_port_name_inlined_t when
defining the types. This is a no-op.

For x86_64, there's a few things that are different:
- In the server code, the server handler can get inlined ports and the
  array will be resized and cast as an array of mach_port_name_t. Output
  parameters have a similar treatment where the inlined array in the
  output is used as an array of mach_port_name_t but resized to look like
  a mach_port_name_inlined_t.
- In the user side, we follow the same approach. Input ports as arrays
  of mach_port_name_t are expanded into an array of mach_port_name_inlined_t.
  Output ports are then converted back into an array of
  mach_port_name_inlined_t so that they fit into the expected message
  format.

Essentially, regardless of whether port rights are inline or out of
line, user interfaces and server stubs always receive an array of port
rights, not mach_port_name_inlined_t. However, inlined port rights will
be exchanged using mach_port_name_inlined_t.
Message-ID: <20231124213041.952886-4-flaviocruz@gmail.com>

1 files changed, 119 insertions, 36 deletions

diff --git a/server.c b/server.c
index 00ca3f2..b95e4d0 100644
--- a/server.c
+++ b/server.c
@@ -455,10 +455,27 @@ WriteTypeCheck(FILE *file, const argument_t *arg)
 		    arg->argRequestPos, arg->argTTName,
 		    arg->argLongForm ? "l" : "",
 		    it->itNumber);
-	fprintf(file, "\t    (In%dP->%s.msgt%s_size != %d)))\n",
-		arg->argRequestPos, arg->argTTName,
-		arg->argLongForm ? "l" : "",
-		it->itSize);
+	if (IS_64BIT_ABI && it->itUserlandPort && arg->argLongForm) {
+	    /* 64 bit inlined ports are 8 bytes long but we use mach_port_name_t when passing them out of line. */
+	    fprintf(file, "\t    (In%dP->%s.msgtl_size != %d && In%dP->%s.msgtl_header.msgt_inline == TRUE) || \n",
+		    arg->argRequestPos,
+		    arg->argTTName,
+		    it->itSize,
+		    arg->argRequestPos,
+		    arg->argTTName);
+	    fprintf(file, "\t    (In%dP->%s.msgtl_size != %d && In%dP->%s.msgtl_header.msgt_inline == FALSE)",
+		    arg->argRequestPos,
+		    arg->argTTName,
+		    port_name_size_in_bits,
+		    arg->argRequestPos,
+		    arg->argTTName);
+	} else {
+	    fprintf(file, "\t    (In%dP->%s.msgt%s_size != %d)",
+		    arg->argRequestPos, arg->argTTName,
+		    arg->argLongForm ? "l" : "",
+		    it->itSize);
+	}
+	fprintf(file, "))\n");
     }
     WriteMsgError(file, "MIG_BAD_ARGUMENTS");
     fprintf(file, "#endif\t/* TypeCheck */\n");
@@ -565,6 +582,7 @@ static const char *
 InArgMsgField(const argument_t *arg)
 {
     static char buffer[100];
+    const ipc_type_t *it = arg->argType;
 
     /*
      *	Inside the kernel, the request and reply port fields
@@ -588,6 +606,9 @@ static void
 WriteExtractArgValue(FILE *file, const argument_t *arg)
 {
     const ipc_type_t *it = arg->argType;
+    const bool is_inlined_port = it->itUserlandPort && it->itInLine &&
+		akIdent(arg->argKind) != akeRequestPort && akIdent(arg->argKind) != akeReplyPort;
+    const char* arg_suffix = is_inlined_port ? ".name" : "";
     bool have_payload;
 
     if (arg->argMultiplier > 1)
@@ -618,17 +639,18 @@ WriteExtractArgValue(FILE *file, const argument_t *arg)
 		fprintf(file, "\t%s = %s;",
 			arg->argVarName, InArgMsgField(arg));
 	    else
-		WriteCopyType(file, it, "%s", "/* %s */ %s(%s)",
+		WriteCopyType(file, it, "%s", "/* %s */ %s(%s%s)",
 			      arg->argVarName, it->itInTrans,
-			      InArgMsgField(arg));
+			      InArgMsgField(arg), arg_suffix);
 	} else {
-	    WriteCopyType(file, it, "%s", "/* %s */ %s(%s)",
+	    WriteCopyType(file, it, "%s", "/* %s */ %s(%s%s)",
 			  arg->argVarName, it->itInTrans,
-			  InArgMsgField(arg));
+			  InArgMsgField(arg), arg_suffix);
 	}
-    } else
-	WriteCopyType(file, it, "%s", "/* %s */ %s",
-		      arg->argVarName, InArgMsgField(arg));
+    } else {
+	WriteCopyType(file, it, "%s", "/* %s */ %s%s",
+		      arg->argVarName, InArgMsgField(arg), arg_suffix);
+    }
     fprintf(file, "\n");
 }
 
@@ -745,12 +767,34 @@ WriteExtractArg(FILE *file, const argument_t *arg)
 
     if (akCheckAll(arg->argKind, akbReturnSnd|akbPointer))
 	WriteInitializePtr(file, arg);
+    if (akCheckAll(arg->argKind, akbSendRcv|akbPointer)) {
+	if (akCheck(arg->argKind, akbIndefinite)) {
+	    fprintf(file, "\tif (In%dP->%s%s.msgt_inline) {\n",
+		    arg->argRequestPos, arg->argTTName, arg->argLongForm ? ".msgtl_header" : "");
+	    fprintf(file, "\t\t%sP = (mach_port_t *)%s;\n", arg->argVarName, InArgMsgField(arg));
+	    fprintf(file, "\t\tmach_msg_type_number_t i;\n");
+	    fprintf(file, "\t\t/* Resizes the mach_port_name_inlined_t input array as an array of mach_port_name_t. */\n");
+	    fprintf(file, "\t\tfor (i = 1; i < In%dP->%s.msgt%s_number; i++) {\n",
+		    arg->argRequestPos, arg->argTTName, arg->argLongForm ? "l" : "");
+	    fprintf(file, "\t\t\t%sP[i] = %s[i].name;\n", arg->argVarName, InArgMsgField(arg));
+	    fprintf(file, "\t\t}\n");
+	    fprintf(file, "\t} else {\n");
+	    fprintf(file, "\t\t%sP = %s%s;\n", arg->argVarName, InArgMsgField(arg), OOLPostfix);
+	    fprintf(file, "\t}\n");
+	}
+	else
+	    assert(false);
+    }
 }
 
 static void
 WriteServerCallArg(FILE *file, const argument_t *arg)
 {
     const ipc_type_t *it = arg->argType;
+    const bool is_inlined_port = it->itUserlandPort &&
+		akIdent(arg->argKind) != akeRequestPort && akIdent(arg->argKind) != akeReplyPort && it->itInLine;
+    const char* arg_suffix = is_inlined_port ? ".name" : "";
+
     bool NeedClose = false;
 
     if (IsKernelServer) {
@@ -792,10 +836,10 @@ WriteServerCallArg(FILE *file, const argument_t *arg)
 		    OOLPostfix);
 	}
 	else
-	    fprintf(file, "%s", InArgMsgField(arg));
+	    fprintf(file, "%s%s", InArgMsgField(arg), arg_suffix);
     }
     else
-	fprintf(file, "OutP->%s", arg->argMsgField);
+	fprintf(file, "OutP->%s%s", arg->argMsgField, arg_suffix);
 
     if (NeedClose)
 	fprintf(file, ")");
@@ -818,7 +862,7 @@ WriteDestroyArg(FILE *file, const argument_t *arg)
 	 */
 	argument_t *count = arg->argCount;
 	ipc_type_t *btype = it->itElement;
-	int	multiplier = btype->itTypeSize / btype->itNumber;
+	int	multiplier = it->itUserlandPort ? port_name_size : btype->itTypeSize / btype->itNumber;
 
 	fprintf(file, "\tif (OutP->%s == KERN_SUCCESS)\n",
 		arg->argRoutine->rtRetCode->argMsgField);
@@ -938,6 +982,8 @@ static void
 WritePackArgValue(FILE *file, const argument_t *arg)
 {
     const ipc_type_t *it = arg->argType;
+    const bool is_inlined_port = it->itUserlandPort && it->itInLine;
+    const char* arg_suffix = is_inlined_port ? ".name" : "";
 
     fprintf(file, "\n");
 
@@ -965,6 +1011,7 @@ WritePackArgValue(FILE *file, const argument_t *arg)
 	else {
 	    argument_t *count = arg->argCount;
 	    ipc_type_t *btype = it->itElement;
+	    const bool is_64bit_port = IS_64BIT_ABI && btype->itUserlandPort;
 
 	    /* Note btype->itNumber == count->argMultiplier */
 
@@ -988,26 +1035,41 @@ WritePackArgValue(FILE *file, const argument_t *arg)
 			    arg->argTTName,
 			    arg->argLongForm ? ".msgtl_header" : "",
 			    arg->argDealloc->argVarName);
+		if (is_64bit_port) {
+		    /* We are passing the ports out of line, so they will always have the same size as a port name. */
+		    fprintf(file, "\t\tOutP->%s%s.msgt_size = %d;\n",
+			    arg->argTTName,
+			    arg->argLongForm ? ".msgtl_header" : "",
+			    port_name_size_in_bits);
+		}
 		fprintf(file, "\t\tOutP->%s%s = %sP;\n",
-			arg->argMsgField,
-			OOLPostfix,
-			arg->argVarName);
+		    arg->argMsgField,
+		    OOLPostfix,
+		    arg->argVarName);
 		if (!arg->argRoutine->rtSimpleFixedReply)
 		    fprintf(file, "\t\tmsgh_simple = FALSE;\n");
-		fprintf(file, "\t}\n\telse {\n\t");
+		fprintf(file, "\t}\n\telse {\n");
+	    }
+	    fprintf(file, "\t\tif (%s) {\n", count->argVarName);
+	    if (it->itIndefinite) {
+		if (is_64bit_port) {
+		    fprintf(file, "\t\t\t/* Copy array of mach_port_name_t into mach_port_name_inlined_t. */\n");
+		    fprintf(file, "\t\t\tmach_msg_type_number_t i;\n");
+		    fprintf(file, "\t\t\tfor(i = 0; i < %s; i++) {\n", count->argVarName);
+		    fprintf(file, "\t\t\t\t/* Clear the whole message with zeros. */\n");
+		    fprintf(file, "\t\t\t\tOutP->%s[i].kernel_port_do_not_use = 0;\n", arg->argMsgField);
+		    fprintf(file, "\t\t\t\tOutP->%s[i].name = %s[i];\n", arg->argMsgField, arg->argVarName);
+		    fprintf(file, "\t\t\t}\n");
+		} else {
+		    fprintf(file, "\t\t\tmemcpy(OutP->%s, %s, ",
+				arg->argMsgField, arg->argVarName);
+		    if (btype->itTypeSize > 1)
+			fprintf(file, "%d * ", btype->itTypeSize);
+		    fprintf(file, "%s);\n", count->argVarName);
+		}
 	    }
-	    fprintf(file, "\tif (%s)\n", count->argVarName);
-	    if (it->itIndefinite)
-		fprintf(file, "\t");
-	    fprintf(file, "\t\tmemcpy(OutP->%s, %s, ",
-		    arg->argMsgField, arg->argVarName);
-	    if (btype->itTypeSize > 1)
-		fprintf(file, "%d * ",
-			btype->itTypeSize);
-	    fprintf(file, "%s);\n",
-		count->argVarName);
-	    if (it->itIndefinite)
-		fprintf(file, "\t}\n");
+	    fprintf(file, "\t\t}\n");
+	    fprintf(file, "\t}\n");
 	}
     }
     else if (arg->argMultiplier > 1)
@@ -1015,12 +1077,12 @@ WritePackArgValue(FILE *file, const argument_t *arg)
 		      arg->argMsgField,
 		      arg->argMultiplier,
 		      arg->argVarName);
-    else if (it->itOutTrans != strNULL)
-	WriteCopyType(file, it, "OutP->%s", "/* %s */ %s(%s)",
-		      arg->argMsgField, it->itOutTrans, arg->argVarName);
-    else
-	WriteCopyType(file, it, "OutP->%s", "/* %s */ %s",
-		      arg->argMsgField, arg->argVarName);
+    else if (it->itOutTrans != strNULL) {
+	WriteCopyType(file, it, "OutP->%s%s", "/* %s%s */ %s(%s)",
+		      arg->argMsgField, arg_suffix, it->itOutTrans, arg->argVarName);
+    } else
+	WriteCopyType(file, it, "OutP->%s%s", "/* %s%s */ %s",
+		      arg->argMsgField, arg_suffix, arg->argVarName);
 }
 
 static void
@@ -1198,6 +1260,8 @@ WritePackArg(FILE *file, const argument_t *arg)
 	    fprintf(file, "\tOutP->%s = strlen(OutP->%s) + 1;\n",
 		    arg->argCount->argMsgField, arg->argMsgField);
 	} else if (it->itIndefinite) {
+	    const bool is_64bit_port = IS_64BIT_ABI && it->itUserlandPort;
+
 	    /*
 	     * We know that array is in reply message.
 	     */
@@ -1216,12 +1280,31 @@ WritePackArg(FILE *file, const argument_t *arg)
 			arg->argTTName,
 			arg->argLongForm ? ".msgtl_header" : "",
 			arg->argDealloc->argVarName);
+	    if (is_64bit_port) {
+		/* We are passing the ports out of line, so they will always have the same size as a port name. */
+		fprintf(file, "\t\tOutP->%s%s.msgt_size = %d;\n",
+			arg->argTTName,
+			arg->argLongForm ? ".msgtl_header" : "",
+			port_name_size_in_bits);
+	    }
 	    fprintf(file, "\t\tOutP->%s%s = %sP;\n",
 			arg->argMsgField,
 			OOLPostfix,
 			arg->argVarName);
 	    if (!arg->argRoutine->rtSimpleFixedReply)
 		fprintf(file, "\t\tmsgh_simple = FALSE;\n");
+	    if (is_64bit_port) {
+		fprintf(file, "\t} else {\n");
+		fprintf(file, "\t\t/* Resize mach_port_name_t array into mach_port_name_inlined_t. */\n");
+		fprintf(file, "\t\t/* Work in reverse order to avoid overriding subsequent entries. */\n");
+		fprintf(file, "\t\tmach_msg_type_number_t i;\n");
+		fprintf(file, "\t\tfor(i = %s; i > 0; i--) {\n", arg->argCount->argVarName);
+		fprintf(file, "\t\t\tmach_port_name_t tmp_port_name = %sP[i - 1];\n", arg->argVarName);
+		fprintf(file, "\t\t\t/* Clear the whole message with zeros. */\n");
+		fprintf(file, "\t\t\tOutP->%s[i - 1].kernel_port_do_not_use = 0;\n", arg->argMsgField);
+		fprintf(file, "\t\t\tOutP->%s[i - 1].name = tmp_port_name;\n", arg->argMsgField, arg->argVarName);
+		fprintf(file, "\t\t}\n");
+	    }
 	    fprintf(file, "\t}\n");
 	}
     }