wasm bindings: enforce pointer length

* bindgen.py: print an error when a pointer argument doesn't have an annotated length
* ensure all bindings with pointers have length annotations
* add a couple helper functions for dealing with length annotations

scripts/bindgen.py

@@ -11,6 +11,11 @@ def needs_arg_ptr_stub(decl):
 			res = True
 	return(res)
 
+def printError(str):
+	# This prints a string with a red foreground color.
+	# See this link for an explanation of console escape codes: https://stackabuse.com/how-to-print-colored-text-in-python/
+	print("\x1b[38;5;196m" + "error: " + str + "\033[0;0m")
+
 
 def bindgen(apiName, spec, **kwargs):
 	guest_stubs_path = kwargs.get("guest_stubs")
@@ -152,8 +157,10 @@ def bindgen(apiName, spec, **kwargs):
 				argTag = arg['type']['tag']
 				argLen = arg.get('len')
 
-				if argTag == 'p' and argLen != None:
+				if argTag == 'p':
-
+					if argLen == None:
+						printError("binding '" + name + "' missing pointer length decoration for param '" + argName + "'")
+					else:
 						s += '\t{\n'
 						s += '\t\tOC_ASSERT(((char*)'+ argName + ' >= (char*)_mem) && (((char*)'+ argName +' - (char*)_mem) < m3_GetMemorySize(runtime)), "parameter \''+argName+'\' is out of bounds");\n'
 						s += '\t\tOC_ASSERT((char*)' + argName + ' + '

src/runtime.c

@@ -70,6 +70,25 @@ oc_str8 oc_runtime_get_wasm_memory()
     return (mem);
 }
 
+u64 orca_check_cstring(IM3Runtime runtime, const char* ptr)
+{
+    uint32_t memorySize = 0;
+    char* memory = (char*)m3_GetMemory(runtime, &memorySize, 0);
+
+    //NOTE: Here we are guaranteed that ptr is in [ memory ; memory + memorySize [
+    //      hence (memory + memorySize) - ptr is representable by size_t and <= memorySize
+    size_t maxLen = (memory + memorySize) - ptr;
+
+    u64 len = strnlen(ptr, maxLen);
+
+    if(len == maxLen)
+    {
+        //NOTE: string overflows wasm memory, return a length that will trigger the bounds check
+        len = maxLen + 1;
+    }
+    return (len + 1); //include null-terminator
+}
+
 void orca_wasm3_abort(IM3Runtime runtime, M3Result res, const char* file, const char* function, int line, const char* msg)
 {
     M3ErrorInfo errInfo = { 0 };
@@ -349,6 +368,7 @@ void oc_wasm_env_init(oc_wasm_env* runtime)
 #include "wasmbind/gles_api_bind_manual.c"
 #include "wasmbind/gles_api_bind_gen.c"
 #include "wasmbind/io_api_bind_gen.c"
+#include "wasmbind/surface_api_bind_manual.c"
 #include "wasmbind/surface_api_bind_gen.c"
 
 i32 orca_runloop(void* user)

src/wasmbind/core_api.json

@@ -8,17 +8,20 @@
 			  {"name": "fileLen",
 			   "type": {"name": "int", "tag": "i"}},
 			  {"name": "file",
-			   "type": {"name": "char*", "tag": "p"}},
+			   "type": {"name": "char*", "tag": "p"},
+				"len": {"count": "fileLen"}},
 			  {"name": "functionLen",
 			   "type": {"name": "int", "tag": "i"}},
 			  {"name": "function",
-			   "type": {"name": "char*", "tag": "p"}},
+			   "type": {"name": "char*", "tag": "p"},
+				"len": {"count": "functionLen"}},
 			  {"name": "line",
 			   "type": {"name": "int", "tag": "i"}},
 			  {"name": "msgLen",
 			   "type": {"name": "int", "tag": "i"}},
 			  {"name": "msg",
-			   "type": {"name": "char*", "tag": "p"}}
+			   "type": {"name": "char*", "tag": "p"},
+				"len": {"count": "msgLen"}}
 			]
 },
 {
@@ -33,15 +36,19 @@
 	"cname": "oc_assert_fail",
 	"ret": {"name": "void", "tag": "v"},
 	"args": [ {"name": "file",
-			   "type": {"name": "const char*", "tag": "p"}},
+			   "type": {"name": "const char*", "tag": "p"},
+				"len": {"proc": "orca_check_cstring", "args": ["file"]}},
 			  {"name": "function",
-			   "type": {"name": "const char*", "tag": "p"}},
+			   "type": {"name": "const char*", "tag": "p"},
+				"len": {"proc": "orca_check_cstring", "args": ["function"]}},
 			  {"name": "line",
 			   "type": {"name": "int", "tag": "i"}},
 			  {"name": "src",
-			   "type": {"name": "const char*", "tag": "p"}},
+			   "type": {"name": "const char*", "tag": "p"},
+				"len": {"proc": "orca_check_cstring", "args": ["src"]}},
 			  {"name": "note",
-			   "type": {"name": "const char*", "tag": "p"}}
+			   "type": {"name": "const char*", "tag": "p"},
+				"len": {"proc": "orca_check_cstring", "args": ["note"]}}
 			]
 },
 {
@@ -49,13 +56,16 @@
 	"cname": "oc_abort_ext",
 	"ret": {"name": "void", "tag": "v"},
 	"args": [ {"name": "file",
-			   "type": {"name": "const char*", "tag": "p"}},
+			   "type": {"name": "const char*", "tag": "p"},
+				"len": {"proc": "orca_check_cstring", "args": ["file"]}},
 			  {"name": "function",
-			   "type": {"name": "const char*", "tag": "p"}},
+			   "type": {"name": "const char*", "tag": "p"},
+				"len": {"proc": "orca_check_cstring", "args": ["function"]}},
 			  {"name": "line",
 			   "type": {"name": "int", "tag": "i"}},
 			  {"name": "note",
-			   "type": {"name": "const char*", "tag": "p"}}
+			   "type": {"name": "const char*", "tag": "p"},
+				"len": {"proc": "orca_check_cstring", "args": ["note"]}}
 			]
 },
 {

src/wasmbind/gles_api_bind_manual.c

@@ -3,25 +3,6 @@
 // Manual pointer size checking functions
 //------------------------------------------------------------------------
 
-u64 orca_gles_check_cstring(IM3Runtime runtime, const char* ptr)
-{
-    uint32_t memorySize = 0;
-    char* memory = (char*)m3_GetMemory(runtime, &memorySize, 0);
-
-    //NOTE: Here we are guaranteed that ptr is in [ memory ; memory + memorySize [
-    //      hence (memory + memorySize) - ptr is representable by size_t and <= memorySize
-    size_t maxLen = (memory + memorySize) - ptr;
-
-    u64 len = strnlen(ptr, maxLen);
-
-    if(len == maxLen)
-    {
-        //NOTE: string overflows wasm memory, return a length that will trigger the bounds check
-        len = maxLen + 1;
-    }
-    return (len + 1); //include null-terminator
-}
-
 u64 orca_gl_type_size(GLenum type)
 {
     u64 size = 8;
@@ -772,37 +753,37 @@ u64 orca_glGetUniformuiv_params_length(IM3Runtime runtime, GLuint program, GLint
 
 u64 orca_glGetFragDataLocation_name_length(IM3Runtime runtime, const GLchar* name)
 {
-    return (orca_gles_check_cstring(runtime, name));
+    return (orca_check_cstring(runtime, name));
 }
 
 u64 orca_glGetUniformBlockIndex_uniformBlockName_length(IM3Runtime runtime, const GLchar* uniformBlockName)
 {
-    return (orca_gles_check_cstring(runtime, uniformBlockName));
+    return (orca_check_cstring(runtime, uniformBlockName));
 }
 
 u64 orca_glGetProgramResourceIndex_name_length(IM3Runtime runtime, const GLchar* name)
 {
-    return (orca_gles_check_cstring(runtime, name));
+    return (orca_check_cstring(runtime, name));
 }
 
 u64 orca_glGetProgramResourceLocation_name_length(IM3Runtime runtime, const GLchar* name)
 {
-    return (orca_gles_check_cstring(runtime, name));
+    return (orca_check_cstring(runtime, name));
 }
 
 u64 orca_glBindAttribLocation_name_length(IM3Runtime runtime, const GLchar* name)
 {
-    return (orca_gles_check_cstring(runtime, name));
+    return (orca_check_cstring(runtime, name));
 }
 
 u64 orca_glGetAttribLocation_name_length(IM3Runtime runtime, const GLchar* name)
 {
-    return (orca_gles_check_cstring(runtime, name));
+    return (orca_check_cstring(runtime, name));
 }
 
 u64 orca_glGetUniformLocation_name_length(IM3Runtime runtime, const GLchar* name)
 {
-    return (orca_gles_check_cstring(runtime, name));
+    return (orca_check_cstring(runtime, name));
 }
 
 //------------------------------------------------------------------------
@@ -967,7 +948,7 @@ const void* glGetUniformIndices_stub(IM3Runtime runtime, IM3ImportContext _ctx,
         char* raw = ((char*)_mem + uniformNames[i]);
         OC_ASSERT(raw >= (char*)_mem && (raw - (char*)_mem) < memorySize, "uniformName[%i] is out of bounds", i);
 
-        u64 len = orca_gles_check_cstring(runtime, raw);
+        u64 len = orca_check_cstring(runtime, raw);
 
         OC_ASSERT(raw + len <= ((char*)_mem + memorySize), "uniformName[%i] overflows wasm memory", i);
 

src/wasmbind/io_api.json

@@ -4,7 +4,8 @@
 	"cname": "oc_bridge_io_single_rect",
 	"ret": {"name": "oc_io_cmp", "tag": "S"},
 	"args": [ {"name": "req",
-	           "type": {"name": "oc_io_req*", "tag": "p"}}]
+	           "type": {"name": "oc_io_req*", "tag": "p"},
+	       	   "len": {"components": 1}}]
 },
 {
     "name": "oc_file_open_with_request",
@@ -31,7 +32,8 @@
         {"name": "flags",
          "type": {"name": "oc_file_open_flags", "tag": "i"}},
         {"name": "desc",
-         "type": {"name": "oc_file_dialog_desc*", "cname": "oc_wasm_file_dialog_desc*", "tag": "p"}}
+         "type": {"name": "oc_file_dialog_desc*", "cname": "oc_wasm_file_dialog_desc*", "tag": "p"},
+     	 "len": {"components": 1}}
     ]
 }
 ]

src/wasmbind/surface_api.json

@@ -34,7 +34,8 @@
 		{"name": "region",
 		 "type": {"name": "oc_rect", "tag": "S"}},
 		{"name": "pixels",
-		 "type": {"name": "u8*", "tag": "p"}}]
+		 "type": {"name": "u8*", "tag": "p"},
+		 "len": {"proc": "orca_image_upload_region_rgba8_length", "args": ["region"]}}]
 },
 {
     "name": "oc_surface_get_size",
@@ -96,11 +97,13 @@
 		{"name": "primitiveCount",
 		 "type": {"name": "u32", "tag": "i"}},
 		{"name": "primitives",
-		 "type": {"name": "oc_primitive*", "tag": "p"}},
+		 "type": {"name": "oc_primitive*", "tag": "p"},
+		 "len": {"count": "primitiveCount"}},
 		{"name": "eltCount",
 		 "type": {"name": "u32", "tag": "i"}},
 		{"name": "elements",
-		 "type": {"name": "oc_path_elt*", "tag": "p"}}]
+		 "type": {"name": "oc_path_elt*", "tag": "p"},
+		 "len": {"count": "eltCount"}}]
 },
 {
 	"name": "oc_surface_canvas",

src/wasmbind/surface_api_bind_manual.c

@@ -0,0 +1,11 @@
+
+//------------------------------------------------------------------------
+// image length checks
+//------------------------------------------------------------------------
+
+u64 orca_image_upload_region_rgba8_length(IM3Runtime runtime, oc_rect rect)
+{
+    u64 pixelFormatWidth = sizeof(u8) * 4;
+    u64 len = rect.w * rect.h * pixelFormatWidth;
+    return len;
+}