Add validation for ExportSection

* Each export's name is required to be unique among all the exports'
names.
* Each export's index is required to be within the bounds of its
associated index space.

Also populate module index spaces in Module constructor.

Author: cjamthagen

TBInit.py

@@ -214,7 +214,28 @@ def GlobalSection(self):
         pass
 
     def ExportSection(self):
-        pass
+        section = self.module.export_section
+        name_list = {}
+        for entry in section.export_entries:
+            name = ''.join(chr(c) for c in entry.field_str)
+            if name in name_list:
+                return(False)
+            name_list[name]=None
+
+            index = entry.index
+            if entry.kind == External_Kind.FUNCTION:
+                if index >= len(self.module.function_index_space):
+                    return(False)
+            if entry.kind == External_Kind.TABLE:
+                if index >= len(self.module.table_index_space):
+                    return(False)
+            if entry.kind == External_Kind.MEMORY:
+                if index >= len(self.module.memory_index_space):
+                    return(False)
+            if entry.kind == External_Kind.GLOBAL:
+                if index >= len(self.module.global_index_space):
+                    return(False)
+        return(True)
 
     def StartSection(self):
         pass
@@ -237,7 +258,8 @@ def ValidateAll(self):
         self.TableSection()
         self.MemorySection()
         self.GlobalSection()
-        self.ExportSection()
+        if not self.ExportSection():
+            return(False)
         self.StartSection()
         self.ElementSection()
         self.CodeSection()

argparser.py

@@ -748,11 +748,11 @@ def ReadImportSection(self):
             temp_import_entry.kind = kind
 
             # function type
-            if kind == 0:
+            if kind == External_Kind.FUNCTION:
                 import_type, offset, dummy = Read(import_section[6], offset, 'varuint32')
                 temp_import_entry.type = import_type
             # table type
-            elif kind == 1:
+            elif kind == External_Kind.TABLE:
                 table_type = Table_Type()
                 table_type.elemet_type, offset, dummy = Read(import_section[6], offset, 'varint7')
                 rsz_limits = Resizable_Limits()
@@ -762,7 +762,7 @@ def ReadImportSection(self):
                     rsz_limits.maximum, offset, dummy = Read(import_section[6], offset, 'varuint32')
                 table_type.limit = rsz_limits
                 temp_import_entry.type = table_type
-            elif kind == 2:
+            elif kind == External_Kind.MEMORY:
                 memory_type = Memory_Type()
                 rsz_limits = Resizable_Limits()
                 rsz_limits.flags, offset, dummy = Read(import_section[6], offset, 'varuint1')
@@ -771,7 +771,7 @@ def ReadImportSection(self):
                     rsz_limits.maximum, offset, dummy = Read(import_section[6], offset, 'varuint32')
                 memory_type.limits = rsz_limits
                 temp_import_entry.type = memory_type
-            elif kind == 3:
+            elif kind == External_Kind.GLOBAL:
                 global_type = Global_Type()
                 global_type.content_type, offset, dummy = Read(import_section[6], offset, 'uint8')
                 global_type.mutability, offset, dummy = Read(import_section[6], offset, 'varuint1')
@@ -1061,7 +1061,6 @@ def ReadGlobalSection(self):
             temp_gl_var.global_type = temp_gl_type
             GS.global_variables.append(deepcopy(temp_gl_var))
 
-
             count -= 1
             loop = True
             init_expr = []

section_structs.py

@@ -227,6 +227,11 @@ class Module():
     def __init__(self, type_section, import_section, function_section,
                  table_section, memory_section, global_section, export_section,
                  start_section, element_section, code_section, data_section):
+        self.function_index_space = []
+        self.global_index_space = []
+        self.memory_index_space = []
+        self.table_index_space = []
+
         self.type_section = type_section
         self.import_section = import_section
         self.function_section = function_section
@@ -238,3 +243,18 @@ def __init__(self, type_section, import_section, function_section,
         self.element_section = element_section
         self.code_section = code_section
         self.data_section = data_section
+
+        for entry in self.import_section.import_entry:
+            print(entry)
+            if entry.kind == External_Kind.FUNCTION:
+                self.function_index_space.append(entry)
+            if entry.kind == External_Kind.TABLE:
+                self.table_index_space.append(entry)
+            if entry.kind == External_Kind.MEMORY:
+                self.memory_index_space.append(entry)
+            if entry.kind == External_Kind.GLOBAL:
+                self.global_index_space.append(entry)
+
+        for entry in self.function_section.type_section_index:
+            print(entry)
+            self.function_index_space.append(entry)