REP: add json output to chkx report patchcandidates

Moved all the json functionality into the LibrarySideEffect
class so that the json and txt output could share the same path.

Author: waskyo

chb/buffer/LibraryCallCallsites.py

@@ -40,10 +40,13 @@
     from chb.api.CallTarget import StubTarget
     from chb.api.FunctionStub import SOFunction
     from chb.app.Instruction import Instruction
+    from chb.app.AppAccess import AppAccess
+    from chb.app.Function import Function
     from chb.models.BTerm import BTerm, BTermArithmetic
     from chb.models.FunctionSummary import FunctionSummary
     from chb.models.FunctionPrecondition import (
         FunctionPrecondition, PreDerefWrite)
+    from chb.mips.MIPSInstruction import MIPSInstruction
 
 
 class LibraryCallSideeffect:
@@ -233,6 +236,68 @@ def lentype(self) -> str:
             else:
                 return lenterm
 
+    @property
+    def dstoffset(self) -> Optional[int]:
+        """Returns the stack offset for our destination buffer"""
+        if self.dstarg is None:
+            return None
+        return self.dstarg.stack_address_offset()
+
+    def find_spare_instruction(self,
+                               app: 'AppAccess',
+                               fn: 'Function',
+                              ) -> Optional[str]:
+        if app.is_mips:
+            block = fn.block(self.baddr)
+            found = None
+            for (addr, instr) in block.instructions.items():
+                instr = cast("MIPSInstruction", instr)
+                if instr.iaddr > self.instr.iaddr:
+                    break
+                if instr.is_load_instruction:
+                    if str(instr.operands[0]) == "t9":
+                        found = instr.iaddr
+            return found
+        return None
+
+    def to_json_result(self, app: 'AppAccess') -> JSONResult:
+        if self.dstarg is None:
+            chklogger.logger.warning(
+                "No expression found for destination argument: %s", self)
+            return JSONResult("librarycallsideeffect", {}, "fail",
+                              "No expression found for destination argument")
+        dstoffset = self.dstoffset
+        if dstoffset is None:
+            chklogger.logger.warning(
+                "No value found for destination stack offset : %s", self)
+            return JSONResult("librarycallsideeffect", {}, "fail",
+                              "No value found for destination stack offset")
+
+        fn = app.function(self.faddr)
+        stackframe = fn.stackframe
+        stackbuffer = stackframe.get_stack_buffer(dstoffset)
+        if stackbuffer is None:
+            chklogger.logger.warning(
+                "No stackbuffer found for %s at offset %s", self.instr, dstoffset)
+            return JSONResult("librarycallsideeffect", {}, "fail",
+                              "No stackbuffer found for %s at offset %s" %
+                              (self.instr, dstoffset))
+
+        buffersize = stackbuffer.size
+        spare = self.find_spare_instruction(app, fn)
+
+        content: Dict[str, Any] = {}
+        content["annotation"] = self.instr.annotation
+        content["faddr"] = self.faddr
+        content["iaddr"] = self.instr.iaddr
+        content["buffersize"] = buffersize
+        content["target-function"] = self.summary.name
+        content["stack-offset"] = dstoffset
+        content["length-argument"] = str(self.lenarg)
+        content["spare"] = spare
+
+        return JSONResult("librarycallsideeffect", content, "ok")
+
     def __str__(self) -> str:
         return self.instr.iaddr + ": " + str(self.instr.annotation)
 

chb/cmdline/reportcmds.py

@@ -991,6 +991,30 @@ def perc(v: float) -> str:
     exit(0)
 
 
+def write_json_result(xfilename: Optional[str],
+                      jresult: JSONResult,
+                      schema_name: str,
+                     ) -> None:
+    if jresult.is_ok:
+        okresult = JU.jsonok(schema_name, jresult.content)
+        if xfilename is not None:
+            filename = xfilename + ".json"
+            with open(filename, "w") as fp:
+                json.dump(okresult, fp, indent=2)
+            chklogger.logger.info("JSON output written to " + filename)
+        else:
+            print(json.dumps(okresult))
+    else:
+        failresult = JU.jsonfail(jresult.reason)
+        if xfilename is not None:
+            filename = xfilename + ".json"
+            with open(filename, "w") as fp:
+                json.dump(failresult, fp, indent=2)
+            chklogger.logger.warning(
+                "JSON failure output written to " + filename)
+        else:
+            print(json.dumps(failresult))
+
 def report_buffer_bounds(args: argparse.Namespace) -> NoReturn:
 
     # arguments
@@ -1024,49 +1048,27 @@ def report_buffer_bounds(args: argparse.Namespace) -> NoReturn:
                 if calltgt.is_so_target:
                     libcalls.add_library_callsite(faddr, baddr, instr)
 
-    def write_json_result(
-            xfilename: Optional[str], jresult: JSONResult) -> None:
-        if jresult.is_ok:
-            okresult = JU.jsonok("bufferboundsassessment", jresult.content)
-            if xfilename is not None:
-                filename = xfilename + ".json"
-                with open(filename, "w") as fp:
-                    json.dump(okresult, fp, indent=2)
-                chklogger.logger.info("JSON output written to " + filename)
-            else:
-                print(json.dumps(okresult))
-        else:
-            failresult = JU.jsonfail(jresult.reason)
-            if xfilename is not None:
-                filename = xfilename + ".json"
-                with open(filename, "w") as fp:
-                    json.dump(failresult, fp, indent=2)
-                chklogger.logger.warning(
-                    "JSON failure output written to " + filename)
-            else:
-                print(json.dumps(failresult))
-
     if xjson:
         content: Dict[str, Any] = {}
         xinfodata = xinfo.to_json_result()
         if xinfodata.is_ok:
             content["identification"] = xinfodata.content
         else:
-            write_json_result(xoutput, xinfodata)
+            write_json_result(xoutput, xinfodata, "bufferboundsassessment")
         analysisstats = app.result_metrics.to_json_result()
         if analysisstats.is_ok:
             content["analysis"] = analysisstats.content
         else:
-            write_json_result(xoutput, analysisstats)
+            write_json_result(xoutput, analysisstats, "bufferboundsassessment")
 
         libcallsresult = libcalls.to_json_result()
         if libcallsresult.is_ok:
             content["bounds"] = libcallsresult.content
         else:
-            write_json_result(xoutput, libcallsresult)
+            write_json_result(xoutput, libcallsresult,"bufferboundsassessment" )
 
         write_json_result(xoutput, JSONResult(
-            "libcboundsanalysis", content, "ok"))
+            "libcboundsanalysis", content, "ok"), "bufferboundsassessment")
 
     if not xverbose:
         exit(0)
@@ -1181,50 +1183,55 @@ def include_target(target: 'CallTarget') -> bool:
         return target.name in xtargets
 
     for (faddr, blocks) in app.call_instructions().items():
-        fn = app.function(faddr)
-
         for (baddr, instrs) in blocks.items():
             for instr in instrs:
                 n_calls += 1
                 calltgt = instr.call_target
                 if calltgt.is_so_target and include_target(calltgt):
                     libcalls.add_library_callsite(faddr, baddr, instr)
 
-    print("Number of calls: " + str(n_calls))
+    chklogger.logger.debug("Number of calls: %s", n_calls)
 
     patchcallsites = libcalls.patch_callsites()
 
+    content: Dict[str, Any] = {}
+    if xjson:
+        xinfodata = xinfo.to_json_result()
+        if xinfodata.is_ok:
+            content["identification"] = xinfodata.content
+        else:
+            write_json_result(xoutput, xinfodata, "patchcandidates")
+
+    patch_records = []
+
     for pc in sorted(patchcallsites, key=lambda pc:pc.faddr):
-        instr = pc.instr
-        dstarg = pc.dstarg
-        if dstarg is None:
-            chklogger.logger.warning(
-                "No expression found for destination argument: %s",
-                str(instr))
-            continue
-        dstoffset = dstarg.stack_address_offset()
-        fn = app.function(pc.faddr)
-        stackframe = fn.stackframe
-        stackbuffer = stackframe.get_stack_buffer(dstoffset)
-        if stackbuffer is None:
-            chklogger.logger.warning(
-                "No stackbuffer found for %s at offset %s",
-                str(instr), str(dstoffset))
+        jresult = pc.to_json_result(app)
+        if not jresult.is_ok:
+            chklogger.logger.warning("Couldn't process patch callsite %s", pc)
             continue
-        buffersize = stackbuffer.size
-        basicblock = fn.block(pc.baddr)
-        spare = find_spare_instruction(basicblock, instr.iaddr)
-
-        print("  " + pc.instr.iaddr + "  " + pc.instr.annotation)
-        print("  - faddr: " + pc.faddr)
-        print("  - iaddr: " + pc.instr.iaddr)
-        print("  - target function: " + str(pc.summary.name))
-        print("  - stack offset: " + str(dstoffset))
-        print("  - length argument: " + str(pc.lenarg))
-        print("  - buffersize: " + str(buffersize))
-        print("  - spare: " + str(spare))
+
+        patch_records.append(jresult.content)
+
+    content["patch-records"] = patch_records
+    chklogger.logger.debug("Number of patch callsites: %s", len(content['patch-records']))
+
+    if xjson:
+        jcontent = JSONResult("patchcandidates", content, "ok")
+        write_json_result(xoutput, jcontent, "patchcandidates")
+        exit(0)
+
+    for patch_record in content["patch-records"]:
+        print("  " + patch_record['iaddr'] + "  " + patch_record['annotation'])
+        print("  - faddr: %s" % patch_record['faddr'])
+        print("  - iaddr: %s" % patch_record['iaddr'])
+        print("  - target function: %s" % patch_record['target-function'])
+        print("  - stack offset: %s" % patch_record['stack-offset'])
+        print("  - length argument: %s" % patch_record['length-argument'])
+        print("  - buffersize: %s" % patch_record['buffersize'])
+        print("  - spare: %s" % patch_record['spare'])
         print("")
 
-    print("Number of patch callsites: " + str(len(patchcallsites)))
+    print("Generated %d patch records from %d library calls" %
+          (len(content['patch-records']), n_calls))
 
     exit(0)