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/*
* SMPStaticAnalyzer.cpp - <see below>.
*
* Copyright (c) 2000, 2001, 2010 - University of Virginia
*
* This file is part of the Memory Error Detection System (MEDS) infrastructure.
* This file may be used and modified for non-commercial purposes as long as
* all copyright, permission, and nonwarranty notices are preserved.
* Redistribution is prohibited without prior written consent from the University
* of Virginia.
*
* Please contact the authors for restrictions applying to commercial use.
*
* THIS SOURCE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* Author: University of Virginia
* e-mail: jwd@virginia.com
* URL : http://www.cs.virginia.edu/
*
* Additional copyrights 2010, 2011 by Zephyr Software LLC
* e-mail: {clc,jwd}@zephyr-software.com
* URL : http://www.zephyr-software.com/
//
// SMPStaticAnalyzer.cpp
//
// This plugin performs the static analyses needed for the SMP project
// (Software Memory Protection).
//
using namespace std;
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#include <list>
#include <vector>
#include <string>
#include <ida.hpp>
#include <idp.hpp>
#include <allins.hpp>
#include <auto.hpp>
#include <bytes.hpp>
#include <funcs.hpp>
#include <intel.hpp>
#include <loader.hpp>
#include <lines.hpp>
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#include <nalt.hpp>
#include <name.hpp>
#include <ua.hpp>
#include "SMPStaticAnalyzer.h"
#include "SMPDataFlowAnalysis.h"
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#include "SMPProgram.h"
#include "SMPFunction.h"
#include "SMPInstr.h"
#include "ProfilerInformation.h"
// Set to 1 for debugging output
#define SMP_DEBUG 1
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#define SMP_DEBUG2 0 // verbose
#define SMP_DEBUG3 0 // verbose
#define SMP_DEBUG_MEM 0 // print memory operands
#define SMP_DEBUG_TYPE0 0 // Output instr info for OptType = 0
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#define SMP_DEBUG_CHUNKS 0 // restructuring tail chunks, shared chunks, etc.
#define SMP_DEBUG_DATA_ONLY 0 // Find & fix data addresses in code segments
// Set to 1 when doing a binary search using SMP_DEBUG_COUNT to find
// which function is causing a problem.
#define SMP_BINARY_DEBUG 0
#define SMP_DEBUG_COUNT 356 // How many funcs to process in problem search
int FuncsProcessed = 0;
#define SMP_FIXUP_IDB 0 // Try to fix the IDA database?
#define SMP_DEBUG_FIXUP_IDB 0 // debugging output for FixupIDB chain
#define SMP_FIND_ORPHANS 1 // find code outside of functions
#define SMP_DEBUG_CODE_ORPHANS 1 // Detect whether we are causing code to be orphaned
#if SMP_DEBUG_CODE_ORPHANS
set<ea_t> CodeOrphans;
#endif
// Define optimization categories for instructions.
int OptCategory[NN_last + 1];
// Initialize the OptCategory[] array.
void InitOptCategory(void);
// Record which opcodes change the stack pointer, and by how many
// bytes up (reduction in stack size for stacks that grow downward)
// or down (increase in stack size for stacks that grow downward).
sval_t StackAlteration[NN_last + 1];
// Initialize the StackAlteration[] array.
void InitStackAlteration(void);
// Keep statistics on how many instructions we saw in each optimization
// category, and how many optimizing annotations were emitted for
// each category.
int OptCount[LAST_OPT_CATEGORY + 1];
int AnnotationCount[LAST_OPT_CATEGORY + 1];
// Unique data referent number to use in data annotations.
unsigned long DataReferentID;
// Debugging counters for analyzing memory usage.
unsigned long UnusedInstrCount;
unsigned long UnusedBlockCount;
unsigned long UnusedStructCount;
unsigned long UnusedIntCount;
#if SMP_COUNT_MEMORY_ALLOCATIONS
// Counters for analyzing memory use for allocated and used objects.
unsigned long SMPInstCount;
unsigned long SMPBlockCount;
unsigned long SMPFuncCount;
unsigned long SMPGlobalVarCount;
unsigned long SMPLocalVarCount;
unsigned long SMPDefUseChainCount;
unsigned long SMPInstBytes;
unsigned long SMPDefUseChainBytes;
// The types of data objects based on their first operand flags.
const char *DataTypes[] = { "VOID", "NUMHEX", "NUMDEC", "CHAR",
"SEG", "OFFSET", "NUMBIN", "NUMOCT", "ENUM", "FORCED",
"STRUCTOFFSET", "STACKVAR", "NUMFLOAT", "UNKNOWN",
"UNKNOWN", "UNKNOWN", 0};
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// Filename (not including path) of executable being analyzed.
static char RootFileName[MAXSTR];
// strings for printing ZST_SysCallType
const char *CallTypeNames[4] = { "Unrestricted", "High-Privilege", "File-Access", "Network-Access" };
DisAsmString DisAsmText;
// Operand type that can have all fields initialized to o_void and zero
// values, to be used to copy-initialize operands that we are adding to
// RTLs and DEF and USE lists.
op_t InitOp;
// File foo.exe.alarms for Zephyr Security Toolkit security alarm messages.
FILE *ZST_AlarmFile;
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// Code addresses identified by a disassembler, such as objdump on
// Linux. These can be used to improve the code vs. data identification
// of IDA Pro.
vector<ea_t> DisasmLocs;
// Code addresses as identified by IDA Pro, to be compared to DisasmLocs.
vector<ea_t> IDAProLocs;
// Function start and end addresses (for function entry chunks only).
// Kept here because IDA Pro 5.1 seems to have a memory overwriting
// problem when iterating through all functions in the program. An existing
// func_t *ChunkInfo data structure was getting overwritten by one of the
// function func_t data structures, causing changes of startEA and endEA among
// other things.
struct SMP_bounds_t {
ea_t startEA;
ea_t endEA;
};
vector<SMP_bounds_t> FuncBounds;
// List of functions that need to be reanalyzed after all the code fixup
// and code discovery is complete. Kept as a list of addresses; any address
// within the function is good enough to designate it.
list<ea_t> FuncReanalyzeList;
// A code region that has been converted from data but has code addresses that
// need to be reanalyzed. This is usually because a former data address is
// now a jump to a code target that is still a data address. We have to wait
// until the target has become code before IDA will accept the jump as valid.
class FixupRegion {
public:
FixupRegion(SMP_bounds_t);
inline ea_t GetStart(void) const { return CodeRegion.startEA; };
inline ea_t GetEnd(void) const { return CodeRegion.endEA; };
inline void SetStart(ea_t addr) { CodeRegion.startEA = addr; };
list<ea_t> FixupInstrs; // easier to expose than to encapsulate
private:
SMP_bounds_t CodeRegion;
};
FixupRegion::FixupRegion(SMP_bounds_t Range) {
this->CodeRegion = Range;
return;
}
// List of code regions that were not completely analysed because of jump to
// data considerations.
list<FixupRegion> CodeReanalyzeList;
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// Map library function names to their system call type.
map<string, ZST_SysCallType> ZST_FuncTypeMap;
// Map system call types to their Zephyr Security Toolkit security policy.
map<ZST_SysCallType, ZST_Policy> ZST_TypePolicyMap;
// Set of whitelisted file locations.
set<string> ZST_FileLocWhitelist;
// Set of whitelisted network locations.
set<string> ZST_NetworkLocWhitelist;
// Set of blacklisted file locations.
set<string> ZST_FileLocBlacklist;
// Set of blacklisted network locations.
set<string> ZST_NetworkLocBlacklist;
void IDAP_run(int);
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// Functions for diagnosing and/or fixing problems in the IDA database.
void FixupIDB(void); // Driver for all other fixing functions.
void FindDataInCode(void);
void AuditTailChunkOwnership(void);
void FindOrphanedCode(segment_t *, FILE *, FILE *);
void Debug_FindOrphanedCode(segment_t *, bool);
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void FixCodeIdentification(void);
int FixupNewCodeChunks(void);
void AuditCodeTargets(void);
ea_t FindNewFuncLimit(ea_t);
void SpecialDebugOutput(void);
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void RemoveIDACodeAddr(ea_t);
void ZST_InitPolicies(const char *);
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static int idaapi idp_callback(void *, int event_id, va_list va) {
if (event_id == ph.auto_empty_finally) { // IDA analysis is done
IDAP_run(0);
qexit(0);
}
return 0;
}
int IDAP_init(void) {
#if 0 // We are now calling from the SMP.idc script.
// Skip this plugin if it was not specified by the user on the
// command line.
if (get_plugin_options("SMPStaticAnalyzer") == NULL) {
msg("IDAP_init point 2.\n");
return PLUGIN_SKIP;
}
#endif
// Ensure correct working environment.
if ((inf.filetype != f_ELF) && (inf.filetype != f_PE)) {
error("Executable format must be PE or ELF.");
return PLUGIN_SKIP;
}
if (ph.id != PLFM_386) {
error("Processor must be x86.");
return PLUGIN_SKIP;
}
hook_to_notification_point(HT_IDP, idp_callback, NULL);
DataReferentID = 1;
UnusedStructCount = 0;
UnusedIntCount = 0;
#if SMP_COUNT_MEMORY_ALLOCATIONS
SMPInstCount = 0;
SMPBlockCount = 0;
SMPDefUseChainCount = 0;
SMPFuncCount = 0;
SMPGlobalVarCount = 0;
SMPLocalVarCount = 0;
SMPInstBytes = 0;
SMPDefUseChainBytes = 0;
InitOp.type = o_void;
InitOp.addr = 0;
InitOp.dtyp = dt_dword;
InitOp.flags = 0;
InitOp.n = 0;
InitOp.offb = 0;
InitOp.offo = 0;
InitOp.reg = R_none;
InitOp.specflag1 = 0;
InitOp.specflag2 = 0;
InitOp.specflag3 = 0;
InitOp.specflag4 = 0;
InitOp.specval = 0;
InitOp.value = 0;
ZST_AlarmFile = NULL;
InitOptCategory();
InitDFACategory();
InitTypeCategory();
InitSMPDefsFlags();
InitSMPUsesFlags();
InitLibFuncFGInfoMaps();
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InitIntegerErrorCallSinkMap();
return PLUGIN_KEEP;
} // end of IDAP_init
void IDAP_term(void) {
unhook_from_notification_point(HT_IDP, idp_callback, NULL);
return;
}
void IDAP_run(int arg) {
FILE *AnnotFile;
FILE *InfoAnnotFile;
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#if SMP_DEBUG
msg("Beginning IDAP_run.\n");
#endif
msg("IDA SDK version: %d \n", IDA_SDK_VERSION);
// Open the output file.
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ssize_t FileLen;
FileLen = get_root_filename(RootFileName, sizeof(RootFileName) - 1);
string AnnotFileName(RootFileName);
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string FileSuffix(".annot");
AnnotFileName += FileSuffix;
string InfoAnnotFileName(RootFileName);
string InfoFileSuffix(".infoannot");
InfoAnnotFileName += InfoFileSuffix;
string ZSTPolicyFileName(RootFileName);
string PolicyFileSuffix(".policy");
ZSTPolicyFileName += PolicyFileSuffix;
string ZSTAlarmFileName(RootFileName);
string AlarmFileSuffix(".alarms");
ZSTAlarmFileName += AlarmFileSuffix;
ea_t RecentAddr;
#if SMP_DEBUG_CODE_ORPHANS
CodeOrphans.clear();
RecentAddr = BADADDR;
#if IDA_SDK_VERSION < 600
for (int SegIndex = 0; SegIndex < get_segm_qty(); ++SegIndex) {
segment_t *seg = getnseg(SegIndex);
#else
for (segment_t *seg = get_first_seg(); NULL != seg; seg = get_next_seg(RecentAddr)) {
RecentAddr = seg->startEA;
#endif
if (seg->type == SEG_CODE)
Debug_FindOrphanedCode(seg, true);
}
#endif
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SMPProgram *CurrProg = new SMPProgram();
CurrProg->AnalyzeData(); // Analyze static data in the executable
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// read the Profiler generated information into a new prof_info class
ProfilerInformation *prof_info = new ProfilerInformation(AnnotFileName.c_str(), CurrProg);
AnnotFile = qfopen(AnnotFileName.c_str(), "w");
if (NULL == AnnotFile) {
error("FATAL ERROR: Cannot open output file %s\n", AnnotFileName.c_str());
delete prof_info;
return;
}
InfoAnnotFile = qfopen(InfoAnnotFileName.c_str(), "w");
if (NULL == InfoAnnotFile) {
error("FATAL ERROR: Cannot open output file %s\n", InfoAnnotFileName.c_str());
return;
}
ZST_AlarmFile = qfopen(ZSTAlarmFileName.c_str(), "w");
if (NULL == ZST_AlarmFile) {
error("FATAL ERROR: Cannot open security alarms file %s\n", ZSTAlarmFileName.c_str());
delete prof_info;
return;
}
// Read the Zephyr Security Toolkit system call security policies, if available.
ZST_InitPolicies(ZSTPolicyFileName.c_str());
(void) memset(OptCount, 0, sizeof(OptCount));
(void) memset(AnnotationCount, 0, sizeof(AnnotationCount));
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// Record the start and end addresses for all function entry
// chunks in the program.
FuncBounds.reserve(10 + get_func_qty());
for (size_t FuncIndex = 0; FuncIndex < get_func_qty(); ++FuncIndex) {
func_t *FuncInfo = getn_func(FuncIndex);
SMP_bounds_t temp;
temp.startEA = FuncInfo->startEA;
temp.endEA = FuncInfo->endEA;
FuncBounds.push_back(temp);
}
#if SMP_DEBUG_DATA_ONLY
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qfclose(SymsFile);
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return;
#endif
// Pre-audit the IDA database by seeing if the distinction
// between code and data can be improved, and if all branches
// and calls have proper code targets and code cross references.
#if SMP_FIXUP_IDB
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#endif
if (0 < prof_info->GetProfilerAnnotationCount()) {
msg("Calling InferDataGranularity\n");
msg("ptr to MemoryAccessInfo: %p\n", prof_info->GetMemoryAccessInfo());
prof_info->GetMemoryAccessInfo()->InferDataGranularity();
msg("Returned from InferDataGranularity\n");
}
CurrProg->ProfGranularityFinished(AnnotFile, InfoAnnotFile);
CurrProg->EmitAnnotations(AnnotFile, InfoAnnotFile);
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#if SMP_DEBUG_CODE_ORPHANS
RecentAddr = BADADDR;
#if IDA_SDK_VERSION < 600
for (int SegIndex = 0; SegIndex < get_segm_qty(); ++SegIndex) {
segment_t *seg = getnseg(SegIndex);
#else
for (segment_t *seg = get_first_seg(); NULL != seg; seg = get_next_seg(RecentAddr)) {
RecentAddr = seg->startEA;
#endif
if (seg->type == SEG_CODE)
Debug_FindOrphanedCode(seg, true);
}
#endif
RecentAddr = BADADDR;
#if IDA_SDK_VERSION < 600
for (int SegIndex = 0; SegIndex < get_segm_qty(); ++SegIndex) {
segment_t *seg = getnseg(SegIndex);
#else
for (segment_t *seg = get_first_seg(); NULL != seg; seg = get_next_seg(RecentAddr)) {
RecentAddr = seg->startEA;
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if (seg->type == SEG_CODE)
FindOrphanedCode(seg, AnnotFile, InfoAnnotFile);
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}
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for (int OptType = 0; OptType <= LAST_OPT_CATEGORY; ++OptType) {
msg("Optimization Category Count %d: %d Annotations: %d\n",
OptType, OptCount[OptType], AnnotationCount[OptType]);
}
qfclose(AnnotFile);
qfclose(InfoAnnotFile);
qfclose(ZST_AlarmFile);
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delete CurrProg;
return;
} // end IDAP_run()
char IDAP_comment[] = "ZephyrSoftware STARS (Static Analyzer for Reliability and Security)";
char IDAP_help[] = "Good luck";
char IDAP_name[] = "SMPStaticAnalyzer";
char IDAP_hotkey[] = "Alt-J";
plugin_t PLUGIN = {
IDP_INTERFACE_VERSION,
0,
IDAP_init,
IDAP_term,
IDAP_run,
IDAP_comment,
IDAP_help,
IDAP_name,
IDAP_hotkey
};
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// Find all code addresses in the IDA database and enter them into
// IDAProLocs. Find all code addresses identified by the external
// disassembler (e.g. objdump) and enter them into DisasmLocs.
void FindCodeAddresses(void) {
// Read in code addresses as found by an external disassembler.
ea_t CurrDisasmAddr;
string DisasmFileName(RootFileName);
string FileSuffix(".SMPobjdump");
DisasmFileName += FileSuffix;
FILE *DisasmFile = qfopen(DisasmFileName.c_str(), "r");
if (NULL == DisasmFile) {
error("FATAL: Cannot open input file %s\n", DisasmFileName.c_str());
return;
}
#define DISASM_RESERVE_SIZE 50000
DisasmLocs.reserve(DISASM_RESERVE_SIZE);
int ScanReturn = qfscanf(DisasmFile, "%x", &CurrDisasmAddr);
while (1 == ScanReturn) {
int NextChar;
DisasmLocs.push_back(CurrDisasmAddr);
// Swallow the rest of the input line and get the next address.
do {
NextChar = qfgetc(DisasmFile);
} while ((EOF != NextChar) && ('\n' != NextChar));
ScanReturn = qfscanf(DisasmFile, "%x", &CurrDisasmAddr);
} // end while (1 == ScanReturn)
if (0 >= DisasmLocs.size()) {
msg("ERROR: No addresses read from %s\n", DisasmFileName.c_str());
qfclose(DisasmFile);
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return;
}
else {
msg("%d Disasm addresses read from %s\n", DisasmLocs.size(),
DisasmFileName.c_str());
qfclose(DisasmFile);
}
// Find all the code locs in the IDA Pro database. As we find
// them, store them in IDAProLocs.
#if IDA_SDK_VERSION < 600
for (int SegIndex = 0; SegIndex < get_segm_qty(); ++SegIndex) {
segment_t *seg = getnseg(SegIndex);
#else
for (segment_t *seg = get_first_seg(); NULL != seg; seg = get_next_seg(RecentAddr)) {
RecentAddr = seg->startEA;
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if (SEG_CODE != seg->type)
continue;
for (ea_t addr = seg->startEA; addr < seg->endEA; addr = get_item_end(addr)) {
flags_t InstrFlags = getFlags(addr);
if (isHead(InstrFlags) && isCode(InstrFlags)) {
IDAProLocs.push_back(addr);
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if ((0x806cda4 <= addr) && (0x806cf99 >= addr))
msg("IDA code addr: %x\n", addr);
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} // end if (isHead(addr) && isCode(addr)
#if SMP_DEBUG_FIXUP_IDB
else if ((0x806cda4 <= addr) && (0x806cf99 >= addr)) {
if (!isHead(InstrFlags))
msg("Weirdness: not isHead at %x\n", addr);
if (isUnknown(InstrFlags)) {
msg("Weirdness: isUnknown at %x\n", addr);
}
}
#endif
} // end for (ea_t addr = seg->startEA; ...)
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return;
} // end FindCodeAddresses()
// Return true if addr is not a proper beginning address for an instruction.
// Return false otherwise.
// Currently, we claim that an instruction is misaligned if DisasmLocs does
// not contain it. This function is useful for dealing with errors in IDA
// code identification, in which a large code section is identified as data,
// but some instructions in the middle of the "data" are identified as
// code but IDA often starts on the wrong boundary in these cases.
bool IsCodeMisaligned(ea_t addr) {
// Do a binary search for addr within DisasmLocs, which is sorted
// in ascending address order because of the way in which it was
// generated.
size_t min = 0;
size_t max = DisasmLocs.size(); // don't access DisasmLocs[max]
size_t index = (min + max) / 2;
while (addr != DisasmLocs[index]) {
if (min >= (max - 1))
return true;
#if 0
msg("min: %d max: %d index: %d\n", min, max, index);
#endif
if (addr < DisasmLocs[index])
max = index;
else // must be addr > DisasmLocs[index];
min = index;
index = (min + max) / 2;
}
return false;
} // end of IsCodeMisaligned()
void RemoveIDACodeAddr(ea_t addr) {
// Do a binary search for addr within IDAProLocs, which is sorted
// in ascending address order because of the way in which it was
// generated. Delete the element of IDAProLocs if found.
size_t min = 0;
size_t max = IDAProLocs.size(); // don't access IDAProLocs[max]
size_t index = (min + max) / 2;
while (addr != IDAProLocs[index]) {
if (min >= (max - 1))
return;
#if 0
msg("min: %d max: %d index: %d\n", min, max, index);
#endif
if (addr < IDAProLocs[index])
max = index;
else // must be addr > IDAProLocs[index];
min = index;
index = (min + max) / 2;
}
// IDAProLocs[index] contains addr.
vector<ea_t>::iterator RemovalIterator = IDAProLocs.begin();
RemovalIterator += index;
RemovalIterator = IDAProLocs.erase(RemovalIterator);
return;
} // end of RemoveIDACodeAddr()
// Driver for all other fixing functions. Upon its return, the IDA
// database (IDB file) should be fixed up as much as we can fix it.
void FixupIDB(void) {
FindCodeAddresses();
#if SMP_DEBUG_FIXUP_IDB
SpecialDebugOutput();
#endif
AuditCodeTargets();
FindDataInCode();
AuditTailChunkOwnership();
if (DisasmLocs.size() > 0) {
FixCodeIdentification();
int fixes = FixupNewCodeChunks();
#if SMP_DEBUG_FIXUP_IDB
#endif
}
DisasmLocs.clear();
IDAProLocs.clear();
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} // end of FixupIDB()
// Find and print all data head addresses in code segments.
// If an isolated code instruction is found in the midst of a run
// of data bytes and has no code xrefs jumping to it, it is not
// reachable as code and is undoubtedly a mixup by IDA. Possibly
// the whole data region will be converted to code later, in which
// case the isolated code is not necessarily properly aligned and
// parsed at its present address, so we are glad to convert it into
// data anyway so that FindDataToConvert() will succeed on it later.
// Data to code conversion, and isolated code detection, are inhibited
// by IDA identifying several consecutive instructions in the midst
// of a data region, with the code addresses not agreeing with the
// external disassembler's code addresses. We will convert these
// misaligned instructions to data as we detect them. We will also
// convert unexplored bytes (isUnknown(flags) == true) into data if
// they are in the midst of a data sequence.
#define MIN_DATARUN_LEN 24 // #bytes on either side of "isolated" code
void FindDataInCode(void) {
size_t DataRunLen = 0; // How many data bytes in a row have we seen?
bool IsolatedCodeTrigger = false; // Have seen data, then isolated code
// Now looking for data
ea_t IsolatedCodeAddr;
int IsolatedCodeLen;
int InstrLen;
#if IDA_SDK_VERSION < 600
for (int SegIndex = 0; SegIndex < get_segm_qty(); ++SegIndex) {
segment_t *seg = getnseg(SegIndex);
#else
for (segment_t *seg = get_first_seg(); NULL != seg; seg = get_next_seg(RecentAddr)) {
RecentAddr = seg->startEA;
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if (SEG_CODE != seg->type)
continue;
#if SMP_DEBUG_FIXUP_IDB
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char SegName[MAXSTR];
ssize_t SegNameSize = get_segm_name(seg, SegName, sizeof(SegName) - 1);
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msg("Non-code addresses for code segment %s from %x to %x\n",
SegName, seg->startEA, seg->endEA);
#endif
for (ea_t addr = seg->startEA; addr < seg->endEA; addr = get_item_end(addr)) {
flags_t AddrFlags = getFlags(addr);
if (isHead(AddrFlags)) {
if (isData(AddrFlags)) {
DataRunLen += get_item_size(addr);
#if SMP_DEBUG_FIXUP_IDB
msg("Data: %x\n", addr);
#endif
if (MIN_DATARUN_LEN <= DataRunLen) {
if (IsolatedCodeTrigger) {
// Saw data, then one isolated code, then data
do_unknown_range(IsolatedCodeAddr, IsolatedCodeLen, DOUNK_SIMPLE);
RemoveIDACodeAddr(IsolatedCodeAddr);
if (do_data_ex(IsolatedCodeAddr, byteflag(),
IsolatedCodeLen, BADNODE)) {
msg("Converted isolated code to data: %x\n",
IsolatedCodeAddr);
}
else {
msg("Failed to convert isolated code to data: %x len: %x\n",
IsolatedCodeAddr, IsolatedCodeLen);
}
IsolatedCodeTrigger = false;
} // end if (IsolatedCodeTrigger)
} // end if (MIN_DATARUN_LEN <= DataRunLen)
} // end if (isData(AddrFlags)
else if (isUnknown(AddrFlags)) {
// Just in case; unknown usually means not head or tail
// If in a data run, convert to data.
InstrLen = get_item_size(addr);
clc5q
committed
msg("Unknown: %x len: %x\n", addr, InstrLen);
clc5q
committed
if (0 < DataRunLen) {
if (do_data_ex(addr, byteflag(), InstrLen, BADNODE)) {
clc5q
committed
msg("Converted unknown to data at %x len: %x\n", addr, InstrLen);
clc5q
committed
DataRunLen += InstrLen;
}
else {
clc5q
committed
msg("Failed to convert unknown to data at %x len: %x\n", addr, InstrLen);
clc5q
committed
DataRunLen = 0;
IsolatedCodeTrigger = false;
}
}
}
else if (isCode(AddrFlags)) { // must be true
if (MIN_DATARUN_LEN <= DataRunLen) {
clc5q
committed
msg("DataRunLen: %d at %x\n", DataRunLen, addr);
#if IDA_SDK_VERSION < 600
InstrLen = ua_ana0(addr);
#else
InstrLen = decode_insn(addr);
// We don't check the returned InstrLen for validity because IsCodeMisaligned()
// will check for validity immediately below.
clc5q
committed
#if SMP_DEBUG_FIXUP_IDB
msg("Calling IsCodeMisaligned: len %d\n", InstrLen);
#endif
if (IsCodeMisaligned(addr)) {
#if SMP_DEBUG_FIXUP_IDB
msg("Code was misaligned.\n");
#endif
do_unknown_range(addr, InstrLen, DOUNK_SIMPLE);
RemoveIDACodeAddr(addr);
if (do_data_ex(addr, byteflag(), InstrLen, BADNODE)) {
clc5q
committed
msg("Converted misaligned code to data at %x : len: %x\n",
addr, InstrLen);
clc5q
committed
// Step back so data gets processed.
DataRunLen += get_item_size(addr);
continue; // skip reset of DataRunLen
}
else {
clc5q
committed
msg("Misaligned code left as unknown at %x : len: %x\n",
addr, InstrLen);
clc5q
committed
IsolatedCodeTrigger = false;
}
} // end if (IsCodeMisaligned() ...)
else if (!hasRef(AddrFlags)) {
// No references at all --> isolated code.
IsolatedCodeTrigger = true;
IsolatedCodeAddr = addr;
IsolatedCodeLen = InstrLen;
}
else {
xrefblk_t xb;
clc5q
committed
bool ok = xb.first_to(addr, XREF_ALL);
clc5q
committed
if (!ok) {
// No code xrefs to this target addr.
IsolatedCodeTrigger = true;
IsolatedCodeAddr = addr;
IsolatedCodeLen = InstrLen;
}
}
} // end if (MIN_DATARUN_LEN <= DataRunLen)
else if (IsolatedCodeTrigger) {
// Two instructions in a row does not fit the pattern.
IsolatedCodeTrigger = false;
}
DataRunLen = 0;
} // end if (isData) ... else if (isUnknown) ... else isCode
} // end if (isHead)
else if (isUnknown(AddrFlags)) {
// If in a data run, convert to data.
InstrLen = get_item_size(addr);
clc5q
committed
msg("Unknown: %x len: %x\n", addr, InstrLen);
clc5q
committed
if (0 < DataRunLen) {
if (do_data_ex(addr, byteflag(), InstrLen, BADNODE)) {
clc5q
committed
msg("Converted unknown to data at %x len: %x\n", addr, InstrLen);
clc5q
committed
DataRunLen += InstrLen;
}
else {
clc5q
committed
msg("Failed to convert unknown to data at %x len: %x\n", addr, InstrLen);
clc5q
committed
DataRunLen = 0;
IsolatedCodeTrigger = false;
}
}
}
} // end for (ea_t addr = seg->startEA; ...)
clc5q
committed
return;
} // end of FindDataInCode()
// The choices that IDA makes for deciding which parent function of a
// TAIL chunk is the primary owner of the tail can be counterintuitive.
// A function entry can both fall into and jump to a tail chunk that
// is contiguous with it, yet the "owner" might be a function that is
// far below it in the executable address space. This function will
// change the ownership to a more sensible arrangement.
void AuditTailChunkOwnership(void) {
char FuncName[MAXSTR];
// Iterate through all chunks in the program.
size_t NumChunks = get_fchunk_qty();
for (size_t ChunkIndex = 0; ChunkIndex < NumChunks; ++ChunkIndex) {
clc5q
committed
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func_t *ChunkInfo = getn_fchunk((int) ChunkIndex);
if (is_func_tail(ChunkInfo)) {
// For each TAIL chunk, find all the parent chunks. Find the last
// parent chunk with an address less than the TAIL chunk address.
ea_t BestCandidate = 0;
func_parent_iterator_t FuncParent(ChunkInfo);
#if SMP_DEBUG_CHUNKS
msg("Tail chunk: %x ", ChunkInfo->startEA);
#endif
for (bool ok = FuncParent.first(); ok; ok = FuncParent.next()) {
ea_t parent = FuncParent.parent();
#if SMP_DEBUG_CHUNKS
msg(" parent: %x ", parent);
#endif
if ((parent > BestCandidate) && (parent < ChunkInfo->startEA))
BestCandidate = parent;
}
#if SMP_DEBUG_CHUNKS
msg("\n");
#endif
// Make the best parent chunk the owner of the TAIL chunk if it is
// not already the owner.
if (ChunkInfo->owner != BestCandidate) {
if (0 < BestCandidate) {
if (set_tail_owner(ChunkInfo, BestCandidate)) {
func_t *FuncInfo = get_func(BestCandidate);
msg("Set %x as new owner of tail %x\n",
BestCandidate, ChunkInfo->startEA);
// Reanalyze the parent function (and all its
// tail chunks) now that the structure has changed.
reanalyze_function(FuncInfo);
}
else {
msg("set_tail_owner failed for tail %x and parent %x\n",
ChunkInfo->startEA, BestCandidate);
}
}
else {
func_t *FuncInfo = get_func(ChunkInfo->owner);
get_func_name(FuncInfo->startEA, FuncName, sizeof(FuncName) - 1);
#if SMP_DEBUG_CHUNKS
msg("No good parent candidate before tail at %x\n",
ChunkInfo->startEA);
msg("Current parent is %x: %s\n", FuncInfo->startEA, FuncName);
#endif
// Find out if a function entry chunk that comes before the
// tail is a better candidate for the owner (i.e. it falls
// through to the tail, or jumps to it).
BestCandidate = 0;
#if SMP_DEBUG_CHUNKS
msg("Finding parent func candidates for %x:", ChunkInfo->startEA);
#endif
SMP_bounds_t CurrFunc;
for (size_t FuncIndex = 0; FuncIndex < FuncBounds.size(); ++FuncIndex) {
CurrFunc = FuncBounds[FuncIndex];
if ((CurrFunc.startEA < ChunkInfo->startEA)
&& (CurrFunc.startEA > BestCandidate)) {
BestCandidate = CurrFunc.startEA;
#if SMP_DEBUG_CHUNKS
msg(" candidate: %x tail: %x", BestCandidate,
ChunkInfo->startEA);
#endif
}
else {
#if SMP_DEBUG_CHUNKS
msg(" not a candidate: %x tail: %x best: %x\n",
CurrFunc.startEA, ChunkInfo->startEA, BestCandidate);
#endif
break;
}
} // end for (size_t FuncIndex = 0; ...)
if (0 >= BestCandidate) { // highly unlikely
msg("No good func entry parent candidate.\n");
}
else {
FuncInfo = get_func(BestCandidate);
get_func_name(FuncInfo->startEA, FuncName, sizeof(FuncName) - 1);
#if SMP_DEBUG_CHUNKS
msg("Best func entry parent candidate: %s at %x",
FuncName, BestCandidate);
if (FuncInfo->endEA == ChunkInfo->startEA)
msg(" Function endEA == tail chunk startEA");
msg("\n");
#endif
}
}
} // end if (ChunkInfo->owner != BestCandidate)
#if SMP_DEBUG_CHUNKS
else {
msg("Already best parent for %x is %x\n", ChunkInfo->startEA,
ChunkInfo->owner);
}
#endif
} // end if (is_func_tail(ChunkInfo))
} // end for (size_t ChunkIndex = 0; ...)
return;
} // end of AuditTailChunkOwnership()
// If the addresses signified from DisasmIndex to IDAProIndex are
// all considered data and do NOT follow a return instruction,
// return false and update AreaSize to reflect the area to be
// converted.
// Return value: true -> skip to IDAProIndex; false -> convert AreaSize bytes.
bool FindDataToConvert(size_t IDAProIndex, size_t DisasmIndex, int &AreaSize) {
ea_t PrevIDAAddr;
ea_t NextIDAAddr;
size_t ShadowDisasmIndex = DisasmIndex - 1;
ea_t DisasmAddr = DisasmLocs[ShadowDisasmIndex];
bool CannotConvert = false; // return value
bool DebugAddress = false;
#if SMP_DEBUG_FIXUP_IDB
DebugAddress = (DisasmAddr == 0x806c19a);
#endif
if (DebugAddress) {
msg("IDAProIndex: %d DisasmIndex: %d\n", IDAProIndex, DisasmIndex);
msg("IDA locs size %d Disasm locs size %d\n", IDAProLocs.size(),
DisasmLocs.size());
}
if (IDAProIndex >= IDAProLocs.size()) {
// Have already processed the last IDA address.
if (DebugAddress) msg(" Already done with IDAProLocs.\n");
return true;
}
else if (DisasmIndex >= DisasmLocs.size()) {
// Strange. Last Disasm address is only one to convert, and
// IDA still has addresses after that?
if (DebugAddress) msg(" Already done with DisasmLocs.\n");
return true;
}
else if (IDAProIndex < 2) {
// We have Disasm addrs before the very first IDA addr. We
// don't trust this boundary case.
if (DebugAddress) msg(" Boundary case with IDAProLocs.\n");
return true;
}
NextIDAAddr = IDAProLocs[IDAProIndex - 1];
PrevIDAAddr = IDAProLocs[IDAProIndex - 2];
if (DebugAddress) msg(" PrevIDAAddr: %x NextIDAAddr: %x\n", PrevIDAAddr, NextIDAAddr);
// See if previous IDA address was a return.
flags_t PrevFlags = getFlags(PrevIDAAddr);
if (!isCode(PrevFlags) || !isHead(PrevFlags)) {
msg("PrevIDAAddr %x not isCode or not isHead.\n", PrevIDAAddr);
return true;
}
SMPInstr PrevInstr(PrevIDAAddr);
PrevInstr.Analyze();
if (DebugAddress) msg("Finished PrevInstr.Analyze()\n");
if (PrevInstr.MDIsReturnInstr()) {
// Right after a return come no-ops and 2-byte no-ops
// that are just for alignment. IDA does not seem to be
// happy when we convert all those to code.
if (DebugAddress) msg(" Data followed a return instruction.\n");
return true;
}
// Now, see if the area from DisasmAddr to NextIDAAddr is all data
// according to IDA.
while (DisasmAddr < NextIDAAddr) {
flags_t DataFlags = getFlags(DisasmAddr);
if (isTail(DataFlags)) {
if (DebugAddress) msg(" tail byte: %x\n", DisasmAddr);
DisasmAddr = get_item_end(DisasmAddr);
}
else if (isData(DataFlags)) {
if (DebugAddress) msg(" data byte: %x\n", DisasmAddr);
DisasmAddr = get_item_end(DisasmAddr);
}
else if (isCode(DataFlags)) {
// How could this ever happen?
if (DebugAddress) msg(" isCode: %x\n", DisasmAddr);
return true;
}
else { // must be isUnknown()
// Very conservative here; only want to convert when the whole
// region is data, because that is a symptom of IDA missing
// a piece of code within a function (usually a piece of code
// that is only reachable via an indirect jump).
if (DebugAddress) msg(" Not isData: %x\n", DisasmAddr);
return true;
}
if (DebugAddress) msg(" new DisasmAddr: %x\n", DisasmAddr);
} // end while (DisasmAddr < NextIDAAddr)
if (DebugAddress) msg(" loop exit CannotConvert: %d\n", CannotConvert);