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StringData record

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This commit is contained in:
caheckman 2020-04-21 15:36:18 -04:00
parent 1529e635fc
commit 7dee97339c
9 changed files with 141 additions and 88 deletions
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93
Ghidra/Features/Decompiler/src/decompile/cpp/stringmanage.cc
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@ -16,11 +16,11 @@
#include "stringmanage.hh"
#include "architecture.hh"
/// \param max is the maximum number of bytes to allow in a decoded string
/// \param max is the maximum number of characters to allow before truncating string
StringManager::StringManager(int4 max)
{
maximumBytes = max;
maximumChars = max;
}
StringManager::~StringManager(void)
@ -78,7 +78,8 @@ void StringManager::writeUtf8(ostream &s,int4 codepoint)
bool StringManager::isString(const Address &addr,Datatype *charType)
{
const vector<uint1> &buffer(getStringData(addr,charType));
bool isTrunc; // unused here
const vector<uint1> &buffer(getStringData(addr,charType,isTrunc));
return !buffer.empty();
}
@ -89,14 +90,16 @@ void StringManager::saveXml(ostream &s) const
{
s << "<stringmanage>\n";
map<Address,vector<uint1> >::const_iterator iter1;
map<Address,StringData>::const_iterator iter1;
for(iter1=stringMap.begin();iter1!=stringMap.end();++iter1) {
s << "<string>\n";
(*iter1).first.saveXml(s);
const vector<uint1> &vec( (*iter1).second );
s << " <bytes>\n" << setfill('0');
for(int4 i=0;vec.size();++i) {
s << hex << setw(2) << (int4)vec[i];
const StringData &stringData( (*iter1).second );
s << " <bytes";
a_v_b(s, "trunc", stringData.isTruncated);
s << ">\n" << setfill('0');
for(int4 i=0;stringData.byteData.size();++i) {
s << hex << setw(2) << (int4)stringData.byteData[i];
if (i%20 == 19)
s << "\n ";
}
@ -116,7 +119,8 @@ void StringManager::restoreXml(const Element *el,const AddrSpaceManager *m)
iter = list.begin();
Address addr = Address::restoreXml(*iter, m);
++iter;
vector<uint1> &vec(stringMap[addr]);
StringData &stringData(stringMap[addr]);
stringData.isTruncated = xml_readbool((*iter)->getAttributeValue("trunc"));
istringstream is((*iter)->getContent());
int4 val;
char c1, c2;
@ -137,7 +141,7 @@ void StringManager::restoreXml(const Element *el,const AddrSpaceManager *m)
else
c2 = c2 + 10 - 'a';
val = c1 * 16 + c2;
vec.push_back((uint1) val);
stringData.byteData.push_back((uint1) val);
is >> ws;
c1 = is.get();
c2 = is.get();
@ -267,15 +271,19 @@ StringManagerUnicode::~StringManagerUnicode(void)
delete [] testBuffer;
}
const vector<uint1> &StringManagerUnicode::getStringData(const Address &addr,Datatype *charType)
const vector<uint1> &StringManagerUnicode::getStringData(const Address &addr,Datatype *charType,bool &isTrunc)
{
map<Address,vector<uint1> >::iterator iter;
map<Address,StringData>::iterator iter;
iter = stringMap.find(addr);
if (iter != stringMap.end())
return (*iter).second;
if (iter != stringMap.end()) {
isTrunc = (*iter).second.isTruncated;
return (*iter).second.byteData;
}
vector<uint1> &vec(stringMap[addr]); // Allocate (initially empty) byte vector
StringData &stringData(stringMap[addr]); // Allocate (initially empty) byte vector
stringData.isTruncated = false;
isTrunc = false;
int4 curBufferSize = 0;
int4 charsize = charType->getSize();
@ -285,11 +293,12 @@ const vector<uint1> &StringManagerUnicode::getStringData(const Address &addr,Dat
do {
int4 amount = 32; // Grab 32 bytes of image at a time
uint4 newBufferSize = curBufferSize + amount;
if (newBufferSize > maximumBytes) {
newBufferSize = maximumBytes;
if (newBufferSize > maximumChars) {
newBufferSize = maximumChars;
amount = newBufferSize - curBufferSize;
if (amount == 0)
break;
if (amount == 0) {
return stringData.byteData; // Could not find terminator
}
}
glb->loader->loadFill(testBuffer + curBufferSize, amount,
addr + curBufferSize);
@ -298,52 +307,56 @@ const vector<uint1> &StringManagerUnicode::getStringData(const Address &addr,Dat
curBufferSize = newBufferSize;
} while (!foundTerminator);
} catch (DataUnavailError &err) {
return vec; // Return the empty buffer
return stringData.byteData; // Return the empty buffer
}
if (charsize == 1) {
if (!isCharacterConstant(testBuffer,curBufferSize,charsize))
return vec; // Return the empty buffer
vec.reserve(curBufferSize);
vec.assign(testBuffer,testBuffer+curBufferSize);
int4 numChars = checkCharacters(testBuffer, curBufferSize, charsize);
if (numChars < 0)
return stringData.byteData; // Return the empty buffer (invalid encoding)
if (charsize == 1 && numChars < maximumChars) {
stringData.byteData.reserve(curBufferSize);
stringData.byteData.assign(testBuffer,testBuffer+curBufferSize);
}
else {
// We need to translate to UTF8
// We need to translate to UTF8 and/or truncate
ostringstream s;
if (!writeUnicode(s, testBuffer, curBufferSize, charsize))
return vec; // Return the empty buffer
return stringData.byteData; // Return the empty buffer
string resString = s.str();
int4 newSize = resString.size();
if (newSize > maximumBytes)
newSize = maximumBytes;
vector<uint1> &vec(stringMap[addr]);
vec.reserve(newSize);
stringData.byteData.reserve(newSize + 1);
const uint1 *ptr = (const uint1 *)resString.c_str();
vec.assign(ptr,ptr+newSize);
stringData.byteData.assign(ptr,ptr+newSize);
stringData.byteData[newSize] = 0; // Make sure there is a null terminator
}
return vec;
stringData.isTruncated = (numChars >= maximumChars);
isTrunc = stringData.isTruncated;
return stringData.byteData;
}
/// Check that the given buffer contains valid unicode.
/// If the string is encoded in UTF8 or ASCII, we get (on average) a bit of check
/// per character. For UTF16, the surrogate reserved area gives at least some check.
/// \param buf is the byte array to check
/// \param size is the size of the buffer in bytes
/// \param charsize is the UTF encoding (1=UTF8, 2=UTF16, 4=UTF32)
/// \return \b true if the buffer is filled with valid unicode
bool StringManagerUnicode::isCharacterConstant(const uint1 *buf,int4 size,int4 charsize) const
/// \return the number of characters or -1 if there is an invalid encoding
int4 StringManagerUnicode::checkCharacters(const uint1 *buf,int4 size,int4 charsize) const
{
if (buf == (const uint1 *)0) return false;
if (buf == (const uint1 *)0) return -1;
bool bigend = glb->translate->isBigEndian();
int4 i=0;
int4 count=0;
int4 skip = charsize;
while(i<size) {
int4 codepoint = getCodepoint(buf+i,charsize,bigend,skip);
if (codepoint < 0) return false;
if (codepoint < 0) return -1;
if (codepoint == 0) break;
count += 1;
i += skip;
}
return true;
return count;
}
/// Assume the buffer contains a null terminated unicode encoded string.
@ -358,6 +371,7 @@ bool StringManagerUnicode::writeUnicode(ostream &s,uint1 *buffer,int4 size,int4
{
bool bigend = glb->translate->isBigEndian();
int4 i=0;
int4 count=0;
int4 skip = charsize;
while(i<size) {
int4 codepoint = getCodepoint(buffer+i,charsize,bigend,skip);
@ -365,6 +379,9 @@ bool StringManagerUnicode::writeUnicode(ostream &s,uint1 *buffer,int4 size,int4
if (codepoint == 0) break; // Terminator
writeUtf8(s, codepoint);
i += skip;
count += 1;
if (count >= maximumChars)
break;
}
return true;
}