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@nosoop
Created February 5, 2019 23:00
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makesig.idc with fixes for IDA 7.0
#include <idc.idc>
/* makesig.idc: IDA script to automatically create and wildcard a function signature.
* Copyright 2014, Asher Baker
*
* This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
*
* 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
*
* 3. This notice may not be removed or altered from any source distribution.
*/
static main()
{
Wait(); // We won't work until autoanalysis is complete
SetStatus(IDA_STATUS_WORK);
auto pAddress = ScreenEA();
pAddress = GetFunctionAttr(pAddress, FUNCATTR_START);
if (pAddress == BADADDR) {
Warning("Make sure you are in a function!");
SetStatus(IDA_STATUS_READY);
return;
}
auto name = Name(pAddress);
auto sig = "", found = 0;
auto pFunctionEnd = GetFunctionAttr(pAddress, FUNCATTR_END);
while (pAddress != BADADDR) {
auto pInfo = DecodeInstruction(pAddress);
if (!pInfo) {
Warning("Something went terribly wrong D:");
SetStatus(IDA_STATUS_READY);
return;
}
// isCode(GetFlags(pAddress)) == Opcode
// isTail(GetFlags(pAddress)) == Operand
// ((GetFlags(pAddress) & MS_CODE) == FF_IMMD) == :iiam:
auto bDone = 0;
if (pInfo.n == 1) {
if (pInfo.Op0.type == o_near || pInfo.Op0.type == o_far) {
if (Byte(pAddress) == 0x0F) { // Two-byte instruction
sig = sig + sprintf("0F %02X ", Byte(pAddress + 1)) + PrintWildcards(GetDTSize(pInfo.Op0.dtype));
} else {
sig = sig + sprintf("%02X ", Byte(pAddress)) + PrintWildcards(GetDTSize(pInfo.Op0.dtype));
}
bDone = 1;
}
}
if (!bDone) { // unknown, just wildcard addresses
auto i = 0, itemSize = ItemSize(pAddress);
for (i = 0; i < itemSize; i++) {
auto pLoc = pAddress + i;
if ((GetFixupTgtType(pLoc) & FIXUP_MASK) == FIXUP_OFF32) {
sig = sig + PrintWildcards(4);
i = i + 3;
} else {
sig = sig + sprintf("%02X ", Byte(pLoc));
}
}
}
if (IsGoodSig(sig)) {
found = 1;
break;
}
pAddress = NextHead(pAddress, pFunctionEnd);
}
if (found == 0) {
Warning("Ran out of bytes to create unique signature.");
SetStatus(IDA_STATUS_READY);
return;
}
auto len = strlen(sig) - 1, smsig = "\\x";
for (i = 0; i < len; i++) {
auto c = substr(sig, i, i + 1);
if (c == " ") {
smsig = smsig + "\\x";
} else if (c == "?") {
smsig = smsig + "2A";
} else {
smsig = smsig + c;
}
}
Message("Signature for %s:\n%s\n%s\n", name, sig, smsig);
SetStatus(IDA_STATUS_READY);
return;
}
static GetDTSize(dtyp)
{
if (dtyp == dt_byte) {
return 1;
} else if (dtyp == dt_word) {
return 2;
} else if (dtyp == dt_dword) {
return 4;
} else if (dtyp == dt_float) {
return 4;
} else if (dtyp == dt_double) {
return 8;
} else {
Warning("Unknown type size (%d)", dtyp);
return -1;
}
}
static PrintWildcards(count)
{
auto i = 0, string = "";
for (i = 0; i < count; i++) {
string = string + "? ";
}
return string;
}
static IsGoodSig(sig)
{
auto count = 0, addr;
addr = FindBinary(addr, SEARCH_DOWN|SEARCH_NEXT, sig);
while (count <= 2 && addr != BADADDR) {
count = count + 1;
addr = FindBinary(addr, SEARCH_DOWN|SEARCH_NEXT, sig);
}
//Message("%s(%d)\n", sig, count);
return (count == 1);
}
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