1

I have an instruction trace which is collected form a binary analysis platform and I already convert it to assembly instructions. I want to extract all functions and function calls in the file but unlike the IDA pro disassembly it does not include any hint about function start and end.
So my question is that how can I distinguish each function boundary, entry point and it's instructions. here is a small part of my output:

7c90e4f2:   sysenter 
7c9102d6:   cmpw   $0x5a4d,(%ecx)   I@0x00000000[0x00005a4d][2](R)  T0  M@0x7c800000[0x00005a4d][2](R)  T0
7c9102db:   jne    0x000000007c9102fa   J@0x00000000[0x0000001f][4](R)  T0
7c9102dd:   mov    0x3c(%ecx),%edx  M@0x7c80003c[0x000000f0][4](R)  T0  R@edx[0x7c90e4f4][4](W) T0
7c9102e0:   cmp    $0x10000000,%edx I@0x00000000[0x10000000][4](R)  T0  R@edx[0x000000f0][4](R) T0
7c9102e6:   jae    0x000000007c9102fa   J@0x00000000[0x00000014][4](R)  T0
7c9102e8:   lea    (%edx,%ecx,1),%eax   A@0x7c8000f0[0x00000000][4](R)  T0  R@eax[0x00000000][4](W) T0
7c9102eb:   mov    %eax,-0x1c(%ebp) R@eax[0x7c8000f0][4](R) T0  M@0x0022f758[0x00000010][4](W)  T0
7c9102ee:   cmpl   $0x4550,(%eax)   I@0x00000000[0x00004550][4](R)  T0  M@0x7c8000f0[0x00004550][4](R)  T0
7c9102f4:   jne    0x000000007c928c80   J@0x00000000[0x0001898c][4](R)  T0
7c9102fa:   orl    $0xffffffff,-0x4(%ebp)   I@0x00000000[0xffffffff][1](R)  T0  M@0x0022f770[0x00000000][4](RW) T0
7c9102fe:   call   0x000000007c90e8e6   J@0x00000000[0xffffe5e8][4](R)  T0  M@0x0022f748[0x7c9102c5][4](W)  T0
7c90e8e6:   mov    -0x10(%ebp),%ecx M@0x0022f764[0x0022f834][4](R)  T0  R@ecx[0x7c800000][4](W) T0
7c90e8e9:   mov    %ecx,%fs:0x0 R@ecx[0x0022f834][4](R) T0  M@0x7ffdf000[0x0022f764][4](W)  T0
7c90e8f0:   pop    %ecx M@0x0022f748[0x7c910303][4](R)  T0  R@ecx[0x0022f834][4](W) T0
7c90e8f1:   pop    %edi M@0x0022f74c[0x00000000][4](R)  T0  R@edi[0x00000000][4](W) T0
7c90e8f2:   pop    %esi M@0x0022f750[0x00000000][4](R)  T0  R@esi[0x00000000][4](W) T0
7c90e8f3:   pop    %ebx M@0x0022f754[0x00000000][4](R)  T0  R@ebx[0x00000000][4](W) T0
7c90e8f4:   leave   M@0x0022f774[0x0022f844][4](R)  T0  R@esp[0x0022f758][4](RW)    T0  R@ebp[0x0022f774][4](RW)    T0
7c90e8f5:   push   %ecx R@ecx[0x7c910303][4](R) T0  M@0x0022f774[0x0022f844][4](W)  T0
7c90e8f6:   ret     M@0x0022f774[0x7c910303][4](R)  T0
7c910303:   ret    $0x4 I@0x00000000[0x00000004][2](R)  T0  M@0x0022f778[0x7c91bd1b][4](R)  T0
7c91bd1b:   mov    %eax,-0x60(%ebp) R@eax[0x7c8000f0][4](R) T0  M@0x0022f7e4[0x7c910440][4](W)  T0
7c91bd1e:   cmp    %ebx,%eax    R@ebx[0x00000000][4](R) T0  R@eax[0x7c8000f0][4](R) T0
7c91bd20:   je     0x000000007c9407f4   J@0x00000000[0x00024ad4][4](R)  T0
7c91bd26:   lea    -0x34(%ebp),%eax A@0x0022f810[0x00000000][4](R)  T0  R@eax[0x7c8000f0][4](W) T0
7c91bd29:   push   %eax R@eax[0x0022f810][4](R) T0  M@0x0022f77c[0x7c800000][4](W)  T0
7c91bd2a:   push   $0xe I@0x00000000[0x0000000e][1](R)  T0  M@0x0022f778[0x7c91bd1b][4](W)  T0
7c91bd2c:   push   $0x1 I@0x00000000[0x00000001][1](R)  T0  M@0x0022f774[0x7c910303][4](W)  T0
7c91bd2e:   pushl  -0x1c(%ebp)  M@0x0022f828[0x7c800000][4](R)  T0  M@0x0022f770[0xffffffff][4](W)  T0
7c91bd31:   call   0x000000007c910326   J@0x00000000[0xffff45f5][4](R)  T0  M@0x0022f76c[0x7c910308][4](W)  T0
7c910326:   mov    %edi,%edi    R@edi[0x00000000][4](R) T0  R@edi[0x00000000][4](W) T0
7c910328:   push   %ebp R@ebp[0x0022f844][4](R) T0  M@0x0022f768[0x7c90e900][4](W)  T0
7c910329:   mov    %esp,%ebp    R@esp[0x0022f768][4](R) T0  R@ebp[0x0022f844][4](W) T0
7c91032b:   push   %ebx R@ebx[0x00000000][4](R) T0  M@0x0022f764[0x0022f834][4](W)  T0
7c91032c:   mov    0x8(%ebp),%ebx   M@0x0022f770[0x7c800000][4](R)  T0  R@ebx[0x00000000][4](W) T0
7c91032f:   test   $0x1,%bl I@0x00000000[0x00000001][1](R)  T0  R@bl[0x00000000][1](R)  T0
7c910332:   jne    0x000000007c9128f9   J@0x00000000[0x000025c7][4](R)  T0
7c910338:   push   %ebx R@ebx[0x7c800000][4](R) T0  M@0x0022f760[0x0022f828][4](W)  T0
7c910339:   call   0x000000007c9102b9   J@0x00000000[0xffffff80][4](R)  T0  M@0x0022f75c[0x0022f74c][4](W)  T0
7c9102b9:   push   $0xc I@0x00000000[0x0000000c][1](R)  T0  M@0x0022f758[0x7c8000f0][4](W)  T0
7c9102bb:   push   $0x7c910308  I@0x00000000[0x7c910308][4](R)  T0  M@0x0022f754[0x00000000][4](W)  T0
7c9102c0:   call   0x000000007c90e8ab   J@0x00000000[0xffffe5eb][4](R)  T0  M@0x0022f750[0x00000000][4](W)  T0
7c90e8ab:   push   $0x7c90e900  I@0x00000000[0x7c90e900][4](R)  T0  M@0x0022f74c[0x00000000][4](W)  T0
7c90e8b0:   mov    %fs:0x0,%eax M@0x7ffdf000[0x0022f834][4](R)  T0  R@eax[0x0022f810][4](W) T0
7c90e8b6:   push   %eax R@eax[0x0022f834][4](R) T0  M@0x0022f748[0x7c910303][4](W)  T0
7c90e8b7:   mov    0x10(%esp),%eax  M@0x0022f758[0x0000000c][4](R)  T0  R@eax[0x0022f834][4](W) T0
7c90e8bb:   mov    %ebp,0x10(%esp)  R@ebp[0x0022f768][4](R) T0  M@0x0022f758[0x0000000c][4](W)  T0
7c90e8bf:   lea    0x10(%esp),%ebp  A@0x0022f758[0x00000000][4](R)  T0  R@ebp[0x0022f768][4](W) T0
7c90e8c3:   sub    %eax,%esp    R@eax[0x0000000c][4](R) T0  R@esp[0x0022f748][4](RW)    T0
7c90e8c5:   push   %ebx R@ebx[0x7c800000][4](R) T0  M@0x0022f738[0x00000040][4](W)  T0
7c90e8c6:   push   %esi R@esi[0x00000000][4](R) T0  M@0x0022f734[0x0022f754][4](W)  T0
7c90e8c7:   push   %edi R@edi[0x00000000][4](R) T0  M@0x0022f730[0x00000008][4](W)  T0
7c90e8c8:   mov    -0x8(%ebp),%eax  M@0x0022f750[0x7c9102c5][4](R)  T0  R@eax[0x0000000c][4](W) T0
7c90e8cb:   mov    %esp,-0x18(%ebp) R@esp[0x0022f730][4](R) T0  M@0x0022f740[0x00000000][4](W)  T0
7c90e8ce:   push   %eax R@eax[0x7c9102c5][4](R) T0  M@0x0022f72c[0x00000018][4](W)  T0
7c90e8cf:   mov    -0x4(%ebp),%eax  M@0x0022f754[0x7c910308][4](R)  T0  R@eax[0x7c9102c5][4](W) T0
7c90e8d2:   movl   $0xffffffff,-0x4(%ebp)   I@0x00000000[0xffffffff][4](R)  T0  M@0x0022f754[0x7c910308][4](W)  T0
7c90e8d9:   mov    %eax,-0x8(%ebp)  R@eax[0x7c910308][4](R) T0  M@0x0022f750[0x7c9102c5][4](W)  T0
7c90e8dc:   lea    -0x10(%ebp),%eax A@0x0022f748[0x00000000][4](R)  T0  R@eax[0x7c910308][4](W) T0
7c90e8df:   mov    %eax,%fs:0x0 R@eax[0x0022f748][4](R) T0  M@0x7ffdf000[0x0022f834][4](W)  T0
7c90e8e5:   ret     M@0x0022f72c[0x7c9102c5][4](R)  T0
7c9102c5:   xor    %eax,%eax    R@eax[0x0022f748][4](R) T0  R@eax[0x0022f748][4](RW)    T0
7c9102c7:   mov    0x8(%ebp),%ecx   M@0x0022f760[0x7c800000][4](R)  T0  R@ecx[0x7c910303][4](W) T0
7c9102ca:   test   %ecx,%ecx    R@ecx[0x7c800000][4](R) T0  R@ecx[0x7c800000][4](R) T0
7c9102cc:   je     0x000000007c9102fe   J@0x00000000[0x00000032][4](R)  T0
7c9102ce:   cmp    $0xffffffff,%ecx I@0x00000000[0xffffffff][1](R)  T0  R@ecx[0x7c800000][4](R) T0
7c9102d1:   je     0x000000007c9102fe   J@0x00000000[0x0000002d][4](R)  T0
7c9102d3:   and    %eax,-0x4(%ebp)  R@eax[0x00000000][4](R) T0  M@0x0022f754[0xffffffff][4](RW) T0
7c9102d6:   cmpw   $0x5a4d,(%ecx)   I@0x00000000[0x00005a4d][2](R)  T0  M@0x7c800000[0x00005a4d][2](R)  T0
7c9102db:   jne    0x000000007c9102fa   J@0x00000000[0x0000001f][4](R)  T0
7c9102dd:   mov    0x3c(%ecx),%edx  M@0x7c80003c[0x000000f0][4](R)  T0  R@edx[0x000000f0][4](W) T0
7c9102e0:   cmp    $0x10000000,%edx I@0x00000000[0x10000000][4](R)  T0  R@edx[0x000000f0][4](R) T0
7c9102e6:   jae    0x000000007c9102fa   J@0x00000000[0x00000014][4](R)  T0
7c9102e8:   lea    (%edx,%ecx,1),%eax   A@0x7c8000f0[0x00000000][4](R)  T0  R@eax[0x00000000][4](W) T0
7c9102eb:   mov    %eax,-0x1c(%ebp) R@eax[0x7c8000f0][4](R) T0  M@0x0022f73c[0x00000000][4](W)  T0
7c9102ee:   cmpl   $0x4550,(%eax)   I@0x00000000[0x00004550][4](R)  T0  M@0x7c8000f0[0x00004550][4](R)  T0
7c9102f4:   jne    0x000000007c928c80   J@0x00000000[0x0001898c][4](R)  T0
7c9102fa:   orl    $0xffffffff,-0x4(%ebp)   I@0x00000000[0xffffffff][1](R)  T0  M@0x0022f754[0x00000000][4](RW) T0
7c9102fe:   call   0x000000007c90e8e6   J@0x00000000[0xffffe5e8][4](R)  T0  M@0x0022f72c[0x7c9102c5][4](W)  T0
7c90e8e6:   mov    -0x10(%ebp),%ecx M@0x0022f748[0x0022f834][4](R)  T0  R@ecx[0x7c800000][4](W) T0
7c90e8e9:   mov    %ecx,%fs:0x0 R@ecx[0x0022f834][4](R) T0  M@0x7ffdf000[0x0022f748][4](W)  T0
7c90e8f0:   pop    %ecx M@0x0022f72c[0x7c910303][4](R)  T0  R@ecx[0x0022f834][4](W) T0
7c90e8f1:   pop    %edi M@0x0022f730[0x00000000][4](R)  T0  R@edi[0x00000000][4](W) T0
7c90e8f2:   pop    %esi M@0x0022f734[0x00000000][4](R)  T0  R@esi[0x00000000][4](W) T0
7c90e8f3:   pop    %ebx M@0x0022f738[0x7c800000][4](R)  T0  R@ebx[0x7c800000][4](W) T0
7c90e8f4:   leave   M@0x0022f758[0x0022f768][4](R)  T0  R@esp[0x0022f73c][4](RW)    T0  R@ebp[0x0022f758][4](RW)    T0
7c90e8f5:   push   %ecx R@ecx[0x7c910303][4](R) T0  M@0x0022f758[0x0022f768][4](W)  T0
7c90e8f6:   ret     M@0x0022f758[0x7c910303][4](R)  T0
7c910303:   ret    $0x4 I@0x00000000[0x00000004][2](R)  T0  M@0x0022f75c[0x7c91033e][4](R)  T0
7c91033e:   test   %eax,%eax    R@eax[0x7c8000f0][4](R) T0  R@eax[0x7c8000f0][4](R) T0
7c910340:   je     0x000000007c912905   J@0x00000000[0x000025c5][4](R)  T0
7c910346:   mov    0x18(%eax),%cx   M@0x7c800108[0x0000010b][2](R)  T0  R@cx[0x00000303][2](W)  T0
7c91034a:   cmp    $0x10b,%cx   I@0x00000000[0x0000010b][2](R)  T0  R@cx[0x0000010b][2](R)  T0
7c91034f:   jne    0x000000007c947db0   J@0x00000000[0x00037a61][4](R)  T0
7c910355:   push   %eax R@eax[0x7c8000f0][4](R) T0  M@0x0022f760[0x7c800000][4](W)  T0
7c910356:   pushl  0x14(%ebp)   M@0x0022f77c[0x0022f810][4](R)  T0  M@0x0022f75c[0x7c91033e][4](W)  T0
7c910359:   pushl  0x10(%ebp)   M@0x0022f778[0x0000000e][4](R)  T0  M@0x0022f758[0x7c910303][4](W)  T0
7c91035c:   pushl  0xc(%ebp)    M@0x0022f774[0x00000001][4](R)  T0  M@0x0022f754[0xffffffff][4](W)  T0
7c91035f:   push   %ebx R@ebx[0x7c800000][4](R) T0  M@0x0022f750[0x7c910308][4](W)  T0
7c910360:   call   0x000000007c91036f   J@0x00000000[0x0000000f][4](R)  T0  M@0x0022f74c[0x7c90e900][4](W)  T0
7c91036f:   mov    %edi,%edi    R@edi[0x00000000][4](R) T0  R@edi[0x00000000][4](W) T0
7c910371:   push   %ebp R@ebp[0x0022f768][4](R) T0  M@0x0022f748[0x0022f834][4](W)  T0
7c910372:   mov    %esp,%ebp    R@esp[0x0022f748][4](R) T0  R@ebp[0x0022f768][4](W) T0

You can take a look at full file here: http://s000.tinyupload.com/index.php?file_id=03672391815896872254

1

The address called in each call is the beginning of a function (the function's entrypoint).

Each ret address is an end address for that function (note that a function may have more than one ret).

So for example, in the snippet below, 0x000000007c90e8e6 (or 0x7c90e8e6) is the beginning of a function, and 0x7c90e8f6 is the address of the last instruction in that function. (Though again, there could be more than one ret instruction in that function.)

7c9102fe:   call   0x000000007c90e8e6   J@0x00000000[0xffffe5e8][4](R)  T0  M@0x0022f748[0x7c9102c5][4](W)  T0
7c90e8e6:   mov    -0x10(%ebp),%ecx M@0x0022f764[0x0022f834][4](R)  T0  R@ecx[0x7c800000][4](W) T0
7c90e8e9:   mov    %ecx,%fs:0x0 R@ecx[0x0022f834][4](R) T0  M@0x7ffdf000[0x0022f764][4](W)  T0
7c90e8f0:   pop    %ecx M@0x0022f748[0x7c910303][4](R)  T0  R@ecx[0x0022f834][4](W) T0
7c90e8f1:   pop    %edi M@0x0022f74c[0x00000000][4](R)  T0  R@edi[0x00000000][4](W) T0
7c90e8f2:   pop    %esi M@0x0022f750[0x00000000][4](R)  T0  R@esi[0x00000000][4](W) T0
7c90e8f3:   pop    %ebx M@0x0022f754[0x00000000][4](R)  T0  R@ebx[0x00000000][4](W) T0
7c90e8f4:   leave   M@0x0022f774[0x0022f844][4](R)  T0  R@esp[0x0022f758][4](RW)    T0  R@ebp[0x0022f774][4](RW)    T0
7c90e8f5:   push   %ecx R@ecx[0x7c910303][4](R) T0  M@0x0022f774[0x0022f844][4](W)  T0
7c90e8f6:   ret     M@0x0022f774[0x7c910303][4](R)  T0
| improve this answer | |
  • Thank for your answer Jason. So if we have function call inside the function how can I distinguish that it is the function call to an address not start of function call? how can I understand there is more than ret for a function? – user2942756 Jun 17 '15 at 15:07
  • 1
    calls will likely always be to beginnings of functions, not to addresses "in-the-middle" of functions. As for determining if there is more than one ret per function, if you only have the trace and not the original binary, you'd need to keep track of how many rets you see from each function you extract from the trace. – Jason Geffner Jun 17 '15 at 15:56

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