Use the application layer's space directly on the drive layer

</pre><p> Requirements: The application layer requests a space and then passes the address to the drive layer, which drives the processed data directly into the space specified by the application layer, similar to the Copy_from_user under Linux. </p><p></p><p> Application Layer Code snippet: </p><p><span style= "White-space:pre" > Pass the requested address to the drive layer </span></p><pre code_snippet_id= "576642" snippet_file_name= "blog_20150110_2_1402064" Name= "code" class= "CPP" >        CHAR    buf[64] = {0};int Iwritelen = 0;char *pwaddr = Null;char *praddr = null;unsigned Long *ptmp = Null;pwaddr = (char*) calloc (1, +);p raddr = (char*) calloc (1, +); if (pwaddr ==null) | | (Praddr==null)) {Puts ("Calloc error"); CloseHandle (hdevice); return 0;}  memset (pwaddr, ' A ', ');p tmp = (unsigned long*) buf;ptmp[0] = (unsigned long) 0;//pwaddr;ptmp[1] = (unsigned long) praddr;if (WriteFile (Hdevice, buf, 8, (Lpdword) &iwritelen, NULL)) {puts ("write Success");} Else{puts ("Write Failed");}

Driver Layer Code snippet:

VOID uaddr2daddr (PVOID pusr, unsigned long iusrlen, BOOLEAN bRead) {int i = 0; Lock_operation opt = iowriteaccess; Puchar pvir = NULL; PMDL MDL, if (! Mmisaddressvalid (PUSR))//If there is no such judgment, the application is an illegal address, will result in the following virtual address, blue screen {kdprint (("Mmisaddressvalid univalid error\n"); return;} MDL = IOALLOCATEMDL (pusr, Iusrlen, FALSE, TRUE, NULL); if (mdl = = NULL) {Kdprint (("Ioallocatemdl error\n"); return;} if (bRead) {opt = ioreadaccess;} Mmprobeandlockpages (MDL, UserMode, opt);p vir = Mmmaplockedpagesspecifycache (Mdl,kernelmode,mmcached,null,false, normalpagepriority)///If Puser is not valid, calling this function causes a blue screen kdprint ("Mmmaplockedpagesspecifycache:% #x \ n", (unsigned long) pvir)) ;p vir = Mmgetsystemaddressformdlsafe (MDL, normalpagepriority); <span style= "font-family:arial, Helvetica, Sans-serif; " >//if Puser is not valid, calling this function causes a blue screen </span>kdprint ("Mmgetsystemaddressformdlsafe:% #x \ n", (unsigned long) pvir)); Pvir = mmgetmdlvirtualaddress (MDL); <span style= "font-family:arial, Helvetica, Sans-serif;" >//if Puser is illegal, calling this function causes a blue screen </span&Gt Kdprint ("mmgetmdlvirtualaddress:% #x \ n", (unsigned long) pvir)), if (pvir = = NULL) {Kdprint (("Ioallocatemdl error\n")); return;} Kdprint ("\ n----------------------DML Data------------------\ n \ nthe")), if (BRead) {for (i=0, i<4; i++) {for (i=0; i< 4; i++) {Pvir[i] = ' B ';}}} Else{for (i=0; i<4; i++) {Kdprint (("%c", Pvir[i]);}} Kdprint ("\ n-------------------End DML Data------------------\ n \ nthe")); Mmunlockpages (MDL); iofreemdl (MDL);}

In the DbgView print driver: The virtual address values obtained by the 3 functions are as follows:

Mmmaplockedpagesspecifycache:0xae44b3b0
Mmgetsystemaddressformdlsafe:0xae44b3b0
Mmgetmdlvirtualaddress:0x7013b0

All of the above three functions can be completed with requirements.

Code Download:

Use the application layer's space directly on the drive layer