021869b542
8 Commits
Author | SHA1 | Message | Date | |
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Bill Paul
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d02239a3af |
Create new i386 windows/bsd thunking layer, similar to the amd64 thunking
layer, but with a twist. The twist has to do with the fact that Microsoft supports structured exception handling in kernel mode. On the i386 arch, exception handling is implemented by hanging an exception registration list off the Thread Environment Block (TEB), and the TEB is accessed via the %fs register. The problem is, we use %fs as a pointer to the pcpu stucture, which means any driver that tries to write through %fs:0 will overwrite the curthread pointer and make a serious mess of things. To get around this, Project Evil now creates a special entry in the GDT on each processor. When we call into Windows code, a context switch routine will fix up %fs so it points to our new descriptor, which in turn points to a fake TEB. When the Windows code returns, or calls out to an external routine, we swap %fs back again. Currently, Project Evil makes use of GDT slot 7, which is all 0s by default. I fully expect someone to jump up and say I can't do that, but I couldn't find any code that makes use of this entry anywhere. Sadly, this was the only method I could come up with that worked on both UP and SMP. (Modifying the LDT works on UP, but becomes incredibly complicated on SMP.) If necessary, the context switching stuff can be yanked out while preserving the convention calling wrappers. (Fortunately, it looks like Microsoft uses some special epilog/prolog code on amd64 to implement exception handling, so the same nastiness won't be necessary on that arch.) The advantages are: - Any driver that uses %fs as though it were a TEB pointer won't clobber pcpu. - All the __stdcall/__fastcall/__regparm stuff that's specific to gcc goes away. Also, while I'm here, switch NdisGetSystemUpTime() back to using nanouptime() again. It turns out nanouptime() is way more accurate than just using ticks(). On slower machines, the Atheros drivers I tested seem to take a long time to associate due to the loss in accuracy. |
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Bill Paul
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d8f2dda739 |
Add support for Windows/x86-64 binaries to Project Evil.
Ville-Pertti Keinonen (will at exomi dot comohmygodnospampleasekthx) deserves a big thanks for submitting initial patches to make it work. I have mangled his contributions appropriately. The main gotcha with Windows/x86-64 is that Microsoft uses a different calling convention than everyone else. The standard ABI requires using 6 registers for argument passing, with other arguments on the stack. Microsoft uses only 4 registers, and requires the caller to leave room on the stack for the register arguments incase the callee needs to spill them. Unlike x86, where Microsoft uses a mix of _cdecl, _stdcall and _fastcall, all routines on Windows/x86-64 uses the same convention. This unfortunately means that all the functions we export to the driver require an intermediate translation wrapper. Similarly, we have to wrap all calls back into the driver binary itself. The original patches provided macros to wrap every single routine at compile time, providing a secondary jump table with a customized wrapper for each exported routine. I decided to use a different approach: the call wrapper for each function is created from a template at runtime, and the routine to jump to is patched into the wrapper as it is created. The subr_pe module has been modified to patch in the wrapped function instead of the original. (On x86, the wrapping routine is a no-op.) There are some minor API differences that had to be accounted for: - KeAcquireSpinLock() is a real function on amd64, not a macro wrapper around KfAcquireSpinLock() - NdisFreeBuffer() is actually IoFreeMdl(). I had to change the whole NDIS_BUFFER API a bit to accomodate this. Bugs fixed along the way: - IoAllocateMdl() always returned NULL - kern_windrv.c:windrv_unload() wasn't releasing private driver object extensions correctly (found thanks to memguard) This has only been tested with the driver for the Broadcom 802.11g chipset, which was the only Windows/x86-64 driver I could find. |
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Bill Paul
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df7b7cf4c3 |
Begin the first phase of trying to add IRP support (and ultimately
USB device support): - Convert all of my locally chosen function names to their actual Windows equivalents, where applicable. This is a big no-op change since it doesn't affect functionality, but it helps avoid a bit of confusion (it's now a lot easier to see which functions are emulated Windows API routines and which are just locally defined). - Turn ndis_buffer into an mdl, like it should have been. The structure is the same, but now it belongs to the subr_ntoskrnl module. - Implement a bunch of MDL handling macros from Windows and use them where applicable. - Correct the implementation of IoFreeMdl(). - Properly implement IoAllocateMdl() and MmBuildMdlForNonPagedPool(). - Add the definitions for struct irp and struct driver_object. - Add IMPORT_FUNC() and IMPORT_FUNC_MAP() macros to make formatting the module function tables a little cleaner. (Should also help with AMD64 support later on.) - Fix if_ndis.c to use KeRaiseIrql() and KeLowerIrql() instead of the previous calls to hal_raise_irql() and hal_lower_irql() which have been renamed. The function renaming generated a lot of churn here, but there should be very little operational effect. |
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Warner Losh
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898b0535b7 | Start each of the license/copyright comments with /*- | ||
Bill Paul
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f13b900a9e |
Big mess 'o changes:
- Give ndiscvt(8) the ability to process a .SYS file directly into a .o file so that we don't have to emit big messy char arrays into the ndis_driver_data.h file. This behavior is currently optional, but may become the default some day. - Give ndiscvt(8) the ability to turn arbitrary files into .ko files so that they can be pre-loaded or kldloaded. (Both this and the previous change involve using objcopy(1)). - Give NdisOpenFile() the ability to 'read' files out of kernel memory that have been kldloaded or pre-loaded, and disallow the use of the normal vn_open() file opening method during bootstrap (when no filesystems have been mounted yet). Some people have reported that kldloading if_ndis.ko works fine when the system is running multiuser but causes a panic when the modile is pre-loaded by /boot/loader. This happens with drivers that need to use NdisOpenFile() to access external files (i.e. firmware images). NdisOpenFile() won't work during kernel bootstrapping because no filesystems have been mounted. To get around this, you can now do the following: o Say you have a firmware file called firmware.img o Do: ndiscvt -f firmware.img -- this creates firmware.img.ko o Put the firmware.img.ko in /boot/kernel o add firmware.img_load="YES" in /boot/loader.conf o add if_ndis_load="YES" and ndis_load="YES" as well Now the loader will suck the additional file into memory as a .ko. The phony .ko has two symbols in it: filename_start and filename_end, which are generated by objcopy(1). ndis_open_file() will traverse each module in the module list looking for these symbols and, if it finds them, it'll use them to generate the file mapping address and length values that the caller of NdisOpenFile() wants. As a bonus, this will even work if the file has been statically linked into the kernel itself, since the "kernel" module is searched too. (ndiscvt(8) will generate both filename.o and filename.ko for you). - Modify the mechanism used to provide make-pretend FASTCALL support. Rather than using inline assembly to yank the first two arguments out of %ecx and %edx, we now use the __regparm__(3) attribute (and the __stdcall__ attribute) and use some macro magic to re-order the arguments and provide dummy arguments as needed so that the arguments passed in registers end up in the right place. Change taken from DragonflyBSD version of the NDISulator. |
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Bill Paul
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2b94c69d1d |
Continue my efforts to imitate Windows as closely as possible by
attempting to duplicate Windows spinlocks. Windows spinlocks differ from FreeBSD spinlocks in the way they block preemption. FreeBSD spinlocks use critical_enter(), which masks off _all_ interrupts. This prevents any other threads from being scheduled, but it also prevents ISRs from running. In Windows, preemption is achieved by raising the processor IRQL to DISPATCH_LEVEL, which prevents other threads from preempting you, but does _not_ prevent device ISRs from running. (This is essentially what Solaris calls dispatcher locks.) The Windows spinlock itself (kspin_lock) is just an integer value which is atomically set when you acquire the lock and atomically cleared when you release it. FreeBSD doesn't have IRQ levels, so we have to cheat a little by using thread priorities: normal thread priority is PASSIVE_LEVEL, lowest interrupt thread priority is DISPATCH_LEVEL, highest thread priority is DEVICE_LEVEL (PI_REALTIME) and critical_enter() is HIGH_LEVEL. In practice, only PASSIVE_LEVEL and DISPATCH_LEVEL matter to us. The immediate benefit of all this is that I no longer have to rely on a mutex pool. Now, I'm sure many people will be seized by the urge to criticize me for doing an end run around our own spinlock implementation, but it makes more sense to do it this way. Well, it does to me anyway. Overview of the changes: - Properly implement hal_lock(), hal_unlock(), hal_irql(), hal_raise_irql() and hal_lower_irql() so that they more closely resemble their Windows counterparts. The IRQL is determined by thread priority. - Make ntoskrnl_lock_dpc() and ntoskrnl_unlock_dpc() do what they do in Windows, which is to atomically set/clear the lock value. These routines are designed to be called from DISPATCH_LEVEL, and are actually half of the work involved in acquiring/releasing spinlocks. - Add FASTCALL1(), FASTCALL2() and FASTCALL3() macros/wrappers that allow us to call a _fastcall function in spite of the fact that our version of gcc doesn't support __attribute__((__fastcall__)) yet. The macros take 1, 2 or 3 arguments, respectively. We need to call hal_lock(), hal_unlock() etc... ourselves, but can't really invoke the function directly. I could have just made the underlying functions native routines and put _fastcall wrappers around them for the benefit of Windows binaries, but that would create needless bloat. - Remove ndis_mtxpool and all references to it. We don't need it anymore. - Re-implement the NdisSpinLock routines so that they use hal_lock() and friends like they do in Windows. - Use the new spinlock methods for handling lookaside lists and linked list updates in place of the mutex locks that were there before. - Remove mutex locking from ndis_isr() and ndis_intrhand() since they're already called with ndis_intrmtx held in if_ndis.c. - Put ndis_destroy_lock() code under explicit #ifdef notdef/#endif. It turns out there are some drivers which stupidly free the memory in which their spinlocks reside before calling ndis_destroy_lock() on them (touch-after-free bug). The ADMtek wireless driver is guilty of this faux pas. (Why this doesn't clobber Windows I have no idea.) - Make NdisDprAcquireSpinLock() and NdisDprReleaseSpinLock() into real functions instead of aliasing them to NdisAcaquireSpinLock() and NdisReleaseSpinLock(). The Dpr routines use KeAcquireSpinLockAtDpcLevel() level and KeReleaseSpinLockFromDpcLevel(), which acquires the lock without twiddling the IRQL. - In ndis_linksts_done(), do _not_ call ndis_80211_getstate(). Some drivers may call the status/status done callbacks as the result of setting an OID: ndis_80211_getstate() gets OIDs, which means we might cause the driver to recursively access some of its internal structures unexpectedly. The ndis_ticktask() routine will call ndis_80211_getstate() for us eventually anyway. - Fix the channel setting code a little in ndis_80211_setstate(), and initialize the channel to IEEE80211_CHAN_ANYC. (The Microsoft spec says you're not supposed to twiddle the channel in BSS mode; I may need to enforce this later.) This fixes the problems I was having with the ADMtek adm8211 driver: we were setting the channel to a non-standard default, which would cause it to fail to associate in BSS mode. - Use hal_raise_irql() to raise our IRQL to DISPATCH_LEVEL when calling certain miniport routines, per the Microsoft documentation. I think that's everything. Hopefully, other than fixing the ADMtek driver, there should be no apparent change in behavior. |
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Bill Paul
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ece759a4da |
The definition for __stdcall logically belongs in pe_var.h, but
the definitions for NDIS_BUS_SPACE_IO and NDIS_BUS_SPACE_MEM logically belong in hal_var.h. At least, that's my story, and I'm sticking to it. Also, remove definition of __stdcall from if_ndis.c now that it's pulled in from pe_var.h. |
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Bill Paul
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c854fc1092 |
Commit the first cut of Project Evil, also known as the NDISulator.
Yes, it's what you think it is. Yes, you should run away now. This is a special compatibility module for allowing Windows NDIS miniport network drivers to be used with FreeBSD/x86. This provides _binary_ NDIS compatibility (not source): you can run NDIS driver code, but you can't build it. There are three main parts: sys/compat/ndis: the NDIS compat API, which provides binary compatibility functions for many routines in NDIS.SYS, HAL.dll and ntoskrnl.exe in Windows (these are the three modules that most NDIS miniport drivers use). The compat module also contains a small PE relocator/dynalinker which relocates the Windows .SYS image and then patches in our native routines. sys/dev/if_ndis: the if_ndis driver wrapper. This module makes use of the ndis compat API and can be compiled with a specially prepared binary image file (ndis_driver_data.h) containing the Windows .SYS image and registry key information parsed out of the accompanying .INF file. Once if_ndis.ko is built, it can be loaded and unloaded just like a native FreeBSD kenrel module. usr.sbin/ndiscvt: a special utility that converts foo.sys and foo.inf into an ndis_driver_data.h file that can be compiled into if_ndis.o. Contains an .inf file parser graciously provided by Matt Dodd (and mercilessly hacked upon by me) that strips out device ID info and registry key info from a .INF file and packages it up with a binary image array. The ndiscvt(8) utility also does some manipulation of the segments within the .sys file to make life easier for the kernel loader. (Doing the manipulation here saves the kernel code from having to move things around later, which would waste memory.) ndiscvt is only built for the i386 arch. Only files.i386 has been updated, and none of this is turned on in GENERIC. It should probably work on pc98. I have no idea about amd64 or ia64 at this point. This is still a work in progress. I estimate it's about %85 done, but I want it under CVS control so I can track subsequent changes. It has been tested with exactly three drivers: the LinkSys LNE100TX v4 driver (Lne100v4.sys), the sample Intel 82559 driver from the Windows DDK (e100bex.sys) and the Broadcom BCM43xx wireless driver (bcmwl5.sys). It still needs to have a net80211 stuff added to it. To use it, you would do something like this: # cd /sys/modules/ndis # make; make load # cd /sys/modules/if_ndis # ndiscvt -i /path/to/foo.inf -s /path/to/foo.sys -o ndis_driver_data.h # make; make load # sysctl -a | grep ndis All registry keys are mapped to sysctl nodes. Sometimes drivers refer to registry keys that aren't mentioned in foo.inf. If this happens, the NDIS API module creates sysctl nodes for these keys on the fly so you can tweak them. An example usage of the Broadcom wireless driver would be: # sysctl hw.ndis0.EnableAutoConnect=1 # sysctl hw.ndis0.SSID="MY_SSID" # sysctl hw.ndis0.NetworkType=0 (0 for bss, 1 for adhoc) # ifconfig ndis0 <my ipaddr> netmask 0xffffff00 up Things to be done: - get rid of debug messages - add in ndis80211 support - defer transmissions until after a status update with NDIS_STATUS_CONNECTED occurs - Create smarter lookaside list support - Split off if_ndis_pci.c and if_ndis_pccard.c attachments - Make sure PCMCIA support works - Fix ndiscvt to properly parse PCMCIA device IDs from INF files - write ndisapi.9 man page |