Hi, all.
i want to modify the original user-data contained irp from I/O manager. (active filter)
but, how can i determine the valid buffer among the SystemBuffer, MdlAddress, UserBuffer.
if i take one - that is a NOT NULL buffer, in these buffers - but, i can’t assume the validation of the buffer.
Can any one of you tell me how to use the original users buffer to modify it.
and what is the difference between passive and active filter.
Thanks in advance,
choosen-park.
thanks Dan.
(but i can’t access the web site. i don’t know exactly. … network traffic or etc. i’m accessing…)
Anyway, i think the core difference of active and passive filter is the position of layered chain.
active is the highest component in layer chain, so the driver can access user-space address directly.
am i wrong? then tell me the trueth please. and if i’m right, i want to know how to place my filter to highest position of that.
very thanks in advance.
choosen-park.
----- Original Message -----
From: Dan Partelly
To: File Systems Developers
Sent: Friday, June 21, 2002 9:42 PM
Subject: [ntfsd] Re: modify the original user-data
Check this
http://www.osr.com/resources_ifsfaq.shtml#Q56
You are currently subscribed to ntfsd as: xxxxx@jlandsoft.com
To unsubscribe send a blank email to xxxxx@lists.osr.com
Park,
Your wrong. Any filter can be active or passive, regardless of the position in the device stack. “Passive” filter here is used mostly
for filters who mainly examine data, and pass the request whithout any other operations to the next device on stack. For example, a FS activity logger is passive. Active filters are those which activly modify the data before passsing the IRP down, or they choose
to complete the operation themselves. For example , a FS filter which hides directoryes or files. I think you got the ideea.
Best Regards, Dan
----- Original Message -----
From: choosen-park
To: File Systems Developers
Sent: Friday, June 21, 2002 4:18 PM
Subject: [ntfsd] Re: modify the original user-data
thanks Dan.
(but i can’t access the web site. i don’t know exactly. … network traffic or etc. i’m accessing…)
Anyway, i think the core difference of active and passive filter is the position of layered chain.
active is the highest component in layer chain, so the driver can access user-space address directly.
am i wrong? then tell me the trueth please. and if i’m right, i want to know how to place my filter to highest position of that.
very thanks in advance.
choosen-park.
----- Original Message -----
From: Dan Partelly
To: File Systems Developers
Sent: Friday, June 21, 2002 9:42 PM
Subject: [ntfsd] Re: modify the original user-data
Check this
http://www.osr.com/resources_ifsfaq.shtml#Q56
You are currently subscribed to ntfsd as: xxxxx@jlandsoft.com
To unsubscribe send a blank email to %%email.unsub%%
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Ok. Dan.
thank you for give a right concept to me.
but, i don’t know how can i determine the right buffer among buffers of a given IRP yet.
i think the checking that what is the not null buffer is not answer of this.
because , inspite of UserBuffer is not null, it is possible that the buffer is user-space address, i guess.
actually, i have wonder that how can i change my passive filter to active?
(how can access the origin user-data)
please give me a key hint or great advise for this.
Sincerely, thanks.
----- Original Message -----
From: Dan Partelly
To: File Systems Developers
Sent: Friday, June 21, 2002 10:42 PM
Subject: [ntfsd] Re: modify the original user-data
Park,
Your wrong. Any filter can be active or passive, regardless of the position in the device stack. “Passive” filter here is used mostly
for filters who mainly examine data, and pass the request whithout any other operations to the next device on stack. For example, a FS activity logger is passive. Active filters are those which activly modify the data before passsing the IRP down, or they choose
to complete the operation themselves. For example , a FS filter which hides directoryes or files. I think you got the ideea.
Best Regards, Dan
----- Original Message -----
From: choosen-park
To: File Systems Developers
Sent: Friday, June 21, 2002 4:18 PM
Subject: [ntfsd] Re: modify the original user-data
thanks Dan.
(but i can’t access the web site. i don’t know exactly. … network traffic or etc. i’m accessing…)
Anyway, i think the core difference of active and passive filter is the position of layered chain.
active is the highest component in layer chain, so the driver can access user-space address directly.
am i wrong? then tell me the trueth please. and if i’m right, i want to know how to place my filter to highest position of that.
very thanks in advance.
choosen-park.
----- Original Message -----
From: Dan Partelly
To: File Systems Developers
Sent: Friday, June 21, 2002 9:42 PM
Subject: [ntfsd] Re: modify the original user-data
Check this
Although that link doesn’t work right now, this one does:
http://ftp.osr.com/resources_ifsfaq.shtml#Q56
-----Original Message-----
From: Dan Partelly [mailto:xxxxx@rdsor.ro]
Sent: Friday, June 21, 2002 7:42 AM
To: File Systems Developers
Subject: [ntfsd] Re: modify the original user-data
Check this
http://www.osr.com/resources_ifsfaq.shtml#Q56
You are currently subscribed to ntfsd as: xxxxx@inin.com
To unsubscribe send a blank email to %%email.unsub%%
thank you, Fuller.
Best Regards, park.
----- Original Message -----
From: Fuller, Rob
To: File Systems Developers
Sent: Friday, June 21, 2002 11:23 PM
Subject: [ntfsd] Re: modify the original user-data
Although that link doesn’t work right now, this one does:
http://ftp.osr.com/resources_ifsfaq.shtml#Q56
-----Original Message-----
From: Dan Partelly [mailto:xxxxx@rdsor.ro]
Sent: Friday, June 21, 2002 7:42 AM
To: File Systems Developers
Subject: [ntfsd] Re: modify the original user-data
Check this
http://www.osr.com/resources_ifsfaq.shtml#Q56
You are currently subscribed to ntfsd as: xxxxx@jlandsoft.com
To unsubscribe send a blank email to xxxxx@lists.osr.com