July 2004 - Darwin-kernel - lists.apple.com

Re: Kernel Space, how much?
by Matt Jaffa 07 Jul '04

07 Jul '04

hmmmm, Can I use the libkern classes, OSDictionary, OSArray, OSString, etc. And when I use these kernel classes do they allocate space on the heap and not the stack, so that it wont matter how much I use? Matt On Jul 6, 2004, at 5:08 PM, Godfrey van der Linden wrote: G'day Matt, Interesting problems. Do you yet know how much data we are talking about? Do you have a helper app out in user land? If the amount of data required is large you could try setting up a block of pageable memory inside the kernel. I believe the IOBufferMemoryDescriptor has a pageable option. This may be a good solution for your problem. Remember thought that you will need to be careful with paging the memory in. I haven't looked at the use of pageable memory in detail yet so I can't really tell you how difficult it is to use. I do know that it is possible. Godfrey On Jul 6, , at 15:05, Matt Jaffa wrote: Hi, I am in the process of making a design descision and need to know some things before I finish up. I have a socket filter and want to cache some of the results of my querying, in the socket filter I could malloc some space and store the results in the kernel space, but is this a bad design, is it going to run out of memory, Or I could communicate to userland and store the results in some sort of cache file, but then I have to go to user space everytime my socket filter needs to check the cache? Any suggestions in my approach. Matt Jaffa _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored. _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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Re: Kernel Space, how much?
by Godfrey van der Linden 06 Jul '04

06 Jul '04

G'day Matt, Interesting problems. Do you yet know how much data we are talking about? Do you have a helper app out in user land? If the amount of data required is large you could try setting up a block of pageable memory inside the kernel. I believe the IOBufferMemoryDescriptor has a pageable option. This may be a good solution for your problem. Remember thought that you will need to be careful with paging the memory in. I haven't looked at the use of pageable memory in detail yet so I can't really tell you how difficult it is to use. I do know that it is possible. Godfrey On Jul 6, , at 15:05, Matt Jaffa wrote: Hi, I am in the process of making a design descision and need to know some things before I finish up. I have a socket filter and want to cache some of the results of my querying, in the socket filter I could malloc some space and store the results in the kernel space, but is this a bad design, is it going to run out of memory, Or I could communicate to userland and store the results in some sort of cache file, but then I have to go to user space everytime my socket filter needs to check the cache? Any suggestions in my approach. Matt Jaffa _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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reproducible bug in OSX's syslogd when REMOTE LOGGING
by OpenMacNews 06 Jul '04

06 Jul '04

hi all, i think this is the right place for this .... i've enabled REMOTE syslogging in OSX 10.3.4 by changing ~line_no:11 in /etc/rc from: /usr/sbin/syslogd -s -m 0 -u to /usr/sbin/syslogd -m 0 -u with this change, remote logging works fine. BUT, it leaves the syslog open to UDP traffic from ALL ips . so in trying to limit logging access to ONLY specific IP, i note: usage: syslogd [-46Acdknosuv] [-a allowed_peer] [-b bind address] [-f config_file] [-l log_socket] [-m mark_interval] [-P pid_file] [-p log_socket] PROBLEM #1: checking the apple manpage for syslogd, there's no mention of the "-a allowed_per" flag. which MAY be cuz its old/not updated: HISTORY The syslogd command appeared in 4.3BSD. 4.2 Berkeley Distribution June 6, 1993 4.2 Berkeley Distribution so, jumping over to the FreeBSD manpages, i learn that: -a allowed_peer Allow allowed_peer to log to this syslogd using UDP datagrams. Multiple -a options may be specified. Allowed_peer can be any of the following: ipaddr/masklen[:service] Accept datagrams from ipaddr (in the usual dotted quad notation) with masklen bits being taken into account when doing the address comparison. ipaddr can be also IPv6 address by enclosing the address with `[' and `]'. If specified, service is the name or number of an UDP service (see services(5)) the source packet must belong to. A service of `*' allows packets being sent from any UDP port. The default service is `syslog'. If ipaddr is IPv4 address, a missing masklen will be substituted by the historic class A or class B netmasks if ipaddr belongs into the address range of class A or B, respectively, or by 24 otherwise. If ipaddr is IPv6 address, a missing masklen will be substituted by 128. domainname[:service] Accept datagrams where the reverse address lookup yields domainname for the sender address. The meaning of service is as explained above. *domainname[:service] Same as before, except that any source host whose name ends in domainname will get permission. The -a options are ignored if the -s option is also specified. seems to be exactly what i want/need. if i spec'y a SINGLE, FIXED source_port, e.g.: /usr/sbin/syslogd -a 172.30.11.101/32:2048 -m 0 -u remote logging WORKS. however, since my remote box uses variable src ports, and there's no way to specify a fixed port, i need to use the "*" port wildcard. unfortunately, PROBLEM #2: it chokes with "no match", not accepting the cmd/launch /usr/sbin/syslogd -a 172.30.11.101/32:* -m 0 -u su: /usr/sbin/syslogd: No match. on a whim, escaping or quoting the * with either: /usr/sbin/syslogd -a 172.30.11.101/32:\* -m 0 -u or /usr/sbin/syslogd -a 172.30.11.101/32:"*" -m 0 -u gets the command accepted, and syslog launches, but it doesn't get any remote log entries. returning to a specific port spec: /usr/sbin/syslogd -a 172.30.11.101/32:2048 -m 0 -u and remote logging works again as expected, as long as the src port used remains (here) 2048 BOTTOM LINE: (1) manpage for OSX's syslogd is out of synch with its available options (2) the manpage implies that it's BSD's syslogd, but the BSD-specified "*" port wildcard is not supported. is this known? is there a workaround? richard _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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Re: Restrictions in kexts
by Justin Walker 06 Jul '04

06 Jul '04

On Jul 6, 2004, at 14:04, Krishna Monian wrote: I am loggin file accesses in certain directories, and passing this on to the user and the user needs the complete path. However, when system calls are made at the terminal only relative paths are used. It would be nice if there was a way to reconstruct the whole path in the kext and pass it on to the user. There *really* is no good way to do that, and if there were, I would argue against doing it in the kernel. At best, you could try to do the (re)construction of the "full path" in user mode. The problem is that "path name" is a unix abstraction, and is not necessarily a file-system concept. In addition, there may not be a well-defined "full path" to a file (think links, hard and symbolic). Regards, Justin -- Justin C. Walker, Curmudgeon-At-Large * Institute for General Semantics | It's not whether you win or lose... | It's whether *I* win or lose. *--------------------------------------*-------------------------------* _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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Kernel Space, how much?
by Matt Jaffa 06 Jul '04

06 Jul '04

Hi, I am in the process of making a design descision and need to know some things before I finish up. I have a socket filter and want to cache some of the results of my querying, in the socket filter I could malloc some space and store the results in the kernel space, but is this a bad design, is it going to run out of memory, Or I could communicate to userland and store the results in some sort of cache file, but then I have to go to user space everytime my socket filter needs to check the cache? Any suggestions in my approach. Matt Jaffa _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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Re: Restrictions in kexts
by Krishna Monian 06 Jul '04

06 Jul '04

I am loggin file accesses in certain directories, and passing this on to the user and the user needs the complete path. However, when system calls are made at the terminal only relative paths are used. It would be nice if there was a way to reconstruct the whole path in the kext and pass it on to the user. --- Justin Walker <justin(a)mac.com> wrote: > > On Jul 6, 2004, at 13:54, Krishna Monian wrote: > > > Is there some other equivalent method of doing > what > > the 3 functions do in a kext? > > I suspect not. Why do you want to do that? > > -- > Justin C. Walker, Curmudgeon-At-Large * > Institute for General Semantics | "Weaseling > out of things is > what > | separates > us from the animals. > | Well, > except the weasel." > | - > Homer J Simpson > *--------------------------------------*-------------------------------* > > __________________________________ Do you Yahoo!? Yahoo! Mail Address AutoComplete - You start. We finish. http://promotions.yahoo.com/new_mail _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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Re: Restrictions in kexts
by Brian Bergstrand 06 Jul '04

06 Jul '04

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Jul 6, 2004, at 3:25 PM, Krishna Monian wrote: > Hi, > Is there some sort of restriction on using the > following functions in a kext? > > FSMakeFSSPec > FSpMakeFSRef > FSRefMakePath > Yes, most definitely there is a restriction. You may not use any user land Frameworks or Libs in the kernel. And these symbols come from the Carbon Framework. If you are trying to get a full path in the kernel, you may as well give up now. It is pretty much impossible currently. Brian Bergstrand <http://www.bergstrand.org/brian/>, AIM: triryche206 PGP Key: <http://www.bergstrand.org/brian/misc/public_key.txt> I respect faith, but doubt is what gets you an education. - Wilson Mizner As of 03:53:17 PM, iTunes is playing "Heaven's Trail (No Way Out)" from "The Great Radio Controversy" by "Tesla" -----BEGIN PGP SIGNATURE----- Version: PGP 8.1 iQA/AwUBQOsEHHnR2Fu2x7aiEQKjuQCeMoYSzRNatoNimIjgLlkxt+ZqT3oAn18e Ys+5qAh96kuvVvb1ZIomgGTY =VQzl -----END PGP SIGNATURE----- _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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Re: Restrictions in kexts
by Justin Walker 06 Jul '04

06 Jul '04

On Jul 6, 2004, at 13:54, Krishna Monian wrote: Is there some other equivalent method of doing what the 3 functions do in a kext? I suspect not. Why do you want to do that? -- Justin C. Walker, Curmudgeon-At-Large * Institute for General Semantics | "Weaseling out of things is what | separates us from the animals. | Well, except the weasel." | - Homer J Simpson *--------------------------------------*-------------------------------* _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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Re: Restrictions in kexts
by Krishna Monian 06 Jul '04

06 Jul '04

Is there some other equivalent method of doing what the 3 functions do in a kext? Thanks Krishna --- Justin Walker <justin(a)mac.com> wrote: > > On Jul 6, 2004, at 13:25, Krishna Monian wrote: > > > Hi, > > Is there some sort of restriction on using the > > following functions in a kext? > > > > FSMakeFSSPec > > FSpMakeFSRef > > FSRefMakePath > > You betcha. Haven't you read the docs on kexts? > > You can not use *any* user-mode libraries, and you > can't use *any* > frameworks, in a kext (the Kernel.framework is a > framework in name > only; it provides no code). > > Regards, > > Justin > > -- > Justin C. Walker, Curmudgeon-At-Large * > Institute for General Semantics | Some people > have a mental > | horizon > of radius zero, and > | call it > their point of view. > | -- > David Hilbert > *--------------------------------------*-------------------------------* > > __________________________________ Do you Yahoo!? Yahoo! Mail - 50x more storage than other providers! http://promotions.yahoo.com/new_mail _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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Re: Restrictions in kexts
by Justin Walker 06 Jul '04

06 Jul '04

On Jul 6, 2004, at 13:25, Krishna Monian wrote: Hi, Is there some sort of restriction on using the following functions in a kext? FSMakeFSSPec FSpMakeFSRef FSRefMakePath You betcha. Haven't you read the docs on kexts? You can not use *any* user-mode libraries, and you can't use *any* frameworks, in a kext (the Kernel.framework is a framework in name only; it provides no code). Regards, Justin -- Justin C. Walker, Curmudgeon-At-Large * Institute for General Semantics | Some people have a mental | horizon of radius zero, and | call it their point of view. | -- David Hilbert *--------------------------------------*-------------------------------* _______________________________________________ darwin-kernel mailing list | darwin-kernel(a)lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.

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