From: Digestifier To: Linux-Admin@senator-bedfellow.mit.edu Reply-To: Linux-Admin@senator-bedfellow.mit.edu Date: Sun, 31 Oct 93 17:16:01 EST Subject: Linux-Admin Digest #133 Linux-Admin Digest #133, Volume #1 Sun, 31 Oct 93 17:16:01 EST Contents: Linux HOWTO Index (Matt Welsh) Corel SCSI LS2000 card [Q] (Claus S. Kristensen) Re: BIG Security Hole in SLACKWARE (jacobsd@solar.cor2.epa.gov) Re: BIG Security Hole in SLACKWARE (Jean Liddle) Re: Introduction into Unix (Robert L. McMillin) Re: Is PLIP possible form a LAN? (Daniel D Deavours) ---------------------------------------------------------------------------- From: mdw@sunsite.unc.edu (Matt Welsh) Crossposted-To: comp.os.linux.announce,comp.os.linux.help,news.answers,comp.answers Subject: Linux HOWTO Index Date: 31 Oct 1993 16:36:17 GMT Archive-name: linux/howto/index Last-modified: 31 October 1993 The Linux HOWTO Index Matt Welsh, ============================================================================= Last Modified 31 October 1993 This is an introduction and index to the Linux HOWTO documents. 0. What are Linux HOWTOs? Linux HOWTOs are short online documents which describe in detail a certain aspect of configuring or using the Linux system. For example, there is the Installation HOWTO, which gives instructions on installing Linux, and the Mail HOWTO, which describes how to set up and configure mail under Linux. Other examples include the NET-2-HOWTO (previously the NET-2-FAQ) and the Linux-vs-386BSD HOWTO. Information in HOWTOs is generally more detailed and in-depth than what can be squeezed into the Linux FAQ. For this reason, the Linux FAQ is being rewritten. A large amount of the information contained therein will be relegated to various HOWTO documents. The FAQ will be a shorter list of frequently asked questions about Linux, covering small specific topics. Most of the ``useful'' information in the FAQ will now be covered in the HOWTOs. HOWTOs are comprehensive docs---much like an FAQ but generally not in question-and-answer format. However, many HOWTOs contain an FAQ section at the end. For example, the NET-2-FAQ has been renamed to the NET-2-HOWTO, because it wasn't in question-and-answer format. However, you will see the NET-2-HOWTO named as the NET-2-FAQ in many places. The two docs are one and the same. 1. Where to get Linux HOWTOs HOWTOs can be retrieved via anonymous FTP from the following sites: sunsite.unc.edu:/pub/Linux/docs/HOWTO tsx-11.mit.edu:/pub/linux/docs/HOWTO The Index, printed below, lists the currently available HOWTOs. HOWTOs are also posted regularly to the newsgroups comp.os.linux and comp.os.linux.announce. In addition, a number of the HOWTOs will be crossposted to news.answers. Therefore, you can find the Linux HOWTOs on the news.answers archive site rtfm.mit.edu. 2. HOWTO Index The following Linux HOWTOs are currently available. The list is small, because this is a relatively new project. * INSTALLATION HOWTO. How to obtain and install Linux. This is the first document which a Linux newcomer should read. It discusses how to obtain Linux, both from the Internet and via Snail-mail, and how to install it. Focuses primarily on the SLS distribution of Linux, which is the current de facto standard. * Linux INFO-SHEET. A general technical introduction to Linux, listing its features, supported hardware, and other general information. * Linux META-FAQ. A list of sources of information about Linux, such as documentation, newsgroups, FTP sites, and so on. * NET-2 HOWTO. Describes how to install and configure the Linux NET-2 TCP/IP code, in kernels 0.99.pl10 and above. (This has nothing to do with the so-called BSD NET-2 distribution.) Discusses various aspects of TCP/IP networking under Linux, including the use of SLIP. The complete instruction manual for TCP/IP under Linux. * Ethernet HOWTO. A HOWTO about the various Ethernet device drivers which are available for Linux. Should be read along with the NET-2 HOWTO by anyone using Ethernet for TCP/IP on Linux. * XFree86 HOWTO. This HOWTO describes how to install and configure XFree86-2.0 for Linux. Most of this is Linux-specific, and expects you to read the documentation included in the XFree86-2.0 package. * Mail HOWTO. All about configuration of electronic mail with Linux, including UUCP and TCP/IP mailers such as Smail and sendmail. * UUCP HOWTO. How to configure UUCP to transfer files, mail, and news to other UNIX machines on a UUCP-based connection. Includes discussion of Taylor UUCP for Linux. * News HOWTO. Setup and configuration of news software, such as C News, INN, and newsreaders (such as rn and tin) under Linux. * Printing HOWTO. How to configure and use printing software under Linux, such as lp, lpr, etc. including remote printing. * SCSI HOWTO. All about SCSI tapes, drives, and CD-ROMs under Linux. * Hardware Compatibility HOWTO. An extensive list of hardware supported by Linux. WANTED. I would be very happy if someone would write the following HOWTO documents, and submit them to me (see the instructions in the next section below). Most of these are modifications of existing FAQ documents, and should be easy to put into HOWTO format. Keep in mind that HOWTOs generally aren't in FAQ format, but can contain an FAQ section at the end. Some of these are under construction; however, if you're interested in working on one of them, please let me know. * GCC/LIBRARY HOWTO. Discussing installation/upgrading of the GCC and shared libraries under Linux. How to build shared libraries. Most of the material would come from Mitchum DeSouza's GCC FAQ. * KERNEL HOWTO. How to upgrade and compile the kernel. Basic kernel tweaking, including how to turn on debugging output. How to decrypt panic messages. Basic introduction to kernel structure and hacking. (Under constructions, mdw@sunsite.unc.edu). * SERIAL HOWTO. All of the ins and outs about serial communications under Linux, including use of getty for dialins. Perhaps a section on FAX software. 3. Writing and submitting a HOWTO If you would like to write a Linux HOWTO document, there are a few guidelines that you should follow. * Format the document neatly. HOWTOs must be available in plain ASCII format, but you are free to use a formatting tool (texinfo, LameTeX, nroff) to format the document. Try to use meaningful structure and organization, and write clearly. Remember that many of the people reading HOWTOs do not speak English as their first language. * Make sure that all of the information is correct. I can't stress this enough. When in doubt, speculate, but make it clear that you're only guessing. * Make sure that you are covering the most recent version of the available software. Also, be sure to include full instructions on where software can be downloaded from (FTP site name, full pathname). * Include an FAQ section at the end, if appropriate. Many HOWTO documents need an "FAQ" or "Common Problems" section to cover information which can't be covered in the regular text. * Use other HOWTOs as a model. It is nice to have a common look and feel to HOWTO documents--- this document being an example. The easier the HOWTO is to browse, the more useful it will be to readers. After you have written the HOWTO, mail it to me (Matt Welsh) at mdw@sunsite.unc.edu. I am the HOWTO coordinator---I will look over the HOWTO, and make any editorial remarks. I will also take care of approving and posting the HOWTO to the various newsgroups and uploading the HOWTO to the FTP archive sites. Of course, all credit for the HOWTO will go to the author. It is important that you go through me when submitting a HOWTO. I maintain the HOWTO archives and need to keep track of what HOWTOs are being written and who is doing what. If you don't submit a HOWTO to me, I can't include it in the archive or add it to the HOWTO INDEX. I can also help to reformat the HOWTO if needed to make it look nicer. :) Once I have approved the HOWTO, I will post it and upload it to the FTP sites. I will also send you (the author) the "final" version of the HOWTO with any changes. All you have to do is send me periodic updates (every month or so, as needed) and I will take care of posting the HOWTO regularly. 3. Miscellaneous and Legalese If you have questions, please feel free to mail mdw@sunsite.unc.edu. The Linux FAQ rewrite is being coordinated by Ian Jackson, ijackson@nyx.cs.du.edu, with help from others. Linux HOWTOs are copyrighted by their authors. You are free to distribute verbatim copies of HOWTOs in any medium, provided that the copyright notice and authorship remains intact. ------------------------------ From: csk@lm.dth.dk (Claus S. Kristensen) Subject: Corel SCSI LS2000 card [Q] Date: Sun, 31 Oct 1993 19:00:29 GMT Hi Linuxers! (I appologize if this is the wrong newsgroup for this question - I'm new to this hierachy and don't know which is where...) I have just obtained the Linux (Yggdrasil) CD and have tried to run the system by booting on the Bootdisk. However, I can't get linux to recognize the Corel LS2000 SCSI card I have for my Toshiba CD-drive. The chip on the card is a NCR53C400. I have tried to disable the BIOS but it didn't help. Any (ANY) suggestions are wellcome. (Yes, I know it's not on the list of approved adaptor cards, but if someone knows how to make it work anyway, i'd be very glad) Sincerely, Claus Kristensen ================================================================== * Claus Sternberg Kristensen, PhD * * Department of Microbiology Technical University of Denmark * * Building 221 DK 2800 Lyngby Denmark * * Phone (Den:) 45 93 12 22 ext. 2522 or 2515 * * Phone (Int:) +45 45 93 34 22 FAX +45 45 93 28 09 * * E-mail: csk@lm.dth.dk * ================================================================== ------------------------------ From: jacobsd@solar.cor2.epa.gov Subject: Re: BIG Security Hole in SLACKWARE Date: 31 Oct 1993 18:16:28 GMT In <2b0fgh$2ik@knobel.knirsch.de> andreas@knobel.knirsch.de (Andreas Klemm) writes: >pott@asterix.nt.ruhr-uni-bochum.de (Ruediger Pott) writes: >>I just experienced a big security-hole in the current >>Slackware-Distribution: >What do you call current ? In Slackware 1.0.4 >ls -ld / shows: >drwxr-xr-x 16 root root 1024 Oct 24 16:31 / >>The root-directory is writable for everyone!!! >Is this bug perhaps in 1.0.5 ???!!! I have Slackware 1.02 and / was world writable. I suspect that it was a bug in the earlier versions. I believe it used to be around in SLS where Slackware sort of came from, and got fixed. I'm glad it got fixed (if it did) because there are a _lot_ of holes in 1.02. Some other fun tricks for Slackware: tftp is enabled on /, root's .profile has the line umask 000 (which causes all new directories made to be world writable!), and a number of other directories are world writable, as are devices. I strongly suggest running COPS once to see what it shows. If you have users on your system, they might run it, and I'm sure you want to do it before they do! BTW, this should not be entailed as a flame against Slackware -- I first decided to install SLS, then after getting about 20 pages of "bugs to fix after installing but before running" tips from people (all of which was available to Peter MacDonald but he seems to have ignored), I went with Slackware instead. I'm glad I did, and Patrick Volkerding has actually answered my mail very promptly. -- Dana Jacobsen jacobsd@solar.cor2.epa.gov Computer Sciences Corp. "In legislative bodies, it is customary to mention all members as honorable; as, `the honorable gentleman is a scurvy cur.'" -- Ambrose Bierce, "The Devil's Dictionary" ------------------------------ From: jliddle@rs6000.cmp.ilstu.edu (Jean Liddle) Subject: Re: BIG Security Hole in SLACKWARE Date: Sun, 31 Oct 1993 17:34:23 GMT In article <2b0fgh$2ik@knobel.knirsch.de> andreas@knobel.knirsch.de (Andreas Klemm) writes: >pott@asterix.nt.ruhr-uni-bochum.de (Ruediger Pott) writes: > >What do you call current ? In Slackware 1.0.4 >ls -ld / shows: > >drwxr-xr-x 16 root root 1024 Oct 24 16:31 / > >>The root-directory is writable for everyone!!! > >Is this bug perhaps in 1.0.5 ???!!! > in my version of 1.0.5 ls -ld / shows: drwxr-xr-x 17 root root 1024 Oct 31 01:40 / as well. Perhaps this has been fixed since you downoaded 1.05? Jean. -- Jean Liddle Computer Science, Illinois State University e-mail: jliddle@ilstu.edu ============================================ ------------------------------ Crossposted-To: comp.os.linux.misc,comp.unix.questions,comp.unix.misc From: rlm@helen.surfcty.com (Robert L. McMillin) Subject: Re: Introduction into Unix Date: Sun, 31 Oct 1993 17:12:06 GMT On 30 Oct 1993 04:22:44 GMT, muenx@heike.informatik.uni-dortmund.de (Holger Muenx) said: > Due to the fact that some of my users are no Unix wizards I am looking for > some introduction paper for them to learn the basics. > It's for a Linux system but needs not to be special written for this OS. > It would be fine if it is available as plain ascii file. However, dvi or > postscript will do it too. Even references to printed books/papers will > be interesting for me. > Please tell me the exact locations and names of mentioned files! Not an e-text, but how about the O'Reilly & Associates book on Unix? -- Robert L. McMillin | Surf City Software | rlm@helen.surfcty.com | Dude! "It's okay to stare at my ear. I know you can't help it." -- Bongo ------------------------------ From: ddd42961@uxa.cso.uiuc.edu (Daniel D Deavours) Subject: Re: Is PLIP possible form a LAN? Date: 31 Oct 1993 21:23:33 GMT >> Just want to ask, if every of my computer have 2 or more parallel ports, >> can (theorically, dispite the bugs) PLIP forms a LAN which is connected >> like this :- >> >> +-----> Computer A <----+ >> | | >> \/ \/ SLIP >> Computer B Computer C <--------> SLIP server (Internet gate) >> /\ /\ >> | | >> +----> Computer D <-----+ >The answer is surely yes, although the routing tables would have to >reflect this. (In thinking carefully about my suggestion below, I >realized that in the configuration above if A is talking to D via B, B >will have to take 2 interrupts (one in, one out) for every character >passed along, which will limit your throughput.) Pretty close, however, the way the driver is implimented is that there is only 1 interrupt per a plip packet, and that is when a machine gets a request to send message. The rest is done by polling! The reason is simple. Performance. There is no way a PC could handle 25000 interrupts a second. The 25k/sec is realized over really fast machines that have good connections running in a tight polling loop. I know, I've experimented with it. There are several problems with the PLIP idea, mainly reliability of transmissoin. The transmission is asyncronous connected to dumb hardware and driving a very capacitive line. This means you have to wait until the line settles for each byte sent, and for maximum performance, this has to be done while polling. So basically your machine sits there waiting for bytes to come in. So in this case, on a high traffic connection, machine B would grind to a crawl. >What I've been thinking of is: > +-----------+-----------+-----------+---- pullup resistors > | | | | > \/ \/ \/ \/ > Computer A Computer B Computer C Computer D <---SLIP to Internet >by connecting all the parallel ports via open-collector driver chips. >You would have to do an ethernet like ``check busy before talking'' >protocol, but that wouldn't be too hard to do. The advantages: only 1 >parallel port required per computer, fewer interrupts on intermediate >computers (they'll get the interrupts but can ignore them unless the >message is for them), you can plug/unplug computers at will (handy for >laptops) and the throughput should be the same (which is to say you're >not losing anything without the second parallel port, as somebody >quoted 25Kbytes/sec which is clearly interrupt-handling limited, as >the hardware is capable of 400Kbytes/sec). >Any comments from any people who know more about hardware than I do? I've experimented with some different hardware ideas, mainly the full width bidirectional parallel port, sending a full byte at a time (as opposed to half a byte in the current implimentation.) Also, on the software end, using a different protocol that doesn't send ACKs for each byte. I was able to get performance throughput substantially higher, like around 80k/sec. But on a *real* system, I would have to either disable interrupts for a long time or expect to drop packets like crazy, neither which are attractive. A better idea comes from IBM. In their high end PS/2s, they have DMA's on their bidirectional parallel ports, which is the really ideal solution. However, when you're looking at that in terms of cost, a 10mb eithernet card is very little more $$, and performance is better in an order of magnitude! So in short, PLIP is a dead end solution. Eithernet is MUCH faster and MUCH more effecient. And to impliment something better than the standard PLIP driver would probably cost just as much. That, and the burdens of school work is what motivated me to give up on the faster PLIP solutions. Your idea for a PLIP network would work well. It's fairly similar to the SCSI-1 bus. But to put together the cards, cable, connectors, write the software, and realize that the parallel port was not designed to read data at high speeds... you're looking at a non-trivial cost. In short, eithernet is very cheep and performance is awesome. For the cost for performance, it can't be beat. Dan zeos@uiuc.edu ------------------------------ ** FOR YOUR REFERENCE ** The service address, to which questions about the list itself and requests to be added to or deleted from it should be directed, is: Internet: Linux-Admin-Request@NEWS-DIGESTS.MIT.EDU You can send mail to the entire list (and comp.os.linux.admin) via: Internet: Linux-Admin@NEWS-DIGESTS.MIT.EDU Linux may be obtained via one of these FTP sites: nic.funet.fi pub/OS/Linux tsx-11.mit.edu pub/linux sunsite.unc.edu pub/Linux End of Linux-Admin Digest ******************************