2.2. Conoscere i problemi generali di sicurezza

Questo manuale (per lo più) non entra nei dettagli sul perché alcune richieste siano considerate a rischio per la sicurezza. Tuttavia potreste desiderare acquisire una maggiore preparazione sulla sicurezza generale su UNIX e (specifica) in Linux. Dedicate un po' di tempo alla lettura di documenti riguardanti la sicurezza, per prendere decisioni informate di fronte a scelte diverse. Debian GNU/Linux si basa sul kernel Linux, quindi vi si applicano molte delle informazioni disponibili per Linux, anche di altre distribuzioni, e sulla sicurezza in generale degli UNIX (anche se sono differenti gli strumenti usati o i programmi disponibili).

Alcuni documenti utili sono:

The http://www.tldp.org/HOWTO/Security-HOWTO/ is one of the best references regarding general Linux security.
The http://www.tldp.org/HOWTO/Security-Quickstart-HOWTO/ is also a very good starting point for novice users (both to Linux and security).
The http://seifried.org/lasg/ is a complete guide that touches all the issues related to security in Linux, from kernel security to VPNs. Note that it has not been updated since 2001, but some information is still relevant. ^[1]
Kurt Seifried's http://seifried.org/security/os/linux/20020324-securing-linux-step-by-step.html.
In http://www.tldp.org/links/p_books.html#securing_linux you can find a similar document to this manual but related to Red Hat, some of the issues are not distribution-specific and also apply to Debian.
Another Red Hat related document is https://web.archive.org/web/20050520170309/https://ltp.sourceforge.net/docs/RHEL-EAL3-Configuration-Guide.pdf.
IntersectAlliance has published some documents that can be used as reference cards on how to harden Linux servers (and their services), the documents are available at https://web.archive.org/web/20030210231943/http://www.intersectalliance.com/projects/index.html.
For network administrators, a good reference for building a secure network is the https://web.archive.org/web/20030418093551/http://www.linuxsecurity.com/docs/LDP/Securing-Domain-HOWTO/.
Se volete provare i programmi che state per utilizzare (o se volete elaborarne dei nuovi), dovreste leggere http://www.tldp.org/HOWTO/Secure-Programs-HOWTO/, che include illustrazioni e brani parlati dell'autore, David Wheeler, la cui stesura originale è disponibile all'indirizzo http://www.dwheeler.com/secure-programs/.
If you are considering installing firewall capabilities, you should read the http://www.tldp.org/HOWTO/Firewall-HOWTO.html and the http://www.tldp.org/HOWTO/IPCHAINS-HOWTO.html (for kernels previous to 2.4).
Finally, a good card to keep handy is the https://web.archive.org/web/20030308013020/http://www.linuxsecurity.com/docs/QuickRefCard.pdf.

In any case, there is more information regarding the services explained here (NFS, NIS, SMB...) in many of the HOWTOs of the http://www.tldp.org/. Some of these documents speak on the security side of a given service, so be sure to take a look there too.

The HOWTO documents from the Linux Documentation Project are available in Debian GNU/Linux through the installation of the doc-linux-text (text version) or doc-linux-html (HTML version). After installation these documents will be available at the /usr/share/doc/HOWTO/en-txt and /usr/share/doc/HOWTO/en-html directories, respectively.

Altri libri suggeriti su Linux:

Maximum Linux Security (Il massimo della sicurezza in Linux): la guida di un hacker per proteggere i vostri server e le vostre reti Linux. Anonimo. Tascabile - 829 pagine. Sams Publishing. ISBN: 0672313413. Luglio 1999.
Linux Security (Sicurezza in Linux), di John S. Flowers. New Riders; ISBN: 0735700354. marzo 1999.
https://web.archive.org/web/20030202131658/https://www.linux.org/books/ISBN_0072127732.html By Brian Hatch. McGraw-Hill Higher Education. ISBN 0072127732. April, 2001

Altri libri (che possono riferirsi a esigenze generali su UNIX e sulla sicurezza, non specifiche per Linux):

https://web.archive.org/web/20030206231652/http://www.oreilly.com/catalog/puis/ Garfinkel, Simpson, and Spafford, Gene; O'Reilly Associates; ISBN 0-56592-148-8; 1004pp; 1996.
Firewalls and Internet Security (Firewall e sicurezza internet), Cheswick, William R. e Bellovin, Steven M.; Addison-Wesley; 1994; ISBN 0-201-63357-4; 320pp.

Alcuni siti web utili per mantenersi aggiornati sulla sicurezza:

http://csrc.nist.gov/.
https://cve.mitre.org/data/refs/refmap/source-BUGTRAQ.html CVE Reference Map for Source BUGTRAQ
http://www.linuxsecurity.com/. General information regarding Linux security (tools, news...). Most useful is the https://linuxsecurity.com/howtos page.

^[1] At a given time it was superseded by the "Linux Security Knowledge Base". This documentation is also provided in Debian through the lskb package. Now it's back as the Lasg again.