Host Integrity Monitoring Using Osiris and Samhain 50
nazarijo (Jose Nazario) writes "When you arrive to work one morning, you find that your coworker's workstation
is acting funny. A quick forensic examination reveals it's been compromised
and used to scan the network for more vulnerabilities. When did this
happen, and where else is this going on in you domain? With a host
integrity monitoring solution, you'll be a lot further along at answering
those questions than piecing it all together after the fact. And you
can accomplish this with two freeware tools, as described in Host
Integrity Monitoring Using Osiris and Samhain, a new book from
Syngress Publishing." Read on for the rest of Nazario's review.
| Host Integrity Monitoring Using Osiris and Samhain | |
| author | Brian Wotring, with Bruce Potter and Rainer Wichmann |
| pages | 450 |
| publisher | Syngress |
| rating | 8 |
| reviewer | Jose Nazario |
| ISBN | 1597490180 |
| summary | Use freeware tools to ensure your site's security is intact |
Host integrity monitoring is the process by which system and network administrators validate and enforce the security of their systems. This can be a complex suite of approaches, tools, and methodologies, and it can be as simple as looking at loggin output. In the past, tools like Tripwire were used to check the configurations on hosts. The freeware version of this tool was limited in its manageability, which was available mainly in the commercial version.
Tools like Osiris and Samhain came along to fill the gap and have since evolved into mature projects themselves. Like any existing software tool out there, any new book should be evaluated not only on its own but also in he context of the existing documentation. Both Osiris and Samhain have decent amounts of documentation available already (Samhain seems to have a larger user documentation repository online than the Osiris tool does), and the book contributes to these docs quite well.
Host Integrity Monitoring shows you how to set up these tools and put them into production on Windows, UNIX, and OS X. Wotring's writing is fairly good, and his examples are usually pretty clear. The pace of the material is good, and there's not a whole lot of domain-specific expertise beyond system administration skills required to make use of the book. At times some of the formatting of the text gets in the way, but that's trivial compared to the quality of writing (which is pretty good).
Overall the material in the book is decent. The book opens with an overview of what host integrity monitoring is, why you should use it, and some of the basic premises. Then it goes on to discuss Samhain and Osiris, starting with their basic installation and then on to their advanced usage. They differ enough that each project merits its own pieces of documentation, even though they're similar in spirit. You'll learn how to schedule scans, integrate with other tools like Swatch, and in general administer a site installation.
The author of the book, Brian Wotring, is more familiar with Osiris than he is with Samhain, and it shows. More material (100 pages) is devoted to using Osiris than is given to Samhain (60 pages), which is to be expected. The coverage of both is sufficient, though, and fills the major parts of the book.
There are three major strengths to this book over the existing docs. The first is seeing not just the tools themselves covered but also the threats they cover in place. The second is having the two tools covered side by side, allowing you to see how to accomplish the same task with each. And thirdly, there are two appendices that are true gems of this book. The first covers how to get your Linksys Linux based AP device monitored using the Osiris tool, which isn't a small feat. The second is how to write your own modules for Osiris and Samhain, for which this appears to be the only documentation for Osiris (Samhain's website has a How To on writing modules). Again, these add value to the book over the freely available documentation.
I would have liked to have seen the chapters devoted specifically to Osiris and Samhain, chapters 6 (Osiris) and 7 (Samhain) broken up into two or three chapters covering their installation and use. The length of these chapters can make finding some material difficult at times. I would have also have liked to see the use of the "bold is input, normal text is output" technical book convention. In many examples finding the user input text can be challenging.
Host Integrity Monitoring Using Osiris and Samhain is not only about these tools but about how to accomplish host integrity monitoring on the cheap (since the code is freely available). While you can find docs on each project, this book complements those docs nicely and provides a nicely wrapped package about how to get the most out of each tool. If you've been thinking about how to ensure that no one is tampering with your system, these tools, and this book, should definitely make your solutions list.
You can purchase Host Integrity Monitoring Using Osiris and Samhain from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Re:Article Text in case of Slashdotting (Score:2)
Sad really, since someone does the same thing for most book reviews.
[1] Although, I admit, this one barely qualifies.
"Samhain" (Score:3, Informative)
"Samhain", Samhuinn, etc: Celtic Quarter Day (Score:5, Informative)
Thus it was believed that this was the night of the dead - a time for the spirits of the departed from the previous year to pay one last visit to their relatives before departing for the other-world forever. Also taking advantage of this closeness between the land of the living and the dead were the mischievous and malevolent spirits of the underworld, and measures had to be taken to protect against their pranks. Thus evolved the tradition of modern Hallowe'en to wear masks - originally to disguise oneself against the unwanted attentions of spirits and faeries.
Another Samhuinn tradition was a market fair held in the nearest trading centre. This was a chance to settle business, to trade livestock and produce of the autumn and to revel with friends for one last time before the winter conditions made travel too difficult. Amongst the entertainments were the Goloshan Plays. The main theme of these ancient narratives was the battle between light and dark, summer and winter. The two characters fight to the death, winter overcoming summer as inevitably as the seasons, but the medicine-man steps in to revive the summer figure, thus ensuring the return of spring and light."
Re:"Samhain" (Score:2)
What's next? Releases of Linux codenamed "Gozer" and "Zuul".
Re:"Samhain" (Score:1)
Cute names slow acceptance. (Score:2)
MOD PARENT UP!
"Funny" names slow the acceptance of many OSS packages.
Marketing is connecting the mind of the prospective customer with the facts of the project. There is as much need for marketing of OSS as for commercial software. However, marketing is an intellectual challenge as big as programming, and most people don't know how to do both.
Re:Cute names slow acceptance. (Score:2)
Oh wait.
Re:Cute names slow acceptance. (Score:2)
I know "marketing" isn't part of software I write, at least not mass-market marketing
Give it an easily accepted name. (Score:2)
The point is that if you want people to use your software, give it a name that is easy for people.
Re:"Samhain" (Score:1)
Re:"Samhain" (Score:2)
Samhain [misfitscentral.com] was the band that Glenn Danzig formed after the Misfits broke up.
Re:"Samhain" (Score:2)
Links would have been nice (Score:5, Informative)
Osiris [hostintegrity.com]
Samhain [sourceforge.net]
Re:Links would have been nice (Score:3, Informative)
AIDE [sourceforge.net]
or Radmind [umich.edu].
I haven't personally heard of anyone using Osiris or Samhain in production.
Honk! (Score:5, Funny)
Scan results:
Workstation infected with Circus_Clown_Virus
Re:Honk! (Score:1)
Never ever ever....
ever
A Bill Hicks virus however, Hmmmm.
Link for those who want to purchase the book (Score:3, Informative)
Arms race (Score:5, Insightful)
Re:Arms race (Score:5, Informative)
While that's clearly a last-line-of-defense sort of thing, it's certainly a welcome feature. I assume that Linux has a similar mechanism, although I haven't personally used it.
System Immutable flag & OS X (Score:5, Interesting)
Very interesting. This FAQ [osxfaq.com] suggest that OS X retains BSD's immutable flag. In theory, the only way to change this flag in OS X is to reboot in single-user mode. I wonder if a rootkit could force a reboot into single user mode, change these flags, and reboot back to remotely own an OS X machine? I would assume that unless the rootkit can insert something into the single-user mode start-up sequence, the system immutable flag should be fairly safe. The big downside would be that System Update would cease to work (and probably create a corrupt partial update) if the wrong file were locked in this way (security vs. ease-of-use again!).
Re:System Immutable flag & OS X (Score:3, Informative)
sudo chflags schg filename is completely effective on a Mac, requiring either a sudo shutdown +0 command or a reboot into Mac OS 9, where the file can then be unlocked from the Get Info window.
Similar functionality can be had in Linux with the lcap command--after making a file immutable, simply remove the CAP_LINUX_IMMUTABLE capability to prevent further modification until the next reboot. For added securi
Re:System Immutable flag & OS X (Score:3, Interesting)
In FreeBSD, the securelevel is set by one of the rc.d scripts that get executed at boot. You could theoretically insert instructions to run before it gets set. Assuming, of course, that the rc.d scripts themselves haven't been made immutable.
You nailed the main drawback: upgrading a running system becomes pretty much impossible without a reboot.
The other one I usually encounter deals with running Aide. Basically, I
Re:System Immutable flag & OS X (Score:2, Informative)
Rebooting and resetting attribs is only possible if the attacker can change one of the programs executed (or utilised) before the runlevel goes out of single user. Consequently if you plan to use this feature serously, you need to examine and protect every file AND DEVICE (/dev/hd* etc) that is read before going into multiuser mode, and their dependants.
This isn't actually as bad as it seems for an already tight sys
Define "Acting funny" (Score:4, Funny)
It won't take my coke. The cup holder keeps spitting it out. And I am expecting to be arrested any moment, as it keeps telling me I'm doing something illegal.
Book author appears to have written Osiris (Score:5, Interesting)
Note to self (Score:4, Funny)
But what about... (Score:1, Funny)
Don't they deserve equal time?
Re:But what about... (Score:1)
These words do not go together (Score:2, Funny)
I read this once... (Score:2)
useful links (Score:4, Funny)
Osiris [progarchives.com]
Samhain [wikipedia.org]
Tripwire? (Score:2, Interesting)
I'm wondering, why hasn't tripwire been improved or forked? It's GPL right?
Re:Tripwire? (Score:2)
I just checked their website and didn't even see the ASR (Academic Source Release) Tripwire version on the website, so it may be gone entirely now. I am sure you can find it out there on the net, but it's not licensed for free commercial usage.
AIDE was developed to get around that, some years ago.
For a good reference list:
Re:Tripwire? (Score:2)
b) if you ever had a look at the (GPLed) code of the open source tripwire release, you would know that it's a mess. the codebase is MUCH larger than that of any other file integrity scanner, it is void of any useful comments, and simply stated, it is what coders call 'spagetti code'.
Nobody wants to improve or fork that thing - it is faster and easier to write
Advantages to Samhain over Tripwire (Score:3, Interesting)
Some useful features that it has which Tripwire doesn't is the ability to monitor kernel system call tables for changes (a common attack vector), and to run as a daemon to alert on changes immediately.
Its definitely worth a look.
"it can be as simple as looking at logging output" (Score:2)
Looking at logging output in an enterprise environment can be very difficult. To make this really useful you need to aggregate information in a central repository, from all different servers/apps running on many machines. For true heavy duty log analysis you need to resort to tools such as SenSage [sensage.com]'s log storage/analysis tool.
Any other tool will choke on the volume of information you'll be chugging through in an enterprise environment, unless you pay for a multi-million-dollar Oracle deployment.
A Linu