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Web Services - More Secure or Less?
visibleman asks: "I have recently moved onto a project which is based around web services and SOAP and have, therefore, been doing some reading on those subjects. One thing which keeps coming up is that web services are claimed to be more secure than CORBA and RMI because it means drilling less holes through firewalls. If I was a firewall administrator (I am not, I am a developer) I would want to know that if I open up a port (port 80 for instance) I know what kind of requests are coming through it. Since SOAP is essentially a mechanism for sending functional requests over a port specified for web page requests this would make me nervous. My preference would be that requests for web pages go over one port and requests to run services go over another - favouring an IIOP solution. Am I off my trolley or would other Slashdotters have similar fears?"
The security or insecurity of a service has nothing to do with whether or not the request can be brokered by a webserver. All this really accomplishes is setting up the webserver as a massive single point of failure, and making it harder to audit what services a particular box is running.
When you use the paradigm that each service has an associated port, you can be sure that nobody is running any unknown services merely by blocking ports. When everything is on port 80, the firewall becomes much less useful.
I don't think it matters which you use. Allowing people to make functional requests to programs inside your firewall is just as much of a security risk either way. I actually think the function call model is an evil, misleading, broken way of thinking about messages over networks, but like several other practices, people seem bound and determined that this is the way to do things. If you must do this evil thing, it probably doesn't matter (from a security standpoint) how you do it.
The only thing you really gain by not going through port 80 is that the attacker theoretically won't be able to break into your web server software by breaking into your RPC software, but I wouldn't count on that being the case. Besides, either way, they've gotten onto your box, does it really matter how?
Holes in firewalls aren't intrinsically bad things. It's what they lead to that's the problem.
Need a Python, C++, Unix, Linux develop
Off the trolley, I'd say. It's a fundamental and unavoidable weakness of packet firewalls that they filter ports, not services. It's completely naive to believe that port 80 will always be harmless HTTP traffic. ANYTHING can run on port 80, and there's nothing you can do against it unless you have absolute control over all machines behind the firewall.
The illegal we do immediately. The unconstitutional takes a little longer.
--Henry Kissinger
I agree with you, the seperation of the ports is more secure due to the fact you need to do less filtering to monitor the incoming requests. However this assumes a competent administrator setting up the firewall, and your code is secure.
Forcing requests to utilize web services is an easier security model. Singular port monitoring is required and ddos, proper request structure, overflows and the like are handled by the web server, thus abstracted from your application layer and upgradable with less affect on your development. Also its assumed you are using a professional level web server (Apache, Iplanet, NES, or even IIS), meaning a greater user base resulting in problems getting found quicker and fixed faster.
$sig=$1 if($brain =~
I totally agree with the idea that separate services receive separate ports. This makes a lot of sense for security, in that you can track excatly what SOAP requests are being made to your servers and allows you to shut them off if necessary. Going over Port 80 makes it virtually impossible for a company to disable a SOAP service from the firewall without expensive packet inspection at the firewall. The drawback that I can see with not going over port 80 is trying to get the Networking group to punch a hole in the firewall for that port. A separate port also makes things more secure in that if you want to use SOAP internally to your network, you don't allow other people to easily send SOAP requests from the external network. We use CORBA at my company and we don't open the ports to the open internet, but we do keep them open on internal firewalls. If hackers knew that we had CORBA servers, they could inspect what services we had and possibly do malicious harm.
Separate but equal is what I say.
Having software that talks on a specific port is not too hard to deal with -- port 80, 8080, 1234123, whatever...
I've worked with stuff that required a range of ports (like thousands of them), which is what makes your IP people freak. Far more common than one would think.
+++ UGUCAUCGUAUUUCU
Hi,
SOAP is transport independant. That's one of its (theoretical) virtues. You can implement SOAP over SMTP, HTTP, whatever.
Practically, it does seem fair to say that HTTP is what an awful lot of SOAP tools are going to be expecting, and given that SOAP is still quite bleeding edge, I wouldn't want to try using another transport protocol unless I could afford time and skill to do a lot of fixing up.
However, HTTP doesn't have to run on port 80. Furthermore, most SOAP implementations will be (well, claim to be) happy on HTTPS too, so that's an easy way to do encryption.
As for the 'web page vs functional' thing, well that's not so simple. A request for a page produced by a CGI script is a functional request coming from strangers over the web. SOAP need not be different.
At the moment, if I want to make an XML version of my content available to folks, I might tell them to use HTTP GET with a URL that invokes a CGI program that returns some XML.
In the future, I might want to make the same XML available via the getXML method my Website class, and then SOAP enable my Website class.
The differences isn't that great.
-----
We are currently using SOAP-like mechanisms, and there are a number of security precautions that can be implemented that in my opinion balance the threat of accepting such messages.
Possibly the most secure precaution is using SSL for the requests. You can require a client certificate to access the service and your site certificate will reassure your partners that they have connected to the correct server. In addition, you can build in custom username/password fields into the app, or have each message PGP signed.
Another option is to move your application to a different IP address and use the firewall to restrict access to it. This method is good if your partners are known ahead of time.
Hope this helps.
It shouldn't matter what ports you open up on your firewall - what you are interested in is what will be receiving these requests.
We've all seen that access to port 80 can cause problems with incorectly configured IIS machines anyway.
Basically as a person responsible for security and firewall configuration you don't just enable access on a port just because someone asks for it - you check out what is going to be used and make a decision AND warnings to those involved.
Matt Thompson - Actuality - Insert product here.
You can use any port you choose. A bit "security through obscurity" this one, but no harm there>
You don't really need a full web server. All you're going to get is an HTTP request with a SOAP envelope thingy inside. If it doesn't match the WSDL (or whatever) schema thingy you've published, then just ignore it. You only need give the information to people who are going to be legitimately calling your service. Of course you're still vulnerable to normal DoS, but then isn't everyone.
It is quite possible to digitally sign SOAP requests. Just ignore anything not signed/not signed by a recognized customer.
If you are only exepcting SOAP requests from a few other servers, then consider client-side SSL. Since only a few servers will be calling you, then you'll only need a few client certs.
... well ... you get what you ask for. Signatures on SOAP requests aren't (easily) supported by everything yet - but then SOAP implementations differ (eg MS SOAP has no types, IBM SOAP does). This isn't a major issue as it's pretty easy to roll your own request - it's only XML after all.
Like everything, it's as secure as you make it. If you expose "FuckMyOS" as a SOAP method and publish it through UDDI or something then
PS I have no opinion on Vladinator's website.
This sig made only from recycled ASCII
The real reason HTTP and port 80 is seen as neat is that it is probably already open, so you don't have to deal with that mean old network admin who just wants to spoil your fun.
You don't have to answer difficult questions about how your service is secured, how it might be exploited to reach other resources within the firewall, etc. You ride the coattails of the "harmless" web server traffic.
"Rub her feet." -- L.L.
IMO you should run separate functions on separate ports. I don't think this increases or decreases security much, but it greatly improves scalability.
I could, for instance, run my setup on a single box; and then, when traffic went up and the service got popular, replace the box with a Linux firewall to an intranet. The functions could then be divided among several machines on that intranet, and having the firewall box route different ports to their dedicated machines would be a trivial task.
Hell, you could even have redundant machines for critical operations, and if a failure occurred you need only change the routing on the firewall box to get things back up.
My real concern about tunneling everything through a single port or protocol is that it makes network auditing much more difficult. If there is a security problem, or just a general network problem, the fact that everything looks like HTTP doesn't help track down the problem.
However, there is a flip side to this. I have been in the position of trying to convince large companies to change their firewall configurations. It would be easier to make lead in to gold than to get a large company to allow communications through a new port on their firewall.
This basically means that putting everything through port 80 serves two purposes. It give people the perception of security, and it lets the project actually happen. It is the case that not having to change your network configuration is a powerful marketing tool, but it doesn't make anything more secure. All of these issues are addressed in just about every networking book out there.
Portals are nice, from a security perspective. You can run all your applications behind a front-end webserver, only accessible via port 80. Some nice firewalls, like Checkpoint, have an HTTP security server which does bounds checking and similar to HTTP requests. Couple this with a good, reliable webserver (apache or netscape), and any applications running behind the portal are less susceptable to an overflow attack since the only machine that can access these applications is the webserver, which means an attacker would have to compromise the web server first.
Also by doing portals in this way, you can force users to authenticate an HTTPS session before accessing the portal site, and the services behind the portal. Of course, how you do authentication can be anything from login/pass to securid or X.509 certificates. Once the users authenticate themselves, then accessing the applications "through port 80" is more secure.
However, setting up multiple DMZs is the way to go. In my example above, where the webserver accesses the services behind the portal, you'd set up those applications in their own DMZ (seperate from the webserver DMZ). Access to this DMZ wouldn't be allowed directly from the outside (restricted by FW), which again would require a compromise of the web server. The other advantage is, if an attacker were to compromise the application *somehow* without a webserver compromise, then this would restrict them to only boxes in this second DMZ and therefore would not compromise the webserver ALSO. Setting up a DMZ correctly means a lot. You can set up a DMZ to accept incoming connections but not to allow anything outbound (except for state traffic). This would prevent an attacker, who has compromised services in the DMZ, from attacking anything else from that point into the rest of your network.
This is definatly a valid question, and I think, personally, the answer would be yes, the entire notion of web services have some serious security reprocusions. In the past, web traffic was web traffic. Now that HTTP is being used to essentially tunnel an RPC call into your servers, it means that that same servers that have, time after time, been compromised, are now the same servers providing vital access to critical data systems.
Now, this does NOT mean that web services are bad, simply that web services have to be written with the understanding that they ARE more open then normal simple RPC calls. Greater use of this design means greater risk in general, since now access to functions that may be suseptable to buffer overflows, denial or service attacks, etc, are basically sitting out there in the open. I've never heard of a denial of service attack targeted at an RPC mechanism, but with little or NO modification, this type of attack could be deployed 'out of the box'.
New security measures will have to be created in order to thwart this greater risk that will now be exposed.
-- I'm the root of all that's evil, but you can call me cookie..
This isn't a perfect analogy, but think of it like a building, where port 80 is the front door that comes into the foyer. The windows are miscellaneous ports, and the loading dock is some port you use for something else (maybe 22).
Let's say you have a security system hooked up to the front door, the windows, loading dock doors etc. Normally pretty much anyone is allowed to walk through the front door. You do hope nobody manages to climb in through a window, and you have strictly controlled access via the loading dock.
Now if your reception is poorly designed your only hope is that nobody who walks through the front door hacks off the head of your receptionist and proceeds to go walkabout through the building screwing with things. If your reception is well designed this will be hard to do.
You could even have it so that there's some hazard to those right there in reception but breaking out of reception is as hard as breaking in any other way. But you don't just assume it's secure because it's nicely decorated or (in this case) because so many people walk through receptions it *must* be secure.
It's just a security model. If you alter the constraints and facilities of the environment, then you've also changed the range of threats to that environment. And you tailor the prophylactic security, intrusion detection and response to the potential threats and damage of compromise.
Overall, if you want to have any security, you have to think about security. However the hell you set up your systems.
It's a new trend, run everything on port 80 so your network admin has less to worry about, but that whole concept is a steaming pile of shit.
So true.
It's taken many years to build up the many layers of network security we have. One of the main reason SOAP is so easy to use is that it drills a hole right through all those layers. In other words, SOAP is easy because it encourages you to ignore everything that makes remote applications hard -- like security.
As an example of just how wacky the everything-on-port-80 idea is, and how dangerous, consider this idea I heard from Bruce Schneier: implement IP over SOAP: have a SOAP service listening at two endpoints for IP packets, and forward those packets over SOAP to the other endpoint. Then make one of those endpoints the default gateway for packets into the otherwise-secure network at the other end....
Just ponder that.
After posting my last reply, I thought of something that is a GOOD thing regarding SOAP over HTTP that deserves mentioning. By directing and detecting all web traffic, you now have a transactional log off all RPC calls being made into your system. So while yes, you are possibly exposing things, you have a much better logging mechanism in a central location then you would have by having any given application tunneling thru its own socket, making calls to its hearts content. All calls cal now be logged, filter, redirected, etc..
Now of course, this does apply only to SOAP over HTTP, and possibly not SMTP/POP3, Raw socket, MSMQ, etc..etc..
-- I'm the root of all that's evil, but you can call me cookie..
Bruce Schneier covered this more than a year ago in the 15.06.2000 cryptogram. Anyone who has read Schneier's newsletter long enough begins to realize that he is the Cassandra of the Internet...
SOAP has actually gone well out of its way to allow server admins to filter requests. It makes use of the "Mandatory Header" aspects of the HTTP protocol such that every soap request must come with an HTTP header specifying which function is being called. Since it's in the header, a server doesn't need to know SOAP to filter, it justs needs to know HTTP, and the server can simply turn away anything that doesn't provide such a header.
I agree there is still a major lack of support for this type of filtering, and even the standard leaves something to be desired in this respect, but the SOAP designers definitely did think that this was a big enough problem to provide facilities for future closing of these holes.
It's a bit of a pain to administer, but it definitely *can* be done.
This is a non-issue. You can run any protocol over any port. If you thwart your own firewalls by running all services through the same port that's your own damn fault (or your clients' fault).
It's 10 PM. Do you know if you're un-American?
I don't know about you, but this thing seems much more like-- Firewall Enhancement Protocol. The writers of this rfc seem to think that this is the best thing for the internet since OSPF....
Seriously-- allowing ANY sort of RPC through a firewall has some serious risks.
LedgerSMB: Open source Accounting/ERP
Yes, another port would be simpler to secure. Without that, firewall administrators will simply go higher in the stack and look at layer 7. In other words, the firewall will have to pick out the URL and apply rules to that. Of course, this also implies the firewall is tracking connections, etc. It can no longer be just a dumb packet filter, but no serious firewall is.
In the end, the lack of a port as a service differentiator isn't a big deal. What is important is that you have something wich differentiates the service. A URL can do that, it just costs a little more CPU.
I wonder if anyone is working on this?
Having done sys admin work, it's much easier and less work to go through port 80. That's one less port to keep track of and allows me to build expertise on securing HTTP. Learning to secure a lot of different ports isn't hard though time consuming. Teaching it to new staff and making sure they understand all of it isn't. That's one reason for the adoption of SOAP and other XML/HTTP protocols.
From a developer perspective, would you rather build in IPSec to your IIOP, CORBA application, or setup HTTPS and go through a well tested system? Rolling your own security on top of IIOP and CORBA isn't a trivial task. You could build your own encryption wrapper for IIOP or CORBA, but you would have to handle all the key storage, key management, encryp/decrypt, secure sessions, and authentication to create robust, reliable security.
If your application really needs greater than 128bit SSL, then going through a web server on port 80 doesn't do anything 4 U. To my knowledge RMI can make HTTP connections via java.rmi.server.RMISocketFactory. There are existing Java libs to handle both SSL and key management, so going with port 80 is really a administration choice.
Off the trolley, I'd say. It's a fundamental and unavoidable weakness of packet firewalls that they filter ports, not services. It's completely naive to believe that port 80 will always be harmless HTTP traffic. ANYTHING can run on port 80, and there's nothing you can do against it unless you have absolute control over all machines behind the firewall.
;)
Hmmm.... Not only can XLM-RPC and SOAP also run on port 80, but that HTTP traffic can be mighty harmfull... Thinking of Nimda, Code Red, and CRII.... The problem is that any "protocol" is fundamentally used to exchange instructions and these instructions can be used for all sorts of stuff.... So filter based on services, but please keep the services in your DMZ
Basically, this means--
filter based on IP address and port number. only allow those things to pass through the firewall that you absolutely need (possible exception of outgoing TCP connections, at your discression) and keep it all inventoried.
LedgerSMB: Open source Accounting/ERP
Right. Why stop at serving bulky data, when you can wrap the bulky data in more bulky data.
Why? Ask anyone who writes tools that piggyback off of Ebay if they wish Ebay supplied XML representation of auction data. They will pee themselves, then scream out loud with joy. XML provides a way to exchange data that is human and machine readable. It also responds well to compression, due to redundancy.
If you fall off a building, go real limp, because maybe you'll look like a dummy and people will be like hey, free dummy
I asked pretty much the same thing of Microsoft when they first announced .NET (which is closely tied to SOAP) For anyone who's curious, I asked a couple people, so I don't really remember WHO I talked to, but I do know that Scott Gu was one of the people.
Their response?
Developers are tired of being hampered by netadmins, trying to open up unsecure ports just so that DCOM will work. Basically, SOAP is a way to do it where you don't have to open up esoteric and undocumented ports and protocols...
As far as security goes... it's up to the implementors. SOAP does have one advantage over some other forms of RPC, in that it has a few built in forms of authentication and is explicit as opposed to implicit. That means you can't just randomly activate bits of code just because you can log onto a server.
Another advantage of SOAP is that a decent XML coder can write his own parser for the protocol, so you don't have to use the vendor's, and you can customize your parser to only pass safe requests.
Of course, some of the MS people indicated that they felt I should use the MS parser at this point. I haven't seen anything bad with it, but I wouldn't have any qualms about writing my own if the business needs dictated it...
I am disrespectful to dirt! Can you see that I am serious?!
I was contracting at company X a few years ago. I needed to use some piece of software for my project, and the demo site for said software ran on port 8081.
..."
Which was blocked by the company firewall.
So I go ask the admin why it's blocked. I mean, WTF, blocking random _incoming_ ports I can understand, but outgoing ports? When there's already port 80 and 21 wide open? Not to mention DNS[1].
"We don't open it because it's more secure that way", he said. "But it's not more secure!" "YES it is!" "Why?" ".... BECAUSE!"
"Ok but look I could just make an SSH tunnel on port 80 with pppd and I can bypass all that stuff
He replied: "well if you do that, you'll get in a LOT of trouble, and the company is going to sue you! And I warn you because I have logs of everything!"
Now what's really interesting is that I had been running this particular setup (pppd through ssh on port 80) for a couple months already, and nobody noticed.
[1] You think you've secured everything and that no info can get through your highly secure firewall? But have you thought about the DNS?
$ host the.root.password.is.iluvmom.crackersite.net
SOAP was developed specifically so companies (such as Microsoft) can execute arbitrary code through otherwise secure firewalls where all they have to do is get the user to download a simple client program that wraps the commands in an XML format and sends it as an innocent looking HTTP response. It was designed to *solve* the problem of corporate users wanting to run network applications that are verboten or otherwize blocked by their network administrators.
SOAP is designed with security in mind. Security circumvention.
Steven Deering from the IETF had an interesting point about running a bunch of services on top top port 80. If you run a bunch of services on top of port 80, all you done is build a protocol stack on top of things running on port 80 and you've turned TCP into a layer 2 protocol. You haven't solved anything, and in fact, you've moved your problem up a level. This is ridiculous. We need to get back to running separate services on separate ports just as the Internet was designed to do.
Bruce Schneier had an interesting statement on security and SOAP:
. html#SOAP">CryptoGram Newsletter on 2001-June-15:SOAP</a>
<a href="http://www.counterpane.com/crypto-gram-0006
I work for an ASP, and we basically have to build full web applications that function like Office tools, and believe me, port 80 is a necessity.
.jar files being executed. Some of them just don't want to allow anything but port 80.
We need to fire up a java applet on the client machine that maintains a session with the server. We also need to allow chat.
I can't begin to tell you how many million sof dollars we've lost as a company because of large corporations that refuse to adjust their firewall settings to accomodate web applications.
Some of them don't want
If we're only allowed traffic on port 80, which is the case when dealing with 90% of corporate environments, your choice is either a) get the services running over port 80 or b) give up on maintaining your business.
He wasn't trolling. I've spent upto 6 months trying to get a port opened, only to be refused. Work for a bung company owned by another big company that says "You will not open a port", and you have 12 levels of management to go through to even ASK
-- 73 de KG2V For the Children - RKBA! "You are what you do when it counts" - the Masso
To date, there have been a large number of tools dedicated to the creation and deployment of web services, but relatively little thought has been given to relationship management between services (a subset of which is security). Only a handful of companies (e.g., the deftly-named Grand Central and Flamenco) have started to broach this issue.
I think we can expect to see a large amount of activity in the area of what it takes to connect web services in the real world (i.e., with sensitive data, in business-critical operations, etc.) in the near future. One certainly would not one's web services to be abused/cracked as easily as Microsoft's Passport "technology". It will be interesting to see how this new market evolves.
moto411.com
Don't forget that there are a lot of customers out there that can only contact sites on port 80 and 443. I have run into this time and again. You want to use a port other than 80 for admin or security reason, only to find out that your customers security practices don't allow communication to other ports.
This is true for both consumers and business customers.
So while you might want to run a service or application on another port, you might be locked into port 80.
Just something to keep in mind.
Beside, you shouldn't rely on the obscure ports for you security. You should build security into your application from the start. And you should NEVER trust any data that comes from "outside" your applications.
Cheers!
I would say that drilling open a bunch of ports on a firewall is probably safer than opening port 80 and nothing else and running all services through this port. Why do you suppose we have ports in the first place? If everything is supposed to run on just one port, than we should have just an IP address and no ports at all! But we do have ports, 64K of them.
In my opinion, every "server" program running on a computer should have its own dedicated ports which it listens on and performs operations through. For secure operation, you decide which services you need and enable only those services. Since all ports not used by these services are, well, not used, then you should block those ports in your firewall.
Want more security? Most non-computer people simply don't understand the concept of good computer maintainence. I keep telling people that just like any machine, computers need to be well maintained or their operation degrades over time. (And that means that security vulnerabilities become more likely as time goes by without proper maintainence.) This includes software and hardware maintainence. Once you have a well functional system working, you can search for big security vulnerabilities, like unnecessary programs or whatever. Once those are gone, you look for smaller things, like software configuration that might allow an intruder to get increased priveledges. Once those are gone, you can go deeper, by getting some h4x0r programs and torture testing your system (being careful not to mess up other peoples' systems in the process). Once you can't get into your own system, you can go deeper yet by examining and auditing the source code of programs you're running (if the source is available to you). I'm sure there are about 30 other steps in between these, but these four are the big tick-marks I can think of right now. Oh well.
Yes, SSL is a *huge* hole in the idea that a firewall can statefully inspect everything going through and place strong limits on what can be send. To allow SSL, you have to allow arbitrary binary data on port 443.
;-)
The only way to stop it is to block SSL / HTTPS. Ah, that's a fantastic way to increase security
Every large organization I've worked for is like that. They *will not* open new ports, but most of them pay no attention to what's going on on 80, 25 and the few other ports they do allow.
Its hardly surprising: they've all been sold on the all they need is a firewall. Then when they discover they need a policy for that firewall and for handling requests from their staff, they all choose to do "whatever everyone else does". This means HTTP, SMTP and POP bascially. (I'll refrain from commenting on how "secure" those three are.)
I was once told (at a previous job) I couldn't have CDDB because it was MP3-ish and might be used by music pirates. (In case you don't know, its a service for looking up the titles of songs, not getting the music itself. I explained this to the guy. He said "I know" but its still not happening.)
Actually the other thing that goes on is people outsource their firewall management. Every time you call you wait a week to get the person who knows their account, then they charge $$$ per hour to make a change. I think we found the real cause of my "no-CDDB" problem.
Lord Pixel - The cat who walks through walls
A little bigger on the inside than out
I wrote "Web RPCs Considered Harmful" that briefly addresses the security issue.
Summary (and using more recent terminology): Web services that expose more new and unique code are more likely to expose bugs. RPCs, SOAP, and CGIs all encourage developers to write more exposed code by making that style easier to do.
One better alternative is to be more data-driven (some would say "functional", as in "functional programming"), so that you only expose data (via a standard server which would typically be more mature, heavily reviewed code).
Alas, that's an entirely different way of thinking that most people are not used to, since it flies in the face of "normal procedural or OO programming" that happens on the desktop. Some examples, though, are Linda Systems (TupleSpaces), REST (the traditional WWW architecture), and even P2P to a large extent.
One problem with firewalls (especially packet filters) is that it's hard to know exactly what data is flowing through. You can really tunnel any protocol over any other - you just need to know how to encapsulate and decapsulate it. Distinguishing whether data is regular data or encapsulated data of another type is hard to do. So I suspect that security people are going to have a hard time, unless we can convince the developers that they *need* firewalls and to stop tunneling holes through.
Software sucks. Open Source sucks less.
I will now summarize this entire article into two opposing viewpoints:
I tend to agree with the second argument, but until we have powerful stateful protocol filters for all protocols that could go through port 80 or wherever, there's no real difference between opening 50 separate holes or one big one. Even then, bad stuff can get in and out over https, etc. So SOAP doesn't really make things much worse, it just points out security issues that we've been ignoring all along.
Your right to not believe: Americans United for Separation of Church and
... for the SOAP protocol is that Microsoft's ActiveX services use a portmapper to get dynamic port numbers for their services. Needless to say, this is absolute hell to try to run through a firewall with anything resembling security.
Hence SOAP. You piggyback your ActiveX control onto another service (HTTP) that uses a single port. Smart admins will use something other than port 80; we know how many of *those* there are.
There is also the problem that firewall admins tend to take their job seriously -- they know that if anything nasty gets into the network, they'll get blamed for it. They tend to be *very* conservitave. Web admins don't -- most of them think that the worst that can happen if they get hacked is that they'll get pitchers of nekkid wimmen on the corporate homepage. They don't care. *Much* easier to deal with web admins than firewall admins. Lotsa places will even let you have your own web server if you promise to be nice.
As to what it can lead to, check out RFC 3093, Firewall Enhancement Protocol (FEP)
Welcome to the Turing Tarpit, where everything is possible but nothing interesting is easy.
A firewall is the wrong approach anyway. It presumes that you can declare a sure perimeter behind which things can be "trusted."
There are so many ways around most firewalls (modems, wireless networks, unscrupulous visitors, virii on removable media and whotnot) that the firewall is really just the "front door."
End-to-end security -- defense in depth -- is the only way to be sure. Each machine has to be "strong enough" -- just like most office desks and doors are equipped with locks, though most of us don't use 'em.
Clearly we live in a world where most desktops are _completely_ insecure, so firewalls aren't completely worthless. But perhaps SOAP and the like will have some benefit through clueing in some of the clueless that there's more to security than throwing up a firewall.
Mindterm looks interesting, but the GNU httptunnel application (here is another link) mentioned in another post will do roughly the same thing, and you can easily use ssh over httptunnel to tunnel other protocols.
Better yet, unlike Mindbright's applet, httptunnel is free software (GPL). Mindbright's applet does sound like it has some nice bell's and whistles, though. Probably worth paying for if you were going to roll SSS over HTTP out as a solution to a larger group of users. (using ssh over httptunnel works great, but it can be a little confusing to set up the first time.) Otherwise, try httptunnel instead.
BlueCollarTech.com
** The opinions expressed here are my own, and do not reflect those of my employers - past, present, or future**
exception handling is easier in omni's way, but probly not enough to justify the programming overhead. But a message loop is more graceful and more flexible from an OO perspective too. Think about the other latency case -- user interface.
while (response = network_event_handler(request) == NULL)
{
wait();
if (timeout())
{
exception("Time to find out who's running Gnutella");
}
}
Fact is that running SOAP over port 80 or not doesn't make much difference. Someone once said that IT secuirty is 20% technology and 80% policy and practice. These numbers are debatable, but I agree with the premise.
The problem is that certain things have to be open on a networked computer in order to benefit from the networking in the first place. You need layered security. You can't just secure your physical, network and transport layers and expect everything to be okay. You need to know what's going on all the way up to the application layer.
You need to use DMZs, staggered firewalls, SSL, SSH, applications that force you to login, appropriate file/directory/service security permissions. You need to know at any time what software your boxes are running, and make an effort to understand how that software works and what issues it presents. You need to patch commercial software, read the bug lists and do penetration testing.
There's obviously more that can be added to this list, but the point is that security is process not a technical specification, a device...or a choice of port.
Most organizations don't invest enough in this process because those controlling expenditure tend not to understand the importance. Also, security is one of those things you only notice when it doesn't work, so it is assumed you are doing it, and you'll never shine for doing a great job at it.
I think it will take a much more hostile Internet security environment to wake people up to the need to invest in the most critical security capital of all: talented, educated and dedicated human beings.
The issue with SOAP is not one of security - what port you run on is neither here nor there - but the fact that most technologies based on XML are a load of old rubbish.
XML may be a "standard" but so are technologies such as Java serialisation and they work just fine over HTTP. This works automatically and leads to fewer programming errors due to "impedance mismatch", surely the chief source of any security holes and other bugs.
I don't buy the argument that an XML schema is any more future-proof than a Java class spec. Java handles class changes etc. quite elegantly. And I don't buy the "XML is language-independent" line either - it's just hard to read XML in any language. So you have to use that awful Xerces stuff that changes every 2 months, with little backward compatibility between versions.
Don't be fooled - there is simply nothing that uses XML that can't be done more elegantly some other way. XML is not a technology - it, along with SOAP, is a completely pointless standard.
bring your jacket liner to work. or use google. Your company doesn't need to buy more hardware and hire more techs just so you can remember which track is "Hit Me Baby One More Time"
A couple of rebuttals if I may.
Many people claim that one can run services on any port they choose, so port filtering is not the same thing as service filtering. True, but if people ran anything on any port we would have no concept of well-known-services at specific ports. Moving web traffic from port 80 makes almost no sense because that's where everyone is going to look for it by default. There is a high probability, then, that filtering on specific ports will filter specific services.
Network administrators, by default, are highly suspicious and paranoid people. They don't even trust the people they work with, and for good reason. If they could force everyone to use pine or mutt for e-mail reading, I'm sure they would since it is less succeptible to Outlook-born viruses. If development teams would communicate with and seek advice from the security team when developing applications I'm sure there wouldn't be as much hostility to opening a port as there is when approached with "We just wrote an application. Can we have a free port?"[1]. In the latter case, the security team has no idea what the application does or how it was developed and is certainly not inclined to open a port to untrusted software.
Finally, on to the subject of my article, Apache (or whatever server you're running) is the inetd of the future. Look at the facts:
- both listen on one or more ports for requests
- when a request comes in it is dispatched to the correct subsystem
- most security (ssl, https, tcpwrappers) is handled by the daemon before it gets to the service handler
- the service handler can perform further accouting or security checks
- the daemon handles all the networking details on behalf of the subsystem
Add to this the fact that this is all multiplexed on a single port, and configuring your firewall should be a breeze. Virtually anything you can do with inetd you can do with a good web server.Paradoxically, network admins appear less paranoid about their web servers than other inetd-based or standalone services. Some guy codes up a web app and, with little fuss, gets it deployed on the server. No code review, no hassle, no problem! There are only two reasons I can think of for this behavior: 1) The administrator inherently trusts the web server, or 2) the web server box is in a DMZ. I would be suspicious of administrators in the former case.
Despite the security advantages of a DMZ, it is still necessary for application developers to communicate with security people. Say, for example, that a web application is deployed on server in a DMZ and that the machine is later compromized. If the application had a configuration file with passwords for a database, the database should now be considered compromized. Damage can be reduced or prevented by correct configuration of the database (providing write access only to a specific table rather than the whole database), but you should check with the security people before actual deployment.[2]
[1] The standard answer to this question is "No". Note that the administrator only answers the question asked. If you want to be more successful in the future, present a full document detailing what the software does, how it works, and maybe provide the admin with a code review, THEN ask for a port. I know this is a lot of work, but it is necessary to maintain the security of the network. You may not take security seriously, but your administrator does.
[2] Yes, I know that there are moron security people out there. My comment assumes you have good to excellent security people working in your company.
I too have been in your situation many times. Anybody who claims that the private industry is somehow more efficient or clueful then the govt needs to read your post.
War is necrophilia.
host address and protocol?
As most of the forum here says, security doesn't start at the port level. It comes from that application itself. If you SOAP transport accepts data from whoever send it, that is bad (just restricting IP's is stupid as well as it is brainless to spoof that). I would suggest running an authentication method on all trafic coming and going.
This can be done in any number of ways. Signing all the XML data with a GPG key to verify ownership of the data or the cheesy secret key method. Read up on how SSH works and key based authentication will seem like a viable option
Hire me...
OTOH, in order for everyone inside the firewall to use soap application servers on the outside, port 80 traffic has to be allowed in both directions for all machines. Any PC could have a trojaned app installed and the firewall can do nothing about it. Likely as not, those users are less security concious than the admin of a publicly available web server.
I think you're dead on that what's missing is intelligent human beings who can look at a particular instance and correctly apply security procedures, including but not limited to policies, to protect assets to the degree warranted by business needs.
The subject is all I wanted to say...
"Communism is like having one [local] phone company " - Lenny Bruce
You're right. Although many other means of transferring data do not compress well due to their "efficiency". XML responds well to data compression algorythms for several reasons. Unicode text always compresses pretty well. The redundancy is just one aspect.
If you fall off a building, go real limp, because maybe you'll look like a dummy and people will be like hey, free dummy
The problem with IIOP and DRPC is that they encode the communication enpoints as a hard IP address and port in the requests on the wire.
This makes these products virtually incompatable with network address translation (NAT) out of the box. Basically, the NAT boxes will translate a local, non-routable IP address into the IP address of the NAT box with a made-up port number. The problem is they don't modify the IP address and port numbers imbedded into the IIOP message.
There are products that will do this but you have a choice: 1) Teach your admins about another product and install the product both at your site and the client site or 2) teach them how to secure web services using the existing firewalls, load balancers, and SSL that they already understand -- no client site modifications required.
Securing web services properly (IMHO) requires that you have a layer 7 device that can look at the incoming SOAP requests and dump requests for an unknown endpoint on the floor immediately. The you have to make sure the request gets properly validated by the SOAP implementation and application layer.
So on the one hand you have IIOP and DRPC that require additional products or you have SOAP with requires you to apply the products that, if you have a significant web presence, you already have. Seems like an easy choice to me but you have to understand how all the pieces fit together. If you don't have that expertise in house, go rent it from somewhere.
You are not a beautiful or unique snowflake -- but you could be if you got off your ass.
What exactly is it about threads that "encourage" people to use a one-thread-per-client model?
The fact that it's the only available method under some systems. For instance, last time I checked, 100% Pure Java(tm) applications had no nonblocking I/O facility, so you had to open a thread for each concurrent I/O stream.
What is it about RPC that encourages people to to ignore network overhead?
Try developers designing, testing, and optimizing an application on a local LAN and then wondering why it doesn't work across the full Internet.
Will I retire or break 10K?
If you want "soap on a rope", you might want to look at the Remote Object Proxy Engine (ROPE), a part of Microsoft's SOAP implementation that translates COM calls to SOAP calls.
Will I retire or break 10K?
It's not about the connection method, it's the content that traverses the corporate boundary that is the issue.
If the content shouldn't be going over the boundary, then it doesn't matter how you achieved it - you're still in the wrong. You could do it in CORBA, you could do it in simple HTTP GET and POSTs, it doesn't matter.
As a developer, I can make SOAP invisible to all firewall administrators using HTTPS or abusing their firewall's limitations (most firewalls are incredibly stupid - they don't and can't parse even basic protocols like HTTP, thus let anything that goes out on port X out if port X is allowed outbound.
As a person responsible for security, your use of any services not explicitly allowed is probably against security policy. But security policy is there to enable business, not inhibit it. This is the single biggest failing of most security people: they lose sight of why they are there!.
If it takes too long to get a content-flow approved, then that is a failing of the content-flow negotiation process, and it's not about technology at all.
Andrew van der Stock
While i realy don't know jack about networking and security, I can't remember an exploit that made big headlines that ran over a port higher than 1024. The ports lower than 1025 have to be opened by a process that at least initialy has root privs, force a buffer overflow and you've got instant root privs and a wide open system.
if the port is greater than 1024 then any UID can open it, overflow it and you only get the privs of the opening UID. This will usualy stop the kiddies dead in there tracks, you're not going to stop a hardcore hacker that realy wants in anyways, usualy around the firewall through some salesweenies modem and telephone extention.
Another thing is what about outgoing connections? Don't they establish a dialog, you know two way, as in talking also involve listening.
I guess what I'm realy pointing out is security is an illusion, the best you can hope for is to make the effort to hack your system greater than the rewards gained. A computer encased in concrete sitting on the bottom of the ocean is as secure as they get, but not very usefull. Force everybody to go around your security policies, and you've got no security.
<obigatoryRant>
Beside I'll bet that you don't block SMTP, and Email read on one of the Microsoft virus launchers is about as insecure as you can get.</obigatoryRant>
Apocalypse Cancelled, Sorry, No Ticket Refunds
The real problem with this SOAP/"everything over HTTP" thing people are pushing is it's about having two networks that want to talk a lot of arbitrary stuff to each other, on almost any topic unimaginable.
Putting a firewall between such networks is usually counter productive. Because the whole idea of a firewall is to block almost everything. Otherwise what is the firewall for?
Worse, people are actually suggesting that one or both of these networks will be exposed to hostile/unsecured networks.
Think about it. Should something on an unsecured network be able to ask a server on a secured network to run hundreds or thousands of undeterminable remote procedures for it?
That's where the main problem is.
"Mean Old Admin" blocked everything other than HTTP in order to block EVERYTHING THAT PEOPLE NOW WANT TO DO OVER SOAP from getting through to corporate networks. Yes sir, Mean Old Admin thinks that it's a bad idea to have someone outside telling your internal servers to run arbitrary stuff.
"Mean Old Admin" knows that most of those SOAP programmers are clueless about security if not why did they design such a protocol in the first place.
Because if it's on trusted networks why bother with tunnelling, HTTP/XML etc- go direct less overheads. If it's on an untrusted network, you got a LOT of explaining and justification to do.
Seems a lot of programmers couldn't explain and justify why they would want to do everything over untrusted networks that's why they are trying to sneak everything over HTTP.
So can we be sure these people can code this stuff securely?
If a lot of people start doing this, we'd probably need BUGTRAQ-SOAP soon.
A request for a page produced by a CGI script is plain text. The CGI server runs a local, trusted application that outputs a plain HTTP text stream that is sent to the client that requested it (usually a web browser) and is not interpretted (except by javascript or a browser plugin)
SOAP implements the equivalent of allowing a remote host to send executable code to the client over a connection that is expecting plain text. It is the equivalent of having Outlook with VB Macros enabled that automatically executes as soon as an email is *received*. The biggest difference is that it is port 80 instead of 25. You will rely completely on the application itself to enforce whatever security restrictions.
Chances are that some SOAP applications will be browser plugins. But this is an opportunity for every SOAP service provider to lock you in to their proprietary interpreter, displayer, whatever; and believe me, they will.
except that if we can use port filtering primarily, it reduces the amount of work by orders of magnitude
SOAP bypasses security on the client-side. The host running the SOAP server knows the inherent risks. The same as running any network available service. What soap does is run a server process on the client's machine that attempts to bypass any firewall as well as allowing executable code to be run on the client.
i don't allow CGIs or servlets exposed to the world to run on my client machines.
if you use soap, you will