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Cryptography in the Database
Ben Rothke writes "Noted security guru Marcus Ranum has observed that "these days, with the kind of plug-ins that come in your typical browser, combined with all the bizarre undocumented protocols used by new Internet applications; makes it highly unlikely that a firewall is doing anything more complex than a thin layer of policy atop routing. As such, the applications behind the firewall are now more critical to security than the firewall itself. Which should scare the holey moley out of you."" Read on for Ben's review.
Cryptography in the Database : The Last Line of Defense
author
Kevin Kenan
pages
312
publisher
Addison-Wesley
rating
9
reviewer
Ben Rothke
ISBN
0321320735
summary
Excellent reference for those that are serious about securing their corporate databases
Taking Ranum's observation to the next level, it is not only the applications that need to be secured, but databases also. The theme of Cryptography in the Database - The Last Line of Defense is that databases, being the main repository for critical consumer and business data, are often not given the adequate level of security that they deserve.
Large databases often contain terabytes of data. This data often contains R&D, client, customer data and more, that if compromised, could wreak havoc on an organization; both from a public relations perspective, in addition to a regulatory perspective. In a large customer driven organization, a database breach can wreak havoc on tens of thousands of customer records. With all of that, companies will spend large amounts of money on the security appliance of the month, but often let their databases sit unprotected.
Cryptography in the Database is a valuable book in that it shows how a formal methodology is required to adequately protect large corporate databases. The emphasis of the book is on designing and integrating a cryptosystem into the database to protect it against the various threats that are specifically launched against corporate database systems.
The books 4 parts contain 21 chapters. Part one is brief overview of the need for database security, along with related threats to database, and also covers the basic concepts of cryptography and encryption.
Part two provides a comprehensive synopsis on the cryptographic infrastructure necessary to secure corporate databases. Chapter 3 goes into details on how to set up an effective key management scheme. Such a scheme is crucial as the author notes that all it takes is the loss of a single 128-bit key, and gigabytes of data can become inaccessible.
Part two also creates a sample cryptographic architecture that is flexible and modular so that it is easily adaptable to various situations. The author notes that such systems can be difficult to manage if they become overly complex, and the challenge is to find the right balance between security and complexity on one side, and usability on the other. Creating an effective cryptographic database infrastructure. is not an elementary task given the different requirements of security and functionality.
Chapter 3 details the various entities that go into a complete cryptographic architecture, including the cryptographic engine, and the various controls around the crypto keys. The chapter provides a good overview of the key life cycle. Historically, controls around the key life cycle are crucial. One of the ways the Allies were able to break the German Enigma cipher machine during World War II was that the German's reused their crypto keys, which obviates much of the security that cryptography can provide. Had the German's not done that, the outcome of the war may have been dramatically different.
Part 3 details the issues that need to go into the entire cryptography project. Kenan notes that for security to be effective, it must be dealt with at the commencement of a project and must permeate the overall design and seep into every line of code. Also, in the long term, developing a culture of security depends on looking at security as an opportunity to provide extra value. Where security fails is when it is viewed merely as a series of checklists that are meant to get in the way.
Chapter 9 shows how data flow diagrams can be used by a database analyst to better understand how a system works. These data flow diagrams are valuable as that they show the various inputs into the system and where potential failures can crop up.
Part 4 provides various Java code examples of the cryptographic infrastructure that were detailed in the previous 12 chapters. The example code is meant to show how to implement the primary functionality of the various components that the book describes.
One of the popular terms in security today is data at rest, which refers to all data in storage. Businesses, government agencies, and others need to deal with attacks on data at rest, which more often then not will be found on databases.
After reading Cryptography in the Database, the reader can understand why database cryptography must be implemented in a methodological fashion, since incorrectly implemented cryptography can often be worse than no cryptography at all. With that, database administrators, architects and others who have input into the design of database security are highly advised to read Cryptography in the Database.
Databases are far too critical to an organization to be left unsecured, or incorrectly secured. The database is indeed the last line of defense in an organization. Books such as this are thusly vital to ensure that the last line of defense is not easily breached.
You can purchase Cryptography in the Database from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Taking Ranum's observation to the next level, it is not only the applications that need to be secured, but databases also. The theme of Cryptography in the Database - The Last Line of Defense is that databases, being the main repository for critical consumer and business data, are often not given the adequate level of security that they deserve.
Large databases often contain terabytes of data. This data often contains R&D, client, customer data and more, that if compromised, could wreak havoc on an organization; both from a public relations perspective, in addition to a regulatory perspective. In a large customer driven organization, a database breach can wreak havoc on tens of thousands of customer records. With all of that, companies will spend large amounts of money on the security appliance of the month, but often let their databases sit unprotected.
Cryptography in the Database is a valuable book in that it shows how a formal methodology is required to adequately protect large corporate databases. The emphasis of the book is on designing and integrating a cryptosystem into the database to protect it against the various threats that are specifically launched against corporate database systems.
The books 4 parts contain 21 chapters. Part one is brief overview of the need for database security, along with related threats to database, and also covers the basic concepts of cryptography and encryption.
Part two provides a comprehensive synopsis on the cryptographic infrastructure necessary to secure corporate databases. Chapter 3 goes into details on how to set up an effective key management scheme. Such a scheme is crucial as the author notes that all it takes is the loss of a single 128-bit key, and gigabytes of data can become inaccessible.
Part two also creates a sample cryptographic architecture that is flexible and modular so that it is easily adaptable to various situations. The author notes that such systems can be difficult to manage if they become overly complex, and the challenge is to find the right balance between security and complexity on one side, and usability on the other. Creating an effective cryptographic database infrastructure. is not an elementary task given the different requirements of security and functionality.
Chapter 3 details the various entities that go into a complete cryptographic architecture, including the cryptographic engine, and the various controls around the crypto keys. The chapter provides a good overview of the key life cycle. Historically, controls around the key life cycle are crucial. One of the ways the Allies were able to break the German Enigma cipher machine during World War II was that the German's reused their crypto keys, which obviates much of the security that cryptography can provide. Had the German's not done that, the outcome of the war may have been dramatically different.
Part 3 details the issues that need to go into the entire cryptography project. Kenan notes that for security to be effective, it must be dealt with at the commencement of a project and must permeate the overall design and seep into every line of code. Also, in the long term, developing a culture of security depends on looking at security as an opportunity to provide extra value. Where security fails is when it is viewed merely as a series of checklists that are meant to get in the way.
Chapter 9 shows how data flow diagrams can be used by a database analyst to better understand how a system works. These data flow diagrams are valuable as that they show the various inputs into the system and where potential failures can crop up.
Part 4 provides various Java code examples of the cryptographic infrastructure that were detailed in the previous 12 chapters. The example code is meant to show how to implement the primary functionality of the various components that the book describes.
One of the popular terms in security today is data at rest, which refers to all data in storage. Businesses, government agencies, and others need to deal with attacks on data at rest, which more often then not will be found on databases.
After reading Cryptography in the Database, the reader can understand why database cryptography must be implemented in a methodological fashion, since incorrectly implemented cryptography can often be worse than no cryptography at all. With that, database administrators, architects and others who have input into the design of database security are highly advised to read Cryptography in the Database.
Databases are far too critical to an organization to be left unsecured, or incorrectly secured. The database is indeed the last line of defense in an organization. Books such as this are thusly vital to ensure that the last line of defense is not easily breached.
You can purchase Cryptography in the Database from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
I think most companies know the importance of security on firewall, server, application and database, but trying to get a budget for such measures is another matter.
So maybe to most companies, extreme-security is a gamble they are willing to take, or they simply don't value customer data as much as customers do.
We have seen so many cases of stolen university data, or even credit card details, but when have we heard a Press Release saying "no worries, the data is crypto-protected with this how-many-bit technology".
Rock that crushes, Paper & Scissors that don't matter.
I can't tell you how many times I've seen apps all using the same credentials to log into the database... The ID and password are hardcoded into the app, and it's the same for all the vendor's customers. And no, these aren't little one-off apps for small businesses, these are enterprise apps. I've also taken advantage of this fact for pen testing....
Isn't this exactly the kind of security that Reiser4 wants to address via its plugins system, while also adding more speed to the filesystems?
If I clone myself, can I call it a thread?
If a girl winks to us, can I call it a race condition?
I have certain programs on my computer that can get past my firewall for various reasons. I often wonder about some of the biggest heists in the world, they're usually done by someone on the inside. If your network is locked down and something from the inside punches a hole in it how do you control any of that?
Generation Trance: What generation are you?
At least in California, the data compromise notification law makes a specific exception for encrypted data (which is usually on backup tapes).
It may be just me, but I honestly have to question whether someone can really be a "security guru" when they tell me that something should "scare the holey moley" out of me (or anyone, for that matter). That kind of sensationalism just leads to blind panics and failed attempts at security that actually makes thing less secure than they originally were.
What's more, someone who actually knows something about security (whether it's computer security or not) should not have to resort to that kind of attention-whoring, anyway - so if someone still does, it also makes me wonder just how competent they really are.
quidquid latine dictum sit altum videtur.
The larger point of database security measures notwithstanding, I think the days of the "dumb" application-blind firewall are over.
Most companies that handle credit cards in modest amounts are required by their providers to use application-aware systems like Teros, which inspect every detail of every transaction across the border at the highest levels - providing a redundant check in the form of a policy controlling things like what cookies and querystring values can accompany a request for a particular path, and looking for things like cookies appearing that you didn't set, or form values being submitted that weren't in the HTML form you sent out...
Tired of Political Trolls? Opt Out!
since the apps are too simple and encryption is needed on all layers, I do expect a book like the one in the subject. ONLY the persons allowed (with special glasses) will be able to understand the warped rays of light coming from the monitor, for everybody else will look like BSOD...
hey, you heard it here first
I had another sig before, but this one is better
The only way to convince companies to spend the money to protect consumer data is to make it more expensive for the company not to implement basic safety features by punishing companies monetarily for loss of consumer data such as social security numbers and birth dates on a per consumer or record basis. Other consumer information such as name/telephone number is obviously not as critical and should not be subject to monetary fines/punishment. Every company that stores SS#s or Drivers License or Passport numbers would then have a financial motivation to do everything possible to protect critical consumer information or not use/store it at all. Given all the national security issues, this should be easy to justify since identity theft was identified by the Administration as a national security threat. As for protecting the company's own information, it should be pretty easy to show the cost of losing the data versus the cost of implementing a security feature. If you notify your boss in writing of the consequences, then if data is breached, he/she will be accountable.
On the new Battlestar Galactica, the rule is you don't connect critical computers to other computers. This limits the damage the bad guys can do.
There was that one episode....
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
The problem with data security on an open network is not the lack of adequate technology or know-how because current methods of securing computers do work. Otherwise, our electronic commerce systems would have collapsed years ago. The problem is that hackers look for and often find ways of getting around the security barriers by exploiting defects in the underlying software. A network's security is thus intimately tied to the reliability and robustness of the network's software. Security companies have no way of guaranteeing that the various software modules used in their systems are defect-free. This uncertainty is the Achilles' heel of the security industry. The solution is to move away from algorithmic software and adopt a non-algorithmic, signal-based, synchronous software model.
Point of fact, you don't implement crypto yourself. That is the most horrid mis take that anyone can make. Let the security professionals implement it, and just use it. They are far more paranoid that you are and are far better to do this specialised way of coding.
Security is a feild in which you must have a good level of mastery of many different areas otherwise you are a liability. If you don't got that, then don't implement a system. Use one that someone else has written.
IMO, this book will make too many people think that they are good enough to do what they can't do. I can only imagine how many insecure system will be developed because of it.
Sorry, but it needn't be that hard to do, given the right tools; the author is really scaring off the troops fm even attempting it.
You need to design against what's widely accepted as the most usual scenario, intrusion by an insider. Requirements shd include not less than the following:
Protect against data visibility even in the worst case, a massive physical compromise of the entire database.
Compromised access to any single record must not lead directly to compromised access to any other record.
I did field-level encryption against these requirements at a major federal agency, and the result got blessed by the security troops there.
What I've seen happen is that there's two different cultures working here: When you ask the application guys what they're doing re database security/encryption, they'll too often reply " It's a network problem, so go talk to those guys. " Ask the network guys what they're doing re the same thing, they'll too often reply " That's an application problem, so go talk to the application troops. "This hurdle needs to be cleared if there's any hope for progress.
1) Use your firewall to block everything except port 80.
2) Invent a generic TCP/IP tunneling protocol over HTTP (like SOAP); call it TP.
3) Tunnel all your network traffic through TP.
4) Problem solved!
The beauty of this system is that you can run TP over TP as many times as you wish, adding as many layers of security as you feel necessary to keep you from shitting your pants over the big bad hackers who are pwnz0ring j00r data.
There must be a master key somewhere, so the database itself can see all the unencrypted data. If not, then indexes are meaningless as the fields to be indexed would be gibberish and not subject to any form of ordering. Database performance would tank and large systems would be unusable.
This master key must then be highly guarded. If it is kept on the machine, it is subject to pillage just like any other compromised machine and the encryption does no good. If it isn't, then whenever the database service is restarted the key must be fetched.
The current forms of database protections -- views & user rights -- limit the data available to the various users. These are usually not properly implemented and can provide a great deal of protection in shared databases.
-Charles
Learning HOW to think is more important than learning WHAT to think.
Firewalls have become largely irrelevant because they stop people from doing things, so people specifically design applications to easily pierce a firewall!
Thus, the firewall becomes less and less relevant with time.
Originally, the great designers of IP gave us any number of protocols, and 65,534 ports in each protocol. Different applications could use different ports, and these ports would identify what application you wanted to connect to. Port 80 was used for web traffic, Email uses port 25. This gives incredible room for growth and expansion, and was "a good design". (TM)
Firewalls block all but ports 80, 25, 443, and maybe a few others. Thus, many applications are now built using ONLY one of these ports!
So now, we have the dog, the kitchen sink, Instant Messaging, RSS, XML/RPC, and god knows what else tunnelled over port 80. Dude, Like where's my firewall?
So, push comes to shove, there are no real shortcuts without a long term price.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
First you need to allow more then just http through the 2nd firewall since it needs database access...
Second, firewalls really don't do that much for you. They stop things like blaster which attack an open port on the operating system, but let's fix the damn oeprating system to patch those holes, not just cover them up with a rug.
You don't really have to "hack through" a firewall. The hack is you leaving any ports open. If I can get through http, that's all I need. The real protection should be that all incomming and outgoing traffic from http will not harm your system in any possible way.
It looks like the main purpose of crypting your personal data in a database is so that people that have access to the database cannot read the information in plain text. If you're using Oracle, you can put permissions on each of the individual columns to mimic the same results crypting your database would produce. These people are really just worried about their data readers opening a sql client and just extracting information, kind of like how you're luggage goes through an airplane. We'd like to think that the workers there won't steal anything out of our luggage, but we sure as hell won't put our luggage through without a lock on it at least.
Security to me is a huge deal, but beyond my application level security and the permissions I put on the data, most other things are out of my control. The solutions people propose do nothing but delay me in my work that I should be doing instead.
I'd rather push all of this burden to the people that can really make the difference in this field. The manufacturer's of the software that run our systems (os) and the servers (apache/mysql/ms*/etc.), you make those secure, and we won't have to be this damn paranoid.
Secure software is not impossible.
The fact is that most database engines (the entire database application) come with a fairly good security model that almost never gets implemented. There is typically very little done to most databases in the way of restricting user accounts to specific databases (not instances of the engine), tables, rows, columns, etc. One of the biggest lessons in this ought to come from the sheer number of SQL worms out there that look for instaces that don't have a SQL admin password set - DUH! The fact that these are still being issued means that DBA's still have not wised up enough to even set the password. If your security model is so lax that you can't be bothered to either set a password or change the factory default, you're not going to be concerned with minor details like patching your operating system and application, doing any kind of hardening, or setting appropriate access permissions.
The fact of the matter is that until more mandatory disclosure laws are passed companies will simply choose to ignore the simple basic things they can do to secure a database. Security to many (PHB) managers is a widget of some kind that they can buy and plug in to their network. This writer ignores a very simple flaw in his logic. Typcially, one compromises the database to get the box. If I own the box, encrypting the contents of the datbase won't help you any. It's going to have to be encrypted in such a way that it can be decrypted for use, unless you plan on turning all your data into MD5 hashes (evil grin).
Given the assumption that you want to be able to decrypt your data, you'll have to have the means to do so either stored on that box or on the receiving box, which is also likely on your network. If it's stored on that box, guess what, I've got access to it since UR ()WN3D. If it's another box, hey, I got this one so I can see what this one answers requests from and then I know what I need to ()WN next. Since your security on box was obviously lax enough to let me in, getting the next box down the line won't be any harder.
Mind you that all this assuming that I don't fire up the Beowulf cluster and just crack your encryption the hard way.
2 cents,
Queen B
HDGary secures my bank
You can't just encrypt your data and share keys. If you do, then the compromise of a key provides access to that data. If someone hacks into your network, maybe that key will be found somewhere on a system that they compromise. Then, they can actually evesdrop on the database connections and pull data as it is being sent across the wire without authenticating.
A better solution (and one that PostgreSQL uses) is to use SSL to secure the connection and thus encrypt the traffic to and from the server. Yes, if you compromise the database server, you get the data anyway, but in the other approach, if you compromise the key management server, you might get far more than the data. Note that PostgreSQL also supports client-side certificates which, while not perfect, provide an added layer of security (cient-side SSL is a host authentication mechanism, not a user authentication mechanism so normal login requirements still apply-- basically now you have 2-factor authentication).
The second vital area is that of access control. Encrypting your data doesn't do you any good if you don't adequately lock down access. Shared database accounts? No. Use one account per *user* and use groups/roles for access control.
Finally, encrypting some data in the database might be required by some applications (for example, if you store credit card transactions in your database so you can later reverse a charge, the PCI-DSS requires that the number is encrypted in storage). But encrypting most data will simply prevent your relational model from working properly.
LedgerSMB: Open source Accounting/ERP
... but it sure is now, and here's two giant reasons why:
HIPAA
PCIDSS
Both specify, more or less, that sensitive information must be encrypted within the database. That means the data at rest on disk must be encrypted. Encrypting customer-sensitive information in the database will prevent exposure of customer sensitive information from:
Disk-scraping attacks (such as if the storage rep who replaces a failed drive in the SAN is ethically challenged)
Backup attacks (where a complete database backup can be restored and hacked)
What doesn't it save you from?
Users who have rights they don't need looking at data they don't need.
Users who don't need access to the system but have it anyway.
Poor security standards (not changing default passwords, insufficient password strength, etc).
The DBA, who can always log in and see whatever the heck he wants(I almost said he or she, but who am I kidding).
The SysAdmin, who can become the DBA, and can scrape the disks himself.
What are the costs of encryption?
1. It will cost you CPU cycles. (Don't even think about sending all the crypto calls over the wire to a hardware module -- it'll cut application througput in half).
2. You won't be able to have queries like "Select name from patients where ssn between '5030000000' and '503999999'" use indexes, as the ordering of crypto is gone forever.
What's being done about this?
Enterprise vendors are busy rolling out encryption solutions (the other security holes already have support around them, but often aren't implemented in applications.) DB2 lets you encrypt the file system, or tables, or values within tables.
Oracle lets you encrypt columns within tables with AES128, AES192, AES256, or 3DES. (You can also set it up so that the same value in 2 columns has the same ciphertext, which is a good thing.)
SQL Server's got... something, but I don't support it, so I don't care.
(PostgreSQL and MySQL users, I left you out on purpose. I said enterprise vendors, and I meant it.)
That's why application layer firewalls are such a big deal. They are supposed to understand what data and more importantly what kind of data specific apps from both sides are supposed to be generating and filter at that level. They can be a royal pain to design and keep running. With custom apps, however, it's a whole different story.
One of the great concepts I learned at my last training was the idea of compartmentalization. This is after many other layers of defense, but the idea is even if you are compromised, they get nothing of real value.
There also many, many other ways to add protection: gambits, exclusion, audit-traps, active detection, etc.
Like the author, one of my big concerns is with poorly written apps. Anytime anything is specifically designed to release data but has restrictions on who gets what and how, you have a security concern. I have seen companies go to such extremes as pushing data to the screen as one big jpeg to keep from anything grabbing said data (of course, there are tools that can grab visual data from graphics just like humans now). My biggest concern is the original and still number one concern of all types of security: corruption from within. Be it sabotage, espionage, or unintentional damage (virus) the equipment and personnel inside an organisation is always more dangerous than those outside it.
And that's when manageing your information through compartmentalization and multilayer defense, etc. come in. You may get in systems, but you are not getting anything of real value and you aren't getting out again.
[RIAA] says its concern is artists. That's true, in just the sense that a cattle rancher is concerned about its cattle.
You know, where you _review_ the book? As in whether the book is high-quality, or not. As in whether the author is a good writer, or not. As in whether the contents are relevant, or not. As in whether I should buy the book rather than some other book.
Instead, we get a synopsis of what the book covers, plus a blurb for why the topic is important. Yes, securing databases is important! Yes, Part 4 provides Java examples! But why do I want to buy THIS book about securing databases? Why do I want to buy THIS book with Java examples?
They should have some sort of guidelines to follow. They could call them "Slashdot Book Review Guidelines". The guidelines could include points like "Is the book readable as well as technically accurate?" and "How gracefully do you expect the content to age?" That would be amazing.
Even if data transfer is one way you still need the other way because of how TCP/IP works with acknowledgements and retransmit requests. Your idea of removing wires would break all network communication.
Granted, hard-coding those values is pretty absurd, but the single login does make sense, mostly financial, but in a very, very non-trivial way.
When you're sold an enterprise server for an enterprise app with a $1250 per-seat (much less named users) fee and you have 5,000 concurrent users, that's $6.25 million. You can buy the same server with five or ten user licenses for $40k. Provided the application is secure enough, the cost v. benefit of having per seat licenses just doesn't pan out. Cut another way, fine, you have named users passing through to the database and those logins come through the application. Does that _really_ make you much more secure if those logins can be compromised? Sure, you might sniff out the lowliest account, but if you can do that, you can sniff out the admin account as well. Where's the $6M advantage? I'm seeing a subtle variant of security-via-obscurity here. "Gosh, if they have to pick from thousands of accounts instead of dozens, we're secure!" Right.
Case in point: The state of California was sold a named user license by Oracle for $1.5 BILLION. That's right, name every goddamned user working on the State of California network. Not really much different than a per-seat license, but I suppose they could have saved, say, a billion, leaving them with a $500,000,000 database license. I believe the purchase orders -- and the careers of those who signed them -- were cancelled prior to payment.
So, where do you draw the line on this nonsense? 100 users? 1,000? 10,000? Does it really make a difference? If you can hack 1:100, what's the value of reducing it to 1:10,000?
This seems like a very odd quote to use to introduce this book, because one of the things Ranum seems to be talking about is that use of encryption and complex protocols can make security worse.
Why worse? Because the firewall, mainstay of our security efforts, becomes less and less effective. In the old days, your firewall could give a fairly cursory glance at packet headers, and have a good shot at catching the bad ones. Now, the packet header isn't so useful, because there is complex stuff inside the packet --- protocols are layered three deep or more.
That's why we need security at the application layer, instead of at the network transport layer --- the network transport layer just doesn't "know" enough to catch threats. What makes this really scary is that there is less of a bottleneck for the threats. It's nice as a defender to have a bottleneck you can protect. If the bottleneck goes away, and you have to protect all the applications, that's pretty scary.
Cryptography isn't going to give us a lot of help here, IMO. Yes, when our security has been breached, it can give a second line of defense, but that's about all (and even that seems a little suspect in a world with keystroke loggers).
HIPAA [specifies], more or less, that sensitive information must be encrypted within the database. That means the data at rest on disk must be encrypted.
That's not actually the case when it comes to HIPAA. Encryption is not a required element of the technical safeguards for data, it's only an addressable element. See section 164.312 part (a)(2)(iv) of the final Security Rule, which can be found in the Federal Register (volume 68 number 34 page 8378) or on my desk.
The regulation requires the covered entity to implement appropriate administrative, physical, and technical safeguards for protected health information. Encryption is just one element of those safeguards, and an optional one at that. Remember that HIPAA views security as including not only confidentiality, but also integrity and availablility of data. Encrypting data at rest would often be a marginal improvement to confidentiality at a potentially large risk to availablility (or even integrity). It may be a good idea in some security environments, of course, but encryption is not a blanket requirement of HIPAA.
(Even data in transit does not require encryption under HIPAA. It simply requires protection commensurate with the risk. Protected health information transmitted over a dialup line probably does not need encryption, whereas any transmission containing PHI over the internet certainly does need encryption.)
The attacks you suggest solving by database encryption can also be dealt with by policies regarding media disposal and backup media safeguards. A HIPAA covered entity is required to have a media disposal policy anyway, and offsite backup tapes are just another form of data in transit to be protected accordingly. Database encryption may be a valuable additional layer, but it's certainly not the only way to skin that cat.
(Incidentally, about half the Oracle DBAs at my EMR vendor are women.)
With reasonable men I will reason; with humane men I will plead; but to tyrants I will give no quarter. -- William Lloyd