Few cleanups and couple of new things:
- add SHA2 algorithm to older OpenSSL
- add BIGNUM math to have public-key cryptography work on non-OpenSSL
build.
- gen_random_bytes() function
The status of SHA2 algoritms and public-key encryption can now be
changed to 'always available.'
That makes pgcrypto functionally complete and unless there will be new
editions of AES, SHA2 or OpenPGP standards, there is no major changes
planned.
the pubkey functions a bit. The actual RSA-specific code
there is tiny, most of the patch consists of reorg of the
pubkey code, as lots of it was written as elgamal-only.
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The SHLIB section was copy-pasted from somewhere and contains
several unnecessary libs. This cleans it up a bit.
-lcrypt
we don't use system crypt()
-lssl, -lssleay32
no SSL here
-lz in win32 section
already added on previous line
-ldes
The chance anybody has it is pretty low.
And the chance pgcrypto works with it is even lower.
Also trim the win32 section.
---------------------------------------------------------------------------
It is already disabled in Makefile, remove code too.
---------------------------------------------------------------------------
I was bit hasty making the random exponent 'k' a prime. Further researh
shows that Elgamal encryption has no specific needs in respect to k,
any random number is fine.
It is bit different for signing, there it needs to be 'relatively prime'
to p - 1, that means GCD(k, p-1) == 1, which is also a lot lighter than
full primality. As we don't do signing, this can be ignored.
This brings major speedup to Elgamal encryption.
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o pgp_mpi_free: Accept NULLs
o pgp_mpi_cksum: result should be 16bit
o Remove function name from error messages - to be similar to other
SQL functions, and it does not match anyway the called function
o remove couple junk lines
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o Support for RSA encryption
o Big reorg to better separate generic and algorithm-specific code.
o Regression tests for RSA.
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o Tom stuck a CVS id into file. I doubt the usefulness of it,
but if it needs to be in the file then rather at the end.
Also tag it as comment for asciidoc.
o Mention bytea vs. text difference
o Couple clarifications
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There is a choice whether to update it with pgp functions or
remove it. I decided to remove it, updating is pointless.
I've tried to keep the core of pgcrypto relatively independent
from main PostgreSQL, to make it easy to use externally if needed,
and that is good. Eg. that made development of PGP functions much
nicer.
But I have no plans to release it as generic library, so keeping such
doc
up-to-date is waste of time. If anyone is interested in using it in
other products, he can probably bother to read the source too.
Commented source is another thing - I'll try to make another pass
over code to see if there is anything non-obvious that would need
more comments.
---------------------------------------------------------------------------
Marko Kreen
of password-based encryption from RFC2440 (OpenPGP).
The goal of this code is to be more featureful encryption solution
than current encrypt(), which only functionality is running cipher
over data.
Compared to encrypt(), pgp_encrypt() does following:
* It uses the equvialent of random Inital Vector to get cipher
into random state before it processes user data
* Stores SHA-1 of the data into result so any modification
will be detected.
* Remembers if data was text or binary - thus it can decrypt
to/from text data. This was a major nuisance for encrypt().
* Stores info about used algorithms with result, so user needs
not remember them - more user friendly!
* Uses String2Key algorithms (similar to crypt()) with random salt
to generate full-length binary key to be used for encrypting.
* Uses standard format for data - you can feed it to GnuPG, if needed.
Optional features (off by default):
* Can use separate session key - user data will be encrypted
with totally random key, which will be encrypted with S2K
generated key and attached to result.
* Data compression with zlib.
* Can convert between CRLF<->LF line-endings - to get fully
RFC2440-compliant behaviour. This is off by default as
pgcrypto does not know the line-endings of user data.
Interface is simple:
pgp_encrypt(data text, key text) returns bytea
pgp_decrypt(data text, key text) returns text
pgp_encrypt_bytea(data bytea, key text) returns bytea
pgp_decrypt_bytea(data bytea, key text) returns bytea
To change parameters (cipher, compression, mdc):
pgp_encrypt(data text, key text, parms text) returns bytea
pgp_decrypt(data text, key text, parms text) returns text
pgp_encrypt_bytea(data bytea, key text, parms text) returns bytea
pgp_decrypt_bytea(data bytea, key text, parms text) returns bytea
Parameter names I lifted from gpg:
pgp_encrypt('message', 'key', 'compress-algo=1,cipher-algo=aes256')
For text data, pgp_encrypt simply encrypts the PostgreSQL internal data.
This maps to RFC2440 data type 't' - 'extenally specified encoding'.
But this may cause problems if data is dumped and reloaded into database
which as different internal encoding. My next goal is to implement data
type 'u' - which means data is in UTF-8 encoding by converting internal
encoding to UTF-8 and back. And there wont be any compatibility
problems with current code, I think its ok to submit this without UTF-8
encoding by converting internal encoding to UTF-8 and back. And there
wont be any compatibility problems with current code, I think its ok to
submit this without UTF-8 support.
Here is v4 of PGP encrypt. This depends on previously sent
Fortuna-patch, as it uses the px_add_entropy function.
- New function: pgp_key_id() for finding key id's.
- Add SHA1 of user data and key into RNG pools. We need to get
randomness from somewhere, and it is in user best interests
to contribute.
- Regenerate pgp-armor test for SQL_ASCII database.
- Cleanup the key handling so that the pubkey support is less
hackish.
Marko Kreen
* openssl.c: Add 3des and AES support
* README.pgcrypto: list only supported ciphers for openssl
OpenSSL has pre-processor symbol OPENSSL_NO_AES, which
isn't that helpful for detecting if it _does_ exist.
Thus the hack with AES_ENCRYPT.
Marko Kreen
libmcrypt seems to dead, maintainer address bounces,
and cast-128 fails on 2 of the 3 test vectors from RFC2144.
So I see no reason to keep around stuff I don't trust
anymore.
Support for several crypto libraries is probably only
confusing to users, although it was good for initial
developing - it helped to find hidden assumptions and
forced me to create regression tests for all functionality.
Marko Kreen
Converted pgcrypto one too.
* Changed default randomness source to libc random()
That way pgcrypto does not have any external dependencies
and should work everywhere.
* Re-enabled pgcrypto build in contrib/makefile
* contrib/README update - there is more stuff than
only 'hash functions'
* Noted the libc random fact in README.pgcrypto
Marko Kreen
salt generation code. He also urged using better random source
and making possible to choose using bcrypt and xdes rounds more
easily. So, here's patch:
* For all salt generation, use Solar Designer's own code. This
is mostly due fact that his code is more fit for get_random_bytes()
style interface.
* New function: gen_salt(type, rounds). This lets specify iteration
count for algorithm.
* random.c: px_get_random_bytes() function.
Supported randomness soure: /dev/urandom, OpenSSL PRNG, libc random()
Default: /dev/urandom.
* Draft description of C API for pgcrypto functions.
New files: API, crypt-gensalt.c, random.c
Marko Kreen
* remove support for encode() as it is in main tree now
* remove krb5.c
* new 'PX library' architecture
* remove BSD license from my code to let the general
PostgreSQL one to apply
* md5, sha1: ANSIfy, use const where appropriate
* various other formatting and clarity changes
* hmac()
* UN*X-like crypt() - system or internal crypt
* Internal crypt: DES, Extended DES, MD5, Blowfish
crypt-des.c, crypt-md5.c from FreeBSD
crypt-blowfish.c from Solar Designer
* gen_salt() for crypt() - Blowfish, MD5, DES, Extended DES
* encrypt(), decrypt(), encrypt_iv(), decrypt_iv()
* Cipher support in mhash.c, openssl.c
* internal: Blowfish, Rijndael-128 ciphers
* blf.[ch], rijndael.[ch] from OpenBSD
* there will be generated file rijndael-tbl.inc.
Marko Kreen
timing, I know :)) At the moment the digest() function returns
hexadecimal coded hash, but I want it to return pure binary. I
have also included functions encode() and decode() which support
'base64' and 'hex' encodings, so if anyone needs digest() in hex
he can do encode(digest(...), 'hex').
Main reason for it is "to do one thing and do it well" :)
Another reason is if someone needs really lot of digesting, in
the end he wants to store the binary not the hexadecimal result.
It is really silly to convert it to hex then back to binary
again. As I said if someone needs hex he can get it.
Well, and the real reason that I am doing encrypt()/decrypt()
functions and _they_ return binary. For testing I like to see
it in hex occasionally, but it is really wrong to let them
return hex. Only now it caught my eye that hex-coding in
digest() is wrong. When doing digest() I thought about 'common
case' but hacking with psql is probably _not_ the common case :)
Marko Kreen
