OpenSSL-3.+ how to configure [random]?

[Dr Paul Dale]

Currently I've no idea and can't reproduce locally :(

A rogue configuration file could cause the DRBGs/seeds to fail.  Do you 
have seed=rdrand line in the random section?  That will cause the 
seeding source to fail to load at all.


Pauli

On 10/11/21 1:10 pm, Blumenthal, Uri - 0553 - MITLL wrote:
> Thank you!
>
> I'm trying to:
>
> a. understand why something like "openssl-3 rand -hex 4" does not work (returns empty string), but "openssl-3 rand -engine rdrand -hex 4" works fine, and gives me my random bytes - here's an illustration
>
> $ openssl3 version
> OpenSSL 3.1.0-dev  (Library: OpenSSL 3.1.0-dev )
> $ openssl3 info -seeds
> rdrand ( rdseed rdrand ) os-specific
> $ openssl3 rand -hex 4
> $ openssl3 rand -engine rdrand -hex 4
> Engine "rdrand" set.
> d9b8f268
>
> and
>
> b. somehow force RDRAND engine to be loaded and initialized by default, so I don't have to include "-engine rdrand" in every invocation, especially since I often need to specify other engines (like "pkcs11").
>
> Here's my config, in case you spot something wrong with it (and yes, it includes "rdcpu"):
>
> ./config --prefix=${OPENSSL_DIR} --debug --openssldir=${OPENSSL_DIR}/etc --with-rand-seed=rdcpu,os enable-ec_nistp_64_gcc_128 enable-md2 enable-rc5 enable-rmd160 enable-weak-ssl-ciphers zlib-dynamic enable-ssl-trace enable-trace threads enable-buildtest-c++
>
> Thanks
> --
> Regards,
> Uri
>   
> There are two ways to design a system. One is to make is so simple there are obviously no deficiencies.
> The other is to make it so complex there are no obvious deficiencies.
>                                                                                                                                       -  C. A. R. Hoare
>   
>
> On 11/9/21, 21:49, "openssl-users on behalf of Dr Paul Dale" <openssl-users-bounces at openssl.org on behalf of pauli at openssl.org> wrote:
>
>      Currently there is exactly one seed source that is usable in OpenSSL
>      3.0: "SEED-SRC".  It is documented in EVP_RAND-SEED-SRC.  The reason the
>      seed source can be set is to allow you to use a third party provider
>      than includes one.
>
>      If you want to force RDRAND as the only seeding source, this needs to be
>      done at configuration time with the --with-rand-seed configuration
>      option.  Note that this will enable RDSEED in preference to RDRAND but
>      will use RDRAND if RDSEED isn't available.
>
>      I assume that you meant openssl info -seeds not openssl list -seeds.
>      This lists the seed sources that were configured at build time.
>
>
>      There is no relationship between the RDRAND engine and the seed
>      sources.  Well, they both use the same machine instruction to get the
>      seed material but it's called from completely different places.
>
>
>      Yes, the man pages could be more informative and user friendly :(
>
>
>      Pauli
>
>      On 10/11/21 12:35 pm, Blumenthal, Uri - 0553 - MITLL wrote:
>      > "man config" for OpenSSL-3.0 and newer says that there can be "[random]" section in "openssl.cnf", where I can specify type of RNG, other things, and *seed*, and seed *properties*.
>      >
>      > Unfortunately, it did not bother to even list the possible/allowed values, let alone explain what they'd mean:
>      >
>      >     Random Configuration
>      >         The name random in the initialization section names the section containing the random number
>      >         generater settings.
>      >
>      >         Within the random section, the following names have meaning:
>      >
>      >         random
>      >             This is used to specify the random bit generator.  For example:
>      >
>      >              [random]
>      >              random = CTR-DRBG
>      >
>      >             The available random bit generators are:
>      >
>      >             CTR-DRBG
>      >             HASH-DRBG
>      >             HMAC-DRBG
>      > .  .  .  .  .
>      >         properties
>      >             This sets the property query used when fetching the random bit generator and any
>      >             underlying algorithms.
>      >
>      >         seed
>      >             This sets the randomness source that should be used.  By default SEED-SRC will be used
>      >             outside of the FIPS provider.  The FIPS provider uses call backs to access the same
>      >             randomness sources from outside the validated boundary.
>      >
>      >         seed_properties
>      >             This sets the property query used when fetching the randomness source.
>      >
>      > I want to configure this [random] to use CTR-DRBG, using RDRAND as "seed". Based on "openssl list -seeds", I guess "seed = rdrand" should be OK. What properties can I set, if any? How does this "[random]" relate to the RDRAND *engine* (see below)?
>      >
>      > $ openssl3 engine rdrand -t
>      > (rdrand) Intel RDRAND engine
>      >       [ available ]
>      >
>      >
>      > Thanks!
>      > --
>      > Regards,
>      > Uri Blumenthal                              Voice: (781) 981-1638
>      > Secure Resilient Systems and Technologies   Cell:  (339) 223-5363
>      > MIT Lincoln Laboratory
>      > 244 Wood Street, Lexington, MA  02420-9108
>      >
>      > Web:     https://www.ll.mit.edu/biographies/uri-blumenthal
>      > Root CA: https://www.ll.mit.edu/llrca2.pem
>      >
>      > There are two ways to design a system. One is to make is so simple there are obviously no deficiencies.
>      > The other is to make it so complex there are no obvious deficiencies.
>      >                                                                                                                                       -  C. A. R. Hoare
>      >
>