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69 commits

Author SHA1 Message Date
Dr. Matthias St. Pierre
b5acbf9148 Reorganize local header files
Apart from public and internal header files, there is a third type called
local header files, which are located next to source files in the source
directory. Currently, they have different suffixes like

  '*_lcl.h', '*_local.h', or '*_int.h'

This commit changes the different suffixes to '*_local.h' uniformly.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9681)
2019-09-27 23:58:06 +02:00
Dr. Matthias St. Pierre
0c994d54af Reorganize private crypto header files
Currently, there are two different directories which contain internal
header files of libcrypto which are meant to be shared internally:

While header files in 'include/internal' are intended to be shared
between libcrypto and libssl, the files in 'crypto/include/internal'
are intended to be shared inside libcrypto only.

To make things complicated, the include search path is set up in such
a way that the directive #include "internal/file.h" could refer to
a file in either of these two directoroes. This makes it necessary
in some cases to add a '_int.h' suffix to some files to resolve this
ambiguity:

  #include "internal/file.h"      # located in 'include/internal'
  #include "internal/file_int.h"  # located in 'crypto/include/internal'

This commit moves the private crypto headers from

  'crypto/include/internal'  to  'include/crypto'

As a result, the include directives become unambiguous

  #include "internal/file.h"       # located in 'include/internal'
  #include "crypto/file.h"         # located in 'include/crypto'

hence the superfluous '_int.h' suffixes can be stripped.

The files 'store_int.h' and 'store.h' need to be treated specially;
they are joined into a single file.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9681)
2019-09-27 23:57:58 +02:00
Dr. Matthias St. Pierre
1b0fe00e27 drbg: ensure fork-safety without using a pthread_atfork handler
When the new OpenSSL CSPRNG was introduced in version 1.1.1,
it was announced in the release notes that it would be fork-safe,
which the old CSPRNG hadn't been.

The fork-safety was implemented using a fork count, which was
incremented by a pthread_atfork handler. Initially, this handler
was enabled by default. Unfortunately, the default behaviour
had to be changed for other reasons in commit b5319bdbd0, so
the new OpenSSL CSPRNG failed to keep its promise.

This commit restores the fork-safety using a different approach.
It replaces the fork count by a fork id, which coincides with
the process id on UNIX-like operating systems and is zero on other
operating systems. It is used to detect when an automatic reseed
after a fork is necessary.

To prevent a future regression, it also adds a test to verify that
the child reseeds after fork.

CVE-2019-1549

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9802)
2019-09-09 17:09:06 +01:00
Antoine Cœur
a5c83db4ae Fix Typos
CLA: trivial

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/9295)
2019-07-31 19:48:30 +02:00
Bernd Edlinger
e8d866dcb1 Allocate DRBG additional data pool from non-secure memory
The additional data allocates 12K per DRBG instance in the
secure memory, which is not necessary. Also nonces are not
considered secret.

[extended tests]

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/9424)
2019-07-23 23:14:14 +10:00
Richard Levitte
35fd99538a Update copyright year
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9034)
2019-05-28 14:49:38 +02:00
Pauli
e3568508c3 Cosmetic rand/drbg changes.
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/8554)

(cherry picked from commit b3d113ed29)
2019-03-22 16:23:05 +10:00
Dr. Matthias St. Pierre
c39df745b0 Test: link drbgtest statically against libcrypto
and remove duplicate rand_drbg_seedlen() implementation again.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7462)

(cherry picked from commit 1c615e4ce9)
2018-11-08 16:32:30 +01:00
Bernd Edlinger
294941aebb Rename the rand_drbg_st data member "pool" to "seed_pool"
... to make the intended use more clear and differentiate
it from the data member "adin_pool".

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7575)

(cherry picked from commit 31f32abb8e)
2018-11-07 15:23:39 +01:00
Bernd Edlinger
9bc987f008 Initialize reseed_gen_counter to 1, like it is done in master
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7532)
2018-11-07 15:16:19 +01:00
Bernd Edlinger
939ef2ea11 Avoid two memory allocations in each RAND_DRBG_bytes
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7518)
2018-11-05 22:52:24 +01:00
Bernd Edlinger
c40c1ef4f3 Fix error handling in RAND_DRBG_uninstantiate
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7519)
2018-11-05 22:46:21 +01:00
Bernd Edlinger
ee5a79104c Fix error handling in rand_drbg_new
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7519)
2018-11-05 22:46:20 +01:00
Bernd Edlinger
f98a893ed4 Fix error handling in RAND_DRBG_set
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7519)
2018-11-05 22:46:20 +01:00
Bernd Edlinger
faca6bfac3 Fix a race condition in drbg_add
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7523)

(cherry picked from commit 4011bab1f8)
2018-10-30 23:28:12 +01:00
Bernd Edlinger
6101850baf Rework and simplify resource flow in drbg_add
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7504)

(cherry picked from commit f9e43929c4)
2018-10-29 12:31:21 +01:00
Dr. Matthias St. Pierre
d2953e5e7d drbg_lib: avoid NULL pointer dereference in drbg_add
Found by Coverity Scan

Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7511)

(cherry picked from commit 59f90557dd)
2018-10-28 19:21:12 +01:00
Bernd Edlinger
1f98527659 Fix data race in RAND_DRBG_generate
Fixes #7394

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7399)

(cherry picked from commit a83dc59afa)
2018-10-27 13:04:55 +02:00
Dr. Matthias St. Pierre
d597a9a877 RAND_add()/RAND_seed(): fix failure on short input or low entropy
Commit 5b4cb385c1 (#7382) introduced a bug which had the effect
that RAND_add()/RAND_seed() failed for buffer sizes less than
32 bytes. The reason was that now the added random data was used
exlusively as entropy source for reseeding. When the random input
was too short or contained not enough entropy, the DRBG failed
without querying the available entropy sources.

This commit makes drbg_add() act smarter: it checks the entropy
requirements explicitely. If the random input fails this check,
it won't be added as entropy input, but only as additional data.
More precisely, the behaviour depends on whether an os entropy
source was configured (which is the default on most os):

- If an os entropy source is avaible then we declare the buffer
  content as additional data by setting randomness to zero and
  trigger a regular   reseeding.

- If no os entropy source is available, a reseeding will fail
  inevitably. So drbg_add() uses a trick to mix the buffer contents
  into the DRBG state without forcing a reseeding: it generates a
  dummy random byte, using the buffer content as additional data.

Related-to: #7449

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7456)

(cherry picked from commit 8817215d5c)
2018-10-27 13:03:35 +02:00
Dr. Matthias St. Pierre
35a34508ef Backport some DRBG renamings and typo fixes
In commit 8bf3665196 some renamings andd typo fixes were made
while adding back the DRBG-HMAC and DRBG-HASH implementation.
Since the commit could not be backported, a lot of unnecessary
differences between master and 1.1.1 were introduced.

These differences result in tiresome merge conflicts when
cherry-picking. To minimize these merge-conflicts, this patch
ports all 'non-feature' changes of commit 8bf3665196
(e.g., renamings of private variables, fixes of typographical
errors, comment changes) manually back to 1.1.1.

The commits a83dc59afa (#7399) and 8817215d5c (#7456)
failed to cherry-pick previously to 1.1.1, with this patch
they both cherry-pick without conflicts.

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/7505)
2018-10-26 23:04:23 +02:00
Dr. Matthias St. Pierre
dbf0a49625 DRBG: fix reseeding via RAND_add()/RAND_seed() with large input
In pull request #4328 the seeding of the DRBG via RAND_add()/RAND_seed()
was implemented by buffering the data in a random pool where it is
picked up later by the rand_drbg_get_entropy() callback. This buffer
was limited to the size of 4096 bytes.

When a larger input was added via RAND_add() or RAND_seed() to the DRBG,
the reseeding failed, but the error returned by the DRBG was ignored
by the two calling functions, which both don't return an error code.
As a consequence, the data provided by the application was effectively
ignored.

This commit fixes the problem by a more efficient implementation which
does not copy the data in memory and by raising the buffer the size limit
to INT32_MAX (2 gigabytes). This is less than the NIST limit of 2^35 bits
but it was chosen intentionally to avoid platform dependent problems
like integer sizes and/or signed/unsigned conversion.

Additionally, the DRBG is now less permissive on errors: In addition to
pushing a message to the openssl error stack, it enters the error state,
which forces a reinstantiation on next call.

Thanks go to Dr. Falko Strenzke for reporting this issue to the
openssl-security mailing list. After internal discussion the issue
has been categorized as not being security relevant, because the DRBG
reseeds automatically and is fully functional even without additional
randomness provided by the application.

Fixes #7381

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7382)

(cherry picked from commit 3064b55134)
2018-10-16 22:32:42 +02:00
FdaSilvaYY
7f0e220f4d crypto/rand: fix some style nit's
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7378)

(cherry picked from commit c2e33a05b1)
2018-10-10 14:02:45 +02:00
Dr. Matthias St. Pierre
b262a00229 Replace the public RAND_DRBG_USED_FLAGS #define by an internal constant
The new DRBG API added the aforementioned #define. However, it is
used internally only and having it defined publicly does not serve
any purpose except causing potential version compatibility problems.

Fixes #7182

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7190)

(cherry picked from commit c402e943cd)
2018-09-12 23:48:18 +02:00
Kurt Roeckx
3cb7c5cfef Use void in all function definitions that do not take any arguments
Reviewed-by: Rich Salz <rsalz@openssl.org>
GH: #6208
2018-05-11 14:37:48 +02:00
Bernd Edlinger
bf7ae75000 Don't cleanup uninitialized thread local slots
Fixes: #6120

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/6123)
2018-04-28 19:09:55 +02:00
Bernd Edlinger
272c0df8e1 Fix drbg thread cleanup and error handling
Fixes: #6081

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6089)
2018-04-27 14:07:42 +02:00
Dr. Matthias St. Pierre
43687d685f DRBG: fix coverity issues
- drbg_lib.c: Silence coverity warning: the comment preceding the
  RAND_DRBG_instantiate() call explicitely states that the error
  is ignored and explains the reason why.

- drbgtest: Add checks for the return values of RAND_bytes() and
  RAND_priv_bytes() to run_multi_thread_test().

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5976)
2018-04-17 17:24:50 +02:00
Dr. Matthias St. Pierre
5bc6bcf82d DRBG: implement a get_nonce() callback
Fixes #5849

In pull request #5503 a fallback was added which adds a random nonce of
security_strength/2 bits if no nonce callback is provided. This change raised
the entropy requirements form 256 to 384 bit, which can cause problems on some
platforms (e.g. VMS, see issue #5849).

The requirements for the nonce are given in section 8.6.7 of NIST SP 800-90Ar1:

  A nonce may be required in the construction of a seed during instantiation
  in order to provide a security cushion to block certain attacks.
  The nonce shall be either:

  a) A value with at least (security_strength/2) bits of entropy, or

  b) A value that is expected to repeat no more often than a
     (security_strength/2)-bit random string would be expected to repeat.

  Each nonce shall be unique to the cryptographic module in which instantiation
  is performed, but need not be secret. When used, the nonce shall be considered
  to be a critical security parameter.

This commit implements a nonce of type b) in order to lower the entropy
requirements during instantiation back to 256 bits.

The formulation "shall be unique to the cryptographic module" above implies
that the nonce needs to be unique among (with high probability) among all
DRBG instances in "space" and "time". We try to achieve this goal by creating a
nonce of the following form

    nonce = app-specific-data || high-resolution-utc-timestamp || counter

Where || denotes concatenation. The application specific data can be something
like the process or group id of the application. A utc timestamp is used because
it increases monotonically, provided the system time is synchronized. This approach
may not be perfect yet for a FIPS evaluation, but it should be good enough for the
moment.

This commit also harmonizes the implementation of the get_nonce() and the
get_additional_data() callbacks and moves the platform specific parts from
rand_lib.c into rand_unix.c, rand_win.c, and rand_vms.c.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5920)
2018-04-13 20:49:28 +02:00
Kurt Roeckx
2a70d65b99 Make sure we use a nonce when a nonce is required
If a nonce is required and the get_nonce callback is NULL, request 50%
more entropy following NIST SP800-90Ar1 section 9.1.

Reviewed-by: Dr. Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
GH: #5503
2018-04-01 21:11:26 +02:00
Dr. Matthias St. Pierre
a73d990e2b Add documentation for the RAND_DRBG API
The RAND_DRBG API was added in PR #5462 and modified by PR #5547.
This commit adds the corresponding documention.

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5461)
2018-03-30 00:10:38 +02:00
Kurt Roeckx
7caf122e71 Make the public and private DRBG thread local
This avoids lock contention.

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/5547)
2018-03-19 15:04:40 +01:00
Kurt Roeckx
eb238134e0 Propagate the request for prediction resistance to the get entropy call
Reviewed-by: Dr. Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
GH: #5402
2018-03-17 11:35:33 +01:00
Bernd Edlinger
f96ff4e908 Fixed a crash in error handing of rand_drbg_new
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/5646)
2018-03-17 08:19:41 +01:00
Dr. Matthias St. Pierre
31393fd906 RAND_DRBG: add a function for setting the default DRBG type and flags
This commit adds a new api RAND_DRBG_set_defaults() which sets the
default type and flags for new DRBG instances. See also #5576.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5632)
2018-03-16 18:31:30 +01:00
Dr. Matthias St. Pierre
6decf9436f Publish the RAND_DRBG API
Fixes #4403

This commit moves the internal header file "internal/rand.h" to
<openssl/rand_drbg.h>, making the RAND_DRBG API public.
The RAND_POOL API remains private, its function prototypes were
moved to "internal/rand_int.h" and converted to lowercase.

Documentation for the new API is work in progress on GitHub #5461.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5462)
2018-03-15 18:58:38 +01:00
Dr. Matthias St. Pierre
4917e91160 RAND_DRBG: add a function for setting the reseeding defaults
The introduction of thread local public and private DRBG instances (#5547)
makes it very cumbersome to change the reseeding (time) intervals for
those instances. This commit provides a function to set the default
values for all subsequently created DRBG instances.

 int RAND_DRBG_set_reseed_defaults(
                                   unsigned int master_reseed_interval,
                                   unsigned int slave_reseed_interval,
                                   time_t master_reseed_time_interval,
                                   time_t slave_reseed_time_interval
                                   );

The function is intended only to be used during application initialization,
before any threads are created and before any random bytes are generated.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5576)
2018-03-10 00:26:30 +01:00
Kurt Roeckx
35503b7cdc Check the parent DRBG's strength
We currently don't support the algorithm from NIST SP 800-90C
10.1.2 to use a weaker DRBG as source

Reviewed-by: Dr. Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
GH: #5506
2018-03-06 18:34:23 +01:00
Dr. Matthias St. Pierre
812b153706 DRBG: make locking api truly private
In PR #5295 it was decided that the locking api should remain private
and used only inside libcrypto. However, the locking functions were added
back to `libcrypto.num` by `mkdef.pl`, because the function prototypes
were still listed in `internal/rand.h`. (This header contains functions
which are internal, but shared between libcrypto and libssl.)

This commit moves the prototypes to `rand_lcl.h` and changes the names
to lowercase, following the convention therein. It also corrects an
outdated documenting comment.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5375)
2018-02-15 12:25:01 +01:00
Dr. Matthias St. Pierre
8164d91d18 DRBG: make the derivation function the default for ctr_drbg
The NIST standard presents two alternative ways for seeding the
CTR DRBG, depending on whether a derivation function is used or not.
In Section 10.2.1 of NIST SP800-90Ar1 the following is assessed:

  The use of the derivation function is optional if either an
  approved RBG or an entropy source provides full entropy output
  when entropy input is requested by the DRBG mechanism.
  Otherwise, the derivation function shall be used.

Since the OpenSSL DRBG supports being reseeded from low entropy random
sources (using RAND_POOL), the use of a derivation function is mandatory.
For that reason we change the default and replace the opt-in flag
RAND_DRBG_FLAG_CTR_USE_DF with an opt-out flag RAND_DRBG_FLAG_CTR_NO_DF.
This change simplifies the RAND_DRBG_new() calls.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5294)
2018-02-13 17:32:54 +01:00
Dr. Matthias St. Pierre
4f9dabbfe3 DRBG: unify initialization and cleanup code
The functions drbg_setup() and drbg_cleanup() used to duplicate a lot of
code from RAND_DRBG_new() and RAND_DRBG_free(). This duplication has been
removed, which simplifies drbg_setup() and makes drbg_cleanup() obsolete.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5294)
2018-02-13 17:32:54 +01:00
Dr. Matthias St. Pierre
3ce1c27b56 DRBG: add locking api
This commit adds three new accessors to the internal DRBG lock

   int RAND_DRBG_lock(RAND_DRBG *drbg)
   int RAND_DRBG_unlock(RAND_DRBG *drbg)
   int RAND_DRBG_enable_locking(RAND_DRBG *drbg)

The three shared DRBGs are intended to be used concurrently, so they
have locking enabled by default. It is the callers responsibility to
guard access to the shared DRBGs by calls to RAND_DRBG_lock() and
RAND_DRBG_unlock().

All other DRBG instances don't have locking enabled by default, because
they are intendended to be used by a single thread. If it is desired,
locking can be enabled by using RAND_DRBG_enable_locking().

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5294)
2018-02-13 17:32:54 +01:00
Dr. Matthias St. Pierre
f61f62ea13 Use RAND_DRBG_bytes() for RAND_bytes() and RAND_priv_bytes()
The functions RAND_bytes() and RAND_priv_bytes() are now both based
on a common implementation using RAND_DRBG_bytes() (if the default
OpenSSL rand method is active). This not only simplifies the code
but also has the advantage that additional input from a high precision
timer is added on every generate call if the timer is available.

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/5251)
2018-02-05 20:05:14 +01:00
Dr. Matthias St. Pierre
1648338ba1 Fix size limitation of RAND_DRBG_bytes()
When comparing the implementations of drbg_bytes() and RAND_DRBG_bytes(),
it was noticed that the former split the buffer into chunks when calling
RAND_DRBG_generate() to circumvent the size limitation of the buffer
to outlen <= drb->max_request. This loop was missing in RAND_DRBG_bytes(),
so it was adopted from drbg_bytes().

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/5251)
2018-02-05 20:05:14 +01:00
Dr. Matthias St. Pierre
58351fbd02 drbg_bytes: remove check for DRBG_UNINITIALIZED state
This check not only prevented the automatic reinstantiation of the
DRBG, which is implemented in RAND_DRBG_generate(), but also prevented
an error message from being generated in the case of failure.

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/5251)
2018-02-05 20:05:14 +01:00
Benjamin Kaduk
63ab5ea13b Revert the crypto "global lock" implementation
Conceptually, this is a squashed version of:

    Revert "Address feedback"

    This reverts commit 75551e07bd.

and

    Revert "Add CRYPTO_thread_glock_new"

    This reverts commit ed6b2c7938.

But there were some intervening commits that made neither revert apply
cleanly, so instead do it all as one shot.

The crypto global locks were an attempt to cope with the awkward
POSIX semantics for pthread_atfork(); its documentation (the "RATIONALE"
section) indicates that the expected usage is to have the prefork handler
lock all "global" locks, and the parent and child handlers release those
locks, to ensure that forking happens with a consistent (lock) state.
However, the set of functions available in the child process is limited
to async-signal-safe functions, and pthread_mutex_unlock() is not on
the list of async-signal-safe functions!  The only synchronization
primitives that are async-signal-safe are the semaphore primitives,
which are not really appropriate for general-purpose usage.

However, the state consistency problem that the global locks were
attempting to solve is not actually a serious problem, particularly for
OpenSSL.  That is, we can consider four cases of forking application
that might use OpenSSL:

(1) Single-threaded, does not call into OpenSSL in the child (e.g.,
the child calls exec() immediately)

For this class of process, no locking is needed at all, since there is
only ever a single thread of execution and the only reentrancy is due to
signal handlers (which are themselves limited to async-signal-safe
operation and should not be doing much work at all).

(2) Single-threaded, calls into OpenSSL after fork()

The application must ensure that it does not fork() with an unexpected
lock held (that is, one that would get unlocked in the parent but
accidentally remain locked in the child and cause deadlock).  Since
OpenSSL does not expose any of its internal locks to the application
and the application is single-threaded, the OpenSSL internal locks
will be unlocked for the fork(), and the state will be consistent.
(OpenSSL will need to reseed its PRNG in the child, but that is
an orthogonal issue.)  If the application makes use of locks from
libcrypto, proper handling for those locks is the responsibility of
the application, as for any other locking primitive that is available
for application programming.

(3) Multi-threaded, does not call into OpenSSL after fork()

As for (1), the OpenSSL state is only relevant in the parent, so
no particular fork()-related handling is needed.  The internal locks
are relevant, but there is no interaction with the child to consider.

(4) Multi-threaded, calls into OpenSSL after fork()

This is the case where the pthread_atfork() hooks to ensure that all
global locks are in a known state across fork() would come into play,
per the above discussion.  However, these "calls into OpenSSL after
fork()" are still subject to the restriction to async-signal-safe
functions.  Since OpenSSL uses all sorts of locking and libc functions
that are not on the list of safe functions (e.g., malloc()), this
case is not currently usable and is unlikely to ever be usable,
independently of the locking situation.  So, there is no need to
go through contortions to attempt to support this case in the one small
area of locking interaction with fork().

In light of the above analysis (thanks @davidben and @achernya), go
back to the simpler implementation that does not need to distinguish
"library-global" locks or to have complicated atfork handling for locks.

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/5089)
2018-01-31 12:25:28 -06:00
Kurt Roeckx
20928ff635 Add RAND_DRBG_bytes
Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/4752)
2018-01-29 12:42:06 +01:00
Dr. Matthias St. Pierre
39571fcabf Fix memory leak in do_rand_drbg_init()
Fixes #5076

Since do_rand_drbg_init() allocates three locks, it needs to ensure
that OPENSSL_init_crypto() is called, otherwise these resources are
not cleaned up properly.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/5083)
2018-01-16 08:38:13 -06:00
Richard Levitte
3c7d0945b6 Update copyright years on all files merged since Jan 1st 2018
Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5038)
2018-01-09 05:49:01 +01:00
Dr. Matthias St. Pierre
8212d50576 crypto/rand: restore the generic DRBG implementation
The DRGB concept described in NIST SP 800-90A provides for having different
algorithms to generate random output. In fact, the FIPS object module used to
implement three of them, CTR DRBG, HASH DRBG and HMAC DRBG.

When the FIPS code was ported to master in #4019, two of the three algorithms
were dropped, and together with those the entire code that made RAND_DRBG
generic was removed, since only one concrete implementation was left.

This commit restores the original generic implementation of the DRBG, making it
possible again to add additional implementations using different algorithms
(like RAND_DRBG_CHACHA20) in the future.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4998)
2018-01-04 11:47:31 +10:00
Dr. Matthias St. Pierre
efb8128ad5 Make DRBG uninstantiate() and instantiate() methods inverse to each other
Previously, the RAND_DRBG_uninstantiate() call was not exactly inverse to
RAND_DRBG_instantiate(), because some important member values of the
drbg->ctr member where cleared. Now these values are restored internally.

Signed-off-by: Dr. Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/4402)
2017-12-17 23:12:10 +01:00