1. 08 11月, 2019 1 次提交
  2. 06 11月, 2018 1 次提交
  3. 17 10月, 2018 1 次提交
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      DRBG: fix reseeding via RAND_add()/RAND_seed() with large input · dbf0a496
      Dr. Matthias St. Pierre 提交于
      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: NPaul Dale <paul.dale@oracle.com>
      (Merged from https://github.com/openssl/openssl/pull/7382)
      
      (cherry picked from commit 3064b55134434a0b2850f07eff57120f35bb269a)
      dbf0a496
  4. 27 6月, 2018 1 次提交
  5. 02 5月, 2018 1 次提交
  6. 14 4月, 2018 1 次提交
    • D
      DRBG: implement a get_nonce() callback · 5bc6bcf8
      Dr. Matthias St. Pierre 提交于
      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: NRichard Levitte <levitte@openssl.org>
      (Merged from https://github.com/openssl/openssl/pull/5920)
      5bc6bcf8
  7. 05 4月, 2018 1 次提交
  8. 20 3月, 2018 1 次提交
  9. 19 3月, 2018 1 次提交
  10. 17 3月, 2018 1 次提交
  11. 16 3月, 2018 1 次提交
  12. 18 10月, 2017 1 次提交
    • D
      Fix reseeding issues of the public RAND_DRBG · c16de9d8
      Dr. Matthias St. Pierre 提交于
      Reseeding is handled very differently by the classic RAND_METHOD API
      and the new RAND_DRBG api. These differences led to some problems when
      the new RAND_DRBG was made the default OpenSSL RNG. In particular,
      RAND_add() did not work as expected anymore. These issues are discussed
      on the thread '[openssl-dev] Plea for a new public OpenSSL RNG API'
      and in Pull Request #4328. This commit fixes the mentioned issues,
      introducing the following changes:
      
      - Replace the fixed size RAND_BYTES_BUFFER by a new RAND_POOL API which
        facilitates collecting entropy by the get_entropy() callback.
      - Don't use RAND_poll()/RAND_add() for collecting entropy from the
        get_entropy() callback anymore. Instead, replace RAND_poll() by
        RAND_POOL_acquire_entropy().
      - Add a new function rand_drbg_restart() which tries to get the DRBG
        in an instantiated state by all means, regardless of the current
        state (uninstantiated, error, ...) the DRBG is in. If the caller
        provides entropy or additional input, it will be used for reseeding.
      - Restore the original documented behaviour of RAND_add() and RAND_poll()
        (namely to reseed the DRBG immediately) by a new implementation based
        on rand_drbg_restart().
      - Add automatic error recovery from temporary failures of the entropy
        source to RAND_DRBG_generate() using the rand_drbg_restart() function.
      Reviewed-by: NPaul Dale <paul.dale@oracle.com>
      Reviewed-by: NKurt Roeckx <kurt@roeckx.be>
      Reviewed-by: NRich Salz <rsalz@openssl.org>
      Reviewed-by: NBen Kaduk <kaduk@mit.edu>
      (Merged from https://github.com/openssl/openssl/pull/4328)
      c16de9d8
  13. 29 8月, 2017 1 次提交
  14. 07 8月, 2017 1 次提交
  15. 20 7月, 2017 1 次提交
  16. 18 5月, 2016 1 次提交
  17. 13 4月, 2016 4 次提交
  18. 18 3月, 2016 1 次提交