CHANGES

  *) Make it possible to have multiple active certificates with the same
     subject in the CA index file.  This is done only if the keyword
     'unique_subject' is set to 'no' in the main CA section (default
     if 'CA_default') of the configuration file.  The value is saved
     with the database itself in a separate index attribute file,
     named like the index file with '.attr' appended to the name.
     [Richard Levitte]

  *) Generate muti valued AVAs using '+' notation in config files for
     req and dirName.
     [Steve Henson]

  *) Support for nameConstraints certificate extension.
     [Steve Henson]

  *) Support for policyConstraints certificate extension.
     [Steve Henson]

  *) Support for policyMappings certificate extension.
     [Steve Henson]

  *) Make sure the default DSA_METHOD implementation only uses its
     dsa_mod_exp() and/or bn_mod_exp() handlers if they are non-NULL,
     and change its own handlers to be NULL so as to remove unnecessary
     indirection. This lets alternative implementations fallback to the
     default implementation more easily.
     [Geoff Thorpe]

  *) Support for directoryName in GeneralName related extensions
     in config files.
     [Steve Henson]

  *) Make it possible to link applications using Makefile.shared.
     Make that possible even when linking against static libraries!
     [Richard Levitte]

  *) Support for single pass processing for S/MIME signing. This now
     means that S/MIME signing can be done from a pipe, in addition
     cleartext signing (multipart/signed type) is effectively streaming
     and the signed data does not need to be all held in memory.

     This is done with a new flag PKCS7_STREAM. When this flag is set
     PKCS7_sign() only initializes the PKCS7 structure and the actual signing
     is done after the data is output (and digests calculated) in
     SMIME_write_PKCS7().
     [Steve Henson]

  *) Add full support for -rpath/-R, both in shared libraries and
     applications, at least on the platforms where it's known how
     to do it.
     [Richard Levitte]

  *) In crypto/ec/ec_mult.c, implement fast point multiplication with
     precomputation, based on wNAF splitting: EC_GROUP_precompute_mult()
     will now compute a table of multiples of the generator that
     makes subsequent invocations of EC_POINTs_mul() or EC_POINT_mul()
     faster (notably in the case of a single point multiplication,
     scalar * generator).
     [Nils Larsch, Bodo Moeller]

  *) IPv6 support for certificate extensions. The various extensions
     which use the IP:a.b.c.d can now take IPv6 addresses using the
     formats of RFC1884 2.2 . IPv6 addresses are now also displayed
     correctly.
     [Steve Henson]

  *) Added an ENGINE that implements RSA by performing private key
     exponentiations with the GMP library. The conversions to and from
     GMP's mpz_t format aren't optimised nor are any montgomery forms
     cached, and on x86 it appears OpenSSL's own performance has caught up.
     However there are likely to be other architectures where GMP could
     provide a boost. This ENGINE is not built in by default, but it can be
     specified at Configure time and should be accompanied by the necessary
     linker additions, eg;
         ./config -DOPENSSL_USE_GMP -lgmp
     [Geoff Thorpe]

  *) "openssl engine" will not display ENGINE/DSO load failure errors when
     testing availability of engines with "-t" - the old behaviour is
     produced by increasing the feature's verbosity with "-tt".
     [Geoff Thorpe]

  *) ECDSA routines: under certain error conditions uninitialized BN objects
     could be freed. Solution: make sure initialization is performed early
     enough. (Reported and fix supplied by Nils Larsch <nla@trustcenter.de>
     via PR#459)
     [Lutz Jaenicke]

  *) Key-generation can now be implemented in RSA_METHOD, DSA_METHOD
     and DH_METHOD (eg. by ENGINE implementations) to override the normal
     software implementations. For DSA and DH, parameter generation can
     also be overriden by providing the appropriate method callbacks.
     [Geoff Thorpe]

  *) Change the "progress" mechanism used in key-generation and
     primality testing to functions that take a new BN_GENCB pointer in
     place of callback/argument pairs. The new API functions have "_ex"
     postfixes and the older functions are reimplemented as wrappers for
     the new ones. The OPENSSL_NO_DEPRECATED symbol can be used to hide
     declarations of the old functions to help (graceful) attempts to
     migrate to the new functions. Also, the new key-generation API
     functions operate on a caller-supplied key-structure and return
     success/failure rather than returning a key or NULL - this is to
     help make "keygen" another member function of RSA_METHOD etc.

     Example for using the new callback interface:

          int (*my_callback)(int a, int b, BN_GENCB *cb) = ...;
          void *my_arg = ...;
          BN_GENCB my_cb;

          BN_GENCB_set(&my_cb, my_callback, my_arg);

          return BN_is_prime_ex(some_bignum, BN_prime_checks, NULL, &cb);
          /* For the meaning of a, b in calls to my_callback(), see the
           * documentation of the function that calls the callback.
           * cb will point to my_cb; my_arg can be retrieved as cb->arg.
           * my_callback should return 1 if it wants BN_is_prime_ex()
           * to continue, or 0 to stop.
           */

     [Geoff Thorpe]

  *) Change the ZLIB compression method to be stateful, and make it
     available to TLS with the number defined in 
     draft-ietf-tls-compression-04.txt.
     [Richard Levitte]

  *) Add the ASN.1 structures and functions for CertificatePair, which
     is defined as follows (according to X.509_4thEditionDraftV6.pdf):

     CertificatePair ::= SEQUENCE {
        forward		[0]	Certificate OPTIONAL,
        reverse		[1]	Certificate OPTIONAL,
        -- at least one of the pair shall be present -- }

     Also implement the PEM functions to read and write certificate
     pairs, and defined the PEM tag as "CERTIFICATE PAIR".

     This needed to be defined, mostly for the sake of the LDAP
     attribute crossCertificatePair, but may prove useful elsewhere as
     well.
     [Richard Levitte]

  *) Make it possible to inhibit symlinking of shared libraries in
     Makefile.shared, for Cygwin's sake.
     [Richard Levitte]

  *) Extend the BIGNUM API by creating a function 
          void BN_set_negative(BIGNUM *a, int neg);
     and a macro that behave like
          int  BN_is_negative(const BIGNUM *a);

     to avoid the need to access 'a->neg' directly in applications.
     [Nils Larsch]

  *) Implement fast modular reduction for pseudo-Mersenne primes
     used in NIST curves (crypto/bn/bn_nist.c, crypto/ec/ecp_nist.c).
     EC_GROUP_new_curve_GFp() will now automatically use this
     if applicable.
     [Nils Larsch <nla@trustcenter.de>]

  *) Add new lock type (CRYPTO_LOCK_BN).
     [Bodo Moeller]

  *) Change the ENGINE framework to automatically load engines
     dynamically from specific directories unless they could be
     found to already be built in or loaded.  Move all the
     current engines except for the cryptodev one to a new
     directory engines/.
     The engines in engines/ are built as shared libraries if
     the "shared" options was given to ./Configure or ./config.
     Otherwise, they are inserted in libcrypto.a.
     /usr/local/ssl/engines is the default directory for dynamic
     engines, but that can be overriden at configure time through
     the usual use of --prefix and/or --openssldir, and at run
     time with the environment variable OPENSSL_ENGINES.
     [Geoff Thorpe and Richard Levitte]

  *) Add Makefile.shared, a helper makefile to build shared
     libraries.  Addapt Makefile.org.
     [Richard Levitte]

  *) Add version info to Win32 DLLs.
     [Peter 'Luna' Runestig" <peter@runestig.com>]

  *) Add new 'medium level' PKCS#12 API. Certificates and keys
     can be added using this API to created arbitrary PKCS#12
     files while avoiding the low level API.

     New options to PKCS12_create(), key or cert can be NULL and
     will then be omitted from the output file. The encryption
     algorithm NIDs can be set to -1 for no encryption, the mac
     iteration count can be set to 0 to omit the mac.

     Enhance pkcs12 utility by making the -nokeys and -nocerts
     options work when creating a PKCS#12 file. New option -nomac
     to omit the mac, NONE can be set for an encryption algorithm.
     New code is modified to use the enhanced PKCS12_create()
     instead of the low level API.
     [Steve Henson]

  *) Extend ASN1 encoder to support indefinite length constructed
     encoding. This can output sequences tags and octet strings in
     this form. Modify pk7_asn1.c to support indefinite length
     encoding. This is experimental and needs additional code to
     be useful, such as an ASN1 bio and some enhanced streaming
     PKCS#7 code.

     Extend template encode functionality so that tagging is passed
     down to the template encoder.
     [Steve Henson]

  *) Let 'openssl req' fail if an argument to '-newkey' is not
     recognized instead of using RSA as a default.
     [Bodo Moeller]

  *) Add support for ECC-based ciphersuites from draft-ietf-tls-ecc-01.txt.
     As these are not official, they are not included in "ALL";
     the "ECCdraft" ciphersuite group alias can be used to select them.
     [Vipul Gupta and Sumit Gupta (Sun Microsystems Laboratories)]

  *) Add ECDH engine support.
     [Nils Gura and Douglas Stebila (Sun Microsystems Laboratories)]

  *) Add ECDH in new directory crypto/ecdh/.
     [Douglas Stebila (Sun Microsystems Laboratories)]

  *) Let BN_rand_range() abort with an error after 100 iterations
     without success (which indicates a broken PRNG).
     [Bodo Moeller]

  *) Change BN_mod_sqrt() so that it verifies that the input value
     is really the square of the return value.  (Previously,
     BN_mod_sqrt would show GIGO behaviour.)
     [Bodo Moeller]

  *) Add named elliptic curves over binary fields from X9.62, SECG,
     and WAP/WTLS; add OIDs that were still missing.

     [Sheueling Chang Shantz and Douglas Stebila
     (Sun Microsystems Laboratories)]

  *) Extend the EC library for elliptic curves over binary fields
     (new files ec2_smpl.c, ec2_smpt.c, ec2_mult.c in crypto/ec/).
     New EC_METHOD:

          EC_GF2m_simple_method

     New API functions:

          EC_GROUP_new_curve_GF2m
          EC_GROUP_set_curve_GF2m
          EC_GROUP_get_curve_GF2m
          EC_POINT_set_affine_coordinates_GF2m
          EC_POINT_get_affine_coordinates_GF2m
          EC_POINT_set_compressed_coordinates_GF2m

     Point compression for binary fields is disabled by default for
     patent reasons (compile with OPENSSL_EC_BIN_PT_COMP defined to
     enable it).

     As binary polynomials are represented as BIGNUMs, various members
     of the EC_GROUP and EC_POINT data structures can be shared
     between the implementations for prime fields and binary fields;
     the above ..._GF2m functions (except for EX_GROUP_new_curve_GF2m)
     are essentially identical to their ..._GFp counterparts.
     (For simplicity, the '..._GFp' prefix has been dropped from
     various internal method names.)

     An internal 'field_div' method (similar to 'field_mul' and
     'field_sqr') has been added; this is used only for binary fields.

     [Sheueling Chang Shantz and Douglas Stebila
     (Sun Microsystems Laboratories)]

  *) Optionally dispatch EC_POINT_mul(), EC_POINT_precompute_mult()
     through methods ('mul', 'precompute_mult').

     The generic implementations (now internally called 'ec_wNAF_mul'
     and 'ec_wNAF_precomputed_mult') remain the default if these
     methods are undefined.

     [Sheueling Chang Shantz and Douglas Stebila
     (Sun Microsystems Laboratories)]

  *) New function EC_GROUP_get_degree, which is defined through
     EC_METHOD.  For curves over prime fields, this returns the bit
     length of the modulus.

     [Sheueling Chang Shantz and Douglas Stebila
     (Sun Microsystems Laboratories)]

  *) New functions EC_GROUP_dup, EC_POINT_dup.
     (These simply call ..._new  and ..._copy).

     [Sheueling Chang Shantz and Douglas Stebila
     (Sun Microsystems Laboratories)]

  *) Add binary polynomial arithmetic software in crypto/bn/bn_gf2m.c.
     Polynomials are represented as BIGNUMs (where the sign bit is not
     used) in the following functions [macros]:  

          BN_GF2m_add
          BN_GF2m_sub             [= BN_GF2m_add]
          BN_GF2m_mod             [wrapper for BN_GF2m_mod_arr]
          BN_GF2m_mod_mul         [wrapper for BN_GF2m_mod_mul_arr]
          BN_GF2m_mod_sqr         [wrapper for BN_GF2m_mod_sqr_arr]
          BN_GF2m_mod_inv
          BN_GF2m_mod_exp         [wrapper for BN_GF2m_mod_exp_arr]
          BN_GF2m_mod_sqrt        [wrapper for BN_GF2m_mod_sqrt_arr]
          BN_GF2m_mod_solve_quad  [wrapper for BN_GF2m_mod_solve_quad_arr]
          BN_GF2m_cmp             [= BN_ucmp]

     (Note that only the 'mod' functions are actually for fields GF(2^m).
     BN_GF2m_add() is misnomer, but this is for the sake of consistency.)

     For some functions, an the irreducible polynomial defining a
     field can be given as an 'unsigned int[]' with strictly
     decreasing elements giving the indices of those bits that are set;
     i.e., p[] represents the polynomial
          f(t) = t^p[0] + t^p[1] + ... + t^p[k]
     where
          p[0] > p[1] > ... > p[k] = 0.
     This applies to the following functions:

          BN_GF2m_mod_arr
          BN_GF2m_mod_mul_arr
          BN_GF2m_mod_sqr_arr
          BN_GF2m_mod_inv_arr        [wrapper for BN_GF2m_mod_inv]
          BN_GF2m_mod_div_arr        [wrapper for BN_GF2m_mod_div]
          BN_GF2m_mod_exp_arr
          BN_GF2m_mod_sqrt_arr
          BN_GF2m_mod_solve_quad_arr
          BN_GF2m_poly2arr
          BN_GF2m_arr2poly

     Conversion can be performed by the following functions:

          BN_GF2m_poly2arr
          BN_GF2m_arr2poly

     bntest.c has additional tests for binary polynomial arithmetic.

     Two implementations for BN_GF2m_mod_div() are available.
     The default algorithm simply uses BN_GF2m_mod_inv() and
     BN_GF2m_mod_mul().  The alternative algorithm is compiled in only
     if OPENSSL_SUN_GF2M_DIV is defined (patent pending; read the
     copyright notice in crypto/bn/bn_gf2m.c before enabling it).

     [Sheueling Chang Shantz and Douglas Stebila
     (Sun Microsystems Laboratories)]

  *) Add new error code 'ERR_R_DISABLED' that can be used when some
     functionality is disabled at compile-time.
     [Douglas Stebila <douglas.stebila@sun.com>]

  *) Change default behaviour of 'openssl asn1parse' so that more
     information is visible when viewing, e.g., a certificate:

     Modify asn1_parse2 (crypto/asn1/asn1_par.c) so that in non-'dump'
     mode the content of non-printable OCTET STRINGs is output in a
     style similar to INTEGERs, but with '[HEX DUMP]' prepended to
     avoid the appearance of a printable string.
     [Nils Larsch <nla@trustcenter.de>]

  *) Add 'asn1_flag' and 'asn1_form' member to EC_GROUP with access
     functions
          EC_GROUP_set_asn1_flag()
          EC_GROUP_get_asn1_flag()
          EC_GROUP_set_point_conversion_form()
          EC_GROUP_get_point_conversion_form()
     These control ASN1 encoding details:
     - Curves (i.e., groups) are encoded explicitly unless asn1_flag
       has been set to OPENSSL_EC_NAMED_CURVE.
     - Points are encoded in uncompressed form by default; options for
       asn1_for are as for point2oct, namely
          POINT_CONVERSION_COMPRESSED
          POINT_CONVERSION_UNCOMPRESSED
          POINT_CONVERSION_HYBRID

     Also add 'seed' and 'seed_len' members to EC_GROUP with access
     functions
          EC_GROUP_set_seed()
          EC_GROUP_get0_seed()
          EC_GROUP_get_seed_len()
     This is used only for ASN1 purposes (so far).
     [Nils Larsch <nla@trustcenter.de>]

  *) Add 'field_type' member to EC_METHOD, which holds the NID
     of the appropriate field type OID.  The new function
     EC_METHOD_get_field_type() returns this value.
     [Nils Larsch <nla@trustcenter.de>]

  *) Add functions 
          EC_POINT_point2bn()
          EC_POINT_bn2point()
          EC_POINT_point2hex()
          EC_POINT_hex2point()
     providing useful interfaces to EC_POINT_point2oct() and
     EC_POINT_oct2point().
     [Nils Larsch <nla@trustcenter.de>]

  *) Change internals of the EC library so that the functions
          EC_GROUP_set_generator()
          EC_GROUP_get_generator()
          EC_GROUP_get_order()
          EC_GROUP_get_cofactor()
     are implemented directly in crypto/ec/ec_lib.c and not dispatched
     to methods, which would lead to unnecessary code duplication when
     adding different types of curves.
     [Nils Larsch <nla@trustcenter.de> with input by Bodo Moeller]

  *) Implement compute_wNAF (crypto/ec/ec_mult.c) without BIGNUM
     arithmetic, and such that modified wNAFs are generated
     (which avoid length expansion in many cases).
     [Bodo Moeller]

  *) Add a function EC_GROUP_check_discriminant() (defined via
     EC_METHOD) that verifies that the curve discriminant is non-zero.

     Add a function EC_GROUP_check() that makes some sanity tests
     on a EC_GROUP, its generator and order.  This includes
     EC_GROUP_check_discriminant().
     [Nils Larsch <nla@trustcenter.de>]

  *) Add ECDSA in new directory crypto/ecdsa/.

     Add applications 'openssl ecparam' and 'openssl ecdsa'
     (these are based on 'openssl dsaparam' and 'openssl dsa').

     ECDSA support is also included in various other files across the
     library.  Most notably,
     - 'openssl req' now has a '-newkey ecdsa:file' option;
     - EVP_PKCS82PKEY (crypto/evp/evp_pkey.c) now can handle ECDSA;
     - X509_PUBKEY_get (crypto/asn1/x_pubkey.c) and
       d2i_PublicKey (crypto/asn1/d2i_pu.c) have been modified to make
       them suitable for ECDSA where domain parameters must be
       extracted before the specific public key;
     - ECDSA engine support has been added.
     [Nils Larsch <nla@trustcenter.de>]

  *) Include some named elliptic curves, and add OIDs from X9.62,
     SECG, and WAP/WTLS.  Each curve can be obtained from the new
     function
          EC_GROUP_new_by_curve_name(),
     and the list of available named curves can be obtained with
          EC_get_builtin_curves().
     Also add a 'curve_name' member to EC_GROUP objects, which can be
     accessed via
         EC_GROUP_set_curve_name()
         EC_GROUP_get_curve_name()
     [Nils Larsch <larsch@trustcenter.de, Bodo Moeller]
 
  *) Remove a few calls to bn_wexpand() in BN_sqr() (the one in there
     was actually never needed) and in BN_mul().  The removal in BN_mul()
     required a small change in bn_mul_part_recursive() and the addition
     of the functions bn_cmp_part_words(), bn_sub_part_words() and
     bn_add_part_words(), which do the same thing as bn_cmp_words(),
     bn_sub_words() and bn_add_words() except they take arrays with
     differing sizes.
     [Richard Levitte]

 Changes between 0.9.7l and 0.9.7m  [23 Feb 2007]

  *) Cleanse PEM buffers before freeing them since they may contain 
     sensitive data.
     [Benjamin Bennett <ben@psc.edu>]

  *) Include "!eNULL" in SSL_DEFAULT_CIPHER_LIST to make sure that
     a ciphersuite string such as "DEFAULT:RSA" cannot enable
     authentication-only ciphersuites.
     [Bodo Moeller]

  *) Since AES128 and AES256 share a single mask bit in the logic of
     ssl/ssl_ciph.c, the code for masking out disabled ciphers needs a
     kludge to work properly if AES128 is available and AES256 isn't.
     [Victor Duchovni]

  *) Expand security boundary to match 1.1.1 module.
     [Steve Henson]

  *) Remove redundant features: hash file source, editing of test vectors
     modify fipsld to use external fips_premain.c signature.
     [Steve Henson]

  *) New perl script mkfipsscr.pl to create shell scripts or batch files to
     run algorithm test programs.
     [Steve Henson]

  *) Make algorithm test programs more tolerant of whitespace.
     [Steve Henson]

  *) Have SSL/TLS server implementation tolerate "mismatched" record
     protocol version while receiving ClientHello even if the
     ClientHello is fragmented.  (The server can't insist on the
     particular protocol version it has chosen before the ServerHello
     message has informed the client about his choice.)
     [Bodo Moeller]

  *) Load error codes if they are not already present instead of using a
     static variable. This allows them to be cleanly unloaded and reloaded.
     [Steve Henson]

 Changes between 0.9.7k and 0.9.7l  [28 Sep 2006]

  *) Introduce limits to prevent malicious keys being able to
     cause a denial of service.  (CVE-2006-2940)
     [Steve Henson, Bodo Moeller]

  *) Fix ASN.1 parsing of certain invalid structures that can result
     in a denial of service.  (CVE-2006-2937)  [Steve Henson]

  *) Fix buffer overflow in SSL_get_shared_ciphers() function. 
     (CVE-2006-3738) [Tavis Ormandy and Will Drewry, Google Security Team]

  *) Fix SSL client code which could crash if connecting to a
     malicious SSLv2 server.  (CVE-2006-4343)
     [Tavis Ormandy and Will Drewry, Google Security Team]

  *) Change ciphersuite string processing so that an explicit
     ciphersuite selects this one ciphersuite (so that "AES256-SHA"
     will no longer include "AES128-SHA"), and any other similar
     ciphersuite (same bitmap) from *other* protocol versions (so that
     "RC4-MD5" will still include both the SSL 2.0 ciphersuite and the
     SSL 3.0/TLS 1.0 ciphersuite).  This is a backport combining
     changes from 0.9.8b and 0.9.8d.
     [Bodo Moeller]

 Changes between 0.9.7j and 0.9.7k  [05 Sep 2006]

  *) Avoid PKCS #1 v1.5 signature attack discovered by Daniel Bleichenbacher
     (CVE-2006-4339)  [Ben Laurie and Google Security Team]

  *) Change the Unix randomness entropy gathering to use poll() when
     possible instead of select(), since the latter has some
     undesirable limitations.
     [Darryl Miles via Richard Levitte and Bodo Moeller]

  *) Disable rogue ciphersuites:

      - SSLv2 0x08 0x00 0x80 ("RC4-64-MD5")
      - SSLv3/TLSv1 0x00 0x61 ("EXP1024-RC2-CBC-MD5")
      - SSLv3/TLSv1 0x00 0x60 ("EXP1024-RC4-MD5")

     The latter two were purportedly from
     draft-ietf-tls-56-bit-ciphersuites-0[01].txt, but do not really
     appear there.

     Also deactive the remaining ciphersuites from
     draft-ietf-tls-56-bit-ciphersuites-01.txt.  These are just as
     unofficial, and the ID has long expired.
     [Bodo Moeller]

  *) Fix RSA blinding Heisenbug (problems sometimes occured on
     dual-core machines) and other potential thread-safety issues.
     [Bodo Moeller]

 Changes between 0.9.7i and 0.9.7j  [04 May 2006]

  *) Adapt fipsld and the build system to link against the validated FIPS
     module in FIPS mode.
     [Steve Henson]

  *) Fixes for VC++ 2005 build under Windows.
     [Steve Henson]

  *) Add new Windows build target VC-32-GMAKE for VC++. This uses GNU make 
     from a Windows bash shell such as MSYS. It is autodetected from the
     "config" script when run from a VC++ environment. Modify standard VC++
     build to use fipscanister.o from the GNU make build. 
     [Steve Henson]

 Changes between 0.9.7h and 0.9.7i  [14 Oct 2005]

  *) Wrapped the definition of EVP_MAX_MD_SIZE in a #ifdef OPENSSL_FIPS.
     The value now differs depending on if you build for FIPS or not.
     BEWARE!  A program linked with a shared FIPSed libcrypto can't be
     safely run with a non-FIPSed libcrypto, as it may crash because of
     the difference induced by this change.
     [Andy Polyakov]

 Changes between 0.9.7g and 0.9.7h  [11 Oct 2005]

  *) Remove the functionality of SSL_OP_MSIE_SSLV2_RSA_PADDING
     (part of SSL_OP_ALL).  This option used to disable the
     countermeasure against man-in-the-middle protocol-version
     rollback in the SSL 2.0 server implementation, which is a bad
     idea.  (CVE-2005-2969)

     [Bodo Moeller; problem pointed out by Yutaka Oiwa (Research Center
     for Information Security, National Institute of Advanced Industrial
     Science and Technology [AIST], Japan)]

  *) Minimal support for X9.31 signatures and PSS padding modes. This is
     mainly for FIPS compliance and not fully integrated at this stage.
     [Steve Henson]

  *) For DSA signing, unless DSA_FLAG_NO_EXP_CONSTTIME is set, perform
     the exponentiation using a fixed-length exponent.  (Otherwise,
     the information leaked through timing could expose the secret key
     after many signatures; cf. Bleichenbacher's attack on DSA with
     biased k.)
     [Bodo Moeller]

  *) Make a new fixed-window mod_exp implementation the default for
     RSA, DSA, and DH private-key operations so that the sequence of
     squares and multiplies and the memory access pattern are
     independent of the particular secret key.  This will mitigate
     cache-timing and potential related attacks.

     BN_mod_exp_mont_consttime() is the new exponentiation implementation,
     and this is automatically used by BN_mod_exp_mont() if the new flag
     BN_FLG_EXP_CONSTTIME is set for the exponent.  RSA, DSA, and DH
     will use this BN flag for private exponents unless the flag
     RSA_FLAG_NO_EXP_CONSTTIME, DSA_FLAG_NO_EXP_CONSTTIME, or
     DH_FLAG_NO_EXP_CONSTTIME, respectively, is set.

     [Matthew D Wood (Intel Corp), with some changes by Bodo Moeller]

  *) Change the client implementation for SSLv23_method() and
     SSLv23_client_method() so that is uses the SSL 3.0/TLS 1.0
     Client Hello message format if the SSL_OP_NO_SSLv2 option is set.
     (Previously, the SSL 2.0 backwards compatible Client Hello
     message format would be used even with SSL_OP_NO_SSLv2.)
     [Bodo Moeller]

  *) Add support for smime-type MIME parameter in S/MIME messages which some
     clients need.
     [Steve Henson]

  *) New function BN_MONT_CTX_set_locked() to set montgomery parameters in
     a threadsafe manner. Modify rsa code to use new function and add calls
     to dsa and dh code (which had race conditions before).
     [Steve Henson]

  *) Include the fixed error library code in the C error file definitions
     instead of fixing them up at runtime. This keeps the error code
     structures constant.
     [Steve Henson]

 Changes between 0.9.7f and 0.9.7g  [11 Apr 2005]

  [NB: OpenSSL 0.9.7h and later 0.9.7 patch levels were released after
  OpenSSL 0.9.8.]

  *) Fixes for newer kerberos headers. NB: the casts are needed because
     the 'length' field is signed on one version and unsigned on another
     with no (?) obvious way to tell the difference, without these VC++
     complains. Also the "definition" of FAR (blank) is no longer included
     nor is the error ENOMEM. KRB5_PRIVATE has to be set to 1 to pick up
     some needed definitions.
     [Steve Henson]

  *) Undo Cygwin change.
     [Ulf Möller]

  *) Added support for proxy certificates according to RFC 3820.
     Because they may be a security thread to unaware applications,
     they must be explicitely allowed in run-time.  See
     docs/HOWTO/proxy_certificates.txt for further information.
     [Richard Levitte]

 Changes between 0.9.7e and 0.9.7f  [22 Mar 2005]

  *) Use (SSL_RANDOM_VALUE - 4) bytes of pseudo random data when generating
     server and client random values. Previously
     (SSL_RANDOM_VALUE - sizeof(time_t)) would be used which would result in
     less random data when sizeof(time_t) > 4 (some 64 bit platforms).

     This change has negligible security impact because:

     1. Server and client random values still have 24 bytes of pseudo random
        data.

     2. Server and client random values are sent in the clear in the initial
        handshake.

     3. The master secret is derived using the premaster secret (48 bytes in
        size for static RSA ciphersuites) as well as client server and random
        values.

     The OpenSSL team would like to thank the UK NISCC for bringing this issue
     to our attention. 

     [Stephen Henson, reported by UK NISCC]

  *) Use Windows randomness collection on Cygwin.
     [Ulf Möller]

  *) Fix hang in EGD/PRNGD query when communication socket is closed
     prematurely by EGD/PRNGD.
     [Darren Tucker <dtucker@zip.com.au> via Lutz Jänicke, resolves #1014]

  *) Prompt for pass phrases when appropriate for PKCS12 input format.
     [Steve Henson]

  *) Back-port of selected performance improvements from development
     branch, as well as improved support for PowerPC platforms.
     [Andy Polyakov]

  *) Add lots of checks for memory allocation failure, error codes to indicate
     failure and freeing up memory if a failure occurs.
     [Nauticus Networks SSL Team <openssl@nauticusnet.com>, Steve Henson]

  *) Add new -passin argument to dgst.
     [Steve Henson]

  *) Perform some character comparisons of different types in X509_NAME_cmp:
     this is needed for some certificates that reencode DNs into UTF8Strings
     (in violation of RFC3280) and can't or wont issue name rollover
     certificates.
     [Steve Henson]

  *) Make an explicit check during certificate validation to see that
     the CA setting in each certificate on the chain is correct.  As a
     side effect always do the following basic checks on extensions,
     not just when there's an associated purpose to the check:

      - if there is an unhandled critical extension (unless the user
        has chosen to ignore this fault)
      - if the path length has been exceeded (if one is set at all)
      - that certain extensions fit the associated purpose (if one has
        been given)
     [Richard Levitte]

 Changes between 0.9.7d and 0.9.7e  [25 Oct 2004]

  *) Avoid a race condition when CRLs are checked in a multi threaded 
     environment. This would happen due to the reordering of the revoked
     entries during signature checking and serial number lookup. Now the
     encoding is cached and the serial number sort performed under a lock.
     Add new STACK function sk_is_sorted().
     [Steve Henson]

  *) Add Delta CRL to the extension code.
     [Steve Henson]

  *) Various fixes to s3_pkt.c so alerts are sent properly.
     [David Holmes <d.holmes@f5.com>]

  *) Reduce the chances of duplicate issuer name and serial numbers (in
     violation of RFC3280) using the OpenSSL certificate creation utilities.
     This is done by creating a random 64 bit value for the initial serial
     number when a serial number file is created or when a self signed
     certificate is created using 'openssl req -x509'. The initial serial
     number file is created using 'openssl x509 -next_serial' in CA.pl
     rather than being initialized to 1.
     [Steve Henson]

 Changes between 0.9.7c and 0.9.7d  [17 Mar 2004]

  *) Fix null-pointer assignment in do_change_cipher_spec() revealed           
     by using the Codenomicon TLS Test Tool (CVE-2004-0079)                    
     [Joe Orton, Steve Henson]   

  *) Fix flaw in SSL/TLS handshaking when using Kerberos ciphersuites
     (CVE-2004-0112)
     [Joe Orton, Steve Henson]   

  *) Make it possible to have multiple active certificates with the same
     subject in the CA index file.  This is done only if the keyword
     'unique_subject' is set to 'no' in the main CA section (default
     if 'CA_default') of the configuration file.  The value is saved
     with the database itself in a separate index attribute file,
     named like the index file with '.attr' appended to the name.
     [Richard Levitte]

  *) X509 verify fixes. Disable broken certificate workarounds when 
     X509_V_FLAGS_X509_STRICT is set. Check CRL issuer has cRLSign set if
     keyUsage extension present. Don't accept CRLs with unhandled critical
     extensions: since verify currently doesn't process CRL extensions this
     rejects a CRL with *any* critical extensions. Add new verify error codes
     for these cases.
     [Steve Henson]

  *) When creating an OCSP nonce use an OCTET STRING inside the extnValue.
     A clarification of RFC2560 will require the use of OCTET STRINGs and 
     some implementations cannot handle the current raw format. Since OpenSSL
     copies and compares OCSP nonces as opaque blobs without any attempt at
     parsing them this should not create any compatibility issues.
     [Steve Henson]

  *) New md flag EVP_MD_CTX_FLAG_REUSE this allows md_data to be reused when
     calling EVP_MD_CTX_copy_ex() to avoid calling OPENSSL_malloc(). Without
     this HMAC (and other) operations are several times slower than OpenSSL
     < 0.9.7.
     [Steve Henson]

  *) Print out GeneralizedTime and UTCTime in ASN1_STRING_print_ex().
     [Peter Sylvester <Peter.Sylvester@EdelWeb.fr>]

  *) Use the correct content when signing type "other".
     [Steve Henson]

 Changes between 0.9.7b and 0.9.7c  [30 Sep 2003]

  *) Fix various bugs revealed by running the NISCC test suite:

     Stop out of bounds reads in the ASN1 code when presented with
     invalid tags (CVE-2003-0543 and CVE-2003-0544).
     
     Free up ASN1_TYPE correctly if ANY type is invalid (CVE-2003-0545).

     If verify callback ignores invalid public key errors don't try to check
     certificate signature with the NULL public key.

     [Steve Henson]

  *) New -ignore_err option in ocsp application to stop the server
     exiting on the first error in a request.
     [Steve Henson]

  *) In ssl3_accept() (ssl/s3_srvr.c) only accept a client certificate
     if the server requested one: as stated in TLS 1.0 and SSL 3.0
     specifications.
     [Steve Henson]

  *) In ssl3_get_client_hello() (ssl/s3_srvr.c), tolerate additional
     extra data after the compression methods not only for TLS 1.0
     but also for SSL 3.0 (as required by the specification).
     [Bodo Moeller; problem pointed out by Matthias Loepfe]

  *) Change X509_certificate_type() to mark the key as exported/exportable
     when it's 512 *bits* long, not 512 bytes.
     [Richard Levitte]

  *) Change AES_cbc_encrypt() so it outputs exact multiple of
     blocks during encryption.
     [Richard Levitte]

  *) Various fixes to base64 BIO and non blocking I/O. On write 
     flushes were not handled properly if the BIO retried. On read
     data was not being buffered properly and had various logic bugs.
     This also affects blocking I/O when the data being decoded is a
     certain size.
     [Steve Henson]

  *) Various S/MIME bugfixes and compatibility changes:
     output correct application/pkcs7 MIME type if
     PKCS7_NOOLDMIMETYPE is set. Tolerate some broken signatures.
     Output CR+LF for EOL if PKCS7_CRLFEOL is set (this makes opening
     of files as .eml work). Correctly handle very long lines in MIME
     parser.
     [Steve Henson]

 Changes between 0.9.7a and 0.9.7b  [10 Apr 2003]

  *) Countermeasure against the Klima-Pokorny-Rosa extension of
     Bleichbacher's attack on PKCS #1 v1.5 padding: treat
     a protocol version number mismatch like a decryption error
     in ssl3_get_client_key_exchange (ssl/s3_srvr.c).
     [Bodo Moeller]

  *) Turn on RSA blinding by default in the default implementation
     to avoid a timing attack. Applications that don't want it can call
     RSA_blinding_off() or use the new flag RSA_FLAG_NO_BLINDING.
     They would be ill-advised to do so in most cases.
     [Ben Laurie, Steve Henson, Geoff Thorpe, Bodo Moeller]

  *) Change RSA blinding code so that it works when the PRNG is not
     seeded (in this case, the secret RSA exponent is abused as
     an unpredictable seed -- if it is not unpredictable, there
     is no point in blinding anyway).  Make RSA blinding thread-safe
     by remembering the creator's thread ID in rsa->blinding and
     having all other threads use local one-time blinding factors
     (this requires more computation than sharing rsa->blinding, but
     avoids excessive locking; and if an RSA object is not shared
     between threads, blinding will still be very fast).
     [Bodo Moeller]

  *) Fixed a typo bug that would cause ENGINE_set_default() to set an
     ENGINE as defaults for all supported algorithms irrespective of
     the 'flags' parameter. 'flags' is now honoured, so applications
     should make sure they are passing it correctly.
     [Geoff Thorpe]

  *) Target "mingw" now allows native Windows code to be generated in
     the Cygwin environment as well as with the MinGW compiler.
     [Ulf Moeller] 

 Changes between 0.9.7 and 0.9.7a  [19 Feb 2003]

  *) In ssl3_get_record (ssl/s3_pkt.c), minimize information leaked
     via timing by performing a MAC computation even if incorrrect
     block cipher padding has been found.  This is a countermeasure
     against active attacks where the attacker has to distinguish
     between bad padding and a MAC verification error. (CVE-2003-0078)

     [Bodo Moeller; problem pointed out by Brice Canvel (EPFL),
     Alain Hiltgen (UBS), Serge Vaudenay (EPFL), and
     Martin Vuagnoux (EPFL, Ilion)]

  *) Make the no-err option work as intended.  The intention with no-err
     is not to have the whole error stack handling routines removed from
     libcrypto, it's only intended to remove all the function name and
     reason texts, thereby removing some of the footprint that may not
     be interesting if those errors aren't displayed anyway.

     NOTE: it's still possible for any application or module to have it's
     own set of error texts inserted.  The routines are there, just not
     used by default when no-err is given.
     [Richard Levitte]

  *) Add support for FreeBSD on IA64.
     [dirk.meyer@dinoex.sub.org via Richard Levitte, resolves #454]

  *) Adjust DES_cbc_cksum() so it returns the same value as the MIT
     Kerberos function mit_des_cbc_cksum().  Before this change,
     the value returned by DES_cbc_cksum() was like the one from
     mit_des_cbc_cksum(), except the bytes were swapped.
     [Kevin Greaney <Kevin.Greaney@hp.com> and Richard Levitte]

  *) Allow an application to disable the automatic SSL chain building.
     Before this a rather primitive chain build was always performed in
     ssl3_output_cert_chain(): an application had no way to send the 
     correct chain if the automatic operation produced an incorrect result.

     Now the chain builder is disabled if either:

     1. Extra certificates are added via SSL_CTX_add_extra_chain_cert().

     2. The mode flag SSL_MODE_NO_AUTO_CHAIN is set.

     The reasoning behind this is that an application would not want the
     auto chain building to take place if extra chain certificates are
     present and it might also want a means of sending no additional
     certificates (for example the chain has two certificates and the
     root is omitted).
     [Steve Henson]

  *) Add the possibility to build without the ENGINE framework.
     [Steven Reddie <smr@essemer.com.au> via Richard Levitte]

  *) Under Win32 gmtime() can return NULL: check return value in
     OPENSSL_gmtime(). Add error code for case where gmtime() fails.
     [Steve Henson]

  *) DSA routines: under certain error conditions uninitialized BN objects
     could be freed. Solution: make sure initialization is performed early
     enough. (Reported and fix supplied by Ivan D Nestlerode <nestler@MIT.EDU>,
     Nils Larsch <nla@trustcenter.de> via PR#459)
     [Lutz Jaenicke]

  *) Another fix for SSLv2 session ID handling: the session ID was incorrectly
     checked on reconnect on the client side, therefore session resumption
     could still fail with a "ssl session id is different" error. This
     behaviour is masked when SSL_OP_ALL is used due to
     SSL_OP_MICROSOFT_SESS_ID_BUG being set.
     Behaviour observed by Crispin Flowerday <crispin@flowerday.cx> as
     followup to PR #377.
     [Lutz Jaenicke]

  *) IA-32 assembler support enhancements: unified ELF targets, support
     for SCO/Caldera platforms, fix for Cygwin shared build.
     [Andy Polyakov]

  *) Add support for FreeBSD on sparc64.  As a consequence, support for
     FreeBSD on non-x86 processors is separate from x86 processors on
     the config script, much like the NetBSD support.
     [Richard Levitte & Kris Kennaway <kris@obsecurity.org>]

 Changes between 0.9.6h and 0.9.7  [31 Dec 2002]

  [NB: OpenSSL 0.9.6i and later 0.9.6 patch levels were released after
  OpenSSL 0.9.7.]

  *) Fix session ID handling in SSLv2 client code: the SERVER FINISHED
     code (06) was taken as the first octet of the session ID and the last
     octet was ignored consequently. As a result SSLv2 client side session
     caching could not have worked due to the session ID mismatch between
     client and server.
     Behaviour observed by Crispin Flowerday <crispin@flowerday.cx> as
     PR #377.
     [Lutz Jaenicke]

  *) Change the declaration of needed Kerberos libraries to use EX_LIBS
     instead of the special (and badly supported) LIBKRB5.  LIBKRB5 is
     removed entirely.
     [Richard Levitte]

  *) The hw_ncipher.c engine requires dynamic locks.  Unfortunately, it
     seems that in spite of existing for more than a year, many application
     author have done nothing to provide the necessary callbacks, which
     means that this particular engine will not work properly anywhere.
     This is a very unfortunate situation which forces us, in the name
     of usability, to give the hw_ncipher.c a static lock, which is part
     of libcrypto.
     NOTE: This is for the 0.9.7 series ONLY.  This hack will never
     appear in 0.9.8 or later.  We EXPECT application authors to have
     dealt properly with this when 0.9.8 is released (unless we actually
     make such changes in the libcrypto locking code that changes will
     have to be made anyway).
     [Richard Levitte]

  *) In asn1_d2i_read_bio() repeatedly call BIO_read() until all content
     octets have been read, EOF or an error occurs. Without this change
     some truncated ASN1 structures will not produce an error.
     [Steve Henson]