CHANGES

 OpenSSL CHANGES
 _______________

 Changes between 0.9.6 and 0.9.7  [xx XXX 2000]

  *) Constify the cipher and digest 'method' functions and structures
     and modify related functions to take constant EVP_MD and EVP_CIPHER
     pointers.
     [Steve Henson]

  *) Implement ssl23_peek (analogous to ssl23_read), which previously
     did not exist.
     [Bodo Moeller]

  *) Replace rdtsc with _emit statements for VC++ version 5.
     [Jeremy Cooper <jeremy@baymoo.org>]

  *) Hide BN_CTX structure details in bn_lcl.h instead of publishing them
     in <openssl/bn.h>.  Also further increase BN_CTX_NUM to 24.
     [Bodo Moeller]

  *) Modify EVP_Digest*() routines so they now return values. Although the
     internal software routines can never fail additional hardware versions
     might.
     [Steve Henson]

  *) Clean up crypto/err/err.h and change some error codes to avoid conflicts:

     Previously ERR_R_FATAL was too small and coincided with ERR_LIB_PKCS7
     (= ERR_R_PKCS7_LIB); it is now 64 instead of 32.

     ASN1 error codes
          ERR_R_NESTED_ASN1_ERROR
          ...
          ERR_R_MISSING_ASN1_EOS
     were 4 .. 9, conflicting with
          ERR_LIB_RSA (= ERR_R_RSA_LIB)
          ...
          ERR_LIB_PEM (= ERR_R_PEM_LIB).
     They are now 58 .. 63 (i.e., just below ERR_R_FATAL).

     Add new error code 'ERR_R_INTERNAL_ERROR'.
     [Bodo Moeller]

  *) Don't overuse locks in crypto/err/err.c: For data retrieval, CRYPTO_r_lock
     suffices.
     [Bodo Moeller]

  *) New option '-subj arg' for 'openssl req' and 'openssl ca'.  This
     sets the subject name for a new request or supersedes the
     subject name in a given request. Formats that can be parsed are
          'CN=Some Name, OU=myOU, C=IT'
     and
          'CN=Some Name/OU=myOU/C=IT'.

     Add options '-batch' and '-verbose' to 'openssl req'.
     [Massimiliano Pala <madwolf@hackmasters.net>]

  *) Make it possible to reuse SSLv2 sessions.
     [Richard Levitte]

  *) Introduce the possibility to access global variables through
     functions on platform were that's the best way to handle exporting
     global variables in shared libraries.  To enable this functionality,
     one must configure with "EXPORT_VAR_AS_FN" or defined the C macro
     "OPENSSL_EXPORT_VAR_AS_FUNCTION" in crypto/opensslconf.h (the latter
     is normally done by Configure or something similar).

     To implement a global variable, use the macro OPENSSL_IMPLEMENT_GLOBAL
     in the source file (foo.c) like this:

	OPENSSL_IMPLEMENT_GLOBAL(int,foo)=1;
	OPENSSL_IMPLEMENT_GLOBAL(double,bar);

     To declare a global variable, use the macros OPENSSL_DECLARE_GLOBAL
     and OPENSSL_GLOBAL_REF in the header file (foo.h) like this:

	OPENSSL_DECLARE_GLOBAL(int,foo);
	#define foo OPENSSL_GLOBAL_REF(foo)
	OPENSSL_DECLARE_GLOBAL(double,bar);
	#define bar OPENSSL_GLOBAL_REF(bar)

     The #defines are very important, and therefore so is including the
     header file everywere where the defined globals are used.

     The macro OPENSSL_EXPORT_VAR_AS_FUNCTION also affects the definition
     of ASN.1 items, but that structure is a bt different.

     The largest change is in util/mkdef.pl which has been enhanced with
     better and easier to understand logic to choose which symbols should
     go into the Windows .def files as well as a number of fixes and code
     cleanup (among others, algorithm keywords are now sorted
     lexicographically to avoid constant rewrites).
     [Richard Levitte]

  *) In copy_email() check for >= 0 as a return value for
     X509_NAME_get_index_by_NID() since 0 is a valid index.
     [Steve Henson reported by Massimiliano Pala <madwolf@opensca.org>]

  *) In BN_div() keep a copy of the sign of 'num' before writing the
     result to 'rm' because if rm==num the value will be overwritten
     and produce the wrong result if 'num' is negative: this caused
     problems with BN_mod() and BN_nnmod().
     [Steve Henson]

  *) Function OCSP_request_verify(). This checks the signature on an
     OCSP request and verifies the signer certificate. The signer
     certificate is just checked for a generic purpose and OCSP request
     trust settings.
     [Steve Henson]

  *) Add OCSP_check_validity() function to check the validity of OCSP
     responses. OCSP responses are prepared in real time and may only
     be a few seconds old. Simply checking that the current time lies
     between thisUpdate and nextUpdate max reject otherwise valid responses
     caused by either OCSP responder or client clock innacuracy. Instead
     we allow thisUpdate and nextUpdate to fall within a certain period of
     the current time. The age of the response can also optionally be
     checked. Two new options -validity_period and -status_age added to
     ocsp utility.
     [Steve Henson]

  *) If signature or public key algorithm is unrecognized print out its
     OID rather that just UNKOWN.
     [Steve Henson]

  *) Avoid coredump with unsupported or invalid public keys by checking if
     X509_get_pubkey() fails in PKCS7_verify(). Fix memory leak when
     PKCS7_verify() fails with non detached data.
     [Steve Henson]

  *) Change OCSP_cert_to_id() to tolerate a NULL subject certificate and
     OCSP_cert_id_new() a NULL serialNumber. This allows a partial certificate
     ID to be generated from the issuer certificate alone which can then be
     passed to OCSP_id_issuer_cmp().
     [Steve Henson]

  *) New compilation option ASN1_ITEM_FUNCTIONS. This causes the new
     ASN1 modules to export functions returning ASN1_ITEM pointers
     instead of the ASN1_ITEM structures themselves. This adds several
     new macros which allow the underlying ASN1 function/structure to
     be accessed transparently. As a result code should not use ASN1_ITEM
     references directly (such as &X509_it) but instead use the relevant
     macros (such as ASN1_ITEM_rptr(X509)). This option is to allow
     use of the new ASN1 code on platforms where exporting structures
     is problematical (for example in shared libraries) but exporting
     functions returning pointers to structures is not.
     [Steve Henson]

  *) Add support for overriding the generation of SSL/TLS session IDs.
     These callbacks can be registered either in an SSL_CTX or per SSL.
     The purpose of this is to allow applications to control, if they wish,
     the arbitrary values chosen for use as session IDs, particularly as it
     can be useful for session caching in multiple-server environments. A
     command-line switch for testing this (and any client code that wishes
     to use such a feature) has been added to "s_server".
     [Geoff Thorpe, Lutz Jaenicke]

  *) Modify mkdef.pl to recognise and parse prprocessor conditionals
     of the form '#if defined(...) || defined(...) || ...' and
     '#if !defined(...) && !defined(...) && ...'.  This also avoids
     the growing number of special cases it was previously handling.
     [Richard Levitte]

  *) Don't use getenv in library functions when run as setuid/setgid.
     New function OPENSSL_issetugid().
     [Ulf Moeller]

  *) Make all configuration macros available for application by making
     sure they are available in opensslconf.h, by giving them names starting
     with "OPENSSL_" to avoid conflicts with other packages and by making
     sure e_os2.h will cover all platform-specific cases together with
     opensslconf.h.
     Additionally, it is now possible to define configuration/platform-
     specific names (called "system identities").  In the C code, these
     are prefixed with "OPENSSL_SYSNAME_".  e_os2.h will create another
     macro with the name beginning with "OPENSSL_SYS_", which is determined
     from "OPENSSL_SYSNAME_*" or compiler-specific macros depending on
     what is available.
     [Richard Levitte]

  *) New option -set_serial to 'req' and 'x509' this allows the serial
     number to use to be specified on the command line. Previously self
     signed certificates were hard coded with serial number 0 and the 
     CA options of 'x509' had to use a serial number in a file which was
     auto incremented.
     [Steve Henson]

  *) Avoid false positives in memory leak detection code (crypto/mem_dbg.c)
     due to incorrect handling of multi-threading:

     1. Fix timing glitch in the MemCheck_off() portion of CRYPTO_mem_ctrl().

     2. Fix logical glitch in is_MemCheck_on() aka CRYPTO_is_mem_check_on().

     3. Count how many times MemCheck_off() has been called so that
        nested use can be treated correctly.  This also avoids 
        inband-signalling in the previous code (which relied on the
        assumption that thread ID 0 is impossible).
     [Bodo Moeller]