X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=FAQ;h=463bc1e139668685b19e2d41f03e110fa9976aa5;hp=1b129bc5ac8bbf977ff5a8246f1a6a568f001f21;hb=10f92aac33de06d3bf0515b0e54bf282746113aa;hpb=500df82a96fa9a1105a0da6367a9fc0e9c909715

diff --git a/FAQ b/FAQ
index 1b129bc5ac..463bc1e139 100644
--- a/FAQ
+++ b/FAQ
@@ -52,6 +52,7 @@ OpenSSL  -  Frequently Asked Questions
 * Is OpenSSL thread-safe?
 * I've compiled a program under Windows and it crashes: why?
 * How do I read or write a DER encoded buffer using the ASN1 functions?
+* OpenSSL uses DER but I need BER format: does OpenSSL support BER?
 * I've tried using <M_some_evil_pkcs12_macro> and I get errors why?
 * I've called <some function> and it fails, why?
 * I just get a load of numbers for the error output, what do they mean?
@@ -60,6 +61,7 @@ OpenSSL  -  Frequently Asked Questions
 * Can I use OpenSSL's SSL library with non-blocking I/O?
 * Why doesn't my server application receive a client certificate?
 * Why does compilation fail due to an undefined symbol NID_uniqueIdentifier?
+* I think I've detected a memory leak, is this a bug?
 
 ===============================================================================
 
@@ -68,7 +70,7 @@ OpenSSL  -  Frequently Asked Questions
 * Which is the current version of OpenSSL?
 
 The current version is available from <URL: http://www.openssl.org>.
-OpenSSL 0.9.7a was released on February 19, 2003.
+OpenSSL 0.9.7e was released on October 25, 2004.
 
 In addition to the current stable release, you can also access daily
 snapshots of the OpenSSL development version at <URL:
@@ -116,11 +118,14 @@ OpenSSL.  Information on the OpenSSL mailing lists is available from
 
 * Where can I get a compiled version of OpenSSL?
 
+You can finder pointers to binary distributions in
+http://www.openssl.org/related/binaries.html .
+
 Some applications that use OpenSSL are distributed in binary form.
 When using such an application, you don't need to install OpenSSL
 yourself; the application will include the required parts (e.g. DLLs).
 
-If you want to install OpenSSL on a Windows system and you don't have
+If you want to build OpenSSL on a Windows system and you don't have
 a C compiler, read the "Mingw32" section of INSTALL.W32 for information
 on how to obtain and install the free GNU C compiler.
 
@@ -646,26 +651,26 @@ built OpenSSL with /MD your application must use /MD and cannot use /MDd.
 * How do I read or write a DER encoded buffer using the ASN1 functions?
 
 You have two options. You can either use a memory BIO in conjunction
-with the i2d_XXX_bio() or d2i_XXX_bio() functions or you can use the
-i2d_XXX(), d2i_XXX() functions directly. Since these are often the
+with the i2d_*_bio() or d2i_*_bio() functions or you can use the
+i2d_*(), d2i_*() functions directly. Since these are often the
 cause of grief here are some code fragments using PKCS7 as an example:
 
-unsigned char *buf, *p;
-int len;
+ unsigned char *buf, *p;
+ int len;
 
-len = i2d_PKCS7(p7, NULL);
-buf = OPENSSL_malloc(len); /* or Malloc, error checking omitted */
-p = buf;
-i2d_PKCS7(p7, &p);
+ len = i2d_PKCS7(p7, NULL);
+ buf = OPENSSL_malloc(len); /* or Malloc, error checking omitted */
+ p = buf;
+ i2d_PKCS7(p7, &p);
 
 At this point buf contains the len bytes of the DER encoding of
 p7.
 
 The opposite assumes we already have len bytes in buf:
 
-unsigned char *p;
-p = buf;
-p7 = d2i_PKCS7(NULL, &p, len);
+ unsigned char *p;
+ p = buf;
+ p7 = d2i_PKCS7(NULL, &p, len);
 
 At this point p7 contains a valid PKCS7 structure of NULL if an error
 occurred. If an error occurred ERR_print_errors(bio) should give more
@@ -680,6 +685,20 @@ and attempts to free the buffer will have unpredictable results
 because it no longer points to the same address.
 
 
+* OpenSSL uses DER but I need BER format: does OpenSSL support BER?
+
+The short answer is yes, because DER is a special case of BER and OpenSSL
+ASN1 decoders can process BER.
+
+The longer answer is that ASN1 structures can be encoded in a number of
+different ways. One set of ways is the Basic Encoding Rules (BER) with various
+permissible encodings. A restriction of BER is the Distinguished Encoding
+Rules (DER): these uniquely specify how a given structure is encoded.
+
+Therefore, because DER is a special case of BER, DER is an acceptable encoding
+for BER.
+
+
 * I've tried using <M_some_evil_pkcs12_macro> and I get errors why?
 
 This usually happens when you try compiling something using the PKCS#12
@@ -762,5 +781,17 @@ The correct name according to RFC2256 (LDAP) is x500UniqueIdentifier.
 Change your code to use the new name when compiling against OpenSSL 0.9.7.
 
 
+* I think I've detected a memory leak, is this a bug?
+
+In most cases the cause of an apparent memory leak is an OpenSSL internal table
+that is allocated when an application starts up. Since such tables do not grow
+in size over time they are harmless.
+
+These internal tables can be freed up when an application closes using various
+functions.  Currently these include: EVP_cleanup(), ERR_remove_state(),
+ERR_free_strings(), ENGINE_cleanup(), CONF_modules_unload() and
+CRYPTO_cleanup_all_ex_data().
+
+
 ===============================================================================