Merge ext-conf.txt and buffer.txt into a global openssl.txt because we

BUFFER Library.

[Note: I wrote this when I saw a Malloc version of strdup() in there which

 I'd written myself anyway. I was so annoyed at not noticing this I decided to

 document it :-) Steve.]

The buffer library handles simple character arrays. Buffers are used for various

purposes in the library, most notably memory BIOs.

The library uses the BUF_MEM structure defined in buffer.h:

typedef struct buf_mem_st

        {

        int length;     /* current number of bytes */

        char *data;

        int max;        /* size of buffer */

        } BUF_MEM;

'length' is the current size of the buffer in bytes, 'max' is the amount of

memory allocated to the buffer. There are three functions which handle these

and one "miscelanous" function.

BUF_MEM *BUF_MEM_new()

This allocates a new buffer of zero size. Returns the buffer or NULL on error.

void BUF_MEM_free(BUF_MEM *a)

This frees up an already existing buffer. The data is zeroed before freeing

up in case the buffer contains sensitive data.

int BUF_MEM_grow(BUF_MEM *str, int len)

This changes the size of an already existing buffer. It returns zero on error

or the new size (i.e. 'len'). Any data already in the buffer is preserved if

it increases in size.

char * BUF_strdup(char *str)

This is the previously mentioned strdup function: like the standard library

strdup() it copies a null terminated string into a block of allocated memory

and returns a pointer to the allocated block.

Unlike the standard C library strdup() this function uses Malloc() and so

should be used in preference to the standard library strdup() because it can

be used for memory leak checking or replacing the malloc() function.

The memory allocated from BUF_strdup() should be freed up using the Free()

function.

This is some preliminary documentation for OpenSSL.

==============================================================================

                            BUFFER Library

==============================================================================

[Note: I wrote this when I saw a Malloc version of strdup() in there which

 I'd written myself anyway. I was so annoyed at not noticing this I decided to

 document it :-) Steve.]

The buffer library handles simple character arrays. Buffers are used for various

purposes in the library, most notably memory BIOs.

The library uses the BUF_MEM structure defined in buffer.h:

typedef struct buf_mem_st

        {

        int length;     /* current number of bytes */

        char *data;

        int max;        /* size of buffer */

        } BUF_MEM;

'length' is the current size of the buffer in bytes, 'max' is the amount of

memory allocated to the buffer. There are three functions which handle these

and one "miscelanous" function.

BUF_MEM *BUF_MEM_new()

This allocates a new buffer of zero size. Returns the buffer or NULL on error.

void BUF_MEM_free(BUF_MEM *a)

This frees up an already existing buffer. The data is zeroed before freeing

up in case the buffer contains sensitive data.

int BUF_MEM_grow(BUF_MEM *str, int len)

This changes the size of an already existing buffer. It returns zero on error

or the new size (i.e. 'len'). Any data already in the buffer is preserved if

it increases in size.

char * BUF_strdup(char *str)

This is the previously mentioned strdup function: like the standard library

strdup() it copies a null terminated string into a block of allocated memory

and returns a pointer to the allocated block.

Unlike the standard C library strdup() this function uses Malloc() and so

should be used in preference to the standard library strdup() because it can

be used for memory leak checking or replacing the malloc() function.

The memory allocated from BUF_strdup() should be freed up using the Free()

function.

==============================================================================

               OpenSSL X509V3 extension configuration

==============================================================================

OpenSSL X509V3 extension configuration: preliminary documentation.

INTRODUCTION.

Some extensions are only partially supported and currently are only displayed

but cannot be set. These include private key usage period, CRL number, and

CRL reason.