ber_alloc_t,    ber_flush,    ber_flush2,    ber_printf,   ber_put_int,
   ber_put_enum,    ber_put_ostring,     ber_put_string,     ber_put_null,
   ber_put_boolean,   ber_put_bitstring,   ber_start_seq,   ber_start_set,
   ber_put_seq, ber_put_set -  OpenLDAP  LBER  simplified  Basic  Encoding
   Rules library routines for encoding


   OpenLDAP LBER (liblber, -llber)


   #include <lber.h>

   BerElement *ber_alloc_t(int options);

   int ber_flush(Sockbuf *sb, BerElement *ber, int freeit);

   int ber_flush2(Sockbuf *sb, BerElement *ber, int freeit);

   int ber_printf(BerElement *ber, const char *fmt, ...);

   int ber_put_int(BerElement *ber, ber_int_t num, ber_tag_t tag);

   int ber_put_enum(BerElement *ber, ber_int_t num, ber_tag_t tag);

   int  ber_put_ostring(BerElement  *ber,  const char *str, ber_len_t len,
   ber_tag_t tag);

   int ber_put_string(BerElement *ber, const char *str, ber_tag_t tag);

   int ber_put_null(BerElement *ber, ber_tag_t tag);

   int ber_put_boolean(BerElement *ber, ber_int_t bool, ber_tag_t tag);

   int ber_put_bitstring(BerElement *ber, const char *str, ber_len_t blen,
   ber_tag_t tag);

   int ber_start_seq(BerElement *ber, ber_tag_t tag);

   int ber_start_set(BerElement *ber, ber_tag_t tag);

   int ber_put_seq(BerElement *ber);

   int ber_put_set(BerElement *ber);


   These   routines   provide  a  subroutine  interface  to  a  simplified
   implementation of the Basic Encoding Rules of ASN.1.   The  version  of
   BER  these  routines  support is the one defined for the LDAP protocol.
   The encoding rules are the same as BER, except that only definite  form
   lengths  are  used, and bitstrings and octet strings are always encoded
   in primitive form.  This man page describes the  encoding  routines  in
   the  lber library.  See lber-decode(3) for details on the corresponding
   decoding routines.  Consult lber-types(3) for information about  types,
   allocators, and deallocators.

   Normally,  the  only  routines that need to be called by an application
   are ber_alloc_t() to allocate a BER element for encoding,  ber_printf()
   to  do  the  actual  encoding,  and  ber_flush2() to actually write the
   element.  The other routines are provided for those  applications  that
   need  more  control  than  ber_printf()  provides.   In  general, these
   routines return the length of the element encoded, or -1  if  an  error

   The  ber_alloc_t()  routine  is used to allocate a new BER element.  It
   should be called with an argument of LBER_USE_DER.

   The ber_flush2() routine is used to actually write  the  element  to  a
   socket  (or  file)  descriptor,  once  it has been fully encoded (using
   ber_printf() and friends).  See lber-sockbuf(3) for more details on the
   Sockbuf implementation of the sb parameter.  If the freeit parameter is
   non-zero,    the    supplied     ber     will     be     freed.      If
   LBER_FLUSH_FREE_ON_SUCCESS   is  used,  the  ber  is  only  freed  when
   successfully   flushed,   otherwise   it    is    left    intact;    if
   LBER_FLUSH_FREE_ON_ERROR  is  used, the ber is only freed when an error
   occurs, otherwise it is left intact; if LBER_FLUSH_FREE_ALWAYS is used,
   the  ber  is  freed  anyway.   This  function differs from the original
   ber_flush(3) function, whose behavior corresponds to that indicated for
   LBER_FLUSH_FREE_ON_SUCCESS.   Note  that in the future, the behavior of
   ber_flush(3)  with  freeit  non-zero  might   change   into   that   of
   ber_flush2(3) with freeit set to LBER_FLUSH_FREE_ALWAYS.

   The  ber_printf()  routine  is used to encode a BER element in much the
   same way that sprintf(3) works.  One important difference,  though,  is
   that  some  state  information  is  kept with the ber parameter so that
   multiple calls can be made to ber_printf() to append things to the  end
   of  the  BER  element.   Ber_printf()  writes  to  ber,  a pointer to a
   BerElement such  as  returned  by  ber_alloc_t().   It  interprets  and
   formats  its  arguments according to the format string fmt.  The format
   string can contain the following characters:

          b  Boolean.  An  ber_int_t  parameter  should  be  supplied.   A
             boolean element is output.

          e  Enumeration.   An ber_int_t parameter should be supplied.  An
             enumeration element is output.

          i  Integer.  An ber_int_t  parameter  should  be  supplied.   An
             integer element is output.

          B  Bitstring.  A char * pointer to the start of the bitstring is
             supplied, followed by the number of bits in the bitstring.  A
             bitstring element is output.

          n  Null.  No parameter is required.  A null element is output.

          o  Octet  string.   A char * is supplied, followed by the length
             of the string pointed to.  An octet string element is output.

          O  Octet string.  A struct  berval  *  is  supplied.   An  octet
             string element is output.

          s  Octet  string.   A  null-terminated  string  is supplied.  An
             octet string element is output, not  including  the  trailing
             NULL octet.

          t  Tag.  A ber_tag_t specifying the tag to give the next element
             is provided.  This works across calls.

          v  Several octet strings.  A null-terminated array of  char  *'s
             is supplied.  Note that a construct like '{v}' is required to
             get an actual SEQUENCE OF octet strings.

          V  Several octet strings.  A  null-terminated  array  of  struct
             berval  *'s is supplied.  Note that a construct like '{V}' is
             required to get an actual SEQUENCE OF octet strings.

          W  Several octet  strings.   An  array  of  struct  berval's  is
             supplied.   The array is terminated by a struct berval with a
             NULL bv_val.  Note that a construct like '{W}' is required to
             get an actual SEQUENCE OF octet strings.

          {  Begin sequence.  No parameter is required.

          }  End sequence.  No parameter is required.

          [  Begin set.  No parameter is required.

          ]  End set.  No parameter is required.

   The  ber_put_int()  routine  writes  the integer element num to the BER
   element ber.

   The ber_put_enum() routine writes the enumeration element  num  to  the
   BER element ber.

   The ber_put_boolean() routine writes the boolean value given by bool to
   the BER element.

   The ber_put_bitstring() routine writes blen bits starting at str  as  a
   bitstring value to the given BER element.  Note that blen is the length
   in bits of the bitstring.

   The ber_put_ostring() routine writes len bytes starting at str  to  the
   BER element as an octet string.

   The  ber_put_string()  routine writes the null-terminated string (minus
   the terminating ' ') to the BER element as an octet string.

   The ber_put_null() routine writes a NULL element to the BER element.

   The ber_start_seq() routine is used to start  a  sequence  in  the  BER
   element.   The ber_start_set() routine works similarly.  The end of the
   sequence or set is marked by the nearest matching call to ber_put_seq()
   or ber_put_set(), respectively.


   Assuming  the  following  variable declarations, and that the variables
   have been assigned appropriately, an lber  encoding  of  the  following
   ASN.1 object:

         AlmostASearchRequest := SEQUENCE {
             baseObject      DistinguishedName,
             scope           ENUMERATED {
                 baseObject    (0),
                 singleLevel   (1),
                 wholeSubtree  (2)
             derefAliases    ENUMERATED {
                 neverDerefaliases   (0),
                 derefInSearching    (1),
                 derefFindingBaseObj (2),
                 alwaysDerefAliases  (3)
             sizelimit       INTEGER (0 .. 65535),
             timelimit       INTEGER (0 .. 65535),
             attrsOnly       BOOLEAN,
             attributes      SEQUENCE OF AttributeType

   can be achieved like so:

         int rc;
         ber_int_t    scope, ali, size, time, attrsonly;
         char   *dn, **attrs;
         BerElement *ber;

         /* ... fill in values ... */

         ber = ber_alloc_t( LBER_USE_DER );

         if ( ber == NULL ) {
                 /* error */

         rc = ber_printf( ber, "{siiiib{v}}", dn, scope, ali,
             size, time, attrsonly, attrs );

         if( rc == -1 ) {
                 /* error */
         } else {
                 /* success */


   If an error occurs during encoding, generally these routines return -1.


   The  return  values  for  all  of  these  functions are declared in the
   <lber.h> header file.


   lber-decode(3), lber-memory(3), lber-sockbuf(3), lber-types(3)


   OpenLDAP Software is developed and maintained by The  OpenLDAP  Project
   <>.    OpenLDAP   Software   is   derived  from
   University of Michigan LDAP 3.3 Release.


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