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NAME

       ipsec_atoasr - convert ASCII to Internet address, subnet, or range
       ipsec rangetoa - convert Internet address range to ASCII

SYNOPSIS

       #include <freeswan.h>

       const char *atoasr(const char *src, size_t srclen,
           char *type, struct in_addr *addrs);
       size_t rangetoa(struct in_addr *addrs, int format,
           char *dst, size_t dstlen);

DESCRIPTION

       These  functions  are obsolete; there is no current equivalent, because
       so far they have not proved useful.

       Atoasr converts an ASCII address,  subnet,  or  address  range  into  a
       suitable  combination  of  binary  addresses  (in  network byte order).
       Rangetoa converts an address  range  back  into  ASCII,  using  dotted-
       decimal  form  for  the  addresses  (the  other reverse conversions are
       handled by ipsec_addrtoa(3) and ipsec_subnettoa(3)).

       A single address can be any form acceptable to ipsec_atoaddr(3): dotted
       decimal,  DNS name, or hexadecimal number.  A subnet specification uses
       the form network/mask interpreted by ipsec_atosubnet(3).

       An address range is two ipsec_atoaddr(3) addresses separated by  a  ...
       delimiter.   If  there  are  four  dots rather than three, the first is
       taken as part of the begin address, e.g. for a complete DNS name  which
       ends  with  .  to suppress completion attempts.  The begin address of a
       range must be less than or equal to the end address.

       The srclen parameter of atoasr specifies the length of the ASCII string
       pointed  to by src; it is an error for there to be anything else (e.g.,
       a terminating NUL) within that length.   As  a  convenience  for  cases
       where  an  entire  NUL-terminated  string  is to be converted, a srclen
       value of 0 is taken to mean strlen(src).

       The type parameter of atoasr must point to  a  char  variable  used  to
       record  which form was found.  The addrs parameter must point to a two-
       element array of struct in_addr which receives the results.  The values
       stored into *type, and the corresponding values in the array, are:

                   *type   addrs[0]    addrs[1]

       address     ’a’     address     -
       subnet      ’s’     network     mask
       range       ’r’     begin       end

       The  dstlen  parameter  of  rangetoa  specifies  the  size  of  the dst
       parameter; under no circumstances are more than dstlen bytes written to
       dst.  A result which will not fit is truncated.  Dstlen can be zero, in
       which case dst need not be valid and no  result  is  written,  but  the
       return   value  is  unaffected;  in  all  other  cases,  the  (possibly
       truncated)  result  is  NUL-terminated.   The  freeswan.h  header  file
       defines  a  constant,  RANGETOA_BUF, which is the size of a buffer just
       large enough for worst-case results.

       The format parameter of rangetoa specifies what format is  to  be  used
       for  the  conversion.   The value 0 (not the ASCII character ’0’, but a
       zero value) specifies a reasonable default, and is  in  fact  the  only
       format  currently  available.  This parameter is a hedge against future
       needs.

       Atoasr returns NULL for success and a pointer to a string-literal error
       message  for  failure;  see  DIAGNOSTICS.   Rangetoa  returns  0  for a
       failure, and otherwise always returns the size of buffer which would be
       needed to accommodate the full conversion result, including terminating
       NUL; it is the caller’s responsibility to check this against  the  size
       of the provided buffer to determine whether truncation has occurred.

SEE ALSO

       ipsec_atoaddr(3), ipsec_atosubnet(3)

DIAGNOSTICS

       Fatal  errors  in atoasr are: empty input; error in ipsec_atoaddr(3) or
       ipsec_atosubnet(3) during conversion; begin address  of  range  exceeds
       end address.

       Fatal errors in rangetoa are: unknown format.

HISTORY

       Written for the FreeS/WAN project by Henry Spencer.

BUGS

       The  restriction  of  error reports to literal strings (so that callers
       don’t need to worry about freeing them or copying them) does limit  the
       precision of error reporting.

       The  error-reporting  convention lends itself to slightly obscure code,
       because many readers will not think of NULL as signifying  success.   A
       good way to make it clearer is to write something like:

              const char *error;

              error = atoasr( /* ... */ );
              if (error != NULL) {
                      /* something went wrong */

                                 11 June 2001