NAME

       ipsec_atoasr,  ipsec_rangetoa  -  convert  ASCII  to  Internet  address, subnet, or range,
       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                           IPSEC_ATOASR(3)