Re: Re: Now for the VARDATA, VARSIZE, and VARHDRSZ stuff

Hello Brendan,

I too was having this problem, but now think that I am getting a very good
handle on these interfaces.

Being that you are trying to hash the standard unix crypt function to look over
the password file, I think that this solution might help you.

I have a simple an efficient C++ solution to this problem:

My "unixcrypt" functions now looks like this                                        
---------------------------------------------------------------
text *unix_encrypt(text *inarg, text *inpass)
{       char temp[25];       int temp_len;       // Take the "text" variables directly to the "strings"       string
instr(VARDATA(inarg),0,VARSIZE(inarg)-VARHDRSZ);      string passPhrase(VARDATA(inpass),0,VARSIZE(inpass)-VARHDRSZ);
  strcpy(temp,crypt(instr.c_str(),passPhrase.c_str()));       temp_len=strlen(temp);       string
outstr(temp,0,temp_len);              // Set up the outgoing DB "text" variable       int32      new_text_size =
outstr.size()+4;      text       *new_text = (text *) palloc(new_text_size);       memset((void *) new_text, 0,
new_text_size);      VARATT_SIZEP(new_text) = new_text_size;       // Move the variable over from the string
strncpy(VARDATA(new_text),outstr.c_str(),outstr.size());      return new_text;
 
}
----------------------------------------------------------------------------

Be sure to include the header:

#include <unistd.h>             // for unix crypt function  

---------------------------------------------------------------------------

hope that this helps,

Lonnie

--- Brendan Guenther <guenthe8@msu.edu> wrote:
> 
> 
> Peter Eisentraut wrote:
> 
> > The best things might be not to mess with this but call textin() and
> > textout() to convert your data to C strings.
> 
> I can't seem to find documentation for textin() and textout() can somebody
> point
> me in the right direction for this or provide an example.  I'm having similar
> problems that Lonnie is having with VARDATA and I think this might help.  I'm
> trying to link in a C function that makes use of OpenSSL's libcrypto
> functions.
> 
> Basically I just need to hash and verify passwords in the database, so as an
> alternate question, if I'm missing something and there is a better way to do
> password storage let me know.
> 
> Thanks,
> --
> Brendan Guenther
> guenthe8@msu.edu
> 
> 
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