passwd()/crypt() emulation incorrect

[John E. Malmberg]

Dave Jones <JONESD at er6s1.eng.ohio-state.edu> wrote:
> 
> The way the samba port emulates passwd()/crypt() functionality against the
> SYSUAF is wrong, you can't simply return a pointer to the VMS password
> hash quadword as the passwd string.  In traditional UNIX, the passwd()
> function returns a pointer to a null-terminated encoding of the password
> hash, the first 2 bytes of which are a 'salt' value.  The crypt() function
> takes the salt value and a candidate plain-text password to generate another 
> encoded string for comparsion (using strcmp()) with the original encoded 
> passwd string.   The raw binary string returned by the emulation routines
> can yield false positives if the hash has embedded zeros due to samba's
> use of strcmp() for the comparison
<snip>
> I placed a pwd.c in http://www.er6.eng.ohio-state.edu/~jonesd/samba/pwd.zip
> that returns valid ASCIZ strings for the passwd and crypt functions.
> The string encodes an extended salt so you don't have to assume the
> crypt() call refers to the most recent data returned by passwd().

The FRONTPORT library used by the SAMBA 2.0.6 port does this correctly.

It does use the cached data from the last call to passwd() for the 
username information.

I did not think of encoding the extra information in the passwd() call. 
  I will look at doing this.

The FRONTPORT library binaries, source and documentation can be found on 
the OpenVMS Freeware 5.0 CD-ROM.

The OpenVMS Freeware 5.0 CD-ROMs can be found on a link from the OpenVMS 
home page, http://www.openvms.compaq.com.

-John
wb8tyw at qsl.network
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