Re: Struggling with c functions

Many thanks to you!!!

It now works (did'nt realize that strings where not null
terminated) stupid me!!!

Regards,
On Sat, 28 Apr 2001, mlw wrote:

> You actually almost have it right.
>
> You are passing VARDATA(user) to crypt, this is wrong.
>
> You must do something like this:
>
> int ulen = VARSIZE(user)-VARHDRSZ;
> char utmp[ulen+]; // This works in newer GCC, cool.
> memcpy(utmp,VARDATA(user), len);
> utmp[ulen]=0;
> crypted=crypt(utmp,salt);
>
> Strings are not gurenteed to be NULL teminated.
>
>
> Olivier PRENANT wrote:
> >
> > Hi all,
> >
> > I'm rewriting my OLD crypt (Thanks to Henrique) C_fonction to version 0
> > forms :
> >
> > I have this C file compiled OK to a shared library:
> >
> > /*
> > *
> > * Henrique Pantarotto (scanner(at)cepa(dot)com(dot)br)
> > * Funcao para encriptar senhas (Function to encrypt passwords)
> > * September 1999
> > *
> > * PS: Note that all crypted passwords are created with salt "HP" (my name
> > * initials..) You can change that, or if you know C, you can do in a way
> > * that it will pick two random characters (the way it should really be).
> > *
> > */
> >
> > #include <strings.h>
> > #include <unistd.h>
> >
> > #include <postgres.h>
> >
> > text *post_crypt(text *user)
> > {
> > text *password;
> > char * crypt();
> > long now=time((long *) 0);
> > int len;
> > char salt[7]="PY", *crypted;
> > /*strcpy(salt,l64a(now));
> > salt[3]='\0'; */
> > crypted=crypt(VARDATA(user),salt);
> > len=strlen(crypted);
> > password= palloc((int32) 13 + VARHDRSZ);
> > VARATT_SIZEP(password)= (int32) VARHDRSZ + 13;
> > memcpy(VARDATA(password),crypted,len);
> > return password;
> > }
> >
> > text *sql_crypt(text *user,text *salt)
> > {
> > text *password;
> > char * crypt(), *crypted;
> > int len;
> > char s[3];
> > strncpy(s,VARDATA(salt),2);
> > s[2]='\0';
> > crypted=crypt(VARDATA(user),s);
> > len=strlen(crypted);
> > password=palloc((int32) 13 + VARHDRSZ);
> > VARATT_SIZEP(password)=(int32) 13 + VARHDRSZ;
> > memcpy(VARDATA(password),crypted,len);
> > return password;
> > }
> >
> > /*
> > Compile using something like this:
> >
> > gcc -I/home/postgres/postgresql-6.5.1/src/include -I/home/postgres/postgresql-6.5.1/src/backend -O2 -Wall -Wmissing-prototypes -fpic -I/home/postgres/postgresql-6.5.1/src/include -c -o encrypt.o encrypt.c
> > gcc -shared -o encrypt.so encrypt.o
> >
> > And last, you create the trigger in PostgreSQL using this:
> >
> > create function encrypt(text)
> > returns text as '/usr/local/pgsql/lib/encrypt.so' language 'c';
> >
> > If everything is okay, you'll probably have: select encrypt('secret') working
> > and showing:
> >
> > encrypt
> > ------------
> > HPK1Jt2NX21G.
> > (1 row)
> > */
> >
> > I have defined to SQL function:
> >
> > CREATE FUNCTION post_crypt(text) RETURNS text AS 'xxxx/encrypt.so'
> > CREATE FUNCTION sql_cypt(text,text) RETURNS text AS 'xxxx/encrypt.so';
> >
> > WHY on earth does
> >
> > SELECT post_crypt('test'),sql_crypt('test','PY')
> > NOT GIVE the same result???
> >
> > Please help,
> >
> > This is most urgent (My customer can't use this function anymore); it
> > worked OK with 7.0.3!!
> >
> > Regards,
> > --
> > Olivier PRENANT Tel: +33-5-61-50-97-00 (Work)
> > Quartier d'Harraud Turrou +33-5-61-50-97-01 (Fax)
> > 31190 AUTERIVE +33-6-07-63-80-64 (GSM)
> > FRANCE Email: ohp(at)pyrenet(dot)fr
> > ------------------------------------------------------------------------------
> > Make your life a dream, make your dream a reality. (St Exupery)
> >
> > ---------------------------(end of broadcast)---------------------------
> > TIP 6: Have you searched our list archives?
> >
> > http://www.postgresql.org/search.mpl
>
>

--
Olivier PRENANT Tel: +33-5-61-50-97-00 (Work)
Quartier d'Harraud Turrou +33-5-61-50-97-01 (Fax)
31190 AUTERIVE +33-6-07-63-80-64 (GSM)
FRANCE Email: ohp(at)pyrenet(dot)fr
------------------------------------------------------------------------------
Make your life a dream, make your dream a reality. (St Exupery)