postgresql/contrib/chkpass/chkpass.c
2010-09-20 22:08:53 +02:00

160 lines
3.3 KiB
C

/*
* PostgreSQL type definitions for chkpass
* Written by D'Arcy J.M. Cain
* darcy@druid.net
* http://www.druid.net/darcy/
*
* contrib/chkpass/chkpass.c
* best viewed with tabs set to 4
*/
#include "postgres.h"
#include <time.h>
#include <unistd.h>
#ifdef HAVE_CRYPT_H
#include <crypt.h>
#endif
#include "fmgr.h"
#include "utils/builtins.h"
PG_MODULE_MAGIC;
/*
* This type encrypts it's input unless the first character is a colon.
* The output is the encrypted form with a leading colon. The output
* format is designed to allow dump and reload operations to work as
* expected without doing special tricks.
*/
/*
* This is the internal storage format for CHKPASSs.
* 15 is all I need but add a little buffer
*/
typedef struct chkpass
{
char password[16];
} chkpass;
/*
* Various forward declarations:
*/
Datum chkpass_in(PG_FUNCTION_ARGS);
Datum chkpass_out(PG_FUNCTION_ARGS);
Datum chkpass_rout(PG_FUNCTION_ARGS);
/* Only equal or not equal make sense */
Datum chkpass_eq(PG_FUNCTION_ARGS);
Datum chkpass_ne(PG_FUNCTION_ARGS);
/* This function checks that the password is a good one
* It's just a placeholder for now */
static int
verify_pass(const char *str)
{
return 0;
}
/*
* CHKPASS reader.
*/
PG_FUNCTION_INFO_V1(chkpass_in);
Datum
chkpass_in(PG_FUNCTION_ARGS)
{
char *str = PG_GETARG_CSTRING(0);
chkpass *result;
char mysalt[4];
static char salt_chars[] =
"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
/* special case to let us enter encrypted passwords */
if (*str == ':')
{
result = (chkpass *) palloc(sizeof(chkpass));
strlcpy(result->password, str + 1, 13 + 1);
PG_RETURN_POINTER(result);
}
if (verify_pass(str) != 0)
ereport(ERROR,
(errcode(ERRCODE_DATA_EXCEPTION),
errmsg("password \"%s\" is weak", str)));
result = (chkpass *) palloc(sizeof(chkpass));
mysalt[0] = salt_chars[random() & 0x3f];
mysalt[1] = salt_chars[random() & 0x3f];
mysalt[2] = 0; /* technically the terminator is not necessary
* but I like to play safe */
strcpy(result->password, crypt(str, mysalt));
PG_RETURN_POINTER(result);
}
/*
* CHKPASS output function.
* Just like any string but we know it is max 15 (13 plus colon and terminator.)
*/
PG_FUNCTION_INFO_V1(chkpass_out);
Datum
chkpass_out(PG_FUNCTION_ARGS)
{
chkpass *password = (chkpass *) PG_GETARG_POINTER(0);
char *result;
result = (char *) palloc(16);
result[0] = ':';
strcpy(result + 1, password->password);
PG_RETURN_CSTRING(result);
}
/*
* special output function that doesn't output the colon
*/
PG_FUNCTION_INFO_V1(chkpass_rout);
Datum
chkpass_rout(PG_FUNCTION_ARGS)
{
chkpass *password = (chkpass *) PG_GETARG_POINTER(0);
PG_RETURN_TEXT_P(cstring_to_text(password->password));
}
/*
* Boolean tests
*/
PG_FUNCTION_INFO_V1(chkpass_eq);
Datum
chkpass_eq(PG_FUNCTION_ARGS)
{
chkpass *a1 = (chkpass *) PG_GETARG_POINTER(0);
text *a2 = PG_GETARG_TEXT_PP(1);
char str[9];
text_to_cstring_buffer(a2, str, sizeof(str));
PG_RETURN_BOOL(strcmp(a1->password, crypt(str, a1->password)) == 0);
}
PG_FUNCTION_INFO_V1(chkpass_ne);
Datum
chkpass_ne(PG_FUNCTION_ARGS)
{
chkpass *a1 = (chkpass *) PG_GETARG_POINTER(0);
text *a2 = PG_GETARG_TEXT_PP(1);
char str[9];
text_to_cstring_buffer(a2, str, sizeof(str));
PG_RETURN_BOOL(strcmp(a1->password, crypt(str, a1->password)) != 0);
}