postgresql/contrib/chkpass/chkpass.c
2001-11-05 17:46:40 +00:00

193 lines
4.0 KiB
C

/*
* PostgreSQL type definitions for chkpass
* Written by D'Arcy J.M. Cain
* darcy@druid.net
* http://www.druid.net/darcy/
*
* $Id: chkpass.c,v 1.6 2001/11/05 17:46:22 momjian Exp $
* best viewed with tabs set to 4
*/
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <postgres.h>
#include <fmgr.h>
/*
* 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 bool random_initialized = false;
static char salt_chars[] =
"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
/* special case to let us enter encrypted passwords */
if (*str == ':')
{
result = (chkpass *) palloc(sizeof(chkpass));
strncpy(result->password, str + 1, 13);
result->password[13] = 0;
PG_RETURN_POINTER(result);
}
if (verify_pass(str) != 0)
{
elog(ERROR, "chkpass_in: purported CHKPASS \"%s\" is a weak password",
str);
PG_RETURN_POINTER(NULL);
}
result = (chkpass *) palloc(sizeof(chkpass));
if (!random_initialized)
{
srandom((unsigned int) time(NULL));
random_initialized = true;
}
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;
if (password == NULL)
PG_RETURN_POINTER(NULL);
if ((result = (char *) palloc(16)) != NULL)
{
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);
text *result = NULL;
if (password == NULL)
PG_RETURN_POINTER(NULL);
if ((result = (text *) palloc(VARHDRSZ + 16)) != NULL)
{
result->vl_len = VARHDRSZ + strlen(password->password);
memcpy(result->vl_dat, password->password, strlen(password->password));
}
PG_RETURN_CSTRING(result);
}
/*
* Boolean tests
*/
PG_FUNCTION_INFO_V1(chkpass_eq)
Datum
chkpass_eq(PG_FUNCTION_ARGS)
{
chkpass *a1 = (chkpass *) PG_GETARG_POINTER(0);
text *a2 = (text *) PG_GETARG_TEXT_P(1);
char str[10];
int sz = 8;
if (!a1 || !a2)
PG_RETURN_BOOL(0);
if (a2->vl_len < 12)
sz = a2->vl_len - 4;
strncpy(str, a2->vl_dat, sz);
str[sz] = 0;
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 = (text *) PG_GETARG_TEXT_P(1);
char str[10];
int sz = 8;
if (!a1 || !a2)
PG_RETURN_BOOL(0);
if (a2->vl_len < 12)
sz = a2->vl_len - 4;
strncpy(str, a2->vl_dat, sz);
str[sz] = 0;
PG_RETURN_BOOL(strcmp(a1->password, crypt(str, a1->password)) != 0);
}