/*      passwd.c - Password reading/hashing routines
        (c) 1989 Philip Zimmermann.  All rights reserved.
        Implemented in Microsoft C.
        Routines for getting a pass phrase from the user's console.
*/

#include        <stdio.h>       /* for fprintf() */
#include        <ctype.h>       /* for isdigit(), toupper(), etc. */
#include        <string.h>      /* for strlen() */

#include        "random.h"      /* for getstring() */
#include        "md5.h"
#include        "language.h"
#include        "pgp.h"
#include        "system.h"

#define MAXKEYLEN 254   /* max byte length of pass phrase */

boolean showpass = FALSE;

/*
**      hashpass - Hash pass phrase down to 128 bits (16 bytes).
**  keylen must be less than 1024.
**      Use the MD5 algorithm.
*/
void hashpass (char *keystring, int keylen, byte *hash)
{
        MD5_CTX mdContext;

        /* Calculate the hash */
        MD5Init(&mdContext);
        MD5Update(&mdContext, (unsigned char *) keystring, keylen);
        MD5Final(hash, &mdContext);
}       /* hashpass */


/*
**      GetHashedPassPhrase - get pass phrase from user, hashes it to an IDEA key.
        Parameters:
                returns char *keystring as the pass phrase itself
                return char *hash as the 16-byte hash of the pass phrase
                                using MD5.
                byte noecho:
                        0=ask once, echo.
                        1=ask once, no echo.
                        2=ask twice, no echo.
        Return 0 if no characters are input, else return 1.
        If we return 0, the hashed key will not be useful.
*/
int GetHashedPassPhrase(char *hash, boolean noecho)
{       char keystr1[MAXKEYLEN+2], keystr2[MAXKEYLEN+2];
        int len;

        if (showpass)
                noecho = 0;
        while (TRUE) {
                fprintf(pgpout,PSTR("\nEnter pass phrase: "));
#ifdef AMIGA
                requesterdesc = "Please enter pass phrase:";
#endif
                getstring(keystr1,MAXKEYLEN-1,!noecho);
                if (noecho<2)   /* no need to ask again if user can see it */
                        break;
                fprintf(pgpout,PSTR("\nEnter same pass phrase again: "));
                getstring(keystr2,MAXKEYLEN-1,!noecho);
                if (strcmp(keystr1,keystr2)==0)
                        break;
                fprintf(pgpout,PSTR("\n\007Error: Pass phrases were different.  Try again."));
                memset(keystr2, 0, sizeof(keystr2));
        }
#ifdef AMIGA
        requesterdesc = NULL;
#endif
        if (noecho && (filter_mode || quietmode))
                putc('\n', pgpout);

        len = strlen(keystr1);
        if (len == 0)
                return 0;
        /* We assume ASCII pass phrases, with no charset conversions. */
        /* This will have to change for EBCDIC */
        hashpass (keystr1, strlen(keystr1), (byte *) hash);
        memset(keystr1, 0, sizeof(keystr1));
        return 1;
}       /* GetHashedPassPhrase */