ckuath.c

C-Kermit源码。是使用串口/Modem和网络通讯的程序

        g_kstream->encrypt(&i, NULL);
#ifdef DEBUG
        hexdump("to cyphertext", s, n);
#endif
    }
    else debug(F101,"ck_tn_encrypt not encrypting","",n);
#endif /* ENCRYPTION */
}

/*  C K _ K R B _ D E C R Y P T
 *  decrypts n characters in s if we are decrypting
 */

VOID
#ifdef CK_ANSIC
ck_tn_decrypt( char * s, int n )
#else
ck_tn_decrypt( s,n ) char * s; int n;
#endif
{
#ifdef CK_ENCRYPTION
    struct kstream_data_block i;

    if (g_kstream->decrypt && encrypt_is_decrypting()) {

#ifdef DEBUG
        hexdump("from cyphertext", s, n);
#endif

        i.ptr = s;
        i.length = n;
        g_kstream->decrypt(&i, NULL);
#ifdef DEBUG
        hexdump("to plaintext", s, n);
#endif
    }
    else debug(F101,"ck_tn_decrypt not decrypting","",n);
#endif /* ENCRYPTION */
}

/*  S E N D K 5 A U T H S B
 *  Send a Kerberos 5 Authentication Subnegotiation to host and
 *  output appropriate Telnet Debug messages
 *
 *  type - Sub Negotiation type
 *  data - ptr to buffer containing data
 *  len  - len of buffer if not NUL terminated
 *
 *  returns number of characters sent or error value
 */

static int
#ifdef CK_ANSIC
SendK5AuthSB(int type, void *data, int len)
#else
SendK5AuthSB(type,data,len) int type; void *data; int len;
#endif
{
    int rc;
    unsigned char *p = str_data + 3;
    unsigned char *cd = (unsigned char *)data;
    extern int sstelnet;

#ifdef CK_SSL
    if (TELOPT_SB(TELOPT_START_TLS).start_tls.me_follows) {
        if (ttchk() < 0)
	  return(0);
        else
	  return(1);
    }
#endif /* CK_SSL */

    if ( type < 0 || type > 6 )         /* Check for invalid values */
        return(0);

    if (!cd) {
        cd = (unsigned char *)"";
        len = 0;
    }

    if (len == -1)                        /* Use strlen() for len */
        len = strlen((char *)cd);

    /* Construct Message */
    *p++ = sstelnet ? TELQUAL_REPLY : TELQUAL_IS;
    *p++ = AUTHTYPE_KERBEROS_V5;
    *p = AUTH_CLIENT_TO_SERVER;
    *p |= auth_how;
#ifdef CK_ENCRYPTION
    *p |= auth_crypt;
#endif
#ifdef USE_INI_CRED_FWD
    if (auth_fwd)
        *p |= INI_CRED_FWD_ON;
#endif /* USE_INI_CRED_FWD */
    p++;
    *p++ = type;
    while (len-- > 0) {
        if ((*p++ = *cd++) == IAC)
            *p++ = IAC;
    }
    *p++ = IAC;
    *p++ = SE;

    /* Handle Telnet Debugging Messages */
    if (deblog || tn_deb || debses) {
        int i;
        int deblen=p-str_data-2;
        char *s=NULL;
        int mode = AUTH_CLIENT_TO_SERVER | (auth_how & AUTH_HOW_MASK) |
            (auth_crypt?AUTH_ENCRYPT_USING_TELOPT:AUTH_ENCRYPT_OFF)
#ifdef USE_INI_CRED_FWD
              | (auth_fwd?INI_CRED_FWD_ON:INI_CRED_FWD_OFF)
#endif /* USE_INI_CRED_FWD */
                    ;

        switch (type) {
        case 0:
            s = "AUTH";
            break;
        case 1:
            s = "REJECT";
            break;
        case 2:
            s = "ACCEPT";
            break;
        case 3:
            s = "RESPONSE";
            break;
        case 4:
            s = "FORWARD";
            break;
        case 5:
            s = "FORWARD_ACCEPT";
            break;
        case 6:
            s = "FORWARD_REJECT";
            break;
        }

	sprintf(tn_msg,"TELNET SENT SB %s %s %s %s %s ",
                 TELOPT(TELOPT_AUTHENTICATION),
                 str_data[3] == TELQUAL_IS ? "IS" :
                 str_data[3] == TELQUAL_REPLY ? "REPLY" : "???",
                 authtype_names[authentication_version],
                 authmode_names[mode],
                 s);
#ifdef HEXDISP
        {
            int was_hex = 1;
            for ( i=7;i<deblen;i++ ) {
                if ( str_data[i] < 32 || str_data[i] >= 127) {
                    sprintf(hexbuf,"%s%02X ",was_hex?"":"\" ",str_data[i]);
                    was_hex = 1;
                } else {
                    sprintf(hexbuf,"%s%c",was_hex?"\"":"",str_data[i]);
                    was_hex = 0;
                }
                strcat(tn_msg,hexbuf);
            }
            if ( !was_hex )
                strcat(tn_msg,"\" ");
        }
#else /* HEXDISP */
        memcpy(hexbuf,&str_data[7],deblen-7);
        hexbuf[deblen-7] = ' ';
        hexbuf[deblen-6] = '\0';
        strcat(tn_msg,hexbuf);
#endif /* HEXDISP */
        strcat(tn_msg,"IAC SE");
	debug(F100,tn_msg,"",0);
	if (tn_deb || debses) tn_debug(tn_msg);
    }

    /* Send data */
    rc = ttol((CHAR *)str_data, p - str_data);
    debug(F111,"SendK5AuthSB","ttol()",rc);
    return(rc);
}

/*  S E N D K 4 A U T H S B
 *  Send a Kerberos 4 Authentication Subnegotiation to host and
 *  output appropriate Telnet Debug messages
 *
 *  type - Sub Negotiation type
 *  data - ptr to buffer containing data
 *  len  - len of buffer if not NUL terminated
 *
 *  returns number of characters sent or error value
 */

static int
#ifdef CK_ANSIC
SendK4AuthSB(int type, void *data, int len)
#else
SendK4AuthSB(type,data,len) int type; void *data; int len;
#endif
{
    int rc;
    unsigned char *p = str_data + 3;
    unsigned char *cd = (unsigned char *)data;
    extern int sstelnet;
    int mode = (auth_how & AUTH_HOW_MASK) |
        (auth_crypt?AUTH_ENCRYPT_USING_TELOPT:AUTH_ENCRYPT_OFF) ;

    if ( type < 0 || type > 4 )         /* Check for invalid values */
        return(0);

#ifdef CK_SSL
    if (TELOPT_SB(TELOPT_START_TLS).start_tls.me_follows) {
        if (ttchk() < 0)
	  return(0);
        else
	  return(1);
    }
#endif /* CK_SSL */

    if (!cd) {
        cd = (unsigned char *)"";
        len = 0;
    }

    if (len == -1)                        /* Use strlen() for len */
        len = strlen((char *)cd);


    /* Construct Message */
    *p++ = sstelnet ? TELQUAL_REPLY : TELQUAL_IS;
    *p++ = AUTHTYPE_KERBEROS_V4;
    *p = AUTH_CLIENT_TO_SERVER;
    *p |= mode;
    p++;
    *p++ = type;
    while (len-- > 0) {
        if ((*p++ = *cd++) == IAC)
            *p++ = IAC;
        }
    *p++ = IAC;
    *p++ = SE;

    /* Handle Telnet Debugging Messages */
    if (deblog || tn_deb || debses) {
        int i;
        int deblen=p-str_data-2;
        char *s=NULL;

        switch (type) {
        case 0:
            s = "AUTH";
            break;
        case 1:
            s = "REJECT";
            break;
        case 2:
            s = "ACCEPT";
            break;
        case 3:
            s = "CHALLENGE";
            break;
        case 4:
            s = "RESPONSE";
            break;
        }

	sprintf(tn_msg,"TELNET SENT SB %s %s %s %s %s ",
                 TELOPT(TELOPT_AUTHENTICATION),
                 str_data[3] == TELQUAL_IS ? "IS" :
                 (str_data[3] == TELQUAL_REPLY ? "REPLY" : "???"),
                 authtype_names[authentication_version],
                 authmode_names[mode],
                 s);
#ifdef HEXDISP
        {
            int was_hex = 1;
            for ( i=7;i<deblen;i++ ) {
                if ( str_data[i] < 32 || str_data[i] >= 127) {
                    sprintf(hexbuf,"%s%02X ",was_hex?"":"\" ",str_data[i]);
                    was_hex = 1;
                } else {
                    sprintf(hexbuf,"%s%c",was_hex?"\"":"",str_data[i]);
                    was_hex = 0;
                }
                strcat(tn_msg,hexbuf);
            }
            if ( !was_hex )
                strcat(tn_msg,"\" ");
        }
#else /* HEXDISP */
        memcpy(hexbuf,&str_data[7],deblen-7);
        hexbuf[deblen-7] = ' ';
        hexbuf[deblen-6] = '\0';
        strcat(tn_msg,hexbuf);
#endif /* HEXDISP */
        strcat(tn_msg,"IAC SE");
	debug(F100,tn_msg,"",0);
	if (tn_deb || debses) tn_debug(tn_msg);
    }

    /* Send data */
    rc = ttol((CHAR *)str_data, p - str_data);
    debug(F111,"SendK4AuthSB","ttol()",rc);
    return(rc);
}

/*  S E N D S R P A U T H S B
 *  Send a SRP Authentication Subnegotiation to host and
 *  output appropriate Telnet Debug messages
 *
 *  type - Sub Negotiation type
 *  data - ptr to buffer containing data
 *  len  - len of buffer if not NUL terminated
 *
 *  returns number of characters sent or error value
 */

static int
#ifdef CK_ANSIC
SendSRPAuthSB(int type, void *data, int len)
#else
SendSRPAuthSB(type,data,len) int type; void *data; int len;
#endif
{
    int rc;
    unsigned char *p = str_data + 3;
    unsigned char *cd = (unsigned char *)data;
    extern int sstelnet;

    /* Check for invalid values */
    if ( type != SRP_EXP && type != SRP_RESPONSE &&
         type != SRP_REJECT && type != SRP_ACCEPT &&
         type != SRP_CHALLENGE && type != SRP_PARAMS &&
         type != SRP_AUTH)
        return(0);

    if (len == -1)                        /* Use strlen() for len */
        len = strlen((char *)cd);

    /* Construct Message */
    *p++ = sstelnet ? TELQUAL_REPLY : TELQUAL_IS;
    *p++ = AUTHTYPE_SRP;
    *p = AUTH_CLIENT_TO_SERVER;
    *p |= auth_how;
#ifdef CK_ENCRYPTION
    *p |= auth_crypt;
#endif
    p++;
    *p++ = type;
    while (len-- > 0) {
        if ((*p++ = *cd++) == IAC)
            *p++ = IAC;
        }
    *p++ = IAC;
    *p++ = SE;

    /* Handle Telnet Debugging Messages */
    if (deblog || tn_deb || debses) {
        int i;
        int deblen=p-str_data-2;
        char *s=NULL;
        int mode = AUTH_CLIENT_TO_SERVER | (auth_how & AUTH_HOW_MASK) |
            (auth_crypt?AUTH_ENCRYPT_USING_TELOPT:AUTH_ENCRYPT_OFF);

        switch (type) {
        case 0:
            s = "AUTH";
            break;
        case 1:
            s = "REJECT";
            break;
        case 2:
            s = "ACCEPT";
            break;
        case 3:
            s = "CHALLENGE";
            break;
        case 4:
            s = "RESPONSE";
            break;
        case 5:
            s = "FORWARD";
            break;
        case 6:
            s = "FORWARD_ACCEPT";
            break;
        case 7:
            s = "FORWARD_REJECT";
            break;
        case 8:
            s = "EXP";
            break;
        case 9:
            s = "PARAMS";
            break;
        }

	sprintf(tn_msg,"TELNET SENT SB %s %s %s %s %s ",
                 TELOPT(TELOPT_AUTHENTICATION),
                 str_data[3] == TELQUAL_REPLY ? "REPLY" :
                 str_data[3] == TELQUAL_IS ? "IS" : "???",
                 authtype_names[authentication_version],
                 authmode_names[mode],
                 s);
#ifdef HEXDISP
        {
            int was_hex = 1;
            for ( i=7;i<deblen;i++ ) {
                if ( str_data[i] < 32 || str_data[i] >= 127) {
                    sprintf(hexbuf,"%s%02X ",was_hex?"":"\" ",str_data[i]);
                    was_hex = 1;
                } else {
                    sprintf(hexbuf,"%s%c",was_hex?"\"":"",str_data[i]);
                    was_hex = 0;
                }
                strcat(tn_msg,hexbuf);
            }
            if ( !was_hex )
                strcat(tn_msg,"\" ");
        }
#else /* HEXDISP */
        memcpy(hexbuf,&str_data[7],deblen-7);
        hexbuf[deblen-7] = ' ';
        hexbuf[deblen-6] = '\0';
        strcat(tn_msg,hexbuf);
#endif /* HEXDISP */
        strcat(tn_msg,"IAC SE");
	debug(F100,tn_msg,"",0);
	if (tn_deb || debses) tn_debug(tn_msg);
    }

    /* Send data */
    rc = ttol((CHAR *)str_data, p - str_data);
    return(rc);
}

#ifdef CK_ENCRYPTION
/*
 * Function: Enable or disable the encryption process.
 *
 * Parameters:
 *	enable - TRUE to enable, FALSE to disable.
 */
static VOID
#ifdef CK_ANSIC
auth_encrypt_enable(BOOL enable)
#else