NetBSD/lib/libtelnet/encrypt.c

961 lines
22 KiB
C

/* $NetBSD: encrypt.c,v 1.18 2019/01/05 08:55:58 maya Exp $ */
/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#if 0
static char sccsid[] = "@(#)encrypt.c 8.2 (Berkeley) 5/30/95";
#else
__RCSID("$NetBSD: encrypt.c,v 1.18 2019/01/05 08:55:58 maya Exp $");
#endif /* not lint */
/*
* Copyright (C) 1990 by the Massachusetts Institute of Technology
*
* Export of this software from the United States of America is assumed
* to require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*/
#ifdef ENCRYPTION
#include <stdio.h>
#define ENCRYPT_NAMES
#include <arpa/telnet.h>
#include "encrypt.h"
#include "misc.h"
#include <stdlib.h>
#ifdef NO_STRING_H
#include <strings.h>
#else
#include <string.h>
#endif
/*
* These functions pointers point to the current routines
* for encrypting and decrypting data.
*/
void (*encrypt_output)(unsigned char *, int);
int (*decrypt_input)(int);
int encrypt_debug_mode = 0;
static int decrypt_mode = 0;
static int encrypt_mode = 0;
static int encrypt_verbose = 0;
static int autoencrypt = 0;
static int autodecrypt = 0;
static int havesessionkey = 0;
static int Server = 0;
static const char *Name = "Noname";
#define typemask(x) ((x) > 0 ? 1 << ((x)-1) : 0)
static long i_support_encrypt = typemask(ENCTYPE_DES_CFB64)
| typemask(ENCTYPE_DES_OFB64);
static long i_support_decrypt = typemask(ENCTYPE_DES_CFB64)
| typemask(ENCTYPE_DES_OFB64);
static long i_wont_support_encrypt = 0;
static long i_wont_support_decrypt = 0;
#define I_SUPPORT_ENCRYPT (i_support_encrypt & ~i_wont_support_encrypt)
#define I_SUPPORT_DECRYPT (i_support_decrypt & ~i_wont_support_decrypt)
static long remote_supports_encrypt = 0;
static long remote_supports_decrypt = 0;
static Encryptions encryptions[] = {
#ifdef DES_ENCRYPTION
{ "DES_CFB64", ENCTYPE_DES_CFB64,
cfb64_encrypt,
cfb64_decrypt,
cfb64_init,
cfb64_start,
cfb64_is,
cfb64_reply,
cfb64_session,
cfb64_keyid,
cfb64_printsub },
{ "DES_OFB64", ENCTYPE_DES_OFB64,
ofb64_encrypt,
ofb64_decrypt,
ofb64_init,
ofb64_start,
ofb64_is,
ofb64_reply,
ofb64_session,
ofb64_keyid,
ofb64_printsub },
#endif /* DES_ENCRYPTION */
{ .name = 0 },
};
static unsigned char str_send[64] = { IAC, SB, TELOPT_ENCRYPT,
ENCRYPT_SUPPORT };
static unsigned char str_suplen = 0;
static unsigned char str_start[72] = { IAC, SB, TELOPT_ENCRYPT };
static unsigned char str_end[] = { IAC, SB, TELOPT_ENCRYPT, 0, IAC, SE };
Encryptions *
findencryption(int type)
{
Encryptions *ep = encryptions;
if (!(I_SUPPORT_ENCRYPT & remote_supports_decrypt & typemask(type)))
return(0);
while (ep->type && ep->type != type)
++ep;
return(ep->type ? ep : 0);
}
Encryptions *
finddecryption(int type)
{
Encryptions *ep = encryptions;
if (!(I_SUPPORT_DECRYPT & remote_supports_encrypt & typemask(type)))
return(0);
while (ep->type && ep->type != type)
++ep;
return(ep->type ? ep : 0);
}
#define MAXKEYLEN 64
static struct key_info {
unsigned char keyid[MAXKEYLEN];
int keylen;
int dir;
int *modep;
Encryptions *(*getcrypt)(int);
} ki[2] = {
{ { 0 }, 0, DIR_ENCRYPT, &encrypt_mode, findencryption },
{ { 0 }, 0, DIR_DECRYPT, &decrypt_mode, finddecryption },
};
void
encrypt_init(const char *name, int server)
{
Encryptions *ep = encryptions;
Name = name;
Server = server;
i_support_encrypt = i_support_decrypt = 0;
remote_supports_encrypt = remote_supports_decrypt = 0;
encrypt_mode = 0;
decrypt_mode = 0;
encrypt_output = 0;
decrypt_input = 0;
#ifdef notdef
encrypt_verbose = !server;
#endif
str_suplen = 4;
while (ep->type) {
if (encrypt_debug_mode)
printf(">>>%s: I will support %s\r\n",
Name, ENCTYPE_NAME(ep->type));
i_support_encrypt |= typemask(ep->type);
i_support_decrypt |= typemask(ep->type);
if ((i_wont_support_decrypt & typemask(ep->type)) == 0)
if ((str_send[str_suplen++] = ep->type) == IAC)
str_send[str_suplen++] = IAC;
if (ep->init)
(*ep->init)(Server);
++ep;
}
str_send[str_suplen++] = IAC;
str_send[str_suplen++] = SE;
}
void
encrypt_list_types(void)
{
Encryptions *ep = encryptions;
printf("Valid encryption types:\n");
while (ep->type) {
printf("\t%s (%d)\r\n", ENCTYPE_NAME(ep->type), ep->type);
++ep;
}
}
int
EncryptEnable(char *type, char *mode)
{
if (isprefix(type, "help") || isprefix(type, "?")) {
printf("Usage: encrypt enable <type> [input|output]\n");
encrypt_list_types();
return 0;
}
if (EncryptType(type, mode))
return EncryptStart(mode, NULL);
return 0;
}
int
EncryptDisable(char *type, char *mode)
{
register Encryptions *ep;
int ret = 0;
if (isprefix(type, "help") || isprefix(type, "?")) {
printf("Usage: encrypt disable <type> [input|output]\n");
encrypt_list_types();
} else if ((ep = (Encryptions *)genget(type, (char **)encryptions,
sizeof(Encryptions))) == 0) {
printf("%s: invalid encryption type\n", type);
} else if (Ambiguous(ep)) {
printf("Ambiguous type '%s'\n", type);
} else {
if ((mode == 0) || (isprefix(mode, "input") ? 1 : 0)) {
if (decrypt_mode == ep->type)
EncryptStopInput(NULL, NULL);
i_wont_support_decrypt |= typemask(ep->type);
ret = 1;
}
if ((mode == 0) || (isprefix(mode, "output"))) {
if (encrypt_mode == ep->type)
EncryptStopOutput(NULL, NULL);
i_wont_support_encrypt |= typemask(ep->type);
ret = 1;
}
if (ret == 0)
printf("%s: invalid encryption mode\n", mode);
}
return(ret);
}
int
EncryptType(char *type, char *mode)
{
register Encryptions *ep;
int ret = 0;
if (isprefix(type, "help") || isprefix(type, "?")) {
printf("Usage: encrypt type <type> [input|output]\n");
encrypt_list_types();
} else if ((ep = (Encryptions *)genget(type, (char **)encryptions,
sizeof(Encryptions))) == 0) {
printf("%s: invalid encryption type\n", type);
} else if (Ambiguous(ep)) {
printf("Ambiguous type '%s'\n", type);
} else {
if ((mode == 0) || isprefix(mode, "input")) {
decrypt_mode = ep->type;
i_wont_support_decrypt &= ~typemask(ep->type);
ret = 1;
}
if ((mode == 0) || isprefix(mode, "output")) {
encrypt_mode = ep->type;
i_wont_support_encrypt &= ~typemask(ep->type);
ret = 1;
}
if (ret == 0)
printf("%s: invalid encryption mode\n", mode);
}
return(ret);
}
int
EncryptStart(char *mode, char *unused __unused)
{
register int ret = 0;
if (mode) {
if (isprefix(mode, "input"))
return EncryptStartInput(NULL, NULL);
if (isprefix(mode, "output"))
return EncryptStartOutput(NULL, NULL);
if (isprefix(mode, "help") || isprefix(mode, "?")) {
printf("Usage: encrypt start [input|output]\n");
return 0;
}
printf("%s: invalid encryption mode 'encrypt start ?' for help\n", mode);
return 0;
}
ret += EncryptStartInput(NULL, NULL);
ret += EncryptStartOutput(NULL, NULL);
return ret;
}
int
EncryptStartInput(char *unused1 __unused, char *unused2 __unused)
{
if (decrypt_mode) {
encrypt_send_request_start();
return(1);
}
printf("No previous decryption mode, decryption not enabled\r\n");
return(0);
}
int
EncryptStartOutput(char *unused1 __unused, char *unused2 __unused)
{
if (encrypt_mode) {
encrypt_start_output(encrypt_mode);
return(1);
}
printf("No previous encryption mode, encryption not enabled\r\n");
return(0);
}
int
EncryptStop(char *mode, char *unused __unused)
{
int ret = 0;
if (mode) {
if (isprefix(mode, "input"))
return EncryptStopInput(NULL, NULL);
if (isprefix(mode, "output"))
return EncryptStopOutput(NULL, NULL);
if (isprefix(mode, "help") || isprefix(mode, "?")) {
printf("Usage: encrypt stop [input|output]\n");
return 0;
}
printf("%s: invalid encryption mode 'encrypt stop ?' for help\n", mode);
return 0;
}
ret += EncryptStopInput(NULL, NULL);
ret += EncryptStopOutput(NULL, NULL);
return ret;
}
int
EncryptStopInput(char *unused1 __unused, char *unused2 __unused)
{
encrypt_send_request_end();
return 1;
}
int
EncryptStopOutput(char *unused1 __unused, char *unused2 __unused)
{
encrypt_send_end();
return 1;
}
void
encrypt_display(void)
{
if (encrypt_output)
printf("Currently encrypting output with %s\r\n",
ENCTYPE_NAME(encrypt_mode));
if (decrypt_input)
printf("Currently decrypting input with %s\r\n",
ENCTYPE_NAME(decrypt_mode));
}
int
EncryptStatus(char *unused1 __unused, char *unused2 __unused)
{
if (encrypt_output)
printf("Currently encrypting output with %s\r\n",
ENCTYPE_NAME(encrypt_mode));
else if (encrypt_mode) {
printf("Currently output is clear text.\r\n");
printf("Last encryption mode was %s\r\n",
ENCTYPE_NAME(encrypt_mode));
}
if (decrypt_input) {
printf("Currently decrypting input with %s\r\n",
ENCTYPE_NAME(decrypt_mode));
} else if (decrypt_mode) {
printf("Currently input is clear text.\r\n");
printf("Last decryption mode was %s\r\n",
ENCTYPE_NAME(decrypt_mode));
}
return 1;
}
void
encrypt_send_support(void)
{
if (str_suplen) {
/*
* If the user has requested that decryption start
* immediatly, then send a "REQUEST START" before
* we negotiate the type.
*/
if (!Server && autodecrypt)
encrypt_send_request_start();
telnet_net_write(str_send, str_suplen);
printsub('>', &str_send[2], str_suplen - 2);
str_suplen = 0;
}
}
int
EncryptDebug(int on)
{
if (on < 0)
encrypt_debug_mode ^= 1;
else
encrypt_debug_mode = on;
printf("Encryption debugging %s\r\n",
encrypt_debug_mode ? "enabled" : "disabled");
return(1);
}
int
EncryptVerbose(int on)
{
if (on < 0)
encrypt_verbose ^= 1;
else
encrypt_verbose = on;
printf("Encryption %s verbose\r\n",
encrypt_verbose ? "is" : "is not");
return(1);
}
int
EncryptAutoEnc(int on)
{
encrypt_auto(on);
printf("Automatic encryption of output is %s\r\n",
autoencrypt ? "enabled" : "disabled");
return(1);
}
int
EncryptAutoDec(int on)
{
decrypt_auto(on);
printf("Automatic decryption of input is %s\r\n",
autodecrypt ? "enabled" : "disabled");
return(1);
}
/*
* Called when ENCRYPT SUPPORT is received.
*/
void
encrypt_support(unsigned char *typelist, int cnt)
{
register int type, use_type = 0;
Encryptions *ep;
/*
* Forget anything the other side has previously told us.
*/
remote_supports_decrypt = 0;
while (cnt-- > 0) {
type = *typelist++;
if (encrypt_debug_mode)
printf(">>>%s: He is supporting %s (%d)\r\n",
Name,
ENCTYPE_NAME(type), type);
if ((type < ENCTYPE_CNT) &&
(I_SUPPORT_ENCRYPT & typemask(type))) {
remote_supports_decrypt |= typemask(type);
if (use_type == 0)
use_type = type;
}
}
if (use_type) {
ep = findencryption(use_type);
if (!ep)
return;
type = ep->start ? (*ep->start)(DIR_ENCRYPT, Server) : 0;
if (encrypt_debug_mode)
printf(">>>%s: (*ep->start)() returned %d\r\n",
Name, type);
if (type < 0)
return;
encrypt_mode = use_type;
if (type == 0)
encrypt_start_output(use_type);
}
}
void
encrypt_is(unsigned char *data, int cnt)
{
Encryptions *ep;
register int type, ret;
if (--cnt < 0)
return;
type = *data++;
if (type < ENCTYPE_CNT)
remote_supports_encrypt |= typemask(type);
if (!(ep = finddecryption(type))) {
if (encrypt_debug_mode)
printf(">>>%s: Can't find type %s (%d) for initial negotiation\r\n",
Name,
ENCTYPE_NAME_OK(type)
? ENCTYPE_NAME(type) : "(unknown)",
type);
return;
}
if (!ep->is) {
if (encrypt_debug_mode)
printf(">>>%s: No initial negotiation needed for type %s (%d)\r\n",
Name,
ENCTYPE_NAME_OK(type)
? ENCTYPE_NAME(type) : "(unknown)",
type);
ret = 0;
} else {
ret = (*ep->is)(data, cnt);
if (encrypt_debug_mode)
printf("(*ep->is)(%p, %d) returned %s(%d)\n", data, cnt,
(ret < 0) ? "FAIL " :
(ret == 0) ? "SUCCESS " : "MORE_TO_DO ", ret);
}
if (ret < 0) {
autodecrypt = 0;
} else {
decrypt_mode = type;
if (ret == 0 && autodecrypt)
encrypt_send_request_start();
}
}
void
encrypt_reply(unsigned char *data, int cnt)
{
Encryptions *ep;
register int ret, type;
if (--cnt < 0)
return;
type = *data++;
if (!(ep = findencryption(type))) {
if (encrypt_debug_mode)
printf(">>>%s: Can't find type %s (%d) for initial negotiation\r\n",
Name,
ENCTYPE_NAME_OK(type)
? ENCTYPE_NAME(type) : "(unknown)",
type);
return;
}
if (!ep->reply) {
if (encrypt_debug_mode)
printf(">>>%s: No initial negotiation needed for type %s (%d)\r\n",
Name,
ENCTYPE_NAME_OK(type)
? ENCTYPE_NAME(type) : "(unknown)",
type);
ret = 0;
} else {
ret = (*ep->reply)(data, cnt);
if (encrypt_debug_mode)
printf("(*ep->reply)(%p, %d) returned %s(%d)\n",
data, cnt,
(ret < 0) ? "FAIL " :
(ret == 0) ? "SUCCESS " : "MORE_TO_DO ", ret);
}
if (encrypt_debug_mode)
printf(">>>%s: encrypt_reply returned %d\n", Name, ret);
if (ret < 0) {
autoencrypt = 0;
} else {
encrypt_mode = type;
if (ret == 0 && autoencrypt)
encrypt_start_output(type);
}
}
/*
* Called when a ENCRYPT START command is received.
*/
void
encrypt_start(unsigned char *data, int cnt)
{
Encryptions *ep;
if (!decrypt_mode) {
/*
* Something is wrong. We should not get a START
* command without having already picked our
* decryption scheme. Send a REQUEST-END to
* attempt to clear the channel...
*/
printf("%s: Warning, Cannot decrypt input stream!!!\r\n", Name);
encrypt_send_request_end();
return;
}
if ((ep = finddecryption(decrypt_mode)) != NULL) {
decrypt_input = ep->input;
if (encrypt_verbose)
printf("[ Input is now decrypted with type %s ]\r\n",
ENCTYPE_NAME(decrypt_mode));
if (encrypt_debug_mode)
printf(">>>%s: Start to decrypt input with type %s\r\n",
Name, ENCTYPE_NAME(decrypt_mode));
} else {
printf("%s: Warning, Cannot decrypt type %s (%d)!!!\r\n",
Name,
ENCTYPE_NAME_OK(decrypt_mode)
? ENCTYPE_NAME(decrypt_mode)
: "(unknown)",
decrypt_mode);
encrypt_send_request_end();
}
}
void
encrypt_session_key(Session_Key *key, int server)
{
Encryptions *ep = encryptions;
havesessionkey = 1;
while (ep->type) {
if (ep->session)
(*ep->session)(key, server);
#ifdef notdef
if (!encrypt_output && autoencrypt && !server)
encrypt_start_output(ep->type);
if (!decrypt_input && autodecrypt && !server)
encrypt_send_request_start();
#endif
++ep;
}
}
/*
* Called when ENCRYPT END is received.
*/
void
encrypt_end(void)
{
decrypt_input = 0;
if (encrypt_debug_mode)
printf(">>>%s: Input is back to clear text\r\n", Name);
if (encrypt_verbose)
printf("[ Input is now clear text ]\r\n");
}
/*
* Called when ENCRYPT REQUEST-END is received.
*/
void
encrypt_request_end(void)
{
encrypt_send_end();
}
/*
* Called when ENCRYPT REQUEST-START is received. If we receive
* this before a type is picked, then that indicates that the
* other side wants us to start encrypting data as soon as we
* can.
*/
void
encrypt_request_start(unsigned char *data, int cnt)
{
if (encrypt_mode == 0) {
if (Server)
autoencrypt = 1;
return;
}
encrypt_start_output(encrypt_mode);
}
static unsigned char str_keyid[(MAXKEYLEN*2)+5] = { IAC, SB, TELOPT_ENCRYPT };
void
encrypt_enc_keyid(unsigned char *keyid, int len)
{
encrypt_keyid(&ki[1], keyid, len);
}
void
encrypt_dec_keyid(unsigned char *keyid, int len)
{
encrypt_keyid(&ki[0], keyid, len);
}
void
encrypt_keyid(struct key_info *kp, unsigned char *keyid, int len)
{
Encryptions *ep;
int dir = kp->dir;
register int ret = 0;
if (!(ep = (*kp->getcrypt)(*kp->modep))) {
if (len == 0)
return;
kp->keylen = 0;
} else if (len == 0) {
/*
* Empty option, indicates a failure.
*/
if (kp->keylen == 0)
return;
kp->keylen = 0;
if (ep->keyid)
(void)(*ep->keyid)(dir, kp->keyid, &kp->keylen);
} else if ((size_t)len > sizeof(kp->keyid)) {
return;
} else if ((len != kp->keylen) ||
(memcmp(keyid, kp->keyid, len) != 0)) {
/*
* Length or contents are different
*/
kp->keylen = len;
memmove(kp->keyid, keyid, len);
if (ep->keyid)
(void)(*ep->keyid)(dir, kp->keyid, &kp->keylen);
} else {
if (ep->keyid)
ret = (*ep->keyid)(dir, kp->keyid, &kp->keylen);
if ((ret == 0) && (dir == DIR_ENCRYPT) && autoencrypt)
encrypt_start_output(*kp->modep);
return;
}
encrypt_send_keyid(dir, kp->keyid, kp->keylen, 0);
}
void
encrypt_send_keyid(int dir, const unsigned char *keyid, int keylen, int saveit)
{
unsigned char *strp;
str_keyid[3] = (dir == DIR_ENCRYPT)
? ENCRYPT_ENC_KEYID : ENCRYPT_DEC_KEYID;
if (saveit) {
struct key_info *kp = &ki[(dir == DIR_ENCRYPT) ? 0 : 1];
memmove(kp->keyid, keyid, keylen);
kp->keylen = keylen;
}
for (strp = &str_keyid[4]; keylen > 0; --keylen) {
if ((*strp++ = *keyid++) == IAC)
*strp++ = IAC;
}
*strp++ = IAC;
*strp++ = SE;
telnet_net_write(str_keyid, strp - str_keyid);
printsub('>', &str_keyid[2], strp - str_keyid - 2);
}
void
encrypt_auto(int on)
{
if (on < 0)
autoencrypt ^= 1;
else
autoencrypt = on ? 1 : 0;
}
void
decrypt_auto(int on)
{
if (on < 0)
autodecrypt ^= 1;
else
autodecrypt = on ? 1 : 0;
}
void
encrypt_start_output(int type)
{
Encryptions *ep;
register unsigned char *p;
register int i;
if (!(ep = findencryption(type))) {
if (encrypt_debug_mode) {
printf(">>>%s: Can't encrypt with type %s (%d)\r\n",
Name,
ENCTYPE_NAME_OK(type)
? ENCTYPE_NAME(type) : "(unknown)",
type);
}
return;
}
if (ep->start) {
i = (*ep->start)(DIR_ENCRYPT, Server);
if (encrypt_debug_mode) {
printf(">>>%s: Encrypt start: %s (%d) %s\r\n",
Name,
(i < 0) ? "failed" :
"initial negotiation in progress",
i, ENCTYPE_NAME(type));
}
if (i)
return;
}
p = str_start + 3;
*p++ = ENCRYPT_START;
for (i = 0; i < ki[0].keylen; ++i) {
if ((*p++ = ki[0].keyid[i]) == IAC)
*p++ = IAC;
}
*p++ = IAC;
*p++ = SE;
telnet_net_write(str_start, p - str_start);
net_encrypt();
printsub('>', &str_start[2], p - &str_start[2]);
/*
* If we are already encrypting in some mode, then
* encrypt the ring (which includes our request) in
* the old mode, mark it all as "clear text" and then
* switch to the new mode.
*/
encrypt_output = ep->output;
encrypt_mode = type;
if (encrypt_debug_mode)
printf(">>>%s: Started to encrypt output with type %s\r\n",
Name, ENCTYPE_NAME(type));
if (encrypt_verbose)
printf("[ Output is now encrypted with type %s ]\r\n",
ENCTYPE_NAME(type));
}
void
encrypt_send_end(void)
{
if (!encrypt_output)
return;
str_end[3] = ENCRYPT_END;
telnet_net_write(str_end, sizeof(str_end));
net_encrypt();
printsub('>', &str_end[2], sizeof(str_end) - 2);
/*
* Encrypt the output buffer now because it will not be done by
* netflush...
*/
encrypt_output = 0;
if (encrypt_debug_mode)
printf(">>>%s: Output is back to clear text\r\n", Name);
if (encrypt_verbose)
printf("[ Output is now clear text ]\r\n");
}
void
encrypt_send_request_start(void)
{
register unsigned char *p;
register int i;
p = &str_start[3];
*p++ = ENCRYPT_REQSTART;
for (i = 0; i < ki[1].keylen; ++i) {
if ((*p++ = ki[1].keyid[i]) == IAC)
*p++ = IAC;
}
*p++ = IAC;
*p++ = SE;
telnet_net_write(str_start, p - str_start);
printsub('>', &str_start[2], p - &str_start[2]);
if (encrypt_debug_mode)
printf(">>>%s: Request input to be encrypted\r\n", Name);
}
void
encrypt_send_request_end(void)
{
str_end[3] = ENCRYPT_REQEND;
telnet_net_write(str_end, sizeof(str_end));
printsub('>', &str_end[2], sizeof(str_end) - 2);
if (encrypt_debug_mode)
printf(">>>%s: Request input to be clear text\r\n", Name);
}
void
encrypt_wait(void)
{
if (encrypt_debug_mode)
printf(">>>%s: in encrypt_wait\r\n", Name);
if (!havesessionkey || !(I_SUPPORT_ENCRYPT & remote_supports_decrypt))
return;
while (autoencrypt && !encrypt_output)
if (telnet_spin())
return;
}
void
encrypt_debug(int mode)
{
encrypt_debug_mode = mode;
}
void
encrypt_gen_printsub(unsigned char *data, int cnt,
unsigned char *buf, int buflen)
{
char tbuf[16], *cp;
cnt -= 2;
data += 2;
buf[buflen-1] = '\0';
buf[buflen-2] = '*';
buflen -= 2;
for (; cnt > 0; cnt--, data++) {
snprintf(tbuf, sizeof(tbuf), " %d", *data);
for (cp = tbuf; *cp && buflen > 0; --buflen)
*buf++ = *cp++;
if (buflen <= 0)
return;
}
*buf = '\0';
}
void
encrypt_printsub(unsigned char *data, int cnt,
unsigned char *buf, int buflen)
{
Encryptions *ep;
register int type = data[1];
for (ep = encryptions; ep->type && ep->type != type; ep++)
;
if (ep->printsub)
(*ep->printsub)(data, cnt, buf, buflen);
else
encrypt_gen_printsub(data, cnt, buf, buflen);
}
#endif /* ENCRYPTION */