[3320] | 1 | /* vi: set sw=4 ts=4: */
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| 2 | /*
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| 3 | * telnet implementation for busybox
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| 4 | *
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| 5 | * Author: Tomi Ollila <too@iki.fi>
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| 6 | * Copyright (C) 1994-2000 by Tomi Ollila
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| 7 | *
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| 8 | * Created: Thu Apr 7 13:29:41 1994 too
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| 9 | * Last modified: Fri Jun 9 14:34:24 2000 too
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| 10 | *
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| 11 | * Licensed under GPLv2 or later, see file LICENSE in this source tree.
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| 12 | *
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| 13 | * HISTORY
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| 14 | * Revision 3.1 1994/04/17 11:31:54 too
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| 15 | * initial revision
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| 16 | * Modified 2000/06/13 for inclusion into BusyBox by Erik Andersen <andersen@codepoet.org>
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| 17 | * Modified 2001/05/07 to add ability to pass TTYPE to remote host by Jim McQuillan
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| 18 | * <jam@ltsp.org>
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| 19 | * Modified 2004/02/11 to add ability to pass the USER variable to remote host
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| 20 | * by Fernando Silveira <swrh@gmx.net>
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| 21 | *
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| 22 | */
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| 23 |
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| 24 | #include <arpa/telnet.h>
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| 25 | #include <netinet/in.h>
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| 26 | #include "libbb.h"
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| 27 |
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| 28 | #ifdef DOTRACE
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| 29 | #define TRACE(x, y) do { if (x) printf y; } while (0)
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| 30 | #else
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| 31 | #define TRACE(x, y)
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| 32 | #endif
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| 33 |
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| 34 | enum {
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| 35 | DATABUFSIZE = 128,
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| 36 | IACBUFSIZE = 128,
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| 37 |
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| 38 | CHM_TRY = 0,
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| 39 | CHM_ON = 1,
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| 40 | CHM_OFF = 2,
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| 41 |
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| 42 | UF_ECHO = 0x01,
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| 43 | UF_SGA = 0x02,
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| 44 |
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| 45 | TS_NORMAL = 0,
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| 46 | TS_COPY = 1,
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| 47 | TS_IAC = 2,
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| 48 | TS_OPT = 3,
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| 49 | TS_SUB1 = 4,
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| 50 | TS_SUB2 = 5,
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| 51 | TS_CR = 6,
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| 52 | };
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| 53 |
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| 54 | typedef unsigned char byte;
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| 55 |
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| 56 | enum { netfd = 3 };
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| 57 |
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| 58 | struct globals {
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| 59 | int iaclen; /* could even use byte, but it's a loss on x86 */
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| 60 | byte telstate; /* telnet negotiation state from network input */
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| 61 | byte telwish; /* DO, DONT, WILL, WONT */
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| 62 | byte charmode;
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| 63 | byte telflags;
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| 64 | byte do_termios;
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| 65 | #if ENABLE_FEATURE_TELNET_TTYPE
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| 66 | char *ttype;
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| 67 | #endif
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| 68 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
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| 69 | const char *autologin;
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| 70 | #endif
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| 71 | #if ENABLE_FEATURE_AUTOWIDTH
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| 72 | unsigned win_width, win_height;
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| 73 | #endif
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| 74 | /* same buffer used both for network and console read/write */
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| 75 | char buf[DATABUFSIZE];
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| 76 | /* buffer to handle telnet negotiations */
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| 77 | char iacbuf[IACBUFSIZE];
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| 78 | struct termios termios_def;
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| 79 | struct termios termios_raw;
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| 80 | } FIX_ALIASING;
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| 81 | #define G (*(struct globals*)&bb_common_bufsiz1)
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| 82 | #define INIT_G() do { \
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| 83 | struct G_sizecheck { \
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| 84 | char G_sizecheck[sizeof(G) > COMMON_BUFSIZE ? -1 : 1]; \
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| 85 | }; \
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| 86 | } while (0)
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| 87 |
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| 88 |
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| 89 | static void rawmode(void);
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| 90 | static void cookmode(void);
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| 91 | static void do_linemode(void);
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| 92 | static void will_charmode(void);
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| 93 | static void telopt(byte c);
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| 94 | static void subneg(byte c);
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| 95 |
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| 96 | static void iac_flush(void)
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| 97 | {
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| 98 | write(netfd, G.iacbuf, G.iaclen);
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| 99 | G.iaclen = 0;
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| 100 | }
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| 101 |
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| 102 | #define write_str(fd, str) write(fd, str, sizeof(str) - 1)
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| 103 |
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| 104 | static void doexit(int ev) NORETURN;
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| 105 | static void doexit(int ev)
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| 106 | {
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| 107 | cookmode();
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| 108 | exit(ev);
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| 109 | }
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| 110 |
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| 111 | static void con_escape(void)
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| 112 | {
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| 113 | char b;
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| 114 |
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| 115 | if (bb_got_signal) /* came from line mode... go raw */
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| 116 | rawmode();
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| 117 |
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| 118 | write_str(1, "\r\nConsole escape. Commands are:\r\n\n"
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| 119 | " l go to line mode\r\n"
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| 120 | " c go to character mode\r\n"
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| 121 | " z suspend telnet\r\n"
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| 122 | " e exit telnet\r\n");
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| 123 |
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| 124 | if (read(STDIN_FILENO, &b, 1) <= 0)
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| 125 | doexit(EXIT_FAILURE);
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| 126 |
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| 127 | switch (b) {
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| 128 | case 'l':
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| 129 | if (!bb_got_signal) {
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| 130 | do_linemode();
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| 131 | goto ret;
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| 132 | }
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| 133 | break;
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| 134 | case 'c':
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| 135 | if (bb_got_signal) {
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| 136 | will_charmode();
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| 137 | goto ret;
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| 138 | }
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| 139 | break;
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| 140 | case 'z':
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| 141 | cookmode();
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| 142 | kill(0, SIGTSTP);
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| 143 | rawmode();
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| 144 | break;
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| 145 | case 'e':
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| 146 | doexit(EXIT_SUCCESS);
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| 147 | }
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| 148 |
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| 149 | write_str(1, "continuing...\r\n");
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| 150 |
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| 151 | if (bb_got_signal)
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| 152 | cookmode();
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| 153 | ret:
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| 154 | bb_got_signal = 0;
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| 155 | }
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| 156 |
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| 157 | static void handle_net_output(int len)
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| 158 | {
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| 159 | /* here we could do smart tricks how to handle 0xFF:s in output
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| 160 | * stream like writing twice every sequence of FF:s (thus doing
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| 161 | * many write()s. But I think interactive telnet application does
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| 162 | * not need to be 100% 8-bit clean, so changing every 0xff:s to
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| 163 | * 0x7f:s
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| 164 | *
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| 165 | * 2002-mar-21, Przemyslaw Czerpak (druzus@polbox.com)
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| 166 | * I don't agree.
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| 167 | * first - I cannot use programs like sz/rz
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| 168 | * second - the 0x0D is sent as one character and if the next
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| 169 | * char is 0x0A then it's eaten by a server side.
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| 170 | * third - why do you have to make 'many write()s'?
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| 171 | * I don't understand.
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| 172 | * So I implemented it. It's really useful for me. I hope that
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| 173 | * other people will find it interesting too.
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| 174 | */
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| 175 | byte outbuf[2 * DATABUFSIZE];
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| 176 | byte *p = (byte*)G.buf;
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| 177 | int j = 0;
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| 178 |
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| 179 | for (; len > 0; len--, p++) {
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| 180 | byte c = *p;
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| 181 | if (c == 0x1d) {
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| 182 | con_escape();
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| 183 | return;
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| 184 | }
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| 185 | outbuf[j++] = c;
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| 186 | if (c == IAC)
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| 187 | outbuf[j++] = c; /* IAC -> IAC IAC */
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| 188 | else if (c == '\r')
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| 189 | outbuf[j++] = '\0'; /* CR -> CR NUL */
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| 190 | }
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| 191 | if (j > 0)
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| 192 | full_write(netfd, outbuf, j);
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| 193 | }
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| 194 |
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| 195 | static void handle_net_input(int len)
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| 196 | {
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| 197 | int i;
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| 198 | int cstart = 0;
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| 199 |
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| 200 | for (i = 0; i < len; i++) {
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| 201 | byte c = G.buf[i];
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| 202 |
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| 203 | if (G.telstate == TS_NORMAL) { /* most typical state */
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| 204 | if (c == IAC) {
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| 205 | cstart = i;
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| 206 | G.telstate = TS_IAC;
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| 207 | }
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| 208 | else if (c == '\r') {
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| 209 | cstart = i + 1;
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| 210 | G.telstate = TS_CR;
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| 211 | }
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| 212 | /* No IACs were seen so far, no need to copy
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| 213 | * bytes within G.buf: */
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| 214 | continue;
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| 215 | }
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| 216 |
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| 217 | switch (G.telstate) {
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| 218 | case TS_CR:
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| 219 | /* Prev char was CR. If cur one is NUL, ignore it.
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| 220 | * See RFC 1123 section 3.3.1 for discussion of telnet EOL handling.
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| 221 | */
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| 222 | G.telstate = TS_COPY;
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| 223 | if (c == '\0')
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| 224 | break;
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| 225 | /* else: fall through - need to handle CR IAC ... properly */
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| 226 |
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| 227 | case TS_COPY: /* Prev char was ordinary */
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| 228 | /* Similar to NORMAL, but in TS_COPY we need to copy bytes */
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| 229 | if (c == IAC)
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| 230 | G.telstate = TS_IAC;
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| 231 | else
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| 232 | G.buf[cstart++] = c;
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| 233 | if (c == '\r')
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| 234 | G.telstate = TS_CR;
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| 235 | break;
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| 236 |
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| 237 | case TS_IAC: /* Prev char was IAC */
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| 238 | if (c == IAC) { /* IAC IAC -> one IAC */
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| 239 | G.buf[cstart++] = c;
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| 240 | G.telstate = TS_COPY;
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| 241 | break;
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| 242 | }
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| 243 | /* else */
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| 244 | switch (c) {
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| 245 | case SB:
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| 246 | G.telstate = TS_SUB1;
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| 247 | break;
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| 248 | case DO:
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| 249 | case DONT:
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| 250 | case WILL:
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| 251 | case WONT:
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| 252 | G.telwish = c;
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| 253 | G.telstate = TS_OPT;
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| 254 | break;
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| 255 | /* DATA MARK must be added later */
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| 256 | default:
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| 257 | G.telstate = TS_COPY;
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| 258 | }
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| 259 | break;
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| 260 |
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| 261 | case TS_OPT: /* Prev chars were IAC WILL/WONT/DO/DONT */
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| 262 | telopt(c);
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| 263 | G.telstate = TS_COPY;
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| 264 | break;
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| 265 |
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| 266 | case TS_SUB1: /* Subnegotiation */
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| 267 | case TS_SUB2: /* Subnegotiation */
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| 268 | subneg(c); /* can change G.telstate */
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| 269 | break;
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| 270 | }
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| 271 | }
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| 272 |
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| 273 | if (G.telstate != TS_NORMAL) {
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| 274 | /* We had some IACs, or CR */
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| 275 | if (G.iaclen)
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| 276 | iac_flush();
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| 277 | if (G.telstate == TS_COPY) /* we aren't in the middle of IAC */
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| 278 | G.telstate = TS_NORMAL;
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| 279 | len = cstart;
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| 280 | }
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| 281 |
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| 282 | if (len)
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| 283 | full_write(STDOUT_FILENO, G.buf, len);
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| 284 | }
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| 285 |
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| 286 | static void put_iac(int c)
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| 287 | {
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| 288 | G.iacbuf[G.iaclen++] = c;
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| 289 | }
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| 290 |
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| 291 | static void put_iac2(byte wwdd, byte c)
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| 292 | {
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| 293 | if (G.iaclen + 3 > IACBUFSIZE)
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| 294 | iac_flush();
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| 295 |
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| 296 | put_iac(IAC);
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| 297 | put_iac(wwdd);
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| 298 | put_iac(c);
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| 299 | }
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| 300 |
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| 301 | #if ENABLE_FEATURE_TELNET_TTYPE
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| 302 | static void put_iac_subopt(byte c, char *str)
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| 303 | {
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| 304 | int len = strlen(str) + 6; // ( 2 + 1 + 1 + strlen + 2 )
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| 305 |
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| 306 | if (G.iaclen + len > IACBUFSIZE)
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| 307 | iac_flush();
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| 308 |
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| 309 | put_iac(IAC);
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| 310 | put_iac(SB);
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| 311 | put_iac(c);
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| 312 | put_iac(0);
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| 313 |
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| 314 | while (*str)
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| 315 | put_iac(*str++);
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| 316 |
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| 317 | put_iac(IAC);
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| 318 | put_iac(SE);
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| 319 | }
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| 320 | #endif
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| 321 |
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| 322 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
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| 323 | static void put_iac_subopt_autologin(void)
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| 324 | {
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| 325 | int len = strlen(G.autologin) + 6; // (2 + 1 + 1 + strlen + 2)
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| 326 | const char *p = "USER";
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| 327 |
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| 328 | if (G.iaclen + len > IACBUFSIZE)
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| 329 | iac_flush();
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| 330 |
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| 331 | put_iac(IAC);
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| 332 | put_iac(SB);
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| 333 | put_iac(TELOPT_NEW_ENVIRON);
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| 334 | put_iac(TELQUAL_IS);
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| 335 | put_iac(NEW_ENV_VAR);
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| 336 |
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| 337 | while (*p)
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| 338 | put_iac(*p++);
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| 339 |
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| 340 | put_iac(NEW_ENV_VALUE);
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| 341 |
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| 342 | p = G.autologin;
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| 343 | while (*p)
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| 344 | put_iac(*p++);
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| 345 |
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| 346 | put_iac(IAC);
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| 347 | put_iac(SE);
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| 348 | }
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| 349 | #endif
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| 350 |
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| 351 | #if ENABLE_FEATURE_AUTOWIDTH
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| 352 | static void put_iac_naws(byte c, int x, int y)
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| 353 | {
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| 354 | if (G.iaclen + 9 > IACBUFSIZE)
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| 355 | iac_flush();
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| 356 |
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| 357 | put_iac(IAC);
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| 358 | put_iac(SB);
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| 359 | put_iac(c);
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| 360 |
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| 361 | put_iac((x >> 8) & 0xff);
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| 362 | put_iac(x & 0xff);
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| 363 | put_iac((y >> 8) & 0xff);
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| 364 | put_iac(y & 0xff);
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| 365 |
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| 366 | put_iac(IAC);
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| 367 | put_iac(SE);
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| 368 | }
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| 369 | #endif
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| 370 |
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| 371 | static char const escapecharis[] ALIGN1 = "\r\nEscape character is ";
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| 372 |
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| 373 | static void setConMode(void)
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| 374 | {
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| 375 | if (G.telflags & UF_ECHO) {
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| 376 | if (G.charmode == CHM_TRY) {
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| 377 | G.charmode = CHM_ON;
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| 378 | printf("\r\nEntering character mode%s'^]'.\r\n", escapecharis);
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| 379 | rawmode();
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| 380 | }
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| 381 | } else {
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| 382 | if (G.charmode != CHM_OFF) {
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| 383 | G.charmode = CHM_OFF;
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| 384 | printf("\r\nEntering line mode%s'^C'.\r\n", escapecharis);
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| 385 | cookmode();
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| 386 | }
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| 387 | }
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| 388 | }
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| 389 |
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| 390 | static void will_charmode(void)
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| 391 | {
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| 392 | G.charmode = CHM_TRY;
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| 393 | G.telflags |= (UF_ECHO | UF_SGA);
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| 394 | setConMode();
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| 395 |
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| 396 | put_iac2(DO, TELOPT_ECHO);
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| 397 | put_iac2(DO, TELOPT_SGA);
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| 398 | iac_flush();
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| 399 | }
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| 400 |
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| 401 | static void do_linemode(void)
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| 402 | {
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| 403 | G.charmode = CHM_TRY;
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| 404 | G.telflags &= ~(UF_ECHO | UF_SGA);
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| 405 | setConMode();
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| 406 |
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| 407 | put_iac2(DONT, TELOPT_ECHO);
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| 408 | put_iac2(DONT, TELOPT_SGA);
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| 409 | iac_flush();
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| 410 | }
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| 411 |
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| 412 | static void to_notsup(char c)
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| 413 | {
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| 414 | if (G.telwish == WILL)
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| 415 | put_iac2(DONT, c);
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| 416 | else if (G.telwish == DO)
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| 417 | put_iac2(WONT, c);
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| 418 | }
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| 419 |
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| 420 | static void to_echo(void)
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| 421 | {
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| 422 | /* if server requests ECHO, don't agree */
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| 423 | if (G.telwish == DO) {
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| 424 | put_iac2(WONT, TELOPT_ECHO);
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| 425 | return;
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| 426 | }
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| 427 | if (G.telwish == DONT)
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| 428 | return;
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| 429 |
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| 430 | if (G.telflags & UF_ECHO) {
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| 431 | if (G.telwish == WILL)
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| 432 | return;
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| 433 | } else if (G.telwish == WONT)
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| 434 | return;
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| 435 |
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| 436 | if (G.charmode != CHM_OFF)
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| 437 | G.telflags ^= UF_ECHO;
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| 438 |
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| 439 | if (G.telflags & UF_ECHO)
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| 440 | put_iac2(DO, TELOPT_ECHO);
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| 441 | else
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| 442 | put_iac2(DONT, TELOPT_ECHO);
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| 443 |
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| 444 | setConMode();
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| 445 | full_write1_str("\r\n"); /* sudden modec */
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| 446 | }
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| 447 |
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| 448 | static void to_sga(void)
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| 449 | {
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| 450 | /* daemon always sends will/wont, client do/dont */
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| 451 |
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| 452 | if (G.telflags & UF_SGA) {
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| 453 | if (G.telwish == WILL)
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| 454 | return;
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| 455 | } else if (G.telwish == WONT)
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| 456 | return;
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| 457 |
|
---|
| 458 | G.telflags ^= UF_SGA; /* toggle */
|
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| 459 | if (G.telflags & UF_SGA)
|
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| 460 | put_iac2(DO, TELOPT_SGA);
|
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| 461 | else
|
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| 462 | put_iac2(DONT, TELOPT_SGA);
|
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| 463 | }
|
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| 464 |
|
---|
| 465 | #if ENABLE_FEATURE_TELNET_TTYPE
|
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| 466 | static void to_ttype(void)
|
---|
| 467 | {
|
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| 468 | /* Tell server we will (or won't) do TTYPE */
|
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| 469 | if (G.ttype)
|
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| 470 | put_iac2(WILL, TELOPT_TTYPE);
|
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| 471 | else
|
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| 472 | put_iac2(WONT, TELOPT_TTYPE);
|
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| 473 | }
|
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| 474 | #endif
|
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| 475 |
|
---|
| 476 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
|
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| 477 | static void to_new_environ(void)
|
---|
| 478 | {
|
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| 479 | /* Tell server we will (or will not) do AUTOLOGIN */
|
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| 480 | if (G.autologin)
|
---|
| 481 | put_iac2(WILL, TELOPT_NEW_ENVIRON);
|
---|
| 482 | else
|
---|
| 483 | put_iac2(WONT, TELOPT_NEW_ENVIRON);
|
---|
| 484 | }
|
---|
| 485 | #endif
|
---|
| 486 |
|
---|
| 487 | #if ENABLE_FEATURE_AUTOWIDTH
|
---|
| 488 | static void to_naws(void)
|
---|
| 489 | {
|
---|
| 490 | /* Tell server we will do NAWS */
|
---|
| 491 | put_iac2(WILL, TELOPT_NAWS);
|
---|
| 492 | }
|
---|
| 493 | #endif
|
---|
| 494 |
|
---|
| 495 | static void telopt(byte c)
|
---|
| 496 | {
|
---|
| 497 | switch (c) {
|
---|
| 498 | case TELOPT_ECHO:
|
---|
| 499 | to_echo(); break;
|
---|
| 500 | case TELOPT_SGA:
|
---|
| 501 | to_sga(); break;
|
---|
| 502 | #if ENABLE_FEATURE_TELNET_TTYPE
|
---|
| 503 | case TELOPT_TTYPE:
|
---|
| 504 | to_ttype(); break;
|
---|
| 505 | #endif
|
---|
| 506 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
|
---|
| 507 | case TELOPT_NEW_ENVIRON:
|
---|
| 508 | to_new_environ(); break;
|
---|
| 509 | #endif
|
---|
| 510 | #if ENABLE_FEATURE_AUTOWIDTH
|
---|
| 511 | case TELOPT_NAWS:
|
---|
| 512 | to_naws();
|
---|
| 513 | put_iac_naws(c, G.win_width, G.win_height);
|
---|
| 514 | break;
|
---|
| 515 | #endif
|
---|
| 516 | default:
|
---|
| 517 | to_notsup(c);
|
---|
| 518 | break;
|
---|
| 519 | }
|
---|
| 520 | }
|
---|
| 521 |
|
---|
| 522 | /* subnegotiation -- ignore all (except TTYPE,NAWS) */
|
---|
| 523 | static void subneg(byte c)
|
---|
| 524 | {
|
---|
| 525 | switch (G.telstate) {
|
---|
| 526 | case TS_SUB1:
|
---|
| 527 | if (c == IAC)
|
---|
| 528 | G.telstate = TS_SUB2;
|
---|
| 529 | #if ENABLE_FEATURE_TELNET_TTYPE
|
---|
| 530 | else
|
---|
| 531 | if (c == TELOPT_TTYPE && G.ttype)
|
---|
| 532 | put_iac_subopt(TELOPT_TTYPE, G.ttype);
|
---|
| 533 | #endif
|
---|
| 534 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
|
---|
| 535 | else
|
---|
| 536 | if (c == TELOPT_NEW_ENVIRON && G.autologin)
|
---|
| 537 | put_iac_subopt_autologin();
|
---|
| 538 | #endif
|
---|
| 539 | break;
|
---|
| 540 | case TS_SUB2:
|
---|
| 541 | if (c == SE) {
|
---|
| 542 | G.telstate = TS_COPY;
|
---|
| 543 | return;
|
---|
| 544 | }
|
---|
| 545 | G.telstate = TS_SUB1;
|
---|
| 546 | break;
|
---|
| 547 | }
|
---|
| 548 | }
|
---|
| 549 |
|
---|
| 550 | static void rawmode(void)
|
---|
| 551 | {
|
---|
| 552 | if (G.do_termios)
|
---|
| 553 | tcsetattr(0, TCSADRAIN, &G.termios_raw);
|
---|
| 554 | }
|
---|
| 555 |
|
---|
| 556 | static void cookmode(void)
|
---|
| 557 | {
|
---|
| 558 | if (G.do_termios)
|
---|
| 559 | tcsetattr(0, TCSADRAIN, &G.termios_def);
|
---|
| 560 | }
|
---|
| 561 |
|
---|
| 562 | int telnet_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
---|
| 563 | int telnet_main(int argc UNUSED_PARAM, char **argv)
|
---|
| 564 | {
|
---|
| 565 | char *host;
|
---|
| 566 | int port;
|
---|
| 567 | int len;
|
---|
| 568 | struct pollfd ufds[2];
|
---|
| 569 |
|
---|
| 570 | INIT_G();
|
---|
| 571 |
|
---|
| 572 | #if ENABLE_FEATURE_AUTOWIDTH
|
---|
| 573 | get_terminal_width_height(0, &G.win_width, &G.win_height);
|
---|
| 574 | #endif
|
---|
| 575 |
|
---|
| 576 | #if ENABLE_FEATURE_TELNET_TTYPE
|
---|
| 577 | G.ttype = getenv("TERM");
|
---|
| 578 | #endif
|
---|
| 579 |
|
---|
| 580 | if (tcgetattr(0, &G.termios_def) >= 0) {
|
---|
| 581 | G.do_termios = 1;
|
---|
| 582 | G.termios_raw = G.termios_def;
|
---|
| 583 | cfmakeraw(&G.termios_raw);
|
---|
| 584 | }
|
---|
| 585 |
|
---|
| 586 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
|
---|
| 587 | if (1 & getopt32(argv, "al:", &G.autologin))
|
---|
| 588 | G.autologin = getenv("USER");
|
---|
| 589 | argv += optind;
|
---|
| 590 | #else
|
---|
| 591 | argv++;
|
---|
| 592 | #endif
|
---|
| 593 | if (!*argv)
|
---|
| 594 | bb_show_usage();
|
---|
| 595 | host = *argv++;
|
---|
| 596 | port = bb_lookup_port(*argv ? *argv++ : "telnet", "tcp", 23);
|
---|
| 597 | if (*argv) /* extra params?? */
|
---|
| 598 | bb_show_usage();
|
---|
| 599 |
|
---|
| 600 | xmove_fd(create_and_connect_stream_or_die(host, port), netfd);
|
---|
| 601 |
|
---|
| 602 | setsockopt(netfd, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
|
---|
| 603 |
|
---|
| 604 | signal(SIGINT, record_signo);
|
---|
| 605 |
|
---|
| 606 | ufds[0].fd = STDIN_FILENO;
|
---|
| 607 | ufds[0].events = POLLIN;
|
---|
| 608 | ufds[1].fd = netfd;
|
---|
| 609 | ufds[1].events = POLLIN;
|
---|
| 610 |
|
---|
| 611 | while (1) {
|
---|
| 612 | if (poll(ufds, 2, -1) < 0) {
|
---|
| 613 | /* error, ignore and/or log something, bay go to loop */
|
---|
| 614 | if (bb_got_signal)
|
---|
| 615 | con_escape();
|
---|
| 616 | else
|
---|
| 617 | sleep(1);
|
---|
| 618 | continue;
|
---|
| 619 | }
|
---|
| 620 |
|
---|
| 621 | // FIXME: reads can block. Need full bidirectional buffering.
|
---|
| 622 |
|
---|
| 623 | if (ufds[0].revents) {
|
---|
| 624 | len = safe_read(STDIN_FILENO, G.buf, DATABUFSIZE);
|
---|
| 625 | if (len <= 0)
|
---|
| 626 | doexit(EXIT_SUCCESS);
|
---|
| 627 | TRACE(0, ("Read con: %d\n", len));
|
---|
| 628 | handle_net_output(len);
|
---|
| 629 | }
|
---|
| 630 |
|
---|
| 631 | if (ufds[1].revents) {
|
---|
| 632 | len = safe_read(netfd, G.buf, DATABUFSIZE);
|
---|
| 633 | if (len <= 0) {
|
---|
| 634 | full_write1_str("Connection closed by foreign host\r\n");
|
---|
| 635 | doexit(EXIT_FAILURE);
|
---|
| 636 | }
|
---|
| 637 | TRACE(0, ("Read netfd (%d): %d\n", netfd, len));
|
---|
| 638 | handle_net_input(len);
|
---|
| 639 | }
|
---|
| 640 | } /* while (1) */
|
---|
| 641 | }
|
---|