[821] | 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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[2725] | 11 | * Licensed under GPLv2 or later, see file LICENSE in this source tree.
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[821] | 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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[3232] | 24 | //usage:#if ENABLE_FEATURE_TELNET_AUTOLOGIN
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| 25 | //usage:#define telnet_trivial_usage
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| 26 | //usage: "[-a] [-l USER] HOST [PORT]"
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| 27 | //usage:#define telnet_full_usage "\n\n"
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| 28 | //usage: "Connect to telnet server\n"
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| 29 | //usage: "\n -a Automatic login with $USER variable"
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| 30 | //usage: "\n -l USER Automatic login as USER"
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| 31 | //usage:
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| 32 | //usage:#else
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| 33 | //usage:#define telnet_trivial_usage
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| 34 | //usage: "HOST [PORT]"
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| 35 | //usage:#define telnet_full_usage "\n\n"
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| 36 | //usage: "Connect to telnet server"
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| 37 | //usage:#endif
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| 38 |
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[821] | 39 | #include <arpa/telnet.h>
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| 40 | #include <netinet/in.h>
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[1765] | 41 | #include "libbb.h"
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[3621] | 42 | #include "common_bufsiz.h"
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[821] | 43 |
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[3232] | 44 | #ifdef __BIONIC__
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| 45 | /* should be in arpa/telnet.h */
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| 46 | # define IAC 255 /* interpret as command: */
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| 47 | # define DONT 254 /* you are not to use option */
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| 48 | # define DO 253 /* please, you use option */
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| 49 | # define WONT 252 /* I won't use option */
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| 50 | # define WILL 251 /* I will use option */
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| 51 | # define SB 250 /* interpret as subnegotiation */
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| 52 | # define SE 240 /* end sub negotiation */
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| 53 | # define TELOPT_ECHO 1 /* echo */
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| 54 | # define TELOPT_SGA 3 /* suppress go ahead */
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| 55 | # define TELOPT_TTYPE 24 /* terminal type */
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| 56 | # define TELOPT_NAWS 31 /* window size */
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| 57 | #endif
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| 58 |
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[821] | 59 | #ifdef DOTRACE
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[3232] | 60 | # define TRACE(x, y) do { if (x) printf y; } while (0)
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[821] | 61 | #else
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[3232] | 62 | # define TRACE(x, y)
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[821] | 63 | #endif
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| 64 |
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[1765] | 65 | enum {
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| 66 | DATABUFSIZE = 128,
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| 67 | IACBUFSIZE = 128,
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[821] | 68 |
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| 69 | CHM_TRY = 0,
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| 70 | CHM_ON = 1,
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| 71 | CHM_OFF = 2,
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| 72 |
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| 73 | UF_ECHO = 0x01,
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| 74 | UF_SGA = 0x02,
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| 75 |
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[2725] | 76 | TS_NORMAL = 0,
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| 77 | TS_COPY = 1,
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[821] | 78 | TS_IAC = 2,
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| 79 | TS_OPT = 3,
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| 80 | TS_SUB1 = 4,
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| 81 | TS_SUB2 = 5,
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[2725] | 82 | TS_CR = 6,
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[821] | 83 | };
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| 84 |
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| 85 | typedef unsigned char byte;
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| 86 |
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[2725] | 87 | enum { netfd = 3 };
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| 88 |
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[1765] | 89 | struct globals {
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[2725] | 90 | int iaclen; /* could even use byte, but it's a loss on x86 */
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[821] | 91 | byte telstate; /* telnet negotiation state from network input */
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| 92 | byte telwish; /* DO, DONT, WILL, WONT */
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| 93 | byte charmode;
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| 94 | byte telflags;
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| 95 | byte do_termios;
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[1765] | 96 | #if ENABLE_FEATURE_TELNET_TTYPE
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| 97 | char *ttype;
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| 98 | #endif
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| 99 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
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| 100 | const char *autologin;
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| 101 | #endif
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| 102 | #if ENABLE_FEATURE_AUTOWIDTH
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[2725] | 103 | unsigned win_width, win_height;
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[1765] | 104 | #endif
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| 105 | /* same buffer used both for network and console read/write */
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| 106 | char buf[DATABUFSIZE];
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[821] | 107 | /* buffer to handle telnet negotiations */
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| 108 | char iacbuf[IACBUFSIZE];
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| 109 | struct termios termios_def;
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| 110 | struct termios termios_raw;
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[2725] | 111 | } FIX_ALIASING;
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[3621] | 112 | #define G (*(struct globals*)bb_common_bufsiz1)
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[1765] | 113 | #define INIT_G() do { \
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[3621] | 114 | setup_common_bufsiz(); \
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| 115 | BUILD_BUG_ON(sizeof(G) > COMMON_BUFSIZE); \
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[1765] | 116 | } while (0)
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[821] | 117 |
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[2725] | 118 |
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[821] | 119 | static void rawmode(void);
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| 120 | static void cookmode(void);
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| 121 | static void do_linemode(void);
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| 122 | static void will_charmode(void);
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| 123 | static void telopt(byte c);
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[2725] | 124 | static void subneg(byte c);
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[821] | 125 |
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[2725] | 126 | static void iac_flush(void)
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[1765] | 127 | {
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[3621] | 128 | full_write(netfd, G.iacbuf, G.iaclen);
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[1765] | 129 | G.iaclen = 0;
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| 130 | }
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[821] | 131 |
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[2725] | 132 | static void doexit(int ev) NORETURN;
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[821] | 133 | static void doexit(int ev)
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| 134 | {
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| 135 | cookmode();
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| 136 | exit(ev);
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| 137 | }
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| 138 |
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[2725] | 139 | static void con_escape(void)
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[821] | 140 | {
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| 141 | char b;
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| 142 |
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[2725] | 143 | if (bb_got_signal) /* came from line mode... go raw */
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[821] | 144 | rawmode();
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| 145 |
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[3621] | 146 | full_write1_str("\r\nConsole escape. Commands are:\r\n\n"
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[821] | 147 | " l go to line mode\r\n"
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| 148 | " c go to character mode\r\n"
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| 149 | " z suspend telnet\r\n"
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| 150 | " e exit telnet\r\n");
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| 151 |
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[2725] | 152 | if (read(STDIN_FILENO, &b, 1) <= 0)
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| 153 | doexit(EXIT_FAILURE);
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[821] | 154 |
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[1765] | 155 | switch (b) {
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[821] | 156 | case 'l':
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[2725] | 157 | if (!bb_got_signal) {
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[821] | 158 | do_linemode();
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[2725] | 159 | goto ret;
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[821] | 160 | }
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| 161 | break;
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| 162 | case 'c':
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[2725] | 163 | if (bb_got_signal) {
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[821] | 164 | will_charmode();
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[2725] | 165 | goto ret;
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[821] | 166 | }
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| 167 | break;
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| 168 | case 'z':
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| 169 | cookmode();
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| 170 | kill(0, SIGTSTP);
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| 171 | rawmode();
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| 172 | break;
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| 173 | case 'e':
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[2725] | 174 | doexit(EXIT_SUCCESS);
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[821] | 175 | }
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| 176 |
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[3621] | 177 | full_write1_str("continuing...\r\n");
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[821] | 178 |
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[2725] | 179 | if (bb_got_signal)
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[821] | 180 | cookmode();
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[2725] | 181 | ret:
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| 182 | bb_got_signal = 0;
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[821] | 183 | }
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[1765] | 184 |
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[2725] | 185 | static void handle_net_output(int len)
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[821] | 186 | {
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[2725] | 187 | byte outbuf[2 * DATABUFSIZE];
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[3232] | 188 | byte *dst = outbuf;
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| 189 | byte *src = (byte*)G.buf;
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| 190 | byte *end = src + len;
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[821] | 191 |
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[3232] | 192 | while (src < end) {
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| 193 | byte c = *src++;
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[2725] | 194 | if (c == 0x1d) {
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| 195 | con_escape();
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[821] | 196 | return;
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| 197 | }
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[3232] | 198 | *dst = c;
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[2725] | 199 | if (c == IAC)
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[3232] | 200 | *++dst = c; /* IAC -> IAC IAC */
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| 201 | else
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| 202 | if (c == '\r' || c == '\n') {
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| 203 | /* Enter key sends '\r' in raw mode and '\n' in cooked one.
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| 204 | *
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| 205 | * See RFC 1123 3.3.1 Telnet End-of-Line Convention.
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| 206 | * Using CR LF instead of other allowed possibilities
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| 207 | * like CR NUL - easier to talk to HTTP/SMTP servers.
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| 208 | */
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| 209 | *dst = '\r'; /* Enter -> CR LF */
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| 210 | *++dst = '\n';
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| 211 | }
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| 212 | dst++;
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[821] | 213 | }
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[3232] | 214 | if (dst - outbuf != 0)
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| 215 | full_write(netfd, outbuf, dst - outbuf);
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[821] | 216 | }
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| 217 |
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[2725] | 218 | static void handle_net_input(int len)
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[821] | 219 | {
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| 220 | int i;
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| 221 | int cstart = 0;
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| 222 |
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[2725] | 223 | for (i = 0; i < len; i++) {
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[821] | 224 | byte c = G.buf[i];
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| 225 |
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[2725] | 226 | if (G.telstate == TS_NORMAL) { /* most typical state */
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| 227 | if (c == IAC) {
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[821] | 228 | cstart = i;
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| 229 | G.telstate = TS_IAC;
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| 230 | }
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[2725] | 231 | else if (c == '\r') {
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| 232 | cstart = i + 1;
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| 233 | G.telstate = TS_CR;
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| 234 | }
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| 235 | /* No IACs were seen so far, no need to copy
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| 236 | * bytes within G.buf: */
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| 237 | continue;
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[821] | 238 | }
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| 239 |
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[2725] | 240 | switch (G.telstate) {
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| 241 | case TS_CR:
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| 242 | /* Prev char was CR. If cur one is NUL, ignore it.
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| 243 | * See RFC 1123 section 3.3.1 for discussion of telnet EOL handling.
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| 244 | */
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| 245 | G.telstate = TS_COPY;
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| 246 | if (c == '\0')
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| 247 | break;
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| 248 | /* else: fall through - need to handle CR IAC ... properly */
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| 249 |
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| 250 | case TS_COPY: /* Prev char was ordinary */
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| 251 | /* Similar to NORMAL, but in TS_COPY we need to copy bytes */
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| 252 | if (c == IAC)
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| 253 | G.telstate = TS_IAC;
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| 254 | else
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| 255 | G.buf[cstart++] = c;
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| 256 | if (c == '\r')
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| 257 | G.telstate = TS_CR;
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| 258 | break;
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| 259 |
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| 260 | case TS_IAC: /* Prev char was IAC */
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| 261 | if (c == IAC) { /* IAC IAC -> one IAC */
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| 262 | G.buf[cstart++] = 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 | /* else */
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| 267 | switch (c) {
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| 268 | case SB:
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| 269 | G.telstate = TS_SUB1;
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| 270 | break;
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| 271 | case DO:
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| 272 | case DONT:
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| 273 | case WILL:
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| 274 | case WONT:
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| 275 | G.telwish = c;
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| 276 | G.telstate = TS_OPT;
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| 277 | break;
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| 278 | /* DATA MARK must be added later */
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| 279 | default:
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| 280 | G.telstate = TS_COPY;
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| 281 | }
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| 282 | break;
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| 283 |
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| 284 | case TS_OPT: /* Prev chars were IAC WILL/WONT/DO/DONT */
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| 285 | telopt(c);
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| 286 | G.telstate = TS_COPY;
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| 287 | break;
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| 288 |
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| 289 | case TS_SUB1: /* Subnegotiation */
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| 290 | case TS_SUB2: /* Subnegotiation */
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| 291 | subneg(c); /* can change G.telstate */
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| 292 | break;
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| 293 | }
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[821] | 294 | }
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| 295 |
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[2725] | 296 | if (G.telstate != TS_NORMAL) {
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| 297 | /* We had some IACs, or CR */
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| 298 | if (G.iaclen)
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| 299 | iac_flush();
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| 300 | if (G.telstate == TS_COPY) /* we aren't in the middle of IAC */
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| 301 | G.telstate = TS_NORMAL;
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[821] | 302 | len = cstart;
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| 303 | }
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| 304 |
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| 305 | if (len)
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[2725] | 306 | full_write(STDOUT_FILENO, G.buf, len);
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[821] | 307 | }
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| 308 |
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[2725] | 309 | static void put_iac(int c)
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[821] | 310 | {
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| 311 | G.iacbuf[G.iaclen++] = c;
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| 312 | }
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| 313 |
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[2725] | 314 | static void put_iac2(byte wwdd, byte c)
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[821] | 315 | {
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| 316 | if (G.iaclen + 3 > IACBUFSIZE)
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[2725] | 317 | iac_flush();
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[821] | 318 |
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[2725] | 319 | put_iac(IAC);
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| 320 | put_iac(wwdd);
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| 321 | put_iac(c);
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[821] | 322 | }
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| 323 |
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[1765] | 324 | #if ENABLE_FEATURE_TELNET_TTYPE
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[2725] | 325 | static void put_iac_subopt(byte c, char *str)
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[821] | 326 | {
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[2725] | 327 | int len = strlen(str) + 6; // ( 2 + 1 + 1 + strlen + 2 )
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[821] | 328 |
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| 329 | if (G.iaclen + len > IACBUFSIZE)
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[2725] | 330 | iac_flush();
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[821] | 331 |
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[2725] | 332 | put_iac(IAC);
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| 333 | put_iac(SB);
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| 334 | put_iac(c);
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| 335 | put_iac(0);
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[821] | 336 |
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[1765] | 337 | while (*str)
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[2725] | 338 | put_iac(*str++);
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[821] | 339 |
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[2725] | 340 | put_iac(IAC);
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| 341 | put_iac(SE);
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[821] | 342 | }
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| 343 | #endif
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| 344 |
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[1765] | 345 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
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[2725] | 346 | static void put_iac_subopt_autologin(void)
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[821] | 347 | {
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[1765] | 348 | int len = strlen(G.autologin) + 6; // (2 + 1 + 1 + strlen + 2)
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[2725] | 349 | const char *p = "USER";
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[821] | 350 |
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| 351 | if (G.iaclen + len > IACBUFSIZE)
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[2725] | 352 | iac_flush();
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[821] | 353 |
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[2725] | 354 | put_iac(IAC);
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| 355 | put_iac(SB);
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| 356 | put_iac(TELOPT_NEW_ENVIRON);
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| 357 | put_iac(TELQUAL_IS);
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| 358 | put_iac(NEW_ENV_VAR);
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[821] | 359 |
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[2725] | 360 | while (*p)
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| 361 | put_iac(*p++);
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[821] | 362 |
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[2725] | 363 | put_iac(NEW_ENV_VALUE);
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[821] | 364 |
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[2725] | 365 | p = G.autologin;
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| 366 | while (*p)
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| 367 | put_iac(*p++);
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[821] | 368 |
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[2725] | 369 | put_iac(IAC);
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| 370 | put_iac(SE);
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[821] | 371 | }
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| 372 | #endif
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| 373 |
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[1765] | 374 | #if ENABLE_FEATURE_AUTOWIDTH
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[2725] | 375 | static void put_iac_naws(byte c, int x, int y)
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[821] | 376 | {
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| 377 | if (G.iaclen + 9 > IACBUFSIZE)
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[2725] | 378 | iac_flush();
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[821] | 379 |
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[2725] | 380 | put_iac(IAC);
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| 381 | put_iac(SB);
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| 382 | put_iac(c);
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[821] | 383 |
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[3621] | 384 | /* "... & 0xff" implicitly done below */
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| 385 | put_iac(x >> 8);
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| 386 | put_iac(x);
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| 387 | put_iac(y >> 8);
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| 388 | put_iac(y);
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[821] | 389 |
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[2725] | 390 | put_iac(IAC);
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| 391 | put_iac(SE);
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[821] | 392 | }
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| 393 | #endif
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| 394 |
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| 395 | static void setConMode(void)
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| 396 | {
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[1765] | 397 | if (G.telflags & UF_ECHO) {
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[821] | 398 | if (G.charmode == CHM_TRY) {
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| 399 | G.charmode = CHM_ON;
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[3232] | 400 | printf("\r\nEntering %s mode"
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| 401 | "\r\nEscape character is '^%c'.\r\n", "character", ']');
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[821] | 402 | rawmode();
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| 403 | }
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[1765] | 404 | } else {
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[821] | 405 | if (G.charmode != CHM_OFF) {
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| 406 | G.charmode = CHM_OFF;
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[3232] | 407 | printf("\r\nEntering %s mode"
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| 408 | "\r\nEscape character is '^%c'.\r\n", "line", 'C');
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[821] | 409 | cookmode();
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| 410 | }
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| 411 | }
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| 412 | }
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| 413 |
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| 414 | static void will_charmode(void)
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| 415 | {
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| 416 | G.charmode = CHM_TRY;
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| 417 | G.telflags |= (UF_ECHO | UF_SGA);
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| 418 | setConMode();
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| 419 |
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[2725] | 420 | put_iac2(DO, TELOPT_ECHO);
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| 421 | put_iac2(DO, TELOPT_SGA);
|
---|
| 422 | iac_flush();
|
---|
[821] | 423 | }
|
---|
| 424 |
|
---|
| 425 | static void do_linemode(void)
|
---|
| 426 | {
|
---|
| 427 | G.charmode = CHM_TRY;
|
---|
| 428 | G.telflags &= ~(UF_ECHO | UF_SGA);
|
---|
| 429 | setConMode();
|
---|
| 430 |
|
---|
[2725] | 431 | put_iac2(DONT, TELOPT_ECHO);
|
---|
| 432 | put_iac2(DONT, TELOPT_SGA);
|
---|
| 433 | iac_flush();
|
---|
[821] | 434 | }
|
---|
| 435 |
|
---|
[1765] | 436 | static void to_notsup(char c)
|
---|
[821] | 437 | {
|
---|
[1765] | 438 | if (G.telwish == WILL)
|
---|
[2725] | 439 | put_iac2(DONT, c);
|
---|
[1765] | 440 | else if (G.telwish == DO)
|
---|
[2725] | 441 | put_iac2(WONT, c);
|
---|
[821] | 442 | }
|
---|
| 443 |
|
---|
[1765] | 444 | static void to_echo(void)
|
---|
[821] | 445 | {
|
---|
| 446 | /* if server requests ECHO, don't agree */
|
---|
[1765] | 447 | if (G.telwish == DO) {
|
---|
[2725] | 448 | put_iac2(WONT, TELOPT_ECHO);
|
---|
[1765] | 449 | return;
|
---|
| 450 | }
|
---|
| 451 | if (G.telwish == DONT)
|
---|
| 452 | return;
|
---|
[821] | 453 |
|
---|
[1765] | 454 | if (G.telflags & UF_ECHO) {
|
---|
[821] | 455 | if (G.telwish == WILL)
|
---|
| 456 | return;
|
---|
[1765] | 457 | } else if (G.telwish == WONT)
|
---|
| 458 | return;
|
---|
[821] | 459 |
|
---|
| 460 | if (G.charmode != CHM_OFF)
|
---|
| 461 | G.telflags ^= UF_ECHO;
|
---|
| 462 |
|
---|
| 463 | if (G.telflags & UF_ECHO)
|
---|
[2725] | 464 | put_iac2(DO, TELOPT_ECHO);
|
---|
[821] | 465 | else
|
---|
[2725] | 466 | put_iac2(DONT, TELOPT_ECHO);
|
---|
[821] | 467 |
|
---|
| 468 | setConMode();
|
---|
[2725] | 469 | full_write1_str("\r\n"); /* sudden modec */
|
---|
[821] | 470 | }
|
---|
| 471 |
|
---|
[1765] | 472 | static void to_sga(void)
|
---|
[821] | 473 | {
|
---|
| 474 | /* daemon always sends will/wont, client do/dont */
|
---|
| 475 |
|
---|
[1765] | 476 | if (G.telflags & UF_SGA) {
|
---|
[821] | 477 | if (G.telwish == WILL)
|
---|
| 478 | return;
|
---|
[1765] | 479 | } else if (G.telwish == WONT)
|
---|
| 480 | return;
|
---|
[821] | 481 |
|
---|
[2725] | 482 | G.telflags ^= UF_SGA; /* toggle */
|
---|
| 483 | if (G.telflags & UF_SGA)
|
---|
| 484 | put_iac2(DO, TELOPT_SGA);
|
---|
[821] | 485 | else
|
---|
[2725] | 486 | put_iac2(DONT, TELOPT_SGA);
|
---|
[821] | 487 | }
|
---|
| 488 |
|
---|
[1765] | 489 | #if ENABLE_FEATURE_TELNET_TTYPE
|
---|
| 490 | static void to_ttype(void)
|
---|
[821] | 491 | {
|
---|
| 492 | /* Tell server we will (or won't) do TTYPE */
|
---|
[1765] | 493 | if (G.ttype)
|
---|
[2725] | 494 | put_iac2(WILL, TELOPT_TTYPE);
|
---|
[821] | 495 | else
|
---|
[2725] | 496 | put_iac2(WONT, TELOPT_TTYPE);
|
---|
[821] | 497 | }
|
---|
| 498 | #endif
|
---|
| 499 |
|
---|
[1765] | 500 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
|
---|
| 501 | static void to_new_environ(void)
|
---|
[821] | 502 | {
|
---|
| 503 | /* Tell server we will (or will not) do AUTOLOGIN */
|
---|
[1765] | 504 | if (G.autologin)
|
---|
[2725] | 505 | put_iac2(WILL, TELOPT_NEW_ENVIRON);
|
---|
[821] | 506 | else
|
---|
[2725] | 507 | put_iac2(WONT, TELOPT_NEW_ENVIRON);
|
---|
[821] | 508 | }
|
---|
| 509 | #endif
|
---|
| 510 |
|
---|
[1765] | 511 | #if ENABLE_FEATURE_AUTOWIDTH
|
---|
| 512 | static void to_naws(void)
|
---|
[821] | 513 | {
|
---|
| 514 | /* Tell server we will do NAWS */
|
---|
[2725] | 515 | put_iac2(WILL, TELOPT_NAWS);
|
---|
[821] | 516 | }
|
---|
| 517 | #endif
|
---|
| 518 |
|
---|
| 519 | static void telopt(byte c)
|
---|
| 520 | {
|
---|
[1765] | 521 | switch (c) {
|
---|
| 522 | case TELOPT_ECHO:
|
---|
| 523 | to_echo(); break;
|
---|
| 524 | case TELOPT_SGA:
|
---|
| 525 | to_sga(); break;
|
---|
| 526 | #if ENABLE_FEATURE_TELNET_TTYPE
|
---|
| 527 | case TELOPT_TTYPE:
|
---|
| 528 | to_ttype(); break;
|
---|
[821] | 529 | #endif
|
---|
[1765] | 530 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
|
---|
| 531 | case TELOPT_NEW_ENVIRON:
|
---|
| 532 | to_new_environ(); break;
|
---|
[821] | 533 | #endif
|
---|
[1765] | 534 | #if ENABLE_FEATURE_AUTOWIDTH
|
---|
| 535 | case TELOPT_NAWS:
|
---|
| 536 | to_naws();
|
---|
[2725] | 537 | put_iac_naws(c, G.win_width, G.win_height);
|
---|
[1765] | 538 | break;
|
---|
[821] | 539 | #endif
|
---|
[1765] | 540 | default:
|
---|
| 541 | to_notsup(c);
|
---|
| 542 | break;
|
---|
[821] | 543 | }
|
---|
| 544 | }
|
---|
| 545 |
|
---|
| 546 | /* subnegotiation -- ignore all (except TTYPE,NAWS) */
|
---|
[2725] | 547 | static void subneg(byte c)
|
---|
[821] | 548 | {
|
---|
[1765] | 549 | switch (G.telstate) {
|
---|
[821] | 550 | case TS_SUB1:
|
---|
| 551 | if (c == IAC)
|
---|
| 552 | G.telstate = TS_SUB2;
|
---|
[1765] | 553 | #if ENABLE_FEATURE_TELNET_TTYPE
|
---|
[821] | 554 | else
|
---|
[2725] | 555 | if (c == TELOPT_TTYPE && G.ttype)
|
---|
| 556 | put_iac_subopt(TELOPT_TTYPE, G.ttype);
|
---|
[821] | 557 | #endif
|
---|
[1765] | 558 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
|
---|
[821] | 559 | else
|
---|
[2725] | 560 | if (c == TELOPT_NEW_ENVIRON && G.autologin)
|
---|
| 561 | put_iac_subopt_autologin();
|
---|
[821] | 562 | #endif
|
---|
| 563 | break;
|
---|
| 564 | case TS_SUB2:
|
---|
[2725] | 565 | if (c == SE) {
|
---|
| 566 | G.telstate = TS_COPY;
|
---|
| 567 | return;
|
---|
| 568 | }
|
---|
[821] | 569 | G.telstate = TS_SUB1;
|
---|
[2725] | 570 | break;
|
---|
[821] | 571 | }
|
---|
| 572 | }
|
---|
| 573 |
|
---|
| 574 | static void rawmode(void)
|
---|
| 575 | {
|
---|
[1765] | 576 | if (G.do_termios)
|
---|
| 577 | tcsetattr(0, TCSADRAIN, &G.termios_raw);
|
---|
[821] | 578 | }
|
---|
| 579 |
|
---|
| 580 | static void cookmode(void)
|
---|
| 581 | {
|
---|
[1765] | 582 | if (G.do_termios)
|
---|
| 583 | tcsetattr(0, TCSADRAIN, &G.termios_def);
|
---|
[821] | 584 | }
|
---|
| 585 |
|
---|
[2725] | 586 | int telnet_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
---|
| 587 | int telnet_main(int argc UNUSED_PARAM, char **argv)
|
---|
[821] | 588 | {
|
---|
[1765] | 589 | char *host;
|
---|
| 590 | int port;
|
---|
[821] | 591 | int len;
|
---|
| 592 | struct pollfd ufds[2];
|
---|
| 593 |
|
---|
[1765] | 594 | INIT_G();
|
---|
| 595 |
|
---|
| 596 | #if ENABLE_FEATURE_AUTOWIDTH
|
---|
| 597 | get_terminal_width_height(0, &G.win_width, &G.win_height);
|
---|
[821] | 598 | #endif
|
---|
| 599 |
|
---|
[1765] | 600 | #if ENABLE_FEATURE_TELNET_TTYPE
|
---|
| 601 | G.ttype = getenv("TERM");
|
---|
[821] | 602 | #endif
|
---|
| 603 |
|
---|
| 604 | if (tcgetattr(0, &G.termios_def) >= 0) {
|
---|
| 605 | G.do_termios = 1;
|
---|
| 606 | G.termios_raw = G.termios_def;
|
---|
| 607 | cfmakeraw(&G.termios_raw);
|
---|
| 608 | }
|
---|
| 609 |
|
---|
[1765] | 610 | #if ENABLE_FEATURE_TELNET_AUTOLOGIN
|
---|
| 611 | if (1 & getopt32(argv, "al:", &G.autologin))
|
---|
| 612 | G.autologin = getenv("USER");
|
---|
| 613 | argv += optind;
|
---|
[821] | 614 | #else
|
---|
[1765] | 615 | argv++;
|
---|
[821] | 616 | #endif
|
---|
[1765] | 617 | if (!*argv)
|
---|
| 618 | bb_show_usage();
|
---|
| 619 | host = *argv++;
|
---|
| 620 | port = bb_lookup_port(*argv ? *argv++ : "telnet", "tcp", 23);
|
---|
| 621 | if (*argv) /* extra params?? */
|
---|
| 622 | bb_show_usage();
|
---|
[821] | 623 |
|
---|
[2725] | 624 | xmove_fd(create_and_connect_stream_or_die(host, port), netfd);
|
---|
[821] | 625 |
|
---|
[3621] | 626 | setsockopt_keepalive(netfd);
|
---|
[821] | 627 |
|
---|
[2725] | 628 | signal(SIGINT, record_signo);
|
---|
[821] | 629 |
|
---|
[2725] | 630 | ufds[0].fd = STDIN_FILENO;
|
---|
| 631 | ufds[0].events = POLLIN;
|
---|
| 632 | ufds[1].fd = netfd;
|
---|
| 633 | ufds[1].events = POLLIN;
|
---|
[821] | 634 |
|
---|
[1765] | 635 | while (1) {
|
---|
[2725] | 636 | if (poll(ufds, 2, -1) < 0) {
|
---|
[821] | 637 | /* error, ignore and/or log something, bay go to loop */
|
---|
[2725] | 638 | if (bb_got_signal)
|
---|
| 639 | con_escape();
|
---|
[821] | 640 | else
|
---|
| 641 | sleep(1);
|
---|
[2725] | 642 | continue;
|
---|
| 643 | }
|
---|
[821] | 644 |
|
---|
[2725] | 645 | // FIXME: reads can block. Need full bidirectional buffering.
|
---|
[821] | 646 |
|
---|
[2725] | 647 | if (ufds[0].revents) {
|
---|
| 648 | len = safe_read(STDIN_FILENO, G.buf, DATABUFSIZE);
|
---|
| 649 | if (len <= 0)
|
---|
| 650 | doexit(EXIT_SUCCESS);
|
---|
| 651 | TRACE(0, ("Read con: %d\n", len));
|
---|
| 652 | handle_net_output(len);
|
---|
| 653 | }
|
---|
| 654 |
|
---|
| 655 | if (ufds[1].revents) {
|
---|
| 656 | len = safe_read(netfd, G.buf, DATABUFSIZE);
|
---|
| 657 | if (len <= 0) {
|
---|
| 658 | full_write1_str("Connection closed by foreign host\r\n");
|
---|
| 659 | doexit(EXIT_FAILURE);
|
---|
[821] | 660 | }
|
---|
[2725] | 661 | TRACE(0, ("Read netfd (%d): %d\n", netfd, len));
|
---|
| 662 | handle_net_input(len);
|
---|
[821] | 663 | }
|
---|
[2725] | 664 | } /* while (1) */
|
---|
[821] | 665 | }
|
---|