* <jam@ltsp.org>
* Modified 2004/02/11 to add ability to pass the USER variable to remote host
* by Fernando Silveira <swrh@gmx.net>
- *
*/
+//config:config TELNET
+//config: bool "telnet (8.7 kb)"
+//config: default y
+//config: help
+//config: Telnet is an interface to the TELNET protocol, but is also commonly
+//config: used to test other simple protocols.
+//config:
+//config:config FEATURE_TELNET_TTYPE
+//config: bool "Pass TERM type to remote host"
+//config: default y
+//config: depends on TELNET
+//config: help
+//config: Setting this option will forward the TERM environment variable to the
+//config: remote host you are connecting to. This is useful to make sure that
+//config: things like ANSI colors and other control sequences behave.
+//config:
+//config:config FEATURE_TELNET_AUTOLOGIN
+//config: bool "Pass USER type to remote host"
+//config: default y
+//config: depends on TELNET
+//config: help
+//config: Setting this option will forward the USER environment variable to the
+//config: remote host you are connecting to. This is useful when you need to
+//config: log into a machine without telling the username (autologin). This
+//config: option enables '-a' and '-l USER' options.
+//config:
+//config:config FEATURE_TELNET_WIDTH
+//config: bool "Enable window size autodetection"
+//config: default y
+//config: depends on TELNET
+
+//applet:IF_TELNET(APPLET(telnet, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_TELNET) += telnet.o
+
+//usage:#if ENABLE_FEATURE_TELNET_AUTOLOGIN
+//usage:#define telnet_trivial_usage
+//usage: "[-a] [-l USER] HOST [PORT]"
+//usage:#define telnet_full_usage "\n\n"
+//usage: "Connect to telnet server\n"
+//usage: "\n -a Automatic login with $USER variable"
+//usage: "\n -l USER Automatic login as USER"
+//usage:
+//usage:#else
+//usage:#define telnet_trivial_usage
+//usage: "HOST [PORT]"
+//usage:#define telnet_full_usage "\n\n"
+//usage: "Connect to telnet server"
+//usage:#endif
#include <arpa/telnet.h>
#include <netinet/in.h>
#include "libbb.h"
+#include "common_bufsiz.h"
+
+#ifdef __BIONIC__
+/* should be in arpa/telnet.h */
+# define IAC 255 /* interpret as command: */
+# define DONT 254 /* you are not to use option */
+# define DO 253 /* please, you use option */
+# define WONT 252 /* I won't use option */
+# define WILL 251 /* I will use option */
+# define SB 250 /* interpret as subnegotiation */
+# define SE 240 /* end sub negotiation */
+# define TELOPT_ECHO 1 /* echo */
+# define TELOPT_SGA 3 /* suppress go ahead */
+# define TELOPT_TTYPE 24 /* terminal type */
+# define TELOPT_NAWS 31 /* window size */
+#endif
#ifdef DOTRACE
-#define TRACE(x, y) do { if (x) printf y; } while (0)
+# define TRACE(x, y) do { if (x) printf y; } while (0)
#else
-#define TRACE(x, y)
+# define TRACE(x, y)
#endif
enum {
#if ENABLE_FEATURE_TELNET_AUTOLOGIN
const char *autologin;
#endif
-#if ENABLE_FEATURE_AUTOWIDTH
+#if ENABLE_FEATURE_TELNET_WIDTH
unsigned win_width, win_height;
#endif
/* same buffer used both for network and console read/write */
struct termios termios_def;
struct termios termios_raw;
} FIX_ALIASING;
-#define G (*(struct globals*)&bb_common_bufsiz1)
+#define G (*(struct globals*)bb_common_bufsiz1)
#define INIT_G() do { \
- struct G_sizecheck { \
- char G_sizecheck[sizeof(G) > COMMON_BUFSIZE ? -1 : 1]; \
- }; \
+ setup_common_bufsiz(); \
+ BUILD_BUG_ON(sizeof(G) > COMMON_BUFSIZE); \
} while (0)
static void iac_flush(void)
{
- write(netfd, G.iacbuf, G.iaclen);
+ full_write(netfd, G.iacbuf, G.iaclen);
G.iaclen = 0;
}
-#define write_str(fd, str) write(fd, str, sizeof(str) - 1)
-
static void doexit(int ev) NORETURN;
static void doexit(int ev)
{
if (bb_got_signal) /* came from line mode... go raw */
rawmode();
- write_str(1, "\r\nConsole escape. Commands are:\r\n\n"
+ full_write1_str("\r\nConsole escape. Commands are:\r\n\n"
" l go to line mode\r\n"
" c go to character mode\r\n"
" z suspend telnet\r\n"
doexit(EXIT_SUCCESS);
}
- write_str(1, "continuing...\r\n");
+ full_write1_str("continuing...\r\n");
if (bb_got_signal)
cookmode();
static void handle_net_output(int len)
{
- /* here we could do smart tricks how to handle 0xFF:s in output
- * stream like writing twice every sequence of FF:s (thus doing
- * many write()s. But I think interactive telnet application does
- * not need to be 100% 8-bit clean, so changing every 0xff:s to
- * 0x7f:s
- *
- * 2002-mar-21, Przemyslaw Czerpak (druzus@polbox.com)
- * I don't agree.
- * first - I cannot use programs like sz/rz
- * second - the 0x0D is sent as one character and if the next
- * char is 0x0A then it's eaten by a server side.
- * third - why do you have to make 'many write()s'?
- * I don't understand.
- * So I implemented it. It's really useful for me. I hope that
- * other people will find it interesting too.
- */
byte outbuf[2 * DATABUFSIZE];
- byte *p = (byte*)G.buf;
- int j = 0;
+ byte *dst = outbuf;
+ byte *src = (byte*)G.buf;
+ byte *end = src + len;
- for (; len > 0; len--, p++) {
- byte c = *p;
+ while (src < end) {
+ byte c = *src++;
if (c == 0x1d) {
con_escape();
return;
}
- outbuf[j++] = c;
+ *dst = c;
if (c == IAC)
- outbuf[j++] = c; /* IAC -> IAC IAC */
- else if (c == '\r')
- outbuf[j++] = '\0'; /* CR -> CR NUL */
+ *++dst = c; /* IAC -> IAC IAC */
+ else
+ if (c == '\r' || c == '\n') {
+ /* Enter key sends '\r' in raw mode and '\n' in cooked one.
+ *
+ * See RFC 1123 3.3.1 Telnet End-of-Line Convention.
+ * Using CR LF instead of other allowed possibilities
+ * like CR NUL - easier to talk to HTTP/SMTP servers.
+ */
+ *dst = '\r'; /* Enter -> CR LF */
+ *++dst = '\n';
+ }
+ dst++;
}
- if (j > 0)
- full_write(netfd, outbuf, j);
+ if (dst - outbuf != 0)
+ full_write(netfd, outbuf, dst - outbuf);
}
static void handle_net_input(int len)
G.iacbuf[G.iaclen++] = c;
}
-static void put_iac2(byte wwdd, byte c)
+static void put_iac2_merged(unsigned wwdd_and_c)
{
if (G.iaclen + 3 > IACBUFSIZE)
iac_flush();
put_iac(IAC);
- put_iac(wwdd);
- put_iac(c);
+ put_iac(wwdd_and_c >> 8);
+ put_iac(wwdd_and_c & 0xff);
}
+#define put_iac2(wwdd,c) put_iac2_merged(((wwdd)<<8) + (c))
#if ENABLE_FEATURE_TELNET_TTYPE
static void put_iac_subopt(byte c, char *str)
}
#endif
-#if ENABLE_FEATURE_AUTOWIDTH
+#if ENABLE_FEATURE_TELNET_WIDTH
static void put_iac_naws(byte c, int x, int y)
{
if (G.iaclen + 9 > IACBUFSIZE)
put_iac(SB);
put_iac(c);
- put_iac((x >> 8) & 0xff);
- put_iac(x & 0xff);
- put_iac((y >> 8) & 0xff);
- put_iac(y & 0xff);
+ /* "... & 0xff" implicitly done below */
+ put_iac(x >> 8);
+ put_iac(x);
+ put_iac(y >> 8);
+ put_iac(y);
put_iac(IAC);
put_iac(SE);
}
#endif
-static char const escapecharis[] ALIGN1 = "\r\nEscape character is ";
-
static void setConMode(void)
{
if (G.telflags & UF_ECHO) {
if (G.charmode == CHM_TRY) {
G.charmode = CHM_ON;
- printf("\r\nEntering character mode%s'^]'.\r\n", escapecharis);
+ printf("\r\nEntering %s mode"
+ "\r\nEscape character is '^%c'.\r\n", "character", ']');
rawmode();
}
} else {
if (G.charmode != CHM_OFF) {
G.charmode = CHM_OFF;
- printf("\r\nEntering line mode%s'^C'.\r\n", escapecharis);
+ printf("\r\nEntering %s mode"
+ "\r\nEscape character is '^%c'.\r\n", "line", 'C');
cookmode();
}
}
}
#endif
-#if ENABLE_FEATURE_AUTOWIDTH
+#if ENABLE_FEATURE_TELNET_WIDTH
static void to_naws(void)
{
/* Tell server we will do NAWS */
case TELOPT_NEW_ENVIRON:
to_new_environ(); break;
#endif
-#if ENABLE_FEATURE_AUTOWIDTH
+#if ENABLE_FEATURE_TELNET_WIDTH
case TELOPT_NAWS:
to_naws();
put_iac_naws(c, G.win_width, G.win_height);
INIT_G();
-#if ENABLE_FEATURE_AUTOWIDTH
+#if ENABLE_FEATURE_TELNET_WIDTH
get_terminal_width_height(0, &G.win_width, &G.win_height);
#endif
}
#if ENABLE_FEATURE_TELNET_AUTOLOGIN
- if (1 & getopt32(argv, "al:", &G.autologin))
+ if (1 == getopt32(argv, "al:", &G.autologin)) {
+ /* Only -a without -l USER picks $USER from envvar */
G.autologin = getenv("USER");
+ }
argv += optind;
#else
argv++;
xmove_fd(create_and_connect_stream_or_die(host, port), netfd);
- setsockopt(netfd, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
+ setsockopt_keepalive(netfd);
signal(SIGINT, record_signo);
projects / oweals / busybox.git / blobdiff