From ae92cbd542086a508343dd88fd3b980f3be1b3af Mon Sep 17 00:00:00 2001 From: Jing Liu Date: Fri, 23 Sep 2016 08:06:11 +0200 Subject: chardev: Basic support for TN3270 This introduces basic support for TN3270, which needs to negotiate three Telnet options during handshake: - End of Record - Binary Transmission - Terminal-Type As a basic implementation, this simply ignores NOP and Interrupt Process(IP) commands. More work should be done for them later. For more details, please refer to RFC 854 and 1576. Signed-off-by: Jing Liu Signed-off-by: Yang Chen Reviewed-by: QingFeng Hao Acked-by: Dong Jia Shi Signed-off-by: Cornelia Huck Reviewed-by: Marc-André Lureau --- chardev/char-socket.c | 76 +++++++++++++++++++++++++++++++++++++-------------- chardev/char.c | 11 ++++++-- 2 files changed, 65 insertions(+), 22 deletions(-) (limited to 'chardev') diff --git a/chardev/char-socket.c b/chardev/char-socket.c index 36ab0d633a..175fb8c3ec 100644 --- a/chardev/char-socket.c +++ b/chardev/char-socket.c @@ -55,6 +55,7 @@ typedef struct { SocketAddress *addr; bool is_listen; bool is_telnet; + bool is_tn3270; guint reconnect_timer; int64_t reconnect_time; @@ -141,19 +142,25 @@ static int tcp_chr_read_poll(void *opaque) return s->max_size; } -#define IAC 255 -#define IAC_BREAK 243 static void tcp_chr_process_IAC_bytes(Chardev *chr, SocketChardev *s, uint8_t *buf, int *size) { - /* Handle any telnet client's basic IAC options to satisfy char by - * char mode with no echo. All IAC options will be removed from - * the buf and the do_telnetopt variable will be used to track the - * state of the width of the IAC information. + /* Handle any telnet or tn3270 client's basic IAC options. + * For telnet options, it satisfies char by char mode with no echo. + * For tn3270 options, it satisfies binary mode with EOR. + * All IAC options will be removed from the buf and the do_opt + * pointer will be used to track the state of the width of the + * IAC information. * - * IAC commands come in sets of 3 bytes with the exception of the - * "IAC BREAK" command and the double IAC. + * RFC854: "All TELNET commands consist of at least a two byte sequence. + * The commands dealing with option negotiation are three byte sequences, + * the third byte being the code for the option referenced." + * "IAC BREAK", "IAC IP", "IAC NOP" and the double IAC are two bytes. + * "IAC SB", "IAC SE" and "IAC EOR" are saved to split up data boundary + * for tn3270. + * NOP, Break and Interrupt Process(IP) might be encountered during a TN3270 + * session, and NOP and IP need to be done later. */ int i; @@ -174,6 +181,18 @@ static void tcp_chr_process_IAC_bytes(Chardev *chr, /* Handle IAC break commands by sending a serial break */ qemu_chr_be_event(chr, CHR_EVENT_BREAK); s->do_telnetopt++; + } else if (s->is_tn3270 && ((unsigned char)buf[i] == IAC_EOR + || (unsigned char)buf[i] == IAC_SB + || (unsigned char)buf[i] == IAC_SE) + && s->do_telnetopt == 2) { + buf[j++] = IAC; + buf[j++] = buf[i]; + s->do_telnetopt++; + } else if (s->is_tn3270 && ((unsigned char)buf[i] == IAC_IP + || (unsigned char)buf[i] == IAC_NOP) + && s->do_telnetopt == 2) { + /* TODO: IP and NOP need to be implemented later. */ + s->do_telnetopt++; } s->do_telnetopt++; } @@ -512,7 +531,7 @@ static void tcp_chr_update_read_handler(Chardev *chr, typedef struct { Chardev *chr; - char buf[12]; + char buf[21]; size_t buflen; } TCPChardevTelnetInit; @@ -550,9 +569,6 @@ static void tcp_chr_telnet_init(Chardev *chr) TCPChardevTelnetInit *init = g_new0(TCPChardevTelnetInit, 1); size_t n = 0; - init->chr = chr; - init->buflen = 12; - #define IACSET(x, a, b, c) \ do { \ x[n++] = a; \ @@ -560,12 +576,26 @@ static void tcp_chr_telnet_init(Chardev *chr) x[n++] = c; \ } while (0) - /* Prep the telnet negotion to put telnet in binary, - * no echo, single char mode */ - IACSET(init->buf, 0xff, 0xfb, 0x01); /* IAC WILL ECHO */ - IACSET(init->buf, 0xff, 0xfb, 0x03); /* IAC WILL Suppress go ahead */ - IACSET(init->buf, 0xff, 0xfb, 0x00); /* IAC WILL Binary */ - IACSET(init->buf, 0xff, 0xfd, 0x00); /* IAC DO Binary */ + init->chr = chr; + if (!s->is_tn3270) { + init->buflen = 12; + /* Prep the telnet negotion to put telnet in binary, + * no echo, single char mode */ + IACSET(init->buf, 0xff, 0xfb, 0x01); /* IAC WILL ECHO */ + IACSET(init->buf, 0xff, 0xfb, 0x03); /* IAC WILL Suppress go ahead */ + IACSET(init->buf, 0xff, 0xfb, 0x00); /* IAC WILL Binary */ + IACSET(init->buf, 0xff, 0xfd, 0x00); /* IAC DO Binary */ + } else { + init->buflen = 21; + /* Prep the TN3270 negotion based on RFC1576 */ + IACSET(init->buf, 0xff, 0xfd, 0x19); /* IAC DO EOR */ + IACSET(init->buf, 0xff, 0xfb, 0x19); /* IAC WILL EOR */ + IACSET(init->buf, 0xff, 0xfd, 0x00); /* IAC DO BINARY */ + IACSET(init->buf, 0xff, 0xfb, 0x00); /* IAC WILL BINARY */ + IACSET(init->buf, 0xff, 0xfd, 0x18); /* IAC DO TERMINAL TYPE */ + IACSET(init->buf, 0xff, 0xfa, 0x18); /* IAC SB TERMINAL TYPE */ + IACSET(init->buf, 0x01, 0xff, 0xf0); /* SEND IAC SE */ + } #undef IACSET @@ -585,7 +615,8 @@ static void tcp_chr_tls_handshake(QIOTask *task, if (qio_task_propagate_error(task, NULL)) { tcp_chr_disconnect(chr); } else { - if (s->do_telnetopt) { + /* tn3270 does not support TLS yet */ + if (s->do_telnetopt && !s->is_tn3270) { tcp_chr_telnet_init(chr); } else { tcp_chr_connect(chr); @@ -824,12 +855,14 @@ static void qmp_chardev_open_socket(Chardev *chr, bool do_nodelay = sock->has_nodelay ? sock->nodelay : false; bool is_listen = sock->has_server ? sock->server : true; bool is_telnet = sock->has_telnet ? sock->telnet : false; + bool is_tn3270 = sock->has_tn3270 ? sock->tn3270 : false; bool is_waitconnect = sock->has_wait ? sock->wait : false; int64_t reconnect = sock->has_reconnect ? sock->reconnect : 0; QIOChannelSocket *sioc = NULL; s->is_listen = is_listen; s->is_telnet = is_telnet; + s->is_tn3270 = is_tn3270; s->do_nodelay = do_nodelay; if (sock->tls_creds) { Object *creds; @@ -879,7 +912,7 @@ static void qmp_chardev_open_socket(Chardev *chr, addr, is_listen, is_telnet); if (is_listen) { - if (is_telnet) { + if (is_telnet || is_tn3270) { s->do_telnetopt = 1; } } else if (reconnect > 0) { @@ -933,6 +966,7 @@ static void qemu_chr_parse_socket(QemuOpts *opts, ChardevBackend *backend, bool is_listen = qemu_opt_get_bool(opts, "server", false); bool is_waitconnect = is_listen && qemu_opt_get_bool(opts, "wait", true); bool is_telnet = qemu_opt_get_bool(opts, "telnet", false); + bool is_tn3270 = qemu_opt_get_bool(opts, "tn3270", false); bool do_nodelay = !qemu_opt_get_bool(opts, "delay", true); int64_t reconnect = qemu_opt_get_number(opts, "reconnect", 0); const char *path = qemu_opt_get(opts, "path"); @@ -968,6 +1002,8 @@ static void qemu_chr_parse_socket(QemuOpts *opts, ChardevBackend *backend, sock->server = is_listen; sock->has_telnet = true; sock->telnet = is_telnet; + sock->has_tn3270 = true; + sock->tn3270 = is_tn3270; sock->has_wait = true; sock->wait = is_waitconnect; sock->has_reconnect = true; diff --git a/chardev/char.c b/chardev/char.c index 3df116350b..309734f2b7 100644 --- a/chardev/char.c +++ b/chardev/char.c @@ -696,7 +696,8 @@ QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename) return opts; } if (strstart(filename, "tcp:", &p) || - strstart(filename, "telnet:", &p)) { + strstart(filename, "telnet:", &p) || + strstart(filename, "tn3270:", &p)) { if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) { host[0] = 0; if (sscanf(p, ":%32[^,]%n", port, &pos) < 1) @@ -712,8 +713,11 @@ QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename) goto fail; } } - if (strstart(filename, "telnet:", &p)) + if (strstart(filename, "telnet:", &p)) { qemu_opt_set(opts, "telnet", "on", &error_abort); + } else if (strstart(filename, "tn3270:", &p)) { + qemu_opt_set(opts, "tn3270", "on", &error_abort); + } return opts; } if (strstart(filename, "udp:", &p)) { @@ -1176,6 +1180,9 @@ QemuOptsList qemu_chardev_opts = { },{ .name = "telnet", .type = QEMU_OPT_BOOL, + },{ + .name = "tn3270", + .type = QEMU_OPT_BOOL, },{ .name = "tls-creds", .type = QEMU_OPT_STRING, -- cgit v1.2.3-55-g7522