X-Git-Url: https://review.openocd.org/gitweb?p=openocd.git;a=blobdiff_plain;f=src%2Fserver%2Ftelnet_server.c;h=10caee31681948425cd152db037833cd92f43cb1;hp=830cf6410caa953b0316aa1b344a3f546cee6770;hb=4af724df238eb30569c2845b6160ef4e7f894ad1;hpb=7f1944a47823fc48eef244257b80675a226f86b8 diff --git a/src/server/telnet_server.c b/src/server/telnet_server.c index 830cf6410c..10caee3168 100644 --- a/src/server/telnet_server.c +++ b/src/server/telnet_server.c @@ -1,631 +1,634 @@ -/*************************************************************************** - * Copyright (C) 2005 by Dominic Rath * - * Dominic.Rath@gmx.de * - * * - * This program is free software; you can redistribute it and/or modify * - * it under the terms of the GNU General Public License as published by * - * the Free Software Foundation; either version 2 of the License, or * - * (at your option) any later version. * - * * - * This program is distributed in the hope that it will be useful, * - * but WITHOUT ANY WARRANTY; without even the implied warranty of * - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * - * GNU General Public License for more details. * - * * - * You should have received a copy of the GNU General Public License * - * along with this program; if not, write to the * - * Free Software Foundation, Inc., * - * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * - ***************************************************************************/ -#ifdef HAVE_CONFIG_H -#include "config.h" -#endif - -#include "replacements.h" - -#include "telnet_server.h" - -#include "server.h" -#include "log.h" -#include "command.h" -#include "target.h" -#include "target_request.h" - -#include -#include -#include -#include -#include - -static unsigned short telnet_port = 0; - -int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc); -int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc); - -static char *negotiate = - "\xFF\xFB\x03" /* IAC WILL Suppress Go Ahead */ - "\xFF\xFB\x01" /* IAC WILL Echo */ - "\xFF\xFD\x03" /* IAC DO Suppress Go Ahead */ - "\xFF\xFE\x01"; /* IAC DON'T Echo */ - -#define CTRL(c) (c - '@') - -/* The only way we can detect that the socket is closed is the first time - * we write to it, we will fail. Subsequent write operations will - * succeed. Shudder! - */ -int telnet_write(connection_t *connection, void *data, int len) -{ - telnet_connection_t *t_con = connection->priv; - if (t_con->closed) - return ERROR_SERVER_REMOTE_CLOSED; - - if (write_socket(connection->fd, data, len) == len) - { - return ERROR_OK; - } - t_con->closed = 1; - return ERROR_SERVER_REMOTE_CLOSED; -} - -int telnet_prompt(connection_t *connection) -{ - telnet_connection_t *t_con = connection->priv; - - return telnet_write(connection, t_con->prompt, strlen(t_con->prompt)); -} - -int telnet_outputline(connection_t *connection, char* line) -{ - telnet_write(connection, line, strlen(line)); - return telnet_write(connection, "\r\n\0", 3); -} - -int telnet_output(struct command_context_s *cmd_ctx, char* line) -{ - connection_t *connection = cmd_ctx->output_handler_priv; - - return telnet_outputline(connection, line); -} - -void telnet_log_callback(void *priv, const char *file, int line, - const char *function, const char *format, va_list args) -{ - connection_t *connection = priv; - char *t = alloc_printf(format, args); - char *t2; - if (t == NULL) - return; - t2=t; - char *endline; - do - { - if ((endline=strchr(t2, '\n'))!=NULL) - { - *endline=0; - } - telnet_outputline(connection, t2); - t2=endline+1; - } while (endline); - - free(t); -} - -int telnet_target_callback_event_handler(struct target_s *target, enum target_event event, void *priv) -{ - struct command_context_s *cmd_ctx = priv; - connection_t *connection = cmd_ctx->output_handler_priv; - telnet_connection_t *t_con = connection->priv; - - switch (event) - { - case TARGET_EVENT_HALTED: - target_arch_state(target); - if (!t_con->suppress_prompt) - telnet_prompt(connection); - break; - case TARGET_EVENT_RESUMED: - if (!t_con->suppress_prompt) - telnet_prompt(connection); - break; - default: - break; - } - - return ERROR_OK; -} - -int telnet_new_connection(connection_t *connection) -{ - telnet_connection_t *telnet_connection = malloc(sizeof(telnet_connection_t)); - telnet_service_t *telnet_service = connection->service->priv; - int i; - - connection->priv = telnet_connection; - - /* initialize telnet connection information */ - telnet_connection->closed = 0; - telnet_connection->line_size = 0; - telnet_connection->line_cursor = 0; - telnet_connection->option_size = 0; - telnet_connection->prompt = strdup("> "); - telnet_connection->suppress_prompt = 0; - telnet_connection->state = TELNET_STATE_DATA; - - /* output goes through telnet connection */ - command_set_output_handler(connection->cmd_ctx, telnet_output, connection); - - /* negotiate telnet options */ - telnet_write(connection, negotiate, strlen(negotiate)); - - /* print connection banner */ - if (telnet_service->banner) - { - telnet_write(connection, telnet_service->banner, strlen(telnet_service->banner)); - telnet_write(connection, "\r\n\0", 3); - } - - telnet_prompt(connection); - - /* initialize history */ - for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++) - { - telnet_connection->history[i] = NULL; - } - telnet_connection->next_history = 0; - telnet_connection->current_history = 0; - - target_register_event_callback(telnet_target_callback_event_handler, connection->cmd_ctx); - - return ERROR_OK; -} - -void telnet_clear_line(connection_t *connection, telnet_connection_t *t_con) -{ - /* move to end of line */ - if (t_con->line_cursor < t_con->line_size) - { - telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); - } - - /* backspace, overwrite with space, backspace */ - while (t_con->line_size > 0) - { - telnet_write(connection, "\b \b", 3); - t_con->line_size--; - } - t_con->line_cursor = 0; -} - -int telnet_input(connection_t *connection) -{ - int bytes_read; - char buffer[TELNET_BUFFER_SIZE]; - char *buf_p; - telnet_connection_t *t_con = connection->priv; - command_context_t *command_context = connection->cmd_ctx; - - bytes_read = read_socket(connection->fd, buffer, TELNET_BUFFER_SIZE); - - if (bytes_read == 0) - return ERROR_SERVER_REMOTE_CLOSED; - else if (bytes_read == -1) - { - ERROR("error during read: %s", strerror(errno)); - return ERROR_SERVER_REMOTE_CLOSED; - } - - buf_p = buffer; - while (bytes_read) - { - switch (t_con->state) - { - case TELNET_STATE_DATA: - if (*buf_p == '\xff') - { - t_con->state = TELNET_STATE_IAC; - } - else - { - if (isprint(*buf_p)) /* printable character */ - { - telnet_write(connection, buf_p, 1); - if (t_con->line_cursor == t_con->line_size) - { - t_con->line[t_con->line_size++] = *buf_p; - t_con->line_cursor++; - } - else - { - int i; - memmove(t_con->line + t_con->line_cursor + 1, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); - t_con->line[t_con->line_cursor++] = *buf_p; - t_con->line_size++; - telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); - for (i = t_con->line_cursor; i < t_con->line_size; i++) - { - telnet_write(connection, "\b", 1); - } - } - } - else /* non-printable */ - { - if (*buf_p == 0x1b) /* escape */ - { - t_con->state = TELNET_STATE_ESCAPE; - t_con->last_escape = '\x00'; - } - else if ((*buf_p == 0xd) || (*buf_p == 0xa)) /* CR/LF */ - { - int retval; - - /* skip over combinations with CR/LF + NUL */ - if (((*(buf_p + 1) == 0xa) || (*(buf_p + 1) == 0xd)) && (bytes_read > 1)) - { - buf_p++; - bytes_read--; - } - if ((*(buf_p + 1) == 0) && (bytes_read > 1)) - { - buf_p++; - bytes_read--; - } - t_con->line[t_con->line_size] = 0; - - telnet_write(connection, "\r\n\x00", 3); - - if (strcmp(t_con->line, "history") == 0) - { - int i; - for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++) - { - if (t_con->history[i]) - { - telnet_write(connection, t_con->history[i], strlen(t_con->history[i])); - telnet_write(connection, "\r\n\x00", 3); - } - } - telnet_prompt(connection); - t_con->line_size = 0; - t_con->line_cursor = 0; - continue; - } - - log_add_callback(telnet_log_callback, connection); - t_con->suppress_prompt = 1; - - retval = command_run_line(command_context, t_con->line); - - log_remove_callback(telnet_log_callback, connection); - t_con->suppress_prompt = 0; - - if (retval == ERROR_COMMAND_CLOSE_CONNECTION) - { - return ERROR_SERVER_REMOTE_CLOSED; - } - - /* Save only non-blank lines in the history */ - if (t_con->line_size > 0) - { - /* if the history slot is already taken, free it */ - if (t_con->history[t_con->next_history]) - { - free(t_con->history[t_con->next_history]); - } - - /* add line to history */ - t_con->history[t_con->next_history] = strdup(t_con->line); - - /* wrap history at TELNET_LINE_HISTORY_SIZE */ - t_con->next_history = (t_con->next_history + 1) % TELNET_LINE_HISTORY_SIZE; - - /* current history line starts at the new entry */ - t_con->current_history = t_con->next_history; - - if (t_con->history[t_con->current_history]) - { - free(t_con->history[t_con->current_history]); - } - t_con->history[t_con->current_history] = strdup(""); - } - - int t = telnet_prompt(connection); - if (t == ERROR_SERVER_REMOTE_CLOSED) - return t; - - t_con->line_size = 0; - t_con->line_cursor = 0; - } - else if ((*buf_p == 0x7f) || (*buf_p == 0x8)) /* delete character */ - { - if (t_con->line_cursor > 0) - { - if (t_con->line_cursor != t_con->line_size) - { - int i; - telnet_write(connection, "\b", 1); - t_con->line_cursor--; - t_con->line_size--; - memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor); - - telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); - telnet_write(connection, " \b", 2); - for (i = t_con->line_cursor; i < t_con->line_size; i++) - { - telnet_write(connection, "\b", 1); - } - } - else - { - t_con->line_size--; - t_con->line_cursor--; - /* back space: move the 'printer' head one char back, overwrite with space, move back again */ - telnet_write(connection, "\b \b", 3); - } - } - } - else if (*buf_p == 0x15) /* clear line */ - { - telnet_clear_line(connection, t_con); - } - else if (*buf_p == CTRL('B')) /* cursor left */ - { - if (t_con->line_cursor > 0) - { - telnet_write(connection, "\b", 1); - t_con->line_cursor--; - } - t_con->state = TELNET_STATE_DATA; - } - else if (*buf_p == CTRL('F')) /* cursor right */ - { - if (t_con->line_cursor < t_con->line_size) - { - telnet_write(connection, t_con->line + t_con->line_cursor++, 1); - } - t_con->state = TELNET_STATE_DATA; - } - else - { - DEBUG("unhandled nonprintable: %2.2x", *buf_p); - } - } - } - break; - case TELNET_STATE_IAC: - switch (*buf_p) - { - case '\xfe': - t_con->state = TELNET_STATE_DONT; - break; - case '\xfd': - t_con->state = TELNET_STATE_DO; - break; - case '\xfc': - t_con->state = TELNET_STATE_WONT; - break; - case '\xfb': - t_con->state = TELNET_STATE_WILL; - break; - } - break; - case TELNET_STATE_SB: - break; - case TELNET_STATE_SE: - break; - case TELNET_STATE_WILL: - case TELNET_STATE_WONT: - case TELNET_STATE_DO: - case TELNET_STATE_DONT: - t_con->state = TELNET_STATE_DATA; - break; - case TELNET_STATE_ESCAPE: - if (t_con->last_escape == '[') - { - if (*buf_p == 'D') /* cursor left */ - { - if (t_con->line_cursor > 0) - { - telnet_write(connection, "\b", 1); - t_con->line_cursor--; - } - t_con->state = TELNET_STATE_DATA; - } - else if (*buf_p == 'C') /* cursor right */ - { - if (t_con->line_cursor < t_con->line_size) - { - telnet_write(connection, t_con->line + t_con->line_cursor++, 1); - } - t_con->state = TELNET_STATE_DATA; - } - else if (*buf_p == 'A') /* cursor up */ - { - int last_history = (t_con->current_history > 0) ? t_con->current_history - 1 : TELNET_LINE_HISTORY_SIZE-1; - if (t_con->history[last_history]) - { - telnet_clear_line(connection, t_con); - t_con->line_size = strlen(t_con->history[last_history]); - t_con->line_cursor = t_con->line_size; - memcpy(t_con->line, t_con->history[last_history], t_con->line_size + 1); - telnet_write(connection, t_con->line, t_con->line_size); - t_con->current_history = last_history; - } - t_con->state = TELNET_STATE_DATA; - } - else if (*buf_p == 'B') /* cursor down */ - { - int next_history = (t_con->current_history + 1) % TELNET_LINE_HISTORY_SIZE; - if (t_con->history[next_history]) - { - telnet_clear_line(connection, t_con); - t_con->line_size = strlen(t_con->history[next_history]); - t_con->line_cursor = t_con->line_size; - memcpy(t_con->line, t_con->history[next_history], t_con->line_size + 1); - telnet_write(connection, t_con->line, t_con->line_size); - t_con->current_history = next_history; - } - t_con->state = TELNET_STATE_DATA; - } - else if (*buf_p == '3') - { - t_con->last_escape = *buf_p; - } - else - { - t_con->state = TELNET_STATE_DATA; - } - } - else if (t_con->last_escape == '3') - { - /* Remove character */ - if (*buf_p == '~') - { - if (t_con->line_cursor < t_con->line_size) - { - int i; - t_con->line_size--; - /* remove char from line buffer */ - memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor); - - /* print remainder of buffer */ - telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); - /* overwrite last char with whitespace */ - telnet_write(connection, " \b", 2); - - /* move back to cursor position*/ - for (i = t_con->line_cursor; i < t_con->line_size; i++) - { - telnet_write(connection, "\b", 1); - } - } - - t_con->state = TELNET_STATE_DATA; - } - else - { - t_con->state = TELNET_STATE_DATA; - } - } - else if (t_con->last_escape == '\x00') - { - if (*buf_p == '[') - { - t_con->last_escape = *buf_p; - } - else - { - t_con->state = TELNET_STATE_DATA; - } - } - else - { - ERROR("BUG: unexpected value in t_con->last_escape"); - t_con->state = TELNET_STATE_DATA; - } - - break; - default: - ERROR("unknown telnet state"); - exit(-1); - } - - bytes_read--; - buf_p++; - } - - return ERROR_OK; -} - -int telnet_connection_closed(connection_t *connection) -{ - telnet_connection_t *t_con = connection->priv; - int i; - - if (t_con->prompt) - { - free(t_con->prompt); - t_con->prompt = NULL; - } - - for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++) - { - if (t_con->history[i]) - { - free(t_con->history[i]); - t_con->history[i] = NULL; - } - } - - /* if this connection registered a debug-message receiver delete it */ - delete_debug_msg_receiver(connection->cmd_ctx, NULL); - - if (connection->priv) - { - free(connection->priv); - connection->priv = NULL; - } - else - { - ERROR("BUG: connection->priv == NULL"); - } - - target_unregister_event_callback(telnet_target_callback_event_handler, connection->cmd_ctx); - - return ERROR_OK; -} - -int telnet_set_prompt(connection_t *connection, char *prompt) -{ - telnet_connection_t *t_con = connection->priv; - - t_con->prompt = strdup(prompt); - - return ERROR_OK; -} - -int telnet_init(char *banner) -{ - telnet_service_t *telnet_service = malloc(sizeof(telnet_service_t)); - - if (telnet_port == 0) - { - WARNING("no telnet port specified, using default port 4444"); - telnet_port = 4444; - } - - telnet_service->banner = banner; - - add_service("telnet", CONNECTION_TELNET, telnet_port, 1, telnet_new_connection, telnet_input, telnet_connection_closed, telnet_service); - - return ERROR_OK; -} - -int telnet_register_commands(command_context_t *command_context) -{ - register_command(command_context, NULL, "exit", handle_exit_command, - COMMAND_EXEC, "exit telnet session"); - - register_command(command_context, NULL, "telnet_port", handle_telnet_port_command, - COMMAND_CONFIG, ""); - - return ERROR_OK; -} - -/* daemon configuration command telnet_port */ -int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc) -{ - if (argc == 0) - return ERROR_OK; - - /* only if the port wasn't overwritten by cmdline */ - if (telnet_port == 0) - telnet_port = strtoul(args[0], NULL, 0); - - return ERROR_OK; -} - -int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc) -{ - return ERROR_COMMAND_CLOSE_CONNECTION; -} +/*************************************************************************** + * Copyright (C) 2005 by Dominic Rath * + * Dominic.Rath@gmx.de * + * * + * Copyright (C) 2007,2008 Øyvind Harboe * + * oyvind.harboe@zylin.com * + * * + * Copyright (C) 2008 by Spencer Oliver * + * spen@spen-soft.co.uk * + * * + * This program is free software; you can redistribute it and/or modify * + * it under the terms of the GNU General Public License as published by * + * the Free Software Foundation; either version 2 of the License, or * + * (at your option) any later version. * + * * + * This program is distributed in the hope that it will be useful, * + * but WITHOUT ANY WARRANTY; without even the implied warranty of * + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * + * GNU General Public License for more details. * + * * + * You should have received a copy of the GNU General Public License * + * along with this program; if not, write to the * + * Free Software Foundation, Inc., * + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * + ***************************************************************************/ +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "telnet_server.h" +#include + +static unsigned short telnet_port = 4444; + +static char *negotiate = + "\xFF\xFB\x03" /* IAC WILL Suppress Go Ahead */ + "\xFF\xFB\x01" /* IAC WILL Echo */ + "\xFF\xFD\x03" /* IAC DO Suppress Go Ahead */ + "\xFF\xFE\x01"; /* IAC DON'T Echo */ + +#define CTRL(c) (c - '@') + +/* The only way we can detect that the socket is closed is the first time + * we write to it, we will fail. Subsequent write operations will + * succeed. Shudder! + */ +static int telnet_write(struct connection *connection, const void *data, + int len) +{ + struct telnet_connection *t_con = connection->priv; + if (t_con->closed) + return ERROR_SERVER_REMOTE_CLOSED; + + if (write_socket(connection->fd, data, len) == len) + { + return ERROR_OK; + } + t_con->closed = 1; + return ERROR_SERVER_REMOTE_CLOSED; +} + +static int telnet_prompt(struct connection *connection) +{ + struct telnet_connection *t_con = connection->priv; + + return telnet_write(connection, t_con->prompt, strlen(t_con->prompt)); +} + +static int telnet_outputline(struct connection *connection, const char *line) +{ + int len; + + /* process lines in buffer */ + while (*line) { + char *line_end = strchr(line, '\n'); + + if (line_end) + len = line_end-line; + else + len = strlen(line); + + telnet_write(connection, line, len); + if (line_end) + { + telnet_write(connection, "\r\n", 2); + line += len + 1; + } + else + { + line += len; + } + } + + return ERROR_OK; +} + +static int telnet_output(struct command_context *cmd_ctx, const char* line) +{ + struct connection *connection = cmd_ctx->output_handler_priv; + + return telnet_outputline(connection, line); +} + +static void telnet_log_callback(void *priv, const char *file, unsigned line, + const char *function, const char *string) +{ + struct connection *connection = priv; + struct telnet_connection *t_con = connection->priv; + int i; + + /* if there is no prompt, simply output the message */ + if (t_con->line_cursor < 0) + { + telnet_outputline(connection, string); + return; + } + + /* clear the command line */ + for (i = strlen(t_con->prompt) + t_con->line_size; i > 0; i -= 16) + telnet_write(connection, "\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b", i > 16 ? 16 : i); + for (i = strlen(t_con->prompt) + t_con->line_size; i > 0; i -= 16) + telnet_write(connection, " ", i > 16 ? 16 : i); + for (i = strlen(t_con->prompt) + t_con->line_size; i > 0; i -= 16) + telnet_write(connection, "\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b", i > 16 ? 16 : i); + + /* output the message */ + telnet_outputline(connection, string); + + /* put the command line to its previous state */ + telnet_prompt(connection); + telnet_write(connection, t_con->line, t_con->line_size); + for (i = t_con->line_size; i > t_con->line_cursor; i--) + telnet_write(connection, "\b", 1); +} + +static int telnet_new_connection(struct connection *connection) +{ + struct telnet_connection *telnet_connection = malloc(sizeof(struct telnet_connection)); + struct telnet_service *telnet_service = connection->service->priv; + int i; + + connection->priv = telnet_connection; + + /* initialize telnet connection information */ + telnet_connection->closed = 0; + telnet_connection->line_size = 0; + telnet_connection->line_cursor = 0; + telnet_connection->option_size = 0; + telnet_connection->prompt = strdup("> "); + telnet_connection->state = TELNET_STATE_DATA; + + /* output goes through telnet connection */ + command_set_output_handler(connection->cmd_ctx, telnet_output, connection); + + /* negotiate telnet options */ + telnet_write(connection, negotiate, strlen(negotiate)); + + /* print connection banner */ + if (telnet_service->banner) + { + telnet_write(connection, telnet_service->banner, strlen(telnet_service->banner)); + telnet_write(connection, "\r\n", 2); + } + + telnet_write(connection, "\r", 1); /* the prompt is always placed at the line beginning */ + telnet_prompt(connection); + + /* initialize history */ + for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++) + { + telnet_connection->history[i] = NULL; + } + telnet_connection->next_history = 0; + telnet_connection->current_history = 0; + + log_add_callback(telnet_log_callback, connection); + + return ERROR_OK; +} + +static void telnet_clear_line(struct connection *connection, + struct telnet_connection *t_con) +{ + /* move to end of line */ + if (t_con->line_cursor < t_con->line_size) + { + telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); + } + + /* backspace, overwrite with space, backspace */ + while (t_con->line_size > 0) + { + telnet_write(connection, "\b \b", 3); + t_con->line_size--; + } + t_con->line_cursor = 0; +} + +static int telnet_input(struct connection *connection) +{ + int bytes_read; + unsigned char buffer[TELNET_BUFFER_SIZE]; + unsigned char *buf_p; + struct telnet_connection *t_con = connection->priv; + struct command_context *command_context = connection->cmd_ctx; + + bytes_read = read_socket(connection->fd, buffer, TELNET_BUFFER_SIZE); + + if (bytes_read == 0) + return ERROR_SERVER_REMOTE_CLOSED; + else if (bytes_read == -1) + { + LOG_ERROR("error during read: %s", strerror(errno)); + return ERROR_SERVER_REMOTE_CLOSED; + } + + buf_p = buffer; + while (bytes_read) + { + switch (t_con->state) + { + case TELNET_STATE_DATA: + if (*buf_p == 0xff) + { + t_con->state = TELNET_STATE_IAC; + } + else + { + if (isprint(*buf_p)) /* printable character */ + { + /* watch buffer size leaving one spare character for string null termination */ + if (t_con->line_size == TELNET_LINE_MAX_SIZE-1) + { + /* output audible bell if buffer is full */ + telnet_write(connection, "\x07", 1); /* "\a" does not work, at least on windows */ + } + else if (t_con->line_cursor == t_con->line_size) + { + telnet_write(connection, buf_p, 1); + t_con->line[t_con->line_size++] = *buf_p; + t_con->line_cursor++; + } + else + { + int i; + memmove(t_con->line + t_con->line_cursor + 1, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); + t_con->line[t_con->line_cursor] = *buf_p; + t_con->line_size++; + telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); + t_con->line_cursor++; + for (i = t_con->line_cursor; i < t_con->line_size; i++) + { + telnet_write(connection, "\b", 1); + } + } + } + else /* non-printable */ + { + if (*buf_p == 0x1b) /* escape */ + { + t_con->state = TELNET_STATE_ESCAPE; + t_con->last_escape = '\x00'; + } + else if ((*buf_p == 0xd) || (*buf_p == 0xa)) /* CR/LF */ + { + int retval; + + /* skip over combinations with CR/LF and NUL characters */ + if ((bytes_read > 1) && ((*(buf_p + 1) == 0xa) || (*(buf_p + 1) == 0xd))) + { + buf_p++; + bytes_read--; + } + if ((bytes_read > 1) && (*(buf_p + 1) == 0)) + { + buf_p++; + bytes_read--; + } + t_con->line[t_con->line_size] = 0; + + telnet_write(connection, "\r\n\x00", 3); + + if (strcmp(t_con->line, "history") == 0) + { + int i; + for (i = 1; i < TELNET_LINE_HISTORY_SIZE; i++) + { + /* the t_con->next_history line contains empty string (unless NULL), thus it is not printed */ + char *history_line = t_con->history[(t_con->next_history + i) % TELNET_LINE_HISTORY_SIZE]; + if (history_line) + { + telnet_write(connection, history_line, strlen(history_line)); + telnet_write(connection, "\r\n\x00", 3); + } + } + t_con->line_size = 0; + t_con->line_cursor = 0; + continue; + } + + /* save only non-blank not repeating lines in the history */ + char *prev_line = t_con->history[(t_con->current_history > 0) ? t_con->current_history - 1 : TELNET_LINE_HISTORY_SIZE-1]; + if (*t_con->line && (prev_line == NULL || strcmp(t_con->line, prev_line))) + { + /* if the history slot is already taken, free it */ + if (t_con->history[t_con->next_history]) + { + free(t_con->history[t_con->next_history]); + } + + /* add line to history */ + t_con->history[t_con->next_history] = strdup(t_con->line); + + /* wrap history at TELNET_LINE_HISTORY_SIZE */ + t_con->next_history = (t_con->next_history + 1) % TELNET_LINE_HISTORY_SIZE; + + /* current history line starts at the new entry */ + t_con->current_history = t_con->next_history; + + if (t_con->history[t_con->current_history]) + { + free(t_con->history[t_con->current_history]); + } + t_con->history[t_con->current_history] = strdup(""); + } + + t_con->line_size = 0; + + t_con->line_cursor = -1; /* to supress prompt in log callback during command execution */ + + retval = command_run_line(command_context, t_con->line); + + t_con->line_cursor = 0; + + if (retval == ERROR_COMMAND_CLOSE_CONNECTION) + return ERROR_SERVER_REMOTE_CLOSED; + + telnet_write(connection, "\r", 1); /* the prompt is always placed at the line beginning */ + retval = telnet_prompt(connection); + if (retval == ERROR_SERVER_REMOTE_CLOSED) + return ERROR_SERVER_REMOTE_CLOSED; + + } + else if ((*buf_p == 0x7f) || (*buf_p == 0x8)) /* delete character */ + { + if (t_con->line_cursor > 0) + { + if (t_con->line_cursor != t_con->line_size) + { + int i; + telnet_write(connection, "\b", 1); + t_con->line_cursor--; + t_con->line_size--; + memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor); + + telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); + telnet_write(connection, " \b", 2); + for (i = t_con->line_cursor; i < t_con->line_size; i++) + { + telnet_write(connection, "\b", 1); + } + } + else + { + t_con->line_size--; + t_con->line_cursor--; + /* back space: move the 'printer' head one char back, overwrite with space, move back again */ + telnet_write(connection, "\b \b", 3); + } + } + } + else if (*buf_p == 0x15) /* clear line */ + { + telnet_clear_line(connection, t_con); + } + else if (*buf_p == CTRL('B')) /* cursor left */ + { + if (t_con->line_cursor > 0) + { + telnet_write(connection, "\b", 1); + t_con->line_cursor--; + } + t_con->state = TELNET_STATE_DATA; + } + else if (*buf_p == CTRL('F')) /* cursor right */ + { + if (t_con->line_cursor < t_con->line_size) + { + telnet_write(connection, t_con->line + t_con->line_cursor++, 1); + } + t_con->state = TELNET_STATE_DATA; + } + else + { + LOG_DEBUG("unhandled nonprintable: %2.2x", *buf_p); + } + } + } + break; + case TELNET_STATE_IAC: + switch (*buf_p) + { + case 0xfe: + t_con->state = TELNET_STATE_DONT; + break; + case 0xfd: + t_con->state = TELNET_STATE_DO; + break; + case 0xfc: + t_con->state = TELNET_STATE_WONT; + break; + case 0xfb: + t_con->state = TELNET_STATE_WILL; + break; + } + break; + case TELNET_STATE_SB: + break; + case TELNET_STATE_SE: + break; + case TELNET_STATE_WILL: + case TELNET_STATE_WONT: + case TELNET_STATE_DO: + case TELNET_STATE_DONT: + t_con->state = TELNET_STATE_DATA; + break; + case TELNET_STATE_ESCAPE: + if (t_con->last_escape == '[') + { + if (*buf_p == 'D') /* cursor left */ + { + if (t_con->line_cursor > 0) + { + telnet_write(connection, "\b", 1); + t_con->line_cursor--; + } + t_con->state = TELNET_STATE_DATA; + } + else if (*buf_p == 'C') /* cursor right */ + { + if (t_con->line_cursor < t_con->line_size) + { + telnet_write(connection, t_con->line + t_con->line_cursor++, 1); + } + t_con->state = TELNET_STATE_DATA; + } + else if (*buf_p == 'A') /* cursor up */ + { + int last_history = (t_con->current_history > 0) ? t_con->current_history - 1 : TELNET_LINE_HISTORY_SIZE-1; + if (t_con->history[last_history]) + { + telnet_clear_line(connection, t_con); + t_con->line_size = strlen(t_con->history[last_history]); + t_con->line_cursor = t_con->line_size; + memcpy(t_con->line, t_con->history[last_history], t_con->line_size); + telnet_write(connection, t_con->line, t_con->line_size); + t_con->current_history = last_history; + } + t_con->state = TELNET_STATE_DATA; + } + else if (*buf_p == 'B') /* cursor down */ + { + int next_history = (t_con->current_history + 1) % TELNET_LINE_HISTORY_SIZE; + if (t_con->history[next_history]) + { + telnet_clear_line(connection, t_con); + t_con->line_size = strlen(t_con->history[next_history]); + t_con->line_cursor = t_con->line_size; + memcpy(t_con->line, t_con->history[next_history], t_con->line_size); + telnet_write(connection, t_con->line, t_con->line_size); + t_con->current_history = next_history; + } + t_con->state = TELNET_STATE_DATA; + } + else if (*buf_p == '3') + { + t_con->last_escape = *buf_p; + } + else + { + t_con->state = TELNET_STATE_DATA; + } + } + else if (t_con->last_escape == '3') + { + /* Remove character */ + if (*buf_p == '~') + { + if (t_con->line_cursor < t_con->line_size) + { + int i; + t_con->line_size--; + /* remove char from line buffer */ + memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor); + + /* print remainder of buffer */ + telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor); + /* overwrite last char with whitespace */ + telnet_write(connection, " \b", 2); + + /* move back to cursor position*/ + for (i = t_con->line_cursor; i < t_con->line_size; i++) + { + telnet_write(connection, "\b", 1); + } + } + + t_con->state = TELNET_STATE_DATA; + } + else + { + t_con->state = TELNET_STATE_DATA; + } + } + else if (t_con->last_escape == '\x00') + { + if (*buf_p == '[') + { + t_con->last_escape = *buf_p; + } + else + { + t_con->state = TELNET_STATE_DATA; + } + } + else + { + LOG_ERROR("BUG: unexpected value in t_con->last_escape"); + t_con->state = TELNET_STATE_DATA; + } + + break; + default: + LOG_ERROR("unknown telnet state"); + exit(-1); + } + + bytes_read--; + buf_p++; + } + + return ERROR_OK; +} + +static int telnet_connection_closed(struct connection *connection) +{ + struct telnet_connection *t_con = connection->priv; + int i; + + log_remove_callback(telnet_log_callback, connection); + + if (t_con->prompt) + { + free(t_con->prompt); + t_con->prompt = NULL; + } + + for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++) + { + if (t_con->history[i]) + { + free(t_con->history[i]); + t_con->history[i] = NULL; + } + } + + /* if this connection registered a debug-message receiver delete it */ + delete_debug_msg_receiver(connection->cmd_ctx, NULL); + + if (connection->priv) + { + free(connection->priv); + connection->priv = NULL; + } + else + { + LOG_ERROR("BUG: connection->priv == NULL"); + } + + return ERROR_OK; +} + +int telnet_init(char *banner) +{ + struct telnet_service *telnet_service = malloc(sizeof(struct telnet_service)); + + if (telnet_port == 0) + { + LOG_INFO("telnet port disabled"); + free(telnet_service); + return ERROR_OK; + } + + telnet_service->banner = banner; + + add_service("telnet", CONNECTION_TCP, telnet_port, 1, telnet_new_connection, telnet_input, telnet_connection_closed, telnet_service); + + return ERROR_OK; +} + +/* daemon configuration command telnet_port */ +COMMAND_HANDLER(handle_telnet_port_command) +{ + return CALL_COMMAND_HANDLER(server_port_command, &telnet_port); +} + +COMMAND_HANDLER(handle_exit_command) +{ + return ERROR_COMMAND_CLOSE_CONNECTION; +} + +static const struct command_registration telnet_command_handlers[] = { + { + .name = "exit", + .handler = handle_exit_command, + .mode = COMMAND_EXEC, + .help = "exit telnet session", + }, + { + .name = "telnet_port", + .handler = handle_telnet_port_command, + .mode = COMMAND_ANY, + .help = "Specify port on which to listen " + "for incoming telnet connections. " + "No arguments reports telnet port; zero disables.", + .usage = "[port_num]", + }, + COMMAND_REGISTRATION_DONE +}; + +int telnet_register_commands(struct command_context *cmd_ctx) +{ + return register_commands(cmd_ctx, NULL, telnet_command_handlers); +}