* 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 *
#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 <stdlib.h>
-#include <unistd.h>
-#include <errno.h>
-#include <string.h>
-#include <ctype.h>
-
-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 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!
*/
-int telnet_write(connection_t *connection, const void *data, int len)
+int telnet_write(struct connection *connection, const void *data, int len)
{
- telnet_connection_t *t_con = connection->priv;
+ struct telnet_connection *t_con = connection->priv;
if (t_con->closed)
return ERROR_SERVER_REMOTE_CLOSED;
return ERROR_SERVER_REMOTE_CLOSED;
}
-int telnet_prompt(connection_t *connection)
+int telnet_prompt(struct connection *connection)
{
- telnet_connection_t *t_con = connection->priv;
+ struct telnet_connection *t_con = connection->priv;
+ telnet_write(connection, "\r", 1); /* the prompt is always placed at the line beginning */
return telnet_write(connection, t_con->prompt, strlen(t_con->prompt));
}
-int telnet_outputline(connection_t *connection, const char *line)
+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
telnet_write(connection, line, len);
if (line_end)
{
- telnet_write(connection, "\r\n\0", 3);
- line += len+1;
+ telnet_write(connection, "\r\n", 2);
+ line += len + 1;
}
else
{
line += len;
}
}
-
+
return ERROR_OK;
}
-int telnet_output(struct command_context_s *cmd_ctx, char* line)
+int telnet_output(struct command_context *cmd_ctx, const char* line)
{
- connection_t *connection = cmd_ctx->output_handler_priv;
-
+ struct connection *connection = cmd_ctx->output_handler_priv;
+
return telnet_outputline(connection, line);
}
-void telnet_log_callback(void *priv, const char *file, int line,
+void telnet_log_callback(void *priv, const char *file, unsigned line,
const char *function, const char *string)
{
- connection_t *connection = priv;
- telnet_outputline(connection, string);
-}
+ struct connection *connection = priv;
+ struct telnet_connection *t_con = connection->priv;
+ int i;
-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)
+ /* if there is no prompt, simply output the message */
+ if (t_con->line_cursor < 0)
{
- 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;
+ telnet_outputline(connection, string);
+ return;
}
- return ERROR_OK;
+ /* clear the command line */
+ telnet_write(connection, "\r", 1);
+ for (i = strlen(t_con->prompt) + t_con->line_size; i > 0; i -= 16)
+ telnet_write(connection, " ", i > 16 ? 16 : i);
+ telnet_write(connection, "\r", 1);
+
+ /* 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);
}
-int telnet_new_connection(connection_t *connection)
+int telnet_new_connection(struct connection *connection)
{
- telnet_connection_t *telnet_connection = malloc(sizeof(telnet_connection_t));
- telnet_service_t *telnet_service = connection->service->priv;
+ 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->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_write(connection, "\r\n", 2);
}
-
+
telnet_prompt(connection);
-
+
/* initialize history */
for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
{
telnet_connection->next_history = 0;
telnet_connection->current_history = 0;
- target_register_event_callback(telnet_target_callback_event_handler, connection->cmd_ctx);
-
+ log_add_callback(telnet_log_callback, connection);
+
return ERROR_OK;
}
-void telnet_clear_line(connection_t *connection, telnet_connection_t *t_con)
+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)
t_con->line_cursor = 0;
}
-int telnet_input(connection_t *connection)
+int telnet_input(struct connection *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;
-
+ 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)
{
- ERROR("error during read: %s", strerror(errno));
+ LOG_ERROR("error during read: %s", strerror(errno));
return ERROR_SERVER_REMOTE_CLOSED;
}
-
+
buf_p = buffer;
while (bytes_read)
{
{
if (isprint(*buf_p)) /* printable character */
{
- telnet_write(connection, buf_p, 1);
- if (t_con->line_cursor == t_con->line_size)
+ /* 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++;
}
{
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[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 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))
+
+ /* 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 ((*(buf_p + 1) == 0) && (bytes_read > 1))
+ 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 = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
+ for (i = 1; i < TELNET_LINE_HISTORY_SIZE; i++)
{
- if (t_con->history[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, t_con->history[i], strlen(t_con->history[i]));
+ telnet_write(connection, history_line, strlen(history_line));
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)
+ /* 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("");
}
-
- int t = telnet_prompt(connection);
- if (t == ERROR_SERVER_REMOTE_CLOSED)
- return t;
-
+
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;
+
+ 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 */
{
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++)
}
else
{
- DEBUG("unhandled nonprintable: %2.2x", *buf_p);
+ LOG_DEBUG("unhandled nonprintable: %2.2x", *buf_p);
}
}
}
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);
+ 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;
}
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);
+ 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->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
}
else
{
- ERROR("BUG: unexpected value in t_con->last_escape");
+ LOG_ERROR("BUG: unexpected value in t_con->last_escape");
t_con->state = TELNET_STATE_DATA;
}
-
+
break;
default:
- ERROR("unknown telnet state");
+ LOG_ERROR("unknown telnet state");
exit(-1);
}
bytes_read--;
buf_p++;
}
-
+
return ERROR_OK;
}
-int telnet_connection_closed(connection_t *connection)
+int telnet_connection_closed(struct connection *connection)
{
- telnet_connection_t *t_con = connection->priv;
+ 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])
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);
}
else
{
- ERROR("BUG: connection->priv == NULL");
+ LOG_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)
+int telnet_set_prompt(struct connection *connection, char *prompt)
{
- telnet_connection_t *t_con = connection->priv;
+ struct telnet_connection *t_con = connection->priv;
+
+ if (t_con->prompt != NULL)
+ free(t_con->prompt);
t_con->prompt = strdup(prompt);
-
+
return ERROR_OK;
}
int telnet_init(char *banner)
{
- telnet_service_t *telnet_service = malloc(sizeof(telnet_service_t));
-
+ struct telnet_service *telnet_service = malloc(sizeof(struct telnet_service));
+
if (telnet_port == 0)
{
- WARNING("no telnet port specified, using default port 4444");
- telnet_port = 4444;
+ LOG_INFO("telnet port disabled");
+ free(telnet_service);
+ return ERROR_OK;
}
-
+
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, "");
-
+ 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 */
-int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+COMMAND_HANDLER(handle_telnet_port_command)
{
- 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;
+ return CALL_COMMAND_HANDLER(server_port_command, &telnet_port);
}
-int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+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 = "port on which to listen "
+ "for incoming telnet connections",
+ .usage = "<port>",
+ },
+ COMMAND_REGISTRATION_DONE
+};
+
+int telnet_register_commands(struct command_context *cmd_ctx)
+{
+ return register_commands(cmd_ctx, NULL, telnet_command_handlers);
+}