vty.c

大名鼎鼎的路由器源码。程序分ZEBRA、OSPFRIP等3个包。程序框架采用一个路由协议一个进程的方式

/*
 * Virtual terminal [aka TeletYpe] interface routine.
 * Copyright (C) 1997, 98 Kunihiro Ishiguro
 *
 * This file is part of GNU Zebra.
 *
 * GNU Zebra 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, or (at your option) any
 * later version.
 *
 * GNU Zebra 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 GNU Zebra; see the file COPYING.  If not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.  
 */

#include <zebra.h>

#include "linklist.h"
#include "buffer.h"
#include "version.h"
#include "command.h"
#include "sockunion.h"
#include "thread.h"
#include "memory.h"
#include "str.h"
#include "log.h"
#include "prefix.h"
#include "filter.h"

/* Vty events */
enum event 
  {
    VTY_SERV,
    VTY_READ,
    VTY_WRITE,
    VTY_TIMEOUT_RESET,
#ifdef VTYSH
    VTYSH_SERV,
    VTYSH_READ
#endif /* VTYSH */
  };

static void vty_event (enum event, int, struct vty *);

/* Extern host structure from command.c */
extern struct host host;

/* Vector which store each vty structure. */
static vector vtyvec;

/* Vty timeout value. */
static unsigned long vty_timeout_val = VTY_TIMEOUT_DEFAULT;

/* Vty access-class command */
static char *vty_accesslist_name = NULL;

/* Vty access-calss for IPv6. */
static char *vty_ipv6_accesslist_name = NULL;

/* VTY server thread. */
vector Vvty_serv_thread;

/* Current directory. */
char *vty_cwd = NULL;

/* Configure lock. */
static int vty_config;

/* Login password check. */
static int no_password_check = 0;

/* Integrated configuration file path */
char integrate_default[] = SYSCONFDIR INTEGRATE_DEFAULT_CONFIG;


/* VTY standard output function. */
int
vty_out (struct vty *vty, const char *format, ...)
{
  va_list args;
  int len = 0;
  int size = 1024;
  char buf[1024];
  char *p = NULL;
  
  va_start (args, format);

  if (vty_shell (vty))
    vprintf (format, args);
  else
    {
      /* Try to write to initial buffer.  */
      len = vsnprintf (buf, sizeof buf, format, args);

      /* Initial buffer is not enough.  */
      if (len < 0 || len >= size)
	{
	  while (1)
	    {
	      if (len > -1)
		size = len + 1;
	      else
		size = size * 2;

	      p = XREALLOC (MTYPE_VTY_OUT_BUF, p, size);
	      if (! p)
		return -1;

	      len = vsnprintf (p, size, format, args);

	      if (len > -1 && len < size)
		break;
	    }
	}

      /* When initial buffer is enough to store all output.  */
      if (! p)
	p = buf;

      /* Pointer p must point out buffer. */
      if (vty_shell_serv (vty))
	write (vty->fd, (u_char *) p, len);
      else
	buffer_write (vty->obuf, (u_char *) p, len);

      /* If p is not different with buf, it is allocated buffer.  */
      if (p != buf)
	XFREE (MTYPE_VTY_OUT_BUF, p);
    }

  va_end (args);

  return len;
}

#define TIME_BUF 27

/* current time string. */
int
time_str (char *buf)
{
  time_t clock;
  struct tm *tm;
  int ret;

  time (&clock);
  tm = localtime (&clock);

  ret = strftime (buf, TIME_BUF, "%Y/%m/%d %H:%M:%S", tm);

  return ret;
}

int
vty_log_out (struct vty *vty, const char *proto_str, const char *format,
	     va_list va)
{
  int len;
  int ret;
  char buf[1024];
  char time_buf[TIME_BUF];

  ret = time_str (time_buf);

  if (ret != 0)
    {
      snprintf (buf, sizeof buf, "%s ", time_buf);
      write (vty->fd, buf, strlen (time_buf) + 1);
    }

  snprintf (buf, sizeof buf, "%s: ", proto_str);
  write (vty->fd, buf, strlen (proto_str) + 2);

  len = vsnprintf (buf, sizeof buf, format, va);
  if (len < 0)
    return -1;
  write (vty->fd, (u_char *)buf, len);

  snprintf (buf, sizeof buf, "\r\n");
  write (vty->fd, buf, 2);

  return len;
}

/* Output current time to the vty. */
void
vty_time_print (struct vty *vty, int cr)
{
  int ret;
  char buf [TIME_BUF];
 
  ret = time_str (buf);

  if (ret == 0)
    {
      zlog (NULL, LOG_INFO, "strftime error");
      return;
    }

  if (cr)
    vty_out (vty, "%s\n", buf);
  else
    vty_out (vty, "%s ", buf);

  return;
}

/* Say hello to vty interface. */
void
vty_hello (struct vty *vty)
{
  if (host.motd)
    vty_out (vty, host.motd);
}

/* Put out prompt and wait input from user. */
static void
vty_prompt (struct vty *vty)
{
  struct utsname names;
  const char*hostname;

  if (vty->type == VTY_TERM)
    {
      hostname = host.name;
      if (!hostname)
	{
	  uname (&names);
	  hostname = names.nodename;
	}
      vty_out (vty, cmd_prompt (vty->node), hostname);
    }
}

/* Send WILL TELOPT_ECHO to remote server. */
void
vty_will_echo (struct vty *vty)
{
  char cmd[] = { IAC, WILL, TELOPT_ECHO, '\0' };
  vty_out (vty, "%s", cmd);
}

/* Make suppress Go-Ahead telnet option. */
static void
vty_will_suppress_go_ahead (struct vty *vty)
{
  char cmd[] = { IAC, WILL, TELOPT_SGA, '\0' };
  vty_out (vty, "%s", cmd);
}

/* Make don't use linemode over telnet. */
static void
vty_dont_linemode (struct vty *vty)
{
  char cmd[] = { IAC, DONT, TELOPT_LINEMODE, '\0' };
  vty_out (vty, "%s", cmd);
}

/* Use window size. */
static void
vty_do_window_size (struct vty *vty)
{
  char cmd[] = { IAC, DO, TELOPT_NAWS, '\0' };
  vty_out (vty, "%s", cmd);
}

#if 0 /* Currently not used. */
/* Make don't use lflow vty interface. */
static void
vty_dont_lflow_ahead (struct vty *vty)
{
  char cmd[] = { IAC, DONT, TELOPT_LFLOW, '\0' };
  vty_out (vty, "%s", cmd);
}
#endif /* 0 */

/* Allocate new vty struct. */
struct vty *
vty_new ()
{
  struct vty *new = XCALLOC (MTYPE_VTY, sizeof (struct vty));

  new->obuf = (struct buffer *) buffer_new (100);
  new->buf = XCALLOC (MTYPE_VTY, VTY_BUFSIZ);
  new->max = VTY_BUFSIZ;
  new->sb_buffer = NULL;

  return new;
}

/* Authentication of vty */
static void
vty_auth (struct vty *vty, char *buf)
{
  char *passwd = NULL;
  enum node_type next_node = 0;
  int fail;
  char *crypt (const char *, const char *);

  switch (vty->node)
    {
    case AUTH_NODE:
      if (host.encrypt)
	passwd = host.password_encrypt;
      else
	passwd = host.password;
      if (host.advanced)
	next_node = host.enable ? VIEW_NODE : ENABLE_NODE;
      else
	next_node = VIEW_NODE;
      break;
    case AUTH_ENABLE_NODE:
      if (host.encrypt)
	passwd = host.enable_encrypt;
      else
	passwd = host.enable;
      next_node = ENABLE_NODE;
      break;
    }

  if (passwd)
    {
      if (host.encrypt)
	fail = strcmp (crypt(buf, passwd), passwd);
      else
	fail = strcmp (buf, passwd);
    }
  else
    fail = 1;

  if (! fail)
    {
      vty->fail = 0;
      vty->node = next_node;	/* Success ! */
    }
  else
    {
      vty->fail++;
      if (vty->fail >= 3)
	{
	  if (vty->node == AUTH_NODE)
	    {
	      vty_out (vty, "%% Bad passwords, too many failures!%s", VTY_NEWLINE);
	      vty->status = VTY_CLOSE;
	    }
	  else			
	    {
	      /* AUTH_ENABLE_NODE */
	      vty->fail = 0;
	      vty_out (vty, "%% Bad enable passwords, too many failures!%s", VTY_NEWLINE);
	      vty->node = VIEW_NODE;
	    }
	}
    }
}

/* Command execution over the vty interface. */
int
vty_command (struct vty *vty, char *buf)
{
  int ret;
  vector vline;

  /* Split readline string up into the vector */
  vline = cmd_make_strvec (buf);

  if (vline == NULL)
    return CMD_SUCCESS;

  ret = cmd_execute_command (vline, vty, NULL);

  if (ret != CMD_SUCCESS)
    switch (ret)
      {
      case CMD_WARNING:
	if (vty->type == VTY_FILE)
	  vty_out (vty, "Warning...%s", VTY_NEWLINE);
	break;
      case CMD_ERR_AMBIGUOUS:
	vty_out (vty, "%% Ambiguous command.%s", VTY_NEWLINE);
	break;
      case CMD_ERR_NO_MATCH:
	vty_out (vty, "%% Unknown command.%s", VTY_NEWLINE);
	break;
      case CMD_ERR_INCOMPLETE:
	vty_out (vty, "%% Command incomplete.%s", VTY_NEWLINE);
	break;
      }
  cmd_free_strvec (vline);

  return ret;
}

char telnet_backward_char = 0x08;
char telnet_space_char = ' ';

/* Basic function to write buffer to vty. */
static void
vty_write (struct vty *vty, char *buf, size_t nbytes)
{
  if ((vty->node == AUTH_NODE) || (vty->node == AUTH_ENABLE_NODE))
    return;

  /* Should we do buffering here ?  And make vty_flush (vty) ? */
  buffer_write (vty->obuf, (u_char *)buf, nbytes);
}

/* Ensure length of input buffer.  Is buffer is short, double it. */
static void
vty_ensure (struct vty *vty, int length)
{
  if (vty->max <= length)
    {
      vty->max *= 2;
      vty->buf = XREALLOC (MTYPE_VTY, vty->buf, vty->max);
    }
}

/* Basic function to insert character into vty. */
static void
vty_self_insert (struct vty *vty, char c)
{
  int i;
  int length;

  vty_ensure (vty, vty->length + 1);
  length = vty->length - vty->cp;
  memmove (&vty->buf[vty->cp + 1], &vty->buf[vty->cp], length);
  vty->buf[vty->cp] = c;

  vty_write (vty, &vty->buf[vty->cp], length + 1);
  for (i = 0; i < length; i++)
    vty_write (vty, &telnet_backward_char, 1);

  vty->cp++;
  vty->length++;
}

/* Self insert character 'c' in overwrite mode. */
static void
vty_self_insert_overwrite (struct vty *vty, char c)
{
  vty_ensure (vty, vty->length + 1);
  vty->buf[vty->cp++] = c;

  if (vty->cp > vty->length)
    vty->length++;

  if ((vty->node == AUTH_NODE) || (vty->node == AUTH_ENABLE_NODE))
    return;

  vty_write (vty, &c, 1);
}

/* Insert a word into vty interface with overwrite mode. */
static void
vty_insert_word_overwrite (struct vty *vty, char *str)
{
  int len = strlen (str);
  vty_write (vty, str, len);
  strcpy (&vty->buf[vty->cp], str);
  vty->cp += len;
  vty->length = vty->cp;
}

/* Forward character. */
static void
vty_forward_char (struct vty *vty)
{
  if (vty->cp < vty->length)
    {
      vty_write (vty, &vty->buf[vty->cp], 1);
      vty->cp++;
    }
}

/* Backward character. */
static void
vty_backward_char (struct vty *vty)
{
  if (vty->cp > 0)
    {
      vty->cp--;
      vty_write (vty, &telnet_backward_char, 1);
    }
}

/* Move to the beginning of the line. */
static void
vty_beginning_of_line (struct vty *vty)
{
  while (vty->cp)
    vty_backward_char (vty);
}

/* Move to the end of the line. */
static void
vty_end_of_line (struct vty *vty)
{
  while (vty->cp < vty->length)
    vty_forward_char (vty);
}

static void vty_kill_line_from_beginning (struct vty *);
static void vty_redraw_line (struct vty *);

/* Print command line history.  This function is called from
   vty_next_line and vty_previous_line. */
static void
vty_history_print (struct vty *vty)
{
  int length;

  vty_kill_line_from_beginning (vty);

  /* Get previous line from history buffer */
  length = strlen (vty->hist[vty->hp]);
  memcpy (vty->buf, vty->hist[vty->hp], length);
  vty->cp = vty->length = length;

  /* Redraw current line */
  vty_redraw_line (vty);
}

/* Show next command line history. */
void
vty_next_line (struct vty *vty)
{
  int try_index;

  if (vty->hp == vty->hindex)
    return;

  /* Try is there history exist or not. */
  try_index = vty->hp;
  if (try_index == (VTY_MAXHIST - 1))
    try_index = 0;
  else
    try_index++;

  /* If there is not history return. */
  if (vty->hist[try_index] == NULL)
    return;
  else
    vty->hp = try_index;

  vty_history_print (vty);
}

/* Show previous command line history. */
void
vty_previous_line (struct vty *vty)
{
  int try_index;

  try_index = vty->hp;
  if (try_index == 0)
    try_index = VTY_MAXHIST - 1;
  else
    try_index--;

  if (vty->hist[try_index] == NULL)
    return;
  else
    vty->hp = try_index;

  vty_history_print (vty);
}

/* This function redraw all of the command line character. */
static void
vty_redraw_line (struct vty *vty)
{
  vty_write (vty, vty->buf, vty->length);
  vty->cp = vty->length;
}

/* Forward word. */
static void
vty_forward_word (struct vty *vty)
{
  while (vty->cp != vty->length && vty->buf[vty->cp] != ' ')
    vty_forward_char (vty);
  
  while (vty->cp != vty->length && vty->buf[vty->cp] == ' ')
    vty_forward_char (vty);
}

/* Backward word without skipping training space. */
static void
vty_backward_pure_word (struct vty *vty)
{
  while (vty->cp > 0 && vty->buf[vty->cp - 1] != ' ')
    vty_backward_char (vty);
}

/* Backward word. */
static void
vty_backward_word (struct vty *vty)
{
  while (vty->cp > 0 && vty->buf[vty->cp - 1] == ' ')
    vty_backward_char (vty);

  while (vty->cp > 0 && vty->buf[vty->cp - 1] != ' ')
    vty_backward_char (vty);
}

/* When '^D' is typed at the beginning of the line we move to the down
   level. */
static void
vty_down_level (struct vty *vty)
{
  vty_out (vty, "%s", VTY_NEWLINE);
  config_exit (NULL, vty, 0, NULL);
  vty_prompt (vty);
  vty->cp = 0;
}

/* When '^Z' is received from vty, move down to the enable mode. */
void
vty_end_config (struct vty *vty)
{
  vty_out (vty, "%s", VTY_NEWLINE);

  switch (vty->node)
    {
    case VIEW_NODE:
    case ENABLE_NODE:
      /* Nothing to do. */
      break;
    case CONFIG_NODE:
    case INTERFACE_NODE:
    case ZEBRA_NODE:
    case RIP_NODE:
    case RIPNG_NODE:
    case BGP_NODE:
    case BGP_VPNV4_NODE:
    case BGP_IPV4_NODE:
    case BGP_IPV4M_NODE:
    case BGP_IPV6_NODE:
    case RMAP_NODE:
    case OSPF_NODE:
    case OSPF6_NODE:
    case KEYCHAIN_NODE:
    case KEYCHAIN_KEY_NODE:
    case MASC_NODE:
    case VTY_NODE:
      vty_config_unlock (vty);
      vty->node = ENABLE_NODE;
      break;
    default:
      /* Unknown node, we have to ignore it. */
      break;
    }

  vty_prompt (vty);
  vty->cp = 0;
}

/* Delete a charcter at the current point. */
static void
vty_delete_char (struct vty *vty)
{
  int i;
  int size;

  if (vty->node == AUTH_NODE || vty->node == AUTH_ENABLE_NODE)
    return;

  if (vty->length == 0)
    {
      vty_down_level (vty);
      return;
    }

  if (vty->cp == vty->length)
    return;			/* completion need here? */

  size = vty->length - vty->cp;

  vty->length--;
  memmove (&vty->buf[vty->cp], &vty->buf[vty->cp + 1], size - 1);
  vty->buf[vty->length] = '\0';

  vty_write (vty, &vty->buf[vty->cp], size - 1);
  vty_write (vty, &telnet_space_char, 1);

  for (i = 0; i < size; i++)
    vty_write (vty, &telnet_backward_char, 1);
}

/* Delete a character before the point. */
static void
vty_delete_backward_char (struct vty *vty)
{
  if (vty->cp == 0)
    return;