clixon/apps/netconf/netconf_lib.c

/*
 *
  Copyright (C) 2009-2016 Olof Hagsand and Benny Holmgren

  This file is part of CLICON.

  CLICON 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 3 of the License, or
  (at your option) any later version.

  CLICON 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 CLICON; see the file COPYING.  If not, see
  <http://www.gnu.org/licenses/>.

 *
 *  netconf lib
 *****************************************************************************/
#ifdef HAVE_CONFIG_H
#include "clicon_config.h" /* generated by config & autoconf */
#endif

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <signal.h>
#include <fcntl.h>
#include <time.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <syslog.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/param.h>
#include <assert.h>

/* cligen */
#include <cligen/cligen.h>

/* clicon */
#include <clicon/clicon.h>

#include "netconf_rpc.h"
#include "netconf_lib.h"

/*
 * Exported variables
 */
enum transport_type    transport = NETCONF_SSH; 
int cc_closed = 0;

static int cc_ok = 0;

void
netconf_ok_set(int ok)
{
    cc_ok = ok;
}

int
netconf_ok_get(void)
{
    return cc_ok;
}

int
add_preamble(cbuf *xf)
{
    if (transport == NETCONF_SOAP)
	cprintf(xf, "\n<soapenv:Envelope\n xmlns:soapenv=\"http://www.w3.org/2003/05/soap-envelope\">\n"
	"<soapenv:Body>");
    return 0;
}

/* 
 * add_postamble
 * add netconf xml postamble of message. That is, xml after the body of the message.
 * for soap this is the envelope stuff, for ssh this is ]]>]]>
 */
int
add_postamble(cbuf *xf)
{
    switch (transport){
    case NETCONF_SSH:
	cprintf(xf, "]]>]]>");     /* Add RFC4742 end-of-message marker */
	break;
    case NETCONF_SOAP:
	cprintf(xf, "\n</soapenv:Body>" "</soapenv:Envelope>");
	break;
    }
    return 0;
}

/* 
 * add_error_preamble
 * compared to regular messages (see add_preamble), error message differ in some
 * protocols (eg soap) by adding a longer and deeper header.
 */
int
add_error_preamble(cbuf *xf, char *reason)
{
    switch (transport){
    case NETCONF_SOAP:
	cprintf(xf, "<soapenv:Envelope xmlns:soapenv=\"http://www.w3.org/2003/05/soap-envelope\" xmlns:xml=\"http://www.w3.org/XML/1998/namespace\">"
		"<soapenv:Body>"
		"<soapenv:Fault>"
		"<soapenv:Code>"
		"<soapenv:Value>env:Receiver</soapenv:Value>"
		"</soapenv:Code>"
		"<soapenv:Reason>"
		"<soapenv:Text xml:lang=\"en\">%s</soapenv:Text>"
		"</soapenv:Reason>"
		"<detail>", reason);
	break;
    default:
	if (add_preamble(xf) < 0)
	    return -1;
	break;
    }
    return 0;
}

/* 
 * add_error_postamble
 * compared to regular messages (see add_postamble), error message differ in some
 * protocols (eg soap) by adding a longer and deeper header.
 */
int
add_error_postamble(cbuf *xf)
{
    switch (transport){
    case NETCONF_SOAP:
	cprintf(xf, "</detail>" "</soapenv:Fault>");
    default: /* fall through */
	if (add_postamble(xf) < 0)
	    return -1;
	break;
    }
    return 0;
}

/*! Look for a text pattern in an input string, one char at a time
 *  @param[in]     tag     What to look for
 *  @param[in]     ch      New input character
 *  @param[in,out] state   A state integer holding how far we have parsed.
 *  @retval        0       No, we havent detected end tag
 *  @retval        1       Yes, we have detected end tag!
 * XXX: move to clicon_xml?
 */
int
detect_endtag(char *tag, char ch, int *state)
{
    int retval = 0;

    if (tag[*state] == ch){
	(*state)++;
	if (*state == strlen(tag)){
	    *state = 0;
	    retval = 1;
	}
    }
    else
	*state = 0;
    return retval;
}

/*
 * target_locked
 * return 1 if locked, 0 if not.
 * return clientid if locked.
 */
int
target_locked(enum target_type target, int *client)
{
    return 0;
}

/*
 * unlock_target
 */
int
unlock_target(enum target_type target)
{
    return 0;
}

int
lock_target(enum target_type target)
{
    return 0;
}

/*! Get "target" attribute, return actual database given candidate or running
 * Caller must do error handling
 * @retval  dbname   Actual database file name
 */
char *
netconf_get_target(clicon_handle h, cxobj *xn, char *path)
{
    cxobj *x;    
    char  *target = NULL;
    char  *running_db;
    char  *candidate_db;

    if ((running_db = clicon_running_db(h)) == NULL)
	goto done;
    if ((candidate_db = clicon_candidate_db(h)) == NULL)
	goto done;
    if ((x = xpath_first(xn, path)) != NULL){
	if (xpath_first(x, "candidate") != NULL)
	    target = candidate_db;
	else
	if (xpath_first(x, "running") != NULL)
	    target = running_db;
    }
  done:
    return target;
    
}

/*! Send netconf message from cbuf on socket
 * @param[in]   s    
 * @param[in]   cb   Cligen buffer that contains the XML message
 * @param[in]   msg  Only for debug
 */
int 
netconf_output(int s, cbuf *xf, char *msg)
{
    char *buf = cbuf_get(xf);
    int len = cbuf_len(xf);
    int retval = -1;

    clicon_debug(1, "SEND %s", msg);
    if (debug > 1){ /* XXX: below only works to stderr, clicon_debug may log to syslog */
	cxobj *xt = NULL;
	if (clicon_xml_parse_string(&buf, &xt) == 0){
	    clicon_xml2file(stderr, xml_child_i(xt, 0), 0, 0);
	    fprintf(stderr, "\n");
	    xml_free(xt);
	}
    }
    if (write(s, buf, len) < 0){
	if (errno == EPIPE)
	    ;
	else
	    clicon_log(LOG_ERR, "%s: write: %s", __FUNCTION__, strerror(errno));
	goto done;
    }
    retval = 0;
  done:
    return retval;
}