radrelay.c

radius server在linux下的源码

/*
 * radrelay.c	This program tails a detail logfile, reads the log
 *		entries, forwards them to a remote radius server,
 *		and moves the processed records to another file.
 *
 *		Used to replicate accounting records to one (central)
 *		server - works even if remote server has extended
 *		downtime, and/or if this program is restarted.
 *
 *   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
 *
 * Copyright 2001 Cistron Internet Services B.V.
 * Copyright 2002 Simon Ekstrand <[e-mail]>
 *
 */
char radrelay_rcsid[] =
"$Id: radrelay.c,v 1.22.2.2 2005/05/23 09:35:09 nbk Exp $";

#include "autoconf.h"
#include "libradius.h"

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/stat.h>
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif

#include <stdio.h>
#include <fcntl.h>
#include <time.h>
#include <unistd.h>
#include <netdb.h>
#include <stdlib.h>
#include <signal.h>
#include <errno.h>
#include <string.h>

#include "radiusd.h"
#include "conf.h"
#include "radpaths.h"
#include "missing.h"
#include "conffile.h"

const char *progname;

int debug_flag = 0;
const char *radlog_dir = NULL;
radlog_dest_t radlog_dest = RADLOG_FILES;

const char *radius_dir = NULL;
const char *radacct_dir = NULL;
const char *radlib_dir = NULL;
uint32_t myip = INADDR_ANY;
int log_stripped_names;
struct main_config_t mainconfig;

/*
 *	Possible states for request->state
 */
#define		STATE_EMPTY	0
#define		STATE_BUSY1	1
#define		STATE_BUSY2	2
#define		STATE_FULL	3

/*
 *	Possible states for the loop() function.
 */
#define		STATE_RUN	0
#define		STATE_BACKLOG	1
#define		STATE_WAIT	2
#define		STATE_SHUTDOWN	3
#define		STATE_CLOSE	4

#define		NR_SLOTS	64

/*
 *	A relay request.
 */
struct relay_request {
	int		state;				/* REQ_* state */
	time_t		retrans;			/* when to retrans */
	unsigned int	retrans_num;			/* Number of retransmissions */
	time_t		timestamp;			/* orig recv time */
	uint32_t	client_ip;			/* Client-IP-Addr */
	RADIUS_PACKET	*req;				/* Radius request */
};

struct relay_misc {
	int		sockfd;				/* Main socket descriptor */
	uint32_t 	dst_addr;			/* Destination address */
	short 		dst_port;			/* Destination port */
	uint32_t	src_addr;			/* Source address */
	char		detail[1024];			/* Detail file */
	char 		*secret;			/* Secret */
	char		f_secret[256];			/* File secret */
};

/*
 * Used for reading the client configurations from the config files.
 */
char *c_secret = NULL;
char *c_shortname = NULL;

struct relay_request slots[NR_SLOTS];
char id_map[256];
int request_head = 0;
int got_sigterm = 0;
int debug = 0;


int get_radius_id(void);
void sigterm_handler(int sig);
void ms_sleep(int msec);
int isdateline(char *d);
int read_one(FILE *fp, struct relay_request *req);
int do_recv(struct relay_misc *r_args);
int do_send(struct relay_request *r, char *secret);
int detail_move(char *from, char *to);
void loop(struct relay_misc *r_args);
int find_shortname(char *shortname, char **host, char **secret);
void usage(void);


/*
 * Get a radius id which is not
 * currently being used (outstanding request)
 * Since NR_SLOTS < 256 we can't
 * have more outstanding requests than radius ids
 */
int get_radius_id()
{
	unsigned int id = 0;

	for(id = 0; id < 256; id++){
		if (id_map[id] == 0)
			break;
	}
	if (id == 256 || id_map[id] != 0){
		fprintf(stdout, "get_radius_id(): No IDs available. Something is very wrong\n");
		return -1;
	}
	id_map[id] = 1;
	fprintf(stdout, "get_radius_id(): Assign RADIUS ID = %d\n",id);

	return id;
}

void sigterm_handler(int sig)
{
	signal(sig, sigterm_handler);
	got_sigterm = 1;
}


/*
 *	Sleep a number of milli seconds
 */
void ms_sleep(int msec)
{
	struct timeval tv;

	tv.tv_sec  = (msec / 1000);
	tv.tv_usec = (msec % 1000) * 1000;
	select(0, NULL, NULL, NULL, &tv);
}

/*
 *	Does this (remotely) look like "Tue Jan 23 06:55:48 2001" ?
 */
int isdateline(char *d)
{
	int y;

	return sscanf(d, "%*s %*s %*d %*d:%*d:%*d %d", &y);
}


/*
 *	Read one request from the detail file.
 *	Note that the file is locked during the read, and that
 *	we return *with the file locked* if we reach end-of-file.
 *
 *	STATE_EMPTY:	Slot is empty.
 *	STATE_BUSY1:	Looking for start of a detail record (timestamp)
 *	STATE_BUSY2:	Reading the A/V pairs of a detail record.
 *	STATE_FULL:	Read the complete record.
 *
 */
int read_one(FILE *fp, struct relay_request *r_req)
{
	VALUE_PAIR *vp;
	char *s;
	char buf[256];
	char key[32], val[32];
	int skip;
	long fpos;
	int x;
	unsigned int i = 0;

	/* Never happens */
	if (r_req->state == STATE_FULL)
		return 0;

	if (r_req->state == STATE_EMPTY) {
		r_req->state = STATE_BUSY1;
	}

	/*
	 * Try to lock the detail-file.
	 * If lockf is used we want to lock the _whole_ file, hence the
	 * fseek to the start of the file.
	 */
	fpos = ftell(fp);
	fseek(fp, 0L, SEEK_SET);
	do {
		x = rad_lockfd_nonblock(fileno(fp), 0);
		if (x == -1)
			ms_sleep(100);
	} while (x == -1 && i++ < 20);

	if (x == -1)
		return 0;

redo:
	s = NULL;
	fseek(fp, fpos, SEEK_SET);
	fpos = ftell(fp);
	while ((s = fgets(buf, sizeof(buf), fp)) != NULL) {
		/*
		 * Eek! We've just read a broken attribute.
		 * This does seem to happen every once in a long while
		 * due to some quirk involving threading, multiple processes
		 * going for the detail file lock at once and writes not
		 * being flushed properly. Things should be ok next time
		 * around.
		 */
		if (!strlen(buf)) {
			fprintf(stdout, "read_one: ZERO BYTE\n");
                       fseek(fp, fpos + 1, SEEK_SET);
                       break;
               } else if (buf[strlen(buf) - 1] != '\n') {
			fprintf(stdout, "read_one: BROKEN ATTRIBUTE\n");
			fseek(fp, fpos + strlen(buf), SEEK_SET);
			break;
		}
		if (r_req->state == STATE_BUSY1) {
			if (isdateline(buf)) {
				r_req->state = STATE_BUSY2;
			}
		} else if (r_req->state == STATE_BUSY2) {
			if (buf[0] != ' ' && buf[0] != '\t') {
				r_req->state = STATE_FULL;
				break;
			}
			/*
			 *	Found A/V pair, but we skip non-protocol
			 *	values.
			 */
			skip = 0;
			if (sscanf(buf, "%31s = %31s", key, val) == 2) {
				if (!strcasecmp(key, "Timestamp")) {
					r_req->timestamp = atoi(val);
					skip++;
				} else
				if (!strcasecmp(key, "Client-IP-Address")) {
					r_req->client_ip = ip_getaddr(val);
					skip++;
				} else
				if (!strcasecmp(key, "Request-Authenticator"))
					skip++;
			}
			if (!skip) {
				vp = NULL;
				if (userparse(buf, &vp) > 0 &&
				    (vp != NULL) &&
				    (vp->attribute < 256 ||
				     vp->attribute > 65535) &&
				    vp->attribute != PW_VENDOR_SPECIFIC) {
					pairadd(&(r_req->req->vps), vp);
				} else {
				  pairfree(&vp);
				}
			}
		}
		fpos = ftell(fp);
	}
	clearerr(fp);

	if (r_req->state == STATE_FULL) {
		/*
		 *	w00 - we just completed reading a record in full.
		 */

		/*
		 * Check that we have an Acct-Status-Type attribute. If not
		 * reject the record
		 */
		if (pairfind(r_req->req->vps, PW_ACCT_STATUS_TYPE) == NULL){
			fprintf(stdout, "read_one: No Acct-Status-Type attribute present. Rejecting record.\n");
			r_req->state = STATE_BUSY1;
			if (r_req->req->vps != NULL) {
				pairfree(&r_req->req->vps);
				r_req->req->vps = NULL;
			}
			if (r_req->req->data != NULL) {
				free (r_req->req->data);
				r_req->req->data = NULL;
			}
			r_req->retrans = 0;
			r_req->retrans_num = 0;
			r_req->timestamp = 0;
			r_req->client_ip = 0;
			goto redo;
		}
		if (r_req->timestamp == 0)
			r_req->timestamp = time(NULL);
		if ((vp = pairfind(r_req->req->vps, PW_ACCT_DELAY_TIME)) != NULL) {
			r_req->timestamp -= vp->lvalue;
			vp->lvalue = 0;
		}
		r_req->req->id = get_radius_id();
	}

	if (s == NULL) {
		/*
		 *	Apparently we reached end of file. If we didn't
		 *	partially read a record, we let the caller know
		 *	we're at end of file.
		 */
		if (r_req->state == STATE_BUSY1) {
			r_req->state = STATE_EMPTY;
		}
		if (r_req->state == STATE_EMPTY || r_req->state == STATE_FULL)
			return EOF;
	}

	fpos = ftell(fp);
	fseek(fp, 0L, SEEK_SET);
	rad_unlockfd(fileno(fp), 0);
	fseek(fp, fpos, SEEK_SET);

	return 0;
}

/*
 *	Receive answers from the remote server.
 */
int do_recv(struct relay_misc *r_args)
{
	RADIUS_PACKET *rep;
	struct relay_request *r;
	int i;

	/*
	 *	Receive packet and validate it's length.
	 */
	rep = rad_recv(r_args->sockfd);
	if (rep == NULL) {
		librad_perror("radrelay:");
		return -1;
	}

	/*
	 *	Must be an accounting response.
	 *	FIXME: check if this is the right server!
	 */
	if (rep->code != PW_ACCOUNTING_RESPONSE)
		return -1;

	/*
	 *	Decode packet into radius attributes.
	 */

	/*
	 *	Now find it in the outstanding requests.
	 */
	for (i = 0; i < NR_SLOTS; i++) {
		r = slots + i;
		if (r->state == STATE_FULL && r->req->id == rep->id) {
			if (rad_decode(rep, r->req, r_args->secret) != 0) {
				librad_perror("rad_decode");
				return -1;
			}
			/*
			 *	Got it. Clear slot.
			 *	FIXME: check reponse digest ?
			 */
			id_map[r->req->id] = 0;
			fprintf(stdout, "do_recv: Free RADIUS ID = %d\n",r->req->id);
			if (r->req->vps != NULL) {
				pairfree(&r->req->vps);
				r->req->vps = NULL;
			}
			if (r->req->data != NULL) {
				free (r->req->data);
				r->req->data = NULL;
			}
			r->state = STATE_EMPTY;
			r->retrans = 0;
			r->retrans_num = 0;
			r->timestamp = 0;
			r->client_ip = 0;
			break;
		}
	}

	rad_free(&rep);

	return 0;
}

/*
 *	Send accounting packet to remote server.
 */
int do_send(struct relay_request *r, char *secret)
{
	VALUE_PAIR *vp;
	time_t now;

	/*
	 *	Prevent loops.
	 */
	if (r->client_ip == r->req->dst_ipaddr) {
		fprintf(stdout, "do_send: Client-IP == Dest-IP. Droping packet.\n");
		fprintf(stdout, "do_send: Free RADIUS ID = %d\n",r->req->id);
		id_map[r->req->id] = 0;
		if (r->req->vps != NULL) {
			pairfree(&r->req->vps);
			r->req->vps = NULL;
		}
		if (r->req->data != NULL) {
			free (r->req->data);
			r->req->data = NULL;
		}
		r->state = STATE_EMPTY;
		r->retrans = 0;
		r->retrans_num = 0;
		r->timestamp = 0;
		r->client_ip = 0;
		return 0;
	}

	/*
	 *	Has the time come for this packet ?
	 */
	now = time(NULL);
	if (r->retrans > now)
		return 0;
	/*
	 * If we are resending a packet we *need* to
	 * change the radius packet id since the request
	 * authenticator is different (due to different
	 * Acct-Delay-Time value).
	 * Otherwise the radius server may consider the
	 * packet a duplicate and we 'll get caught in a
	 * loop.
	 */
	if (r->retrans > 0){
		id_map[r->req->id] = 0;
		r->req->id = get_radius_id();
		if (r->req->data != NULL){
			free(r->req->data);
			r->req->data = NULL;
		}
		r->retrans_num++;
	}
	if (r->retrans_num > 20)
		r->retrans = now + 70;
	else
		r->retrans = now + 3 + (3 * r->retrans_num);

	/*
	 *	Find the Acct-Delay-Time attribute. If it's
	 *	not there, add one.
	 */
	if ((vp = pairfind(r->req->vps, PW_ACCT_DELAY_TIME)) == NULL) {
		vp = paircreate(PW_ACCT_DELAY_TIME, PW_TYPE_INTEGER);
		pairadd(&(r->req->vps), vp);
	}
	vp->lvalue = (now - r->timestamp);

	/*
	 *	Rebuild the entire packet every time from
	 *	scratch - the signature changed because
	 *	Acct-Delay-Time changed.
	 */
	rad_send(r->req, NULL, secret);

	return 1;
}

/*
 *	Rename a file, then recreate the old file with the
 *	same permissions and zero size.
 */
int detail_move(char *from, char *to)
{
	struct stat st;
	int n;
	int oldmask;

	if (stat(from, &st) < 0)