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/*
* Ident-2 - an Identity server for UNIX
* Copyright (C) 1998-2001 Michael Bacarella
* Copyright (C) 2003 Netgraft Corporation
*
* 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.
*
* Please view the file README for program information.
*
* Support for FreeBSD machine dependancies
*/
/*
* NOTE: This supports only FreeBSD versions greater than 3.0!
* I do not deem versions less than 3.0 as worth supporting
* because it requires more code as well as decreased security
* for this ident server to function.
*/
#include "ident2.h"
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/protosw.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcpip.h>
#include <netinet/tcp_seq.h>
#define TCPSTATES
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/tcp_debug.h>
#include <arpa/inet.h>
#include <err.h>
#define PID_FILE "/var/run/ident2.pid"
/**
** drop to the lowest permission level
** possible. 'nobody' is ideal for FreeBSD
**/
int
m_reduce_rights (void)
{
struct passwd *pw;
if ((geteuid() && getuid())
|| Dont_Change_Uid == TRUE)
return 0;
if ((pw = getpwnam ("nobody")) == NULL) {
syslog (LOG_ERR, "error: getpwnam(nobody): %s",
strerror (errno));
return -1;
}
if (setuid (pw->pw_uid) == -1) {
syslog (LOG_ERR, "error: setuid(%d): %s",
pw->pw_uid, strerror (errno));
return -1;
}
return 0;
}
/**
** find what user belongs to the connection
** described by LPORT, RPORT, RADDR, and LADDR.
** return the uid.
**/
int
m_get_uid (struct in_addr *laddr, u_short lp,
struct in_addr *raddr, u_short rp)
{
char *mibvar = "net.inet.tcp.pcblist";
char *buf;
struct tcpcb *tp;
struct inpcb *inp;
struct xinpgen *xig, *oxig;
struct xsocket *so;
size_t len;
if (sysctlbyname (mibvar, 0, &len, 0, 0) < 0) {
syslog (LOG_WARNING, "sysctl: %s: %s\n", mibvar,
strerror (errno));
return -1;
}
buf = xmalloc (len);
if (sysctlbyname (mibvar, buf, &len, 0, 0) < 0) {
syslog (LOG_WARNING, "sysctl: %s: %s\n", mibvar,
strerror (errno));
free (buf);
return -1;
}
oxig = xig = (struct xinpgen *)buf;
for (xig = (struct xinpgen *)((char *)xig + xig->xig_len);
xig->xig_len > sizeof(struct xinpgen);
xig = (struct xinpgen *)((char *)xig + xig->xig_len)) {
tp = &((struct xtcpcb *)xig)->xt_tp;
inp = &((struct xtcpcb *)xig)->xt_inp;
so = &((struct xtcpcb *)xig)->xt_socket;
if (so->xso_protocol != IPPROTO_TCP) continue;
if (inp->inp_gencnt > oxig->xig_gen) continue;
if (inet_lnaof(inp->inp_laddr) == INADDR_ANY)
continue;
if ((raddr->s_addr) == inp->inp_faddr.s_addr
&& (laddr->s_addr) == inp->inp_laddr.s_addr
&& rp == ntohs (inp->inp_fport)
&& lp == ntohs (inp->inp_lport)) {
int uid = so->so_uid;
free (buf);
return uid;
}
}
free (buf);
return -1;
}
/*
* FreeBSD seems to like recording this information
* to /var/run. Good. nice and standard.
* PID support suggested (and previously implemented)
* by Alexander Reelsen.
*/
int
m_register_pid (void)
{
#ifdef HAS_VAR_RUN
FILE *fp;
if ((fp = fopen (PID_FILE, "w")) == NULL) {
syslog (LOG_WARNING, "couldn't record pid in %s: %s -- "
"automatic shutdown with system not available",
PID_FILE, strerror (errno));
return -1;
}
fprintf (fp, "%u\n", getpid ());
fclose (fp);
#endif
return 0;
}
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