/*
* This function is invoked in a forked process to run a server.
* If the service is internal the appropriate function is invoked
* otherwise the server program is exec'ed.
* This function also logs the remote user id if appropriate
*/
void child_process( struct server *serp )
{
struct service *sp = SERVER_SERVICE( serp ) ;
connection_s *cp = SERVER_CONNECTION( serp ) ;
struct service_config *scp = SVC_CONF( sp ) ;
const char *func = "child_process" ;
signal_default_state();
if ((signals_pending[0] >= 0 && Sclose(signals_pending[0])) ||
(signals_pending[1] >= 0 && Sclose(signals_pending[1])))
{
msg(LOG_ERR, func, "Failed to close the signal pipe: %m");
_exit(1);
}
signals_pending[0] = -1;
signals_pending[1] = -1;
Sclose(0);
Sclose(1);
Sclose(2);
#ifdef DEBUG_SERVER
if ( debug.on )
{
msg( LOG_DEBUG, func, "Process %d is sleeping", getpid() ) ;
sleep( 10 ) ;
}
#endif
if ( ! SC_IS_INTERCEPTED( scp ) )
{
set_credentials( scp ) ;
if ( SC_SPECIFIED( scp, A_NICE ) )
(void) nice( SC_NICE( scp ) ) ;
}
if ( svc_child_access_control(sp, cp) != OK )
exit(0);
if ( SERVER_LOGUSER( serp ) )
{
unsigned timeout ;
idresult_e result ;
/*
* We use LOGUSER_SUCCESS_TIMEOUT unless the service requires
* identification, in which case we use an infinite timeout
*/
timeout = SC_MUST_IDENTIFY( scp ) ? 0 : LOGUSER_SUCCESS_TIMEOUT ;
result = log_remote_user( serp, timeout ) ;
if ( result != IDR_OK && SC_MUST_IDENTIFY( scp ) )
{
svc_logprint( sp, NOID_ENTRY, "%s %s",
conn_addrstr( SERVER_CONNECTION( serp ) ),
idresult_explain( result ) ) ;
_exit( 0 ) ;
}
}
#ifdef HAVE_SESSIONCREATE
if ( scp->sc_sessioncreate == YES )
{
if ( SessionCreate(0, sessionHasTTY|sessionIsRemote) != noErr )
svc_logprint( sp, "SessionCreate", "SessionCreate() failed!" );
}
#endif
/* this is where the server gets executed -bbraun */
if ( ! SC_IS_INTERNAL( scp ) )
{
if( scp->sc_redir_addr != NULL )
{
redir_handler( serp );
}
else
{
#if defined(HAVE_SETENV)
char buff[1024];
strx_sprint(buff, sizeof(buff)-1, "REMOTE_HOST=%s", conn_addrstr(cp));
if( env_addstr(SC_ENV(scp)->env_handle, buff) != ENV_OK ) {
msg( LOG_ERR, func, "Error adding REMOTE_HOST variable for %s: %m", SC_NAME(scp) );
_exit( 1 ) ;
}
#endif
exec_server( serp ) ;
}
}
else
{
char name[ 180 ] ;
/*
* We don't bother to disassociate from the controlling terminal
* (we have a controlling terminal only if debug.on is TRUE)
*
* Also, for interceptor processes, we give them the name:
* <program_name> <service-id> interceptor
*/
if ( SC_IS_INTERCEPTED( scp ) )
strx_print( INT_NULL, name, sizeof( name ) - 1,
"%s %s interceptor", program_name, SC_ID( scp ) ) ;
else
{
int namelen = sizeof( name ) - 1 ; /* leave space for the NUL */
char host[NI_MAXHOST];
size_t hostlen = NI_MAXHOST;
socklen_t addrlen = 0;
union xsockaddr *sinp = CONN_XADDRESS(SERVER_CONNECTION(serp));
int len;
if( sinp == NULL )
exit(0);
if( SC_IPV6(scp) ) addrlen = sizeof(struct sockaddr_in6);
else if( SC_IPV4(scp) ) addrlen = sizeof(struct sockaddr_in);
len = strx_nprint(name, namelen, "(%s service) %s", program_name,
SC_ID( scp ) ) ;
if( getnameinfo( SA(sinp), addrlen, host, hostlen, NULL, 0, 0) != 0 )
strcpy(host, "unknown");
if ( SC_IPV6(scp) && SC_ACCEPTS_CONNECTIONS( scp ) &&
!IN6_IS_ADDR_UNSPECIFIED(&sinp->sa_in6.sin6_addr) )
strx_print( INT_NULL, &name[ len ], namelen - len, " %s" , host ) ;
if ( SC_IPV4(scp) && SC_ACCEPTS_CONNECTIONS( scp ) )
strx_print( INT_NULL, &name[ len ], namelen - len, " %s", host ) ;
}
rename_process( name ) ;
SVC_INTERNAL( sp, serp ) ;
}
_exit( 0 ) ;
/* NOTREACHED */
}
/*
* This function always runs in a forked process.
*/
idresult_e log_remote_user( const struct server *serp, unsigned timeout )
{
static char buf[ IBUFSIZE ] ;
int cc ;
union xsockaddr sin_local, sin_remote, sin_contact, sin_bind;
volatile unsigned local_port;
volatile unsigned remote_port;
int sd ;
socklen_t sin_len ;
char *p ;
const char *func = "log_remote_user" ;
if ( timeout && signal( SIGALRM, sigalrm_handler ) == SIG_ERR )
{
msg( LOG_ERR, func, "signal: %m" ) ;
return( IDR_ERROR ) ;
}
/*
* Determine local and remote addresses
*/
sin_len = sizeof( sin_local ) ;
if ( getsockname( SERVER_FD( serp ), &sin_local.sa, &sin_len ) == -1 )
{
msg( LOG_ERR, func, "(%d) getsockname: %m", getpid() ) ;
return( IDR_ERROR ) ;
}
if ( CONN_XADDRESS( SERVER_CONNECTION( serp ) ) == NULL )
{
/*
* This shouldn't happen since identification only works for
* connection-based services.
*/
msg( LOG_ERR, func, "connection has no address" ) ;
return( IDR_ERROR ) ;
}
CLEAR( sin_contact );
sin_remote = *CONN_XADDRESS( SERVER_CONNECTION( serp ) ) ;
sin_contact = sin_remote;
memcpy( &sin_bind, &sin_local, sizeof(sin_bind) ) ;
local_port = 0;
remote_port = 0;
if( sin_remote.sa.sa_family == AF_INET ) {
local_port = ntohs( sin_local.sa_in6.sin6_port ) ;
remote_port = ntohs( sin_remote.sa_in6.sin6_port ) ;
sin_contact.sa_in6.sin6_port = htons( IDENTITY_SERVICE_PORT ) ;
sin_bind.sa_in.sin_port = 0 ;
} else if( sin_remote.sa.sa_family == AF_INET6 ) {
local_port = ntohs( sin_local.sa_in.sin_port ) ;
remote_port = ntohs( sin_remote.sa_in.sin_port ) ;
sin_contact.sa_in.sin_port = htons( IDENTITY_SERVICE_PORT ) ;
sin_bind.sa_in6.sin6_port = 0 ;
}
/*
* Create a socket, bind it, and set the close-on-exec flag on the
* descriptor. We set the flag in case we are called as part of a
* successful attempt to start a server (i.e. execve will follow).
* The socket must be bound to the receiving address or ident might
* fail for multi-homed hosts.
*/
sd = socket( sin_remote.sa.sa_family, SOCK_STREAM, 0 ) ;
if ( sd == -1 )
{
msg( LOG_ERR, func, "socket creation: %m" ) ;
return( IDR_ERROR ) ;
}
if ( bind(sd, &sin_bind.sa, sizeof(sin_bind.sa)) == -1 )
{
msg( LOG_ERR, func, "socket bind: %m" ) ;
(void) Sclose( sd ) ;
return( IDR_ERROR ) ;
}
if ( fcntl( sd, F_SETFD, FD_CLOEXEC ) == -1 )
{
msg( LOG_ERR, func, "fcntl F_SETFD: %m" ) ;
(void) Sclose( sd ) ;
return( IDR_ERROR ) ;
}
if ( timeout ) {
if ( sigsetjmp( env, 1 ) == 0 )
START_TIMER( timeout ) ;
else {
Sclose( sd ) ;
return( IDR_TIMEDOUT ) ;
}
}
if ( connect( sd, &sin_contact.sa, sizeof( sin_contact ) ) == -1 )
{
if ( timeout ) {
STOP_TIMER() ;
signal ( SIGALRM, SIG_DFL ) ;
}
Sclose( sd );
return( IDR_NOSERVER ) ;
}
cc = strx_nprint( buf, sizeof( buf ),
"%d,%d\r\n", remote_port, local_port ) ;
if ( write_buf( sd, buf, cc ) == FAILED )
{
if ( timeout ) {
STOP_TIMER() ;
signal ( SIGALRM, SIG_DFL ) ;
}
Sclose( sd );
return( IDR_ERROR ) ;
}
p = get_line( sd, buf, sizeof( buf ) ) ;
if ( timeout ) {
STOP_TIMER() ;
signal ( SIGALRM, SIG_DFL ) ;
}
if ( p == NULL ) {
Sclose( sd );
return( IDR_RESPERR ) ;
}
/*
* Verify that the received line is OK
*/
if ( ( p = verify_line( buf, local_port, remote_port ) ) == NULL )
{
msg(LOG_ERR, func, "Bad line received from identity server at %s: %s",
xaddrname( &sin_remote ), buf ) ;
Sclose( sd );
return( IDR_BADRESP ) ;
}
svc_logprint( SERVER_CONNSERVICE( serp ), USERID_ENTRY, "%s", p ) ;
return( IDR_OK ) ;
}