NetBSD-5.0.2/usr.sbin/sup/source/scm.c
/* $NetBSD: scm.c,v 1.25 2007/12/20 20:17:15 christos Exp $ */
/*
* Copyright (c) 1992 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
* SUP Communication Module for 4.3 BSD
*
* SUP COMMUNICATION MODULE SPECIFICATIONS:
*
* IN THIS MODULE:
*
* CONNECTION ROUTINES
*
* FOR SERVER
* servicesetup (port) establish TCP port connection
* char *port; name of service
* service () accept TCP port connection
* servicekill () close TCP port in use by another process
* serviceprep () close temp ports used to make connection
* serviceend () close TCP port
*
* FOR CLIENT
* request (port,hostname,retry) establish TCP port connection
* char *port,*hostname; name of service and host
* int retry; true if retries should be used
* requestend () close TCP port
*
* HOST NAME CHECKING
* p = remotehost () remote host name (if known)
* char *p;
* i = samehost () whether remote host is also this host
* int i;
* i = matchhost (name) whether remote host is same as name
* int i;
* char *name;
*
* RETURN CODES
* All procedures return values as indicated above. Other routines
* normally return SCMOK on success, SCMERR on error.
*
* COMMUNICATION PROTOCOL
*
* Described in scmio.c.
*
**********************************************************************
* HISTORY
* 2-Oct-92 Mary Thompson (mrt) at Carnegie-Mellon University
* Added conditional declarations of INADDR_NONE and INADDR_LOOPBACK
* since Tahoe version of <netinet/in.h> does not define them.
*
* Revision 1.13 92/08/11 12:05:35 mrt
* Added changes from stump:
* Allow for multiple interfaces, and for numeric addresses.
* Changed to use builtin port for the "supfiledbg"
* service when getservbyname() cannot find it.
* Added forward static declatations, delinted.
* Updated variable argument usage.
* [92/08/08 mrt]
*
* Revision 1.12 92/02/08 19:01:11 mja
* Add (struct sockaddr *) casts for HC 2.1.
* [92/02/08 18:59:09 mja]
*
* Revision 1.11 89/08/03 19:49:03 mja
* Updated to use v*printf() in place of _doprnt().
* [89/04/19 mja]
*
* 11-Feb-88 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Moved sleep into computeBackoff, renamed to dobackoff.
*
* 10-Feb-88 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added timeout to backoff.
*
* 27-Dec-87 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Removed nameserver support.
*
* 09-Sep-87 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Fixed to depend less upon having name of remote host.
*
* 25-May-87 Doug Philips (dwp) at Carnegie-Mellon Universtiy
* Extracted backoff/sleeptime computation from "request" and
* created "computeBackoff" so that I could use it in sup.c when
* trying to get to nameservers as a group.
*
* 21-May-87 Chriss Stephens (chriss) at Carnegie Mellon University
* Merged divergent CS and EE versions.
*
* 02-May-87 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added some bullet-proofing code around hostname calls.
*
* 31-Mar-87 Dan Nydick (dan) at Carnegie-Mellon University
* Fixed for 4.3.
*
* 30-May-86 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added code to use known values for well-known ports if they are
* not found in the host table.
*
* 19-Feb-86 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Changed setsockopt SO_REUSEADDR to be non-fatal. Added fourth
* parameter as described in 4.3 manual entry.
*
* 15-Feb-86 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added call of readflush() to requestend() routine.
*
* 29-Dec-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Major rewrite for protocol version 4. All read/write and crypt
* routines are now in scmio.c.
*
* 14-Dec-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added setsockopt SO_REUSEADDR call.
*
* 01-Dec-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Removed code to "gracefully" handle unexpected messages. This
* seems reasonable since it didn't work anyway, and should be
* handled at a higher level anyway by adhering to protocol version
* number conventions.
*
* 26-Nov-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Fixed scm.c to free space for remote host name when connection
* is closed.
*
* 07-Nov-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Fixed 4.2 retry code to reload sin values before retry.
*
* 22-Oct-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added code to retry initial connection open request.
*
* 22-Sep-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Merged 4.1 and 4.2 versions together.
*
* 21-Sep-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Add close() calls after pipe() call.
*
* 12-Jun-85 Steven Shafer (sas) at Carnegie-Mellon University
* Converted for 4.2 sockets; added serviceprep() routine.
*
* 04-Jun-85 Steven Shafer (sas) at Carnegie-Mellon University
* Created for 4.2 BSD.
*
**********************************************************************
*/
#include "libc.h"
#include <errno.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <netdb.h>
#include <stdarg.h>
#if !defined(__linux__)
#if !defined(__CYGWIN__)
#include <ifaddrs.h>
#else
#include "ifaddrs.h"
#endif
#else
#include <sys/ioctl.h>
#endif
#ifdef __CYGWIN__
#include "getaddrinfo.h"
#endif
#include "supcdefs.h"
#include "supextern.h"
#ifndef INADDR_NONE
#define INADDR_NONE 0xffffffff /* -1 return */
#endif
#ifndef INADDR_LOOPBACK
#define INADDR_LOOPBACK (u_long)0x7f000001 /* 127.0.0.1 */
#endif
char scmversion[] = "4.3 BSD";
extern int silent;
/*************************
*** M A C R O S ***
*************************/
/* networking parameters */
#define NCONNECTS 5
/*********************************************
*** G L O B A L V A R I A B L E S ***
*********************************************/
extern char program[]; /* name of program we are running */
extern int progpid; /* process id to display */
int netfile = -1; /* network file descriptor */
static int sock = -1; /* socket used to make connection */
static struct sockaddr_storage remoteaddr; /* remote host address */
static char *remotename = NULL; /* remote host name */
static int swapmode; /* byte-swapping needed on server? */
static char *myhost(void);
/***************************************************
*** C O N N E C T I O N R O U T I N E S ***
*** F O R S E R V E R ***
***************************************************/
int
servicesetup(char *server, int af)
{ /* listen for clients */
struct addrinfo hints, *res0, *res;
char port[NI_MAXSERV];
int error;
const char *cause = "unknown";
int one = 1;
memset(&hints, 0, sizeof(hints));
hints.ai_family = af;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_PASSIVE;
error = getaddrinfo(NULL, server, &hints, &res0);
if (error) {
/* retry with precompiled knowledge */
if (strcmp(server, FILEPORT) == 0)
snprintf(port, sizeof(port), "%u", FILEPORTNUM);
else if (strcmp(server, DEBUGFPORT) == 0)
snprintf(port, sizeof(port), "%u", DEBUGFPORTNUM);
else
port[0] = '\0';
if (port[0])
error = getaddrinfo(NULL, port, &hints, &res0);
if (error)
return (scmerr(-1, "%s: %s", server,
gai_strerror(error)));
}
for (res = res0; res; res = res->ai_next) {
sock = socket(res->ai_family, res->ai_socktype,
res->ai_protocol);
if (sock < 0) {
cause = "socket";
continue;
}
if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
(char *) &one, sizeof(int)) < 0) {
cause = "setsockopt(SO_REUSEADDR)";
close(sock);
continue;
}
if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) {
cause = "bind";
close(sock);
continue;
}
if (listen(sock, NCONNECTS) < 0) {
cause = "listen";
close(sock);
continue;
}
freeaddrinfo(res0);
return SCMOK;
}
freeaddrinfo(res0);
return (scmerr(errno, "%s", cause));
}
int
service(void)
{
struct sockaddr_storage from;
int x;
socklen_t len;
remotename = NULL;
len = sizeof(from);
do {
netfile = accept(sock, (struct sockaddr *) & from, &len);
} while (netfile < 0 && errno == EINTR);
if (netfile < 0)
return (scmerr(errno, "Can't accept connections"));
if (len > sizeof(remoteaddr)) {
close(netfile);
return (scmerr(errno, "Can't accept connections"));
}
memcpy(&remoteaddr, &from, len);
if (read(netfile, (char *) &x, sizeof(int)) != sizeof(int))
return (scmerr(errno, "Can't transmit data on connection"));
if (x == 0x01020304)
swapmode = 0;
else if (x == 0x04030201)
swapmode = 1;
else
return (scmerr(-1, "Unexpected byteswap mode %x", x));
setproctitle("Serving %s", remotehost());
return (SCMOK);
}
int
serviceprep(void)
{ /* kill temp socket in daemon */
if (sock >= 0) {
(void) close(sock);
sock = -1;
}
return (SCMOK);
}
int
servicekill(void)
{ /* kill net file in daemon's parent */
if (netfile >= 0) {
(void) close(netfile);
netfile = -1;
}
if (remotename) {
free(remotename);
remotename = NULL;
}
return (SCMOK);
}
int
serviceend(void)
{ /* kill net file after use in daemon */
if (netfile >= 0) {
(void) close(netfile);
netfile = -1;
}
if (remotename) {
free(remotename);
remotename = NULL;
}
return (SCMOK);
}
/***************************************************
*** C O N N E C T I O N R O U T I N E S ***
*** F O R C L I E N T ***
***************************************************/
int
dobackoff(int *t, int *b)
{
struct timeval tt;
unsigned s;
if (*t == 0)
return (0);
s = *b * 30;
if (gettimeofday(&tt, (struct timezone *) NULL) >= 0)
s += (tt.tv_usec >> 8) % s;
if (*b < 32)
*b <<= 1;
if (*t != -1) {
if (s > *t)
s = *t;
*t -= s;
}
if (!silent)
(void) scmerr(-1, "Will retry in %d seconds", s);
sleep(s);
return (1);
}
int
request(char *server, char *hostname, int *retry)
{ /* connect to server */
struct addrinfo hints, *res, *res0;
int error;
char port[NI_MAXSERV];
int backoff;
int x;
memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
error = getaddrinfo(hostname, server, &hints, &res0);
if (error) {
/* retry with precompiled knowledge */
if (strcmp(server, FILEPORT) == 0)
snprintf(port, sizeof(port), "%u", FILEPORTNUM);
else if (strcmp(server, DEBUGFPORT) == 0)
snprintf(port, sizeof(port), "%u", DEBUGFPORTNUM);
else
port[0] = '\0';
if (port[0])
error = getaddrinfo(hostname, port, &hints, &res0);
if (error)
return (scmerr(-1, "%s: %s", server,
gai_strerror(error)));
}
backoff = 1;
while (1) {
netfile = -1;
for (res = res0; res; res = res->ai_next) {
if (res->ai_addrlen > sizeof(remoteaddr))
continue;
netfile = socket(res->ai_family, res->ai_socktype,
res->ai_protocol);
if (netfile < 0)
continue;
if (connect(netfile, res->ai_addr, res->ai_addrlen) < 0) {
close(netfile);
netfile = -1;
continue;
}
break;
}
if (netfile < 0) {
if (!dobackoff(retry, &backoff)) {
freeaddrinfo(res0);
return (SCMERR);
}
continue;
} else
break;
}
if (res == NULL) {
freeaddrinfo(res0);
return (SCMERR);
}
memcpy(&remoteaddr, res->ai_addr, res->ai_addrlen);
remotename = estrdup(hostname);
x = 0x01020304;
(void) write(netfile, (char *) &x, sizeof(int));
swapmode = 0; /* swap only on server, not client */
freeaddrinfo(res0);
return (SCMOK);
}
int
requestend(void)
{ /* end connection to server */
(void) readflush();
if (netfile >= 0) {
(void) close(netfile);
netfile = -1;
}
if (remotename) {
free(remotename);
remotename = NULL;
}
return (SCMOK);
}
/*************************************************
*** H O S T N A M E C H E C K I N G ***
*************************************************/
static char *
myhost(void)
{ /* find my host name */
struct hostent *h;
static char name[MAXHOSTNAMELEN + 1];
if (name[0] == '\0') {
if (gethostname(name, sizeof name) < 0)
return (NULL);
name[sizeof(name) - 1] = '\0';
if ((h = gethostbyname(name)) == NULL)
return (NULL);
(void) strcpy(name, h->h_name);
}
return (name);
}
char *
remotehost(void)
{ /* remote host name (if known) */
char h1[NI_MAXHOST];
if (remotename == NULL) {
if (getnameinfo((struct sockaddr *) & remoteaddr,
#ifdef BSD4_4
remoteaddr.ss_len,
#else
sizeof(struct sockaddr),
#endif
h1, sizeof(h1), NULL, 0, 0))
return ("UNKNOWN");
remotename = estrdup(h1);
if (remotename == NULL)
return ("UNKNOWN");
}
return (remotename);
}
int
thishost(char *host)
{
struct hostent *h;
char *name;
if ((name = myhost()) == NULL)
logquit(1, "Can't find my host entry '%s'", myhost());
h = gethostbyname(host);
if (h == NULL)
return (0);
return (strcasecmp(name, h->h_name) == 0);
}
#ifdef __linux__
/* Nice and sleazy does it... */
struct ifaddrs {
struct ifaddrs *ifa_next;
struct sockaddr *ifa_addr;
struct sockaddr ifa_addrspace;
};
static int
getifaddrs(struct ifaddrs **ifap)
{
struct ifaddrs *ifa;
int nint;
int n;
char buf[10 * 1024];
struct ifconf ifc;
struct ifreq *ifr;
int s;
if ((s = socket (AF_INET, SOCK_DGRAM, 0)) == -1)
return -1;
ifc.ifc_len = sizeof(buf);
ifc.ifc_buf = buf;
if (ioctl(s, SIOCGIFCONF, &ifc) == -1) {
(void)close(s);
return -1;
}
(void)close(s);
if ((nint = ifc.ifc_len / sizeof(struct ifreq)) <= 0)
return 0;
if ((ifa = malloc((unsigned)nint * sizeof(struct ifaddrs))) == NULL)
return -1;
for (ifr = ifc.ifc_req, n = 0; n < nint; n++, ifr++) {
ifa[n].ifa_next = &ifa[n + 1];
ifa[n].ifa_addr = &ifa[n].ifa_addrspace;
(void)memcpy(ifa[n].ifa_addr, &ifr->ifr_addr,
sizeof(*ifa[n].ifa_addr));
}
ifa[nint - 1].ifa_next = NULL;
*ifap = ifa;
return nint;
}
static void
freeifaddrs(struct ifaddrs *ifa)
{
free(ifa);
}
#endif
int
samehost(void)
{ /* is remote host same as local host? */
struct ifaddrs *ifap, *ifa;
char h1[NI_MAXHOST], h2[NI_MAXHOST];
const int niflags = NI_NUMERICHOST;
if (getnameinfo((struct sockaddr *) &remoteaddr,
#ifdef BSD4_4
remoteaddr.ss_len,
#else
sizeof(struct sockaddr),
#endif
h1, sizeof(h1), NULL, 0, niflags))
return (0);
if (getifaddrs(&ifap) < 0)
return (0);
for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
if (remoteaddr.ss_family != ifa->ifa_addr->sa_family)
continue;
if (getnameinfo(ifa->ifa_addr,
#ifdef BSD4_4
ifa->ifa_addr->sa_len,
#else
sizeof(struct sockaddr),
#endif
h2, sizeof(h2), NULL, 0, niflags))
continue;
if (strcmp(h1, h2) == 0) {
freeifaddrs(ifap);
return (1);
}
}
freeifaddrs(ifap);
return (0);
}
int
matchhost(char *name)
{ /* is this name of remote host? */
char h1[NI_MAXHOST], h2[NI_MAXHOST];
const int niflags = NI_NUMERICHOST;
struct addrinfo hints, *res0, *res;
if (getnameinfo((struct sockaddr *) & remoteaddr,
#ifdef BSD4_4
remoteaddr.ss_len,
#else
sizeof(struct sockaddr),
#endif
h1, sizeof(h1), NULL, 0, niflags))
return (0);
memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_DGRAM; /* dummy */
if (getaddrinfo(name, "0", &hints, &res0) != 0)
return (0);
for (res = res0; res; res = res->ai_next) {
if (remoteaddr.ss_family != res->ai_family)
continue;
if (getnameinfo(res->ai_addr, res->ai_addrlen,
h2, sizeof(h2), NULL, 0, niflags))
continue;
if (strcmp(h1, h2) == 0) {
freeaddrinfo(res0);
return (1);
}
}
freeaddrinfo(res0);
return (0);
}
int
scmerr(int error, char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
(void) fflush(stdout);
if (progpid > 0)
fprintf(stderr, "%s %d: ", program, progpid);
else
fprintf(stderr, "%s: ", program);
vfprintf(stderr, fmt, ap);
va_end(ap);
if (error >= 0)
fprintf(stderr, ": %s\n", errmsg(error));
else
fprintf(stderr, "\n");
(void) fflush(stderr);
return (SCMERR);
}
/*******************************************************
*** I N T E G E R B Y T E - S W A P P I N G ***
*******************************************************/
union intchar {
int ui;
char uc[sizeof(int)];
};
int
byteswap(int in)
{
union intchar x, y;
int ix, iy;
if (swapmode == 0)
return (in);
x.ui = in;
iy = sizeof(int);
for (ix = 0; ix < sizeof(int); ix++) {
--iy;
y.uc[iy] = x.uc[ix];
}
return (y.ui);
}