c88fdb1d1d
populate it. Not doing this can result in a garbage sockaddr_in, which will cause connect() to block inside clnttcp_create().
502 lines
13 KiB
C
502 lines
13 KiB
C
#pragma ident "@(#)auth_time.c 1.4 92/11/10 SMI"
|
|
|
|
/*
|
|
* auth_time.c
|
|
*
|
|
* This module contains the private function __rpc_get_time_offset()
|
|
* which will return the difference in seconds between the local system's
|
|
* notion of time and a remote server's notion of time. This must be
|
|
* possible without calling any functions that may invoke the name
|
|
* service. (netdir_getbyxxx, getXbyY, etc). The function is used in the
|
|
* synchronize call of the authdes code to synchronize clocks between
|
|
* NIS+ clients and their servers.
|
|
*
|
|
* Note to minimize the amount of duplicate code, portions of the
|
|
* synchronize() function were folded into this code, and the synchronize
|
|
* call becomes simply a wrapper around this function. Further, if this
|
|
* function is called with a timehost it *DOES* recurse to the name
|
|
* server so don't use it in that mode if you are doing name service code.
|
|
*
|
|
* Copyright (c) 1992 Sun Microsystems Inc.
|
|
* All rights reserved.
|
|
*
|
|
* Side effects :
|
|
* When called a client handle to a RPCBIND process is created
|
|
* and destroyed. Two strings "netid" and "uaddr" are malloc'd
|
|
* and returned. The SIGALRM processing is modified only if
|
|
* needed to deal with TCP connections.
|
|
*
|
|
* NOTE: This code has had the crap beaten out it in order to convert
|
|
* it from TI-RPC back to TD-RPC for use on FreeBSD.
|
|
*/
|
|
#include <stdio.h>
|
|
#include <syslog.h>
|
|
#include <string.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <netdb.h>
|
|
#include <sys/signal.h>
|
|
#include <sys/errno.h>
|
|
#include <sys/socket.h>
|
|
#include <netinet/in.h>
|
|
#include <arpa/inet.h>
|
|
#include <rpc/rpc.h>
|
|
#include <rpc/rpc_com.h>
|
|
#undef NIS
|
|
#include <rpcsvc/nis.h>
|
|
|
|
/*
|
|
* FreeBSD currently uses RPC 4.0, which uses portmap rather than
|
|
* rpcbind. Consequently, we need to fake up these values here.
|
|
* Luckily, the RPCB_GETTIME procedure uses only base XDR data types
|
|
* so we don't need anything besides these magic numbers.
|
|
*/
|
|
#define RPCBPROG (u_long)100000
|
|
#define RPCBVERS (u_long)3
|
|
#define RPCBPROC_GETTIME (u_long)6
|
|
|
|
#ifdef TESTING
|
|
#define msg(x) printf("ERROR: %s\n", x)
|
|
/* #define msg(x) syslog(LOG_ERR, "%s", x) */
|
|
#else
|
|
#define msg(x)
|
|
#endif
|
|
|
|
static int saw_alarm = 0;
|
|
|
|
static void
|
|
alarm_hndler(s)
|
|
int s;
|
|
{
|
|
saw_alarm = 1;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* The internet time server defines the epoch to be Jan 1, 1900
|
|
* whereas UNIX defines it to be Jan 1, 1970. To adjust the result
|
|
* from internet time-service time, into UNIX time we subtract the
|
|
* following offset :
|
|
*/
|
|
#define NYEARS (1970 - 1900)
|
|
#define TOFFSET ((u_long)60*60*24*(365*NYEARS + (NYEARS/4)))
|
|
|
|
|
|
/*
|
|
* Stolen from rpc.nisd:
|
|
* Turn a 'universal address' into a struct sockaddr_in.
|
|
* Bletch.
|
|
*/
|
|
static int uaddr_to_sockaddr(uaddr, sin)
|
|
#ifdef foo
|
|
endpoint *endpt;
|
|
#endif
|
|
char *uaddr;
|
|
struct sockaddr_in *sin;
|
|
{
|
|
unsigned char p_bytes[2];
|
|
int i;
|
|
unsigned long a[6];
|
|
|
|
i = sscanf(uaddr, "%lu.%lu.%lu.%lu.%lu.%lu", &a[0], &a[1], &a[2],
|
|
&a[3], &a[4], &a[5]);
|
|
|
|
if (i < 6)
|
|
return(1);
|
|
|
|
for (i = 0; i < 4; i++)
|
|
sin->sin_addr.s_addr |= (a[i] & 0x000000FF) << (8 * i);
|
|
|
|
p_bytes[0] = (unsigned char)a[4] & 0x000000FF;
|
|
p_bytes[1] = (unsigned char)a[5] & 0x000000FF;
|
|
|
|
sin->sin_family = AF_INET; /* always */
|
|
bcopy((char *)&p_bytes, (char *)&sin->sin_port, 2);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* free_eps()
|
|
*
|
|
* Free the strings that were strduped into the eps structure.
|
|
*/
|
|
static void
|
|
free_eps(eps, num)
|
|
endpoint eps[];
|
|
int num;
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < num; i++) {
|
|
free(eps[i].uaddr);
|
|
free(eps[i].proto);
|
|
free(eps[i].family);
|
|
}
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* get_server()
|
|
*
|
|
* This function constructs a nis_server structure description for the
|
|
* indicated hostname.
|
|
*
|
|
* NOTE: There is a chance we may end up recursing here due to the
|
|
* fact that gethostbyname() could do an NIS search. Ideally, the
|
|
* NIS+ server will call __rpc_get_time_offset() with the nis_server
|
|
* structure already populated.
|
|
*/
|
|
static nis_server *
|
|
get_server(sin, host, srv, eps, maxep)
|
|
struct sockaddr_in *sin;
|
|
char *host; /* name of the time host */
|
|
nis_server *srv; /* nis_server struct to use. */
|
|
endpoint eps[]; /* array of endpoints */
|
|
int maxep; /* max array size */
|
|
{
|
|
char hname[256];
|
|
int num_ep = 0, i;
|
|
struct hostent *he;
|
|
struct hostent dummy;
|
|
char *ptr[2];
|
|
|
|
if (host == NULL && sin == NULL)
|
|
return (NULL);
|
|
|
|
if (sin == NULL) {
|
|
he = gethostbyname(host);
|
|
if (he == NULL)
|
|
return(NULL);
|
|
} else {
|
|
he = &dummy;
|
|
ptr[0] = (char *)&sin->sin_addr.s_addr;
|
|
ptr[1] = NULL;
|
|
dummy.h_addr_list = ptr;
|
|
}
|
|
|
|
/*
|
|
* This is lame. We go around once for TCP, then again
|
|
* for UDP.
|
|
*/
|
|
for (i = 0; (he->h_addr_list[i] != NULL) && (num_ep < maxep);
|
|
i++, num_ep++) {
|
|
struct in_addr *a;
|
|
|
|
a = (struct in_addr *)he->h_addr_list[i];
|
|
snprintf(hname, sizeof(hname), "%s.0.111", inet_ntoa(*a));
|
|
eps[num_ep].uaddr = strdup(hname);
|
|
eps[num_ep].family = strdup("inet");
|
|
eps[num_ep].proto = strdup("tcp");
|
|
}
|
|
|
|
for (i = 0; (he->h_addr_list[i] != NULL) && (num_ep < maxep);
|
|
i++, num_ep++) {
|
|
struct in_addr *a;
|
|
|
|
a = (struct in_addr *)he->h_addr_list[i];
|
|
snprintf(hname, sizeof(hname), "%s.0.111", inet_ntoa(*a));
|
|
eps[num_ep].uaddr = strdup(hname);
|
|
eps[num_ep].family = strdup("inet");
|
|
eps[num_ep].proto = strdup("udp");
|
|
}
|
|
|
|
srv->name = (nis_name) host;
|
|
srv->ep.ep_len = num_ep;
|
|
srv->ep.ep_val = eps;
|
|
srv->key_type = NIS_PK_NONE;
|
|
srv->pkey.n_bytes = NULL;
|
|
srv->pkey.n_len = 0;
|
|
return (srv);
|
|
}
|
|
|
|
/*
|
|
* __rpc_get_time_offset()
|
|
*
|
|
* This function uses a nis_server structure to contact the a remote
|
|
* machine (as named in that structure) and returns the offset in time
|
|
* between that machine and this one. This offset is returned in seconds
|
|
* and may be positive or negative.
|
|
*
|
|
* The first time through, a lot of fiddling is done with the netconfig
|
|
* stuff to find a suitable transport. The function is very aggressive
|
|
* about choosing UDP or at worst TCP if it can. This is because
|
|
* those transports support both the RCPBIND call and the internet
|
|
* time service.
|
|
*
|
|
* Once through, *uaddr is set to the universal address of
|
|
* the machine and *netid is set to the local netid for the transport
|
|
* that uaddr goes with. On the second call, the netconfig stuff
|
|
* is skipped and the uaddr/netid pair are used to fetch the netconfig
|
|
* structure and to then contact the machine for the time.
|
|
*
|
|
* td = "server" - "client"
|
|
*/
|
|
int
|
|
__rpc_get_time_offset(td, srv, thost, uaddr, netid)
|
|
struct timeval *td; /* Time difference */
|
|
nis_server *srv; /* NIS Server description */
|
|
char *thost; /* if no server, this is the timehost */
|
|
char **uaddr; /* known universal address */
|
|
struct sockaddr_in *netid; /* known network identifier */
|
|
{
|
|
CLIENT *clnt; /* Client handle */
|
|
endpoint *ep, /* useful endpoints */
|
|
*useep = NULL; /* endpoint of xp */
|
|
char *useua = NULL; /* uaddr of selected xp */
|
|
int epl, i; /* counters */
|
|
enum clnt_stat status; /* result of clnt_call */
|
|
u_long thetime, delta;
|
|
int needfree = 0;
|
|
struct timeval tv;
|
|
int time_valid;
|
|
int udp_ep = -1, tcp_ep = -1;
|
|
int a1, a2, a3, a4;
|
|
char ut[64], ipuaddr[64];
|
|
endpoint teps[32];
|
|
nis_server tsrv;
|
|
void (*oldsig)() = NULL; /* old alarm handler */
|
|
struct sockaddr_in sin;
|
|
int s = RPC_ANYSOCK, len;
|
|
int type = 0;
|
|
|
|
td->tv_sec = 0;
|
|
td->tv_usec = 0;
|
|
|
|
/*
|
|
* First check to see if we need to find and address for this
|
|
* server.
|
|
*/
|
|
if (*uaddr == NULL) {
|
|
if ((srv != NULL) && (thost != NULL)) {
|
|
msg("both timehost and srv pointer used!");
|
|
return (0);
|
|
}
|
|
if (! srv) {
|
|
srv = get_server(netid, thost, &tsrv, teps, 32);
|
|
if (srv == NULL) {
|
|
msg("unable to contruct server data.");
|
|
return (0);
|
|
}
|
|
needfree = 1; /* need to free data in endpoints */
|
|
}
|
|
|
|
ep = srv->ep.ep_val;
|
|
epl = srv->ep.ep_len;
|
|
|
|
/* Identify the TCP and UDP endpoints */
|
|
for (i = 0;
|
|
(i < epl) && ((udp_ep == -1) || (tcp_ep == -1)); i++) {
|
|
if (strcasecmp(ep[i].proto, "udp") == 0)
|
|
udp_ep = i;
|
|
if (strcasecmp(ep[i].proto, "tcp") == 0)
|
|
tcp_ep = i;
|
|
}
|
|
|
|
/* Check to see if it is UDP or TCP */
|
|
if (tcp_ep > -1) {
|
|
useep = &ep[tcp_ep];
|
|
useua = ep[tcp_ep].uaddr;
|
|
type = SOCK_STREAM;
|
|
} else if (udp_ep > -1) {
|
|
useep = &ep[udp_ep];
|
|
useua = ep[udp_ep].uaddr;
|
|
type = SOCK_DGRAM;
|
|
}
|
|
|
|
if (useep == NULL) {
|
|
msg("no acceptable transport endpoints.");
|
|
if (needfree)
|
|
free_eps(teps, tsrv.ep.ep_len);
|
|
return (0);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Create a sockaddr from the uaddr.
|
|
*/
|
|
if (*uaddr != NULL)
|
|
useua = *uaddr;
|
|
|
|
/* Fixup test for NIS+ */
|
|
sscanf(useua, "%d.%d.%d.%d.", &a1, &a2, &a3, &a4);
|
|
sprintf(ipuaddr, "%d.%d.%d.%d.0.111", a1, a2, a3, a4);
|
|
useua = &ipuaddr[0];
|
|
|
|
bzero((char *)&sin, sizeof(sin));
|
|
if (uaddr_to_sockaddr(useua, &sin)) {
|
|
msg("unable to translate uaddr to sockaddr.");
|
|
if (needfree)
|
|
free_eps(teps, tsrv.ep.ep_len);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Create the client handle to rpcbind. Note we always try
|
|
* version 3 since that is the earliest version that supports
|
|
* the RPCB_GETTIME call. Also it is the version that comes
|
|
* standard with SVR4. Since most everyone supports TCP/IP
|
|
* we could consider trying the rtime call first.
|
|
*/
|
|
clnt = clnttcp_create(&sin, RPCBPROG, RPCBVERS, &s, 0, 0);
|
|
if (clnt == NULL) {
|
|
msg("unable to create client handle to rpcbind.");
|
|
if (needfree)
|
|
free_eps(teps, tsrv.ep.ep_len);
|
|
return (0);
|
|
}
|
|
|
|
tv.tv_sec = 5;
|
|
tv.tv_usec = 0;
|
|
time_valid = 0;
|
|
status = clnt_call(clnt, RPCBPROC_GETTIME, xdr_void, NULL,
|
|
xdr_u_long, (char *)&thetime, tv);
|
|
/*
|
|
* The only error we check for is anything but success. In
|
|
* fact we could have seen PROGMISMATCH if talking to a 4.1
|
|
* machine (pmap v2) or TIMEDOUT if the net was busy.
|
|
*/
|
|
if (status == RPC_SUCCESS)
|
|
time_valid = 1;
|
|
else {
|
|
int save;
|
|
|
|
/* Blow away possible stale CLNT handle. */
|
|
if (clnt != NULL) {
|
|
clnt_destroy(clnt);
|
|
clnt = NULL;
|
|
}
|
|
|
|
/*
|
|
* Convert PMAP address into timeservice address
|
|
* We take advantage of the fact that we "know" what
|
|
* the universal address looks like for inet transports.
|
|
*
|
|
* We also know that the internet timeservice is always
|
|
* listening on port 37.
|
|
*/
|
|
sscanf(useua, "%d.%d.%d.%d.", &a1, &a2, &a3, &a4);
|
|
sprintf(ut, "%d.%d.%d.%d.0.37", a1, a2, a3, a4);
|
|
|
|
if (uaddr_to_sockaddr(ut, &sin)) {
|
|
msg("cannot convert timeservice uaddr to sockaddr.");
|
|
goto error;
|
|
}
|
|
|
|
s = socket(AF_INET, type, 0);
|
|
if (s == -1) {
|
|
msg("unable to open fd to network.");
|
|
goto error;
|
|
}
|
|
|
|
/*
|
|
* Now depending on whether or not we're talking to
|
|
* UDP we set a timeout or not.
|
|
*/
|
|
if (type == SOCK_DGRAM) {
|
|
struct timeval timeout = { 20, 0 };
|
|
struct sockaddr_in from;
|
|
fd_set readfds;
|
|
int res;
|
|
|
|
if (sendto(s, &thetime, sizeof(thetime), 0,
|
|
(struct sockaddr *)&sin, sizeof(sin)) == -1) {
|
|
msg("udp : sendto failed.");
|
|
goto error;
|
|
}
|
|
do {
|
|
FD_ZERO(&readfds);
|
|
FD_SET(s, &readfds);
|
|
res = select(_rpc_dtablesize(), &readfds,
|
|
(fd_set *)NULL, (fd_set *)NULL, &timeout);
|
|
} while (res < 0 && errno == EINTR);
|
|
if (res <= 0)
|
|
goto error;
|
|
len = sizeof(from);
|
|
res = recvfrom(s, (char *)&thetime, sizeof(thetime), 0,
|
|
(struct sockaddr *)&from, &len);
|
|
if (res == -1) {
|
|
msg("recvfrom failed on udp transport.");
|
|
goto error;
|
|
}
|
|
time_valid = 1;
|
|
} else {
|
|
int res;
|
|
|
|
oldsig = (void (*)())signal(SIGALRM, alarm_hndler);
|
|
saw_alarm = 0; /* global tracking the alarm */
|
|
alarm(20); /* only wait 20 seconds */
|
|
res = connect(s, (struct sockaddr *)&sin, sizeof(sin));
|
|
if (res == -1) {
|
|
msg("failed to connect to tcp endpoint.");
|
|
goto error;
|
|
}
|
|
if (saw_alarm) {
|
|
msg("alarm caught it, must be unreachable.");
|
|
goto error;
|
|
}
|
|
res = read(s, (char *)&thetime, sizeof(thetime));
|
|
if (res != sizeof(thetime)) {
|
|
if (saw_alarm)
|
|
msg("timed out TCP call.");
|
|
else
|
|
msg("wrong size of results returned");
|
|
|
|
goto error;
|
|
}
|
|
time_valid = 1;
|
|
}
|
|
save = errno;
|
|
(void) close(s);
|
|
errno = save;
|
|
s = RPC_ANYSOCK;
|
|
|
|
if (time_valid) {
|
|
thetime = ntohl(thetime);
|
|
thetime = thetime - TOFFSET; /* adjust to UNIX time */
|
|
} else
|
|
thetime = 0;
|
|
}
|
|
|
|
gettimeofday(&tv, 0);
|
|
|
|
error:
|
|
/*
|
|
* clean up our allocated data structures.
|
|
*/
|
|
|
|
if (s != RPC_ANYSOCK)
|
|
(void) close(s);
|
|
|
|
if (clnt != NULL)
|
|
clnt_destroy(clnt);
|
|
|
|
alarm(0); /* reset that alarm if its outstanding */
|
|
if (oldsig) {
|
|
signal(SIGALRM, oldsig);
|
|
}
|
|
|
|
/*
|
|
* note, don't free uaddr strings until after we've made a
|
|
* copy of them.
|
|
*/
|
|
if (time_valid) {
|
|
if (*uaddr == NULL)
|
|
*uaddr = strdup(useua);
|
|
|
|
/* Round to the nearest second */
|
|
tv.tv_sec += (tv.tv_sec > 500000) ? 1 : 0;
|
|
delta = (thetime > tv.tv_sec) ? thetime - tv.tv_sec :
|
|
tv.tv_sec - thetime;
|
|
td->tv_sec = (thetime < tv.tv_sec) ? - delta : delta;
|
|
td->tv_usec = 0;
|
|
} else {
|
|
msg("unable to get the server's time.");
|
|
}
|
|
|
|
if (needfree)
|
|
free_eps(teps, tsrv.ep.ep_len);
|
|
|
|
return (time_valid);
|
|
}
|