/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* kprop/kprop.c */
/*
* Copyright 1990,1991,2008 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*/
#include "k5-int.h"
#include <locale.h>
#include <sys/file.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/param.h>
#include <netdb.h>
#include <fcntl.h>
#include "com_err.h"
#include "fake-addrinfo.h"
#include "kprop.h"
#ifndef GETSOCKNAME_ARG3_TYPE
#define GETSOCKNAME_ARG3_TYPE unsigned int
#endif
static char *kprop_version = KPROP_PROT_VERSION;
static char *progname = NULL;
static int debug = 0;
static char *keytab_path = NULL;
static char *replica_host;
static char *realm = NULL;
static char *def_realm = NULL;
static char *file = KPROP_DEFAULT_FILE;
/* The Kerberos principal we'll be sending as, initialized in get_tickets. */
static krb5_principal my_principal;
static krb5_creds creds;
static krb5_address *sender_addr;
static krb5_address *receiver_addr;
static const char *port = KPROP_SERVICE;
static char *dbpathname;
static void parse_args(krb5_context context, int argc, char **argv);
static void get_tickets(krb5_context context);
static void usage(void);
static void open_connection(krb5_context context, char *host, int *fd_out);
static void kerberos_authenticate(krb5_context context,
krb5_auth_context *auth_context, int fd,
krb5_principal me, krb5_creds **new_creds);
static int open_database(krb5_context context, char *data_fn, int *size);
static void close_database(krb5_context context, int fd);
static void xmit_database(krb5_context context,
krb5_auth_context auth_context, krb5_creds *my_creds,
int fd, int database_fd, int in_database_size);
static void send_error(krb5_context context, krb5_creds *my_creds, int fd,
char *err_text, krb5_error_code err_code);
static void update_last_prop_file(char *hostname, char *file_name);
static void usage()
{
fprintf(stderr, _("\nUsage: %s [-r realm] [-f file] [-d] [-P port] "
"[-s keytab] replica_host\n\n"), progname);
exit(1);
}
int
main(int argc, char **argv)
{
int fd, database_fd, database_size;
krb5_error_code retval;
krb5_context context;
krb5_creds *my_creds;
krb5_auth_context auth_context;
setlocale(LC_ALL, "");
retval = krb5_init_context(&context);
if (retval) {
com_err(argv[0], retval, _("while initializing krb5"));
exit(1);
}
parse_args(context, argc, argv);
get_tickets(context);
database_fd = open_database(context, file, &database_size);
open_connection(context, replica_host, &fd);
kerberos_authenticate(context, &auth_context, fd, my_principal, &my_creds);
xmit_database(context, auth_context, my_creds, fd, database_fd,
database_size);
update_last_prop_file(replica_host, file);
printf(_("Database propagation to %s: SUCCEEDED\n"), replica_host);
krb5_free_cred_contents(context, my_creds);
close_database(context, database_fd);
krb5_free_default_realm(context, def_realm);
exit(0);
}
static void
parse_args(krb5_context context, int argc, char **argv)
{
int c;
krb5_error_code ret;
progname = argv[0];
while ((c = getopt(argc, argv, "r:f:dP:s:")) != -1) {
switch (c) {
case 'r':
realm = optarg;
break;
case 'f':
file = optarg;
break;
case 'd':
debug++;
break;
case 'P':
port = optarg;
break;
case 's':
keytab_path = optarg;
break;
default:
usage();
}
}
if (argc - optind != 1)
usage();
replica_host = argv[optind];
if (realm == NULL) {
ret = krb5_get_default_realm(context, &def_realm);
if (ret) {
com_err(progname, errno, _("while getting default realm"));
exit(1);
}
realm = def_realm;
}
}
static void
get_tickets(krb5_context context)
{
char *server;
krb5_error_code retval;
krb5_keytab keytab = NULL;
krb5_principal server_princ = NULL;
/* Figure out what tickets we'll be using to send. */
retval = sn2princ_realm(context, NULL, KPROP_SERVICE_NAME, realm,
&my_principal);
if (retval) {
com_err(progname, errno, _("while setting client principal name"));
exit(1);
}
/* Construct the principal name for the replica host. */
memset(&creds, 0, sizeof(creds));
retval = sn2princ_realm(context, replica_host, KPROP_SERVICE_NAME, realm,
&server_princ);
if (retval) {
com_err(progname, errno, _("while setting server principal name"));
exit(1);
}
retval = krb5_unparse_name_flags(context, server_princ,
KRB5_PRINCIPAL_UNPARSE_NO_REALM, &server);
if (retval) {
com_err(progname, retval, _("while unparsing server name"));
exit(1);
}
if (keytab_path != NULL) {
retval = krb5_kt_resolve(context, keytab_path, &keytab);
if (retval) {
com_err(progname, retval, _("while resolving keytab"));
exit(1);
}
}
retval = krb5_get_init_creds_keytab(context, &creds, my_principal, keytab,
0, server, NULL);
if (retval) {
com_err(progname, retval, _("while getting initial credentials\n"));
exit(1);
}
if (keytab != NULL)
krb5_kt_close(context, keytab);
krb5_free_unparsed_name(context, server);
krb5_free_principal(context, server_princ);
}
static void
open_connection(krb5_context context, char *host, int *fd_out)
{
krb5_error_code retval;
GETSOCKNAME_ARG3_TYPE socket_length;
struct addrinfo hints, *res, *answers;
struct sockaddr *sa;
struct sockaddr_storage my_sin;
int s, error;
*fd_out = -1;
memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_ADDRCONFIG;
error = getaddrinfo(host, port, &hints, &answers);
if (error != 0) {
com_err(progname, 0, "%s: %s", host, gai_strerror(error));
exit(1);
}
s = -1;
retval = EINVAL;
for (res = answers; res != NULL; res = res->ai_next) {
s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
if (s < 0) {
com_err(progname, errno, _("while creating socket"));
exit(1);
}
if (connect(s, res->ai_addr, res->ai_addrlen) < 0) {
retval = errno;
close(s);
s = -1;
continue;
}
/* We successfully connect()ed */
*fd_out = s;
retval = sockaddr2krbaddr(context, res->ai_family, res->ai_addr,
&receiver_addr);
if (retval != 0) {
com_err(progname, retval, _("while converting server address"));
exit(1);
}
break;
}
freeaddrinfo(answers);
if (s == -1) {
com_err(progname, retval, _("while connecting to server"));
exit(1);
}
/* Set sender_addr. */
socket_length = sizeof(my_sin);
if (getsockname(s, (struct sockaddr *)&my_sin, &socket_length) < 0) {
com_err(progname, errno, _("while getting local socket address"));
exit(1);
}
sa = (struct sockaddr *)&my_sin;
if (sockaddr2krbaddr(context, sa->sa_family, sa, &sender_addr) != 0) {
com_err(progname, errno, _("while converting local address"));
exit(1);
}
}
static void
kerberos_authenticate(krb5_context context, krb5_auth_context *auth_context,
int fd, krb5_principal me, krb5_creds **new_creds)
{
krb5_error_code retval;
krb5_error *error = NULL;
krb5_ap_rep_enc_part *rep_result;
retval = krb5_auth_con_init(context, auth_context);
if (retval)
exit(1);
krb5_auth_con_setflags(context, *auth_context,
KRB5_AUTH_CONTEXT_DO_SEQUENCE);
retval = krb5_auth_con_setaddrs(context, *auth_context, sender_addr,
receiver_addr);
if (retval) {
com_err(progname, retval, _("in krb5_auth_con_setaddrs"));
exit(1);
}
retval = krb5_sendauth(context, auth_context, &fd, kprop_version,
me, creds.server, AP_OPTS_MUTUAL_REQUIRED, NULL,
&creds, NULL, &error, &rep_result, new_creds);
if (retval) {
com_err(progname, retval, _("while authenticating to server"));
if (error != NULL) {
if (error->error == KRB_ERR_GENERIC) {
if (error->text.data) {
fprintf(stderr, _("Generic remote error: %s\n"),
error->text.data);
}
} else if (error->error) {
com_err(progname,
(krb5_error_code)error->error + ERROR_TABLE_BASE_krb5,
_("signalled from server"));
if (error->text.data) {
fprintf(stderr, _("Error text from server: %s\n"),
error->text.data);
}
}
krb5_free_error(context, error);
}
exit(1);
}
krb5_free_ap_rep_enc_part(context, rep_result);
}
/*
* Open the Kerberos database dump file. Takes care of locking it
* and making sure that the .ok file is more recent that the database
* dump file itself.
*
* Returns the file descriptor of the database dump file. Also fills
* in the size of the database file.
*/
static int
open_database(krb5_context context, char *data_fn, int *size)
{
struct stat stbuf, stbuf_ok;
char *data_ok_fn;
int fd, err;
dbpathname = strdup(data_fn);
if (dbpathname == NULL) {
com_err(progname, ENOMEM, _("allocating database file name '%s'"),
data_fn);
exit(1);
}
fd = open(dbpathname, O_RDONLY);
if (fd < 0) {
com_err(progname, errno, _("while trying to open %s"), dbpathname);
exit(1);
}
err = krb5_lock_file(context, fd,
KRB5_LOCKMODE_SHARED | KRB5_LOCKMODE_DONTBLOCK);
if (err == EAGAIN || err == EWOULDBLOCK || errno == EACCES) {
com_err(progname, 0, _("database locked"));
exit(1);
} else if (err) {
com_err(progname, err, _("while trying to lock '%s'"), dbpathname);
exit(1);
}
if (fstat(fd, &stbuf)) {
com_err(progname, errno, _("while trying to stat %s"), data_fn);
exit(1);
}
if (asprintf(&data_ok_fn, "%s.dump_ok", data_fn) < 0) {
com_err(progname, ENOMEM, _("while trying to malloc data_ok_fn"));
exit(1);
}
if (stat(data_ok_fn, &stbuf_ok)) {
com_err(progname, errno, _("while trying to stat %s"), data_ok_fn);
free(data_ok_fn);
exit(1);
}
if (stbuf.st_mtime > stbuf_ok.st_mtime) {
com_err(progname, 0, _("'%s' more recent than '%s'."), data_fn,
data_ok_fn);
exit(1);
}
free(data_ok_fn);
*size = stbuf.st_size;
return fd;
}
static void
close_database(krb5_context context, int fd)
{
int err;
err = krb5_lock_file(context, fd, KRB5_LOCKMODE_UNLOCK);
if (err)
com_err(progname, err, _("while unlocking database '%s'"), dbpathname);
free(dbpathname);
close(fd);
}
/*
* Now we send over the database. We use the following protocol:
* Send over a KRB_SAFE message with the size. Then we send over the
* database in blocks of KPROP_BLKSIZE, encrypted using KRB_PRIV.
* Then we expect to see a KRB_SAFE message with the size sent back.
*
* At any point in the protocol, we may send a KRB_ERROR message; this
* will abort the entire operation.
*/
static void
xmit_database(krb5_context context, krb5_auth_context auth_context,
krb5_creds *my_creds, int fd, int database_fd,
int in_database_size)
{
krb5_int32 n;
krb5_data inbuf, outbuf;
char buf[KPROP_BUFSIZ];
krb5_error_code retval;
krb5_error *error;
krb5_ui_4 database_size = in_database_size, send_size, sent_size;
/* Send over the size. */
send_size = htonl(database_size);
inbuf.data = (char *)&send_size;
inbuf.length = sizeof(send_size); /* must be 4, really */
/* KPROP_CKSUMTYPE */
retval = krb5_mk_safe(context, auth_context, &inbuf, &outbuf, NULL);
if (retval) {
com_err(progname, retval, _("while encoding database size"));
send_error(context, my_creds, fd, _("while encoding database size"),
retval);
exit(1);
}
retval = krb5_write_message(context, &fd, &outbuf);
if (retval) {
krb5_free_data_contents(context, &outbuf);
com_err(progname, retval, _("while sending database size"));
exit(1);
}
krb5_free_data_contents(context, &outbuf);
/* Initialize the initial vector. */
retval = krb5_auth_con_initivector(context, auth_context);
if (retval) {
send_error(context, my_creds, fd,
"failed while initializing i_vector", retval);
com_err(progname, retval, _("while allocating i_vector"));
exit(1);
}
/* Send over the file, block by block. */
inbuf.data = buf;
sent_size = 0;
while ((n = read(database_fd, buf, sizeof(buf)))) {
inbuf.length = n;
retval = krb5_mk_priv(context, auth_context, &inbuf, &outbuf, NULL);
if (retval) {
snprintf(buf, sizeof(buf),
"while encoding database block starting at %d",
sent_size);
com_err(progname, retval, "%s", buf);
send_error(context, my_creds, fd, buf, retval);
exit(1);
}
retval = krb5_write_message(context, &fd, &outbuf);
if (retval) {
krb5_free_data_contents(context, &outbuf);
com_err(progname, retval,
_("while sending database block starting at %d"),
sent_size);
exit(1);
}
krb5_free_data_contents(context, &outbuf);
sent_size += n;
if (debug)
printf("%d bytes sent.\n", sent_size);
}
if (sent_size != database_size) {
com_err(progname, 0, _("Premature EOF found for database file!"));
send_error(context, my_creds, fd,
"Premature EOF found for database file!",
KRB5KRB_ERR_GENERIC);
exit(1);
}
/*
* OK, we've sent the database; now let's wait for a success
* indication from the remote end.
*/
retval = krb5_read_message(context, &fd, &inbuf);
if (retval) {
com_err(progname, retval, _("while reading response from server"));
exit(1);
}
/*
* If we got an error response back from the server, display
* the error message
*/
if (krb5_is_krb_error(&inbuf)) {
retval = krb5_rd_error(context, &inbuf, &error);
if (retval) {
com_err(progname, retval,
_("while decoding error response from server"));
exit(1);
}
if (error->error == KRB_ERR_GENERIC) {
if (error->text.data) {
fprintf(stderr, _("Generic remote error: %s\n"),
error->text.data);
}
} else if (error->error) {
com_err(progname,
(krb5_error_code)error->error + ERROR_TABLE_BASE_krb5,
_("signalled from server"));
if (error->text.data) {
fprintf(stderr, _("Error text from server: %s\n"),
error->text.data);
}
}
krb5_free_error(context, error);
exit(1);
}
retval = krb5_rd_safe(context,auth_context,&inbuf,&outbuf,NULL);
if (retval) {
com_err(progname, retval,
"while decoding final size packet from server");
exit(1);
}
memcpy(&send_size, outbuf.data, sizeof(send_size));
send_size = ntohl(send_size);
if (send_size != database_size) {
com_err(progname, 0, _("Kpropd sent database size %d, expecting %d"),
send_size, database_size);
exit(1);
}
free(inbuf.data);
free(outbuf.data);
}
static void
send_error(krb5_context context, krb5_creds *my_creds, int fd, char *err_text,
krb5_error_code err_code)
{
krb5_error error;
const char *text;
krb5_data outbuf;
memset(&error, 0, sizeof(error));
krb5_us_timeofday(context, &error.ctime, &error.cusec);
error.server = my_creds->server;
error.client = my_principal;
error.error = err_code - ERROR_TABLE_BASE_krb5;
if (error.error > 127)
error.error = KRB_ERR_GENERIC;
text = (err_text != NULL) ? err_text : error_message(err_code);
error.text.length = strlen(text) + 1;
error.text.data = strdup(text);
if (error.text.data) {
if (!krb5_mk_error(context, &error, &outbuf)) {
(void)krb5_write_message(context, &fd, &outbuf);
krb5_free_data_contents(context, &outbuf);
}
free(error.text.data);
}
}
static void
update_last_prop_file(char *hostname, char *file_name)
{
char *file_last_prop;
int fd;
static char last_prop[] = ".last_prop";
if (asprintf(&file_last_prop, "%s.%s%s", file_name, hostname,
last_prop) < 0) {
com_err(progname, ENOMEM,
_("while allocating filename for update_last_prop_file"));
return;
}
fd = THREEPARAMOPEN(file_last_prop, O_WRONLY | O_CREAT | O_TRUNC, 0600);
if (fd < 0) {
com_err(progname, errno, _("while creating 'last_prop' file, '%s'"),
file_last_prop);
free(file_last_prop);
return;
}
write(fd, "", 1);
free(file_last_prop);
close(fd);
}