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/* Authors: Rob Crittenden <rcritten@redhat.com>
*
* Copyright (C) 2009 Red Hat
* see file 'COPYING' for use and warranty information
*
* 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; version 2 only
*
* 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
*/
#define _GNU_SOURCE
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <krb5.h>
#include <popt.h>
#include <errno.h>
int
remove_principal(krb5_context context, krb5_keytab ktid, const char *principal, int debug)
{
krb5_error_code krberr;
krb5_keytab_entry entry, entry2;
int rval = 0;
int removed = 0;
memset(&entry, 0, sizeof(entry));
krberr = krb5_parse_name(context, principal, &entry.principal);
if (krberr) {
fprintf(stderr, "Unable to parse principal name\n");
if (debug)
fprintf(stderr, "krb5_parse_name %d: %s\n", krberr, error_message(krberr));
rval = 4;
goto done;
}
/* Loop through the keytab and remove all entries with this principal name
* irrespective of the encryption type. A failure to find one after the
* first means we're done.
*/
fprintf(stderr, "Removing principal %s\n", principal);
while (1) {
memset(&entry2, 0, sizeof(entry2));
krberr = krb5_kt_get_entry(context, ktid,
entry.principal,
0,
0,
&entry2);
if (krberr) {
if (removed > 0)
/* not found but we've removed some, we're done */
break;
if (krberr == ENOENT) {
fprintf(stderr, "Failed to open keytab\n");
rval = 3;
goto done;
}
fprintf(stderr, "principal not found\n");
if (debug)
fprintf(stderr, "krb5_kt_get_entry %d: %s\n", krberr, error_message(krberr));
rval = 5;
break;
}
krberr = krb5_kt_remove_entry(context, ktid, &entry2);
if (krberr) {
fprintf(stderr, "Unable to remove entry\n");
if (debug) {
fprintf(stdout, "kvno %d\n", entry2.vno);
fprintf(stderr, "krb5_kt_remove_entry %d: %s\n", krberr, error_message(krberr));
}
rval = 6;
break;
}
krb5_free_keytab_entry_contents(context, &entry2);
removed++;
}
if (entry2.principal)
krb5_free_keytab_entry_contents(context, &entry2);
done:
return rval;
}
int
remove_realm(krb5_context context, krb5_keytab ktid, const char *realm, int debug)
{
krb5_error_code krberr;
krb5_keytab_entry entry;
krb5_kt_cursor kt_cursor;
char * entry_princ_s = NULL;
int rval = 0;
krberr = krb5_kt_start_seq_get(context, ktid, &kt_cursor);
memset(&entry, 0, sizeof(entry));
while (krb5_kt_next_entry(context, ktid, &entry, &kt_cursor) == 0) {
krberr = krb5_unparse_name(context, entry.principal, &entry_princ_s);
if (krberr) {
fprintf(stderr, "Unable to parse principal\n");
if (debug) {
fprintf(stderr, "krb5_unparse_name %d: %s\n", krberr, error_message(krberr));
}
rval = 4;
goto done;
}
/* keytab entries are locked when looping. Temporarily suspend
* the looping. */
krb5_kt_end_seq_get(context, ktid, &kt_cursor);
if (strstr(entry_princ_s, realm) != NULL) {
rval = remove_principal(context, ktid, entry_princ_s, debug);
if (rval != 0)
goto done;
/* Have to reset the cursor */
krberr = krb5_kt_start_seq_get(context, ktid, &kt_cursor);
}
}
done:
return rval;
}
int
main(int argc, char **argv)
{
krb5_context context;
krb5_error_code krberr;
krb5_keytab ktid;
char * ktname;
char * atrealm;
poptContext pc;
static const char *keytab = NULL;
static const char *principal = NULL;
static const char *realm = NULL;
int debug = 0;
int ret, rval;
struct poptOption options[] = {
{ "debug", 'd', POPT_ARG_NONE, &debug, 0, "Print debugging information", "Debugging output" },
{ "principal", 'p', POPT_ARG_STRING, &principal, 0, "The principal to get a keytab for (ex: ftp/ftp.example.com@EXAMPLE.COM)", "Kerberos Service Principal Name" },
{ "keytab", 'k', POPT_ARG_STRING, &keytab, 0, "File were to store the keytab information", "Keytab File Name" },
{ "realm", 'r', POPT_ARG_STRING, &realm, 0, "Remove all principals in this realm", "Realm name" },
{ NULL, 0, POPT_ARG_NONE, NULL, 0, NULL, NULL }
};
memset(&ktid, 0, sizeof(ktid));
krberr = krb5_init_context(&context);
if (krberr) {
fprintf(stderr, "Kerberos context initialization failed\n");
exit(1);
}
pc = poptGetContext("ipa-rmkeytab", argc, (const char **)argv, options, 0);
ret = poptGetNextOpt(pc);
if (ret != -1 || (!principal && !realm) || !keytab) {
poptPrintUsage(pc, stderr, 0);
rval = 1;
goto cleanup;
}
ret = asprintf(&ktname, "WRFILE:%s", keytab);
if (ret == -1) {
rval = 2;
goto cleanup;
}
/* The remove_realm function just does a substring match. Ensure that
* the string we pass in looks like a realm.
*/
if (realm) {
if (realm[0] != '@')
ret = asprintf(&atrealm, "@%s", realm);
if (ret == -1) {
rval = 2;
goto cleanup;
}
else
atrealm = strcpy(atrealm, realm);
}
krberr = krb5_kt_resolve(context, ktname, &ktid);
if (krberr) {
fprintf(stderr, "Failed to open keytab '%s'\n", keytab);
rval = 3;
goto cleanup;
}
if (principal)
rval = remove_principal(context, ktid, principal, debug);
else if (realm)
rval = remove_realm(context, ktid, atrealm, debug);
cleanup:
if (rval == 0 || rval > 3) {
krberr = krb5_kt_close(context, ktid);
if (krberr) {
fprintf(stderr, "Closing keytab failed\n");
if (debug)
fprintf(stderr, "krb5_kt_close %d: %s\n", krberr, error_message(krberr));
}
}
krb5_free_context(context);
poptFreeContext(pc);
return rval;
}
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