-/*
+/*
Unix SMB/CIFS implementation.
Kerberos utility functions for GENSEC
-
+
Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
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; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
-
+
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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "auth/kerberos/kerberos.h"
#include "auth/credentials/credentials.h"
#include "auth/credentials/credentials_krb5.h"
+#include "auth/kerberos/kerberos_credentials.h"
+#include "auth/kerberos/kerberos_util.h"
struct principal_container {
struct smb_krb5_context *smb_krb5_context;
krb5_principal principal;
+ const char *string_form; /* Optional */
};
-static int free_principal(struct principal_container *pc)
+static krb5_error_code free_principal(struct principal_container *pc)
{
/* current heimdal - 0.6.3, which we need anyway, fixes segfaults here */
krb5_free_principal(pc->smb_krb5_context->krb5_context, pc->principal);
return 0;
}
-static krb5_error_code salt_principal_from_credentials(TALLOC_CTX *parent_ctx,
- struct cli_credentials *machine_account,
- struct smb_krb5_context *smb_krb5_context,
- krb5_principal *salt_princ)
+
+static krb5_error_code parse_principal(TALLOC_CTX *parent_ctx,
+ const char *princ_string,
+ struct smb_krb5_context *smb_krb5_context,
+ krb5_principal *princ,
+ const char **error_string)
{
- krb5_error_code ret;
- char *machine_username;
- char *salt_body;
- char *lower_realm;
- const char *salt_principal;
- struct principal_container *mem_ctx = talloc(parent_ctx, struct principal_container);
+ int ret;
+ struct principal_container *mem_ctx;
+ if (princ_string == NULL) {
+ *princ = NULL;
+ return 0;
+ }
+
+ /*
+ * Start with talloc(), talloc_reference() and only then call
+ * krb5_parse_name(). If any of them fails, the cleanup code is simpler.
+ */
+ mem_ctx = talloc(parent_ctx, struct principal_container);
if (!mem_ctx) {
+ (*error_string) = error_message(ENOMEM);
return ENOMEM;
}
- salt_principal = cli_credentials_get_salt_principal(machine_account);
- if (salt_principal) {
- ret = krb5_parse_name(smb_krb5_context->krb5_context, salt_principal, salt_princ);
- } else {
- machine_username = talloc_strdup(mem_ctx, cli_credentials_get_username(machine_account));
-
- if (!machine_username) {
- talloc_free(mem_ctx);
- return ENOMEM;
- }
-
- if (machine_username[strlen(machine_username)-1] == '$') {
- machine_username[strlen(machine_username)-1] = '\0';
- }
- lower_realm = strlower_talloc(mem_ctx, cli_credentials_get_realm(machine_account));
- if (!lower_realm) {
- talloc_free(mem_ctx);
- return ENOMEM;
- }
-
- salt_body = talloc_asprintf(mem_ctx, "%s.%s", machine_username,
- lower_realm);
- if (!salt_body) {
- talloc_free(mem_ctx);
+ mem_ctx->smb_krb5_context = talloc_reference(mem_ctx,
+ smb_krb5_context);
+ if (mem_ctx->smb_krb5_context == NULL) {
+ (*error_string) = error_message(ENOMEM);
+ talloc_free(mem_ctx);
return ENOMEM;
- }
-
- ret = krb5_make_principal(smb_krb5_context->krb5_context, salt_princ,
- cli_credentials_get_realm(machine_account),
- "host", salt_body, NULL);
- }
-
- if (ret == 0) {
- /* This song-and-dance effectivly puts the principal
- * into talloc, so we can't loose it. */
- mem_ctx->smb_krb5_context = talloc_reference(mem_ctx, smb_krb5_context);
- mem_ctx->principal = *salt_princ;
- talloc_set_destructor(mem_ctx, free_principal);
}
- return ret;
+
+ ret = krb5_parse_name(smb_krb5_context->krb5_context,
+ princ_string, princ);
+
+ if (ret) {
+ (*error_string) = smb_get_krb5_error_message(
+ smb_krb5_context->krb5_context,
+ ret, parent_ctx);
+ talloc_free(mem_ctx);
+ return ret;
+ }
+
+ /* This song-and-dance effectively puts the principal
+ * into talloc, so we can't lose it. */
+ mem_ctx->principal = *princ;
+ talloc_set_destructor(mem_ctx, free_principal);
+ return 0;
}
/* Obtain the principal set on this context. Requires a
* the library routines. The returned princ is placed in the talloc
* system by means of a destructor (do *not* free). */
-krb5_error_code principal_from_credentials(TALLOC_CTX *parent_ctx,
- struct cli_credentials *credentials,
- struct smb_krb5_context *smb_krb5_context,
- krb5_principal *princ)
+krb5_error_code principal_from_credentials(TALLOC_CTX *parent_ctx,
+ struct cli_credentials *credentials,
+ struct smb_krb5_context *smb_krb5_context,
+ krb5_principal *princ,
+ enum credentials_obtained *obtained,
+ const char **error_string)
{
krb5_error_code ret;
const char *princ_string;
- struct principal_container *mem_ctx = talloc(parent_ctx, struct principal_container);
+ TALLOC_CTX *mem_ctx = talloc_new(parent_ctx);
+ *obtained = CRED_UNINITIALISED;
+
if (!mem_ctx) {
+ (*error_string) = error_message(ENOMEM);
return ENOMEM;
}
-
- princ_string = cli_credentials_get_principal(credentials, mem_ctx);
-
- /* A NULL here has meaning, as the gssapi server case will
- * then use the principal from the client */
+ princ_string = cli_credentials_get_principal_and_obtained(credentials,
+ mem_ctx,
+ obtained);
if (!princ_string) {
- talloc_free(mem_ctx);
- princ = NULL;
+ *princ = NULL;
return 0;
}
- ret = krb5_parse_name(smb_krb5_context->krb5_context,
- princ_string, princ);
+ ret = parse_principal(parent_ctx, princ_string,
+ smb_krb5_context, princ, error_string);
+ talloc_free(mem_ctx);
+ return ret;
+}
+
+/* Obtain the principal set on this context. Requires a
+ * smb_krb5_context because we are doing krb5 principal parsing with
+ * the library routines. The returned princ is placed in the talloc
+ * system by means of a destructor (do *not* free). */
- if (ret == 0) {
- /* This song-and-dance effectivly puts the principal
- * into talloc, so we can't loose it. */
- mem_ctx->smb_krb5_context = talloc_reference(mem_ctx, smb_krb5_context);
- mem_ctx->principal = *princ;
- talloc_set_destructor(mem_ctx, free_principal);
+static krb5_error_code impersonate_principal_from_credentials(
+ TALLOC_CTX *parent_ctx,
+ struct cli_credentials *credentials,
+ struct smb_krb5_context *smb_krb5_context,
+ krb5_principal *princ,
+ const char **error_string)
+{
+ return parse_principal(parent_ctx,
+ cli_credentials_get_impersonate_principal(credentials),
+ smb_krb5_context, princ, error_string);
+}
+
+krb5_error_code smb_krb5_create_principals_array(TALLOC_CTX *mem_ctx,
+ krb5_context context,
+ const char *account_name,
+ const char *realm,
+ uint32_t num_spns,
+ const char *spns[],
+ uint32_t *pnum_principals,
+ krb5_principal **pprincipals,
+ const char **error_string)
+{
+ krb5_error_code code;
+ TALLOC_CTX *tmp_ctx;
+ uint32_t num_principals = 0;
+ krb5_principal *principals;
+ uint32_t i;
+
+ tmp_ctx = talloc_new(mem_ctx);
+ if (tmp_ctx == NULL) {
+ *error_string = "Cannot allocate tmp_ctx";
+ return ENOMEM;
}
- return ret;
+
+ if (realm == NULL) {
+ *error_string = "Cannot create principal without a realm";
+ code = EINVAL;
+ goto done;
+ }
+
+ if (account_name == NULL && (num_spns == 0 || spns == NULL)) {
+ *error_string = "Cannot create principal without an account or SPN";
+ code = EINVAL;
+ goto done;
+ }
+
+ if (account_name != NULL && account_name[0] != '\0') {
+ num_principals++;
+ }
+ num_principals += num_spns;
+
+ principals = talloc_zero_array(tmp_ctx,
+ krb5_principal,
+ num_principals);
+ if (principals == NULL) {
+ *error_string = "Cannot allocate principals";
+ code = ENOMEM;
+ goto done;
+ }
+
+ for (i = 0; i < num_spns; i++) {
+ code = krb5_parse_name(context, spns[i], &(principals[i]));
+ if (code != 0) {
+ *error_string = smb_get_krb5_error_message(context,
+ code,
+ mem_ctx);
+ goto done;
+ }
+ }
+
+ if (account_name != NULL && account_name[0] != '\0') {
+ code = smb_krb5_make_principal(context,
+ &(principals[i]),
+ realm,
+ account_name,
+ NULL);
+ if (code != 0) {
+ *error_string = smb_get_krb5_error_message(context,
+ code,
+ mem_ctx);
+ goto done;
+ }
+ }
+
+ if (pnum_principals != NULL) {
+ *pnum_principals = num_principals;
+
+ if (pprincipals != NULL) {
+ *pprincipals = talloc_steal(mem_ctx, principals);
+ }
+ }
+
+ code = 0;
+done:
+ talloc_free(tmp_ctx);
+ return code;
}
/**
* Return a freshly allocated ccache (destroyed by destructor on child
- * of parent_ctx), for a given set of client credentials
+ * of parent_ctx), for a given set of client credentials
*/
krb5_error_code kinit_to_ccache(TALLOC_CTX *parent_ctx,
struct cli_credentials *credentials,
struct smb_krb5_context *smb_krb5_context,
- krb5_ccache ccache)
+ struct loadparm_context *lp_ctx,
+ struct tevent_context *event_ctx,
+ krb5_ccache ccache,
+ enum credentials_obtained *obtained,
+ const char **error_string)
{
krb5_error_code ret;
const char *password;
+ const char *self_service;
+ const char *target_service;
time_t kdc_time = 0;
krb5_principal princ;
+ krb5_principal impersonate_principal;
int tries;
TALLOC_CTX *mem_ctx = talloc_new(parent_ctx);
+ krb5_get_init_creds_opt *krb_options;
+ struct cli_credentials *fast_creds;
if (!mem_ctx) {
+ (*error_string) = strerror(ENOMEM);
return ENOMEM;
}
- ret = principal_from_credentials(mem_ctx, credentials, smb_krb5_context, &princ);
+ ret = principal_from_credentials(mem_ctx, credentials, smb_krb5_context, &princ, obtained, error_string);
if (ret) {
talloc_free(mem_ctx);
return ret;
}
+ if (princ == NULL) {
+ (*error_string) = talloc_asprintf(credentials, "principal, username or realm was not specified in the credentials");
+ talloc_free(mem_ctx);
+ return KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
+ }
+
+ ret = impersonate_principal_from_credentials(mem_ctx, credentials, smb_krb5_context, &impersonate_principal, error_string);
+ if (ret) {
+ talloc_free(mem_ctx);
+ return ret;
+ }
+
+ self_service = cli_credentials_get_self_service(credentials);
+ target_service = cli_credentials_get_target_service(credentials);
+
password = cli_credentials_get_password(credentials);
+ /* setup the krb5 options we want */
+ if ((ret = krb5_get_init_creds_opt_alloc(smb_krb5_context->krb5_context, &krb_options))) {
+ (*error_string) = talloc_asprintf(credentials, "krb5_get_init_creds_opt_alloc failed (%s)\n",
+ smb_get_krb5_error_message(smb_krb5_context->krb5_context,
+ ret, mem_ctx));
+ talloc_free(mem_ctx);
+ return ret;
+ }
+
+#ifdef SAMBA4_USES_HEIMDAL /* Disable for now MIT reads defaults when needed */
+ /* get the defaults */
+ krb5_get_init_creds_opt_set_default_flags(smb_krb5_context->krb5_context, NULL, NULL, krb_options);
+#endif
+ /* set if we want a forwardable ticket */
+ switch (cli_credentials_get_krb_forwardable(credentials)) {
+ case CRED_AUTO_KRB_FORWARDABLE:
+ break;
+ case CRED_NO_KRB_FORWARDABLE:
+ krb5_get_init_creds_opt_set_forwardable(krb_options, FALSE);
+ break;
+ case CRED_FORCE_KRB_FORWARDABLE:
+ krb5_get_init_creds_opt_set_forwardable(krb_options, TRUE);
+ break;
+ }
+
+#ifdef SAMBA4_USES_HEIMDAL /* FIXME: MIT does not have this yet */
+ /*
+ * In order to work against windows KDCs even if we use
+ * the netbios domain name as realm, we need to add the following
+ * flags:
+ * KRB5_INIT_CREDS_NO_C_CANON_CHECK;
+ * KRB5_INIT_CREDS_NO_C_NO_EKU_CHECK;
+ *
+ * On MIT: Set pkinit_eku_checking to none
+ */
+ krb5_get_init_creds_opt_set_win2k(smb_krb5_context->krb5_context,
+ krb_options, true);
+ krb5_get_init_creds_opt_set_canonicalize(smb_krb5_context->krb5_context,
+ krb_options, true);
+#else /* MIT */
+ krb5_get_init_creds_opt_set_canonicalize(krb_options, true);
+#endif
+
+ fast_creds = cli_credentials_get_krb5_fast_armor_credentials(credentials);
+
+ if (fast_creds != NULL) {
+#ifdef HAVE_KRB5_GET_INIT_CREDS_OPT_SET_FAST_CCACHE
+ struct ccache_container *fast_ccc = NULL;
+ const char *fast_error_string = NULL;
+ ret = cli_credentials_get_ccache(fast_creds, event_ctx, lp_ctx, &fast_ccc, &fast_error_string);
+ if (ret != 0) {
+ (*error_string) = talloc_asprintf(credentials,
+ "Obtaining the Kerberos FAST armor credentials failed: %s\n",
+ fast_error_string);
+ return ret;
+ }
+ krb5_get_init_creds_opt_set_fast_ccache(smb_krb5_context->krb5_context,
+ krb_options,
+ fast_ccc->ccache);
+#else
+ *error_string = talloc_strdup(credentials,
+ "Using Kerberos FAST "
+ "armor credentials not possible "
+ "with this Kerberos library. "
+ "Modern MIT or Samba's embedded "
+ "Heimdal required");
+ return EINVAL;
+#endif
+ }
+
+#ifdef HAVE_KRB5_GET_INIT_CREDS_OPT_SET_FAST_FLAGS
+ {
+ bool require_fast;
+ /*
+ * This ensures that if FAST was required, but no armor
+ * credentials cache was specified, we proceed with (eg)
+ * anonymous PKINIT
+ */
+ require_fast = cli_credentials_get_krb5_require_fast_armor(credentials);
+ if (require_fast) {
+ krb5_get_init_creds_opt_set_fast_flags(smb_krb5_context->krb5_context,
+ krb_options,
+ KRB5_FAST_REQUIRED);
+ }
+ }
+#endif
+
tries = 2;
while (tries--) {
+#ifdef SAMBA4_USES_HEIMDAL
+ struct tevent_context *previous_ev;
+ /* Do this every time, in case we have weird recursive issues here */
+ ret = smb_krb5_context_set_event_ctx(smb_krb5_context, event_ctx, &previous_ev);
+ if (ret) {
+ talloc_free(mem_ctx);
+ krb5_get_init_creds_opt_free(smb_krb5_context->krb5_context, krb_options);
+ return ret;
+ }
+#endif
if (password) {
- ret = kerberos_kinit_password_cc(smb_krb5_context->krb5_context, ccache,
- princ,
- password, NULL, &kdc_time);
+ if (impersonate_principal) {
+ ret = smb_krb5_kinit_s4u2_ccache(smb_krb5_context->krb5_context,
+ ccache,
+ princ,
+ password,
+ impersonate_principal,
+ self_service,
+ target_service,
+ krb_options,
+ NULL,
+ &kdc_time);
+ } else {
+ ret = smb_krb5_kinit_password_ccache(smb_krb5_context->krb5_context,
+ ccache,
+ princ,
+ password,
+ target_service,
+ krb_options,
+ NULL,
+ &kdc_time);
+ }
+ } else if (impersonate_principal) {
+ talloc_free(mem_ctx);
+ (*error_string) = "INTERNAL error: Cannot impersonate principal with just a keyblock. A password must be specified in the credentials";
+ krb5_get_init_creds_opt_free(smb_krb5_context->krb5_context, krb_options);
+#ifdef SAMBA4_USES_HEIMDAL
+ smb_krb5_context_remove_event_ctx(smb_krb5_context, previous_ev, event_ctx);
+#endif
+ return EINVAL;
} else {
/* No password available, try to use a keyblock instead */
-
+
krb5_keyblock keyblock;
const struct samr_Password *mach_pwd;
mach_pwd = cli_credentials_get_nt_hash(credentials, mem_ctx);
if (!mach_pwd) {
talloc_free(mem_ctx);
- DEBUG(1, ("kinit_to_ccache: No password available for kinit\n"));
+ (*error_string) = "kinit_to_ccache: No password available for kinit\n";
+ krb5_get_init_creds_opt_free(smb_krb5_context->krb5_context, krb_options);
+#ifdef SAMBA4_USES_HEIMDAL
+ smb_krb5_context_remove_event_ctx(smb_krb5_context, previous_ev, event_ctx);
+#endif
return EINVAL;
}
- ret = krb5_keyblock_init(smb_krb5_context->krb5_context,
- ETYPE_ARCFOUR_HMAC_MD5,
- mach_pwd->hash, sizeof(mach_pwd->hash),
+ ret = smb_krb5_keyblock_init_contents(smb_krb5_context->krb5_context,
+ ENCTYPE_ARCFOUR_HMAC,
+ mach_pwd->hash, sizeof(mach_pwd->hash),
&keyblock);
-
+
if (ret == 0) {
- ret = kerberos_kinit_keyblock_cc(smb_krb5_context->krb5_context, ccache,
- princ,
- &keyblock, NULL, &kdc_time);
+ ret = smb_krb5_kinit_keyblock_ccache(smb_krb5_context->krb5_context,
+ ccache,
+ princ,
+ &keyblock,
+ target_service,
+ krb_options,
+ NULL,
+ &kdc_time);
krb5_free_keyblock_contents(smb_krb5_context->krb5_context, &keyblock);
}
}
+#ifdef SAMBA4_USES_HEIMDAL
+ smb_krb5_context_remove_event_ctx(smb_krb5_context, previous_ev, event_ctx);
+#endif
+
if (ret == KRB5KRB_AP_ERR_SKEW || ret == KRB5_KDCREP_SKEW) {
/* Perhaps we have been given an invalid skew, so try again without it */
time_t t = time(NULL);
}
}
+ krb5_get_init_creds_opt_free(smb_krb5_context->krb5_context, krb_options);
+
if (ret == KRB5KRB_AP_ERR_SKEW || ret == KRB5_KDCREP_SKEW) {
- DEBUG(1,("kinit for %s failed (%s)\n",
- cli_credentials_get_principal(credentials, mem_ctx),
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
+ (*error_string) = talloc_asprintf(credentials, "kinit for %s failed (%s)\n",
+ cli_credentials_get_principal(credentials, mem_ctx),
+ smb_get_krb5_error_message(smb_krb5_context->krb5_context,
+ ret, mem_ctx));
talloc_free(mem_ctx);
return ret;
}
DEBUG(4,("Advancing clock by %d seconds to cope with clock skew\n", time_offset));
krb5_set_real_time(smb_krb5_context->krb5_context, t + time_offset + 1, 0);
}
-
+
if (ret == KRB5KDC_ERR_PREAUTH_FAILED && cli_credentials_wrong_password(credentials)) {
ret = kinit_to_ccache(parent_ctx,
credentials,
smb_krb5_context,
- ccache);
+ lp_ctx,
+ event_ctx,
+ ccache, obtained,
+ error_string);
}
- if (ret) {
- DEBUG(1,("kinit for %s failed (%s)\n",
- cli_credentials_get_principal(credentials, mem_ctx),
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- talloc_free(mem_ctx);
- return ret;
- }
- return 0;
-}
-
-static int free_keytab(struct keytab_container *ktc)
-{
- krb5_kt_close(ktc->smb_krb5_context->krb5_context, ktc->keytab);
- return 0;
-}
-
-int smb_krb5_open_keytab(TALLOC_CTX *mem_ctx,
- struct smb_krb5_context *smb_krb5_context,
- const char *keytab_name, struct keytab_container **ktc)
-{
- krb5_keytab keytab;
- int ret;
- ret = krb5_kt_resolve(smb_krb5_context->krb5_context, keytab_name, &keytab);
if (ret) {
- DEBUG(1,("failed to open krb5 keytab: %s\n",
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
+ (*error_string) = talloc_asprintf(credentials, "kinit for %s failed (%s)\n",
+ cli_credentials_get_principal(credentials, mem_ctx),
+ smb_get_krb5_error_message(smb_krb5_context->krb5_context,
+ ret, mem_ctx));
+ talloc_free(mem_ctx);
return ret;
}
- *ktc = talloc(mem_ctx, struct keytab_container);
- if (!*ktc) {
- return ENOMEM;
- }
+ DEBUG(10,("kinit for %s succeeded\n",
+ cli_credentials_get_principal(credentials, mem_ctx)));
- (*ktc)->smb_krb5_context = talloc_reference(*ktc, smb_krb5_context);
- (*ktc)->keytab = keytab;
- talloc_set_destructor(*ktc, free_keytab);
+ talloc_free(mem_ctx);
return 0;
}
-static krb5_error_code keytab_add_keys(TALLOC_CTX *parent_ctx,
- const char *princ_string,
- krb5_principal princ,
- krb5_principal salt_princ,
- int kvno,
- const char *password_s,
- struct smb_krb5_context *smb_krb5_context,
- const char **enctype_strings,
- krb5_keytab keytab)
+static krb5_error_code free_keytab_container(struct keytab_container *ktc)
{
- int i;
- krb5_error_code ret;
- krb5_data password;
- TALLOC_CTX *mem_ctx = talloc_new(parent_ctx);
- if (!mem_ctx) {
- return ENOMEM;
- }
-
- password.data = discard_const_p(char *, password_s);
- password.length = strlen(password_s);
-
- for (i=0; enctype_strings[i]; i++) {
- krb5_keytab_entry entry;
- krb5_enctype enctype;
- ret = krb5_string_to_enctype(smb_krb5_context->krb5_context, enctype_strings[i], &enctype);
- if (ret != 0) {
- DEBUG(1, ("Failed to interpret %s as a krb5 encryption type: %s\n",
- enctype_strings[i],
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- talloc_free(mem_ctx);
- return ret;
- }
- ret = create_kerberos_key_from_string(smb_krb5_context->krb5_context,
- salt_princ, &password, &entry.keyblock, enctype);
- if (ret != 0) {
- talloc_free(mem_ctx);
- return ret;
- }
-
- entry.principal = princ;
- entry.vno = kvno;
- ret = krb5_kt_add_entry(smb_krb5_context->krb5_context, keytab, &entry);
- if (ret != 0) {
- DEBUG(1, ("Failed to add %s entry for %s(kvno %d) to keytab: %s\n",
- enctype_strings[i],
- princ_string,
- kvno,
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- talloc_free(mem_ctx);
- krb5_free_keyblock_contents(smb_krb5_context->krb5_context, &entry.keyblock);
- return ret;
- }
-
- DEBUG(5, ("Added %s(kvno %d) to keytab (%s)\n",
- princ_string, kvno,
- enctype_strings[i]));
-
- krb5_free_keyblock_contents(smb_krb5_context->krb5_context, &entry.keyblock);
- }
- talloc_free(mem_ctx);
- return 0;
+ return krb5_kt_close(ktc->smb_krb5_context->krb5_context, ktc->keytab);
}
-static int create_keytab(TALLOC_CTX *parent_ctx,
- struct cli_credentials *machine_account,
- struct smb_krb5_context *smb_krb5_context,
- const char **enctype_strings,
- krb5_keytab keytab,
- BOOL add_old)
+krb5_error_code smb_krb5_get_keytab_container(TALLOC_CTX *mem_ctx,
+ struct smb_krb5_context *smb_krb5_context,
+ krb5_keytab opt_keytab,
+ const char *keytab_name,
+ struct keytab_container **ktc)
{
+ krb5_keytab keytab;
krb5_error_code ret;
- const char *password_s;
- const char *old_secret;
- int kvno;
- krb5_principal salt_princ;
- krb5_principal princ;
- const char *princ_string;
- TALLOC_CTX *mem_ctx = talloc_new(parent_ctx);
- if (!mem_ctx) {
+ /*
+ * Start with talloc(), talloc_reference() and only then call
+ * krb5_kt_resolve(). If any of them fails, the cleanup code is simpler.
+ */
+ *ktc = talloc(mem_ctx, struct keytab_container);
+ if (!*ktc) {
return ENOMEM;
}
- princ_string = cli_credentials_get_principal(machine_account, mem_ctx);
- /* Get the principal we will store the new keytab entries under */
- ret = principal_from_credentials(mem_ctx, machine_account, smb_krb5_context, &princ);
- if (ret) {
- DEBUG(1,("create_keytab: makeing krb5 principal failed (%s)\n",
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- talloc_free(mem_ctx);
- return ret;
- }
-
- /* The salt used to generate these entries may be different however, fetch that */
- ret = salt_principal_from_credentials(mem_ctx, machine_account,
- smb_krb5_context,
- &salt_princ);
- if (ret) {
- DEBUG(1,("create_keytab: makeing salt principal failed (%s)\n",
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- talloc_free(mem_ctx);
- return ret;
+ (*ktc)->smb_krb5_context = talloc_reference(*ktc, smb_krb5_context);
+ if ((*ktc)->smb_krb5_context == NULL) {
+ TALLOC_FREE(*ktc);
+ return ENOMEM;
}
- /* Finally, do the dance to get the password to put in the entry */
- password_s = cli_credentials_get_password(machine_account);
- if (!password_s) {
- krb5_keytab_entry entry;
- const struct samr_Password *mach_pwd;
-
- if (!str_list_check(enctype_strings, "arcfour-hmac-md5")) {
- DEBUG(1, ("Asked to create keytab, but with only an NT hash supplied, "
- "but not listing arcfour-hmac-md5 as an enc type to include in the keytab!\n"));
- talloc_free(mem_ctx);
- return EINVAL;
- }
-
- /* If we don't have the plaintext password, try for
- * the MD4 password hash */
- mach_pwd = cli_credentials_get_nt_hash(machine_account, mem_ctx);
- if (!mach_pwd) {
- /* OK, nothing to do here */
- talloc_free(mem_ctx);
- return 0;
- }
- ret = krb5_keyblock_init(smb_krb5_context->krb5_context,
- ETYPE_ARCFOUR_HMAC_MD5,
- mach_pwd->hash, sizeof(mach_pwd->hash),
- &entry.keyblock);
- if (ret) {
- DEBUG(1, ("create_keytab: krb5_keyblock_init failed: %s\n",
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- talloc_free(mem_ctx);
- return ret;
- }
-
- entry.principal = princ;
- entry.vno = cli_credentials_get_kvno(machine_account);
- ret = krb5_kt_add_entry(smb_krb5_context->krb5_context, keytab, &entry);
+ if (opt_keytab) {
+ keytab = opt_keytab;
+ } else {
+ ret = krb5_kt_resolve(smb_krb5_context->krb5_context,
+ keytab_name, &keytab);
if (ret) {
- DEBUG(1, ("Failed to add ARCFOUR_HMAC (only) entry for %s to keytab: %s",
- cli_credentials_get_principal(machine_account, mem_ctx),
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- talloc_free(mem_ctx);
- krb5_free_keyblock_contents(smb_krb5_context->krb5_context, &entry.keyblock);
+ DEBUG(1,("failed to open krb5 keytab: %s\n",
+ smb_get_krb5_error_message(
+ smb_krb5_context->krb5_context,
+ ret, mem_ctx)));
+ TALLOC_FREE(*ktc);
return ret;
}
-
- DEBUG(5, ("Added %s(kvno %d) to keytab (arcfour-hmac-md5)\n",
- cli_credentials_get_principal(machine_account, mem_ctx),
- cli_credentials_get_kvno(machine_account)));
-
- krb5_free_keyblock_contents(smb_krb5_context->krb5_context, &entry.keyblock);
-
- /* Can't go any further, we only have this one key */
- talloc_free(mem_ctx);
- return 0;
- }
-
- kvno = cli_credentials_get_kvno(machine_account);
- /* good, we actually have the real plaintext */
- ret = keytab_add_keys(mem_ctx, princ_string, princ, salt_princ,
- kvno, password_s, smb_krb5_context,
- enctype_strings, keytab);
- if (!ret) {
- talloc_free(mem_ctx);
- return ret;
- }
-
- if (!add_old || kvno == 0) {
- talloc_free(mem_ctx);
- return 0;
}
- old_secret = cli_credentials_get_old_password(machine_account);
- if (!old_secret) {
- talloc_free(mem_ctx);
- return 0;
- }
-
- ret = keytab_add_keys(mem_ctx, princ_string, princ, salt_princ,
- kvno - 1, old_secret, smb_krb5_context,
- enctype_strings, keytab);
- if (!ret) {
- talloc_free(mem_ctx);
- return ret;
- }
+ (*ktc)->keytab = keytab;
+ (*ktc)->password_based = false;
+ talloc_set_destructor(*ktc, free_keytab_container);
- talloc_free(mem_ctx);
return 0;
}
-
/*
- * Walk the keytab, looking for entries of this principal name, with KVNO other than current kvno -1.
+ * Walk the keytab, looking for entries of this principal name,
+ * with KVNO other than current kvno -1.
*
- * These entries are now stale, we only keep the current, and previous entries around.
+ * These entries are now stale,
+ * we only keep the current and previous entries around.
*
* Inspired by the code in Samba3 for 'use kerberos keytab'.
- *
*/
-
-static krb5_error_code remove_old_entries(TALLOC_CTX *parent_ctx,
- struct cli_credentials *machine_account,
- struct smb_krb5_context *smb_krb5_context,
- krb5_keytab keytab, BOOL *found_previous)
+krb5_error_code smb_krb5_remove_obsolete_keytab_entries(TALLOC_CTX *mem_ctx,
+ krb5_context context,
+ krb5_keytab keytab,
+ uint32_t num_principals,
+ krb5_principal *principals,
+ krb5_kvno kvno,
+ bool *found_previous,
+ const char **error_string)
{
- krb5_error_code ret, ret2;
+ TALLOC_CTX *tmp_ctx;
+ krb5_error_code code;
krb5_kt_cursor cursor;
- krb5_principal princ;
- int kvno;
- TALLOC_CTX *mem_ctx = talloc_new(parent_ctx);
- const char *princ_string;
- if (!mem_ctx) {
- return ENOMEM;
- }
-
- *found_previous = False;
- princ_string = cli_credentials_get_principal(machine_account, mem_ctx);
- /* Get the principal we will store the new keytab entries under */
- ret = principal_from_credentials(mem_ctx, machine_account, smb_krb5_context, &princ);
- if (ret) {
- DEBUG(1,("update_keytab: makeing krb5 principal failed (%s)\n",
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- talloc_free(mem_ctx);
- return ret;
+ tmp_ctx = talloc_new(mem_ctx);
+ if (tmp_ctx == NULL) {
+ *error_string = "Cannot allocate tmp_ctx";
+ return ENOMEM;
}
- kvno = cli_credentials_get_kvno(machine_account);
+ *found_previous = true;
- /* for each entry in the keytab */
- ret = krb5_kt_start_seq_get(smb_krb5_context->krb5_context, keytab, &cursor);
- switch (ret) {
+ code = krb5_kt_start_seq_get(context, keytab, &cursor);
+ switch (code) {
case 0:
break;
+#ifdef HEIM_ERR_OPNOTSUPP
case HEIM_ERR_OPNOTSUPP:
+#endif
case ENOENT:
case KRB5_KT_END:
/* no point enumerating if there isn't anything here */
- talloc_free(mem_ctx);
- return 0;
+ code = 0;
+ goto done;
default:
- DEBUG(1,("failed to open keytab for read of old entries: %s\n",
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- talloc_free(mem_ctx);
- return ret;
+ *error_string = talloc_asprintf(mem_ctx,
+ "failed to open keytab for read of old entries: %s\n",
+ smb_get_krb5_error_message(context, code, tmp_ctx));
+ goto done;
}
- while (!ret) {
+ do {
+ krb5_kvno old_kvno = kvno - 1;
krb5_keytab_entry entry;
- ret = krb5_kt_next_entry(smb_krb5_context->krb5_context, keytab, &entry, &cursor);
- if (ret) {
+ bool matched = false;
+ uint32_t i;
+
+ code = krb5_kt_next_entry(context, keytab, &entry, &cursor);
+ if (code) {
break;
}
- /* if it matches our principal */
- if (!krb5_kt_compare(smb_krb5_context->krb5_context, &entry, princ, 0, 0)) {
- /* Free the entry, it wasn't the one we were looking for anyway */
- krb5_kt_free_entry(smb_krb5_context->krb5_context, &entry);
+
+ for (i = 0; i < num_principals; i++) {
+ krb5_boolean ok;
+
+ ok = smb_krb5_kt_compare(context,
+ &entry,
+ principals[i],
+ 0,
+ 0);
+ if (ok) {
+ matched = true;
+ break;
+ }
+ }
+
+ if (!matched) {
+ /*
+ * Free the entry, it wasn't the one we were looking
+ * for anyway
+ */
+ krb5_kt_free_entry(context, &entry);
+ /* Make sure we do not double free */
+ ZERO_STRUCT(entry);
continue;
}
- /* delete it, if it is not kvno -1 */
- if (entry.vno != (kvno - 1 )) {
+ /*
+ * Delete it, if it is not kvno - 1.
+ *
+ * Some keytab files store the kvno only in 8bits. Limit the
+ * compare to 8bits, so that we don't miss old keys and delete
+ * them.
+ */
+ if ((entry.vno & 0xff) != (old_kvno & 0xff)) {
+ krb5_error_code rc;
+
/* Release the enumeration. We are going to
* have to start this from the top again,
* because deletes during enumeration may not
- * always be consistant.
+ * always be consistent.
*
* Also, the enumeration locks a FILE: keytab
*/
-
- krb5_kt_end_seq_get(smb_krb5_context->krb5_context, keytab, &cursor);
+ krb5_kt_end_seq_get(context, keytab, &cursor);
+
+ code = krb5_kt_remove_entry(context, keytab, &entry);
+ krb5_kt_free_entry(context, &entry);
- ret = krb5_kt_remove_entry(smb_krb5_context->krb5_context, keytab, &entry);
- krb5_kt_free_entry(smb_krb5_context->krb5_context, &entry);
+ /* Make sure we do not double free */
+ ZERO_STRUCT(entry);
/* Deleted: Restart from the top */
- ret2 = krb5_kt_start_seq_get(smb_krb5_context->krb5_context, keytab, &cursor);
- if (ret2) {
- krb5_kt_free_entry(smb_krb5_context->krb5_context, &entry);
- DEBUG(1,("failed to restart enumeration of keytab: %s\n",
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
-
- talloc_free(mem_ctx);
- return ret2;
+ rc = krb5_kt_start_seq_get(context, keytab, &cursor);
+ if (rc != 0) {
+ krb5_kt_free_entry(context, &entry);
+
+ /* Make sure we do not double free */
+ ZERO_STRUCT(entry);
+
+ DEBUG(1, ("failed to restart enumeration of keytab: %s\n",
+ smb_get_krb5_error_message(context,
+ code,
+ tmp_ctx)));
+
+ talloc_free(tmp_ctx);
+ return rc;
}
- if (ret) {
+ if (code != 0) {
break;
}
-
+
} else {
- *found_previous = True;
+ *found_previous = true;
}
-
+
/* Free the entry, we don't need it any more */
- krb5_kt_free_entry(smb_krb5_context->krb5_context, &entry);
-
-
- }
- krb5_kt_end_seq_get(smb_krb5_context->krb5_context, keytab, &cursor);
+ krb5_kt_free_entry(context, &entry);
+ /* Make sure we do not double free */
+ ZERO_STRUCT(entry);
+ } while (code == 0);
+
+ krb5_kt_end_seq_get(context, keytab, &cursor);
- switch (ret) {
+ switch (code) {
case 0:
break;
case ENOENT:
case KRB5_KT_END:
- ret = 0;
break;
default:
- DEBUG(1,("failed in deleting old entries for principal: %s: %s\n",
- princ_string,
- smb_get_krb5_error_message(smb_krb5_context->krb5_context,
- ret, mem_ctx)));
- }
- talloc_free(mem_ctx);
- return ret;
+ *error_string = talloc_asprintf(mem_ctx,
+ "failed in deleting old entries for principal: %s\n",
+ smb_get_krb5_error_message(context,
+ code,
+ tmp_ctx));
+ goto done;
+ }
+
+ code = 0;
+done:
+ talloc_free(tmp_ctx);
+ return code;
}
-int smb_krb5_update_keytab(TALLOC_CTX *parent_ctx,
- struct cli_credentials *machine_account,
- struct smb_krb5_context *smb_krb5_context,
- const char **enctype_strings,
- struct keytab_container *keytab_container)
+/*
+ * Walk the keytab, looking for entries of this principal name,
+ * with KVNO and key equal
+ *
+ * These entries do not need to be replaced, so we want to tell the caller not to add them again
+ *
+ * Inspired by the code in Samba3 for 'use kerberos keytab'.
+ */
+krb5_error_code smb_krb5_is_exact_entry_in_keytab(TALLOC_CTX *mem_ctx,
+ krb5_context context,
+ krb5_keytab keytab,
+ krb5_keytab_entry *to_match,
+ bool *found,
+ const char **error_string)
{
- krb5_error_code ret;
- BOOL found_previous;
- TALLOC_CTX *mem_ctx = talloc_new(parent_ctx);
- if (!mem_ctx) {
+ TALLOC_CTX *tmp_ctx;
+ krb5_error_code code;
+ krb5_kt_cursor cursor;
+
+ tmp_ctx = talloc_new(mem_ctx);
+ if (tmp_ctx == NULL) {
+ *error_string = "Cannot allocate tmp_ctx";
return ENOMEM;
}
- ret = remove_old_entries(mem_ctx, machine_account,
- smb_krb5_context, keytab_container->keytab, &found_previous);
- if (ret != 0) {
- talloc_free(mem_ctx);
- return ret;
- }
-
- /* Create a new keytab. If during the cleanout we found
- * entires for kvno -1, then don't try and duplicate them.
- * Otherwise, add kvno, and kvno -1 */
-
- ret = create_keytab(mem_ctx, machine_account, smb_krb5_context,
- enctype_strings,
- keytab_container->keytab,
- found_previous ? False : True);
- talloc_free(mem_ctx);
- return ret;
-}
+ *found = false;
-_PUBLIC_ int smb_krb5_create_memory_keytab(TALLOC_CTX *parent_ctx,
- struct cli_credentials *machine_account,
- struct smb_krb5_context *smb_krb5_context,
- const char **enctype_strings,
- struct keytab_container **keytab_container)
-{
- krb5_error_code ret;
- TALLOC_CTX *mem_ctx = talloc_new(parent_ctx);
- const char *rand_string;
- const char *keytab_name;
- if (!mem_ctx) {
- return ENOMEM;
+ code = krb5_kt_start_seq_get(context, keytab, &cursor);
+ switch (code) {
+ case 0:
+ break;
+#ifdef HEIM_ERR_OPNOTSUPP
+ case HEIM_ERR_OPNOTSUPP:
+#endif
+ case ENOENT:
+ case KRB5_KT_END:
+ /* no point enumerating if there isn't anything here */
+ code = 0;
+ goto done;
+ default:
+ *error_string = talloc_asprintf(mem_ctx,
+ "failed to open keytab for read of existing entries: %s\n",
+ smb_get_krb5_error_message(context, code, tmp_ctx));
+ goto done;
}
-
- *keytab_container = talloc(mem_ctx, struct keytab_container);
- rand_string = generate_random_str(mem_ctx, 16);
- if (!rand_string) {
- talloc_free(mem_ctx);
- return ENOMEM;
- }
+ do {
+ krb5_keytab_entry entry;
+ bool matched = false;
+ krb5_boolean ok;
- keytab_name = talloc_asprintf(mem_ctx, "MEMORY:%s",
- rand_string);
- if (!keytab_name) {
- talloc_free(mem_ctx);
- return ENOMEM;
- }
+ code = krb5_kt_next_entry(context, keytab, &entry, &cursor);
+ if (code) {
+ break;
+ }
- ret = smb_krb5_open_keytab(mem_ctx, smb_krb5_context, keytab_name, keytab_container);
- if (ret) {
- return ret;
- }
+ ok = smb_krb5_kt_compare(context,
+ &entry,
+ to_match->principal,
+ to_match->vno,
+ KRB5_KEY_TYPE(KRB5_KT_KEY(to_match)));
+ if (ok) {
+ /* This is not a security check, constant time is not required */
+ if ((KRB5_KEY_LENGTH(KRB5_KT_KEY(&entry)) == KRB5_KEY_LENGTH(KRB5_KT_KEY(to_match)))
+ && memcmp(KRB5_KEY_DATA(KRB5_KT_KEY(&entry)), KRB5_KEY_DATA(KRB5_KT_KEY(to_match)),
+ KRB5_KEY_LENGTH(KRB5_KT_KEY(&entry))) == 0) {
+ matched = true;
+ }
+ }
- ret = smb_krb5_update_keytab(mem_ctx, machine_account, smb_krb5_context, enctype_strings, *keytab_container);
- if (ret == 0) {
- talloc_steal(parent_ctx, *keytab_container);
- } else {
- *keytab_container = NULL;
- }
- talloc_free(mem_ctx);
- return ret;
-}
+ /* Free the entry, we don't need it any more */
+ krb5_kt_free_entry(context, &entry);
+ /* Make sure we do not double free */
+ ZERO_STRUCT(entry);
+ if (matched) {
+ *found = true;
+ break;
+ }
+ } while (code == 0);
+
+ krb5_kt_end_seq_get(context, keytab, &cursor);
+ switch (code) {
+ case 0:
+ break;
+ case ENOENT:
+ case KRB5_KT_END:
+ break;
+ default:
+ *error_string = talloc_asprintf(mem_ctx,
+ "failed in checking old entries for principal: %s\n",
+ smb_get_krb5_error_message(context,
+ code,
+ tmp_ctx));
+ goto done;
+ }
+
+ code = 0;
+done:
+ talloc_free(tmp_ctx);
+ return code;
+}
git.samba.org / samba.git / blobdiff