s4-credentials Add explicit event context handling to Kerberos calls (only)

By setting the event context to use for this operation (only) onto
the krb5_context just before we call that operation, we can try
and emulate the specification of an event context to the actual send_to_kdc()

This eliminates the specification of an event context to many other
cli_credentials calls, and the last use of event_context_find()

Special care is taken to restore the event context in the event of
nesting in the send_to_kdc function.

Andrew Bartlett

14 files changed, 187 insertions, 87 deletions

diff --git a/source4/auth/credentials/credentials.c b/source4/auth/credentials/credentials.c
index 2bd041450c..21ee987852 100644
--- a/source4/auth/credentials/credentials.c
+++ b/source4/auth/credentials/credentials.c
@@ -727,7 +727,7 @@ _PUBLIC_ void cli_credentials_guess(struct cli_credentials *cred,
 	}
 	
 	if (cli_credentials_get_kerberos_state(cred) != CRED_DONT_USE_KERBEROS) {
-		cli_credentials_set_ccache(cred, event_context_find(cred), lp_ctx, NULL, CRED_GUESS_FILE,
+		cli_credentials_set_ccache(cred, lp_ctx, NULL, CRED_GUESS_FILE,
 					   &error_string);
 	}
 }
diff --git a/source4/auth/credentials/credentials.h b/source4/auth/credentials/credentials.h
index a468624b1f..0b0de59752 100644
--- a/source4/auth/credentials/credentials.h
+++ b/source4/auth/credentials/credentials.h
@@ -168,7 +168,6 @@ NTSTATUS cli_credentials_get_ntlm_response(struct cli_credentials *cred, TALLOC_
 const char *cli_credentials_get_realm(struct cli_credentials *cred);
 const char *cli_credentials_get_username(struct cli_credentials *cred);
 int cli_credentials_get_krb5_context(struct cli_credentials *cred, 
-				     struct tevent_context *event_ctx,
 				     struct loadparm_context *lp_ctx,
 				     struct smb_krb5_context **smb_krb5_context);
 int cli_credentials_get_ccache(struct cli_credentials *cred, 
@@ -182,7 +181,6 @@ int cli_credentials_get_named_ccache(struct cli_credentials *cred,
 				     char *ccache_name,
 				     struct ccache_container **ccc, const char **error_string);
 int cli_credentials_get_keytab(struct cli_credentials *cred, 
-			       struct tevent_context *event_ctx,
 			       struct loadparm_context *lp_ctx,
 			       struct keytab_container **_ktc);
 const char *cli_credentials_get_domain(struct cli_credentials *cred);
@@ -193,7 +191,6 @@ void cli_credentials_set_conf(struct cli_credentials *cred,
 			      struct loadparm_context *lp_ctx);
 const char *cli_credentials_get_principal(struct cli_credentials *cred, TALLOC_CTX *mem_ctx);
 int cli_credentials_get_server_gss_creds(struct cli_credentials *cred, 
-					 struct tevent_context *event_ctx,
 					 struct loadparm_context *lp_ctx,
 					 struct gssapi_creds_container **_gcc);
 int cli_credentials_get_client_gss_creds(struct cli_credentials *cred, 
@@ -238,7 +235,6 @@ void cli_credentials_set_netlogon_creds(struct cli_credentials *cred,
 NTSTATUS cli_credentials_set_krb5_context(struct cli_credentials *cred, 
 					  struct smb_krb5_context *smb_krb5_context);
 NTSTATUS cli_credentials_set_stored_principal(struct cli_credentials *cred,
-					      struct tevent_context *event_ctx,
 					      struct loadparm_context *lp_ctx,
 					      const char *serviceprincipal);
 NTSTATUS cli_credentials_set_machine_account(struct cli_credentials *cred,
@@ -265,14 +261,12 @@ bool cli_credentials_set_ntlm_response(struct cli_credentials *cred,
 				       const DATA_BLOB *nt_response, 
 				       enum credentials_obtained obtained);
 int cli_credentials_set_keytab_name(struct cli_credentials *cred, 
-				    struct tevent_context *event_ctx,
 				    struct loadparm_context *lp_ctx,
 				    const char *keytab_name, 
 				    enum credentials_obtained obtained);
 void cli_credentials_set_gensec_features(struct cli_credentials *creds, uint32_t gensec_features);
 uint32_t cli_credentials_get_gensec_features(struct cli_credentials *creds);
 int cli_credentials_set_ccache(struct cli_credentials *cred, 
-			       struct tevent_context *event_ctx,
 			       struct loadparm_context *lp_ctx,
 			       const char *name, 
 			       enum credentials_obtained obtained,
@@ -291,7 +285,6 @@ const char *cli_credentials_get_target_service(struct cli_credentials *cred);
 enum credentials_use_kerberos cli_credentials_get_kerberos_state(struct cli_credentials *creds);
 enum credentials_krb_forwardable cli_credentials_get_krb_forwardable(struct cli_credentials *creds);
 NTSTATUS cli_credentials_set_secrets(struct cli_credentials *cred, 
-				     struct tevent_context *event_ctx,
 				     struct loadparm_context *lp_ctx,
 				     struct ldb_context *ldb,
 				     const char *base,
diff --git a/source4/auth/credentials/credentials_krb5.c b/source4/auth/credentials/credentials_krb5.c
index c678b80f87..fb4b440281 100644
--- a/source4/auth/credentials/credentials_krb5.c
+++ b/source4/auth/credentials/credentials_krb5.c
@@ -32,7 +32,6 @@
 #include "param/param.h"
 
 _PUBLIC_ int cli_credentials_get_krb5_context(struct cli_credentials *cred, 
-					      struct tevent_context *event_ctx,
 				     struct loadparm_context *lp_ctx,
 				     struct smb_krb5_context **smb_krb5_context) 
 {
@@ -42,7 +41,7 @@ _PUBLIC_ int cli_credentials_get_krb5_context(struct cli_credentials *cred,
 		return 0;
 	}
 
-	ret = smb_krb5_init_context(cred, event_ctx, lp_ctx,
+	ret = smb_krb5_init_context(cred, NULL, lp_ctx,
 				    &cred->smb_krb5_context);
 	if (ret) {
 		cred->smb_krb5_context = NULL;
@@ -126,7 +125,6 @@ static int free_dccache(struct ccache_container *ccc) {
 }
 
 _PUBLIC_ int cli_credentials_set_ccache(struct cli_credentials *cred, 
-					struct tevent_context *event_ctx,
 					struct loadparm_context *lp_ctx,
 					const char *name,
 					enum credentials_obtained obtained,
@@ -145,7 +143,7 @@ _PUBLIC_ int cli_credentials_set_ccache(struct cli_credentials *cred,
 		return ENOMEM;
 	}
 
-	ret = cli_credentials_get_krb5_context(cred, event_ctx, lp_ctx,
+	ret = cli_credentials_get_krb5_context(cred, lp_ctx,
 					       &ccc->smb_krb5_context);
 	if (ret) {
 		(*error_string) = error_message(ret);
@@ -204,7 +202,6 @@ _PUBLIC_ int cli_credentials_set_ccache(struct cli_credentials *cred,
 
 
 static int cli_credentials_new_ccache(struct cli_credentials *cred, 
-				      struct tevent_context *event_ctx,
 				      struct loadparm_context *lp_ctx,
 				      char *ccache_name,
 				      struct ccache_container **_ccc,
@@ -217,7 +214,7 @@ static int cli_credentials_new_ccache(struct cli_credentials *cred,
 		return ENOMEM;
 	}
 
-	ret = cli_credentials_get_krb5_context(cred, event_ctx, lp_ctx,
+	ret = cli_credentials_get_krb5_context(cred, lp_ctx,
 					       &ccc->smb_krb5_context);
 	if (ret) {
 		talloc_free(ccc);
@@ -294,12 +291,12 @@ _PUBLIC_ int cli_credentials_get_named_ccache(struct cli_credentials *cred,
 		return EINVAL;
 	}
 
-	ret = cli_credentials_new_ccache(cred, event_ctx, lp_ctx, ccache_name, ccc, error_string);
+	ret = cli_credentials_new_ccache(cred, lp_ctx, ccache_name, ccc, error_string);
 	if (ret) {
 		return ret;
 	}
 
-	ret = kinit_to_ccache(cred, cred, (*ccc)->smb_krb5_context, (*ccc)->ccache, &obtained, error_string);
+	ret = kinit_to_ccache(cred, cred, (*ccc)->smb_krb5_context, event_ctx, (*ccc)->ccache, &obtained, error_string);
 	if (ret) {
 		return ret;
 	}
@@ -529,7 +526,6 @@ _PUBLIC_ int cli_credentials_get_client_gss_creds(struct cli_credentials *cred,
 */
 
  int cli_credentials_set_client_gss_creds(struct cli_credentials *cred, 
-					  struct tevent_context *event_ctx,
 					  struct loadparm_context *lp_ctx,
 					  gss_cred_id_t gssapi_cred,
 					  enum credentials_obtained obtained,
@@ -549,7 +545,7 @@ _PUBLIC_ int cli_credentials_get_client_gss_creds(struct cli_credentials *cred,
 		return ENOMEM;
 	}
 
-	ret = cli_credentials_new_ccache(cred, event_ctx, lp_ctx, NULL, &ccc, error_string);
+	ret = cli_credentials_new_ccache(cred, lp_ctx, NULL, &ccc, error_string);
 	if (ret != 0) {
 		return ret;
 	}
@@ -589,9 +585,8 @@ _PUBLIC_ int cli_credentials_get_client_gss_creds(struct cli_credentials *cred,
  * it will be generated from the password.
  */
 _PUBLIC_ int cli_credentials_get_keytab(struct cli_credentials *cred, 
-					struct tevent_context *event_ctx,
-			       struct loadparm_context *lp_ctx,
-			       struct keytab_container **_ktc)
+					struct loadparm_context *lp_ctx,
+					struct keytab_container **_ktc)
 {
 	krb5_error_code ret;
 	struct keytab_container *ktc;
@@ -608,7 +603,7 @@ _PUBLIC_ int cli_credentials_get_keytab(struct cli_credentials *cred,
 		return EINVAL;
 	}
 
-	ret = cli_credentials_get_krb5_context(cred, event_ctx, lp_ctx,
+	ret = cli_credentials_get_krb5_context(cred, lp_ctx,
 					       &smb_krb5_context);
 	if (ret) {
 		return ret;
@@ -640,10 +635,9 @@ _PUBLIC_ int cli_credentials_get_keytab(struct cli_credentials *cred,
  * FILE:/etc/krb5.keytab), open it and attach it */
 
 _PUBLIC_ int cli_credentials_set_keytab_name(struct cli_credentials *cred, 
-					     struct tevent_context *event_ctx,
-				    struct loadparm_context *lp_ctx,
-				    const char *keytab_name, 
-				    enum credentials_obtained obtained) 
+					     struct loadparm_context *lp_ctx,
+					     const char *keytab_name,
+					     enum credentials_obtained obtained)
 {
 	krb5_error_code ret;
 	struct keytab_container *ktc;
@@ -654,7 +648,7 @@ _PUBLIC_ int cli_credentials_set_keytab_name(struct cli_credentials *cred,
 		return 0;
 	}
 
-	ret = cli_credentials_get_krb5_context(cred, event_ctx, lp_ctx, &smb_krb5_context);
+	ret = cli_credentials_get_krb5_context(cred, lp_ctx, &smb_krb5_context);
 	if (ret) {
 		return ret;
 	}
@@ -682,9 +676,8 @@ _PUBLIC_ int cli_credentials_set_keytab_name(struct cli_credentials *cred,
 /* Get server gss credentials (in gsskrb5, this means the keytab) */
 
 _PUBLIC_ int cli_credentials_get_server_gss_creds(struct cli_credentials *cred, 
-						  struct tevent_context *event_ctx,
-					 struct loadparm_context *lp_ctx,
-					 struct gssapi_creds_container **_gcc) 
+						  struct loadparm_context *lp_ctx,
+						  struct gssapi_creds_container **_gcc)
 {
 	int ret = 0;
 	OM_uint32 maj_stat, min_stat;
@@ -701,7 +694,7 @@ _PUBLIC_ int cli_credentials_get_server_gss_creds(struct cli_credentials *cred,
 		return ENOMEM;
 	}
 
-	ret = cli_credentials_get_krb5_context(cred, event_ctx, lp_ctx, &smb_krb5_context);
+	ret = cli_credentials_get_krb5_context(cred, lp_ctx, &smb_krb5_context);
 	if (ret) {
 		return ret;
 	}
@@ -720,7 +713,7 @@ _PUBLIC_ int cli_credentials_get_server_gss_creds(struct cli_credentials *cred,
 		return 0;
 	}
 
-	ret = cli_credentials_get_keytab(cred, event_ctx, lp_ctx, &ktc);
+	ret = cli_credentials_get_keytab(cred, lp_ctx, &ktc);
 	if (ret) {
 		DEBUG(1, ("Failed to get keytab for GSSAPI server: %s\n", error_message(ret)));
 		return ret;
diff --git a/source4/auth/credentials/credentials_krb5.h b/source4/auth/credentials/credentials_krb5.h
index 1630b210db..36bf03d5eb 100644
--- a/source4/auth/credentials/credentials_krb5.h
+++ b/source4/auth/credentials/credentials_krb5.h
@@ -33,7 +33,6 @@ struct gssapi_creds_container {
 
 /* Manually prototyped here to avoid needing gss headers in most callers */
 int cli_credentials_set_client_gss_creds(struct cli_credentials *cred, 
-					 struct tevent_context *event_ctx,
 					 struct loadparm_context *lp_ctx,
 					 gss_cred_id_t gssapi_cred,
 					 enum credentials_obtained obtained,
diff --git a/source4/auth/credentials/credentials_secrets.c b/source4/auth/credentials/credentials_secrets.c
index 9ffc39c0c3..0f30dc5e1b 100644
--- a/source4/auth/credentials/credentials_secrets.c
+++ b/source4/auth/credentials/credentials_secrets.c
@@ -42,7 +42,6 @@
  * @retval NTSTATUS error detailing any failure
  */
 _PUBLIC_ NTSTATUS cli_credentials_set_secrets(struct cli_credentials *cred, 
-					      struct tevent_context *event_ctx,
 					      struct loadparm_context *lp_ctx,
 					      struct ldb_context *ldb,
 					      const char *base,
@@ -180,7 +179,7 @@ _PUBLIC_ NTSTATUS cli_credentials_set_secrets(struct cli_credentials *cred,
 	 * (chewing CPU time) from the password */
 	keytab = keytab_name_from_msg(cred, ldb, msg);
 	if (keytab) {
-		cli_credentials_set_keytab_name(cred, event_ctx, lp_ctx, keytab, CRED_SPECIFIED);
+		cli_credentials_set_keytab_name(cred, lp_ctx, keytab, CRED_SPECIFIED);
 		talloc_free(keytab);
 	}
 	talloc_free(mem_ctx);
@@ -205,9 +204,9 @@ _PUBLIC_ NTSTATUS cli_credentials_set_machine_account(struct cli_credentials *cr
 	 * any more */
 	cred->machine_account_pending = false;
 	filter = talloc_asprintf(cred, SECRETS_PRIMARY_DOMAIN_FILTER, 
-				       cli_credentials_get_domain(cred));
-	status = cli_credentials_set_secrets(cred, event_context_find(cred), lp_ctx, NULL,
-					   SECRETS_PRIMARY_DOMAIN_DN,
+				 cli_credentials_get_domain(cred));
+	status = cli_credentials_set_secrets(cred, lp_ctx, NULL,
+					     SECRETS_PRIMARY_DOMAIN_DN,
 					     filter, &error_string);
 	if (!NT_STATUS_IS_OK(status)) {
 		DEBUG(1, ("Could not find machine account in secrets database: %s: %s", nt_errstr(status), error_string));
@@ -223,7 +222,6 @@ _PUBLIC_ NTSTATUS cli_credentials_set_machine_account(struct cli_credentials *cr
  * @retval NTSTATUS error detailing any failure
  */
 NTSTATUS cli_credentials_set_krbtgt(struct cli_credentials *cred,
-			            struct tevent_context *event_ctx,
 				    struct loadparm_context *lp_ctx)
 {
 	NTSTATUS status;
@@ -236,7 +234,7 @@ NTSTATUS cli_credentials_set_krbtgt(struct cli_credentials *cred,
 	filter = talloc_asprintf(cred, SECRETS_KRBTGT_SEARCH,
 				       cli_credentials_get_realm(cred),
 				       cli_credentials_get_domain(cred));
-	status = cli_credentials_set_secrets(cred, event_ctx, lp_ctx, NULL,
+	status = cli_credentials_set_secrets(cred, lp_ctx, NULL,
 					     SECRETS_PRINCIPALS_DN,
 					     filter, &error_string);
 	if (!NT_STATUS_IS_OK(status)) {
@@ -253,7 +251,6 @@ NTSTATUS cli_credentials_set_krbtgt(struct cli_credentials *cred,
  * @retval NTSTATUS error detailing any failure
  */
 _PUBLIC_ NTSTATUS cli_credentials_set_stored_principal(struct cli_credentials *cred,
-						       struct tevent_context *event_ctx,
 					      struct loadparm_context *lp_ctx,
 					      const char *serviceprincipal)
 {
@@ -268,7 +265,7 @@ _PUBLIC_ NTSTATUS cli_credentials_set_stored_principal(struct cli_credentials *c
 				 cli_credentials_get_realm(cred),
 				 cli_credentials_get_domain(cred),
 				 serviceprincipal);
-	status = cli_credentials_set_secrets(cred, event_ctx, lp_ctx, NULL,
+	status = cli_credentials_set_secrets(cred, lp_ctx, NULL,
 					     SECRETS_PRINCIPALS_DN, filter,
 					     &error_string);
 	if (!NT_STATUS_IS_OK(status)) {
diff --git a/source4/auth/gensec/gensec_gssapi.c b/source4/auth/gensec/gensec_gssapi.c
index 51d59d9f21..4729ed6062 100644
--- a/source4/auth/gensec/gensec_gssapi.c
+++ b/source4/auth/gensec/gensec_gssapi.c
@@ -147,7 +147,6 @@ static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
 {
 	struct gensec_gssapi_state *gensec_gssapi_state;
 	krb5_error_code ret;
-	struct gsskrb5_send_to_kdc send_to_kdc;
 	const char *realm;
 
 	gensec_gssapi_state = talloc(gensec_security, struct gensec_gssapi_state);
@@ -209,7 +208,7 @@ static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
 	gensec_gssapi_state->pac = data_blob(NULL, 0);
 
 	ret = smb_krb5_init_context(gensec_gssapi_state,
-				    gensec_security->event_ctx,
+				    NULL,
 				    gensec_security->settings->lp_ctx,
 				    &gensec_gssapi_state->smb_krb5_context);
 	if (ret) {
@@ -237,16 +236,6 @@ static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
 
 	talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destructor);
 
-	send_to_kdc.func = smb_krb5_send_and_recv_func;
-	send_to_kdc.ptr = gensec_security->event_ctx;
-
-	ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
-	if (ret) {
-		DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
-		talloc_free(gensec_gssapi_state);
-		return NT_STATUS_INTERNAL_ERROR;
-	}
-
 	realm = lpcfg_realm(gensec_security->settings->lp_ctx);
 	if (realm != NULL) {
 		ret = gsskrb5_set_default_realm(realm);
@@ -290,7 +279,6 @@ static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_securi
 		return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 	} else {
 		ret = cli_credentials_get_server_gss_creds(machine_account, 
-							   gensec_security->event_ctx, 
 							   gensec_security->settings->lp_ctx, &gcc);
 		if (ret) {
 			DEBUG(1, ("Aquiring acceptor credentials failed: %s\n", 
@@ -469,6 +457,17 @@ static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 		switch (gensec_security->gensec_role) {
 		case GENSEC_CLIENT:
 		{
+			struct gsskrb5_send_to_kdc send_to_kdc;
+			krb5_error_code ret;
+			send_to_kdc.func = smb_krb5_send_and_recv_func;
+			send_to_kdc.ptr = gensec_security->event_ctx;
+
+			min_stat = gsskrb5_set_send_to_kdc(&send_to_kdc);
+			if (min_stat) {
+				DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
+				return NT_STATUS_INTERNAL_ERROR;
+			}
+
 			maj_stat = gss_init_sec_context(&min_stat, 
 							gensec_gssapi_state->client_cred->creds,
 							&gensec_gssapi_state->gssapi_context, 
@@ -485,6 +484,16 @@ static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 			if (gss_oid_p) {
 				gensec_gssapi_state->gss_oid = gss_oid_p;
 			}
+
+			send_to_kdc.func = smb_krb5_send_and_recv_func;
+			send_to_kdc.ptr = NULL;
+
+			ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
+			if (ret) {
+				DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
+				return NT_STATUS_INTERNAL_ERROR;
+			}
+
 			break;
 		}
 		case GENSEC_SERVER:
@@ -1369,7 +1378,6 @@ static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_securi
 		cli_credentials_set_anonymous(session_info->credentials);
 		
 		ret = cli_credentials_set_client_gss_creds(session_info->credentials, 
-							   gensec_security->event_ctx,
 							   gensec_security->settings->lp_ctx,
 							   gensec_gssapi_state->delegated_cred_handle,
 							   CRED_SPECIFIED, &error_string);
diff --git a/source4/auth/gensec/gensec_krb5.c b/source4/auth/gensec/gensec_krb5.c
index a0d880f5b2..345ef361ed 100644
--- a/source4/auth/gensec/gensec_krb5.c
+++ b/source4/auth/gensec/gensec_krb5.c
@@ -119,7 +119,6 @@ static NTSTATUS gensec_krb5_start(struct gensec_security *gensec_security, bool
 	talloc_set_destructor(gensec_krb5_state, gensec_krb5_destroy); 
 
 	if (cli_credentials_get_krb5_context(creds, 
-					     gensec_security->event_ctx, 
 					     gensec_security->settings->lp_ctx, &gensec_krb5_state->smb_krb5_context)) {
 		talloc_free(gensec_krb5_state);
 		return NT_STATUS_INTERNAL_ERROR;
@@ -240,6 +239,7 @@ static NTSTATUS gensec_krb5_common_client_start(struct gensec_security *gensec_s
 	const char *error_string;
 	const char *principal;
 	krb5_data in_data;
+	struct tevent_context *previous_ev;
 
 	hostname = gensec_get_target_hostname(gensec_security);
 	if (!hostname) {
@@ -299,6 +299,12 @@ static NTSTATUS gensec_krb5_common_client_start(struct gensec_security *gensec_s
 	}
 	in_data.length = 0;
 	
+	/* Do this every time, in case we have weird recursive issues here */
+	ret = smb_krb5_context_set_event_ctx(gensec_krb5_state->smb_krb5_context, gensec_security->event_ctx, &previous_ev);
+	if (ret != 0) {
+		DEBUG(1, ("gensec_krb5_start: Setting event context failed\n"));
+		return NT_STATUS_NO_MEMORY;
+	}
 	if (principal) {
 		krb5_principal target_principal;
 		ret = krb5_parse_name(gensec_krb5_state->smb_krb5_context->krb5_context, principal,
@@ -322,6 +328,9 @@ static NTSTATUS gensec_krb5_common_client_start(struct gensec_security *gensec_s
 				  &in_data, ccache_container->ccache, 
 				  &gensec_krb5_state->enc_ticket);
 	}
+
+	smb_krb5_context_remove_event_ctx(gensec_krb5_state->smb_krb5_context, previous_ev, gensec_security->event_ctx);
+
 	switch (ret) {
 	case 0:
 		return NT_STATUS_OK;
@@ -488,7 +497,6 @@ static NTSTATUS gensec_krb5_update(struct gensec_security *gensec_security,
 
 		/* Grab the keytab, however generated */
 		ret = cli_credentials_get_keytab(gensec_get_credentials(gensec_security), 
-					         gensec_security->event_ctx, 
 						 gensec_security->settings->lp_ctx, &keytab);
 		if (ret) {
 			return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
diff --git a/source4/auth/kerberos/kerberos_credentials.h b/source4/auth/kerberos/kerberos_credentials.h
index 55227752e3..e94b88e005 100644
--- a/source4/auth/kerberos/kerberos_credentials.h
+++ b/source4/auth/kerberos/kerberos_credentials.h
@@ -21,8 +21,9 @@
 */
 
 krb5_error_code kinit_to_ccache(TALLOC_CTX *parent_ctx,
-				 struct cli_credentials *credentials,
-				 struct smb_krb5_context *smb_krb5_context,
-				 krb5_ccache ccache,
-				 enum credentials_obtained *obtained,
-				 const char **error_string);
+				struct cli_credentials *credentials,
+				struct smb_krb5_context *smb_krb5_context,
+				struct tevent_context *event_ctx,
+				krb5_ccache ccache,
+				enum credentials_obtained *obtained,
+				const char **error_string);
diff --git a/source4/auth/kerberos/kerberos_util.c b/source4/auth/kerberos/kerberos_util.c
index 3020e978bd..c5079123ef 100644
--- a/source4/auth/kerberos/kerberos_util.c
+++ b/source4/auth/kerberos/kerberos_util.c
@@ -332,6 +332,7 @@ krb5_error_code principal_from_credentials(TALLOC_CTX *parent_ctx,
  krb5_error_code kinit_to_ccache(TALLOC_CTX *parent_ctx,
 				 struct cli_credentials *credentials,
 				 struct smb_krb5_context *smb_krb5_context,
+				 struct tevent_context *event_ctx,
 				 krb5_ccache ccache,
 				 enum credentials_obtained *obtained,
 				 const char **error_string)
@@ -392,6 +393,13 @@ krb5_error_code principal_from_credentials(TALLOC_CTX *parent_ctx,
 
 	tries = 2;
 	while (tries--) {
+		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);
+			return ret;
+		}
 		if (password) {
 			ret = kerberos_kinit_password_cc(smb_krb5_context->krb5_context, ccache, 
 							 princ, password,
@@ -399,6 +407,7 @@ krb5_error_code principal_from_credentials(TALLOC_CTX *parent_ctx,
 							 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";
 			return EINVAL;
 		} else {
@@ -411,6 +420,7 @@ krb5_error_code principal_from_credentials(TALLOC_CTX *parent_ctx,
 				talloc_free(mem_ctx);
 				(*error_string) = "kinit_to_ccache: No password available for kinit\n";
 				krb5_get_init_creds_opt_free(smb_krb5_context->krb5_context, krb_options);
+				smb_krb5_context_remove_event_ctx(smb_krb5_context, previous_ev, event_ctx);
 				return EINVAL;
 			}
 			ret = krb5_keyblock_init(smb_krb5_context->krb5_context,
@@ -427,6 +437,8 @@ krb5_error_code principal_from_credentials(TALLOC_CTX *parent_ctx,
 			}
 		}
 
+		smb_krb5_context_remove_event_ctx(smb_krb5_context, previous_ev, event_ctx);
+
 		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);
@@ -460,6 +472,7 @@ krb5_error_code principal_from_credentials(TALLOC_CTX *parent_ctx,
 		ret = kinit_to_ccache(parent_ctx,
 				      credentials,
 				      smb_krb5_context,
+				      event_ctx,
 				      ccache, obtained,
 				      error_string);
 	}
diff --git a/source4/auth/kerberos/krb5_init_context.c b/source4/auth/kerberos/krb5_init_context.c
index aebc79e767..54f27b0860 100644
--- a/source4/auth/kerberos/krb5_init_context.c
+++ b/source4/auth/kerberos/krb5_init_context.c
@@ -211,18 +211,37 @@ krb5_error_code smb_krb5_send_and_recv_func(krb5_context context,
 	struct addrinfo *ai, *a;
 	struct smb_krb5_socket *smb_krb5;
 
-	struct tevent_context *ev = talloc_get_type(data, struct tevent_context);
+	DATA_BLOB send_blob;
 
-	DATA_BLOB send_blob = data_blob_const(send_buf->data, send_buf->length);
+	struct tevent_context *ev;
+	TALLOC_CTX *tmp_ctx = talloc_new(NULL);
+	if (!tmp_ctx) {
+		return ENOMEM;
+	}
+
+	if (!data) {
+		/* If no event context was available, then create one for this loop */
+		ev = tevent_context_init(tmp_ctx);
+		if (!ev) {
+			talloc_free(tmp_ctx);
+			return ENOMEM;
+		}
+	} else {
+		ev = talloc_get_type_abort(data, struct tevent_context);
+	}
+
+	send_blob = data_blob_const(send_buf->data, send_buf->length);
 
 	ret = krb5_krbhst_get_addrinfo(context, hi, &ai);
 	if (ret) {
+		talloc_free(tmp_ctx);
 		return ret;
 	}
 
 	for (a = ai; a; a = ai->ai_next) {
-		smb_krb5 = talloc(NULL, struct smb_krb5_socket);
+		smb_krb5 = talloc(tmp_ctx, struct smb_krb5_socket);
 		if (!smb_krb5) {
+			talloc_free(tmp_ctx);
 			return ENOMEM;
 		}
 		smb_krb5->hi = hi;
@@ -237,7 +256,7 @@ krb5_error_code smb_krb5_send_and_recv_func(krb5_context context,
 			break;
 #endif
 		default:
-			talloc_free(smb_krb5);
+			talloc_free(tmp_ctx);
 			return EINVAL;
 		}
 
@@ -250,7 +269,7 @@ krb5_error_code smb_krb5_send_and_recv_func(krb5_context context,
 			status = socket_create(name, SOCKET_TYPE_STREAM, &smb_krb5->sock, 0);
 			break;
 		case KRB5_KRBHST_HTTP:
-			talloc_free(smb_krb5);
+			talloc_free(tmp_ctx);
 			return EINVAL;
 		}
 		if (!NT_STATUS_IS_OK(status)) {
@@ -319,14 +338,28 @@ krb5_error_code smb_krb5_send_and_recv_func(krb5_context context,
 			packet_send(smb_krb5->packet, smb_krb5->request);
 			break;
 		case KRB5_KRBHST_HTTP:
-			talloc_free(smb_krb5);
+			talloc_free(tmp_ctx);
 			return EINVAL;
 		}
 		while ((NT_STATUS_IS_OK(smb_krb5->status)) && !smb_krb5->reply.length) {
 			if (tevent_loop_once(ev) != 0) {
-				talloc_free(smb_krb5);
+				talloc_free(tmp_ctx);
 				return EINVAL;
 			}
+
+			/* After each and every event loop, reset the
+			 * send_to_kdc pointers to what they were when
+			 * we entered this loop.  That way, if a
+			 * nested event has invalidated them, we put
+			 * it back before we return to the heimdal
+			 * code */
+			ret = krb5_set_send_to_kdc_func(context,
+							smb_krb5_send_and_recv_func,
+							data);
+			if (ret != 0) {
+				talloc_free(tmp_ctx);
+				return ret;
+			}
 		}
 		if (NT_STATUS_EQUAL(smb_krb5->status, NT_STATUS_IO_TIMEOUT)) {
 			talloc_free(smb_krb5);
@@ -341,13 +374,14 @@ krb5_error_code smb_krb5_send_and_recv_func(krb5_context context,
 
 		ret = krb5_data_copy(recv_buf, smb_krb5->reply.data, smb_krb5->reply.length);
 		if (ret) {
-			talloc_free(smb_krb5);
+			talloc_free(tmp_ctx);
 			return ret;
 		}
 		talloc_free(smb_krb5);
 
 		break;
 	}
+	talloc_free(tmp_ctx);
 	if (a) {
 		return 0;
 	}
@@ -415,7 +449,7 @@ smb_krb5_init_context_basic(TALLOC_CTX *tmp_ctx,
 krb5_error_code smb_krb5_init_context(void *parent_ctx,
 				      struct tevent_context *ev,
 				      struct loadparm_context *lp_ctx,
-				       struct smb_krb5_context **smb_krb5_context)
+				      struct smb_krb5_context **smb_krb5_context)
 {
 	krb5_error_code ret;
 	TALLOC_CTX *tmp_ctx;
@@ -423,7 +457,7 @@ krb5_error_code smb_krb5_init_context(void *parent_ctx,
 	initialize_krb5_error_table();
 
 	tmp_ctx = talloc_new(parent_ctx);
-	*smb_krb5_context = talloc(tmp_ctx, struct smb_krb5_context);
+	*smb_krb5_context = talloc_zero(tmp_ctx, struct smb_krb5_context);
 
 	if (!*smb_krb5_context || !tmp_ctx) {
 		talloc_free(tmp_ctx);
@@ -463,14 +497,14 @@ krb5_error_code smb_krb5_init_context(void *parent_ctx,
 	krb5_set_warn_dest((*smb_krb5_context)->krb5_context, (*smb_krb5_context)->logf);
 
 	/* Set use of our socket lib */
-	ret = krb5_set_send_to_kdc_func((*smb_krb5_context)->krb5_context,
-					smb_krb5_send_and_recv_func,
-					ev);
-	if (ret) {
-		DEBUG(1,("krb5_set_send_recv_func failed (%s)\n",
-			 smb_get_krb5_error_message((*smb_krb5_context)->krb5_context, ret, tmp_ctx)));
-		talloc_free(tmp_ctx);
-		return ret;
+	if (ev) {
+		struct tevent_context *previous_ev;
+		ret = smb_krb5_context_set_event_ctx(*smb_krb5_context,
+						     ev, &previous_ev);
+		if (ret) {
+			talloc_free(tmp_ctx);
+			return ret;
+		}
 	}
 
 	talloc_steal(parent_ctx, *smb_krb5_context);
@@ -484,3 +518,58 @@ krb5_error_code smb_krb5_init_context(void *parent_ctx,
 	return 0;
 }
 
+krb5_error_code smb_krb5_context_set_event_ctx(struct smb_krb5_context *smb_krb5_context,
+					       struct tevent_context *ev,
+					       struct tevent_context **previous_ev)
+{
+	int ret;
+	if (!ev) {
+		return EINVAL;
+	}
+
+	if (smb_krb5_context->current_ev) {
+		*previous_ev = smb_krb5_context->current_ev;
+	}
+
+	smb_krb5_context->current_ev = talloc_reference(smb_krb5_context, ev);
+	if (!smb_krb5_context->current_ev) {
+		return ENOMEM;
+	}
+
+	/* Set use of our socket lib */
+	ret = krb5_set_send_to_kdc_func(smb_krb5_context->krb5_context,
+					smb_krb5_send_and_recv_func,
+					ev);
+	if (ret) {
+		TALLOC_CTX *tmp_ctx = talloc_new(NULL);
+		DEBUG(1,("krb5_set_send_recv_func failed (%s)\n",
+			 smb_get_krb5_error_message(smb_krb5_context->krb5_context, ret, tmp_ctx)));
+		talloc_free(tmp_ctx);
+		talloc_unlink(smb_krb5_context, smb_krb5_context->current_ev);
+		smb_krb5_context->current_ev = NULL;
+		return ret;
+	}
+	return 0;
+}
+
+krb5_error_code smb_krb5_context_remove_event_ctx(struct smb_krb5_context *smb_krb5_context,
+						  struct tevent_context *previous_ev,
+						  struct tevent_context *ev)
+{
+	int ret;
+	talloc_unlink(smb_krb5_context, ev);
+	/* If there was a mismatch with things happening on a stack, then don't wipe things */
+	smb_krb5_context->current_ev = previous_ev;
+	/* Set use of our socket lib */
+	ret = krb5_set_send_to_kdc_func(smb_krb5_context->krb5_context,
+					smb_krb5_send_and_recv_func,
+					previous_ev);
+	if (ret) {
+		TALLOC_CTX *tmp_ctx = talloc_new(NULL);
+		DEBUG(1,("krb5_set_send_recv_func failed (%s)\n",
+			 smb_get_krb5_error_message(smb_krb5_context->krb5_context, ret, tmp_ctx)));
+		talloc_free(tmp_ctx);
+		return ret;
+	}
+	return 0;
+}
diff --git a/source4/auth/kerberos/krb5_init_context.h b/source4/auth/kerberos/krb5_init_context.h
index c55b2dc8bc..047772c8f7 100644
--- a/source4/auth/kerberos/krb5_init_context.h
+++ b/source4/auth/kerberos/krb5_init_context.h
@@ -20,6 +20,7 @@
 struct smb_krb5_context {
 	krb5_context krb5_context;
 	krb5_log_facility *logf;
+	struct tevent_context *current_ev;
 };
 	
 struct tevent_context;
diff --git a/source4/dsdb/samdb/samdb.c b/source4/dsdb/samdb/samdb.c
index 57de27a22e..d8c1728d3f 100644
--- a/source4/dsdb/samdb/samdb.c
+++ b/source4/dsdb/samdb/samdb.c
@@ -55,8 +55,7 @@ static int samdb_credentials_destructor(struct cli_credentials *creds)
   this returns a static set of system credentials. It is static so
   that we always get the same pointer in ldb_wrap_connect()
  */
-struct cli_credentials *samdb_credentials(struct tevent_context *event_ctx, 
-					  struct loadparm_context *lp_ctx)
+struct cli_credentials *samdb_credentials(struct loadparm_context *lp_ctx)
 {
 	static struct cli_credentials *static_credentials;
 	struct cli_credentials *cred;
@@ -77,7 +76,7 @@ struct cli_credentials *samdb_credentials(struct tevent_context *event_ctx,
 	 * anyway */
 	cli_credentials_set_kerberos_state(cred, CRED_DONT_USE_KERBEROS);
 
-	if (!NT_STATUS_IS_OK(cli_credentials_set_secrets(cred, event_ctx, lp_ctx, NULL, NULL,
+	if (!NT_STATUS_IS_OK(cli_credentials_set_secrets(cred, lp_ctx, NULL, NULL,
 							 SECRETS_LDAP_FILTER, &error_string))) {
 		DEBUG(5, ("(normal if no LDAP backend) %s", error_string));
 		/* Perfectly OK - if not against an LDAP backend */
@@ -106,7 +105,7 @@ struct ldb_context *samdb_connect(TALLOC_CTX *mem_ctx,
 	int ret;
 
 	url  = lpcfg_sam_url(lp_ctx);
-	credentials = samdb_credentials(ev_ctx, lp_ctx);
+	credentials = samdb_credentials(lp_ctx);
 
 	ldb = ldb_wrap_find(url, ev_ctx, lp_ctx, session_info, credentials, flags);
 	if (ldb != NULL)
diff --git a/source4/kdc/kpasswdd.c b/source4/kdc/kpasswdd.c
index 1ccae10eda..5254b62384 100644
--- a/source4/kdc/kpasswdd.c
+++ b/source4/kdc/kpasswdd.c
@@ -519,7 +519,7 @@ bool kpasswdd_process(struct kdc_server *kdc,
 	keytab_name = talloc_asprintf(server_credentials, "HDB:samba4&%p", kdc->base_ctx);
 
 	cli_credentials_set_username(server_credentials, "kadmin/changepw", CRED_SPECIFIED);
-	ret = cli_credentials_set_keytab_name(server_credentials, kdc->task->event_ctx, kdc->task->lp_ctx, keytab_name, CRED_SPECIFIED);
+	ret = cli_credentials_set_keytab_name(server_credentials, kdc->task->lp_ctx, keytab_name, CRED_SPECIFIED);
 	if (ret != 0) {
 		ret = kpasswdd_make_unauth_error_reply(kdc, mem_ctx,
 						       KRB5_KPASSWD_HARDERROR,
diff --git a/source4/smbd/service_named_pipe.c b/source4/smbd/service_named_pipe.c
index 84b490ac2d..7beab5676f 100644
--- a/source4/smbd/service_named_pipe.c
+++ b/source4/smbd/service_named_pipe.c
@@ -226,7 +226,6 @@ static void named_pipe_accept_done(struct tevent_req *subreq)
 		cli_credentials_set_anonymous(creds);
 
 		ret = cli_credentials_set_client_gss_creds(creds,
-							   conn->event.ctx,
 							   conn->lp_ctx,
 							   cred_handle,
 							   CRED_SPECIFIED,