winbind: Extend wbcAuthenticateUserEx to provide PAC

With this new interface, external applications that have authenticated
to an ADS can pass the PAC from the Kerberos ticket to
wbcAuthenticateUserEx. winbindd decodes and extracts the info3
information for the external application. If winbindd can verify the PAC
signature, the info3 from the PACis also added to the netsamlogon_cache.

The info3 data can be used by the external application to get the uid
and primary gid. The data in netsamlogon_cache allows to retrieve the
complete group list through the NSS function getgrouplist.

Signed-off-by: Andrew Bartlett <abartlet@samba.org>

3 files changed, 38 insertions, 21 deletions

diff --git a/nsswitch/libwbclient/wbc_pam.c b/nsswitch/libwbclient/wbc_pam.c
index f7fb9f23f6..f183cc61b1 100644
--- a/nsswitch/libwbclient/wbc_pam.c
+++ b/nsswitch/libwbclient/wbc_pam.c
@@ -364,7 +364,7 @@ wbcErr wbcAuthenticateUserEx(const struct wbcAuthUserParams *params,
 		BAIL_ON_WBC_ERROR(wbc_status);
 	}
 
-	if (!params->account_name) {
+	if (params->level != WBC_AUTH_USER_LEVEL_PAC && !params->account_name) {
 		wbc_status = WBC_ERR_INVALID_PARAM;
 		BAIL_ON_WBC_ERROR(wbc_status);
 	}
@@ -491,6 +491,20 @@ wbcErr wbcAuthenticateUserEx(const struct wbcAuthUserParams *params,
 			       request.data.auth_crap.nt_resp_len);
 		}
 		break;
+
+	case WBC_AUTH_USER_LEVEL_PAC:
+		cmd = WINBINDD_PAM_AUTH_CRAP;
+		request.flags = WBFLAG_PAM_AUTH_PAC | WBFLAG_PAM_INFO3_TEXT;
+		request.extra_data.data = malloc(params->password.pac.length);
+		if (request.extra_data.data == NULL) {
+			wbc_status = WBC_ERR_NO_MEMORY;
+			BAIL_ON_WBC_ERROR(wbc_status);
+		}
+		memcpy(request.extra_data.data, params->password.pac.data,
+		       params->password.pac.length);
+		request.extra_len = params->password.pac.length;
+		break;
+
 	default:
 		break;
 	}
diff --git a/nsswitch/libwbclient/wbclient.h b/nsswitch/libwbclient/wbclient.h
index cb70cbd513..473c9019d6 100644
--- a/nsswitch/libwbclient/wbclient.h
+++ b/nsswitch/libwbclient/wbclient.h
@@ -197,6 +197,25 @@ struct wbcDomainInfo {
 #define WBC_DOMINFO_TRUSTTYPE_EXTERNAL   0x00000003
 
 /**
+ * @brief Generic Blob
+ **/
+
+struct wbcBlob {
+	uint8_t *data;
+	size_t length;
+};
+
+/**
+ * @brief Named Blob
+ **/
+
+struct wbcNamedBlob {
+	const char *name;
+	uint32_t flags;
+	struct wbcBlob blob;
+};
+
+/**
  * @brief Auth User Parameters
  **/
 
@@ -212,7 +231,8 @@ struct wbcAuthUserParams {
 	enum wbcAuthUserLevel {
 		WBC_AUTH_USER_LEVEL_PLAIN = 1,
 		WBC_AUTH_USER_LEVEL_HASH = 2,
-		WBC_AUTH_USER_LEVEL_RESPONSE = 3
+		WBC_AUTH_USER_LEVEL_RESPONSE = 3,
+		WBC_AUTH_USER_LEVEL_PAC = 4
 	} level;
 	union {
 		const char *plaintext;
@@ -227,29 +247,11 @@ struct wbcAuthUserParams {
 			uint32_t lm_length;
 			uint8_t *lm_data;
 		} response;
+		struct wbcBlob pac;
 	} password;
 };
 
 /**
- * @brief Generic Blob
- **/
-
-struct wbcBlob {
-	uint8_t *data;
-	size_t length;
-};
-
-/**
- * @brief Named Blob
- **/
-
-struct wbcNamedBlob {
-	const char *name;
-	uint32_t flags;
-	struct wbcBlob blob;
-};
-
-/**
  * @brief Logon User Parameters
  **/
 
diff --git a/nsswitch/winbind_struct_protocol.h b/nsswitch/winbind_struct_protocol.h
index e5ed8e1b3a..c1704c8e0b 100644
--- a/nsswitch/winbind_struct_protocol.h
+++ b/nsswitch/winbind_struct_protocol.h
@@ -218,6 +218,7 @@ typedef struct winbindd_gr {
 #define WBFLAG_PAM_FALLBACK_AFTER_KRB5	0x00002000
 #define WBFLAG_PAM_CACHED_LOGIN		0x00004000
 #define WBFLAG_PAM_GET_PWD_POLICY	0x00008000
+#define WBFLAG_PAM_AUTH_PAC		0x00010000
 
 /* generic request flags */
 #define WBFLAG_QUERY_ONLY		0x00000020	/* not used */