/* common routines for audit logging Copyright (C) Andrew Bartlett 2018 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 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, see . */ /* * Error handling: * */ #include "includes.h" #include "librpc/ndr/libndr.h" #include "lib/tsocket/tsocket.h" #include "libcli/security/dom_sid.h" #include "lib/messaging/messaging.h" #include "auth/common_auth.h" #include "audit_logging.h" /* * @brief Get a human readable timestamp. * * Returns the current time formatted as * "Tue, 14 Mar 2017 08:38:42.209028 NZDT" * * The returned string is allocated by talloc in the supplied context. * It is the callers responsibility to free it. * * @param mem_ctx talloc memory context that owns the returned string. * * @return a human readable time stamp, or NULL in the event of an error. * */ char* audit_get_timestamp(TALLOC_CTX *frame) { char buffer[40]; /* formatted time less usec and timezone */ char tz[10]; /* formatted time zone */ struct tm* tm_info; /* current local time */ struct timeval tv; /* current system time */ int ret; /* response code */ char * ts; /* formatted time stamp */ ret = gettimeofday(&tv, NULL); if (ret != 0) { DBG_ERR("Unable to get time of day: (%d) %s\n", errno, strerror(errno)); return NULL; } tm_info = localtime(&tv.tv_sec); if (tm_info == NULL) { DBG_ERR("Unable to determine local time\n"); return NULL; } strftime(buffer, sizeof(buffer)-1, "%a, %d %b %Y %H:%M:%S", tm_info); strftime(tz, sizeof(tz)-1, "%Z", tm_info); ts = talloc_asprintf(frame, "%s.%06ld %s", buffer, tv.tv_usec, tz); if (ts == NULL) { DBG_ERR("Out of memory formatting time stamp\n"); } return ts; } /* * @brief write an audit message to the audit logs. * * Write a human readable text audit message to the samba logs. * * @param prefix Text to be printed at the start of the log line * @param message The content of the log line. * @param debub_class The debug class to log the message with. * @param debug_level The debug level to log the message with. */ void audit_log_human_text(const char* prefix, const char* message, int debug_class, int debug_level) { DEBUGC(debug_class, debug_level, ("%s %s\n", prefix, message)); } #ifdef HAVE_JANSSON /* * Constant for empty json object initialisation */ const struct json_object json_empty_object = {.valid = false, .root = NULL}; /* * @brief write a json object to the samba audit logs. * * Write the json object to the audit logs as a formatted string * * @param message The content of the log line. * @param debub_class The debug class to log the message with. * @param debug_level The debug level to log the message with. */ void audit_log_json(struct json_object* message, int debug_class, int debug_level) { TALLOC_CTX *frame = NULL; char *s = NULL; if (json_is_invalid(message)) { DBG_ERR("Invalid JSON object, unable to log\n"); return; } frame = talloc_stackframe(); s = json_to_string(frame, message); if (s == NULL) { DBG_ERR("json_to_string returned NULL, " "JSON audit message could not written\n"); TALLOC_FREE(frame); return; } /* * This is very strange, but we call this routine to get a log * output without the header. JSON logs all have timestamps * so this only makes parsing harder. * * We push out the raw JSON blob without a prefix, consumers * can find such lines by the leading { */ DEBUGADDC(debug_class, debug_level, ("%s\n", s)); TALLOC_FREE(frame); } /* * @brief get a connection to the messaging event server. * * Get a connection to the messaging event server registered by server_name. * * @param msg_ctx a valid imessaging_context. * @param server_name name of messaging event server to connect to. * @param server_id The event server details to populate * * @return NTSTATUS */ static NTSTATUS get_event_server( struct imessaging_context *msg_ctx, const char *server_name, struct server_id *event_server) { NTSTATUS status; TALLOC_CTX *frame = talloc_stackframe(); unsigned num_servers, i; struct server_id *servers; status = irpc_servers_byname( msg_ctx, frame, server_name, &num_servers, &servers); if (!NT_STATUS_IS_OK(status)) { DBG_DEBUG("Failed to find the target '%s' on the message bus " "to send JSON audit events to: %s\n", server_name, nt_errstr(status)); TALLOC_FREE(frame); return status; } /* * Select the first server that is listening, because we get * connection refused as NT_STATUS_OBJECT_NAME_NOT_FOUND * without waiting */ for (i = 0; i < num_servers; i++) { status = imessaging_send( msg_ctx, servers[i], MSG_PING, &data_blob_null); if (NT_STATUS_IS_OK(status)) { *event_server = servers[i]; TALLOC_FREE(frame); return NT_STATUS_OK; } } DBG_NOTICE( "Failed to find '%s' registered on the message bus to " "send JSON audit events to: %s\n", server_name, nt_errstr(status)); TALLOC_FREE(frame); return NT_STATUS_OBJECT_NAME_NOT_FOUND; } /* * @brief send an audit message to a messaging event server. * * Send the message to a registered and listening event server. * Note: Any errors are logged, and the message is not sent. This is to ensure * that a poorly behaved event server does not impact Samba. * * As it is possible to lose messages, especially during server * shut down, currently this function is primarily intended for use * in integration tests. * * @param msg_ctx an imessaging_context, can be NULL in which case no message * will be sent. * @param server_name the naname of the event server to send the message to. * @param messag_type A message type defined in librpc/idl/messaging.idl * @param message The message to send. * */ void audit_message_send( struct imessaging_context *msg_ctx, const char *server_name, uint32_t message_type, struct json_object *message) { struct server_id event_server = { .pid = 0, }; NTSTATUS status; const char *message_string = NULL; DATA_BLOB message_blob = data_blob_null; TALLOC_CTX *ctx = NULL; if (json_is_invalid(message)) { DBG_ERR("Invalid JSON object, unable to send\n"); return; } if (msg_ctx == NULL) { DBG_DEBUG("No messaging context\n"); return; } ctx = talloc_new(NULL); if (ctx == NULL) { DBG_ERR("Out of memory creating temporary context\n"); return; } /* Need to refetch the address each time as the destination server may * have disconnected and reconnected in the interim, in which case * messages may get lost */ status = get_event_server(msg_ctx, server_name, &event_server); if (!NT_STATUS_IS_OK(status)) { TALLOC_FREE(ctx); return; } message_string = json_to_string(ctx, message); message_blob = data_blob_string_const(message_string); status = imessaging_send( msg_ctx, event_server, message_type, &message_blob); /* * If the server crashed, try to find it again */ if (NT_STATUS_EQUAL(status, NT_STATUS_OBJECT_NAME_NOT_FOUND)) { status = get_event_server(msg_ctx, server_name, &event_server); if (!NT_STATUS_IS_OK(status)) { TALLOC_FREE(ctx); return; } imessaging_send( msg_ctx, event_server, message_type, &message_blob); } TALLOC_FREE(ctx); } /* * @brief Create a new struct json_object, wrapping a JSON Object. * * Create a new json object, the json_object wraps the underlying json * implementations JSON Object representation. * * Free with a call to json_free_object, note that the jansson inplementation * allocates memory with malloc and not talloc. * * @return a struct json_object, valid will be set to false if the object * could not be created. * */ struct json_object json_new_object(void) { struct json_object object = json_empty_object; object.root = json_object(); if (object.root == NULL) { object.valid = false; DBG_ERR("Unable to create JSON object\n"); return object; } object.valid = true; return object; } /* * @brief Create a new struct json_object wrapping a JSON Array. * * Create a new json object, the json_object wraps the underlying json * implementations JSON Array representation. * * Free with a call to json_free_object, note that the jansson inplementation * allocates memory with malloc and not talloc. * * @return a struct json_object, error will be set to true if the array * could not be created. * */ struct json_object json_new_array(void) { struct json_object array = json_empty_object; array.root = json_array(); if (array.root == NULL) { array.valid = false; DBG_ERR("Unable to create JSON array\n"); return array; } array.valid = true; return array; } /* * @brief free and invalidate a previously created JSON object. * * Release any resources owned by a json_object, and then mark the structure * as invalid. It is safe to call this multiple times on an object. * */ void json_free(struct json_object *object) { if (object->root != NULL) { json_decref(object->root); } object->root = NULL; object->valid = false; } /* * @brief is the current JSON object invalid? * * Check the state of the object to determine if it is invalid. * * @return is the object valid? * */ bool json_is_invalid(const struct json_object *object) { return !object->valid; } /* * @brief Add an integer value to a JSON object. * * Add an integer value named 'name' to the json object. * * @param object the JSON object to be updated. * @param name the name of the value. * @param value the value. * * @return 0 the operation was successful * -1 the operation failed * */ int json_add_int(struct json_object *object, const char *name, const int value) { int ret = 0; json_t *integer = NULL; if (json_is_invalid(object)) { DBG_ERR("Unable to add int [%s] value [%d], " "target object is invalid\n", name, value); return JSON_ERROR; } integer = json_integer(value); if (integer == NULL) { DBG_ERR("Unable to create integer value [%s] value [%d]\n", name, value); return JSON_ERROR; } ret = json_object_set_new(object->root, name, integer); if (ret != 0) { json_decref(integer); DBG_ERR("Unable to add int [%s] value [%d]\n", name, value); } return ret; } /* * @brief Add a boolean value to a JSON object. * * Add a boolean value named 'name' to the json object. * * @param object the JSON object to be updated. * @param name the name. * @param value the value. * * @return 0 the operation was successful * -1 the operation failed * */ int json_add_bool(struct json_object *object, const char *name, const bool value) { int ret = 0; if (json_is_invalid(object)) { DBG_ERR("Unable to add boolean [%s] value [%d], " "target object is invalid\n", name, value); return JSON_ERROR; } ret = json_object_set_new(object->root, name, json_boolean(value)); if (ret != 0) { DBG_ERR("Unable to add boolean [%s] value [%d]\n", name, value); } return ret; } /* * @brief Add a string value to a JSON object. * * Add a string value named 'name' to the json object. * * @param object the JSON object to be updated. * @param name the name. * @param value the value. * * @return 0 the operation was successful * -1 the operation failed * */ int json_add_string(struct json_object *object, const char *name, const char *value) { int ret = 0; if (json_is_invalid(object)) { DBG_ERR("Unable to add string [%s], target object is invalid\n", name); return JSON_ERROR; } if (value) { json_t *string = json_string(value); if (string == NULL) { DBG_ERR("Unable to add string [%s], " "could not create string object\n", name); return JSON_ERROR; } ret = json_object_set_new(object->root, name, string); if (ret != 0) { json_decref(string); DBG_ERR("Unable to add string [%s]\n", name); return ret; } } else { ret = json_object_set_new(object->root, name, json_null()); if (ret != 0) { DBG_ERR("Unable to add null string [%s]\n", name); return ret; } } return ret; } /* * @brief Assert that the current JSON object is an array. * * Check that the current object is a JSON array, and if not * invalidate the object. We also log an error message as this indicates * bug in the calling code. * * @param object the JSON object to be validated. */ void json_assert_is_array(struct json_object *array) { if (json_is_invalid(array)) { return; } if (json_is_array(array->root) == false) { DBG_ERR("JSON object is not an array\n"); array->valid = false; return; } } /* * @brief Add a JSON object to a JSON object. * * Add a JSON object named 'name' to the json object. * * @param object the JSON object to be updated. * @param name the name. * @param value the value. * * @return 0 the operation was successful * -1 the operation failed * */ int json_add_object(struct json_object *object, const char *name, struct json_object *value) { int ret = 0; json_t *jv = NULL; if (value != NULL && json_is_invalid(value)) { DBG_ERR("Invalid JSON object [%s] supplied\n", name); return JSON_ERROR; } if (json_is_invalid(object)) { DBG_ERR("Unable to add object [%s], target object is invalid\n", name); return JSON_ERROR; } jv = value == NULL ? json_null() : value->root; if (json_is_array(object->root)) { ret = json_array_append_new(object->root, jv); } else if (json_is_object(object->root)) { ret = json_object_set_new(object->root, name, jv); } else { DBG_ERR("Invalid JSON object type\n"); ret = JSON_ERROR; } if (ret != 0) { DBG_ERR("Unable to add object [%s]\n", name); } return ret; } /* * @brief Add a string to a JSON object, truncating if necessary. * * * Add a string value named 'name' to the json object, the string will be * truncated if it is more than len characters long. If len is 0 the value * is encoded as a JSON null. * * * @param object the JSON object to be updated. * @param name the name. * @param value the value. * @param len the maximum number of characters to be copied. * * @return 0 the operation was successful * -1 the operation failed * */ int json_add_stringn(struct json_object *object, const char *name, const char *value, const size_t len) { int ret = 0; if (json_is_invalid(object)) { DBG_ERR("Unable to add string [%s], target object is invalid\n", name); return JSON_ERROR; } if (value != NULL && len > 0) { json_t *string = NULL; char buffer[len+1]; strncpy(buffer, value, len); buffer[len] = '\0'; string = json_string(buffer); if (string == NULL) { DBG_ERR("Unable to add string [%s], " "could not create string object\n", name); return JSON_ERROR; } ret = json_object_set_new(object->root, name, string); if (ret != 0) { json_decref(string); DBG_ERR("Unable to add string [%s]\n", name); return ret; } } else { ret = json_object_set_new(object->root, name, json_null()); if (ret != 0) { DBG_ERR("Unable to add null string [%s]\n", name); return ret; } } return ret; } /* * @brief Add a version object to a JSON object * * Add a version object to the JSON object * "version":{"major":1, "minor":0} * * The version tag is intended to aid the processing of the JSON messages * The major version number should change when an attribute is: * - renamed * - removed * - its meaning changes * - its contents change format * The minor version should change whenever a new attribute is added and for * minor bug fixes to an attributes content. * * * @param object the JSON object to be updated. * @param major the major version number * @param minor the minor version number * * @return 0 the operation was successful * -1 the operation failed */ int json_add_version(struct json_object *object, int major, int minor) { int ret = 0; struct json_object version; if (json_is_invalid(object)) { DBG_ERR("Unable to add version, target object is invalid\n"); return JSON_ERROR; } version = json_new_object(); if (json_is_invalid(&version)) { DBG_ERR("Unable to add version, failed to create object\n"); return JSON_ERROR; } ret = json_add_int(&version, "major", major); if (ret != 0) { json_free(&version); return ret; } ret = json_add_int(&version, "minor", minor); if (ret != 0) { json_free(&version); return ret; } ret = json_add_object(object, "version", &version); if (ret != 0) { json_free(&version); return ret; } return ret; } /* * @brief add an ISO 8601 timestamp to the object. * * Add the current date and time as a timestamp in ISO 8601 format * to a JSON object * * "timestamp":"2017-03-06T17:18:04.455081+1300" * * * @param object the JSON object to be updated. * * @return 0 the operation was successful * -1 the operation failed */ int json_add_timestamp(struct json_object *object) { char buffer[40]; /* formatted time less usec and timezone */ char timestamp[65]; /* the formatted ISO 8601 time stamp */ char tz[10]; /* formatted time zone */ struct tm* tm_info; /* current local time */ struct timeval tv; /* current system time */ int r; /* response code from gettimeofday */ int ret; /* return code from json operations */ if (json_is_invalid(object)) { DBG_ERR("Unable to add time stamp, target object is invalid\n"); return JSON_ERROR; } r = gettimeofday(&tv, NULL); if (r) { DBG_ERR("Unable to get time of day: (%d) %s\n", errno, strerror(errno)); return JSON_ERROR; } tm_info = localtime(&tv.tv_sec); if (tm_info == NULL) { DBG_ERR("Unable to determine local time\n"); return JSON_ERROR; } strftime(buffer, sizeof(buffer)-1, "%Y-%m-%dT%T", tm_info); strftime(tz, sizeof(tz)-1, "%z", tm_info); snprintf( timestamp, sizeof(timestamp), "%s.%06ld%s", buffer, tv.tv_usec, tz); ret = json_add_string(object, "timestamp", timestamp); if (ret != 0) { DBG_ERR("Unable to add time stamp to JSON object\n"); } return ret; } /* *@brief Add a tsocket_address to a JSON object * * Add the string representation of a Samba tsocket_address to the object. * * "localAddress":"ipv6::::0" * * * @param object the JSON object to be updated. * @param name the name. * @param address the tsocket_address. * * @return 0 the operation was successful * -1 the operation failed * */ int json_add_address(struct json_object *object, const char *name, const struct tsocket_address *address) { int ret = 0; if (json_is_invalid(object)) { DBG_ERR("Unable to add address [%s], " "target object is invalid\n", name); return JSON_ERROR; } if (address == NULL) { ret = json_object_set_new(object->root, name, json_null()); if (ret != 0) { DBG_ERR("Unable to add null address [%s]\n", name); return JSON_ERROR; } } else { TALLOC_CTX *ctx = talloc_new(NULL); char *s = NULL; if (ctx == NULL) { DBG_ERR("Out of memory adding address [%s]\n", name); return JSON_ERROR; } s = tsocket_address_string(address, ctx); if (s == NULL) { DBG_ERR("Out of memory adding address [%s]\n", name); TALLOC_FREE(ctx); return JSON_ERROR; } ret = json_add_string(object, name, s); if (ret != 0) { DBG_ERR( "Unable to add address [%s] value [%s]\n", name, s); TALLOC_FREE(ctx); return JSON_ERROR; } TALLOC_FREE(ctx); } return ret; } /* * @brief Add a formatted string representation of a sid to a json object. * * Add the string representation of a Samba sid to the object. * * "sid":"S-1-5-18" * * * @param object the JSON object to be updated. * @param name the name. * @param sid the sid * * @return 0 the operation was successful * -1 the operation failed * */ int json_add_sid(struct json_object *object, const char *name, const struct dom_sid *sid) { int ret = 0; if (json_is_invalid(object)) { DBG_ERR("Unable to add SID [%s], " "target object is invalid\n", name); return JSON_ERROR; } if (sid == NULL) { ret = json_object_set_new(object->root, name, json_null()); if (ret != 0) { DBG_ERR("Unable to add null SID [%s]\n", name); return ret; } } else { struct dom_sid_buf sid_buf; ret = json_add_string( object, name, dom_sid_str_buf(sid, &sid_buf)); if (ret != 0) { DBG_ERR("Unable to add SID [%s] value [%s]\n", name, sid_buf.buf); return ret; } } return ret; } /* * @brief Add a formatted string representation of a guid to a json object. * * Add the string representation of a Samba GUID to the object. * * "guid":"1fb9f2ee-2a4d-4bf8-af8b-cb9d4529a9ab" * * * @param object the JSON object to be updated. * @param name the name. * @param guid the guid. * * @return 0 the operation was successful * -1 the operation failed * * */ int json_add_guid(struct json_object *object, const char *name, const struct GUID *guid) { int ret = 0; if (json_is_invalid(object)) { DBG_ERR("Unable to add GUID [%s], " "target object is invalid\n", name); return JSON_ERROR; } if (guid == NULL) { ret = json_object_set_new(object->root, name, json_null()); if (ret != 0) { DBG_ERR("Unable to add null GUID [%s]\n", name); return ret; } } else { char *guid_str; struct GUID_txt_buf guid_buff; guid_str = GUID_buf_string(guid, &guid_buff); ret = json_add_string(object, name, guid_str); if (ret != 0) { DBG_ERR("Unable to guid GUID [%s] value [%s]\n", name, guid_str); return ret; } } return ret; } /* * @brief Convert a JSON object into a string * * Convert the jsom object into a string suitable for printing on a log line, * i.e. with no embedded line breaks. * * If the object is invalid it logs an error and returns NULL. * * @param mem_ctx the talloc memory context owning the returned string * @param object the json object. * * @return A string representation of the object or NULL if the object * is invalid. */ char *json_to_string(TALLOC_CTX *mem_ctx, const struct json_object *object) { char *json = NULL; char *json_string = NULL; if (json_is_invalid(object)) { DBG_ERR("Invalid JSON object, unable to convert to string\n"); return NULL; } if (object->root == NULL) { return NULL; } /* * json_dumps uses malloc, so need to call free(json) to release * the memory */ json = json_dumps(object->root, 0); if (json == NULL) { DBG_ERR("Unable to convert JSON object to string\n"); return NULL; } json_string = talloc_strdup(mem_ctx, json); if (json_string == NULL) { free(json); DBG_ERR("Unable to copy JSON object string to talloc string\n"); return NULL; } free(json); return json_string; } /* * @brief get a json array named "name" from the json object. * * Get the array attribute named name, creating it if it does not exist. * * @param object the json object. * @param name the name of the array attribute * * @return The array object, will be created if it did not exist. */ struct json_object json_get_array(struct json_object *object, const char *name) { struct json_object array = json_empty_object; json_t *a = NULL; int ret = 0; if (json_is_invalid(object)) { DBG_ERR("Invalid JSON object, unable to get array [%s]\n", name); json_free(&array); return array; } array = json_new_array(); if (json_is_invalid(&array)) { DBG_ERR("Unable to create new array for [%s]\n", name); return array; } a = json_object_get(object->root, name); if (a == NULL) { return array; } ret = json_array_extend(array.root, a); if (ret != 0) { DBG_ERR("Unable to get array [%s]\n", name); json_free(&array); return array; } return array; } /* * @brief get a json object named "name" from the json object. * * Get the object attribute named name, creating it if it does not exist. * * @param object the json object. * @param name the name of the object attribute * * @return The object, will be created if it did not exist. */ struct json_object json_get_object(struct json_object *object, const char *name) { struct json_object o = json_new_object(); json_t *v = NULL; int ret = 0; if (json_is_invalid(object)) { DBG_ERR("Invalid JSON object, unable to get object [%s]\n", name); json_free(&o); return o; } v = json_object_get(object->root, name); if (v == NULL) { return o; } ret = json_object_update(o.root, v); if (ret != 0) { DBG_ERR("Unable to get object [%s]\n", name); json_free(&o); return o; } return o; } #endif