Support for publishing TXT records via mDNS

- Update lwIP+Raspberry Pi implementation to use lwIP API correctly
- Add translations
This commit is contained in:
Daniel James 2023-07-30 19:39:34 -07:00
parent 5f95232495
commit f9d3ec5027
No known key found for this signature in database
7 changed files with 92 additions and 8 deletions

View File

@ -1018,6 +1018,15 @@ msgstr ""
msgid "Failed to acquire mutex, err 0x%04x"
msgstr ""
#: ports/raspberrypi/common-hal/mdns/Server.c
msgid "Failed to add service TXT record"
msgstr ""
#: shared-bindings/mdns/Server.c
msgid ""
"Failed to add service TXT record; non-string or bytes found in txt_records"
msgstr ""
#: shared-module/rgbmatrix/RGBMatrix.c
msgid "Failed to allocate %q buffer"
msgstr ""

View File

@ -208,10 +208,25 @@ mp_obj_t common_hal_mdns_server_find(mdns_server_obj_t *self, const char *servic
return MP_OBJ_FROM_PTR(tuple);
}
void common_hal_mdns_server_advertise_service(mdns_server_obj_t *self, const char *service_type, const char *protocol, mp_int_t port) {
void common_hal_mdns_server_advertise_service(mdns_server_obj_t *self, const char *service_type, const char *protocol, mp_int_t port, const char *txt_records[], size_t num_txt_records) {
if (mdns_service_exists(service_type, protocol, NULL)) {
mdns_service_port_set(service_type, protocol, port);
} else {
// TODO: Add support for TXT record
/* NOTE: The `mdns_txt_item_t *txt` argument of mdns_service_add uses a struct
* that splits out the TXT record into keys and values, though it seems little
* is done with those fields aside from concatenating them with an optional
* equals sign and calculating the total length of the concatenated string.
*
* There should be little issue with the underlying implementation to populate
* the mdns_txt_item_t struct with only a key containing exactly the desired TXT
* record. As long as the underlying implementation calculates the length of the
* key + NULL value correctly, it should work.
*
* Ref: RFC 6763, section 6.1:
* > The format of each constituent string within the DNS TXT record is a single
* > length byte, followed by 0-255 bytes of text data.
*/
mdns_service_add(NULL, service_type, protocol, port, NULL, 0);
}
}

View File

@ -30,6 +30,7 @@
#include "py/runtime.h"
#include "shared/runtime/interrupt_char.h"
#include "shared-bindings/mdns/RemoteService.h"
#include "shared-bindings/mdns/Server.h"
#include "shared-bindings/wifi/__init__.h"
#include "supervisor/shared/tick.h"
@ -295,7 +296,27 @@ mp_obj_t common_hal_mdns_server_find(mdns_server_obj_t *self, const char *servic
return MP_OBJ_FROM_PTR(tuple);
}
void common_hal_mdns_server_advertise_service(mdns_server_obj_t *self, const char *service_type, const char *protocol, mp_int_t port) {
STATIC void srv_txt_cb(struct mdns_service *service, void *ptr) {
mdns_server_obj_t *self = ptr;
err_t res;
for (size_t i = 0; i < self->num_txt_records; i++) {
res = mdns_resp_add_service_txtitem(service, self->txt_records[i], strlen(self->txt_records[i]));
if (res != ERR_OK) {
mp_raise_RuntimeError(translate("Failed to add service TXT record"));
return;
}
}
}
STATIC void assign_txt_records(mdns_server_obj_t *self, const char *txt_records[], size_t num_txt_records) {
size_t allowed_num_txt_records = MDNS_MAX_TXT_RECORDS < num_txt_records ? MDNS_MAX_TXT_RECORDS : num_txt_records;
self->num_txt_records = allowed_num_txt_records;
for (size_t i = 0; i < allowed_num_txt_records; i++) {
self->txt_records[i] = txt_records[i];
}
}
void common_hal_mdns_server_advertise_service(mdns_server_obj_t *self, const char *service_type, const char *protocol, mp_int_t port, const char *txt_records[], size_t num_txt_records) {
enum mdns_sd_proto proto = DNSSD_PROTO_UDP;
if (strcmp(protocol, "_tcp") == 0) {
proto = DNSSD_PROTO_TCP;
@ -313,7 +334,9 @@ void common_hal_mdns_server_advertise_service(mdns_server_obj_t *self, const cha
if (existing_slot < MDNS_MAX_SERVICES) {
mdns_resp_del_service(NETIF_STA, existing_slot);
}
int8_t slot = mdns_resp_add_service(NETIF_STA, self->instance_name, service_type, proto, port, NULL, NULL);
assign_txt_records(self, txt_records, num_txt_records);
int8_t slot = mdns_resp_add_service(NETIF_STA, self->instance_name, service_type, proto, port, srv_txt_cb, self);
if (slot < 0) {
mp_raise_RuntimeError(MP_ERROR_TEXT("Out of MDNS service slots"));
return;

View File

@ -30,12 +30,16 @@
#include "lwip/apps/mdns_opts.h"
#define MDNS_MAX_TXT_RECORDS 32
typedef struct {
mp_obj_base_t base;
const char *hostname;
const char *instance_name;
char default_hostname[sizeof("cpy-XXXXXX")];
const char *service_type[MDNS_MAX_SERVICES];
size_t num_txt_records;
const char *txt_records[MDNS_MAX_TXT_RECORDS];
// Track if this object owns access to the underlying MDNS service.
bool inited;
} mdns_server_obj_t;

View File

@ -27,7 +27,9 @@
#include <string.h>
#include "py/obj.h"
#include "py/objproperty.h"
#include "py/objstr.h"
#include "py/runtime.h"
#include "shared-bindings/mdns/__init__.h"
#include "shared-bindings/mdns/Server.h"
@ -173,20 +175,26 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mdns_server_find_obj, 1, _mdns_server_find);
//|
//| If web workflow is active, the port it uses can't also be used to advertise a service.
//|
//| **Limitations**: Publishing up to 32 TXT records is only supported on the RP2040 Pico W board at
//| this time.
//|
//| :param str service_type: The service type such as "_http"
//| :param str protocol: The service protocol such as "_tcp"
//| :param int port: The port used by the service"""
//| :param int port: The port used by the service
//| :param Sequence[str] txt_records: An optional sequence of strings to serve as TXT records along with the service
//| """
//| ...
//|
STATIC mp_obj_t mdns_server_advertise_service(mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
mdns_server_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
check_for_deinit(self);
enum { ARG_service_type, ARG_protocol, ARG_port };
enum { ARG_service_type, ARG_protocol, ARG_port, ARG_txt_records };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_service_type, MP_ARG_KW_ONLY | MP_ARG_REQUIRED | MP_ARG_OBJ },
{ MP_QSTR_protocol, MP_ARG_KW_ONLY | MP_ARG_REQUIRED | MP_ARG_OBJ },
{ MP_QSTR_port, MP_ARG_KW_ONLY | MP_ARG_REQUIRED | MP_ARG_INT },
{ MP_QSTR_txt_records, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
};
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
@ -195,7 +203,21 @@ STATIC mp_obj_t mdns_server_advertise_service(mp_uint_t n_args, const mp_obj_t *
const char *service_type = mp_obj_str_get_str(args[ARG_service_type].u_obj);
const char *protocol = mp_obj_str_get_str(args[ARG_protocol].u_obj);
common_hal_mdns_server_advertise_service(self, service_type, protocol, args[ARG_port].u_int);
const mp_obj_t txt_records = args[ARG_txt_records].u_obj;
const size_t num_txt_records = txt_records == mp_const_none
? 0
: (size_t)MP_OBJ_SMALL_INT_VALUE(mp_obj_len(txt_records));
const char *txt_records_array[num_txt_records];
for (size_t i = 0; i < num_txt_records; i++) {
mp_obj_t txt_record = mp_obj_subscr(txt_records, MP_OBJ_NEW_SMALL_INT(i), MP_OBJ_SENTINEL);
if (!mp_obj_is_str_or_bytes(txt_record)) {
mp_raise_ValueError(translate("Failed to add service TXT record; non-string or bytes found in txt_records"));
}
txt_records_array[i] = mp_obj_str_get_str(txt_record);
}
common_hal_mdns_server_advertise_service(self, service_type, protocol, args[ARG_port].u_int, txt_records_array, num_txt_records);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mdns_server_advertise_service_obj, 1, mdns_server_advertise_service);

View File

@ -42,7 +42,18 @@ void common_hal_mdns_server_set_hostname(mdns_server_obj_t *self, const char *ho
const char *common_hal_mdns_server_get_instance_name(mdns_server_obj_t *self);
void common_hal_mdns_server_set_instance_name(mdns_server_obj_t *self, const char *instance_name);
mp_obj_t common_hal_mdns_server_find(mdns_server_obj_t *self, const char *service_type, const char *protocol, mp_float_t timeout);
void common_hal_mdns_server_advertise_service(mdns_server_obj_t *self, const char *service_type, const char *protocol, mp_int_t port);
/**
* @brief Advertises service
*
* @param self
* @param service_type A string indicating the DNS-SD type of service being advertised (e.g., _http)
* @param protocol A string indicating the DNS-SD protocol of the service (e.g., _tcp or _udp)
* @param port The TCP or UDP port number of the service
* @param txt_records An array of strings representing TXT records to publish along with the service
* @param num_txt_records Number of records expected in txt_records
*/
void common_hal_mdns_server_advertise_service(mdns_server_obj_t *self, const char *service_type, const char *protocol, mp_int_t port, const char *txt_records[], size_t num_txt_records);
// For internal use.
void mdns_server_construct(mdns_server_obj_t *self, bool workflow);

View File

@ -355,7 +355,7 @@ bool supervisor_start_web_workflow(bool reload) {
}
}
if (!common_hal_mdns_server_deinited(&mdns)) {
common_hal_mdns_server_advertise_service(&mdns, "_circuitpython", "_tcp", web_api_port);
common_hal_mdns_server_advertise_service(&mdns, "_circuitpython", "_tcp", web_api_port, NULL, 0);
}
#endif