extmod/network_ppp_lwip.c - lite/micropython - Linaro Git Browser

 /*
  * This file is part of the MicroPython project, http://micropython.org/
  *
  * The MIT License (MIT)
  *
  * Copyright (c) 2024 Damien P. George
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */

 // This file is intended to closely match ports/esp32/network_ppp.c. Changes can
 // and should probably be applied to both files. Compare them directly by using:
 // git diff --no-index extmod/network_ppp_lwip.c ports/esp32/network_ppp.c

 #include "py/runtime.h"
 #include "py/mphal.h"
 #include "py/stream.h"
 #include "extmod/modnetwork.h"

 #if MICROPY_PY_NETWORK_PPP_LWIP

 #include "lwip/dns.h"
 #include "netif/ppp/ppp.h"
 #include "netif/ppp/pppapi.h"
 #include "netif/ppp/pppos.h"

 // Enable this to see the serial data going between the PPP layer.
 #define PPP_TRACE_IN_OUT (0)

 typedef enum {
     STATE_INACTIVE,
     STATE_ACTIVE,
     STATE_ERROR,
     STATE_CONNECTING,
     STATE_CONNECTED,
 } network_ppp_state_t;

 typedef struct _network_ppp_obj_t {
     mp_obj_base_t base;
     network_ppp_state_t state;
     int error_code;
     mp_obj_t stream;
     ppp_pcb *pcb;
     struct netif netif;
 } network_ppp_obj_t;

 const mp_obj_type_t mp_network_ppp_lwip_type;

 static mp_obj_t network_ppp___del__(mp_obj_t self_in);

 static void network_ppp_stream_uart_irq_disable(network_ppp_obj_t *self) {
     if (self->stream == mp_const_none) {
         return;
     }

     // Disable UART IRQ.
     mp_obj_t dest[3];
     mp_load_method(self->stream, MP_QSTR_irq, dest);
     dest[2] = mp_const_none;
     mp_call_method_n_kw(1, 0, dest);
 }

 static void network_ppp_status_cb(ppp_pcb *pcb, int err_code, void *ctx) {
     network_ppp_obj_t *self = ctx;
     switch (err_code) {
         case PPPERR_NONE:
             self->state = STATE_CONNECTED;
             break;
         case PPPERR_USER:
             if (self->state >= STATE_ERROR) {
                 // Indicate that we are no longer connected and thus
                 // only need to free the PPP PCB, not close it.
                 self->state = STATE_ACTIVE;
             }
             // Clean up the PPP PCB.
             network_ppp___del__(MP_OBJ_FROM_PTR(self));
             break;
         default:
             self->state = STATE_ERROR;
             self->error_code = err_code;
             break;
     }
 }

 static mp_obj_t network_ppp_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
     mp_arg_check_num(n_args, n_kw, 1, 1, false);

     mp_obj_t stream = all_args[0];

     if (stream != mp_const_none) {
         mp_get_stream_raise(stream, MP_STREAM_OP_READ | MP_STREAM_OP_WRITE);
     }

     network_ppp_obj_t *self = mp_obj_malloc_with_finaliser(network_ppp_obj_t, type);
     self->state = STATE_INACTIVE;
     self->stream = stream;
     self->pcb = NULL;

     return MP_OBJ_FROM_PTR(self);
 }

 static mp_obj_t network_ppp___del__(mp_obj_t self_in) {
     network_ppp_obj_t *self = MP_OBJ_TO_PTR(self_in);
     if (self->state >= STATE_ACTIVE) {
         if (self->state >= STATE_ERROR) {
             // Still connected over the stream.
             // Force the connection to close, with nocarrier=1.
             self->state = STATE_INACTIVE;
             ppp_close(self->pcb, 1);
         }
         network_ppp_stream_uart_irq_disable(self);
         // Free PPP PCB and reset state.
         self->state = STATE_INACTIVE;
         ppp_free(self->pcb);
         self->pcb = NULL;
     }
     return mp_const_none;
 }
 static MP_DEFINE_CONST_FUN_OBJ_1(network_ppp___del___obj, network_ppp___del__);

 static mp_obj_t network_ppp_poll(size_t n_args, const mp_obj_t *args) {
     network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);

     if (self->state <= STATE_ERROR) {
         return MP_OBJ_NEW_SMALL_INT(-MP_EPERM);
     }

     mp_int_t total_len = 0;
     mp_obj_t stream = self->stream;
     while (stream != mp_const_none) {
         uint8_t buf[256];
         int err;
         mp_uint_t len = mp_stream_rw(stream, buf, sizeof(buf), &err, 0);
         if (len == 0) {
             break;
         }
         #if PPP_TRACE_IN_OUT
         mp_printf(&mp_plat_print, "ppp_in(n=%u,data=", len);
         for (size_t i = 0; i < len; ++i) {
             mp_printf(&mp_plat_print, "%02x:", buf[i]);
         }
         mp_printf(&mp_plat_print, ")\n");
         #endif
         pppos_input(self->pcb, (u8_t *)buf, len);
         total_len += len;
     }

     return MP_OBJ_NEW_SMALL_INT(total_len);
 }
 static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(network_ppp_poll_obj, 1, 2, network_ppp_poll);

 static void network_ppp_stream_uart_irq_enable(network_ppp_obj_t *self) {
     if (self->stream == mp_const_none) {
         return;
     }

     // Enable UART IRQ to call PPP.poll() when incoming data is ready.
     mp_obj_t dest[4];
     mp_load_method(self->stream, MP_QSTR_irq, dest);
     dest[2] = mp_obj_new_bound_meth(MP_OBJ_FROM_PTR(&network_ppp_poll_obj), MP_OBJ_FROM_PTR(self));
     dest[3] = mp_load_attr(self->stream, MP_QSTR_IRQ_RXIDLE);
     mp_call_method_n_kw(2, 0, dest);
 }

 static mp_obj_t network_ppp_config(size_t n_args, const mp_obj_t *args, mp_map_t *kwargs) {
     if (n_args != 1 && kwargs->used != 0) {
         mp_raise_TypeError(MP_ERROR_TEXT("either pos or kw args are allowed"));
     }
     network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);

     if (kwargs->used != 0) {
         for (size_t i = 0; i < kwargs->alloc; i++) {
             if (mp_map_slot_is_filled(kwargs, i)) {
                 switch (mp_obj_str_get_qstr(kwargs->table[i].key)) {
                     case MP_QSTR_stream: {
                         if (kwargs->table[i].value != mp_const_none) {
                             mp_get_stream_raise(kwargs->table[i].value, MP_STREAM_OP_READ | MP_STREAM_OP_WRITE);
                         }
                         if (self->state >= STATE_ACTIVE) {
                             network_ppp_stream_uart_irq_disable(self);
                         }
                         self->stream = kwargs->table[i].value;
                         if (self->state >= STATE_ACTIVE) {
                             network_ppp_stream_uart_irq_enable(self);
                         }
                         break;
                     }
                     default:
                         break;
                 }
             }
         }
         return mp_const_none;
     }

     if (n_args != 2) {
         mp_raise_TypeError(MP_ERROR_TEXT("can query only one param"));
     }

     mp_obj_t val = mp_const_none;

     switch (mp_obj_str_get_qstr(args[1])) {
         case MP_QSTR_stream: {
             val = self->stream;
             break;
         }
         default:
             mp_raise_ValueError(MP_ERROR_TEXT("unknown config param"));
     }

     return val;
 }
 static MP_DEFINE_CONST_FUN_OBJ_KW(network_ppp_config_obj, 1, network_ppp_config);

 static mp_obj_t network_ppp_status(mp_obj_t self_in) {
     network_ppp_obj_t *self = MP_OBJ_TO_PTR(self_in);
     if (self->state == STATE_ERROR) {
         return MP_OBJ_NEW_SMALL_INT(-self->error_code);
     } else {
         return MP_OBJ_NEW_SMALL_INT(self->state);
     }
 }
 static MP_DEFINE_CONST_FUN_OBJ_1(network_ppp_status_obj, network_ppp_status);

 static u32_t network_ppp_output_callback(ppp_pcb *pcb, const void *data, u32_t len, void *ctx) {
     network_ppp_obj_t *self = ctx;
     #if PPP_TRACE_IN_OUT
     mp_printf(&mp_plat_print, "ppp_out(n=%u,data=", len);
     for (size_t i = 0; i < len; ++i) {
         mp_printf(&mp_plat_print, "%02x:", ((const uint8_t *)data)[i]);
     }
     mp_printf(&mp_plat_print, ")\n");
     #endif
     mp_obj_t stream = self->stream;
     if (stream == mp_const_none) {
         return 0;
     }
     int err;
     // The return value from this output callback is the number of bytes written out.
     // If it's less than the requested number of bytes then lwIP will propagate out an error.
     return mp_stream_rw(stream, (void *)data, len, &err, MP_STREAM_RW_WRITE);
 }

 static mp_obj_t network_ppp_connect(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     enum { ARG_security, ARG_user, ARG_key };
     static const mp_arg_t allowed_args[] = {
         { MP_QSTR_security, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = PPPAUTHTYPE_NONE} },
         { MP_QSTR_user, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE} },
         { MP_QSTR_key, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE} },
     };

     mp_arg_val_t parsed_args[MP_ARRAY_SIZE(allowed_args)];
     mp_arg_parse_all(n_args - 1, args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, parsed_args);

     network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);

     if (self->state == STATE_INACTIVE) {
         self->pcb = pppos_create(&self->netif, network_ppp_output_callback, network_ppp_status_cb, self);
         if (self->pcb == NULL) {
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("pppos_create failed"));
         }
         self->state = STATE_ACTIVE;

         network_ppp_stream_uart_irq_enable(self);
     }

     if (self->state == STATE_CONNECTING || self->state == STATE_CONNECTED) {
         mp_raise_OSError(MP_EALREADY);
     }

     switch (parsed_args[ARG_security].u_int) {
         case PPPAUTHTYPE_NONE:
         case PPPAUTHTYPE_PAP:
         case PPPAUTHTYPE_CHAP:
             break;
         default:
             mp_raise_ValueError(MP_ERROR_TEXT("invalid auth"));
     }

     if (parsed_args[ARG_security].u_int != PPPAUTHTYPE_NONE) {
         const char *user_str = mp_obj_str_get_str(parsed_args[ARG_user].u_obj);
         const char *key_str = mp_obj_str_get_str(parsed_args[ARG_key].u_obj);
         ppp_set_auth(self->pcb, parsed_args[ARG_security].u_int, user_str, key_str);
     }

     ppp_set_default(self->pcb);

     ppp_set_usepeerdns(self->pcb, true);

     if (ppp_connect(self->pcb, 0) != ERR_OK) {
         mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("ppp_connect failed"));
     }

     self->state = STATE_CONNECTING;

     // Do a poll in case there is data waiting on the input stream.
     network_ppp_poll(1, args);

     return mp_const_none;
 }
 static MP_DEFINE_CONST_FUN_OBJ_KW(network_ppp_connect_obj, 1, network_ppp_connect);

 static mp_obj_t network_ppp_disconnect(mp_obj_t self_in) {
     network_ppp_obj_t *self = MP_OBJ_TO_PTR(self_in);
     if (self->state == STATE_CONNECTING || self->state == STATE_CONNECTED) {
         // Initiate close and wait for PPPERR_USER callback.
         ppp_close(self->pcb, 0);
     }
     return mp_const_none;
 }
 static MP_DEFINE_CONST_FUN_OBJ_1(network_ppp_disconnect_obj, network_ppp_disconnect);

 static mp_obj_t network_ppp_isconnected(mp_obj_t self_in) {
     network_ppp_obj_t *self = MP_OBJ_TO_PTR(self_in);
     return mp_obj_new_bool(self->state == STATE_CONNECTED);
 }
 static MP_DEFINE_CONST_FUN_OBJ_1(network_ppp_isconnected_obj, network_ppp_isconnected);

 static mp_obj_t network_ppp_ifconfig(size_t n_args, const mp_obj_t *args) {
     network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);
     return mod_network_nic_ifconfig(&self->netif, n_args - 1, args + 1);
 }
 static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(network_ppp_ifconfig_obj, 1, 2, network_ppp_ifconfig);

 static mp_obj_t network_ppp_ipconfig(size_t n_args, const mp_obj_t *args, mp_map_t *kwargs) {
     network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);
     return mod_network_nic_ipconfig(&self->netif, n_args - 1, args + 1, kwargs);
 }
 static MP_DEFINE_CONST_FUN_OBJ_KW(network_ppp_ipconfig_obj, 1, network_ppp_ipconfig);

 static const mp_rom_map_elem_t network_ppp_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR___del__), MP_ROM_PTR(&network_ppp___del___obj) },
     { MP_ROM_QSTR(MP_QSTR_config), MP_ROM_PTR(&network_ppp_config_obj) },
     { MP_ROM_QSTR(MP_QSTR_status), MP_ROM_PTR(&network_ppp_status_obj) },
     { MP_ROM_QSTR(MP_QSTR_connect), MP_ROM_PTR(&network_ppp_connect_obj) },
     { MP_ROM_QSTR(MP_QSTR_disconnect), MP_ROM_PTR(&network_ppp_disconnect_obj) },
     { MP_ROM_QSTR(MP_QSTR_isconnected), MP_ROM_PTR(&network_ppp_isconnected_obj) },
     { MP_ROM_QSTR(MP_QSTR_ifconfig), MP_ROM_PTR(&network_ppp_ifconfig_obj) },
     { MP_ROM_QSTR(MP_QSTR_ipconfig), MP_ROM_PTR(&network_ppp_ipconfig_obj) },
     { MP_ROM_QSTR(MP_QSTR_poll), MP_ROM_PTR(&network_ppp_poll_obj) },

     { MP_ROM_QSTR(MP_QSTR_SEC_NONE), MP_ROM_INT(PPPAUTHTYPE_NONE) },
     { MP_ROM_QSTR(MP_QSTR_SEC_PAP), MP_ROM_INT(PPPAUTHTYPE_PAP) },
     { MP_ROM_QSTR(MP_QSTR_SEC_CHAP), MP_ROM_INT(PPPAUTHTYPE_CHAP) },
 };
 static MP_DEFINE_CONST_DICT(network_ppp_locals_dict, network_ppp_locals_dict_table);

 MP_DEFINE_CONST_OBJ_TYPE(
     mp_network_ppp_lwip_type,
     MP_QSTR_PPP,
     MP_TYPE_FLAG_NONE,
     make_new, network_ppp_make_new,
     locals_dict, &network_ppp_locals_dict
     );

 #endif
	/*
	* This file is part of the MicroPython project, http://micropython.org/
	*
	* The MIT License (MIT)
	*
	* Copyright (c) 2024 Damien P. George
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*/

	// This file is intended to closely match ports/esp32/network_ppp.c. Changes can
	// and should probably be applied to both files. Compare them directly by using:
	// git diff --no-index extmod/network_ppp_lwip.c ports/esp32/network_ppp.c

	#include "py/runtime.h"
	#include "py/mphal.h"
	#include "py/stream.h"
	#include "extmod/modnetwork.h"

	#if MICROPY_PY_NETWORK_PPP_LWIP

	#include "lwip/dns.h"
	#include "netif/ppp/ppp.h"
	#include "netif/ppp/pppapi.h"
	#include "netif/ppp/pppos.h"

	// Enable this to see the serial data going between the PPP layer.
	#define PPP_TRACE_IN_OUT (0)

	typedef enum {
	STATE_INACTIVE,
	STATE_ACTIVE,
	STATE_ERROR,
	STATE_CONNECTING,
	STATE_CONNECTED,
	} network_ppp_state_t;

	typedef struct _network_ppp_obj_t {
	mp_obj_base_t base;
	network_ppp_state_t state;
	int error_code;
	mp_obj_t stream;
	ppp_pcb *pcb;
	struct netif netif;
	} network_ppp_obj_t;

	const mp_obj_type_t mp_network_ppp_lwip_type;

	static mp_obj_t network_ppp___del__(mp_obj_t self_in);

	static void network_ppp_stream_uart_irq_disable(network_ppp_obj_t *self) {
	if (self->stream == mp_const_none) {
	return;
	}

	// Disable UART IRQ.
	mp_obj_t dest[3];
	mp_load_method(self->stream, MP_QSTR_irq, dest);
	dest[2] = mp_const_none;
	mp_call_method_n_kw(1, 0, dest);
	}

	static void network_ppp_status_cb(ppp_pcb pcb, int err_code, void ctx) {
	network_ppp_obj_t *self = ctx;
	switch (err_code) {
	case PPPERR_NONE:
	self->state = STATE_CONNECTED;
	break;
	case PPPERR_USER:
	if (self->state >= STATE_ERROR) {
	// Indicate that we are no longer connected and thus
	// only need to free the PPP PCB, not close it.
	self->state = STATE_ACTIVE;
	}
	// Clean up the PPP PCB.
	network_ppp___del__(MP_OBJ_FROM_PTR(self));
	break;
	default:
	self->state = STATE_ERROR;
	self->error_code = err_code;
	break;
	}
	}

	static mp_obj_t network_ppp_make_new(const mp_obj_type_t type, size_t n_args, size_t n_kw, const mp_obj_t all_args) {
	mp_arg_check_num(n_args, n_kw, 1, 1, false);

	mp_obj_t stream = all_args[0];

	if (stream != mp_const_none) {
	mp_get_stream_raise(stream, MP_STREAM_OP_READ \| MP_STREAM_OP_WRITE);
	}

	network_ppp_obj_t *self = mp_obj_malloc_with_finaliser(network_ppp_obj_t, type);
	self->state = STATE_INACTIVE;
	self->stream = stream;
	self->pcb = NULL;

	return MP_OBJ_FROM_PTR(self);
	}

	static mp_obj_t network_ppp___del__(mp_obj_t self_in) {
	network_ppp_obj_t *self = MP_OBJ_TO_PTR(self_in);
	if (self->state >= STATE_ACTIVE) {
	if (self->state >= STATE_ERROR) {
	// Still connected over the stream.
	// Force the connection to close, with nocarrier=1.
	self->state = STATE_INACTIVE;
	ppp_close(self->pcb, 1);
	}
	network_ppp_stream_uart_irq_disable(self);
	// Free PPP PCB and reset state.
	self->state = STATE_INACTIVE;
	ppp_free(self->pcb);
	self->pcb = NULL;
	}
	return mp_const_none;
	}
	static MP_DEFINE_CONST_FUN_OBJ_1(network_ppp___del___obj, network_ppp___del__);

	static mp_obj_t network_ppp_poll(size_t n_args, const mp_obj_t *args) {
	network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);

	if (self->state <= STATE_ERROR) {
	return MP_OBJ_NEW_SMALL_INT(-MP_EPERM);
	}

	mp_int_t total_len = 0;
	mp_obj_t stream = self->stream;
	while (stream != mp_const_none) {
	uint8_t buf[256];
	int err;
	mp_uint_t len = mp_stream_rw(stream, buf, sizeof(buf), &err, 0);
	if (len == 0) {
	break;
	}
	#if PPP_TRACE_IN_OUT
	mp_printf(&mp_plat_print, "ppp_in(n=%u,data=", len);
	for (size_t i = 0; i < len; ++i) {
	mp_printf(&mp_plat_print, "%02x:", buf[i]);
	}
	mp_printf(&mp_plat_print, ")\n");
	#endif
	pppos_input(self->pcb, (u8_t *)buf, len);
	total_len += len;
	}

	return MP_OBJ_NEW_SMALL_INT(total_len);
	}
	static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(network_ppp_poll_obj, 1, 2, network_ppp_poll);

	static void network_ppp_stream_uart_irq_enable(network_ppp_obj_t *self) {
	if (self->stream == mp_const_none) {
	return;
	}

	// Enable UART IRQ to call PPP.poll() when incoming data is ready.
	mp_obj_t dest[4];
	mp_load_method(self->stream, MP_QSTR_irq, dest);
	dest[2] = mp_obj_new_bound_meth(MP_OBJ_FROM_PTR(&network_ppp_poll_obj), MP_OBJ_FROM_PTR(self));
	dest[3] = mp_load_attr(self->stream, MP_QSTR_IRQ_RXIDLE);
	mp_call_method_n_kw(2, 0, dest);
	}

	static mp_obj_t network_ppp_config(size_t n_args, const mp_obj_t args, mp_map_t kwargs) {
	if (n_args != 1 && kwargs->used != 0) {
	mp_raise_TypeError(MP_ERROR_TEXT("either pos or kw args are allowed"));
	}
	network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);

	if (kwargs->used != 0) {
	for (size_t i = 0; i < kwargs->alloc; i++) {
	if (mp_map_slot_is_filled(kwargs, i)) {
	switch (mp_obj_str_get_qstr(kwargs->table[i].key)) {
	case MP_QSTR_stream: {
	if (kwargs->table[i].value != mp_const_none) {
	mp_get_stream_raise(kwargs->table[i].value, MP_STREAM_OP_READ \| MP_STREAM_OP_WRITE);
	}
	if (self->state >= STATE_ACTIVE) {
	network_ppp_stream_uart_irq_disable(self);
	}
	self->stream = kwargs->table[i].value;
	if (self->state >= STATE_ACTIVE) {
	network_ppp_stream_uart_irq_enable(self);
	}
	break;
	}
	default:
	break;
	}
	}
	}
	return mp_const_none;
	}

	if (n_args != 2) {
	mp_raise_TypeError(MP_ERROR_TEXT("can query only one param"));
	}

	mp_obj_t val = mp_const_none;

	switch (mp_obj_str_get_qstr(args[1])) {
	case MP_QSTR_stream: {
	val = self->stream;
	break;
	}
	default:
	mp_raise_ValueError(MP_ERROR_TEXT("unknown config param"));
	}

	return val;
	}
	static MP_DEFINE_CONST_FUN_OBJ_KW(network_ppp_config_obj, 1, network_ppp_config);

	static mp_obj_t network_ppp_status(mp_obj_t self_in) {
	network_ppp_obj_t *self = MP_OBJ_TO_PTR(self_in);
	if (self->state == STATE_ERROR) {
	return MP_OBJ_NEW_SMALL_INT(-self->error_code);
	} else {
	return MP_OBJ_NEW_SMALL_INT(self->state);
	}
	}
	static MP_DEFINE_CONST_FUN_OBJ_1(network_ppp_status_obj, network_ppp_status);

	static u32_t network_ppp_output_callback(ppp_pcb pcb, const void data, u32_t len, void *ctx) {
	network_ppp_obj_t *self = ctx;
	#if PPP_TRACE_IN_OUT
	mp_printf(&mp_plat_print, "ppp_out(n=%u,data=", len);
	for (size_t i = 0; i < len; ++i) {
	mp_printf(&mp_plat_print, "%02x:", ((const uint8_t *)data)[i]);
	}
	mp_printf(&mp_plat_print, ")\n");
	#endif
	mp_obj_t stream = self->stream;
	if (stream == mp_const_none) {
	return 0;
	}
	int err;
	// The return value from this output callback is the number of bytes written out.
	// If it's less than the requested number of bytes then lwIP will propagate out an error.
	return mp_stream_rw(stream, (void *)data, len, &err, MP_STREAM_RW_WRITE);
	}

	static mp_obj_t network_ppp_connect(size_t n_args, const mp_obj_t args, mp_map_t kw_args) {
	enum { ARG_security, ARG_user, ARG_key };
	static const mp_arg_t allowed_args[] = {
	{ MP_QSTR_security, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = PPPAUTHTYPE_NONE} },
	{ MP_QSTR_user, MP_ARG_KW_ONLY \| MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE} },
	{ MP_QSTR_key, MP_ARG_KW_ONLY \| MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE} },
	};

	mp_arg_val_t parsed_args[MP_ARRAY_SIZE(allowed_args)];
	mp_arg_parse_all(n_args - 1, args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, parsed_args);

	network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);

	if (self->state == STATE_INACTIVE) {
	self->pcb = pppos_create(&self->netif, network_ppp_output_callback, network_ppp_status_cb, self);
	if (self->pcb == NULL) {
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("pppos_create failed"));
	}
	self->state = STATE_ACTIVE;

	network_ppp_stream_uart_irq_enable(self);
	}

	if (self->state == STATE_CONNECTING \|\| self->state == STATE_CONNECTED) {
	mp_raise_OSError(MP_EALREADY);
	}

	switch (parsed_args[ARG_security].u_int) {
	case PPPAUTHTYPE_NONE:
	case PPPAUTHTYPE_PAP:
	case PPPAUTHTYPE_CHAP:
	break;
	default:
	mp_raise_ValueError(MP_ERROR_TEXT("invalid auth"));
	}

	if (parsed_args[ARG_security].u_int != PPPAUTHTYPE_NONE) {
	const char *user_str = mp_obj_str_get_str(parsed_args[ARG_user].u_obj);
	const char *key_str = mp_obj_str_get_str(parsed_args[ARG_key].u_obj);
	ppp_set_auth(self->pcb, parsed_args[ARG_security].u_int, user_str, key_str);
	}

	ppp_set_default(self->pcb);

	ppp_set_usepeerdns(self->pcb, true);

	if (ppp_connect(self->pcb, 0) != ERR_OK) {
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("ppp_connect failed"));
	}

	self->state = STATE_CONNECTING;

	// Do a poll in case there is data waiting on the input stream.
	network_ppp_poll(1, args);

	return mp_const_none;
	}
	static MP_DEFINE_CONST_FUN_OBJ_KW(network_ppp_connect_obj, 1, network_ppp_connect);

	static mp_obj_t network_ppp_disconnect(mp_obj_t self_in) {
	network_ppp_obj_t *self = MP_OBJ_TO_PTR(self_in);
	if (self->state == STATE_CONNECTING \|\| self->state == STATE_CONNECTED) {
	// Initiate close and wait for PPPERR_USER callback.
	ppp_close(self->pcb, 0);
	}
	return mp_const_none;
	}
	static MP_DEFINE_CONST_FUN_OBJ_1(network_ppp_disconnect_obj, network_ppp_disconnect);

	static mp_obj_t network_ppp_isconnected(mp_obj_t self_in) {
	network_ppp_obj_t *self = MP_OBJ_TO_PTR(self_in);
	return mp_obj_new_bool(self->state == STATE_CONNECTED);
	}
	static MP_DEFINE_CONST_FUN_OBJ_1(network_ppp_isconnected_obj, network_ppp_isconnected);

	static mp_obj_t network_ppp_ifconfig(size_t n_args, const mp_obj_t *args) {
	network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);
	return mod_network_nic_ifconfig(&self->netif, n_args - 1, args + 1);
	}
	static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(network_ppp_ifconfig_obj, 1, 2, network_ppp_ifconfig);

	static mp_obj_t network_ppp_ipconfig(size_t n_args, const mp_obj_t args, mp_map_t kwargs) {
	network_ppp_obj_t *self = MP_OBJ_TO_PTR(args[0]);
	return mod_network_nic_ipconfig(&self->netif, n_args - 1, args + 1, kwargs);
	}
	static MP_DEFINE_CONST_FUN_OBJ_KW(network_ppp_ipconfig_obj, 1, network_ppp_ipconfig);

	static const mp_rom_map_elem_t network_ppp_locals_dict_table[] = {
	{ MP_ROM_QSTR(MP_QSTR___del__), MP_ROM_PTR(&network_ppp___del___obj) },
	{ MP_ROM_QSTR(MP_QSTR_config), MP_ROM_PTR(&network_ppp_config_obj) },
	{ MP_ROM_QSTR(MP_QSTR_status), MP_ROM_PTR(&network_ppp_status_obj) },
	{ MP_ROM_QSTR(MP_QSTR_connect), MP_ROM_PTR(&network_ppp_connect_obj) },
	{ MP_ROM_QSTR(MP_QSTR_disconnect), MP_ROM_PTR(&network_ppp_disconnect_obj) },
	{ MP_ROM_QSTR(MP_QSTR_isconnected), MP_ROM_PTR(&network_ppp_isconnected_obj) },
	{ MP_ROM_QSTR(MP_QSTR_ifconfig), MP_ROM_PTR(&network_ppp_ifconfig_obj) },
	{ MP_ROM_QSTR(MP_QSTR_ipconfig), MP_ROM_PTR(&network_ppp_ipconfig_obj) },
	{ MP_ROM_QSTR(MP_QSTR_poll), MP_ROM_PTR(&network_ppp_poll_obj) },

	{ MP_ROM_QSTR(MP_QSTR_SEC_NONE), MP_ROM_INT(PPPAUTHTYPE_NONE) },
	{ MP_ROM_QSTR(MP_QSTR_SEC_PAP), MP_ROM_INT(PPPAUTHTYPE_PAP) },
	{ MP_ROM_QSTR(MP_QSTR_SEC_CHAP), MP_ROM_INT(PPPAUTHTYPE_CHAP) },
	};
	static MP_DEFINE_CONST_DICT(network_ppp_locals_dict, network_ppp_locals_dict_table);

	MP_DEFINE_CONST_OBJ_TYPE(
	mp_network_ppp_lwip_type,
	MP_QSTR_PPP,
	MP_TYPE_FLAG_NONE,
	make_new, network_ppp_make_new,
	locals_dict, &network_ppp_locals_dict
	);

	#endif