circuitpython/extmod/modussl_mbedtls.c

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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2016 Linaro Ltd.
*
* 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.
*/
#include "py/mpconfig.h"
#if MICROPY_PY_USSL && MICROPY_SSL_MBEDTLS
#include <stdio.h>
#include <string.h>
#include <errno.h> // needed because mp_is_nonblocking_error uses system error codes
#include "py/runtime.h"
#include "py/stream.h"
// mbedtls_time_t
#include "mbedtls/platform.h"
#include "mbedtls/net.h"
#include "mbedtls/ssl.h"
#include "mbedtls/x509_crt.h"
#include "mbedtls/pk.h"
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/debug.h"
typedef struct _mp_obj_ssl_socket_t {
mp_obj_base_t base;
mp_obj_t sock;
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_ssl_context ssl;
mbedtls_ssl_config conf;
mbedtls_x509_crt cacert;
mbedtls_x509_crt cert;
mbedtls_pk_context pkey;
} mp_obj_ssl_socket_t;
struct ssl_args {
mp_arg_val_t key;
mp_arg_val_t cert;
mp_arg_val_t server_side;
mp_arg_val_t server_hostname;
};
STATIC const mp_obj_type_t ussl_socket_type;
#ifdef MBEDTLS_DEBUG_C
STATIC void mbedtls_debug(void *ctx, int level, const char *file, int line, const char *str) {
(void)ctx;
(void)level;
printf("DBG:%s:%04d: %s\n", file, line, str);
}
#endif
STATIC int _mbedtls_ssl_send(void *ctx, const byte *buf, size_t len) {
mp_obj_t sock = *(mp_obj_t*)ctx;
const mp_stream_p_t *sock_stream = mp_get_stream(sock);
int err;
mp_uint_t out_sz = sock_stream->write(sock, buf, len, &err);
if (out_sz == MP_STREAM_ERROR) {
if (mp_is_nonblocking_error(err)) {
return MBEDTLS_ERR_SSL_WANT_WRITE;
}
return -err;
} else {
return out_sz;
}
}
STATIC int _mbedtls_ssl_recv(void *ctx, byte *buf, size_t len) {
mp_obj_t sock = *(mp_obj_t*)ctx;
const mp_stream_p_t *sock_stream = mp_get_stream(sock);
int err;
mp_uint_t out_sz = sock_stream->read(sock, buf, len, &err);
if (out_sz == MP_STREAM_ERROR) {
if (mp_is_nonblocking_error(err)) {
return MBEDTLS_ERR_SSL_WANT_READ;
}
return -err;
} else {
return out_sz;
}
}
STATIC mp_obj_ssl_socket_t *socket_new(mp_obj_t sock, struct ssl_args *args) {
// Verify the socket object has the full stream protocol
mp_get_stream_raise(sock, MP_STREAM_OP_READ | MP_STREAM_OP_WRITE | MP_STREAM_OP_IOCTL);
#if MICROPY_PY_USSL_FINALISER
mp_obj_ssl_socket_t *o = m_new_obj_with_finaliser(mp_obj_ssl_socket_t);
#else
mp_obj_ssl_socket_t *o = m_new_obj(mp_obj_ssl_socket_t);
#endif
o->base.type = &ussl_socket_type;
o->sock = sock;
int ret;
mbedtls_ssl_init(&o->ssl);
mbedtls_ssl_config_init(&o->conf);
mbedtls_x509_crt_init(&o->cacert);
mbedtls_x509_crt_init(&o->cert);
mbedtls_pk_init(&o->pkey);
mbedtls_ctr_drbg_init(&o->ctr_drbg);
#ifdef MBEDTLS_DEBUG_C
// Debug level (0-4)
mbedtls_debug_set_threshold(0);
#endif
mbedtls_entropy_init(&o->entropy);
const byte seed[] = "upy";
ret = mbedtls_ctr_drbg_seed(&o->ctr_drbg, mbedtls_entropy_func, &o->entropy, seed, sizeof(seed));
if (ret != 0) {
goto cleanup;
}
ret = mbedtls_ssl_config_defaults(&o->conf,
args->server_side.u_bool ? MBEDTLS_SSL_IS_SERVER : MBEDTLS_SSL_IS_CLIENT,
MBEDTLS_SSL_TRANSPORT_STREAM,
MBEDTLS_SSL_PRESET_DEFAULT);
if (ret != 0) {
goto cleanup;
}
mbedtls_ssl_conf_authmode(&o->conf, MBEDTLS_SSL_VERIFY_NONE);
mbedtls_ssl_conf_rng(&o->conf, mbedtls_ctr_drbg_random, &o->ctr_drbg);
#ifdef MBEDTLS_DEBUG_C
mbedtls_ssl_conf_dbg(&o->conf, mbedtls_debug, NULL);
#endif
ret = mbedtls_ssl_setup(&o->ssl, &o->conf);
if (ret != 0) {
goto cleanup;
}
if (args->server_hostname.u_obj != mp_const_none) {
const char *sni = mp_obj_str_get_str(args->server_hostname.u_obj);
ret = mbedtls_ssl_set_hostname(&o->ssl, sni);
if (ret != 0) {
goto cleanup;
}
}
mbedtls_ssl_set_bio(&o->ssl, &o->sock, _mbedtls_ssl_send, _mbedtls_ssl_recv, NULL);
if (args->key.u_obj != MP_OBJ_NULL) {
size_t key_len;
const byte *key = (const byte*)mp_obj_str_get_data(args->key.u_obj, &key_len);
// len should include terminating null
ret = mbedtls_pk_parse_key(&o->pkey, key, key_len + 1, NULL, 0);
assert(ret == 0);
size_t cert_len;
const byte *cert = (const byte*)mp_obj_str_get_data(args->cert.u_obj, &cert_len);
// len should include terminating null
ret = mbedtls_x509_crt_parse(&o->cert, cert, cert_len + 1);
assert(ret == 0);
ret = mbedtls_ssl_conf_own_cert(&o->conf, &o->cert, &o->pkey);
assert(ret == 0);
}
while ((ret = mbedtls_ssl_handshake(&o->ssl)) != 0) {
if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
printf("mbedtls_ssl_handshake error: -%x\n", -ret);
goto cleanup;
}
}
return o;
cleanup:
mbedtls_pk_free(&o->pkey);
mbedtls_x509_crt_free(&o->cert);
mbedtls_x509_crt_free(&o->cacert);
mbedtls_ssl_free(&o->ssl);
mbedtls_ssl_config_free(&o->conf);
mbedtls_ctr_drbg_free(&o->ctr_drbg);
mbedtls_entropy_free(&o->entropy);
if (ret == MBEDTLS_ERR_SSL_ALLOC_FAILED) {
mp_raise_OSError(MP_ENOMEM);
} else {
mp_raise_OSError(MP_EIO);
}
}
STATIC mp_obj_t mod_ssl_getpeercert(mp_obj_t o_in, mp_obj_t binary_form) {
mp_obj_ssl_socket_t *o = MP_OBJ_TO_PTR(o_in);
if (!mp_obj_is_true(binary_form)) {
mp_raise_NotImplementedError(NULL);
}
const mbedtls_x509_crt* peer_cert = mbedtls_ssl_get_peer_cert(&o->ssl);
return mp_obj_new_bytes(peer_cert->raw.p, peer_cert->raw.len);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_ssl_getpeercert_obj, mod_ssl_getpeercert);
STATIC void socket_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
(void)kind;
mp_obj_ssl_socket_t *self = MP_OBJ_TO_PTR(self_in);
mp_printf(print, "<_SSLSocket %p>", self);
}
STATIC mp_uint_t socket_read(mp_obj_t o_in, void *buf, mp_uint_t size, int *errcode) {
mp_obj_ssl_socket_t *o = MP_OBJ_TO_PTR(o_in);
int ret = mbedtls_ssl_read(&o->ssl, buf, size);
if (ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY) {
// end of stream
return 0;
}
if (ret >= 0) {
return ret;
}
if (ret == MBEDTLS_ERR_SSL_WANT_READ) {
ret = MP_EWOULDBLOCK;
}
*errcode = ret;
return MP_STREAM_ERROR;
}
STATIC mp_uint_t socket_write(mp_obj_t o_in, const void *buf, mp_uint_t size, int *errcode) {
mp_obj_ssl_socket_t *o = MP_OBJ_TO_PTR(o_in);
int ret = mbedtls_ssl_write(&o->ssl, buf, size);
if (ret >= 0) {
return ret;
}
if (ret == MBEDTLS_ERR_SSL_WANT_WRITE) {
ret = MP_EWOULDBLOCK;
}
*errcode = ret;
return MP_STREAM_ERROR;
}
STATIC mp_obj_t socket_setblocking(mp_obj_t self_in, mp_obj_t flag_in) {
mp_obj_ssl_socket_t *o = MP_OBJ_TO_PTR(self_in);
mp_obj_t sock = o->sock;
mp_obj_t dest[3];
mp_load_method(sock, MP_QSTR_setblocking, dest);
dest[2] = flag_in;
return mp_call_method_n_kw(1, 0, dest);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(socket_setblocking_obj, socket_setblocking);
STATIC mp_uint_t socket_ioctl(mp_obj_t o_in, mp_uint_t request, uintptr_t arg, int *errcode) {
mp_obj_ssl_socket_t *self = MP_OBJ_TO_PTR(o_in);
(void)arg;
switch (request) {
case MP_STREAM_CLOSE:
mbedtls_pk_free(&self->pkey);
mbedtls_x509_crt_free(&self->cert);
mbedtls_x509_crt_free(&self->cacert);
mbedtls_ssl_free(&self->ssl);
mbedtls_ssl_config_free(&self->conf);
mbedtls_ctr_drbg_free(&self->ctr_drbg);
mbedtls_entropy_free(&self->entropy);
mp_stream_close(self->sock);
return 0;
default:
*errcode = MP_EINVAL;
return MP_STREAM_ERROR;
}
}
STATIC const mp_rom_map_elem_t ussl_socket_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
{ MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
{ MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
{ MP_ROM_QSTR(MP_QSTR_setblocking), MP_ROM_PTR(&socket_setblocking_obj) },
{ MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&mp_stream_close_obj) },
#if MICROPY_PY_USSL_FINALISER
{ MP_ROM_QSTR(MP_QSTR___del__), MP_ROM_PTR(&mp_stream_close_obj) },
#endif
{ MP_ROM_QSTR(MP_QSTR_getpeercert), MP_ROM_PTR(&mod_ssl_getpeercert_obj) },
};
STATIC MP_DEFINE_CONST_DICT(ussl_socket_locals_dict, ussl_socket_locals_dict_table);
STATIC const mp_stream_p_t ussl_socket_stream_p = {
protocols: Allow them to be (optionally) type-safe Protocols are nice, but there is no way for C code to verify whether a type's "protocol" structure actually implements some particular protocol. As a result, you can pass an object that implements the "vfs" protocol to one that expects the "stream" protocol, and the opposite of awesomeness ensues. This patch adds an OPTIONAL (but enabled by default) protocol identifier as the first member of any protocol structure. This identifier is simply a unique QSTR chosen by the protocol designer and used by each protocol implementer. When checking for protocol support, instead of just checking whether the object's type has a non-NULL protocol field, use `mp_proto_get` which implements the protocol check when possible. The existing protocols are now named: protocol_framebuf protocol_i2c protocol_pin protocol_stream protocol_spi protocol_vfs (most of these are unused in CP and are just inherited from MP; vfs and stream are definitely used though) I did not find any crashing examples, but here's one to give a flavor of what is improved, using `micropython_coverage`. Before the change, the vfs "ioctl" protocol is invoked, and the result is not intelligible as json (but it could have resulted in a hard fault, potentially): >>> import uos, ujson >>> u = uos.VfsPosix('/tmp') >>> ujson.load(u) Traceback (most recent call last): File "<stdin>", line 1, in <module> ValueError: syntax error in JSON After the change, the vfs object is correctly detected as not supporting the stream protocol: >>> ujson.load(p) Traceback (most recent call last): File "<stdin>", line 1, in <module> OSError: stream operation not supported
2019-12-03 15:50:37 -05:00
MP_PROTO_IMPLEMENT(MP_QSTR_protocol_stream)
.read = socket_read,
.write = socket_write,
.ioctl = socket_ioctl,
};
STATIC const mp_obj_type_t ussl_socket_type = {
{ &mp_type_type },
// Save on qstr's, reuse same as for module
.name = MP_QSTR_ussl,
.print = socket_print,
.getiter = NULL,
.iternext = NULL,
.protocol = &ussl_socket_stream_p,
.locals_dict = (void*)&ussl_socket_locals_dict,
};
STATIC mp_obj_t mod_ssl_wrap_socket(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
// TODO: Implement more args
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_key, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_cert, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_server_side, MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = false} },
{ MP_QSTR_server_hostname, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
};
// TODO: Check that sock implements stream protocol
mp_obj_t sock = pos_args[0];
struct ssl_args args;
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args,
MP_ARRAY_SIZE(allowed_args), allowed_args, (mp_arg_val_t*)&args);
return MP_OBJ_FROM_PTR(socket_new(sock, &args));
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mod_ssl_wrap_socket_obj, 1, mod_ssl_wrap_socket);
STATIC const mp_rom_map_elem_t mp_module_ssl_globals_table[] = {
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_ussl) },
{ MP_ROM_QSTR(MP_QSTR_wrap_socket), MP_ROM_PTR(&mod_ssl_wrap_socket_obj) },
};
STATIC MP_DEFINE_CONST_DICT(mp_module_ssl_globals, mp_module_ssl_globals_table);
const mp_obj_module_t mp_module_ussl = {
.base = { &mp_type_module },
.globals = (mp_obj_dict_t*)&mp_module_ssl_globals,
};
#endif // MICROPY_PY_USSL