Add ESP certificate bundle feature

Adds the ESP certificate bundle feature that enables users to bundle a
root certificate bundle together with their application.

Default bundle includes all Mozilla root certificates

Closes IDF-296
This commit is contained in:
Marius Vikhammer
2019-09-29 18:04:34 +08:00
parent 8e1442f0e7
commit 947e3e94ed
48 changed files with 5030 additions and 147 deletions

View File

@@ -2,5 +2,4 @@
#
# (If this was a component, we would set COMPONENT_EMBED_TXTFILES here.)
idf_component_register(SRCS "https_mbedtls_example_main.c"
INCLUDE_DIRS "."
EMBED_TXTFILES server_root_cert.pem)
INCLUDE_DIRS ".")

View File

@@ -3,8 +3,3 @@
#
# (Uses default behaviour of compiling all source files in directory, adding 'include' to include path.)
# embed files from the "certs" directory as binary data symbols
# in the app
COMPONENT_EMBED_TXTFILES := server_root_cert.pem

View File

@@ -47,6 +47,7 @@
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/error.h"
#include "mbedtls/certs.h"
#include "esp_crt_bundle.h"
/* Constants that aren't configurable in menuconfig */
@@ -61,19 +62,6 @@ static const char *REQUEST = "GET " WEB_URL " HTTP/1.0\r\n"
"User-Agent: esp-idf/1.0 esp32\r\n"
"\r\n";
/* Root cert for howsmyssl.com, taken from server_root_cert.pem
The PEM file was extracted from the output of this command:
openssl s_client -showcerts -connect www.howsmyssl.com:443 </dev/null
The CA root cert is the last cert given in the chain of certs.
To embed it in the app binary, the PEM file is named
in the component.mk COMPONENT_EMBED_TXTFILES variable.
*/
extern const uint8_t server_root_cert_pem_start[] asm("_binary_server_root_cert_pem_start");
extern const uint8_t server_root_cert_pem_end[] asm("_binary_server_root_cert_pem_end");
static void https_get_task(void *pvParameters)
{
@@ -102,14 +90,13 @@ static void https_get_task(void *pvParameters)
abort();
}
ESP_LOGI(TAG, "Loading the CA root certificate...");
ESP_LOGI(TAG, "Attaching the certificate bundle...");
ret = mbedtls_x509_crt_parse(&cacert, server_root_cert_pem_start,
server_root_cert_pem_end-server_root_cert_pem_start);
ret = esp_crt_bundle_attach(&conf);
if(ret < 0)
{
ESP_LOGE(TAG, "mbedtls_x509_crt_parse returned -0x%x\n\n", -ret);
ESP_LOGE(TAG, "esp_crt_bundle_attach returned -0x%x\n\n", -ret);
abort();
}

View File

@@ -1,27 +0,0 @@
-----BEGIN CERTIFICATE-----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AAOCAQEA3TPXEfNjWDjdGBX7CVW+dla5cEilaUcne8IkCJLxWh9KEik3JHRRHGJo
uM2VcGfl96S8TihRzZvoroed6ti6WqEBmtzw3Wodatg+VyOeph4EYpr/1wXKtx8/
wApIvJSwtmVi4MFU5aMqrSDE6ea73Mj2tcMyo5jMd6jmeWUHK8so/joWUoHOUgwu
X4Po1QYz+3dszkDqMp4fklxBwXRsW10KXzPMTZ+sOPAveyxindmjkW8lGy+QsRlG
PfZ+G6Z6h7mjem0Y+iWlkYcV4PIWL1iwBi8saCbGS5jN2p8M+X+Q7UNKEkROb3N6
KOqkqm57TH2H3eDJAkSnh6/DNFu0Qg==
-----END CERTIFICATE-----

View File

@@ -2,5 +2,4 @@
#
# (If this was a component, we would set COMPONENT_EMBED_TXTFILES here.)
idf_component_register(SRCS "https_request_example_main.c"
INCLUDE_DIRS "."
EMBED_TXTFILES server_root_cert.pem)
INCLUDE_DIRS ".")

View File

@@ -3,8 +3,4 @@
#
# (Uses default behaviour of compiling all source files in directory, adding 'include' to include path.)
# embed files from the "certs" directory as binary data symbols
# in the app
COMPONENT_EMBED_TXTFILES := server_root_cert.pem

View File

@@ -41,6 +41,7 @@
#include "lwip/dns.h"
#include "esp_tls.h"
#include "esp_crt_bundle.h"
/* Constants that aren't configurable in menuconfig */
#define WEB_SERVER "www.howsmyssl.com"
@@ -54,20 +55,6 @@ static const char *REQUEST = "GET " WEB_URL " HTTP/1.0\r\n"
"User-Agent: esp-idf/1.0 esp32\r\n"
"\r\n";
/* Root cert for howsmyssl.com, taken from server_root_cert.pem
The PEM file was extracted from the output of this command:
openssl s_client -showcerts -connect www.howsmyssl.com:443 </dev/null
The CA root cert is the last cert given in the chain of certs.
To embed it in the app binary, the PEM file is named
in the component.mk COMPONENT_EMBED_TXTFILES variable.
*/
extern const uint8_t server_root_cert_pem_start[] asm("_binary_server_root_cert_pem_start");
extern const uint8_t server_root_cert_pem_end[] asm("_binary_server_root_cert_pem_end");
static void https_get_task(void *pvParameters)
{
char buf[512];
@@ -75,23 +62,22 @@ static void https_get_task(void *pvParameters)
while(1) {
esp_tls_cfg_t cfg = {
.cacert_buf = server_root_cert_pem_start,
.cacert_bytes = server_root_cert_pem_end - server_root_cert_pem_start,
.crt_bundle_attach = esp_crt_bundle_attach,
};
struct esp_tls *tls = esp_tls_conn_http_new(WEB_URL, &cfg);
if(tls != NULL) {
ESP_LOGI(TAG, "Connection established...");
} else {
ESP_LOGE(TAG, "Connection failed...");
goto exit;
}
size_t written_bytes = 0;
do {
ret = esp_tls_conn_write(tls,
REQUEST + written_bytes,
ret = esp_tls_conn_write(tls,
REQUEST + written_bytes,
strlen(REQUEST) - written_bytes);
if (ret >= 0) {
ESP_LOGI(TAG, "%d bytes written", ret);
@@ -109,10 +95,10 @@ static void https_get_task(void *pvParameters)
len = sizeof(buf) - 1;
bzero(buf, sizeof(buf));
ret = esp_tls_conn_read(tls, (char *)buf, len);
if(ret == ESP_TLS_ERR_SSL_WANT_WRITE || ret == ESP_TLS_ERR_SSL_WANT_READ)
continue;
if(ret < 0)
{
ESP_LOGE(TAG, "esp_tls_conn_read returned -0x%x", -ret);
@@ -134,7 +120,7 @@ static void https_get_task(void *pvParameters)
} while(1);
exit:
esp_tls_conn_delete(tls);
esp_tls_conn_delete(tls);
putchar('\n'); // JSON output doesn't have a newline at end
static int request_count;

View File

@@ -1,27 +0,0 @@
-----BEGIN CERTIFICATE-----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AQH/BAgwBgEB/wIBADAOBgNVHQ8BAf8EBAMCAYYwfwYIKwYBBQUHAQEEczBxMDIG
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AAOCAQEA3TPXEfNjWDjdGBX7CVW+dla5cEilaUcne8IkCJLxWh9KEik3JHRRHGJo
uM2VcGfl96S8TihRzZvoroed6ti6WqEBmtzw3Wodatg+VyOeph4EYpr/1wXKtx8/
wApIvJSwtmVi4MFU5aMqrSDE6ea73Mj2tcMyo5jMd6jmeWUHK8so/joWUoHOUgwu
X4Po1QYz+3dszkDqMp4fklxBwXRsW10KXzPMTZ+sOPAveyxindmjkW8lGy+QsRlG
PfZ+G6Z6h7mjem0Y+iWlkYcV4PIWL1iwBi8saCbGS5jN2p8M+X+Q7UNKEkROb3N6
KOqkqm57TH2H3eDJAkSnh6/DNFu0Qg==
-----END CERTIFICATE-----

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@@ -0,0 +1,10 @@
# The following five lines of boilerplate have to be in your project's
# CMakeLists in this exact order for cmake to work correctly
cmake_minimum_required(VERSION 3.5)
# (Not part of the boilerplate)
# This example uses an extra component for common functions such as Wi-Fi and Ethernet connection.
set(EXTRA_COMPONENT_DIRS $ENV{IDF_PATH}/examples/common_components/protocol_examples_common)
include($ENV{IDF_PATH}/tools/cmake/project.cmake)
project(https_x509_bundle)

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@@ -0,0 +1,11 @@
#
# This is a project Makefile. It is assumed the directory this Makefile resides in is a
# project subdirectory.
#
PROJECT_NAME := https_x509_bundle
EXTRA_COMPONENT_DIRS = $(IDF_PATH)/examples/common_components/protocol_examples_common
include $(IDF_PATH)/make/project.mk

View File

@@ -0,0 +1,45 @@
# HTTPS x509 Bundle Example
This example shows how to use the ESP certificate bundle utility to embed a bundle of x509 certificates and use them to
establish a simple HTTPS connection over a secure connection. The path of the certificates are specified using menuconfig.
See the README.md file in the upper level 'examples' directory for more information about examples.
## Example workflow
- ESP TLS is initialized with the certificate bundle option enabled.
- The application loops through the given URLs, establishing a secure TLS connection to all of them, verifying the server certificate included.
### Configure the project
* Open the project configuration menu (`idf.py menuconfig`)
* Configure Wi-Fi or Ethernet under "Example Connection Configuration" menu. See "Establishing Wi-Fi or Ethernet Connection" section in [examples/protocols/README.md](../README.md) for more details.
* When using Make build system, set `Default serial port` under `Serial flasher config`.
* If using a different folder than `certs` for storing certificates then update `Custom Certificate Bundle Path` under `Component config` - `mbedTLS` - `Certificate Bundle`
### Build and Flash
Build the project and flash it to the board, then run monitor tool to view serial output:
```
idf.py -p PORT flash monitor
```
(To exit the serial monitor, type ``Ctrl-]``.)
See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.
## Example Output
```
I (0) cpu_start: Starting scheduler on APP CPU.
I (491) system_api: Base MAC address is not set, read default base MAC address from BLK0 of EFUSE
I (4051) example_connect: Ethernet Link Up
I (5971) tcpip_adapter: eth ip: 192.168.2.137, mask: 255.255.255.0, gw: 192.168.2.2
I (5971) example_connect: Connected to Ethernet
I (5971) example_connect: IPv4 address: 192.168.2.137
I (5971) example_connect: IPv6 address: fe80:0000:0000:0000:bedd:c2ff:fed4:a92b
I (5981) example: Connecting to 2 URLs
I (8371) example: Connection established to https://www.howsmyssl.com/a/check
I (11821) example: Connection established to https://espressif.com
I (12821) example: Completed 2 connections
I (12821) example: Starting over again...

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@@ -0,0 +1,25 @@
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

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@@ -0,0 +1,40 @@
import re
import os
import sys
try:
import IDF
except ImportError:
# this is a test case write with tiny-test-fw.
# to run test cases outside tiny-test-fw,
# we need to set environment variable `TEST_FW_PATH`,
# then get and insert `TEST_FW_PATH` to sys path before import FW module
test_fw_path = os.getenv("TEST_FW_PATH")
if test_fw_path and test_fw_path not in sys.path:
sys.path.insert(0, test_fw_path)
import IDF
@IDF.idf_example_test(env_tag="Example_WIFI", ignore=True)
def test_examples_protocol_https_x509_bundle(env, extra_data):
"""
steps: |
1. join AP
2. connect to multiple URLs
3. send http request
"""
dut1 = env.get_dut("https_x509_bundle", "examples/protocols/https_x509_bundle")
# check and log bin size
binary_file = os.path.join(dut1.app.binary_path, "https_x509_bundle.bin")
bin_size = os.path.getsize(binary_file)
IDF.log_performance("https_x509_bundle_bin_size", "{}KB".format(bin_size // 1024))
IDF.check_performance("https_x509_bundle_bin_size", bin_size // 1024)
# start test
dut1.start_app()
num_URLS = dut1.expect(re.compile(r"Connecting to (\d+) URLs"), timeout=30)
dut1.expect(re.compile(r"Connection established to ([\s\S]*)"), timeout=30)
dut1.expect("Completed {} connections".format(num_URLS[0]), timeout=60)
if __name__ == '__main__':
test_examples_protocol_https_x509_bundle()

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@@ -0,0 +1,4 @@
set(COMPONENT_SRCS "https_x509_bundle_example_main.c")
set(COMPONENT_ADD_INCLUDEDIRS ".")
register_component()

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@@ -0,0 +1,5 @@
#
# "main" pseudo-component makefile.
#
# (Uses default behaviour of compiling all source files in directory, adding 'include' to include path.)

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@@ -0,0 +1,97 @@
/* HTTPS GET Example using plain mbedTLS sockets
*
* Contacts the howsmyssl.com API via TLS v1.2 and reads a JSON
* response.
*
* Adapted from the ssl_client1 example in mbedtls.
*
* Original Copyright (C) 2006-2016, ARM Limited, All Rights Reserved, Apache 2.0 License.
* Additions Copyright (C) Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD, Apache 2.0 License.
*
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <string.h>
#include <stdlib.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_wifi.h"
#include "esp_event.h"
#include "esp_log.h"
#include "esp_system.h"
#include "nvs_flash.h"
#include "protocol_examples_common.h"
#include "esp_netif.h"
#include "lwip/err.h"
#include "lwip/sockets.h"
#include "lwip/sys.h"
#include "lwip/netdb.h"
#include "lwip/dns.h"
#include "esp_tls.h"
#include "esp_crt_bundle.h"
#define MAX_URLS 2
static const char *web_urls[MAX_URLS] = {
"https://www.howsmyssl.com/a/check",
"https://espressif.com",
};
static const char *TAG = "example";
static void https_get_task(void *pvParameters)
{
while (1) {
int conn_count = 0;
ESP_LOGI(TAG, "Connecting to %d URLs", MAX_URLS);
for (int i = 0; i < MAX_URLS; i++) {
esp_tls_cfg_t cfg = {
.crt_bundle_attach = esp_crt_bundle_attach,
};
struct esp_tls *tls = esp_tls_conn_http_new(web_urls[i], &cfg);
if (tls != NULL) {
ESP_LOGI(TAG, "Connection established to %s", web_urls[i]);
conn_count++;
} else {
ESP_LOGE(TAG, "Could not connect to %s", web_urls[i]);
}
esp_tls_conn_delete(tls);
vTaskDelay(1000 / portTICK_PERIOD_MS);
}
ESP_LOGI(TAG, "Completed %d connections", conn_count);
ESP_LOGI(TAG, "Starting over again...");
}
}
void app_main(void)
{
ESP_ERROR_CHECK( nvs_flash_init() );
esp_netif_init();
ESP_ERROR_CHECK(esp_event_loop_create_default());
/* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
* Read "Establishing Wi-Fi or Ethernet Connection" section in
* examples/protocols/README.md for more information about this function.
*/
ESP_ERROR_CHECK(example_connect());
xTaskCreate(&https_get_task, "https_get_task", 8192, NULL, 5, NULL);
}

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@@ -0,0 +1,5 @@
# CONFIG_MBEDTLS_CERTIFICATE_BUNDLE_DEFAULT_FULL is not set
# CONFIG_MBEDTLS_CERTIFICATE_BUNDLE_DEFAULT_CMN is not set
CONFIG_MBEDTLS_CERTIFICATE_BUNDLE_DEFAULT_NONE=y
CONFIG_MBEDTLS_CUSTOM_CERTIFICATE_BUNDLE=y
CONFIG_MBEDTLS_CUSTOM_CERTIFICATE_BUNDLE_PATH="certs"