From 3e1a0c2091cb57814de96ce0974d91a4a47603f4 Mon Sep 17 00:00:00 2001 From: Stefan Schake Date: Fri, 11 Nov 2016 20:27:18 +0100 Subject: [PATCH] Start http_get example for BearSSL Validation fails due to invalid validation time (no time source on ESP) and wrong TA --- examples/http_get_bearssl/Makefile | 4 + examples/http_get_bearssl/http_get_bearssl.c | 267 +++++++++++++++++++ 2 files changed, 271 insertions(+) create mode 100644 examples/http_get_bearssl/Makefile create mode 100644 examples/http_get_bearssl/http_get_bearssl.c diff --git a/examples/http_get_bearssl/Makefile b/examples/http_get_bearssl/Makefile new file mode 100644 index 0000000..c16c561 --- /dev/null +++ b/examples/http_get_bearssl/Makefile @@ -0,0 +1,4 @@ +PROGRAM=http_get_bearssl +EXTRA_COMPONENTS = extras/bearssl + +include ../../common.mk diff --git a/examples/http_get_bearssl/http_get_bearssl.c b/examples/http_get_bearssl/http_get_bearssl.c new file mode 100644 index 0000000..8de22a3 --- /dev/null +++ b/examples/http_get_bearssl/http_get_bearssl.c @@ -0,0 +1,267 @@ +/* http_get_mbedtls - HTTPS version of the http_get example, using mbed TLS. + * + * Retrieves a JSON response from the howsmyssl.com API via HTTPS over TLS v1.2. + * + * Validates the server's certificate using the root CA loaded (in PEM format) in cert.c. + * + * Adapted from the ssl_client1 example in mbedtls. + * + * Original Copyright (C) 2006-2015, ARM Limited, All Rights Reserved, Apache 2.0 License. + * Additions Copyright (C) 2015 Angus Gratton, Apache 2.0 License. + */ +#include "espressif/esp_common.h" +#include "esp/uart.h" +#include "esp/hwrand.h" + +#include + +#include "FreeRTOS.h" +#include "task.h" + +#include "lwip/err.h" +#include "lwip/sockets.h" +#include "lwip/sys.h" +#include "lwip/netdb.h" +#include "lwip/dns.h" +#include "lwip/api.h" + +#include "ssid_config.h" + +#include "bearssl.h" + +#define WEB_SERVER "www.howsmyssl.com" +#define WEB_PORT "443" +#define WEB_URL "https://www.howsmyssl.com/a/check" + +#define GET_REQUEST "GET "WEB_URL" HTTP/1.1\nHost: "WEB_SERVER"\n\n" + +static const unsigned char TA0_DN[] = { + 0x30, 0x1C, 0x31, 0x0B, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x06, 0x13, + 0x02, 0x43, 0x41, 0x31, 0x0D, 0x30, 0x0B, 0x06, 0x03, 0x55, 0x04, 0x03, + 0x13, 0x04, 0x52, 0x6F, 0x6F, 0x74 +}; + +static const unsigned char TA0_RSA_N[] = { + 0xB6, 0xD9, 0x34, 0xD4, 0x50, 0xFD, 0xB3, 0xAF, 0x7A, 0x73, 0xF1, 0xCE, + 0x38, 0xBF, 0x5D, 0x6F, 0x45, 0xE1, 0xFD, 0x4E, 0xB1, 0x98, 0xC6, 0x60, + 0x83, 0x26, 0xD2, 0x17, 0xD1, 0xC5, 0xB7, 0x9A, 0xA3, 0xC1, 0xDE, 0x63, + 0x39, 0x97, 0x9C, 0xF0, 0x5E, 0x5C, 0xC8, 0x1C, 0x17, 0xB9, 0x88, 0x19, + 0x6D, 0xF0, 0xB6, 0x2E, 0x30, 0x50, 0xA1, 0x54, 0x6E, 0x93, 0xC0, 0xDB, + 0xCF, 0x30, 0xCB, 0x9F, 0x1E, 0x27, 0x79, 0xF1, 0xC3, 0x99, 0x52, 0x35, + 0xAA, 0x3D, 0xB6, 0xDF, 0xB0, 0xAD, 0x7C, 0xCB, 0x49, 0xCD, 0xC0, 0xED, + 0xE7, 0x66, 0x10, 0x2A, 0xE9, 0xCE, 0x28, 0x1F, 0x21, 0x50, 0xFA, 0x77, + 0x4C, 0x2D, 0xDA, 0xEF, 0x3C, 0x58, 0xEB, 0x4E, 0xBF, 0xCE, 0xE9, 0xFB, + 0x1A, 0xDA, 0xA3, 0x83, 0xA3, 0xCD, 0xA3, 0xCA, 0x93, 0x80, 0xDC, 0xDA, + 0xF3, 0x17, 0xCC, 0x7A, 0xAB, 0x33, 0x80, 0x9C, 0xB2, 0xD4, 0x7F, 0x46, + 0x3F, 0xC5, 0x3C, 0xDC, 0x61, 0x94, 0xB7, 0x27, 0x29, 0x6E, 0x2A, 0xBC, + 0x5B, 0x09, 0x36, 0xD4, 0xC6, 0x3B, 0x0D, 0xEB, 0xBE, 0xCE, 0xDB, 0x1D, + 0x1C, 0xBC, 0x10, 0x6A, 0x71, 0x71, 0xB3, 0xF2, 0xCA, 0x28, 0x9A, 0x77, + 0xF2, 0x8A, 0xEC, 0x42, 0xEF, 0xB1, 0x4A, 0x8E, 0xE2, 0xF2, 0x1A, 0x32, + 0x2A, 0xCD, 0xC0, 0xA6, 0x46, 0x2C, 0x9A, 0xC2, 0x85, 0x37, 0x91, 0x7F, + 0x46, 0xA1, 0x93, 0x81, 0xA1, 0x74, 0x66, 0xDF, 0xBA, 0xB3, 0x39, 0x20, + 0x91, 0x93, 0xFA, 0x1D, 0xA1, 0xA8, 0x85, 0xE7, 0xE4, 0xF9, 0x07, 0xF6, + 0x10, 0xF6, 0xA8, 0x27, 0x01, 0xB6, 0x7F, 0x12, 0xC3, 0x40, 0xC3, 0xC9, + 0xE2, 0xB0, 0xAB, 0x49, 0x18, 0x3A, 0x64, 0xB6, 0x59, 0xB7, 0x95, 0xB5, + 0x96, 0x36, 0xDF, 0x22, 0x69, 0xAA, 0x72, 0x6A, 0x54, 0x4E, 0x27, 0x29, + 0xA3, 0x0E, 0x97, 0x15 +}; + +static const unsigned char TA0_RSA_E[] = { + 0x01, 0x00, 0x01 +}; + +static const unsigned char TA1_DN[] = { + 0x30, 0x1C, 0x31, 0x0B, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x06, 0x13, + 0x02, 0x43, 0x41, 0x31, 0x0D, 0x30, 0x0B, 0x06, 0x03, 0x55, 0x04, 0x03, + 0x13, 0x04, 0x52, 0x6F, 0x6F, 0x74 +}; + +static const unsigned char TA1_EC_Q[] = { + 0x04, 0x71, 0x74, 0xBA, 0xAB, 0xB9, 0x30, 0x2E, 0x81, 0xD5, 0xE5, 0x57, + 0xF9, 0xF3, 0x20, 0x68, 0x0C, 0x9C, 0xF9, 0x64, 0xDB, 0xB4, 0x20, 0x0D, + 0x6D, 0xEA, 0x40, 0xD0, 0x4A, 0x6E, 0x42, 0xFD, 0xB6, 0x9A, 0x68, 0x25, + 0x44, 0xF6, 0xDF, 0x7B, 0xC4, 0xFC, 0xDE, 0xDD, 0x7B, 0xBB, 0xC5, 0xDB, + 0x7C, 0x76, 0x3F, 0x41, 0x66, 0x40, 0x6E, 0xDB, 0xA7, 0x87, 0xC2, 0xE5, + 0xD8, 0xC5, 0xF3, 0x7F, 0x8D +}; + +static const br_x509_trust_anchor TAs[2] = { + { + (unsigned char *)TA0_DN, sizeof TA0_DN, + BR_X509_TA_CA, + { + BR_KEYTYPE_RSA, + { .rsa = { + (unsigned char *)TA0_RSA_N, sizeof TA0_RSA_N, + (unsigned char *)TA0_RSA_E, sizeof TA0_RSA_E, + } } + } + }, + { + (unsigned char *)TA1_DN, sizeof TA1_DN, + BR_X509_TA_CA, + { + BR_KEYTYPE_EC, + { .ec = { + BR_EC_secp256r1, + (unsigned char *)TA1_EC_Q, sizeof TA1_EC_Q, + } } + } + } +}; + +#define TAs_NUM 2 + +/* + * Low-level data read callback for the simplified SSL I/O API. + */ +static int +sock_read(void *ctx, unsigned char *buf, size_t len) +{ + for (;;) { + ssize_t rlen; + + rlen = read(*(int *)ctx, buf, len); + if (rlen <= 0) { + if (rlen < 0 && errno == EINTR) { + continue; + } + return -1; + } + return (int)rlen; + } +} + +/* + * Low-level data write callback for the simplified SSL I/O API. + */ +static int +sock_write(void *ctx, const unsigned char *buf, size_t len) +{ + for (;;) { + ssize_t wlen; + + wlen = write(*(int *)ctx, buf, len); + if (wlen <= 0) { + if (wlen < 0 && errno == EINTR) { + continue; + } + return -1; + } + return (int)wlen; + } +} + +// In mono mode, BearSSL requires ~16k of buffer +// TODO: investigate Maximum Fragment Length (RFC 6066) extension +static unsigned char bearssl_buffer[BR_SSL_BUFSIZE_MONO]; +static br_ssl_client_context sc; +static br_x509_minimal_context xc; +static br_sslio_context ioc; + +void http_get_task(void *pvParameters) +{ + int successes = 0, failures = 0; + while (1) { + /* Wait until we can resolve the DNS for the server, as an indication + our network is probably working... + */ + const struct addrinfo hints = { + .ai_family = AF_INET, + .ai_socktype = SOCK_STREAM, + }; + struct addrinfo *res = NULL; + int dns_err = 0; + do { + if (res) + freeaddrinfo(res); + vTaskDelay(1000 / portTICK_PERIOD_MS); + dns_err = getaddrinfo(WEB_SERVER, WEB_PORT, &hints, &res); + } while(dns_err != 0 || res == NULL); + + int fd = socket(res->ai_family, res->ai_socktype, 0); + if (fd < 0) { + freeaddrinfo(res); + printf("socket failed\n"); + failures++; + continue; + } + + printf("Initializing BearSSL... "); + br_ssl_client_init_full(&sc, &xc, TAs, TAs_NUM); + br_ssl_engine_set_buffer(&sc.eng, bearssl_buffer, sizeof bearssl_buffer, 0); + // Inject some entropy from the ESP hardware RNG + // This is necessary because we don't support any of the BearSSL methods + for (int i = 0; i < 10; i++) { + int rand = hwrand(); + br_ssl_engine_inject_entropy(&sc.eng, &rand, 4); + } + br_ssl_client_reset(&sc, WEB_SERVER, 0); + br_sslio_init(&ioc, &sc.eng, sock_read, &fd, sock_write, &fd); + printf("done.\r\n"); + + if (connect(fd, res->ai_addr, res->ai_addrlen) != 0) + { + close(fd); + freeaddrinfo(res); + printf("connect failed\n"); + failures++; + continue; + } + printf("Connected\r\n"); + + if (br_sslio_write_all(&ioc, GET_REQUEST, strlen(GET_REQUEST)) != BR_ERR_OK) + { + close(fd); + freeaddrinfo(res); + printf("br_sslio_write_all failed: %d\r\n", br_ssl_engine_last_error(&sc.eng)); + failures++; + continue; + } + br_sslio_flush(&ioc); + + for (;;) + { + int rlen; + unsigned char buf[128]; + + bzero(buf, 128); + // Leave the final byte for zero termination + rlen = br_sslio_read(&ioc, buf, sizeof(buf) - 1); + + if (rlen < 0) { + break; + } + if (rlen > 0) { + printf("%s", buf); + } + } + + close(fd); + freeaddrinfo(res); + successes++; + printf("successes = %d failures = %d\r\n", successes, failures); + for(int countdown = 10; countdown >= 0; countdown--) { + printf("%d... ", countdown); + vTaskDelay(1000 / portTICK_PERIOD_MS); + } + printf("\r\nStarting again!\r\n"); + } +} + +void user_init(void) +{ + uart_set_baud(0, 115200); + printf("SDK version:%s\n", sdk_system_get_sdk_version()); + + struct sdk_station_config config = { + .ssid = WIFI_SSID, + .password = WIFI_PASS, + }; + + /* required to call wifi_set_opmode before station_set_config */ + sdk_wifi_set_opmode(STATION_MODE); + sdk_wifi_station_set_config(&config); + + xTaskCreate(&http_get_task, "get_task", 2048, NULL, 2, NULL); +}