/* * SPDX-FileCopyrightText: 2020-2021 Espressif Systems (Shanghai) CO LTD * * SPDX-License-Identifier: Apache-2.0 */ #include "utils/includes.h" #include "utils/common.h" #include "tls/tls.h" #include "crypto/sha1.h" #include "crypto/md5.h" #include "crypto/sha256.h" #include "crypto/sha384.h" #include "mbedtls/ssl_internal.h" #include "mbedtls/ctr_drbg.h" #include "mbedtls/entropy.h" #include "mbedtls/debug.h" #ifdef ESPRESSIF_USE #include "mbedtls/esp_debug.h" #include "mbedtls/esp_config.h" #else #include "mbedtls/config.h" #endif #define TLS_RANDOM_LEN 32 #define TLS_MASTER_SECRET_LEN 48 #define MAX_CIPHERSUITE 32 /* Throw a compilation error if basic requirements in mbedtls are not enabled */ #if !defined(MBEDTLS_SSL_TLS_C) #error "TLS not enabled in mbedtls config" #endif #if !defined(MBEDTLS_SHA256_C) #error "SHA256 is disabled in mbedtls config" #endif #if !defined(MBEDTLS_AES_C) #error "AES support is disabled in mbedtls config" #endif uint32_t tls_instance_count; struct tls_data { /* Data for mbedlts */ struct wpabuf *in_data; /* Data from mbedtls */ struct wpabuf *out_data; }; typedef struct tls_context { mbedtls_ssl_context ssl; /*!< TLS/SSL context */ mbedtls_entropy_context entropy; /*!< mbedTLS entropy context structure */ mbedtls_ctr_drbg_context ctr_drbg; /*!< mbedTLS ctr drbg context structure */ mbedtls_ssl_config conf; /*!< TLS/SSL config to be shared structures */ mbedtls_x509_crt cacert; /*!< Container for X.509 CA certificate */ mbedtls_x509_crt *cacert_ptr; /*!< Pointer to the cacert being used. */ mbedtls_x509_crt clientcert; /*!< Container for X.509 client certificate */ mbedtls_pk_context clientkey; /*!< Private key of client certificate */ int ciphersuite[MAX_CIPHERSUITE]; } tls_context_t; struct tls_connection { tls_context_t *tls; struct tls_data tls_io_data; unsigned char randbytes[2 * TLS_RANDOM_LEN]; }; static void tls_mbedtls_cleanup(tls_context_t *tls) { if (!tls) { return; } tls->cacert_ptr = NULL; mbedtls_x509_crt_free(&tls->cacert); mbedtls_x509_crt_free(&tls->clientcert); mbedtls_pk_free(&tls->clientkey); mbedtls_entropy_free(&tls->entropy); mbedtls_ssl_config_free(&tls->conf); mbedtls_ctr_drbg_free(&tls->ctr_drbg); mbedtls_ssl_free(&tls->ssl); } static void tls_mbedtls_conn_delete(tls_context_t *tls) { if (tls != NULL) { tls_mbedtls_cleanup(tls); } } static int tls_mbedtls_write(void *ctx, const unsigned char *buf, size_t len) { struct tls_connection *conn = (struct tls_connection *)ctx; struct tls_data *data = &conn->tls_io_data; if (data->out_data) { wpabuf_resize(&data->out_data, len); } else { data->out_data = wpabuf_alloc(len); } wpabuf_put_data(data->out_data, buf, len); return len; } static int tls_mbedtls_read(void *ctx, unsigned char *buf, size_t len) { struct tls_connection *conn = (struct tls_connection *)ctx; struct tls_data *data = &conn->tls_io_data; struct wpabuf *local_buf; size_t data_len = len; if (data->in_data == NULL) { return MBEDTLS_ERR_SSL_WANT_READ; } if (len > wpabuf_len(data->in_data)) { wpa_printf(MSG_ERROR, "don't have suffient data\n"); data_len = wpabuf_len(data->in_data); } os_memcpy(buf, wpabuf_head(data->in_data), data_len); /* adjust buffer */ if (len < wpabuf_len(data->in_data)) { local_buf = wpabuf_alloc_copy(wpabuf_head(data->in_data) + len, wpabuf_len(data->in_data) - len); wpabuf_free(data->in_data); data->in_data = local_buf; } else { wpabuf_free(data->in_data); data->in_data = NULL; } return data_len; } static int set_pki_context(tls_context_t *tls, const struct tls_connection_params *cfg) { int ret; if (cfg->client_cert_blob == NULL || cfg->private_key_blob == NULL) { wpa_printf(MSG_ERROR, "%s: config not correct", __func__); return -1; } mbedtls_x509_crt_init(&tls->clientcert); mbedtls_pk_init(&tls->clientkey); ret = mbedtls_x509_crt_parse(&tls->clientcert, cfg->client_cert_blob, cfg->client_cert_blob_len); if (ret < 0) { wpa_printf(MSG_ERROR, "mbedtls_x509_crt_parse returned -0x%x", -ret); return ret; } ret = mbedtls_pk_parse_key(&tls->clientkey, cfg->private_key_blob, cfg->private_key_blob_len, (const unsigned char *)cfg->private_key_passwd, cfg->private_key_passwd ? os_strlen(cfg->private_key_passwd) : 0); if (ret < 0) { wpa_printf(MSG_ERROR, "mbedtls_pk_parse_keyfile returned -0x%x", -ret); return ret; } ret = mbedtls_ssl_conf_own_cert(&tls->conf, &tls->clientcert, &tls->clientkey); if (ret < 0) { wpa_printf(MSG_ERROR, "mbedtls_ssl_conf_own_cert returned -0x%x", -ret); return ret; } return 0; } static int set_ca_cert(tls_context_t *tls, const unsigned char *cacert, size_t cacert_len) { tls->cacert_ptr = &tls->cacert; mbedtls_x509_crt_init(tls->cacert_ptr); int ret = mbedtls_x509_crt_parse(tls->cacert_ptr, cacert, cacert_len); if (ret < 0) { wpa_printf(MSG_ERROR, "mbedtls_x509_crt_parse returned -0x%x", -ret); return ret; } mbedtls_ssl_conf_authmode(&tls->conf, MBEDTLS_SSL_VERIFY_REQUIRED); mbedtls_ssl_conf_ca_chain(&tls->conf, tls->cacert_ptr, NULL); return 0; } #ifdef CONFIG_SUITEB192 static int tls_sig_hashes_for_suiteb[] = { #if defined(MBEDTLS_SHA512_C) MBEDTLS_MD_SHA512, MBEDTLS_MD_SHA384, #endif MBEDTLS_MD_NONE }; const mbedtls_x509_crt_profile suiteb_mbedtls_x509_crt_profile = { #if defined(MBEDTLS_SHA512_C) MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) | MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ) | #endif 0, 0xFFFFFFF, /* Any PK alg */ MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP384R1), 1024, }; static void tls_set_suiteb_config(tls_context_t *tls) { const mbedtls_x509_crt_profile *crt_profile = &suiteb_mbedtls_x509_crt_profile; mbedtls_ssl_conf_cert_profile(&tls->conf, crt_profile); mbedtls_ssl_conf_sig_hashes(&tls->conf, tls_sig_hashes_for_suiteb); } #endif static int tls_sig_hashes_for_eap[] = { #if defined(MBEDTLS_SHA512_C) MBEDTLS_MD_SHA512, MBEDTLS_MD_SHA384, #endif #if defined(MBEDTLS_SHA256_C) MBEDTLS_MD_SHA256, MBEDTLS_MD_SHA224, #endif #if defined(MBEDTLS_SHA1_C) MBEDTLS_MD_SHA1, #endif MBEDTLS_MD_NONE }; const mbedtls_x509_crt_profile eap_mbedtls_x509_crt_profile = { #if defined(MBEDTLS_SHA1_C) MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA1 ) | #endif #if defined(MBEDTLS_SHA256_C) MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA224 ) | MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) | #endif #if defined(MBEDTLS_SHA512_C) MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) | MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ) | #endif 0, 0xFFFFFFF, /* Any PK alg */ 0xFFFFFFF, /* Any curve */ 1024, }; static void tls_enable_sha1_config(tls_context_t *tls) { const mbedtls_x509_crt_profile *crt_profile = &eap_mbedtls_x509_crt_profile; mbedtls_ssl_conf_cert_profile(&tls->conf, crt_profile); mbedtls_ssl_conf_sig_hashes(&tls->conf, tls_sig_hashes_for_eap); } static const int eap_ciphersuite_preference[] = { #if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) #if defined(MBEDTLS_SHA512_C) && defined(MBEDTLS_GCM_C) MBEDTLS_TLS_DHE_RSA_WITH_AES_256_GCM_SHA384, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_DHE_RSA_WITH_AES_256_CCM, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_DHE_RSA_WITH_AES_256_CBC_SHA256, MBEDTLS_TLS_DHE_RSA_WITH_AES_256_CBC_SHA, #endif #if defined(MBEDTLS_GCM_C) MBEDTLS_TLS_DHE_RSA_WITH_CAMELLIA_256_GCM_SHA384, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256, MBEDTLS_TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA, #endif #if defined(MBEDTLS_GCM_C) MBEDTLS_TLS_DHE_RSA_WITH_AES_128_GCM_SHA256, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_DHE_RSA_WITH_AES_128_CCM, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_DHE_RSA_WITH_AES_128_CBC_SHA256, MBEDTLS_TLS_DHE_RSA_WITH_AES_128_CBC_SHA, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_DHE_RSA_WITH_AES_128_CCM_8, #endif #endif #if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) MBEDTLS_TLS_DHE_PSK_WITH_AES_256_GCM_SHA384, MBEDTLS_TLS_DHE_PSK_WITH_AES_256_CCM, MBEDTLS_TLS_DHE_PSK_WITH_AES_256_CBC_SHA384, MBEDTLS_TLS_DHE_PSK_WITH_AES_256_CBC_SHA, MBEDTLS_TLS_DHE_PSK_WITH_AES_256_CCM_8, MBEDTLS_TLS_DHE_PSK_WITH_AES_128_GCM_SHA256, MBEDTLS_TLS_DHE_PSK_WITH_AES_128_CCM, MBEDTLS_TLS_DHE_PSK_WITH_AES_128_CBC_SHA256, MBEDTLS_TLS_DHE_PSK_WITH_AES_128_CCM_8, #endif #if defined(MBEDTLS_SHA512_C) && defined(MBEDTLS_GCM_C) MBEDTLS_TLS_RSA_WITH_AES_256_GCM_SHA384, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_RSA_WITH_AES_256_CCM, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_RSA_WITH_AES_256_CBC_SHA256, MBEDTLS_TLS_RSA_WITH_AES_256_CBC_SHA, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_RSA_WITH_AES_256_CCM_8, #endif #if defined(MBEDTLS_GCM_C) MBEDTLS_TLS_RSA_WITH_AES_128_GCM_SHA256, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_RSA_WITH_AES_128_CCM, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_RSA_WITH_AES_128_CBC_SHA256, MBEDTLS_TLS_RSA_WITH_AES_128_CBC_SHA, #endif #if defined(MBEDTLS_GCM_C) MBEDTLS_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256, MBEDTLS_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA, #endif #if defined(MBEDTLS_GCM_C) MBEDTLS_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256, MBEDTLS_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_RSA_WITH_AES_128_CCM_8, #endif #if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) #if defined(MBEDTLS_GCM_C) MBEDTLS_TLS_RSA_PSK_WITH_AES_128_GCM_SHA256, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_RSA_PSK_WITH_AES_128_CBC_SHA256, MBEDTLS_TLS_RSA_PSK_WITH_AES_128_CBC_SHA, #endif /* The PSK suites */ #if defined(MBEDTLS_GCM_C) MBEDTLS_TLS_PSK_WITH_AES_256_GCM_SHA384, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_PSK_WITH_AES_256_CCM, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_PSK_WITH_AES_256_CBC_SHA384, MBEDTLS_TLS_PSK_WITH_AES_256_CBC_SHA, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_PSK_WITH_AES_256_CCM_8, #endif #if defined(MBEDTLS_GCM_C) MBEDTLS_TLS_PSK_WITH_AES_128_GCM_SHA256, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_PSK_WITH_AES_128_CCM, #endif #if defined(MBEDTLS_CIPHER_MODE_CBC) MBEDTLS_TLS_PSK_WITH_AES_128_CBC_SHA256, MBEDTLS_TLS_PSK_WITH_AES_128_CBC_SHA, #endif #if defined(MBEDTLS_CCM_C) MBEDTLS_TLS_PSK_WITH_AES_128_CCM_8, #endif #endif #if defined(MBEDTLS_DES_C) /* 3DES suites */ MBEDTLS_TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA, MBEDTLS_TLS_DHE_PSK_WITH_3DES_EDE_CBC_SHA, MBEDTLS_TLS_RSA_WITH_3DES_EDE_CBC_SHA, MBEDTLS_TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA, MBEDTLS_TLS_PSK_WITH_3DES_EDE_CBC_SHA, #endif #if defined(MBEDTLS_ARC4_C) /* RC4 suites */ MBEDTLS_TLS_DHE_PSK_WITH_RC4_128_SHA, MBEDTLS_TLS_RSA_WITH_RC4_128_SHA, MBEDTLS_TLS_RSA_WITH_RC4_128_MD5, MBEDTLS_TLS_RSA_PSK_WITH_RC4_128_SHA, MBEDTLS_TLS_PSK_WITH_RC4_128_SHA, #endif 0 }; #ifdef CONFIG_SUITEB192 static const int suiteb_rsa_ciphersuite_preference[] = { #if defined(MBEDTLS_GCM_C) #if defined(MBEDTLS_SHA512_C) MBEDTLS_TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, MBEDTLS_TLS_DHE_RSA_WITH_AES_256_GCM_SHA384, #endif #endif 0 }; static const int suiteb_ecc_ciphersuite_preference[] = { #if defined(MBEDTLS_GCM_C) #if defined(MBEDTLS_SHA512_C) MBEDTLS_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, #endif #endif 0 }; static const int suiteb_ciphersuite_preference[] = { #if defined(MBEDTLS_GCM_C) #if defined(MBEDTLS_SHA512_C) MBEDTLS_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, MBEDTLS_TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, MBEDTLS_TLS_DHE_RSA_WITH_AES_256_GCM_SHA384, #endif #endif 0 }; #endif static void tls_set_ciphersuite(const struct tls_connection_params *cfg, tls_context_t *tls) { /* Only set ciphersuite if cert's key length is high or ciphersuites are set by user */ #ifdef CONFIG_SUITEB192 if (cfg->flags & TLS_CONN_SUITEB) { /* cipher suites will be set based on certificate */ mbedtls_pk_type_t pk_alg = mbedtls_pk_get_type(&tls->clientkey); if (pk_alg == MBEDTLS_PK_RSA || pk_alg == MBEDTLS_PK_RSASSA_PSS) { mbedtls_ssl_conf_ciphersuites(&tls->conf, suiteb_rsa_ciphersuite_preference); } else if (pk_alg == MBEDTLS_PK_ECDSA || pk_alg == MBEDTLS_PK_ECKEY || pk_alg == MBEDTLS_PK_ECKEY_DH) { mbedtls_ssl_conf_ciphersuites(&tls->conf, suiteb_ecc_ciphersuite_preference); } else { mbedtls_ssl_conf_ciphersuites(&tls->conf, suiteb_ciphersuite_preference); } } else #endif if (tls->ciphersuite[0]) { mbedtls_ssl_conf_ciphersuites(&tls->conf, tls->ciphersuite); } else if (mbedtls_pk_get_bitlen(&tls->clientkey) > 2048 || (tls->cacert_ptr && mbedtls_pk_get_bitlen(&tls->cacert_ptr->pk) > 2048)) { mbedtls_ssl_conf_ciphersuites(&tls->conf, eap_ciphersuite_preference); } } static int set_client_config(const struct tls_connection_params *cfg, tls_context_t *tls) { int ret; int preset = MBEDTLS_SSL_PRESET_DEFAULT; assert(cfg != NULL); assert(tls != NULL); #ifdef CONFIG_SUITEB192 if (cfg->flags & TLS_CONN_SUITEB) preset = MBEDTLS_SSL_PRESET_SUITEB; #endif ret = mbedtls_ssl_config_defaults(&tls->conf, MBEDTLS_SSL_IS_CLIENT, MBEDTLS_SSL_TRANSPORT_STREAM, preset); if (ret != 0) { wpa_printf(MSG_ERROR, "mbedtls_ssl_config_defaults returned -0x%x", -ret); return ret; } if (preset != MBEDTLS_SSL_PRESET_SUITEB) { /* Enable SHA1 support since it's not enabled by default in mbedtls */ tls_enable_sha1_config(tls); #ifdef CONFIG_SUITEB192 } else { tls_set_suiteb_config(tls); #endif } if (cfg->ca_cert_blob != NULL) { ret = set_ca_cert(tls, cfg->ca_cert_blob, cfg->ca_cert_blob_len); if (ret != 0) { return ret; } mbedtls_ssl_conf_ca_chain(&tls->conf, tls->cacert_ptr, NULL); } else { mbedtls_ssl_conf_authmode(&tls->conf, MBEDTLS_SSL_VERIFY_NONE); } if (cfg->client_cert_blob != NULL && cfg->private_key_blob != NULL) { ret = set_pki_context(tls, cfg); if (ret != 0) { wpa_printf(MSG_ERROR, "Failed to set client pki context"); return ret; } } /* Usages of default ciphersuites can take a lot of time on low end device * and can cause watchdog. Enabling the ciphers which are secured enough * but doesn't take that much processing power */ tls_set_ciphersuite(cfg, tls); return 0; } static int tls_create_mbedtls_handle(const struct tls_connection_params *params, tls_context_t *tls) { int ret; assert(params != NULL); assert(tls != NULL); mbedtls_ssl_init(&tls->ssl); mbedtls_ctr_drbg_init(&tls->ctr_drbg); mbedtls_ssl_config_init(&tls->conf); mbedtls_entropy_init(&tls->entropy); ret = set_client_config(params, tls); if (ret != 0) { wpa_printf(MSG_ERROR, "Failed to set client configurations"); goto exit; } ret = mbedtls_ctr_drbg_seed(&tls->ctr_drbg, mbedtls_entropy_func, &tls->entropy, NULL, 0); if (ret != 0) { wpa_printf(MSG_ERROR, "mbedtls_ctr_drbg_seed returned -0x%x", -ret); goto exit; } mbedtls_ssl_conf_rng(&tls->conf, mbedtls_ctr_drbg_random, &tls->ctr_drbg); ret = mbedtls_ssl_setup(&tls->ssl, &tls->conf); if (ret != 0) { wpa_printf(MSG_ERROR, "mbedtls_ssl_setup returned -0x%x", -ret); goto exit; } #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING) /* Disable BEAST attack countermeasures for Windows 2008 interoperability */ mbedtls_ssl_conf_cbc_record_splitting(&tls->conf, MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED); #endif /* Enable debug prints in case supplicant's prints are enabled */ #if defined(DEBUG_PRINT) && defined(CONFIG_MBEDTLS_DEBUG) && defined(ESPRESSIF_USE) mbedtls_esp_enable_debug_log(&tls->conf, 2); #endif return 0; exit: tls_mbedtls_cleanup(tls); return ret; } void *tls_init() { tls_instance_count++; return &tls_instance_count; } void tls_deinit(void *tls_ctx) { tls_instance_count--; } struct tls_connection * tls_connection_init(void *tls_ctx) { struct tls_connection *conn = os_zalloc(sizeof(*conn)); if (!conn) { wpa_printf(MSG_ERROR, "TLS: Failed to allocate connection memory"); return NULL; } return conn; } void tls_connection_deinit(void *tls_ctx, struct tls_connection *conn) { /* case: tls init failed */ if (!conn) { return; } /* Free ssl ctx and data */ tls_mbedtls_conn_delete((tls_context_t *) conn->tls); os_free(conn->tls); conn->tls = NULL; /* Data in in ssl ctx, free connection */ os_free(conn); } int tls_get_errors(void *tls_ctx) { return 0; } int tls_connection_established(void *tls_ctx, struct tls_connection *conn) { mbedtls_ssl_context *ssl = &conn->tls->ssl; if (ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER) { return 1; } return 0; } int tls_global_set_verify(void *tls_ctx, int check_crl) { wpa_printf(MSG_INFO, "TLS: global settings are not supported"); return -1; } int tls_connection_set_verify(void *tls_ctx, struct tls_connection *conn, int verify_peer) { wpa_printf(MSG_INFO, "TLS: tls_connection_set_verify not supported"); return -1; } struct wpabuf * tls_connection_handshake(void *tls_ctx, struct tls_connection *conn, const struct wpabuf *in_data, struct wpabuf **appl_data) { tls_context_t *tls = conn->tls; int ret = 0; /* data freed by sender */ conn->tls_io_data.out_data = NULL; if (wpabuf_len(in_data)) { conn->tls_io_data.in_data = wpabuf_dup(in_data); } /* Multiple reads */ while (tls->ssl.state != MBEDTLS_SSL_HANDSHAKE_OVER) { if (tls->ssl.state == MBEDTLS_SSL_CLIENT_CERTIFICATE) { /* Read random data before session completes, not present after handshake */ if (tls->ssl.handshake) { os_memcpy(conn->randbytes, tls->ssl.handshake->randbytes, TLS_RANDOM_LEN * 2); } } ret = mbedtls_ssl_handshake_step(&tls->ssl); if (ret < 0) break; } if (ret < 0 && ret != MBEDTLS_ERR_SSL_WANT_READ) { wpa_printf(MSG_INFO, "%s: ret is %d line:%d", __func__, ret, __LINE__); goto end; } if (!conn->tls_io_data.out_data) { wpa_printf(MSG_INFO, "application data is null, adding one byte for ack"); u8 *dummy = os_zalloc(1); conn->tls_io_data.out_data = wpabuf_alloc_ext_data(dummy, 0); } end: return conn->tls_io_data.out_data; } struct wpabuf * tls_connection_server_handshake(void *tls_ctx, struct tls_connection *conn, const struct wpabuf *in_data, struct wpabuf **appl_data) { wpa_printf(MSG_ERROR, "%s: not supported %d", __func__, __LINE__); return NULL; } struct wpabuf * tls_connection_encrypt(void *tls_ctx, struct tls_connection *conn, const struct wpabuf *in_data) { /* Reset dangling pointer */ conn->tls_io_data.out_data = NULL; ssize_t ret = mbedtls_ssl_write(&conn->tls->ssl, (unsigned char*) wpabuf_head(in_data), wpabuf_len(in_data)); if (ret < wpabuf_len(in_data)) { wpa_printf(MSG_ERROR, "%s:%d, not able to write whole data", __func__, __LINE__); } return conn->tls_io_data.out_data; } struct wpabuf * tls_connection_decrypt(void *tls_ctx, struct tls_connection *conn, const struct wpabuf *in_data) { unsigned char buf[1200]; int ret; conn->tls_io_data.in_data = wpabuf_dup(in_data); ret = mbedtls_ssl_read(&conn->tls->ssl, buf, 1200); if (ret < 0) { wpa_printf(MSG_ERROR, "%s:%d, not able to write whole data", __func__, __LINE__); return NULL; } struct wpabuf *out = wpabuf_alloc_copy(buf, ret); return out; } int tls_connection_resumed(void *tls_ctx, struct tls_connection *conn) { if (conn && conn->tls && conn->tls->ssl.handshake) { return conn->tls->ssl.handshake->resume; } return 0; } /* cipher array should contain cipher number in mbedtls num as per IANA * Please see cipherlist is u8, therefore only initial ones are supported */ int tls_connection_set_cipher_list(void *tls_ctx, struct tls_connection *conn, u8 *ciphers) { int i = 0; while (*ciphers != 0 && i < MAX_CIPHERSUITE) { conn->tls->ciphersuite[i] = ciphers[i]; i++; } return 0; } int tls_get_version(void *tls_ctx, struct tls_connection *conn, char *buf, size_t buflen) { const char *name; if (conn == NULL) { return -1; } name = mbedtls_ssl_get_version(&conn->tls->ssl); if (name == NULL) { return -1; } os_strlcpy(buf, name, buflen); return 0; } int tls_get_cipher(void *tls_ctx, struct tls_connection *conn, char *buf, size_t buflen) { const char *name; if (conn == NULL) { return -1; } name = mbedtls_ssl_get_ciphersuite(&conn->tls->ssl); if (name == NULL) { return -1; } os_strlcpy(buf, name, buflen); return 0; } int tls_connection_enable_workaround(void *tls_ctx, struct tls_connection *conn) { wpa_printf(MSG_ERROR, "%s: not supported %d", __func__, __LINE__); return -1; } int tls_connection_get_failed(void *tls_ctx, struct tls_connection *conn) { return 0; } int tls_connection_get_read_alerts(void *tls_ctx, struct tls_connection *conn) { wpa_printf(MSG_ERROR, "%s: not supported %d", __func__, __LINE__); return 0; } int tls_connection_get_write_alerts(void *tls_ctx, struct tls_connection *conn) { wpa_printf(MSG_ERROR, "%s: not supported %d", __func__, __LINE__); return 0; } int tls_connection_set_params(void *tls_ctx, struct tls_connection *conn, const struct tls_connection_params *params) { int ret = 0; tls_context_t *tls = (tls_context_t *)os_zalloc(sizeof(tls_context_t)); if (!tls) { wpa_printf(MSG_ERROR, "failed to allocate tls context"); return -1; } if (!params) { wpa_printf(MSG_ERROR, "configuration is null"); ret = -1; goto err; } ret = tls_create_mbedtls_handle(params, tls); if (ret < 0) { wpa_printf(MSG_ERROR, "failed to create ssl handle"); goto err; } mbedtls_ssl_set_bio(&tls->ssl, conn, tls_mbedtls_write, tls_mbedtls_read, NULL); conn->tls = (tls_context_t *)tls; return ret; err: os_free(tls); return ret; } int tls_global_set_params(void *tls_ctx, const struct tls_connection_params *params) { wpa_printf(MSG_INFO, "TLS: Global parameters not supported"); return -1; } int tls_connection_set_session_ticket_cb(void *tls_ctx, struct tls_connection *conn, tls_session_ticket_cb cb, void *ctx) { wpa_printf(MSG_ERROR, "TLS: %s not supported", __func__); return -1; } static int tls_connection_prf(void *tls_ctx, struct tls_connection *conn, const char *label, int server_random_first, u8 *out, size_t out_len) { int ret; u8 seed[2 * TLS_RANDOM_LEN]; mbedtls_ssl_context *ssl = &conn->tls->ssl; mbedtls_ssl_transform *transform = ssl->transform; if (!ssl || !transform) { wpa_printf(MSG_ERROR, "TLS: %s, session ingo is null", __func__); return -1; } if (ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER) { wpa_printf(MSG_ERROR, "TLS: %s, incorrect tls state=%d", __func__, ssl->state); return -1; } if (server_random_first) { os_memcpy(seed, conn->randbytes + TLS_RANDOM_LEN, TLS_RANDOM_LEN); os_memcpy(seed + TLS_RANDOM_LEN, conn->randbytes, TLS_RANDOM_LEN); } else { os_memcpy(seed, conn->randbytes, 2 * TLS_RANDOM_LEN); } wpa_hexdump_key(MSG_MSGDUMP, "random", seed, 2 * TLS_RANDOM_LEN); wpa_hexdump_key(MSG_MSGDUMP, "master", ssl->session->master, TLS_MASTER_SECRET_LEN); if (transform->ciphersuite_info->mac == MBEDTLS_MD_SHA384) { ret = tls_prf_sha384(ssl->session->master, TLS_MASTER_SECRET_LEN, label, seed, 2 * TLS_RANDOM_LEN, out, out_len); } else if (transform->ciphersuite_info->mac == MBEDTLS_MD_SHA256) { ret = tls_prf_sha256(ssl->session->master, TLS_MASTER_SECRET_LEN, label, seed, 2 * TLS_RANDOM_LEN, out, out_len); } else { ret = tls_prf_sha1_md5(ssl->session->master, TLS_MASTER_SECRET_LEN, label, seed, 2 * TLS_RANDOM_LEN, out, out_len); } if (ret < 0) { wpa_printf(MSG_ERROR, "prf failed, ret=%d\n", ret); } wpa_hexdump_key(MSG_MSGDUMP, "key", out, out_len); return ret; } int tls_connection_export_key(void *tls_ctx, struct tls_connection *conn, const char *label, u8 *out, size_t out_len) { return tls_connection_prf(tls_ctx, conn, label, 0, out, out_len); } int tls_connection_shutdown(void *tls_ctx, struct tls_connection *conn) { if (conn->tls_io_data.in_data) { wpabuf_free(conn->tls_io_data.in_data); } conn->tls_io_data.in_data = NULL; /* outdata may have dangling pointer */ conn->tls_io_data.out_data = NULL; return mbedtls_ssl_session_reset(&conn->tls->ssl); } int tls_connection_get_random(void *tls_ctx, struct tls_connection *conn, struct tls_random *data) { mbedtls_ssl_context *ssl = &conn->tls->ssl; os_memset(data, 0, sizeof(*data)); if (ssl->state == MBEDTLS_SSL_CLIENT_HELLO) { return -1; } data->client_random = conn->randbytes; data->client_random_len = TLS_RANDOM_LEN; if (ssl->state != MBEDTLS_SSL_SERVER_HELLO) { data->server_random = conn->randbytes + TLS_RANDOM_LEN; data->server_random_len = TLS_RANDOM_LEN; } return 0; }