OVMS3-idf/components/coap/port/coap_mbedtls.c
Jon Shallow 1aaec808da Add DTLS support to libcoap using MbedTLS
This update supports DTLS, TLS is a future TODO

components/coap/CMakeLists.txt:
components/coap/component.mk:

Add in the new files that have to be built
Replace libcoap/src/coap_notls.c with libcoap/src/coap_mbedtls.c

components/coap/libcoap:

Update the version to include the current version for supporting MbedTLS

components/coap/port/coap_debug.c:
components/coap/port/coap_mbedtls.c:
components/coap/port/include/coap/coap_dtls.h:

New port files for DTLS

components/coap/port/include/coap_config_posix.h:

Include building with MbedTLS

examples/protocols/coap_client/README.md:
examples/protocols/coap_client/main/CMakeLists.txt:
examples/protocols/coap_client/main/Kconfig.projbuild:
examples/protocols/coap_client/main/coap_client_example_main.c:
examples/protocols/coap_client/main/component.mk:

Update CoAP client to support DTLS

examples/protocols/coap_client/main/coap_ca.pem
examples/protocols/coap_client/main/coap_client.crt
examples/protocols/coap_client/main/coap_client.key

New PKI Certs for CoAP client (copied from wpa2_enterprise example)

examples/protocols/coap_server/README.md:
examples/protocols/coap_server/main/CMakeLists.txt:
examples/protocols/coap_server/main/Kconfig.projbuild:
examples/protocols/coap_server/main/coap_server_example_main.c:
examples/protocols/coap_server/main/component.mk:

Update CoAP server to support DTLS
Change "no data" to "Hello World!" to prevent confusion

examples/protocols/coap_server/main/coap_ca.pem
examples/protocols/coap_server/main/coap_server.crt
examples/protocols/coap_server/main/coap_server.key

New PKI Certs for CoAP server (copied from wpa2_enterprise example)

Closes https://github.com/espressif/esp-idf/pull/3345
Closes https://github.com/espressif/esp-idf/issues/1379
2019-08-06 10:37:40 +05:30

1796 lines
52 KiB
C

/*
* coap_mbedtls.c -- mbedTLS Datagram Transport Layer Support for libcoap
*
* Copyright (C) 2019 Jon Shallow <supjps-libcoap@jpshallow.com>
* 2019 Jitin George <jitin@espressif.com>
*
* This file is part of the CoAP library libcoap. Please see README for terms
* of use.
*/
/*
* Naming used to prevent confusion between coap sessions, mbedtls sessions etc.
* when reading the code.
*
* c_context A coap_context_t *
* c_session A coap_session_t *
* m_context A coap_mbedtls_context_t * (held in c_context->dtls_context)
* m_env A coap_mbedtls_env_t * (held in c_session->tls)
*/
#include "coap_config.h"
#ifdef HAVE_MBEDTLS
/*
* Once PS #335 has been merged in, then code following a rebase needs to be
* updated removing sections that are "#ifndef PSK2_PR", and then remove all
* references to PSK2_PR.
*/
#undef PSK2_PR
#include "libcoap.h"
#include "coap_dtls.h"
#include "net.h"
#include "mem.h"
#include "coap_debug.h"
#include "prng.h"
#include "coap_mutex.h"
#include <mbedtls/version.h>
#include <mbedtls/platform.h>
#include <mbedtls/net_sockets.h>
#include <mbedtls/ssl.h>
#include <mbedtls/entropy.h>
#include <mbedtls/ctr_drbg.h>
#include <mbedtls/error.h>
#include <mbedtls/certs.h>
#include <mbedtls/timing.h>
#include <mbedtls/ssl_cookie.h>
#include <mbedtls/debug.h>
#if defined(ESPIDF_VERSION) && defined(CONFIG_MBEDTLS_DEBUG)
#include <mbedtls/esp_debug.h>
#endif /* ESPIDF_VERSION && CONFIG_MBEDTLS_DEBUG */
#include <errno.h>
#include <arpa/inet.h>
#define mbedtls_malloc(a) malloc(a)
#define mbedtls_realloc(a,b) realloc(a,b)
#define mbedtls_strdup(a) strdup(a)
#ifdef __GNUC__
#define UNUSED __attribute__((unused))
#else /* __GNUC__ */
#define UNUSED
#endif /* __GNUC__ */
#define IS_PSK (1 << 0)
#define IS_PKI (1 << 1)
#define IS_CLIENT (1 << 6)
#define IS_SERVER (1 << 7)
typedef struct coap_ssl_t {
const uint8_t *pdu;
unsigned pdu_len;
unsigned peekmode;
coap_tick_t timeout;
} coap_ssl_t;
/*
* This structure encapsulates the mbedTLS session object.
* It handles both TLS and DTLS.
* c_session->tls points to this.
*/
typedef struct coap_mbedtls_env_t {
mbedtls_ssl_context ssl;
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_ssl_config conf;
mbedtls_timing_delay_context timer;
mbedtls_x509_crt cacert;
mbedtls_x509_crt public_cert;
mbedtls_pk_context private_key;
mbedtls_ssl_cookie_ctx cookie_ctx;
/* If not set, need to do do_mbedtls_handshake */
int established;
int seen_client_hello;
coap_ssl_t coap_ssl_data;
} coap_mbedtls_env_t;
typedef struct pki_sni_entry {
char *sni;
coap_dtls_key_t pki_key;
mbedtls_x509_crt cacert;
mbedtls_x509_crt public_cert;
mbedtls_pk_context private_key;
} pki_sni_entry;
#ifdef PSK2_PR
typedef struct psk_sni_entry {
coap_string_t sni;
coap_dtls_spsk_info_t psk_info;
} psk_sni_entry;
#endif /* PSK2_PR */
typedef struct coap_mbedtls_context_t {
coap_dtls_pki_t setup_data;
size_t pki_sni_count;
pki_sni_entry *pki_sni_entry_list;
#ifdef PSK2_PR
size_t psk_sni_count;
psk_sni_entry *psk_sni_entry_list;
#endif /* PSK2_PR */
char *root_ca_file;
char *root_ca_path;
int psk_pki_enabled;
} coap_mbedtls_context_t;
static int coap_dgram_read(void *ctx, unsigned char *out, size_t outl)
{
ssize_t ret = 0;
coap_session_t *c_session = (struct coap_session_t *)ctx;
coap_ssl_t *data = &((coap_mbedtls_env_t *)c_session->tls)->coap_ssl_data;
if (!c_session->tls) {
errno = EAGAIN;
return MBEDTLS_ERR_SSL_WANT_READ;
}
if (out != NULL) {
if (data != NULL && data->pdu_len > 0) {
if (outl < data->pdu_len) {
memcpy(out, data->pdu, outl);
ret = outl;
data->pdu += outl;
data->pdu_len -= outl;
}
else {
memcpy(out, data->pdu, data->pdu_len);
ret = data->pdu_len;
if (!data->peekmode) {
data->pdu_len = 0;
data->pdu = NULL;
}
}
}
else {
ret = MBEDTLS_ERR_SSL_WANT_READ;
errno = EAGAIN;
return ret;
}
}
return ret;
}
/*
* return +ve data amount
* 0 no more
* -1 error (error in errno)
*/
/* callback function given to mbedtls for sending data over socket */
static int
coap_dgram_write(void *ctx, const unsigned char *send_buffer,
size_t send_buffer_length)
{
ssize_t result = -1;
coap_session_t *c_session = (struct coap_session_t *)ctx;
if (c_session) {
result = coap_session_send(c_session, send_buffer, send_buffer_length);
if (result != (int)send_buffer_length) {
coap_log(LOG_WARNING, "coap_network_send failed (%zd != %zd)\n",
result, send_buffer_length);
result = 0;
}
} else {
result = 0;
}
return result;
}
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS)
static char*
get_ip_addr(const struct coap_address_t *addr)
{
const void *addrptr = NULL;
size_t buf_len;
if (!addr) {
return NULL;
}
switch (addr->addr.sa.sa_family) {
case AF_INET:
addrptr = &addr->addr.sin.sin_addr;
buf_len = INET_ADDRSTRLEN;
break;
case AF_INET6:
addrptr = &addr->addr.sin6.sin6_addr;
buf_len = INET6_ADDRSTRLEN;
break;
default:
return NULL;
}
char *str = (char *)mbedtls_calloc(1, buf_len);
if (!str) {
coap_log(LOG_ERR, "Memory allocation failed\n");
return NULL;
}
if (inet_ntop(addr->addr.sa.sa_family, addrptr, str,
buf_len) == 0) {
perror("coap_print_addr");
return 0;
}
return str;
}
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
#if !defined(ESPIDF_VERSION) || (defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS) && defined(CONFIG_MBEDTLS_PSK_MODES))
/*
* Server side PSK callback
*/
static int psk_server_callback(void *p_info, mbedtls_ssl_context *ssl,
const unsigned char *name, size_t name_len )
{
coap_session_t *c_session =
(coap_session_t *)p_info;
uint8_t buf[128];
size_t psk_len;
#ifdef PSK2_PR
coap_dtls_spsk_t *setup_data;
#endif /* PSK2_PR */
coap_mbedtls_env_t *m_env;
coap_log(LOG_DEBUG, "got psk_identity: '%.*s'\n",
(int)name_len, name);
if (c_session == NULL || c_session->context == NULL ||
c_session->context->get_server_psk == NULL) {
return -1;
}
m_env = (coap_mbedtls_env_t *)c_session->tls;
#ifdef PSK2_PR
setup_data = &c_session->context->spsk_setup_data;
if (setup_data->validate_id_call_back) {
coap_bin_const_t lidentity;
lidentity.length = name_len;
lidentity.s = (const uint8_t*)name;
const coap_bin_const_t *psk_key =
setup_data->validate_id_call_back(&lidentity,
c_session,
setup_data->id_call_back_arg);
if (psk_key == NULL)
return -1;
mbedtls_ssl_set_hs_psk(ssl, psk_key->s, psk_key->length);
coap_session_refresh_psk_key(c_session, psk_key);
m_env->seen_client_hello = 1;
return 0;
}
#endif /* PSK2_PR */
psk_len = c_session->context->get_server_psk(c_session,
(const uint8_t*)name,
name_len,
(uint8_t*)buf, sizeof(buf));
m_env->seen_client_hello = 1;
mbedtls_ssl_set_hs_psk(ssl, buf, psk_len);
return 0;
}
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
static char*
get_san_or_cn_from_cert(mbedtls_x509_crt *crt)
{
if (crt) {
#if COAP_CONSTRAINED_STACK
static coap_mutex_t a_static_mutex = COAP_MUTEX_INITIALIZER;
static char buf[1024];
#else /* ! COAP_CONSTRAINED_STACK */
char buf[1024];
#endif /* ! COAP_CONSTRAINED_STACK */
char *cn;
char *cp;
char *tcp;
int n;
#if COAP_CONSTRAINED_STACK
coap_mutex_lock(&a_static_mutex);
#endif /* COAP_CONSTRAINED_STACK */
mbedtls_x509_crt_info(buf, sizeof(buf) - 1, "", crt );
/* Look first to see if Subject Alt Name is defined */
cp = strstr(buf, "subject alt name");
if (cp) {
cp = strchr(cp, ':');
if (cp) {
cp++;
while (*cp == ' ') cp++;
tcp = strchr(cp, '\n');
if (tcp)
*tcp = '\000';
/* Take only the first entry */
tcp = strchr(cp, ',');
if (tcp)
*tcp = '\000';
/* Return the Subject Alt Name */
#if COAP_CONSTRAINED_STACK
coap_mutex_unlock(&a_static_mutex);
#endif /* COAP_CONSTRAINED_STACK */
return mbedtls_strdup(cp);
}
}
/* Pull CN= out of subject name */
cp = strstr(buf, "subject name");
if (cp) {
cp = strchr(cp, ':');
if (cp) {
cp++;
while (*cp == ' ') cp++;
tcp = strchr(cp, '\n');
if (tcp)
*tcp = '\000';
/* Need to emulate strcasestr() here. Looking for CN= */
n = strlen(cp) - 3;
cn = cp;
while (n > 0) {
if (((cn[0] == 'C') || (cn[0] == 'c')) &&
((cn[1] == 'N') || (cn[1] == 'n')) &&
(cn[2] == '=')) {
cn += 3;
break;
}
cn++;
n--;
}
if (n > 0) {
tcp = strchr(cn, ',');
if (tcp)
*tcp = '\000';
#if COAP_CONSTRAINED_STACK
coap_mutex_unlock(&a_static_mutex);
#endif /* COAP_CONSTRAINED_STACK */
return mbedtls_strdup(cn);
}
}
}
#if COAP_CONSTRAINED_STACK
coap_mutex_unlock(&a_static_mutex);
#endif /* COAP_CONSTRAINED_STACK */
}
return NULL;
}
/*
* return 0 All OK
* -ve Error Code
*/
static int
cert_verify_callback_mbedtls(void *data, mbedtls_x509_crt *crt,
int depth, uint32_t *flags)
{
coap_session_t *c_session = (coap_session_t*)data;
coap_mbedtls_context_t *m_context =
(coap_mbedtls_context_t *)c_session->context->dtls_context;
coap_dtls_pki_t *setup_data = &m_context->setup_data;
char *cn = NULL;
if (*flags == 0)
return 0;
if (!setup_data->verify_peer_cert) {
/* Nothing is being checked */
*flags = 0;
return 0;
}
cn = get_san_or_cn_from_cert(crt);
if (*flags & MBEDTLS_X509_BADCERT_EXPIRED) {
if (setup_data->allow_expired_certs) {
*flags &= ~MBEDTLS_X509_BADCERT_EXPIRED;
coap_log(LOG_WARNING,
" %s: %s: overridden: '%s' depth %d\n",
coap_session_str(c_session),
"The certificate has expired", cn ? cn : "?", depth);
}
}
if (*flags & MBEDTLS_X509_BADCERT_FUTURE) {
if (setup_data->allow_expired_certs) {
*flags &= ~MBEDTLS_X509_BADCERT_FUTURE;
coap_log(LOG_WARNING,
" %s: %s: overridden: '%s' depth %d\n",
coap_session_str(c_session),
"The certificate has a future date", cn ? cn : "?", depth);
}
}
if (*flags & MBEDTLS_X509_BADCERT_BAD_MD) {
if (setup_data->allow_bad_md_hash) {
*flags &= ~MBEDTLS_X509_BADCERT_BAD_MD;
coap_log(LOG_WARNING,
" %s: %s: overridden: '%s' depth %d\n",
coap_session_str(c_session),
"The certificate has a bad MD hash", cn ? cn : "?", depth);
}
}
if (*flags & MBEDTLS_X509_BADCERT_BAD_KEY) {
if (setup_data->allow_short_rsa_length) {
*flags &= ~MBEDTLS_X509_BADCERT_BAD_KEY;
coap_log(LOG_WARNING,
" %s: %s: overridden: '%s' depth %d\n",
coap_session_str(c_session),
"The certificate has a short RSA length", cn ? cn : "?", depth);
}
}
if (*flags & MBEDTLS_X509_BADCRL_EXPIRED) {
if (setup_data->check_cert_revocation && setup_data->allow_expired_crl) {
*flags &= ~MBEDTLS_X509_BADCRL_EXPIRED;
coap_log(LOG_WARNING,
" %s: %s: overridden: '%s' depth %d\n",
coap_session_str(c_session),
"The certificate's CRL has expired", cn ? cn : "?", depth);
}
else if (!setup_data->check_cert_revocation) {
*flags &= ~MBEDTLS_X509_BADCRL_EXPIRED;
}
}
if (*flags & MBEDTLS_X509_BADCRL_FUTURE) {
if (setup_data->check_cert_revocation && setup_data->allow_expired_crl) {
*flags &= ~MBEDTLS_X509_BADCRL_FUTURE;
coap_log(LOG_WARNING,
" %s: %s: overridden: '%s' depth %d\n",
coap_session_str(c_session),
"The certificate's CRL has a future date", cn ? cn : "?", depth);
}
else if (!setup_data->check_cert_revocation) {
*flags &= ~MBEDTLS_X509_BADCRL_FUTURE;
}
}
if (*flags & MBEDTLS_X509_BADCERT_CN_MISMATCH) {
*flags &= ~MBEDTLS_X509_BADCERT_CN_MISMATCH;
}
if (setup_data->validate_cn_call_back) {
if (!setup_data->validate_cn_call_back(cn,
crt->raw.p,
crt->raw.len,
c_session,
depth,
*flags == 0,
setup_data->cn_call_back_arg)) {
*flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
}
}
if (*flags != 0) {
char buf[128];
char *tcp;
mbedtls_x509_crt_verify_info(buf, sizeof(buf), "", *flags);
tcp = strchr(buf, '\n');
while (tcp) {
*tcp = '\000';
coap_log(LOG_WARNING,
" %s: %s: issue 0x%x: '%s' depth %d\n",
coap_session_str(c_session),
buf, *flags, cn ? cn : "?", depth);
tcp = strchr(tcp+1, '\n');
}
}
if (cn)
mbedtls_free(cn);
return 0;
}
static int
setup_pki_credentials(mbedtls_x509_crt *cacert,
mbedtls_x509_crt *public_cert,
mbedtls_pk_context *private_key,
coap_mbedtls_env_t *m_env,
coap_mbedtls_context_t *m_context,
coap_session_t *c_session,
coap_dtls_pki_t *setup_data,
coap_dtls_role_t role)
{
int ret;
switch (setup_data->pki_key.key_type) {
case COAP_PKI_KEY_PEM:
if (setup_data->pki_key.key.pem.public_cert &&
setup_data->pki_key.key.pem.public_cert[0] &&
setup_data->pki_key.key.pem.private_key &&
setup_data->pki_key.key.pem.private_key[0]) {
mbedtls_x509_crt_init(public_cert);
mbedtls_pk_init(private_key);
ret = mbedtls_x509_crt_parse_file(public_cert,
setup_data->pki_key.key.pem.public_cert);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_x509_crt_parse_file returned -0x%x\n\n",
-ret);
return ret;
}
ret = mbedtls_pk_parse_keyfile(private_key,
setup_data->pki_key.key.pem.private_key, NULL);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_pk_parse_keyfile returned -0x%x\n\n", -ret);
return ret;
}
ret = mbedtls_ssl_conf_own_cert(&m_env->conf, public_cert, private_key);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_ssl_conf_own_cert returned -0x%x\n\n", -ret);
return ret;
}
}
else if (role == COAP_DTLS_ROLE_SERVER) {
coap_log(LOG_ERR,
"***setup_pki: (D)TLS: No %s Certificate + Private "
"Key defined\n",
role == COAP_DTLS_ROLE_SERVER ? "Server" : "Client");
return -1;
}
if (setup_data->pki_key.key.pem.ca_file &&
setup_data->pki_key.key.pem.ca_file[0]) {
mbedtls_x509_crt_init(cacert);
ret = mbedtls_x509_crt_parse_file(cacert,
setup_data->pki_key.key.pem.ca_file);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_x509_crt_parse returned -0x%x\n\n", -ret);
return ret;
}
mbedtls_ssl_conf_authmode(&m_env->conf, setup_data->require_peer_cert ?
MBEDTLS_SSL_VERIFY_REQUIRED :
MBEDTLS_SSL_VERIFY_OPTIONAL);
mbedtls_ssl_conf_ca_chain(&m_env->conf, cacert, NULL);
}
break;
case COAP_PKI_KEY_PEM_BUF:
if (setup_data->pki_key.key.pem_buf.public_cert &&
setup_data->pki_key.key.pem_buf.public_cert_len &&
setup_data->pki_key.key.pem_buf.private_key &&
setup_data->pki_key.key.pem_buf.private_key_len > 0) {
mbedtls_x509_crt_init(public_cert);
mbedtls_pk_init(private_key);
ret = mbedtls_x509_crt_parse(public_cert,
(const unsigned char *)setup_data->pki_key.key.pem_buf.public_cert,
setup_data->pki_key.key.pem_buf.public_cert_len);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_x509_crt_parse returned -0x%x\n\n", -ret);
return ret;
}
ret = mbedtls_pk_parse_key(private_key,
(const unsigned char *)setup_data->pki_key.key.pem_buf.private_key,
setup_data->pki_key.key.pem_buf.private_key_len, NULL, 0);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_pk_parse_keyfile returned -0x%x\n\n", -ret);
return ret;
}
ret = mbedtls_ssl_conf_own_cert(&m_env->conf, public_cert, private_key);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_ssl_conf_own_cert returned -0x%x\n\n", -ret);
return ret;
}
} else if (role == COAP_DTLS_ROLE_SERVER) {
coap_log(LOG_ERR,
"***setup_pki: (D)TLS: No %s Certificate + Private "
"Key defined\n",
role == COAP_DTLS_ROLE_SERVER ? "Server" : "Client");
return -1;
}
if (setup_data->pki_key.key.pem_buf.ca_cert &&
setup_data->pki_key.key.pem_buf.ca_cert_len > 0) {
mbedtls_x509_crt_init(cacert);
ret = mbedtls_x509_crt_parse(cacert,
(const unsigned char *)setup_data->pki_key.key.pem_buf.ca_cert,
setup_data->pki_key.key.pem_buf.ca_cert_len);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_x509_crt_parse returned -0x%x\n\n", -ret);
return ret;
}
mbedtls_ssl_conf_authmode(&m_env->conf, setup_data->require_peer_cert ?
MBEDTLS_SSL_VERIFY_REQUIRED :
MBEDTLS_SSL_VERIFY_OPTIONAL);
mbedtls_ssl_conf_ca_chain(&m_env->conf, cacert, NULL);
}
break;
case COAP_PKI_KEY_ASN1:
if (setup_data->pki_key.key.asn1.public_cert &&
setup_data->pki_key.key.asn1.public_cert_len &&
setup_data->pki_key.key.asn1.private_key &&
setup_data->pki_key.key.asn1.private_key_len > 0) {
mbedtls_x509_crt_init(public_cert);
mbedtls_pk_init(private_key);
ret = mbedtls_x509_crt_parse(public_cert,
(const unsigned char *)setup_data->pki_key.key.asn1.public_cert,
setup_data->pki_key.key.asn1.public_cert_len);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_x509_crt_parse returned -0x%x\n\n", -ret);
return ret;
}
ret = mbedtls_pk_parse_key(private_key,
(const unsigned char *)setup_data->pki_key.key.asn1.private_key,
setup_data->pki_key.key.asn1.private_key_len, NULL, 0);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_pk_parse_keyfile returned -0x%x\n\n", -ret);
return ret;
}
ret = mbedtls_ssl_conf_own_cert(&m_env->conf, public_cert, private_key);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_ssl_conf_own_cert returned -0x%x\n\n", -ret);
return ret;
}
} else if (role == COAP_DTLS_ROLE_SERVER) {
coap_log(LOG_ERR,
"***setup_pki: (D)TLS: No %s Certificate + Private "
"Key defined\n",
role == COAP_DTLS_ROLE_SERVER ? "Server" : "Client");
return -1;
}
if (setup_data->pki_key.key.asn1.ca_cert &&
setup_data->pki_key.key.asn1.ca_cert_len > 0) {
mbedtls_x509_crt_init(cacert);
ret = mbedtls_x509_crt_parse(cacert,
(const unsigned char *)setup_data->pki_key.key.asn1.ca_cert,
setup_data->pki_key.key.asn1.ca_cert_len);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_x509_crt_parse returned -0x%x\n\n", -ret);
return ret;
}
mbedtls_ssl_conf_authmode(&m_env->conf, setup_data->require_peer_cert ?
MBEDTLS_SSL_VERIFY_REQUIRED :
MBEDTLS_SSL_VERIFY_OPTIONAL);
mbedtls_ssl_conf_ca_chain(&m_env->conf, cacert, NULL);
}
break;
default:
coap_log(LOG_ERR,
"***setup_pki: (D)TLS: Unknown key type %d\n",
setup_data->pki_key.key_type);
return -1;
}
if (m_context->root_ca_file) {
ret = mbedtls_x509_crt_parse_file(cacert, m_context->root_ca_file);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_x509_crt_parse returned -0x%x\n\n", -ret);
return ret;
}
mbedtls_ssl_conf_ca_chain(&m_env->conf, cacert, NULL);
}
if (m_context->root_ca_path) {
ret = mbedtls_x509_crt_parse_file(cacert, m_context->root_ca_path);
if (ret < 0) {
coap_log(LOG_ERR, "mbedtls_x509_crt_parse returned -0x%x\n\n", -ret);
return ret;
}
mbedtls_ssl_conf_ca_chain(&m_env->conf, cacert, NULL);
}
/*
* Verify Peer.
* Need to do all checking, even if setup_data->verify_peer_cert is not set
*/
mbedtls_ssl_conf_verify(&m_env->conf,
cert_verify_callback_mbedtls, c_session);
return 0;
}
/*
* PKI SNI callback.
*/
static int
pki_sni_callback(void *p_info, mbedtls_ssl_context *ssl,
const unsigned char *uname, size_t name_len)
{
unsigned int i;
coap_dtls_pki_t sni_setup_data;
coap_session_t *c_session = (coap_session_t *)p_info;
coap_mbedtls_env_t *m_env = (coap_mbedtls_env_t *)c_session->tls;
coap_mbedtls_context_t *m_context =
(coap_mbedtls_context_t *)c_session->context->dtls_context;
int ret = 0;
/* Is this a cached entry? */
for (i = 0; i < m_context->pki_sni_count; i++) {
if (name_len == strlen(m_context->pki_sni_entry_list[i].sni) &&
memcmp(uname, m_context->pki_sni_entry_list[i].sni, name_len) == 0) {
break;
}
}
if (i == m_context->pki_sni_count) {
/*
* New PKI SNI request
*/
char *name;
coap_dtls_key_t *new_entry;
name = mbedtls_malloc(name_len+1);
memcpy(name, uname, name_len);
name[name_len] = '\000';
new_entry =
m_context->setup_data.validate_sni_call_back(name,
m_context->setup_data.sni_call_back_arg);
if (!new_entry) {
ret = -1;
mbedtls_free(name);
goto end;
}
m_context->pki_sni_entry_list =
mbedtls_realloc(m_context->pki_sni_entry_list,
(i+1)*sizeof(pki_sni_entry));
m_context->pki_sni_entry_list[i].sni = name;
m_context->pki_sni_entry_list[i].pki_key = *new_entry;
sni_setup_data = m_context->setup_data;
sni_setup_data.pki_key = *new_entry;
if ((ret = setup_pki_credentials(&m_context->pki_sni_entry_list[i].cacert,
&m_context->pki_sni_entry_list[i].public_cert,
&m_context->pki_sni_entry_list[i].private_key,
m_env,
m_context,
c_session,
&sni_setup_data, COAP_DTLS_ROLE_SERVER)) < 0) {
ret = -1;
mbedtls_free(name);
goto end;
}
m_context->pki_sni_count++;
}
end:
if (ret != -1) {
mbedtls_ssl_set_hs_ca_chain(ssl, &m_context->pki_sni_entry_list[i].cacert,
NULL);
return mbedtls_ssl_set_hs_own_cert(ssl,
&m_context->pki_sni_entry_list[i].public_cert,
&m_context->pki_sni_entry_list[i].private_key);
}
return ret;
}
#ifdef PSK2_PR
/*
* PSK SNI callback.
*/
static int
psk_sni_callback(void *p_info, mbedtls_ssl_context *ssl,
const unsigned char *uname, size_t name_len)
{
unsigned int i;
coap_dtls_spsk_t sni_setup_data;
coap_session_t *c_session = (coap_session_t *)p_info;
coap_mbedtls_context_t *m_context =
(coap_mbedtls_context_t *)c_session->context->dtls_context;
int ret = 0;
/* Is this a cached entry? */
for (i = 0; i < m_context->psk_sni_count; i++) {
if (name_len == m_context->psk_sni_entry_list[i].sni.length &&
memcmp(uname, m_context->psk_sni_entry_list[i].sni.s, name_len) == 0) {
break;
}
}
if (i == m_context->psk_sni_count) {
/*
* New PSK SNI request
*/
coap_str_const_t lsni;
uint8_t *name;
const coap_dtls_spsk_info_t *new_entry;
name = mbedtls_malloc(name_len+1);
memcpy(name, uname, name_len);
name[name_len] = '\000';
lsni.s = name;
lsni.length = name_len;
new_entry =
c_session->context->spsk_setup_data.validate_sni_call_back(&lsni,
c_session,
c_session->context->spsk_setup_data.sni_call_back_arg);
if (!new_entry) {
ret = -1;
mbedtls_free(name);
goto end;
}
m_context->psk_sni_entry_list =
mbedtls_realloc(m_context->psk_sni_entry_list,
(i+1)*sizeof(psk_sni_entry));
m_context->psk_sni_entry_list[i].sni.s = name;
m_context->psk_sni_entry_list[i].sni.length = name_len;
m_context->psk_sni_entry_list[i].psk_info = *new_entry;
sni_setup_data = c_session->context->spsk_setup_data;
sni_setup_data.psk_info = *new_entry;
m_context->psk_sni_count++;
}
end:
if (ret != -1) {
coap_session_refresh_psk_hint(c_session,
&m_context->psk_sni_entry_list[i].psk_info.hint);
coap_session_refresh_psk_key(c_session,
&m_context->psk_sni_entry_list[i].psk_info.key);
return mbedtls_ssl_set_hs_psk(ssl,
m_context->psk_sni_entry_list[i].psk_info.key.s,
m_context->psk_sni_entry_list[i].psk_info.key.length);
}
return ret;
}
#endif /* PSK2_PR */
static int setup_server_ssl_session(coap_session_t *c_session,
coap_mbedtls_env_t *m_env)
{
coap_mbedtls_context_t *m_context =
(coap_mbedtls_context_t *)c_session->context->dtls_context;
int ret = 0;
m_context->psk_pki_enabled |= IS_SERVER;
mbedtls_ssl_cookie_init(&m_env->cookie_ctx);
if ((ret = mbedtls_ssl_config_defaults(&m_env->conf,
MBEDTLS_SSL_IS_SERVER,
c_session->proto == COAP_PROTO_DTLS ?
MBEDTLS_SSL_TRANSPORT_DATAGRAM :
MBEDTLS_SSL_TRANSPORT_STREAM,
MBEDTLS_SSL_PRESET_DEFAULT)) != 0) {
coap_log(LOG_ERR, "mbedtls_ssl_config_defaults returned -0x%x\n", -ret);
goto fail;
}
mbedtls_ssl_conf_rng(&m_env->conf, mbedtls_ctr_drbg_random, &m_env->ctr_drbg);
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS)
mbedtls_ssl_conf_handshake_timeout(&m_env->conf, 1000, 60000);
if (m_context->psk_pki_enabled & IS_PSK) {
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_PSK_MODES)
mbedtls_ssl_conf_psk_cb(&m_env->conf, psk_server_callback, c_session);
#ifdef PSK2_PR
if (c_session->context->spsk_setup_data.validate_sni_call_back) {
mbedtls_ssl_conf_sni(&m_env->conf, psk_sni_callback, c_session);
}
#endif /* PSK2_PR */
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_PSK_MODES */
}
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
if (m_context->psk_pki_enabled & IS_PKI) {
ret = setup_pki_credentials(&m_env->cacert, &m_env->public_cert,
&m_env->private_key, m_env, m_context,
c_session, &m_context->setup_data,
COAP_DTLS_ROLE_SERVER);
if (ret < 0) {
coap_log(LOG_ERR, "PKI setup failed\n");
return ret;
}
if (m_context->setup_data.validate_sni_call_back) {
mbedtls_ssl_conf_sni(&m_env->conf, pki_sni_callback, c_session);
}
}
if ((ret = mbedtls_ssl_cookie_setup(&m_env->cookie_ctx,
mbedtls_ctr_drbg_random,
&m_env->ctr_drbg)) != 0) {
coap_log(LOG_ERR, "mbedtls_ssl_cookie_setup: returned -0x%x\n", -ret);
goto fail;
}
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS)
mbedtls_ssl_conf_dtls_cookies(&m_env->conf, mbedtls_ssl_cookie_write,
mbedtls_ssl_cookie_check,
&m_env->cookie_ctx );
mbedtls_ssl_set_mtu(&m_env->ssl, c_session->mtu);
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
fail:
return ret;
}
#define MAX_CIPHERS 100
static int psk_ciphers[MAX_CIPHERS];
static int pki_ciphers[MAX_CIPHERS];
static int processed_ciphers = 0;
static void
set_ciphersuites(mbedtls_ssl_config *conf, int is_psk)
{
if (!processed_ciphers) {
const int *list = mbedtls_ssl_list_ciphersuites();
int *psk_list = psk_ciphers;
int *pki_list = pki_ciphers;
while (*list) {
const mbedtls_ssl_ciphersuite_t *cur =
mbedtls_ssl_ciphersuite_from_id(*list);
if (cur) {
if (mbedtls_ssl_ciphersuite_uses_psk(cur)) {
if (&psk_ciphers[MAX_CIPHERS] - psk_list > 1) {
*psk_list = *list;
psk_list++;
}
else {
static int done = 0;
if (!done) {
done = 1;
coap_log(LOG_ERR, "psk_ciphers[MAX_CIPHERS] insufficient\n");
}
}
}
else {
if (&pki_ciphers[MAX_CIPHERS] - pki_list > 1) {
*pki_list = *list;
pki_list++;
}
else {
static int done = 0;
if (!done) {
done = 1;
coap_log(LOG_ERR, "pki_ciphers[MAX_CIPHERS] insufficient\n");
}
}
}
}
list++;
}
/* zero terminate */
*psk_list = 0;
*pki_list = 0;
processed_ciphers = 1;
}
mbedtls_ssl_conf_ciphersuites(conf, is_psk ? psk_ciphers : pki_ciphers);
}
static int setup_client_ssl_session(coap_session_t *c_session,
coap_mbedtls_env_t *m_env)
{
int ret;
coap_mbedtls_context_t *m_context =
(coap_mbedtls_context_t *)c_session->context->dtls_context;
m_context->psk_pki_enabled |= IS_CLIENT;
if ((ret = mbedtls_ssl_config_defaults(&m_env->conf,
MBEDTLS_SSL_IS_CLIENT,
c_session->proto == COAP_PROTO_DTLS ?
MBEDTLS_SSL_TRANSPORT_DATAGRAM :
MBEDTLS_SSL_TRANSPORT_STREAM,
MBEDTLS_SSL_PRESET_DEFAULT)) != 0) {
coap_log(LOG_ERR, "mbedtls_ssl_config_defaults returned -0x%x", -ret);
goto fail;
}
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS)
mbedtls_ssl_conf_handshake_timeout(&m_env->conf, 1000, 60000);
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
mbedtls_ssl_conf_authmode(&m_env->conf, MBEDTLS_SSL_VERIFY_REQUIRED);
mbedtls_ssl_conf_rng(&m_env->conf, mbedtls_ctr_drbg_random, &m_env->ctr_drbg);
if (m_context->psk_pki_enabled & IS_PSK) {
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_PSK_MODES)
uint8_t identity[64];
size_t identity_len;
uint8_t psk_key[64];
size_t psk_len;
size_t max_identity_len = sizeof(identity);
coap_log(LOG_INFO, "Setting PSK key\n");
psk_len = c_session->context->get_client_psk(c_session,
NULL,
0,
identity,
&identity_len,
max_identity_len,
psk_key,
sizeof(psk_key));
assert(identity_len < sizeof(identity));
mbedtls_ssl_conf_psk(&m_env->conf, (const unsigned char *)psk_key,
psk_len, (const unsigned char *)identity,
identity_len);
#ifdef PSK2_PR
if (c_session->cpsk_setup_data.client_sni) {
mbedtls_ssl_set_hostname(&m_env->ssl,
c_session->cpsk_setup_data.client_sni);
}
#if 0
/* Identity Hint currently not supported in MbedTLS */
if (c_session->cpsk_setup_data.validate_ih_call_back) {
coap_log(LOG_DEBUG,
"CoAP Client restricted to (D)TLS1.2 with Identity Hint callback\n");
mbedtls_ssl_conf_max_version(&m_env->conf, MBEDTLS_SSL_MAJOR_VERSION_3,
MBEDTLS_SSL_MINOR_VERSION_3);
}
#endif
#endif /* PSK2_PR */
set_ciphersuites(&m_env->conf, 1);
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_PSK_MODES */
}
else if ((m_context->psk_pki_enabled & IS_PKI) ||
(m_context->psk_pki_enabled & (IS_PSK | IS_PKI)) == 0) {
/*
* If neither PSK or PKI have been set up, use PKI basics.
* This works providing COAP_PKI_KEY_PEM has a value of 0.
*/
if ((m_context->psk_pki_enabled & (IS_PSK | IS_PKI)) == 0) {
mbedtls_ssl_conf_authmode(&m_env->conf, MBEDTLS_SSL_VERIFY_OPTIONAL);
}
ret = setup_pki_credentials(&m_env->cacert, &m_env->public_cert,
&m_env->private_key, m_env, m_context,
c_session, &m_context->setup_data,
COAP_DTLS_ROLE_CLIENT);
if (ret < 0) {
coap_log(LOG_ERR, "PKI setup failed\n");
return ret;
}
if (c_session->proto == COAP_PROTO_TLS) {
const char *alpn_list[2];
memset(alpn_list, 0, sizeof(alpn_list));
alpn_list[0] = "coap";
ret = mbedtls_ssl_conf_alpn_protocols(&m_env->conf, alpn_list);
if (ret != 0) {
coap_log(LOG_ERR, "ALPN setup failed %d)\n", ret);
}
}
if (m_context->setup_data.client_sni) {
mbedtls_ssl_set_hostname(&m_env->ssl, m_context->setup_data.client_sni);
}
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS)
mbedtls_ssl_set_mtu(&m_env->ssl, c_session->mtu);
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
set_ciphersuites(&m_env->conf, 0);
}
return 0;
fail:
return ret;
}
static void mbedtls_cleanup(coap_mbedtls_env_t *m_env)
{
if (!m_env) {
return;
}
mbedtls_x509_crt_free(&m_env->cacert);
mbedtls_x509_crt_free(&m_env->public_cert);
mbedtls_pk_free(&m_env->private_key);
mbedtls_entropy_free(&m_env->entropy);
mbedtls_ssl_config_free(&m_env->conf);
mbedtls_ctr_drbg_free(&m_env->ctr_drbg);
mbedtls_ssl_free(&m_env->ssl);
mbedtls_ssl_cookie_free(&m_env->cookie_ctx);
}
static void
coap_dtls_free_mbedtls_env(coap_mbedtls_env_t *m_env) {
if (m_env) {
mbedtls_cleanup(m_env);
free(m_env);
}
}
/*
* return -1 failure
* 0 not completed
* 1 established
*/
static int do_mbedtls_handshake(coap_session_t *c_session,
coap_mbedtls_env_t *m_env) {
int ret;
char buf[128];
ret = mbedtls_ssl_handshake(&m_env->ssl);
switch (ret) {
case 0:
m_env->established = 1;
coap_log(LOG_DEBUG, "* %s: MbedTLS established\n",
coap_session_str(c_session));
ret = 1;
break;
case MBEDTLS_ERR_SSL_WANT_READ:
case MBEDTLS_ERR_SSL_WANT_WRITE:
errno = EAGAIN;
ret = 0;
break;
case MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED:
coap_log(LOG_INFO, "hello verification requested\n");
ret = -1;
mbedtls_ssl_session_reset(&m_env->ssl);
break;
case MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE:
c_session->dtls_event = COAP_EVENT_DTLS_CLOSED;
ret = -1;
break;
default:
mbedtls_strerror(ret, buf, sizeof(buf));
coap_log(LOG_WARNING,
"do_mbedtls_handshake: session establish "
"returned -0x%x: '%s'\n",
-ret, buf);
ret = -1;
break;
}
return ret;
}
static void
mbedtls_debug_out(void *ctx UNUSED, int level,
const char *file, int line, const char *str) {
int log_level;
switch (level) {
case 4:
case 3:
case 2:
log_level = LOG_DEBUG;
break;
case 1:
log_level = LOG_ERR;
break;
case 0:
default:
log_level = 0;
break;
}
coap_log(log_level, "%s:%04d: %s", file, line, str);
}
static coap_mbedtls_env_t *coap_dtls_new_mbedtls_env(coap_session_t *c_session,
coap_dtls_role_t role)
{
int ret = 0;
coap_mbedtls_env_t *m_env = (coap_mbedtls_env_t *)c_session->tls;
if (m_env)
return m_env;
m_env = (coap_mbedtls_env_t *)calloc(1, sizeof(coap_mbedtls_env_t));
if (!m_env) {
return NULL;
}
mbedtls_ssl_init(&m_env->ssl);
mbedtls_ctr_drbg_init(&m_env->ctr_drbg);
mbedtls_ssl_config_init(&m_env->conf);
mbedtls_entropy_init(&m_env->entropy);
#if defined(ESPIDF_VERSION) && defined(CONFIG_MBEDTLS_DEBUG)
mbedtls_esp_enable_debug_log(&m_env->conf, CONFIG_MBEDTLS_DEBUG_LEVEL);
#endif /* ESPIDF_VERSION && CONFIG_MBEDTLS_DEBUG */
if ((ret = mbedtls_ctr_drbg_seed(&m_env->ctr_drbg,
mbedtls_entropy_func, &m_env->entropy, NULL, 0)) != 0) {
coap_log(LOG_ERR, "mbedtls_ctr_drbg_seed returned -0x%x", -ret);
goto fail;
}
if (role == COAP_DTLS_ROLE_CLIENT) {
if (setup_client_ssl_session(c_session, m_env) != 0) {
goto fail;
}
} else if (role == COAP_DTLS_ROLE_SERVER) {
if (setup_server_ssl_session(c_session, m_env) != 0) {
goto fail;
}
} else {
goto fail;
}
if ((ret = mbedtls_ssl_setup(&m_env->ssl, &m_env->conf)) != 0) {
goto fail;
}
mbedtls_ssl_set_bio(&m_env->ssl, c_session, coap_dgram_write,
coap_dgram_read, NULL);
mbedtls_ssl_set_timer_cb(&m_env->ssl, &m_env->timer,
mbedtls_timing_set_delay,
mbedtls_timing_get_delay);
mbedtls_ssl_conf_dbg(&m_env->conf, mbedtls_debug_out, stdout);
return m_env;
fail:
if (m_env) {
free(m_env);
}
return NULL;
}
int coap_dtls_is_supported(void) {
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS)
return 1;
#else /* ESPIDF_VERSION && !CONFIG_MBEDTLS_SSL_PROTO_DTLS */
coap_log(LOG_EMERG,
"libcoap not compiled for DTLS with MbedTLS"
" - update MbedTLS to include DTLS\n");
return 0;
#endif /* ESPIDF_VERSION && !CONFIG_MBEDTLS_SSL_PROTO_DTLS */
}
int coap_tls_is_supported(void)
{
return 0;
}
void *coap_dtls_new_context(struct coap_context_t *c_context)
{
coap_mbedtls_context_t *m_context;
(void)c_context;
m_context = (coap_mbedtls_context_t *)calloc(1, sizeof(coap_mbedtls_context_t));
if (m_context) {
memset(m_context, 0, sizeof(coap_mbedtls_context_t));
}
return m_context;
}
#ifndef PSK2_PR
int coap_dtls_context_set_psk(struct coap_context_t *c_context,
const char *identity_hint UNUSED,
coap_dtls_role_t role UNUSED)
{
coap_mbedtls_context_t *m_context =
((coap_mbedtls_context_t *)c_context->dtls_context);
m_context->psk_pki_enabled |= IS_PSK;
return 1;
}
#else /* PSK2_PR */
/*
* return 0 failed
* 1 passed
*/
int
coap_dtls_context_set_spsk(coap_context_t *c_context,
coap_dtls_spsk_t *setup_data
) {
coap_mbedtls_context_t *m_context =
((coap_mbedtls_context_t *)c_context->dtls_context);
if (!m_context || !setup_data)
return 0;
m_context->psk_pki_enabled |= IS_PSK;
return 1;
}
/*
* return 0 failed
* 1 passed
*/
int
coap_dtls_context_set_cpsk(coap_context_t *c_context,
coap_dtls_cpsk_t *setup_data
) {
coap_mbedtls_context_t *m_context =
((coap_mbedtls_context_t *)c_context->dtls_context);
if (!m_context || !setup_data)
return 0;
if (setup_data->validate_ih_call_back) {
coap_log(LOG_WARNING,
"CoAP Client with MbedTLS does not support Identity Hint selection\n");
}
m_context->psk_pki_enabled |= IS_PSK;
return 1;
}
#endif /* PSK2_PR */
int coap_dtls_context_set_pki(struct coap_context_t *c_context,
coap_dtls_pki_t *setup_data,
coap_dtls_role_t role UNUSED)
{
coap_mbedtls_context_t *m_context =
((coap_mbedtls_context_t *)c_context->dtls_context);
m_context->setup_data = *setup_data;
m_context->psk_pki_enabled |= IS_PKI;
return 1;
}
int coap_dtls_context_set_pki_root_cas(struct coap_context_t *c_context,
const char *ca_file,
const char *ca_path)
{
coap_mbedtls_context_t *m_context =
((coap_mbedtls_context_t *)c_context->dtls_context);
if (!m_context) {
coap_log(LOG_WARNING,
"coap_context_set_pki_root_cas: (D)TLS environment "
"not set up\n");
return 0;
}
if (ca_file == NULL && ca_path == NULL) {
coap_log(LOG_WARNING,
"coap_context_set_pki_root_cas: ca_file and/or ca_path "
"not defined\n");
return 0;
}
if (m_context->root_ca_file) {
free(m_context->root_ca_file);
m_context->root_ca_file = NULL;
}
if (ca_file) {
m_context->root_ca_file = mbedtls_strdup(ca_file);
}
if (m_context->root_ca_path) {
free(m_context->root_ca_path);
m_context->root_ca_path = NULL;
}
if (ca_path) {
m_context->root_ca_path = mbedtls_strdup(ca_path);
}
return 1;
}
int coap_dtls_context_check_keys_enabled(struct coap_context_t *c_context)
{
coap_mbedtls_context_t *m_context =
((coap_mbedtls_context_t *)c_context->dtls_context);
return m_context->psk_pki_enabled ? 1 : 0;
}
void coap_dtls_free_context(void *dtls_context)
{
coap_mbedtls_context_t *m_context = (coap_mbedtls_context_t *)dtls_context;
unsigned int i;
for (i = 0; i < m_context->pki_sni_count; i++) {
mbedtls_free(m_context->pki_sni_entry_list[i].sni);
mbedtls_x509_crt_free(&m_context->pki_sni_entry_list[i].public_cert);
mbedtls_pk_free(&m_context->pki_sni_entry_list[i].private_key);
mbedtls_x509_crt_free(&m_context->pki_sni_entry_list[i].cacert);
}
#ifdef PSK2_PR
for (i = 0; i < m_context->psk_sni_count; i++) {
mbedtls_free(m_context->psk_sni_entry_list[i].sni.s);
}
if (m_context->psk_sni_entry_list)
mbedtls_free(m_context->pki_sni_entry_list);
#endif /* PSK2_PR */
free(m_context);
}
void *coap_dtls_new_client_session(coap_session_t *c_session)
{
coap_mbedtls_env_t *m_env = coap_dtls_new_mbedtls_env(c_session,
COAP_DTLS_ROLE_CLIENT);
int ret;
if (m_env) {
ret = do_mbedtls_handshake(c_session, m_env);
if (ret == -1) {
coap_dtls_free_mbedtls_env(m_env);
return NULL;
}
}
return m_env;
}
void *coap_dtls_new_server_session(coap_session_t *c_session)
{
coap_mbedtls_env_t *m_env =
(coap_mbedtls_env_t *)c_session->tls;
if (m_env) {
m_env->seen_client_hello = 1;
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS)
mbedtls_ssl_set_mtu(&m_env->ssl, c_session->mtu);
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
}
return m_env;
}
void coap_dtls_free_session(coap_session_t *c_session)
{
if (c_session && c_session->context) {
coap_dtls_free_mbedtls_env(c_session->tls);
c_session->tls = NULL;
}
return;
}
void coap_dtls_session_update_mtu(coap_session_t *c_session)
{
#if !defined(ESPIDF_VERSION) || defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS)
coap_mbedtls_env_t *m_env =
(coap_mbedtls_env_t *)c_session->tls;
if (m_env) {
mbedtls_ssl_set_mtu(&m_env->ssl, c_session->mtu);
}
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
}
int coap_dtls_send(coap_session_t *c_session,
const uint8_t *data,
size_t data_len)
{
int ret;
coap_mbedtls_env_t *m_env = (coap_mbedtls_env_t *)c_session->tls;
char buf[128];
assert(m_env != NULL);
if (!m_env) {
return -1;
}
c_session->dtls_event = -1;
if (m_env->established) {
ret = mbedtls_ssl_write(&m_env->ssl, (const unsigned char*) data, data_len);
if (ret <= 0) {
switch (ret) {
case MBEDTLS_ERR_SSL_WANT_READ:
case MBEDTLS_ERR_SSL_WANT_WRITE:
ret = 0;
break;
case MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE:
c_session->dtls_event = COAP_EVENT_DTLS_CLOSED;
ret = -1;
break;
default:
mbedtls_strerror(ret, buf, sizeof(buf));
coap_log(LOG_WARNING,
"coap_dtls_send: "
"returned -0x%x: '%s'\n",
-ret, buf);
ret = -1;
break;
}
if (ret == -1) {
coap_log(LOG_WARNING, "coap_dtls_send: cannot send PDU\n");
}
}
} else {
ret = do_mbedtls_handshake(c_session, m_env);
if (ret == 1) {
/* Just connected, so send the data */
return coap_dtls_send(c_session, data, data_len);
}
ret = -1;
}
if (c_session->dtls_event >= 0) {
coap_handle_event(c_session->context, c_session->dtls_event, c_session);
if (c_session->dtls_event == COAP_EVENT_DTLS_ERROR ||
c_session->dtls_event == COAP_EVENT_DTLS_CLOSED) {
coap_session_disconnected(c_session, COAP_NACK_TLS_FAILED);
ret = -1;
}
}
return ret;
}
int coap_dtls_is_context_timeout(void)
{
return 0;
}
coap_tick_t coap_dtls_get_context_timeout(void *dtls_context UNUSED)
{
return 0;
}
coap_tick_t coap_dtls_get_timeout(coap_session_t *c_session, coap_tick_t now)
{
coap_mbedtls_env_t *m_env = (coap_mbedtls_env_t *)c_session->tls;
int ret = mbedtls_timing_get_delay(&m_env->timer);
switch (ret) {
case 0:
case 1:
/* int_ms has timed out, but not fin_ms */
return now + 1;
case 2:
/* fin_ms has timed out - time for a retry */
return now;
default:
break;
}
return 0;
}
void coap_dtls_handle_timeout(coap_session_t *c_session)
{
coap_mbedtls_env_t *m_env = (coap_mbedtls_env_t *)c_session->tls;
assert(m_env != NULL);
if (((c_session->state == COAP_SESSION_STATE_HANDSHAKE) &&
(++c_session->dtls_timeout_count > c_session->max_retransmit)) ||
(do_mbedtls_handshake(c_session, m_env) < 0)) {
/* Too many retries */
coap_session_disconnected(c_session, COAP_NACK_TLS_FAILED);
}
return;
}
int coap_dtls_receive(coap_session_t *c_session,
const uint8_t *data,
size_t data_len)
{
int ret = 1;
c_session->dtls_event = -1;
coap_mbedtls_env_t *m_env = (coap_mbedtls_env_t *)c_session->tls;
assert(m_env != NULL);
coap_ssl_t *ssl_data = &m_env->coap_ssl_data;
if (ssl_data->pdu_len) {
coap_log(LOG_INFO, "** %s: Previous data not read %u bytes\n",
coap_session_str(c_session), ssl_data->pdu_len);
}
ssl_data->pdu = data;
ssl_data->pdu_len = (unsigned)data_len;
if (m_env->established) {
#if COAP_CONSTRAINED_STACK
static coap_mutex_t b_static_mutex = COAP_MUTEX_INITIALIZER;
static uint8_t pdu[COAP_RXBUFFER_SIZE];
#else /* ! COAP_CONSTRAINED_STACK */
uint8_t pdu[COAP_RXBUFFER_SIZE];
#endif /* ! COAP_CONSTRAINED_STACK */
#if COAP_CONSTRAINED_STACK
coap_mutex_lock(&b_static_mutex);
#endif /* COAP_CONSTRAINED_STACK */
if (c_session->state == COAP_SESSION_STATE_HANDSHAKE) {
coap_handle_event(c_session->context, COAP_EVENT_DTLS_CONNECTED,
c_session);
coap_session_connected(c_session);
}
ret = mbedtls_ssl_read(&m_env->ssl, pdu, (int)sizeof(pdu));
if (ret > 0) {
ret = coap_handle_dgram(c_session->context, c_session, pdu, (size_t)ret);
#if COAP_CONSTRAINED_STACK
coap_mutex_unlock(&b_static_mutex);
#endif /* COAP_CONSTRAINED_STACK */
return ret;
}
else if (ret == 0 || ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY) {
c_session->dtls_event = COAP_EVENT_DTLS_CLOSED;
}
else if (ret != MBEDTLS_ERR_SSL_WANT_READ) {
char buf[128];
mbedtls_strerror(ret, buf, sizeof(buf));
coap_log(LOG_WARNING,
"coap_dtls_receive: "
"returned -0x%x: '%s' (length %zd)\n",
-ret, buf, data_len);
}
#if COAP_CONSTRAINED_STACK
coap_mutex_unlock(&b_static_mutex);
#endif /* COAP_CONSTRAINED_STACK */
ret = -1;
}
else {
ret = do_mbedtls_handshake(c_session, m_env);
if (ret == 1) {
/* Just connected, so send the data */
coap_session_connected(c_session);
} else {
if (ssl_data->pdu_len) {
/* Do the handshake again incase of internal timeout */
ret = do_mbedtls_handshake(c_session, m_env);
if (ret == 1) {
/* Just connected, so send the data */
coap_session_connected(c_session);
} else {
ret = -1;
}
}
ret = -1;
}
}
if (c_session->dtls_event >= 0) {
coap_handle_event(c_session->context, c_session->dtls_event, c_session);
if (c_session->dtls_event == COAP_EVENT_DTLS_ERROR ||
c_session->dtls_event == COAP_EVENT_DTLS_CLOSED) {
coap_session_disconnected(c_session, COAP_NACK_TLS_FAILED);
ret = -1;
}
}
return ret;
}
int coap_dtls_hello(coap_session_t *c_session,
const uint8_t *data,
size_t data_len)
{
#if defined(ESPIDF_VERSION) && !defined(CONFIG_MBEDTLS_SSL_PROTO_DTLS)
(void)c_session;
(void)data;
(void)data_len;
return -1;
#else /* !ESPIDF_VERSION) || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
coap_mbedtls_env_t *m_env = (coap_mbedtls_env_t *)c_session->tls;
coap_ssl_t *ssl_data = m_env ? &m_env->coap_ssl_data : NULL;
int ret;
if (m_env) {
char *str = get_ip_addr(&c_session->remote_addr);
if (!str) {
return -1;
}
if((ret = mbedtls_ssl_set_client_transport_id(&m_env->ssl,
(unsigned char *)str, strlen(str))) != 0) {
coap_log(LOG_ERR,
"mbedtls_ssl_set_client_transport_id() returned -0x%x\n\n",
-ret);
free(str);
return -1;
}
free(str);
}
if (!m_env) {
m_env = coap_dtls_new_mbedtls_env(c_session, COAP_DTLS_ROLE_SERVER);
if (m_env) {
c_session->tls = m_env;
ssl_data = &m_env->coap_ssl_data;
ssl_data->pdu = data;
ssl_data->pdu_len = (unsigned)data_len;
char *str = get_ip_addr(&c_session->remote_addr);
if (!str) {
return -1;
}
if((ret = mbedtls_ssl_set_client_transport_id(&m_env->ssl,
(unsigned char *)str, strlen(str)) ) != 0) {
coap_log(LOG_ERR,
"mbedtls_ssl_set_client_transport_id() returned -0x%x\n",
-ret);
free(str);
return -1;
}
ret = do_mbedtls_handshake(c_session, m_env);
if (ret == 0 || m_env->seen_client_hello) {
m_env->seen_client_hello = 0;
free(str);
return 1;
}
free(str);
}
return 0;
}
ssl_data->pdu = data;
ssl_data->pdu_len = (unsigned)data_len;
ret = do_mbedtls_handshake(c_session, m_env);
if (ret == 0 || m_env->seen_client_hello) {
/* The test for seen_client_hello gives the ability to setup a new
c_session to continue the do_mbedtls_handshake past the client hello
and safely allow updating of the m_env and separately
letting a new session cleanly start up.
*/
m_env->seen_client_hello = 0;
return 1;
}
return 0;
#endif /* !ESPIDF_VERSION || CONFIG_MBEDTLS_SSL_PROTO_DTLS */
}
unsigned int coap_dtls_get_overhead(coap_session_t *c_session UNUSED)
{
return 13 + 8 + 8;
}
void *coap_tls_new_client_session(coap_session_t *c_session UNUSED, int *connected UNUSED)
{
return NULL;
}
void *coap_tls_new_server_session(coap_session_t *c_session UNUSED, int *connected UNUSED)
{
return NULL;
}
void coap_tls_free_session( coap_session_t *c_session UNUSED)
{
return;
}
ssize_t coap_tls_write(coap_session_t *c_session UNUSED,
const uint8_t *data UNUSED,
size_t data_len UNUSED
)
{
return 0;
}
ssize_t coap_tls_read(coap_session_t *c_session UNUSED,
uint8_t *data UNUSED,
size_t data_len UNUSED
)
{
return 0;
}
void coap_dtls_startup(void)
{
return;
}
static int keep_log_level = 0;
void coap_dtls_set_log_level(int level)
{
#if !defined(ESPIDF_VERSION)
int use_level;
/*
* MbedTLS debug levels filter
* 0 No debug
* 1 Error
* 2 State change
* 3 Informational
* 4 Verbose
*/
if (level <= LOG_ERR) {
use_level = 1;
}
else {
use_level = (level >= LOG_DEBUG) ? level - LOG_DEBUG + 2 : 0;
}
mbedtls_debug_set_threshold(use_level);
#endif /* !ESPIDF_VERSION) */
keep_log_level = level;
return;
}
int coap_dtls_get_log_level(void)
{
return keep_log_level;
}
coap_tls_version_t * coap_get_tls_library_version(void)
{
static coap_tls_version_t version;
version.version = mbedtls_version_get_number();
version.built_version = MBEDTLS_VERSION_NUMBER;
version.type = COAP_TLS_LIBRARY_MBEDTLS;
return &version;
}
#else /* !HAVE_MBEDTLS */
#ifdef __clang__
/* Make compilers happy that do not like empty modules. As this function is
* never used, we ignore -Wunused-function at the end of compiling this file
*/
#pragma GCC diagnostic ignored "-Wunused-function"
#endif
static inline void dummy(void) {
}
#endif /* HAVE_MBEDTLS */