C++ wpabuf_mhead函数代码示例

struct wpabuf * eap_sim_msg_finish(struct eap_sim_msg *msg, const u8 *k_aut,
				   const u8 *extra, size_t extra_len)
{
	struct eap_hdr *eap;
	struct wpabuf *buf;

	if (msg == NULL)
		return NULL;

	eap = wpabuf_mhead(msg->buf);
	eap->length = host_to_be16(wpabuf_len(msg->buf));

#if defined(EAP_AKA_PRIME) || defined(EAP_SERVER_AKA_PRIME)
	if (k_aut && msg->mac && msg->type == EAP_TYPE_AKA_PRIME) {
		eap_sim_add_mac_sha256(k_aut, (u8 *) wpabuf_head(msg->buf),
				       wpabuf_len(msg->buf),
				       (u8 *) wpabuf_mhead(msg->buf) +
				       msg->mac, extra, extra_len);
	} else
#endif /* EAP_AKA_PRIME || EAP_SERVER_AKA_PRIME */
	if (k_aut && msg->mac) {
		eap_sim_add_mac(k_aut, (u8 *) wpabuf_head(msg->buf),
				wpabuf_len(msg->buf),
				(u8 *) wpabuf_mhead(msg->buf) + msg->mac,
				extra, extra_len);
	}

	buf = msg->buf;
	os_free(msg);
	return buf;
}

/**
 * dh_derive_shared - Derive shared Diffie-Hellman key
 * @peer_public: Diffie-Hellman public value from peer
 * @own_private: Diffie-Hellman private key from dh_init()
 * @dh: Selected Diffie-Hellman group
 * Returns: Diffie-Hellman shared key
 */
struct wpabuf * dh_derive_shared(const struct wpabuf *peer_public,
				 const struct wpabuf *own_private,
				 const struct dh_group *dh)
{
	struct wpabuf *shared;
	size_t shared_len;

	if (dh == NULL || peer_public == NULL || own_private == NULL)
		return NULL;

	shared_len = dh->prime_len;
	shared = wpabuf_alloc(shared_len);
	if (shared == NULL)
		return NULL;
	if (crypto_mod_exp(wpabuf_head(peer_public), wpabuf_len(peer_public),
			   wpabuf_head(own_private), wpabuf_len(own_private),
			   dh->prime, dh->prime_len,
			   wpabuf_mhead(shared), &shared_len) < 0) {
		wpabuf_free(shared);
		wpa_printf(MSG_INFO, "DH: crypto_mod_exp failed");
		return NULL;
	}
	wpabuf_put(shared, shared_len);
	wpa_hexdump_buf_key(MSG_DEBUG, "DH: shared key", shared);

	return shared;
}

static int eap_fast_encrypt_phase2(struct eap_sm *sm,
				   struct eap_fast_data *data,
				   struct wpabuf *plain, int piggyback)
{
	struct wpabuf *encr;

	wpa_hexdump_buf_key(MSG_DEBUG, "EAP-FAST: Encrypting Phase 2 TLVs",
			    plain);
	encr = eap_server_tls_encrypt(sm, &data->ssl, wpabuf_mhead(plain),
				      wpabuf_len(plain));
	wpabuf_free(plain);

	if (data->ssl.out_buf && piggyback) {
		wpa_printf(MSG_DEBUG, "EAP-FAST: Piggyback Phase 2 data "
			   "(len=%d) with last Phase 1 Message (len=%d "
			   "used=%d)",
			   (int) wpabuf_len(encr),
			   (int) wpabuf_len(data->ssl.out_buf),
			   (int) data->ssl.out_used);
		if (wpabuf_resize(&data->ssl.out_buf, wpabuf_len(encr)) < 0) {
			wpa_printf(MSG_WARNING, "EAP-FAST: Failed to resize "
				   "output buffer");
			wpabuf_free(encr);
			return -1;
		}
		wpabuf_put_buf(data->ssl.out_buf, encr);
		wpabuf_free(encr);
	} else {
		wpabuf_free(data->ssl.out_buf);
		data->ssl.out_used = 0;
		data->ssl.out_buf = encr;
	}

	return 0;
}

struct wpabuf * ndef_build_wifi(struct wpabuf *buf)
{
	return ndef_build_record(FLAG_MESSAGE_BEGIN | FLAG_MESSAGE_END |
				 FLAG_TNF_RFC2046, wifi_handover_type,
				 os_strlen(wifi_handover_type), NULL, 0,
				 wpabuf_mhead(buf), wpabuf_len(buf));
}

static struct wpabuf * read_ufd(void *priv)
{
	struct wps_ufd_data *data = priv;
	struct wpabuf *buf;
	struct stat s;
	size_t file_size;

	if (fstat(data->ufd_fd, &s) < 0) {
		wpa_printf(MSG_ERROR, "WPS (UFD): Failed to get file size");
		return NULL;
	}

	file_size = s.st_size;
	buf = wpabuf_alloc(file_size);
	if (buf == NULL) {
		wpa_printf(MSG_ERROR, "WPS (UFD): Failed to alloc read "
			   "buffer");
		return NULL;
	}

	if (read(data->ufd_fd, wpabuf_mhead(buf), file_size) !=
	    (int) file_size) {
		wpabuf_free(buf);
		wpa_printf(MSG_ERROR, "WPS (UFD): Failed to read");
		return NULL;
	}
	wpabuf_put(buf, file_size);
	return buf;
}

void wpabuf_clear_free(struct wpabuf *buf)
{
	if (buf) {
		os_memset(wpabuf_mhead(buf), 0, wpabuf_len(buf));
		wpabuf_free(buf);
	}
}

struct radius_attr_hdr *radius_msg_add_attr(struct radius_msg *msg, u8 type,
					    const u8 *data, size_t data_len)
{
	size_t buf_needed;
	struct radius_attr_hdr *attr;

	if (data_len > RADIUS_MAX_ATTR_LEN) {
		printf("radius_msg_add_attr: too long attribute (%lu bytes)\n",
		       (unsigned long) data_len);
		return NULL;
	}

	buf_needed = sizeof(*attr) + data_len;

	if (wpabuf_tailroom(msg->buf) < buf_needed) {
		/* allocate more space for message buffer */
		if (wpabuf_resize(&msg->buf, buf_needed) < 0)
			return NULL;
		msg->hdr = wpabuf_mhead(msg->buf);
	}

	attr = wpabuf_put(msg->buf, sizeof(struct radius_attr_hdr));
	attr->type = type;
	attr->length = sizeof(*attr) + data_len;
	wpabuf_put_data(msg->buf, data, data_len);

	if (radius_msg_add_attr_to_array(msg, attr))
		return NULL;

	return attr;
}

static struct wpabuf * gnutls_get_appl_data(struct tls_connection *conn)
{
	int res;
	struct wpabuf *ad;
	wpa_printf(MSG_DEBUG, "GnuTLS: Check for possible Application Data");
	ad = wpabuf_alloc((wpabuf_len(conn->pull_buf) + 500) * 3);
	if (ad == NULL)
		return NULL;

	res = gnutls_record_recv(conn->session, wpabuf_mhead(ad),
				 wpabuf_size(ad));
	wpa_printf(MSG_DEBUG, "GnuTLS: gnutls_record_recv: %d", res);
	if (res < 0) {
		wpa_printf(MSG_DEBUG, "%s - gnutls_record_recv failed: %d "
			   "(%s)", __func__, (int) res,
			   gnutls_strerror(res));
		wpabuf_free(ad);
		return NULL;
	}

	wpabuf_put(ad, res);
	wpa_printf(MSG_DEBUG, "GnuTLS: Received %d bytes of Application Data",
		   res);
	return ad;
}

void eap_update_len(struct wpabuf *msg)
{
	struct eap_hdr *hdr;
	hdr = wpabuf_mhead(msg);
	if (wpabuf_len(msg) < sizeof(*hdr))
		return;
	hdr->length = host_to_be16(wpabuf_len(msg));
}

void ikev2_update_hdr(struct wpabuf *msg)
{
	struct ikev2_hdr *hdr;

	/* Update lenth field in HDR */
	hdr = wpabuf_mhead(msg);
	WPA_PUT_BE32(hdr->length, wpabuf_len(msg));
}

struct wpabuf * tls_connection_encrypt(void *tls_ctx,
				       struct tls_connection *conn,
				       const struct wpabuf *in_data)
{
#ifdef CONFIG_TLS_INTERNAL_CLIENT
	if (conn->client) {
		struct wpabuf *buf;
		int res;
		buf = wpabuf_alloc(wpabuf_len(in_data) + 300);
		if (buf == NULL)
			return NULL;
		res = tlsv1_client_encrypt(conn->client, wpabuf_head(in_data),
					   wpabuf_len(in_data),
					   wpabuf_mhead(buf),
					   wpabuf_size(buf));
		if (res < 0) {
			wpabuf_free(buf);
			return NULL;
		}
		wpabuf_put(buf, res);
		return buf;
	}
#endif /* CONFIG_TLS_INTERNAL_CLIENT */
#ifdef CONFIG_TLS_INTERNAL_SERVER
	if (conn->server) {
		struct wpabuf *buf;
		int res;
		buf = wpabuf_alloc(wpabuf_len(in_data) + 300);
		if (buf == NULL)
			return NULL;
		res = tlsv1_server_encrypt(conn->server, wpabuf_head(in_data),
					   wpabuf_len(in_data),
					   wpabuf_mhead(buf),
					   wpabuf_size(buf));
		if (res < 0) {
			wpabuf_free(buf);
			return NULL;
		}
		wpabuf_put(buf, res);
		return buf;
	}
#endif /* CONFIG_TLS_INTERNAL_SERVER */
	return NULL;
}

/**
 * dh_init - Initialize Diffie-Hellman handshake
 * @dh: Selected Diffie-Hellman group
 * @priv: Pointer for returning Diffie-Hellman private key
 * Returns: Diffie-Hellman public value
 */
struct wpabuf * dh_init(const struct dh_group *dh, struct wpabuf **priv)
{
	struct wpabuf *pv;
	size_t pv_len;
	int retval = 1;

	if (dh == NULL)
		return NULL;

	wpabuf_free(*priv);
	*priv = wpabuf_alloc(dh->prime_len);
	if (*priv == NULL)
		return NULL;

	if(get_dh_small())
	{
		/* Use small DH secret (1) to reduce calculation time on AP */
		if(!memset(wpabuf_put(*priv, 1), 1, 1))
			retval = 0;
	}
	else
	{
		if(os_get_random(wpabuf_put(*priv, dh->prime_len), dh->prime_len))
			retval = 0;
	}
	
	if(!retval)
	{	
		wpabuf_free(*priv);
		*priv = NULL;
		return NULL;
	}

	if (os_memcmp(wpabuf_head(*priv), dh->prime, dh->prime_len) > 0) {
		/* Make sure private value is smaller than prime */
		*(wpabuf_mhead_u8(*priv)) = 0;
	}
	wpa_hexdump_buf_key(/*MSG_INFO*/ MSG_DEBUG, "DH: private value", *priv);

	pv_len = dh->prime_len;
	pv = wpabuf_alloc(pv_len);
	if (pv == NULL)
		return NULL;
	if (crypto_mod_exp(dh->generator, dh->generator_len,
			   wpabuf_head(*priv), wpabuf_len(*priv),
			   dh->prime, dh->prime_len, wpabuf_mhead(pv),
			   &pv_len) < 0) {
		wpabuf_free(pv);
		wpa_printf(MSG_INFO, "DH: crypto_mod_exp failed");
		return NULL;
	}
	wpabuf_put(pv, pv_len);
	wpa_hexdump_buf(MSG_DEBUG, "DH: public value", pv);

	return pv;
}

static int write_ufd(void *priv, struct wpabuf *buf)
{
	struct wps_ufd_data *data = priv;

	if (write(data->ufd_fd, wpabuf_mhead(buf), wpabuf_len(buf)) !=
	    (int) wpabuf_len(buf)) {
		wpa_printf(MSG_ERROR, "WPS (UFD): Failed to write");
		return -1;
	}
	return 0;
}

void ext_password_free(struct wpabuf *pw)
{
	if (pw == NULL) {
		return;
	}
	os_memset(wpabuf_mhead(pw), 0, wpabuf_len(pw));
#ifdef __linux__
	if (munlock(wpabuf_head(pw), wpabuf_len(pw)) < 0) {
		wpa_printf(MSG_ERROR, "EXT PW: munlock failed: %s", strerror(errno));
	}
#endif							/* __linux__ */
	wpabuf_free(pw);
}

struct wpabuf * eap_sim_msg_finish(struct eap_sim_msg *msg, const u8 *k_aut,
				   const u8 *extra, size_t extra_len)
{
	struct eap_hdr *eap;
	struct wpabuf *buf;

	if (msg == NULL)
		return NULL;

	eap = wpabuf_mhead(msg->buf);
	eap->length = host_to_be16(wpabuf_len(msg->buf));

	if (k_aut && msg->mac) {
		eap_sim_add_mac(k_aut, (u8 *) wpabuf_head(msg->buf),
				wpabuf_len(msg->buf),
				(u8 *) wpabuf_mhead(msg->buf) + msg->mac,
				extra, extra_len);
	}

	buf = msg->buf;
	os_free(msg);
	return buf;
}