diff options
Diffstat (limited to 'net/nfc/llcp/commands.c')
| -rw-r--r-- | net/nfc/llcp/commands.c | 399 | 
1 files changed, 399 insertions, 0 deletions
diff --git a/net/nfc/llcp/commands.c b/net/nfc/llcp/commands.c new file mode 100644 index 000000000000..151f2ef429c4 --- /dev/null +++ b/net/nfc/llcp/commands.c @@ -0,0 +1,399 @@ +/* + * Copyright (C) 2011  Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the + * Free Software Foundation, Inc., + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#define pr_fmt(fmt) "llcp: %s: " fmt, __func__ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/nfc.h> + +#include <net/nfc/nfc.h> + +#include "../nfc.h" +#include "llcp.h" + +static u8 llcp_tlv_length[LLCP_TLV_MAX] = { +	0, +	1, /* VERSION */ +	2, /* MIUX */ +	2, /* WKS */ +	1, /* LTO */ +	1, /* RW */ +	0, /* SN */ +	1, /* OPT */ +	0, /* SDREQ */ +	2, /* SDRES */ + +}; + +static u8 llcp_tlv8(u8 *tlv, u8 type) +{ +	if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]]) +		return 0; + +	return tlv[2]; +} + +static u8 llcp_tlv16(u8 *tlv, u8 type) +{ +	if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]]) +		return 0; + +	return be16_to_cpu(*((__be16 *)(tlv + 2))); +} + + +static u8 llcp_tlv_version(u8 *tlv) +{ +	return llcp_tlv8(tlv, LLCP_TLV_VERSION); +} + +static u16 llcp_tlv_miux(u8 *tlv) +{ +	return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7f; +} + +static u16 llcp_tlv_wks(u8 *tlv) +{ +	return llcp_tlv16(tlv, LLCP_TLV_WKS); +} + +static u16 llcp_tlv_lto(u8 *tlv) +{ +	return llcp_tlv8(tlv, LLCP_TLV_LTO); +} + +static u8 llcp_tlv_opt(u8 *tlv) +{ +	return llcp_tlv8(tlv, LLCP_TLV_OPT); +} + +static u8 llcp_tlv_rw(u8 *tlv) +{ +	return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf; +} + +u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length) +{ +	u8 *tlv, length; + +	pr_debug("type %d\n", type); + +	if (type >= LLCP_TLV_MAX) +		return NULL; + +	length = llcp_tlv_length[type]; +	if (length == 0 && value_length == 0) +		return NULL; +	else +		length = value_length; + +	*tlv_length = 2 + length; +	tlv = kzalloc(2 + length, GFP_KERNEL); +	if (tlv == NULL) +		return tlv; + +	tlv[0] = type; +	tlv[1] = length; +	memcpy(tlv + 2, value, length); + +	return tlv; +} + +int nfc_llcp_parse_tlv(struct nfc_llcp_local *local, +			u8 *tlv_array, u16 tlv_array_len) +{ +	u8 *tlv = tlv_array, type, length, offset = 0; + +	pr_debug("TLV array length %d\n", tlv_array_len); + +	if (local == NULL) +		return -ENODEV; + +	while (offset < tlv_array_len) { +		type = tlv[0]; +		length = tlv[1]; + +		pr_debug("type 0x%x length %d\n", type, length); + +		switch (type) { +		case LLCP_TLV_VERSION: +			local->remote_version = llcp_tlv_version(tlv); +			break; +		case LLCP_TLV_MIUX: +			local->remote_miu = llcp_tlv_miux(tlv) + 128; +			break; +		case LLCP_TLV_WKS: +			local->remote_wks = llcp_tlv_wks(tlv); +			break; +		case LLCP_TLV_LTO: +			local->remote_lto = llcp_tlv_lto(tlv) * 10; +			break; +		case LLCP_TLV_OPT: +			local->remote_opt = llcp_tlv_opt(tlv); +			break; +		case LLCP_TLV_RW: +			local->remote_rw = llcp_tlv_rw(tlv); +			break; +		default: +			pr_err("Invalid gt tlv value 0x%x\n", type); +			break; +		} + +		offset += length + 2; +		tlv += length + 2; +	} + +	pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x rw %d\n", +		local->remote_version, local->remote_miu, +		local->remote_lto, local->remote_opt, +		local->remote_wks, local->remote_rw); + +	return 0; +} + +static struct sk_buff *llcp_add_header(struct sk_buff *pdu, +					u8 dsap, u8 ssap, u8 ptype) +{ +	u8 header[2]; + +	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap); + +	header[0] = (u8)((dsap << 2) | (ptype >> 2)); +	header[1] = (u8)((ptype << 6) | ssap); + +	pr_debug("header 0x%x 0x%x\n", header[0], header[1]); + +	memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE); + +	return pdu; +} + +static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv, u8 tlv_length) +{ +	/* XXX Add an skb length check */ + +	if (tlv == NULL) +		return NULL; + +	memcpy(skb_put(pdu, tlv_length), tlv, tlv_length); + +	return pdu; +} + +static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock, +							u8 cmd, u16 size) +{ +	struct sk_buff *skb; +	int err; + +	if (sock->ssap == 0) +		return NULL; + +	skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT, +					size + LLCP_HEADER_SIZE, &err); +	if (skb == NULL) { +		pr_err("Could not allocate PDU\n"); +		return NULL; +	} + +	skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd); + +	return skb; +} + +int nfc_llcp_disconnect(struct nfc_llcp_sock *sock) +{ +	struct sk_buff *skb; +	struct nfc_dev *dev; +	struct nfc_llcp_local *local; +	u16 size = 0; + +	pr_debug("Sending DISC\n"); + +	local = sock->local; +	if (local == NULL) +		return -ENODEV; + +	dev = sock->dev; +	if (dev == NULL) +		return -ENODEV; + +	size += LLCP_HEADER_SIZE; +	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; + +	skb = alloc_skb(size, GFP_ATOMIC); +	if (skb == NULL) +		return -ENOMEM; + +	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); + +	skb = llcp_add_header(skb, sock->ssap, sock->dsap, LLCP_PDU_DISC); + +	skb_queue_tail(&local->tx_queue, skb); + +	return 0; +} + +int nfc_llcp_send_symm(struct nfc_dev *dev) +{ +	struct sk_buff *skb; +	struct nfc_llcp_local *local; +	u16 size = 0; + +	pr_debug("Sending SYMM\n"); + +	local = nfc_llcp_find_local(dev); +	if (local == NULL) +		return -ENODEV; + +	size += LLCP_HEADER_SIZE; +	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; + +	skb = alloc_skb(size, GFP_KERNEL); +	if (skb == NULL) +		return -ENOMEM; + +	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); + +	skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM); + +	return nfc_data_exchange(dev, local->target_idx, skb, +					nfc_llcp_recv, local); +} + +int nfc_llcp_send_connect(struct nfc_llcp_sock *sock) +{ +	struct nfc_llcp_local *local; +	struct sk_buff *skb; +	u8 *service_name_tlv = NULL, service_name_tlv_length; +	int err; +	u16 size = 0; + +	pr_debug("Sending CONNECT\n"); + +	local = sock->local; +	if (local == NULL) +		return -ENODEV; + +	if (sock->service_name != NULL) { +		service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN, +					sock->service_name, +					sock->service_name_len, +					&service_name_tlv_length); +		size += service_name_tlv_length; +	} + +	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len); + +	skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size); +	if (skb == NULL) { +		err = -ENOMEM; +		goto error_tlv; +	} + +	if (service_name_tlv != NULL) +		skb = llcp_add_tlv(skb, service_name_tlv, +					service_name_tlv_length); + +	skb_queue_tail(&local->tx_queue, skb); + +	return 0; + +error_tlv: +	pr_err("error %d\n", err); + +	kfree(service_name_tlv); + +	return err; +} + +int nfc_llcp_send_cc(struct nfc_llcp_sock *sock) +{ +	struct nfc_llcp_local *local; +	struct sk_buff *skb; + +	pr_debug("Sending CC\n"); + +	local = sock->local; +	if (local == NULL) +		return -ENODEV; + +	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, 0); +	if (skb == NULL) +		return -ENOMEM; + +	skb_queue_tail(&local->tx_queue, skb); + +	return 0; +} + +int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason) +{ +	struct sk_buff *skb; +	struct nfc_dev *dev; +	u16 size = 1; /* Reason code */ + +	pr_debug("Sending DM reason 0x%x\n", reason); + +	if (local == NULL) +		return -ENODEV; + +	dev = local->dev; +	if (dev == NULL) +		return -ENODEV; + +	size += LLCP_HEADER_SIZE; +	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; + +	skb = alloc_skb(size, GFP_KERNEL); +	if (skb == NULL) +		return -ENOMEM; + +	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); + +	skb = llcp_add_header(skb, ssap, dsap, LLCP_PDU_DM); + +	memcpy(skb_put(skb, 1), &reason, 1); + +	skb_queue_head(&local->tx_queue, skb); + +	return 0; +} + +int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock) +{ +	struct sk_buff *skb; +	struct nfc_llcp_local *local; + +	pr_debug("Send DISC\n"); + +	local = sock->local; +	if (local == NULL) +		return -ENODEV; + +	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0); +	if (skb == NULL) +		return -ENOMEM; + +	skb_queue_head(&local->tx_queue, skb); + +	return 0; +}  |