| /* |
| * |
| * Generic Bluetooth HCI UART driver |
| * |
| * Copyright (C) 2015-2018 Intel Corporation |
| * |
| * |
| * 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 |
| * |
| */ |
| |
| #include <asm/unaligned.h> |
| |
| struct h4_recv_pkt { |
| u8 type; /* Packet type */ |
| u8 hlen; /* Header length */ |
| u8 loff; /* Data length offset in header */ |
| u8 lsize; /* Data length field size */ |
| u16 maxlen; /* Max overall packet length */ |
| int (*recv)(struct hci_dev *hdev, struct sk_buff *skb); |
| }; |
| |
| #define H4_RECV_ACL \ |
| .type = HCI_ACLDATA_PKT, \ |
| .hlen = HCI_ACL_HDR_SIZE, \ |
| .loff = 2, \ |
| .lsize = 2, \ |
| .maxlen = HCI_MAX_FRAME_SIZE \ |
| |
| #define H4_RECV_SCO \ |
| .type = HCI_SCODATA_PKT, \ |
| .hlen = HCI_SCO_HDR_SIZE, \ |
| .loff = 2, \ |
| .lsize = 1, \ |
| .maxlen = HCI_MAX_SCO_SIZE |
| |
| #define H4_RECV_EVENT \ |
| .type = HCI_EVENT_PKT, \ |
| .hlen = HCI_EVENT_HDR_SIZE, \ |
| .loff = 1, \ |
| .lsize = 1, \ |
| .maxlen = HCI_MAX_EVENT_SIZE |
| |
| static inline struct sk_buff *h4_recv_buf(struct hci_dev *hdev, |
| struct sk_buff *skb, |
| const unsigned char *buffer, |
| int count, |
| const struct h4_recv_pkt *pkts, |
| int pkts_count) |
| { |
| /* Check for error from previous call */ |
| if (IS_ERR(skb)) |
| skb = NULL; |
| |
| while (count) { |
| int i, len; |
| |
| if (!skb) { |
| for (i = 0; i < pkts_count; i++) { |
| if (buffer[0] != (&pkts[i])->type) |
| continue; |
| |
| skb = bt_skb_alloc((&pkts[i])->maxlen, |
| GFP_ATOMIC); |
| if (!skb) |
| return ERR_PTR(-ENOMEM); |
| |
| hci_skb_pkt_type(skb) = (&pkts[i])->type; |
| hci_skb_expect(skb) = (&pkts[i])->hlen; |
| break; |
| } |
| |
| /* Check for invalid packet type */ |
| if (!skb) |
| return ERR_PTR(-EILSEQ); |
| |
| count -= 1; |
| buffer += 1; |
| } |
| |
| len = min_t(uint, hci_skb_expect(skb) - skb->len, count); |
| skb_put_data(skb, buffer, len); |
| |
| count -= len; |
| buffer += len; |
| |
| /* Check for partial packet */ |
| if (skb->len < hci_skb_expect(skb)) |
| continue; |
| |
| for (i = 0; i < pkts_count; i++) { |
| if (hci_skb_pkt_type(skb) == (&pkts[i])->type) |
| break; |
| } |
| |
| if (i >= pkts_count) { |
| kfree_skb(skb); |
| return ERR_PTR(-EILSEQ); |
| } |
| |
| if (skb->len == (&pkts[i])->hlen) { |
| u16 dlen; |
| |
| switch ((&pkts[i])->lsize) { |
| case 0: |
| /* No variable data length */ |
| dlen = 0; |
| break; |
| case 1: |
| /* Single octet variable length */ |
| dlen = skb->data[(&pkts[i])->loff]; |
| hci_skb_expect(skb) += dlen; |
| |
| if (skb_tailroom(skb) < dlen) { |
| kfree_skb(skb); |
| return ERR_PTR(-EMSGSIZE); |
| } |
| break; |
| case 2: |
| /* Double octet variable length */ |
| dlen = get_unaligned_le16(skb->data + |
| (&pkts[i])->loff); |
| hci_skb_expect(skb) += dlen; |
| |
| if (skb_tailroom(skb) < dlen) { |
| kfree_skb(skb); |
| return ERR_PTR(-EMSGSIZE); |
| } |
| break; |
| default: |
| /* Unsupported variable length */ |
| kfree_skb(skb); |
| return ERR_PTR(-EILSEQ); |
| } |
| |
| if (!dlen) { |
| /* No more data, complete frame */ |
| (&pkts[i])->recv(hdev, skb); |
| skb = NULL; |
| } |
| } else { |
| /* Complete frame */ |
| (&pkts[i])->recv(hdev, skb); |
| skb = NULL; |
| } |
| } |
| |
| return skb; |
| } |