Free Electrons

Embedded Linux Experts

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
/*
 * Copyright (c) 2015, Sony Mobile Communications Inc.
 * Copyright (c) 2013, The Linux Foundation. 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 version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * 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.
 */
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/qrtr.h>
#include <linux/termios.h>	/* For TIOCINQ/OUTQ */

#include <net/sock.h>

#include "qrtr.h"

#define QRTR_PROTO_VER 1

/* auto-bind range */
#define QRTR_MIN_EPH_SOCKET 0x4000
#define QRTR_MAX_EPH_SOCKET 0x7fff

enum qrtr_pkt_type {
	QRTR_TYPE_DATA		= 1,
	QRTR_TYPE_HELLO		= 2,
	QRTR_TYPE_BYE		= 3,
	QRTR_TYPE_NEW_SERVER	= 4,
	QRTR_TYPE_DEL_SERVER	= 5,
	QRTR_TYPE_DEL_CLIENT	= 6,
	QRTR_TYPE_RESUME_TX	= 7,
	QRTR_TYPE_EXIT		= 8,
	QRTR_TYPE_PING		= 9,
};

/**
 * struct qrtr_hdr - (I|R)PCrouter packet header
 * @version: protocol version
 * @type: packet type; one of QRTR_TYPE_*
 * @src_node_id: source node
 * @src_port_id: source port
 * @confirm_rx: boolean; whether a resume-tx packet should be send in reply
 * @size: length of packet, excluding this header
 * @dst_node_id: destination node
 * @dst_port_id: destination port
 */
struct qrtr_hdr {
	__le32 version;
	__le32 type;
	__le32 src_node_id;
	__le32 src_port_id;
	__le32 confirm_rx;
	__le32 size;
	__le32 dst_node_id;
	__le32 dst_port_id;
} __packed;

#define QRTR_HDR_SIZE sizeof(struct qrtr_hdr)
#define QRTR_NODE_BCAST ((unsigned int)-1)
#define QRTR_PORT_CTRL ((unsigned int)-2)

struct qrtr_sock {
	/* WARNING: sk must be the first member */
	struct sock sk;
	struct sockaddr_qrtr us;
	struct sockaddr_qrtr peer;
};

static inline struct qrtr_sock *qrtr_sk(struct sock *sk)
{
	BUILD_BUG_ON(offsetof(struct qrtr_sock, sk) != 0);
	return container_of(sk, struct qrtr_sock, sk);
}

static unsigned int qrtr_local_nid = -1;

/* for node ids */
static RADIX_TREE(qrtr_nodes, GFP_KERNEL);
/* broadcast list */
static LIST_HEAD(qrtr_all_nodes);
/* lock for qrtr_nodes, qrtr_all_nodes and node reference */
static DEFINE_MUTEX(qrtr_node_lock);

/* local port allocation management */
static DEFINE_IDR(qrtr_ports);
static DEFINE_MUTEX(qrtr_port_lock);

/**
 * struct qrtr_node - endpoint node
 * @ep_lock: lock for endpoint management and callbacks
 * @ep: endpoint
 * @ref: reference count for node
 * @nid: node id
 * @rx_queue: receive queue
 * @work: scheduled work struct for recv work
 * @item: list item for broadcast list
 */
struct qrtr_node {
	struct mutex ep_lock;
	struct qrtr_endpoint *ep;
	struct kref ref;
	unsigned int nid;

	struct sk_buff_head rx_queue;
	struct work_struct work;
	struct list_head item;
};

/* Release node resources and free the node.
 *
 * Do not call directly, use qrtr_node_release.  To be used with
 * kref_put_mutex.  As such, the node mutex is expected to be locked on call.
 */
static void __qrtr_node_release(struct kref *kref)
{
	struct qrtr_node *node = container_of(kref, struct qrtr_node, ref);

	if (node->nid != QRTR_EP_NID_AUTO)
		radix_tree_delete(&qrtr_nodes, node->nid);

	list_del(&node->item);
	mutex_unlock(&qrtr_node_lock);

	skb_queue_purge(&node->rx_queue);
	kfree(node);
}

/* Increment reference to node. */
static struct qrtr_node *qrtr_node_acquire(struct qrtr_node *node)
{
	if (node)
		kref_get(&node->ref);
	return node;
}

/* Decrement reference to node and release as necessary. */
static void qrtr_node_release(struct qrtr_node *node)
{
	if (!node)
		return;
	kref_put_mutex(&node->ref, __qrtr_node_release, &qrtr_node_lock);
}

/* Pass an outgoing packet socket buffer to the endpoint driver. */
static int qrtr_node_enqueue(struct qrtr_node *node, struct sk_buff *skb)
{
	int rc = -ENODEV;

	mutex_lock(&node->ep_lock);
	if (node->ep)
		rc = node->ep->xmit(node->ep, skb);
	else
		kfree_skb(skb);
	mutex_unlock(&node->ep_lock);

	return rc;
}

/* Lookup node by id.
 *
 * callers must release with qrtr_node_release()
 */
static struct qrtr_node *qrtr_node_lookup(unsigned int nid)
{
	struct qrtr_node *node;

	mutex_lock(&qrtr_node_lock);
	node = radix_tree_lookup(&qrtr_nodes, nid);
	node = qrtr_node_acquire(node);
	mutex_unlock(&qrtr_node_lock);

	return node;
}

/* Assign node id to node.
 *
 * This is mostly useful for automatic node id assignment, based on
 * the source id in the incoming packet.
 */
static void qrtr_node_assign(struct qrtr_node *node, unsigned int nid)
{
	if (node->nid != QRTR_EP_NID_AUTO || nid == QRTR_EP_NID_AUTO)
		return;

	mutex_lock(&qrtr_node_lock);
	radix_tree_insert(&qrtr_nodes, nid, node);
	node->nid = nid;
	mutex_unlock(&qrtr_node_lock);
}

/**
 * qrtr_endpoint_post() - post incoming data
 * @ep: endpoint handle
 * @data: data pointer
 * @len: size of data in bytes
 *
 * Return: 0 on success; negative error code on failure
 */
int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len)
{
	struct qrtr_node *node = ep->node;
	const struct qrtr_hdr *phdr = data;
	struct sk_buff *skb;
	unsigned int psize;
	unsigned int size;
	unsigned int type;
	unsigned int ver;
	unsigned int dst;

	if (len < QRTR_HDR_SIZE || len & 3)
		return -EINVAL;

	ver = le32_to_cpu(phdr->version);
	size = le32_to_cpu(phdr->size);
	type = le32_to_cpu(phdr->type);
	dst = le32_to_cpu(phdr->dst_port_id);

	psize = (size + 3) & ~3;

	if (ver != QRTR_PROTO_VER)
		return -EINVAL;

	if (len != psize + QRTR_HDR_SIZE)
		return -EINVAL;

	if (dst != QRTR_PORT_CTRL && type != QRTR_TYPE_DATA)
		return -EINVAL;

	skb = netdev_alloc_skb(NULL, len);
	if (!skb)
		return -ENOMEM;

	skb_reset_transport_header(skb);
	memcpy(skb_put(skb, len), data, len);

	skb_queue_tail(&node->rx_queue, skb);
	schedule_work(&node->work);

	return 0;
}
EXPORT_SYMBOL_GPL(qrtr_endpoint_post);

/* Allocate and construct a resume-tx packet. */
static struct sk_buff *qrtr_alloc_resume_tx(u32 src_node,
					    u32 dst_node, u32 port)
{
	const int pkt_len = 20;
	struct qrtr_hdr *hdr;
	struct sk_buff *skb;
	u32 *buf;

	skb = alloc_skb(QRTR_HDR_SIZE + pkt_len, GFP_KERNEL);
	if (!skb)
		return NULL;
	skb_reset_transport_header(skb);

	hdr = (struct qrtr_hdr *)skb_put(skb, QRTR_HDR_SIZE);
	hdr->version = cpu_to_le32(QRTR_PROTO_VER);
	hdr->type = cpu_to_le32(QRTR_TYPE_RESUME_TX);
	hdr->src_node_id = cpu_to_le32(src_node);
	hdr->src_port_id = cpu_to_le32(QRTR_PORT_CTRL);
	hdr->confirm_rx = cpu_to_le32(0);
	hdr->size = cpu_to_le32(pkt_len);
	hdr->dst_node_id = cpu_to_le32(dst_node);
	hdr->dst_port_id = cpu_to_le32(QRTR_PORT_CTRL);

	buf = (u32 *)skb_put(skb, pkt_len);
	memset(buf, 0, pkt_len);
	buf[0] = cpu_to_le32(QRTR_TYPE_RESUME_TX);
	buf[1] = cpu_to_le32(src_node);
	buf[2] = cpu_to_le32(port);

	return skb;
}

static struct qrtr_sock *qrtr_port_lookup(int port);
static void qrtr_port_put(struct qrtr_sock *ipc);

/* Handle and route a received packet.
 *
 * This will auto-reply with resume-tx packet as necessary.
 */
static void qrtr_node_rx_work(struct work_struct *work)
{
	struct qrtr_node *node = container_of(work, struct qrtr_node, work);
	struct sk_buff *skb;

	while ((skb = skb_dequeue(&node->rx_queue)) != NULL) {
		const struct qrtr_hdr *phdr;
		u32 dst_node, dst_port;
		struct qrtr_sock *ipc;
		u32 src_node;
		int confirm;

		phdr = (const struct qrtr_hdr *)skb_transport_header(skb);
		src_node = le32_to_cpu(phdr->src_node_id);
		dst_node = le32_to_cpu(phdr->dst_node_id);
		dst_port = le32_to_cpu(phdr->dst_port_id);
		confirm = !!phdr->confirm_rx;

		qrtr_node_assign(node, src_node);

		ipc = qrtr_port_lookup(dst_port);
		if (!ipc) {
			kfree_skb(skb);
		} else {
			if (sock_queue_rcv_skb(&ipc->sk, skb))
				kfree_skb(skb);

			qrtr_port_put(ipc);
		}

		if (confirm) {
			skb = qrtr_alloc_resume_tx(dst_node, node->nid, dst_port);
			if (!skb)
				break;
			if (qrtr_node_enqueue(node, skb))
				break;
		}
	}
}

/**
 * qrtr_endpoint_register() - register a new endpoint
 * @ep: endpoint to register
 * @nid: desired node id; may be QRTR_EP_NID_AUTO for auto-assignment
 * Return: 0 on success; negative error code on failure
 *
 * The specified endpoint must have the xmit function pointer set on call.
 */
int qrtr_endpoint_register(struct qrtr_endpoint *ep, unsigned int nid)
{
	struct qrtr_node *node;

	if (!ep || !ep->xmit)
		return -EINVAL;

	node = kzalloc(sizeof(*node), GFP_KERNEL);
	if (!node)
		return -ENOMEM;

	INIT_WORK(&node->work, qrtr_node_rx_work);
	kref_init(&node->ref);
	mutex_init(&node->ep_lock);
	skb_queue_head_init(&node->rx_queue);
	node->nid = QRTR_EP_NID_AUTO;
	node->ep = ep;

	qrtr_node_assign(node, nid);

	mutex_lock(&qrtr_node_lock);
	list_add(&node->item, &qrtr_all_nodes);
	mutex_unlock(&qrtr_node_lock);
	ep->node = node;

	return 0;
}
EXPORT_SYMBOL_GPL(qrtr_endpoint_register);

/**
 * qrtr_endpoint_unregister - unregister endpoint
 * @ep: endpoint to unregister
 */
void qrtr_endpoint_unregister(struct qrtr_endpoint *ep)
{
	struct qrtr_node *node = ep->node;

	mutex_lock(&node->ep_lock);
	node->ep = NULL;
	mutex_unlock(&node->ep_lock);

	qrtr_node_release(node);
	ep->node = NULL;
}
EXPORT_SYMBOL_GPL(qrtr_endpoint_unregister);

/* Lookup socket by port.
 *
 * Callers must release with qrtr_port_put()
 */
static struct qrtr_sock *qrtr_port_lookup(int port)
{
	struct qrtr_sock *ipc;

	if (port == QRTR_PORT_CTRL)
		port = 0;

	mutex_lock(&qrtr_port_lock);
	ipc = idr_find(&qrtr_ports, port);
	if (ipc)
		sock_hold(&ipc->sk);
	mutex_unlock(&qrtr_port_lock);

	return ipc;
}

/* Release acquired socket. */
static void qrtr_port_put(struct qrtr_sock *ipc)
{
	sock_put(&ipc->sk);
}

/* Remove port assignment. */
static void qrtr_port_remove(struct qrtr_sock *ipc)
{
	int port = ipc->us.sq_port;

	if (port == QRTR_PORT_CTRL)
		port = 0;

	__sock_put(&ipc->sk);

	mutex_lock(&qrtr_port_lock);
	idr_remove(&qrtr_ports, port);
	mutex_unlock(&qrtr_port_lock);
}

/* Assign port number to socket.
 *
 * Specify port in the integer pointed to by port, and it will be adjusted
 * on return as necesssary.
 *
 * Port may be:
 *   0: Assign ephemeral port in [QRTR_MIN_EPH_SOCKET, QRTR_MAX_EPH_SOCKET]
 *   <QRTR_MIN_EPH_SOCKET: Specified; requires CAP_NET_ADMIN
 *   >QRTR_MIN_EPH_SOCKET: Specified; available to all
 */
static int qrtr_port_assign(struct qrtr_sock *ipc, int *port)
{
	int rc;

	mutex_lock(&qrtr_port_lock);
	if (!*port) {
		rc = idr_alloc(&qrtr_ports, ipc,
			       QRTR_MIN_EPH_SOCKET, QRTR_MAX_EPH_SOCKET + 1,
			       GFP_ATOMIC);
		if (rc >= 0)
			*port = rc;
	} else if (*port < QRTR_MIN_EPH_SOCKET && !capable(CAP_NET_ADMIN)) {
		rc = -EACCES;
	} else if (*port == QRTR_PORT_CTRL) {
		rc = idr_alloc(&qrtr_ports, ipc, 0, 1, GFP_ATOMIC);
	} else {
		rc = idr_alloc(&qrtr_ports, ipc, *port, *port + 1, GFP_ATOMIC);
		if (rc >= 0)
			*port = rc;
	}
	mutex_unlock(&qrtr_port_lock);

	if (rc == -ENOSPC)
		return -EADDRINUSE;
	else if (rc < 0)
		return rc;

	sock_hold(&ipc->sk);

	return 0;
}

/* Bind socket to address.
 *
 * Socket should be locked upon call.
 */
static int __qrtr_bind(struct socket *sock,
		       const struct sockaddr_qrtr *addr, int zapped)
{
	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
	struct sock *sk = sock->sk;
	int port;
	int rc;

	/* rebinding ok */
	if (!zapped && addr->sq_port == ipc->us.sq_port)
		return 0;

	port = addr->sq_port;
	rc = qrtr_port_assign(ipc, &port);
	if (rc)
		return rc;

	/* unbind previous, if any */
	if (!zapped)
		qrtr_port_remove(ipc);
	ipc->us.sq_port = port;

	sock_reset_flag(sk, SOCK_ZAPPED);

	return 0;
}

/* Auto bind to an ephemeral port. */
static int qrtr_autobind(struct socket *sock)
{
	struct sock *sk = sock->sk;
	struct sockaddr_qrtr addr;

	if (!sock_flag(sk, SOCK_ZAPPED))
		return 0;

	addr.sq_family = AF_QIPCRTR;
	addr.sq_node = qrtr_local_nid;
	addr.sq_port = 0;

	return __qrtr_bind(sock, &addr, 1);
}

/* Bind socket to specified sockaddr. */
static int qrtr_bind(struct socket *sock, struct sockaddr *saddr, int len)
{
	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, saddr);
	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
	struct sock *sk = sock->sk;
	int rc;

	if (len < sizeof(*addr) || addr->sq_family != AF_QIPCRTR)
		return -EINVAL;

	if (addr->sq_node != ipc->us.sq_node)
		return -EINVAL;

	lock_sock(sk);
	rc = __qrtr_bind(sock, addr, sock_flag(sk, SOCK_ZAPPED));
	release_sock(sk);

	return rc;
}

/* Queue packet to local peer socket. */
static int qrtr_local_enqueue(struct qrtr_node *node, struct sk_buff *skb)
{
	const struct qrtr_hdr *phdr;
	struct qrtr_sock *ipc;

	phdr = (const struct qrtr_hdr *)skb_transport_header(skb);

	ipc = qrtr_port_lookup(le32_to_cpu(phdr->dst_port_id));
	if (!ipc || &ipc->sk == skb->sk) { /* do not send to self */
		kfree_skb(skb);
		return -ENODEV;
	}

	if (sock_queue_rcv_skb(&ipc->sk, skb)) {
		qrtr_port_put(ipc);
		kfree_skb(skb);
		return -ENOSPC;
	}

	qrtr_port_put(ipc);

	return 0;
}

/* Queue packet for broadcast. */
static int qrtr_bcast_enqueue(struct qrtr_node *node, struct sk_buff *skb)
{
	struct sk_buff *skbn;

	mutex_lock(&qrtr_node_lock);
	list_for_each_entry(node, &qrtr_all_nodes, item) {
		skbn = skb_clone(skb, GFP_KERNEL);
		if (!skbn)
			break;
		skb_set_owner_w(skbn, skb->sk);
		qrtr_node_enqueue(node, skbn);
	}
	mutex_unlock(&qrtr_node_lock);

	qrtr_local_enqueue(node, skb);

	return 0;
}

static int qrtr_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
{
	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, msg->msg_name);
	int (*enqueue_fn)(struct qrtr_node *, struct sk_buff *);
	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
	struct sock *sk = sock->sk;
	struct qrtr_node *node;
	struct qrtr_hdr *hdr;
	struct sk_buff *skb;
	size_t plen;
	int rc;

	if (msg->msg_flags & ~(MSG_DONTWAIT))
		return -EINVAL;

	if (len > 65535)
		return -EMSGSIZE;

	lock_sock(sk);

	if (addr) {
		if (msg->msg_namelen < sizeof(*addr)) {
			release_sock(sk);
			return -EINVAL;
		}

		if (addr->sq_family != AF_QIPCRTR) {
			release_sock(sk);
			return -EINVAL;
		}

		rc = qrtr_autobind(sock);
		if (rc) {
			release_sock(sk);
			return rc;
		}
	} else if (sk->sk_state == TCP_ESTABLISHED) {
		addr = &ipc->peer;
	} else {
		release_sock(sk);
		return -ENOTCONN;
	}

	node = NULL;
	if (addr->sq_node == QRTR_NODE_BCAST) {
		enqueue_fn = qrtr_bcast_enqueue;
	} else if (addr->sq_node == ipc->us.sq_node) {
		enqueue_fn = qrtr_local_enqueue;
	} else {
		enqueue_fn = qrtr_node_enqueue;
		node = qrtr_node_lookup(addr->sq_node);
		if (!node) {
			release_sock(sk);
			return -ECONNRESET;
		}
	}

	plen = (len + 3) & ~3;
	skb = sock_alloc_send_skb(sk, plen + QRTR_HDR_SIZE,
				  msg->msg_flags & MSG_DONTWAIT, &rc);
	if (!skb)
		goto out_node;

	skb_reset_transport_header(skb);
	skb_put(skb, len + QRTR_HDR_SIZE);

	hdr = (struct qrtr_hdr *)skb_transport_header(skb);
	hdr->version = cpu_to_le32(QRTR_PROTO_VER);
	hdr->src_node_id = cpu_to_le32(ipc->us.sq_node);
	hdr->src_port_id = cpu_to_le32(ipc->us.sq_port);
	hdr->confirm_rx = cpu_to_le32(0);
	hdr->size = cpu_to_le32(len);
	hdr->dst_node_id = cpu_to_le32(addr->sq_node);
	hdr->dst_port_id = cpu_to_le32(addr->sq_port);

	rc = skb_copy_datagram_from_iter(skb, QRTR_HDR_SIZE,
					 &msg->msg_iter, len);
	if (rc) {
		kfree_skb(skb);
		goto out_node;
	}

	if (plen != len) {
		skb_pad(skb, plen - len);
		skb_put(skb, plen - len);
	}

	if (ipc->us.sq_port == QRTR_PORT_CTRL) {
		if (len < 4) {
			rc = -EINVAL;
			kfree_skb(skb);
			goto out_node;
		}

		/* control messages already require the type as 'command' */
		skb_copy_bits(skb, QRTR_HDR_SIZE, &hdr->type, 4);
	} else {
		hdr->type = cpu_to_le32(QRTR_TYPE_DATA);
	}

	rc = enqueue_fn(node, skb);
	if (rc >= 0)
		rc = len;

out_node:
	qrtr_node_release(node);
	release_sock(sk);

	return rc;
}

static int qrtr_recvmsg(struct socket *sock, struct msghdr *msg,
			size_t size, int flags)
{
	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, msg->msg_name);
	const struct qrtr_hdr *phdr;
	struct sock *sk = sock->sk;
	struct sk_buff *skb;
	int copied, rc;

	lock_sock(sk);

	if (sock_flag(sk, SOCK_ZAPPED)) {
		release_sock(sk);
		return -EADDRNOTAVAIL;
	}

	skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
				flags & MSG_DONTWAIT, &rc);
	if (!skb) {
		release_sock(sk);
		return rc;
	}

	phdr = (const struct qrtr_hdr *)skb_transport_header(skb);
	copied = le32_to_cpu(phdr->size);
	if (copied > size) {
		copied = size;
		msg->msg_flags |= MSG_TRUNC;
	}

	rc = skb_copy_datagram_msg(skb, QRTR_HDR_SIZE, msg, copied);
	if (rc < 0)
		goto out;
	rc = copied;

	if (addr) {
		addr->sq_family = AF_QIPCRTR;
		addr->sq_node = le32_to_cpu(phdr->src_node_id);
		addr->sq_port = le32_to_cpu(phdr->src_port_id);
		msg->msg_namelen = sizeof(*addr);
	}

out:
	skb_free_datagram(sk, skb);
	release_sock(sk);

	return rc;
}

static int qrtr_connect(struct socket *sock, struct sockaddr *saddr,
			int len, int flags)
{
	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, saddr);
	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
	struct sock *sk = sock->sk;
	int rc;

	if (len < sizeof(*addr) || addr->sq_family != AF_QIPCRTR)
		return -EINVAL;

	lock_sock(sk);

	sk->sk_state = TCP_CLOSE;
	sock->state = SS_UNCONNECTED;

	rc = qrtr_autobind(sock);
	if (rc) {
		release_sock(sk);
		return rc;
	}

	ipc->peer = *addr;
	sock->state = SS_CONNECTED;
	sk->sk_state = TCP_ESTABLISHED;

	release_sock(sk);

	return 0;
}

static int qrtr_getname(struct socket *sock, struct sockaddr *saddr,
			int *len, int peer)
{
	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
	struct sockaddr_qrtr qaddr;
	struct sock *sk = sock->sk;

	lock_sock(sk);
	if (peer) {
		if (sk->sk_state != TCP_ESTABLISHED) {
			release_sock(sk);
			return -ENOTCONN;
		}

		qaddr = ipc->peer;
	} else {
		qaddr = ipc->us;
	}
	release_sock(sk);

	*len = sizeof(qaddr);
	qaddr.sq_family = AF_QIPCRTR;

	memcpy(saddr, &qaddr, sizeof(qaddr));

	return 0;
}

static int qrtr_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
	struct sock *sk = sock->sk;
	struct sockaddr_qrtr *sq;
	struct sk_buff *skb;
	struct ifreq ifr;
	long len = 0;
	int rc = 0;

	lock_sock(sk);

	switch (cmd) {
	case TIOCOUTQ:
		len = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
		if (len < 0)
			len = 0;
		rc = put_user(len, (int __user *)argp);
		break;
	case TIOCINQ:
		skb = skb_peek(&sk->sk_receive_queue);
		if (skb)
			len = skb->len - QRTR_HDR_SIZE;
		rc = put_user(len, (int __user *)argp);
		break;
	case SIOCGIFADDR:
		if (copy_from_user(&ifr, argp, sizeof(ifr))) {
			rc = -EFAULT;
			break;
		}

		sq = (struct sockaddr_qrtr *)&ifr.ifr_addr;
		*sq = ipc->us;
		if (copy_to_user(argp, &ifr, sizeof(ifr))) {
			rc = -EFAULT;
			break;
		}
		break;
	case SIOCGSTAMP:
		rc = sock_get_timestamp(sk, argp);
		break;
	case SIOCADDRT:
	case SIOCDELRT:
	case SIOCSIFADDR:
	case SIOCGIFDSTADDR:
	case SIOCSIFDSTADDR:
	case SIOCGIFBRDADDR:
	case SIOCSIFBRDADDR:
	case SIOCGIFNETMASK:
	case SIOCSIFNETMASK:
		rc = -EINVAL;
		break;
	default:
		rc = -ENOIOCTLCMD;
		break;
	}

	release_sock(sk);

	return rc;
}

static int qrtr_release(struct socket *sock)
{
	struct sock *sk = sock->sk;
	struct qrtr_sock *ipc;

	if (!sk)
		return 0;

	lock_sock(sk);

	ipc = qrtr_sk(sk);
	sk->sk_shutdown = SHUTDOWN_MASK;
	if (!sock_flag(sk, SOCK_DEAD))
		sk->sk_state_change(sk);

	sock_set_flag(sk, SOCK_DEAD);
	sock->sk = NULL;

	if (!sock_flag(sk, SOCK_ZAPPED))
		qrtr_port_remove(ipc);

	skb_queue_purge(&sk->sk_receive_queue);

	release_sock(sk);
	sock_put(sk);

	return 0;
}

static const struct proto_ops qrtr_proto_ops = {
	.owner		= THIS_MODULE,
	.family		= AF_QIPCRTR,
	.bind		= qrtr_bind,
	.connect	= qrtr_connect,
	.socketpair	= sock_no_socketpair,
	.accept		= sock_no_accept,
	.listen		= sock_no_listen,
	.sendmsg	= qrtr_sendmsg,
	.recvmsg	= qrtr_recvmsg,
	.getname	= qrtr_getname,
	.ioctl		= qrtr_ioctl,
	.poll		= datagram_poll,
	.shutdown	= sock_no_shutdown,
	.setsockopt	= sock_no_setsockopt,
	.getsockopt	= sock_no_getsockopt,
	.release	= qrtr_release,
	.mmap		= sock_no_mmap,
	.sendpage	= sock_no_sendpage,
};

static struct proto qrtr_proto = {
	.name		= "QIPCRTR",
	.owner		= THIS_MODULE,
	.obj_size	= sizeof(struct qrtr_sock),
};

static int qrtr_create(struct net *net, struct socket *sock,
		       int protocol, int kern)
{
	struct qrtr_sock *ipc;
	struct sock *sk;

	if (sock->type != SOCK_DGRAM)
		return -EPROTOTYPE;

	sk = sk_alloc(net, AF_QIPCRTR, GFP_KERNEL, &qrtr_proto, kern);
	if (!sk)
		return -ENOMEM;

	sock_set_flag(sk, SOCK_ZAPPED);

	sock_init_data(sock, sk);
	sock->ops = &qrtr_proto_ops;

	ipc = qrtr_sk(sk);
	ipc->us.sq_family = AF_QIPCRTR;
	ipc->us.sq_node = qrtr_local_nid;
	ipc->us.sq_port = 0;

	return 0;
}

static const struct nla_policy qrtr_policy[IFA_MAX + 1] = {
	[IFA_LOCAL] = { .type = NLA_U32 },
};

static int qrtr_addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
{
	struct nlattr *tb[IFA_MAX + 1];
	struct ifaddrmsg *ifm;
	int rc;

	if (!netlink_capable(skb, CAP_NET_ADMIN))
		return -EPERM;

	if (!netlink_capable(skb, CAP_SYS_ADMIN))
		return -EPERM;

	ASSERT_RTNL();

	rc = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, qrtr_policy);
	if (rc < 0)
		return rc;

	ifm = nlmsg_data(nlh);
	if (!tb[IFA_LOCAL])
		return -EINVAL;

	qrtr_local_nid = nla_get_u32(tb[IFA_LOCAL]);
	return 0;
}

static const struct net_proto_family qrtr_family = {
	.owner	= THIS_MODULE,
	.family	= AF_QIPCRTR,
	.create	= qrtr_create,
};

static int __init qrtr_proto_init(void)
{
	int rc;

	rc = proto_register(&qrtr_proto, 1);
	if (rc)
		return rc;

	rc = sock_register(&qrtr_family);
	if (rc) {
		proto_unregister(&qrtr_proto);
		return rc;
	}

	rtnl_register(PF_QIPCRTR, RTM_NEWADDR, qrtr_addr_doit, NULL, NULL);

	return 0;
}
module_init(qrtr_proto_init);

static void __exit qrtr_proto_fini(void)
{
	rtnl_unregister(PF_QIPCRTR, RTM_NEWADDR);
	sock_unregister(qrtr_family.family);
	proto_unregister(&qrtr_proto);
}
module_exit(qrtr_proto_fini);

MODULE_DESCRIPTION("Qualcomm IPC-router driver");
MODULE_LICENSE("GPL v2");