11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * X.25 Packet Layer release 002 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * This is ALPHA test software. This code may break your machine, 51da177e4SLinus Torvalds * randomly fail to work with new releases, misbehave and/or generally 61da177e4SLinus Torvalds * screw up. It might even work. 71da177e4SLinus Torvalds * 81da177e4SLinus Torvalds * This code REQUIRES 2.1.15 or higher 91da177e4SLinus Torvalds * 101da177e4SLinus Torvalds * This module: 111da177e4SLinus Torvalds * This module is free software; you can redistribute it and/or 121da177e4SLinus Torvalds * modify it under the terms of the GNU General Public License 131da177e4SLinus Torvalds * as published by the Free Software Foundation; either version 141da177e4SLinus Torvalds * 2 of the License, or (at your option) any later version. 151da177e4SLinus Torvalds * 161da177e4SLinus Torvalds * History 171da177e4SLinus Torvalds * X.25 001 Jonathan Naylor Started coding. 181da177e4SLinus Torvalds * X.25 002 Jonathan Naylor Centralised disconnection code. 191da177e4SLinus Torvalds * New timer architecture. 201da177e4SLinus Torvalds * 2000-03-20 Daniela Squassoni Disabling/enabling of facilities 211da177e4SLinus Torvalds * negotiation. 221da177e4SLinus Torvalds * 2000-11-10 Henner Eisen Check and reset for out-of-sequence 231da177e4SLinus Torvalds * i-frames. 241da177e4SLinus Torvalds */ 251da177e4SLinus Torvalds 26b73e9e3cSwangweidong #define pr_fmt(fmt) "X25: " fmt 27b73e9e3cSwangweidong 285a0e3ad6STejun Heo #include <linux/slab.h> 291da177e4SLinus Torvalds #include <linux/errno.h> 301da177e4SLinus Torvalds #include <linux/kernel.h> 311da177e4SLinus Torvalds #include <linux/string.h> 321da177e4SLinus Torvalds #include <linux/skbuff.h> 331da177e4SLinus Torvalds #include <net/sock.h> 34c752f073SArnaldo Carvalho de Melo #include <net/tcp_states.h> 351da177e4SLinus Torvalds #include <net/x25.h> 361da177e4SLinus Torvalds 371da177e4SLinus Torvalds static int x25_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more) 381da177e4SLinus Torvalds { 391da177e4SLinus Torvalds struct sk_buff *skbo, *skbn = skb; 401da177e4SLinus Torvalds struct x25_sock *x25 = x25_sk(sk); 411da177e4SLinus Torvalds 421da177e4SLinus Torvalds if (more) { 431da177e4SLinus Torvalds x25->fraglen += skb->len; 441da177e4SLinus Torvalds skb_queue_tail(&x25->fragment_queue, skb); 451da177e4SLinus Torvalds skb_set_owner_r(skb, sk); 461da177e4SLinus Torvalds return 0; 471da177e4SLinus Torvalds } 481da177e4SLinus Torvalds 491da177e4SLinus Torvalds if (!more && x25->fraglen > 0) { /* End of fragment */ 501da177e4SLinus Torvalds int len = x25->fraglen + skb->len; 511da177e4SLinus Torvalds 521da177e4SLinus Torvalds if ((skbn = alloc_skb(len, GFP_ATOMIC)) == NULL){ 531da177e4SLinus Torvalds kfree_skb(skb); 541da177e4SLinus Torvalds return 1; 551da177e4SLinus Torvalds } 561da177e4SLinus Torvalds 571da177e4SLinus Torvalds skb_queue_tail(&x25->fragment_queue, skb); 581da177e4SLinus Torvalds 59badff6d0SArnaldo Carvalho de Melo skb_reset_transport_header(skbn); 601da177e4SLinus Torvalds 611da177e4SLinus Torvalds skbo = skb_dequeue(&x25->fragment_queue); 621a4e2d09SArnaldo Carvalho de Melo skb_copy_from_linear_data(skbo, skb_put(skbn, skbo->len), 631a4e2d09SArnaldo Carvalho de Melo skbo->len); 641da177e4SLinus Torvalds kfree_skb(skbo); 651da177e4SLinus Torvalds 661da177e4SLinus Torvalds while ((skbo = 671da177e4SLinus Torvalds skb_dequeue(&x25->fragment_queue)) != NULL) { 681da177e4SLinus Torvalds skb_pull(skbo, (x25->neighbour->extended) ? 691da177e4SLinus Torvalds X25_EXT_MIN_LEN : X25_STD_MIN_LEN); 701a4e2d09SArnaldo Carvalho de Melo skb_copy_from_linear_data(skbo, 711a4e2d09SArnaldo Carvalho de Melo skb_put(skbn, skbo->len), 721a4e2d09SArnaldo Carvalho de Melo skbo->len); 731da177e4SLinus Torvalds kfree_skb(skbo); 741da177e4SLinus Torvalds } 751da177e4SLinus Torvalds 761da177e4SLinus Torvalds x25->fraglen = 0; 771da177e4SLinus Torvalds } 781da177e4SLinus Torvalds 791da177e4SLinus Torvalds skb_set_owner_r(skbn, sk); 801da177e4SLinus Torvalds skb_queue_tail(&sk->sk_receive_queue, skbn); 811da177e4SLinus Torvalds if (!sock_flag(sk, SOCK_DEAD)) 821da177e4SLinus Torvalds sk->sk_data_ready(sk, skbn->len); 831da177e4SLinus Torvalds 841da177e4SLinus Torvalds return 0; 851da177e4SLinus Torvalds } 861da177e4SLinus Torvalds 871da177e4SLinus Torvalds /* 881da177e4SLinus Torvalds * State machine for state 1, Awaiting Call Accepted State. 891da177e4SLinus Torvalds * The handling of the timer(s) is in file x25_timer.c. 901da177e4SLinus Torvalds * Handling of state 0 and connection release is in af_x25.c. 911da177e4SLinus Torvalds */ 921da177e4SLinus Torvalds static int x25_state1_machine(struct sock *sk, struct sk_buff *skb, int frametype) 931da177e4SLinus Torvalds { 941da177e4SLinus Torvalds struct x25_address source_addr, dest_addr; 95f5eb917bSJohn Hughes int len; 9695c30430Sandrew hendry struct x25_sock *x25 = x25_sk(sk); 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds switch (frametype) { 991da177e4SLinus Torvalds case X25_CALL_ACCEPTED: { 1001da177e4SLinus Torvalds 1011da177e4SLinus Torvalds x25_stop_timer(sk); 1021da177e4SLinus Torvalds x25->condition = 0x00; 1031da177e4SLinus Torvalds x25->vs = 0; 1041da177e4SLinus Torvalds x25->va = 0; 1051da177e4SLinus Torvalds x25->vr = 0; 1061da177e4SLinus Torvalds x25->vl = 0; 1071da177e4SLinus Torvalds x25->state = X25_STATE_3; 1081da177e4SLinus Torvalds sk->sk_state = TCP_ESTABLISHED; 1091da177e4SLinus Torvalds /* 1101da177e4SLinus Torvalds * Parse the data in the frame. 1111da177e4SLinus Torvalds */ 112cb101ed2SMatthew Daley if (!pskb_may_pull(skb, X25_STD_MIN_LEN)) 113cb101ed2SMatthew Daley goto out_clear; 1141da177e4SLinus Torvalds skb_pull(skb, X25_STD_MIN_LEN); 115f5eb917bSJohn Hughes 116f5eb917bSJohn Hughes len = x25_parse_address_block(skb, &source_addr, 117f5eb917bSJohn Hughes &dest_addr); 118f5eb917bSJohn Hughes if (len > 0) 119f5eb917bSJohn Hughes skb_pull(skb, len); 12095c30430Sandrew hendry else if (len < 0) 12195c30430Sandrew hendry goto out_clear; 122f5eb917bSJohn Hughes 123f5eb917bSJohn Hughes len = x25_parse_facilities(skb, &x25->facilities, 124a64b7b93SShaun Pereira &x25->dte_facilities, 125f5eb917bSJohn Hughes &x25->vc_facil_mask); 126f5eb917bSJohn Hughes if (len > 0) 127f5eb917bSJohn Hughes skb_pull(skb, len); 12895c30430Sandrew hendry else if (len < 0) 12995c30430Sandrew hendry goto out_clear; 1301da177e4SLinus Torvalds /* 1311da177e4SLinus Torvalds * Copy any Call User Data. 1321da177e4SLinus Torvalds */ 133091bb8abSroel kluin if (skb->len > 0) { 134c7fd0d48SMatthew Daley if (skb->len > X25_MAX_CUD_LEN) 135c7fd0d48SMatthew Daley goto out_clear; 136c7fd0d48SMatthew Daley 137cb101ed2SMatthew Daley skb_copy_bits(skb, 0, x25->calluserdata.cuddata, 1381da177e4SLinus Torvalds skb->len); 1391da177e4SLinus Torvalds x25->calluserdata.cudlength = skb->len; 1401da177e4SLinus Torvalds } 1411da177e4SLinus Torvalds if (!sock_flag(sk, SOCK_DEAD)) 1421da177e4SLinus Torvalds sk->sk_state_change(sk); 1431da177e4SLinus Torvalds break; 1441da177e4SLinus Torvalds } 1451da177e4SLinus Torvalds case X25_CLEAR_REQUEST: 146cb101ed2SMatthew Daley if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) 147cb101ed2SMatthew Daley goto out_clear; 148cb101ed2SMatthew Daley 1491da177e4SLinus Torvalds x25_write_internal(sk, X25_CLEAR_CONFIRMATION); 1501da177e4SLinus Torvalds x25_disconnect(sk, ECONNREFUSED, skb->data[3], skb->data[4]); 1511da177e4SLinus Torvalds break; 1521da177e4SLinus Torvalds 1531da177e4SLinus Torvalds default: 1541da177e4SLinus Torvalds break; 1551da177e4SLinus Torvalds } 1561da177e4SLinus Torvalds 1571da177e4SLinus Torvalds return 0; 15895c30430Sandrew hendry 15995c30430Sandrew hendry out_clear: 16095c30430Sandrew hendry x25_write_internal(sk, X25_CLEAR_REQUEST); 16195c30430Sandrew hendry x25->state = X25_STATE_2; 16295c30430Sandrew hendry x25_start_t23timer(sk); 16395c30430Sandrew hendry return 0; 1641da177e4SLinus Torvalds } 1651da177e4SLinus Torvalds 1661da177e4SLinus Torvalds /* 1671da177e4SLinus Torvalds * State machine for state 2, Awaiting Clear Confirmation State. 1681da177e4SLinus Torvalds * The handling of the timer(s) is in file x25_timer.c 1691da177e4SLinus Torvalds * Handling of state 0 and connection release is in af_x25.c. 1701da177e4SLinus Torvalds */ 1711da177e4SLinus Torvalds static int x25_state2_machine(struct sock *sk, struct sk_buff *skb, int frametype) 1721da177e4SLinus Torvalds { 1731da177e4SLinus Torvalds switch (frametype) { 1741da177e4SLinus Torvalds 1751da177e4SLinus Torvalds case X25_CLEAR_REQUEST: 176cb101ed2SMatthew Daley if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) 177cb101ed2SMatthew Daley goto out_clear; 178cb101ed2SMatthew Daley 1791da177e4SLinus Torvalds x25_write_internal(sk, X25_CLEAR_CONFIRMATION); 1801da177e4SLinus Torvalds x25_disconnect(sk, 0, skb->data[3], skb->data[4]); 1811da177e4SLinus Torvalds break; 1821da177e4SLinus Torvalds 1831da177e4SLinus Torvalds case X25_CLEAR_CONFIRMATION: 1841da177e4SLinus Torvalds x25_disconnect(sk, 0, 0, 0); 1851da177e4SLinus Torvalds break; 1861da177e4SLinus Torvalds 1871da177e4SLinus Torvalds default: 1881da177e4SLinus Torvalds break; 1891da177e4SLinus Torvalds } 1901da177e4SLinus Torvalds 1911da177e4SLinus Torvalds return 0; 192cb101ed2SMatthew Daley 193cb101ed2SMatthew Daley out_clear: 194cb101ed2SMatthew Daley x25_write_internal(sk, X25_CLEAR_REQUEST); 195cb101ed2SMatthew Daley x25_start_t23timer(sk); 196cb101ed2SMatthew Daley return 0; 1971da177e4SLinus Torvalds } 1981da177e4SLinus Torvalds 1991da177e4SLinus Torvalds /* 2001da177e4SLinus Torvalds * State machine for state 3, Connected State. 2011da177e4SLinus Torvalds * The handling of the timer(s) is in file x25_timer.c 2021da177e4SLinus Torvalds * Handling of state 0 and connection release is in af_x25.c. 2031da177e4SLinus Torvalds */ 2041da177e4SLinus Torvalds static int x25_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype, int ns, int nr, int q, int d, int m) 2051da177e4SLinus Torvalds { 2061da177e4SLinus Torvalds int queued = 0; 2071da177e4SLinus Torvalds int modulus; 2081da177e4SLinus Torvalds struct x25_sock *x25 = x25_sk(sk); 2091da177e4SLinus Torvalds 2101da177e4SLinus Torvalds modulus = (x25->neighbour->extended) ? X25_EMODULUS : X25_SMODULUS; 2111da177e4SLinus Torvalds 2121da177e4SLinus Torvalds switch (frametype) { 2131da177e4SLinus Torvalds 2141da177e4SLinus Torvalds case X25_RESET_REQUEST: 2151da177e4SLinus Torvalds x25_write_internal(sk, X25_RESET_CONFIRMATION); 2161da177e4SLinus Torvalds x25_stop_timer(sk); 2171da177e4SLinus Torvalds x25->condition = 0x00; 2181da177e4SLinus Torvalds x25->vs = 0; 2191da177e4SLinus Torvalds x25->vr = 0; 2201da177e4SLinus Torvalds x25->va = 0; 2211da177e4SLinus Torvalds x25->vl = 0; 2221da177e4SLinus Torvalds x25_requeue_frames(sk); 2231da177e4SLinus Torvalds break; 2241da177e4SLinus Torvalds 2251da177e4SLinus Torvalds case X25_CLEAR_REQUEST: 226cb101ed2SMatthew Daley if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) 227cb101ed2SMatthew Daley goto out_clear; 228cb101ed2SMatthew Daley 2291da177e4SLinus Torvalds x25_write_internal(sk, X25_CLEAR_CONFIRMATION); 2301da177e4SLinus Torvalds x25_disconnect(sk, 0, skb->data[3], skb->data[4]); 2311da177e4SLinus Torvalds break; 2321da177e4SLinus Torvalds 2331da177e4SLinus Torvalds case X25_RR: 2341da177e4SLinus Torvalds case X25_RNR: 2351da177e4SLinus Torvalds if (!x25_validate_nr(sk, nr)) { 2361da177e4SLinus Torvalds x25_clear_queues(sk); 2371da177e4SLinus Torvalds x25_write_internal(sk, X25_RESET_REQUEST); 2381da177e4SLinus Torvalds x25_start_t22timer(sk); 2391da177e4SLinus Torvalds x25->condition = 0x00; 2401da177e4SLinus Torvalds x25->vs = 0; 2411da177e4SLinus Torvalds x25->vr = 0; 2421da177e4SLinus Torvalds x25->va = 0; 2431da177e4SLinus Torvalds x25->vl = 0; 2441da177e4SLinus Torvalds x25->state = X25_STATE_4; 2451da177e4SLinus Torvalds } else { 2461da177e4SLinus Torvalds x25_frames_acked(sk, nr); 2471da177e4SLinus Torvalds if (frametype == X25_RNR) { 2481da177e4SLinus Torvalds x25->condition |= X25_COND_PEER_RX_BUSY; 2491da177e4SLinus Torvalds } else { 2501da177e4SLinus Torvalds x25->condition &= ~X25_COND_PEER_RX_BUSY; 2511da177e4SLinus Torvalds } 2521da177e4SLinus Torvalds } 2531da177e4SLinus Torvalds break; 2541da177e4SLinus Torvalds 2551da177e4SLinus Torvalds case X25_DATA: /* XXX */ 2561da177e4SLinus Torvalds x25->condition &= ~X25_COND_PEER_RX_BUSY; 2571da177e4SLinus Torvalds if ((ns != x25->vr) || !x25_validate_nr(sk, nr)) { 2581da177e4SLinus Torvalds x25_clear_queues(sk); 2591da177e4SLinus Torvalds x25_write_internal(sk, X25_RESET_REQUEST); 2601da177e4SLinus Torvalds x25_start_t22timer(sk); 2611da177e4SLinus Torvalds x25->condition = 0x00; 2621da177e4SLinus Torvalds x25->vs = 0; 2631da177e4SLinus Torvalds x25->vr = 0; 2641da177e4SLinus Torvalds x25->va = 0; 2651da177e4SLinus Torvalds x25->vl = 0; 2661da177e4SLinus Torvalds x25->state = X25_STATE_4; 2671da177e4SLinus Torvalds break; 2681da177e4SLinus Torvalds } 2691da177e4SLinus Torvalds x25_frames_acked(sk, nr); 2701da177e4SLinus Torvalds if (ns == x25->vr) { 2711da177e4SLinus Torvalds if (x25_queue_rx_frame(sk, skb, m) == 0) { 2721da177e4SLinus Torvalds x25->vr = (x25->vr + 1) % modulus; 2731da177e4SLinus Torvalds queued = 1; 2741da177e4SLinus Torvalds } else { 2751da177e4SLinus Torvalds /* Should never happen */ 2761da177e4SLinus Torvalds x25_clear_queues(sk); 2771da177e4SLinus Torvalds x25_write_internal(sk, X25_RESET_REQUEST); 2781da177e4SLinus Torvalds x25_start_t22timer(sk); 2791da177e4SLinus Torvalds x25->condition = 0x00; 2801da177e4SLinus Torvalds x25->vs = 0; 2811da177e4SLinus Torvalds x25->vr = 0; 2821da177e4SLinus Torvalds x25->va = 0; 2831da177e4SLinus Torvalds x25->vl = 0; 2841da177e4SLinus Torvalds x25->state = X25_STATE_4; 2851da177e4SLinus Torvalds break; 2861da177e4SLinus Torvalds } 2871da177e4SLinus Torvalds if (atomic_read(&sk->sk_rmem_alloc) > 2886bf1574eSEric Dumazet (sk->sk_rcvbuf >> 1)) 2891da177e4SLinus Torvalds x25->condition |= X25_COND_OWN_RX_BUSY; 2901da177e4SLinus Torvalds } 2911da177e4SLinus Torvalds /* 2921da177e4SLinus Torvalds * If the window is full Ack it immediately, else 2931da177e4SLinus Torvalds * start the holdback timer. 2941da177e4SLinus Torvalds */ 2951da177e4SLinus Torvalds if (((x25->vl + x25->facilities.winsize_in) % modulus) == x25->vr) { 2961da177e4SLinus Torvalds x25->condition &= ~X25_COND_ACK_PENDING; 2971da177e4SLinus Torvalds x25_stop_timer(sk); 2981da177e4SLinus Torvalds x25_enquiry_response(sk); 2991da177e4SLinus Torvalds } else { 3001da177e4SLinus Torvalds x25->condition |= X25_COND_ACK_PENDING; 3011da177e4SLinus Torvalds x25_start_t2timer(sk); 3021da177e4SLinus Torvalds } 3031da177e4SLinus Torvalds break; 3041da177e4SLinus Torvalds 3051da177e4SLinus Torvalds case X25_INTERRUPT_CONFIRMATION: 306b7792e34Sandrew hendry clear_bit(X25_INTERRUPT_FLAG, &x25->flags); 3071da177e4SLinus Torvalds break; 3081da177e4SLinus Torvalds 3091da177e4SLinus Torvalds case X25_INTERRUPT: 3101da177e4SLinus Torvalds if (sock_flag(sk, SOCK_URGINLINE)) 3111da177e4SLinus Torvalds queued = !sock_queue_rcv_skb(sk, skb); 3121da177e4SLinus Torvalds else { 3131da177e4SLinus Torvalds skb_set_owner_r(skb, sk); 3141da177e4SLinus Torvalds skb_queue_tail(&x25->interrupt_in_queue, skb); 3151da177e4SLinus Torvalds queued = 1; 3161da177e4SLinus Torvalds } 3171da177e4SLinus Torvalds sk_send_sigurg(sk); 3181da177e4SLinus Torvalds x25_write_internal(sk, X25_INTERRUPT_CONFIRMATION); 3191da177e4SLinus Torvalds break; 3201da177e4SLinus Torvalds 3211da177e4SLinus Torvalds default: 322b73e9e3cSwangweidong pr_warn("unknown %02X in state 3\n", frametype); 3231da177e4SLinus Torvalds break; 3241da177e4SLinus Torvalds } 3251da177e4SLinus Torvalds 3261da177e4SLinus Torvalds return queued; 327cb101ed2SMatthew Daley 328cb101ed2SMatthew Daley out_clear: 329cb101ed2SMatthew Daley x25_write_internal(sk, X25_CLEAR_REQUEST); 330cb101ed2SMatthew Daley x25->state = X25_STATE_2; 331cb101ed2SMatthew Daley x25_start_t23timer(sk); 332cb101ed2SMatthew Daley return 0; 3331da177e4SLinus Torvalds } 3341da177e4SLinus Torvalds 3351da177e4SLinus Torvalds /* 3361da177e4SLinus Torvalds * State machine for state 4, Awaiting Reset Confirmation State. 3371da177e4SLinus Torvalds * The handling of the timer(s) is in file x25_timer.c 3381da177e4SLinus Torvalds * Handling of state 0 and connection release is in af_x25.c. 3391da177e4SLinus Torvalds */ 3401da177e4SLinus Torvalds static int x25_state4_machine(struct sock *sk, struct sk_buff *skb, int frametype) 3411da177e4SLinus Torvalds { 342cb101ed2SMatthew Daley struct x25_sock *x25 = x25_sk(sk); 343cb101ed2SMatthew Daley 3441da177e4SLinus Torvalds switch (frametype) { 3451da177e4SLinus Torvalds 3461da177e4SLinus Torvalds case X25_RESET_REQUEST: 3471da177e4SLinus Torvalds x25_write_internal(sk, X25_RESET_CONFIRMATION); 3481da177e4SLinus Torvalds case X25_RESET_CONFIRMATION: { 3491da177e4SLinus Torvalds x25_stop_timer(sk); 3501da177e4SLinus Torvalds x25->condition = 0x00; 3511da177e4SLinus Torvalds x25->va = 0; 3521da177e4SLinus Torvalds x25->vr = 0; 3531da177e4SLinus Torvalds x25->vs = 0; 3541da177e4SLinus Torvalds x25->vl = 0; 3551da177e4SLinus Torvalds x25->state = X25_STATE_3; 3561da177e4SLinus Torvalds x25_requeue_frames(sk); 3571da177e4SLinus Torvalds break; 3581da177e4SLinus Torvalds } 3591da177e4SLinus Torvalds case X25_CLEAR_REQUEST: 360cb101ed2SMatthew Daley if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) 361cb101ed2SMatthew Daley goto out_clear; 362cb101ed2SMatthew Daley 3631da177e4SLinus Torvalds x25_write_internal(sk, X25_CLEAR_CONFIRMATION); 3641da177e4SLinus Torvalds x25_disconnect(sk, 0, skb->data[3], skb->data[4]); 3651da177e4SLinus Torvalds break; 3661da177e4SLinus Torvalds 3671da177e4SLinus Torvalds default: 3681da177e4SLinus Torvalds break; 3691da177e4SLinus Torvalds } 3701da177e4SLinus Torvalds 3711da177e4SLinus Torvalds return 0; 372cb101ed2SMatthew Daley 373cb101ed2SMatthew Daley out_clear: 374cb101ed2SMatthew Daley x25_write_internal(sk, X25_CLEAR_REQUEST); 375cb101ed2SMatthew Daley x25->state = X25_STATE_2; 376cb101ed2SMatthew Daley x25_start_t23timer(sk); 377cb101ed2SMatthew Daley return 0; 3781da177e4SLinus Torvalds } 3791da177e4SLinus Torvalds 3801da177e4SLinus Torvalds /* Higher level upcall for a LAPB frame */ 3811da177e4SLinus Torvalds int x25_process_rx_frame(struct sock *sk, struct sk_buff *skb) 3821da177e4SLinus Torvalds { 3831da177e4SLinus Torvalds struct x25_sock *x25 = x25_sk(sk); 3841da177e4SLinus Torvalds int queued = 0, frametype, ns, nr, q, d, m; 3851da177e4SLinus Torvalds 3861da177e4SLinus Torvalds if (x25->state == X25_STATE_0) 3871da177e4SLinus Torvalds return 0; 3881da177e4SLinus Torvalds 3891da177e4SLinus Torvalds frametype = x25_decode(sk, skb, &ns, &nr, &q, &d, &m); 3901da177e4SLinus Torvalds 3911da177e4SLinus Torvalds switch (x25->state) { 3921da177e4SLinus Torvalds case X25_STATE_1: 3931da177e4SLinus Torvalds queued = x25_state1_machine(sk, skb, frametype); 3941da177e4SLinus Torvalds break; 3951da177e4SLinus Torvalds case X25_STATE_2: 3961da177e4SLinus Torvalds queued = x25_state2_machine(sk, skb, frametype); 3971da177e4SLinus Torvalds break; 3981da177e4SLinus Torvalds case X25_STATE_3: 3991da177e4SLinus Torvalds queued = x25_state3_machine(sk, skb, frametype, ns, nr, q, d, m); 4001da177e4SLinus Torvalds break; 4011da177e4SLinus Torvalds case X25_STATE_4: 4021da177e4SLinus Torvalds queued = x25_state4_machine(sk, skb, frametype); 4031da177e4SLinus Torvalds break; 4041da177e4SLinus Torvalds } 4051da177e4SLinus Torvalds 4061da177e4SLinus Torvalds x25_kick(sk); 4071da177e4SLinus Torvalds 4081da177e4SLinus Torvalds return queued; 4091da177e4SLinus Torvalds } 4101da177e4SLinus Torvalds 4111da177e4SLinus Torvalds int x25_backlog_rcv(struct sock *sk, struct sk_buff *skb) 4121da177e4SLinus Torvalds { 4131da177e4SLinus Torvalds int queued = x25_process_rx_frame(sk, skb); 4141da177e4SLinus Torvalds 4151da177e4SLinus Torvalds if (!queued) 4161da177e4SLinus Torvalds kfree_skb(skb); 4171da177e4SLinus Torvalds 4181da177e4SLinus Torvalds return 0; 4191da177e4SLinus Torvalds } 420