llc_proc.c

Go to the documentation of this file.

/*
 * proc_llc.c - proc interface for LLC
 *
 * Copyright (c) 2001 by Jay Schulist <[email protected]>
 *       2002-2003 by Arnaldo Carvalho de Melo <[email protected]>
 *
 * This program can be redistributed or modified under the terms of the
 * GNU General Public License as published by the Free Software Foundation.
 * This program is distributed without any warranty or implied warranty
 * of merchantability or fitness for a particular purpose.
 *
 * See the GNU General Public License for more details.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/proc_fs.h>
#include <linux/errno.h>
#include <linux/seq_file.h>
#include <linux/export.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <net/llc.h>
#include <net/llc_c_ac.h>
#include <net/llc_c_ev.h>
#include <net/llc_c_st.h>
#include <net/llc_conn.h>

static void llc_ui_format_mac(struct seq_file *seq, u8 *addr)
{
    seq_printf(seq, "%pM", addr);
}

static struct sock *llc_get_sk_idx(loff_t pos)
{
    struct llc_sap *sap;
    struct sock *sk = NULL;
    int i;

    list_for_each_entry_rcu(sap, &llc_sap_list, node) {
        spin_lock_bh(&sap->sk_lock);
        for (i = 0; i < LLC_SK_LADDR_HASH_ENTRIES; i++) {
            struct hlist_nulls_head *head = &sap->sk_laddr_hash[i];
            struct hlist_nulls_node *node;

            sk_nulls_for_each(sk, node, head) {
                if (!pos)
                    goto found; /* keep the lock */
                --pos;
            }
        }
        spin_unlock_bh(&sap->sk_lock);
    }
    sk = NULL;
found:
    return sk;
}

static void *llc_seq_start(struct seq_file *seq, loff_t *pos)
{
    loff_t l = *pos;

    rcu_read_lock_bh();
    return l ? llc_get_sk_idx(--l) : SEQ_START_TOKEN;
}

static struct sock *laddr_hash_next(struct llc_sap *sap, int bucket)
{
    struct hlist_nulls_node *node;
    struct sock *sk = NULL;

    while (++bucket < LLC_SK_LADDR_HASH_ENTRIES)
        sk_nulls_for_each(sk, node, &sap->sk_laddr_hash[bucket])
            goto out;

out:
    return sk;
}

static void *llc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
    struct sock* sk, *next;
    struct llc_sock *llc;
    struct llc_sap *sap;

    ++*pos;
    if (v == SEQ_START_TOKEN) {
        sk = llc_get_sk_idx(0);
        goto out;
    }
    sk = v;
    next = sk_nulls_next(sk);
    if (next) {
        sk = next;
        goto out;
    }
    llc = llc_sk(sk);
    sap = llc->sap;
    sk = laddr_hash_next(sap, llc_sk_laddr_hashfn(sap, &llc->laddr));
    if (sk)
        goto out;
    spin_unlock_bh(&sap->sk_lock);
    list_for_each_entry_continue_rcu(sap, &llc_sap_list, node) {
        spin_lock_bh(&sap->sk_lock);
        sk = laddr_hash_next(sap, -1);
        if (sk)
            break; /* keep the lock */
        spin_unlock_bh(&sap->sk_lock);
    }
out:
    return sk;
}

static void llc_seq_stop(struct seq_file *seq, void *v)
{
    if (v && v != SEQ_START_TOKEN) {
        struct sock *sk = v;
        struct llc_sock *llc = llc_sk(sk);
        struct llc_sap *sap = llc->sap;

        spin_unlock_bh(&sap->sk_lock);
    }
    rcu_read_unlock_bh();
}

static int llc_seq_socket_show(struct seq_file *seq, void *v)
{
    struct sock* sk;
    struct llc_sock *llc;

    if (v == SEQ_START_TOKEN) {
        seq_puts(seq, "SKt Mc local_mac_sap        remote_mac_sap   "
                  "    tx_queue rx_queue st uid link\n");
        goto out;
    }
    sk = v;
    llc = llc_sk(sk);

    /* FIXME: check if the address is multicast */
    seq_printf(seq, "%2X  %2X ", sk->sk_type, 0);

    if (llc->dev)
        llc_ui_format_mac(seq, llc->dev->dev_addr);
    else {
        u8 addr[6] = {0,0,0,0,0,0};
        llc_ui_format_mac(seq, addr);
    }
    seq_printf(seq, "@%02X ", llc->sap->laddr.lsap);
    llc_ui_format_mac(seq, llc->daddr.mac);
    seq_printf(seq, "@%02X %8d %8d %2d %3d %4d\n", llc->daddr.lsap,
           sk_wmem_alloc_get(sk),
           sk_rmem_alloc_get(sk) - llc->copied_seq,
           sk->sk_state,
           from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
           llc->link);
out:
    return 0;
}

static const char *const llc_conn_state_names[] = {
    [LLC_CONN_STATE_ADM] =        "adm",
    [LLC_CONN_STATE_SETUP] =      "setup",
    [LLC_CONN_STATE_NORMAL] =     "normal",
    [LLC_CONN_STATE_BUSY] =       "busy",
    [LLC_CONN_STATE_REJ] =        "rej",
    [LLC_CONN_STATE_AWAIT] =      "await",
    [LLC_CONN_STATE_AWAIT_BUSY] = "await_busy",
    [LLC_CONN_STATE_AWAIT_REJ] =  "await_rej",
    [LLC_CONN_STATE_D_CONN] =     "d_conn",
    [LLC_CONN_STATE_RESET] =      "reset",
    [LLC_CONN_STATE_ERROR] =      "error",
    [LLC_CONN_STATE_TEMP] =       "temp",
};

static int llc_seq_core_show(struct seq_file *seq, void *v)
{
    struct sock* sk;
    struct llc_sock *llc;

    if (v == SEQ_START_TOKEN) {
        seq_puts(seq, "Connection list:\n"
                  "dsap state      retr txw rxw pf ff sf df rs cs "
                  "tack tpfc trs tbs blog busr\n");
        goto out;
    }
    sk = v;
    llc = llc_sk(sk);

    seq_printf(seq, " %02X  %-10s %3d  %3d %3d %2d %2d %2d %2d %2d %2d "
            "%4d %4d %3d %3d %4d %4d\n",
           llc->daddr.lsap, llc_conn_state_names[llc->state],
           llc->retry_count, llc->k, llc->rw, llc->p_flag, llc->f_flag,
           llc->s_flag, llc->data_flag, llc->remote_busy_flag,
           llc->cause_flag, timer_pending(&llc->ack_timer.timer),
           timer_pending(&llc->pf_cycle_timer.timer),
           timer_pending(&llc->rej_sent_timer.timer),
           timer_pending(&llc->busy_state_timer.timer),
           !!sk->sk_backlog.tail, !!sock_owned_by_user(sk));
out:
    return 0;
}

static const struct seq_operations llc_seq_socket_ops = {
    .start  = llc_seq_start,
    .next   = llc_seq_next,
    .stop   = llc_seq_stop,
    .show   = llc_seq_socket_show,
};

static const struct seq_operations llc_seq_core_ops = {
    .start  = llc_seq_start,
    .next   = llc_seq_next,
    .stop   = llc_seq_stop,
    .show   = llc_seq_core_show,
};

static int llc_seq_socket_open(struct inode *inode, struct file *file)
{
    return seq_open(file, &llc_seq_socket_ops);
}

static int llc_seq_core_open(struct inode *inode, struct file *file)
{
    return seq_open(file, &llc_seq_core_ops);
}

static const struct file_operations llc_seq_socket_fops = {
    .owner      = THIS_MODULE,
    .open       = llc_seq_socket_open,
    .read       = seq_read,
    .llseek     = seq_lseek,
    .release    = seq_release,
};

static const struct file_operations llc_seq_core_fops = {
    .owner      = THIS_MODULE,
    .open       = llc_seq_core_open,
    .read       = seq_read,
    .llseek     = seq_lseek,
    .release    = seq_release,
};

static struct proc_dir_entry *llc_proc_dir;

int __init llc_proc_init(void)
{
    int rc = -ENOMEM;
    struct proc_dir_entry *p;

    llc_proc_dir = proc_mkdir("llc", init_net.proc_net);
    if (!llc_proc_dir)
        goto out;

    p = proc_create("socket", S_IRUGO, llc_proc_dir, &llc_seq_socket_fops);
    if (!p)
        goto out_socket;

    p = proc_create("core", S_IRUGO, llc_proc_dir, &llc_seq_core_fops);
    if (!p)
        goto out_core;

    rc = 0;
out:
    return rc;
out_core:
    remove_proc_entry("socket", llc_proc_dir);
out_socket:
    remove_proc_entry("llc", init_net.proc_net);
    goto out;
}

void llc_proc_exit(void)
{
    remove_proc_entry("socket", llc_proc_dir);
    remove_proc_entry("core", llc_proc_dir);
    remove_proc_entry("llc", init_net.proc_net);
}