^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * PPP async serial channel driver for Linux.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright 1999 Paul Mackerras.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * This driver provides the encapsulation and framing for sending
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * and receiving PPP frames over async serial lines. It relies on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * the generic PPP layer to give it frames to send and to process
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * received frames. It implements the PPP line discipline.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * Part of the code in this driver was inspired by the old async-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * PPP driver, written by Michael Callahan and Al Longyear, and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * subsequently hacked by Paul Mackerras.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/skbuff.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/tty.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/netdevice.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include <linux/poll.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <linux/crc-ccitt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <linux/ppp_defs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include <linux/ppp-ioctl.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #include <linux/ppp_channel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #include <linux/spinlock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) #include <linux/interrupt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) #include <linux/jiffies.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) #include <asm/unaligned.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #include <asm/string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) #define PPP_VERSION "2.4.2"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) #define OBUFSIZE 4096
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) /* Structure for storing local state. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) struct asyncppp {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) struct tty_struct *tty;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) unsigned int flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) unsigned int state;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) unsigned int rbits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) int mru;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) spinlock_t xmit_lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) spinlock_t recv_lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) unsigned long xmit_flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) u32 xaccm[8];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) u32 raccm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) unsigned int bytes_sent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) unsigned int bytes_rcvd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) struct sk_buff *tpkt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) int tpkt_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) u16 tfcs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) unsigned char *optr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) unsigned char *olim;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) unsigned long last_xmit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) struct sk_buff *rpkt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) int lcp_fcs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) struct sk_buff_head rqueue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) struct tasklet_struct tsk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) refcount_t refcnt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) struct completion dead;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) struct ppp_channel chan; /* interface to generic ppp layer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) unsigned char obuf[OBUFSIZE];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) /* Bit numbers in xmit_flags */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) #define XMIT_WAKEUP 0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) #define XMIT_FULL 1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) #define XMIT_BUSY 2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) /* State bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) #define SC_TOSS 1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) #define SC_ESCAPE 2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) #define SC_PREV_ERROR 4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) /* Bits in rbits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) #define SC_RCV_BITS (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) static int flag_time = HZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) module_param(flag_time, int, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) MODULE_PARM_DESC(flag_time, "ppp_async: interval between flagged packets (in clock ticks)");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) MODULE_ALIAS_LDISC(N_PPP);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) * Prototypes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) static int ppp_async_encode(struct asyncppp *ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) static int ppp_async_send(struct ppp_channel *chan, struct sk_buff *skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) static int ppp_async_push(struct asyncppp *ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) static void ppp_async_flush_output(struct asyncppp *ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) static void ppp_async_input(struct asyncppp *ap, const unsigned char *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) char *flags, int count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) static int ppp_async_ioctl(struct ppp_channel *chan, unsigned int cmd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) unsigned long arg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) static void ppp_async_process(unsigned long arg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) static void async_lcp_peek(struct asyncppp *ap, unsigned char *data,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) int len, int inbound);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) static const struct ppp_channel_ops async_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) .start_xmit = ppp_async_send,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) .ioctl = ppp_async_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) * Routines implementing the PPP line discipline.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) * We have a potential race on dereferencing tty->disc_data,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) * because the tty layer provides no locking at all - thus one
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) * cpu could be running ppp_asynctty_receive while another
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * calls ppp_asynctty_close, which zeroes tty->disc_data and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) * frees the memory that ppp_asynctty_receive is using. The best
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) * way to fix this is to use a rwlock in the tty struct, but for now
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) * we use a single global rwlock for all ttys in ppp line discipline.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) * FIXME: this is no longer true. The _close path for the ldisc is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) * now guaranteed to be sane.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) static DEFINE_RWLOCK(disc_data_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) static struct asyncppp *ap_get(struct tty_struct *tty)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) struct asyncppp *ap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) read_lock(&disc_data_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) ap = tty->disc_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) if (ap != NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) refcount_inc(&ap->refcnt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) read_unlock(&disc_data_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) return ap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) static void ap_put(struct asyncppp *ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) if (refcount_dec_and_test(&ap->refcnt))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) complete(&ap->dead);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) * Called when a tty is put into PPP line discipline. Called in process
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) * context.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) static int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) ppp_asynctty_open(struct tty_struct *tty)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) struct asyncppp *ap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) int speed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) if (tty->ops->write == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) return -EOPNOTSUPP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) err = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) ap = kzalloc(sizeof(*ap), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) if (!ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) /* initialize the asyncppp structure */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) ap->tty = tty;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) ap->mru = PPP_MRU;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) spin_lock_init(&ap->xmit_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) spin_lock_init(&ap->recv_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) ap->xaccm[0] = ~0U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) ap->xaccm[3] = 0x60000000U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) ap->raccm = ~0U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) ap->optr = ap->obuf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) ap->olim = ap->obuf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) ap->lcp_fcs = -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) skb_queue_head_init(&ap->rqueue);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) tasklet_init(&ap->tsk, ppp_async_process, (unsigned long) ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) refcount_set(&ap->refcnt, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) init_completion(&ap->dead);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) ap->chan.private = ap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) ap->chan.ops = &async_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) ap->chan.mtu = PPP_MRU;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) speed = tty_get_baud_rate(tty);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) ap->chan.speed = speed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) err = ppp_register_channel(&ap->chan);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) goto out_free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) tty->disc_data = ap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) tty->receive_room = 65536;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) out_free:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) kfree(ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) * Called when the tty is put into another line discipline
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) * or it hangs up. We have to wait for any cpu currently
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) * executing in any of the other ppp_asynctty_* routines to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) * finish before we can call ppp_unregister_channel and free
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) * the asyncppp struct. This routine must be called from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) * process context, not interrupt or softirq context.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) static void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) ppp_asynctty_close(struct tty_struct *tty)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) struct asyncppp *ap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) write_lock_irq(&disc_data_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) ap = tty->disc_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) tty->disc_data = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) write_unlock_irq(&disc_data_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) if (!ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) * We have now ensured that nobody can start using ap from now
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) * on, but we have to wait for all existing users to finish.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) * Note that ppp_unregister_channel ensures that no calls to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) * our channel ops (i.e. ppp_async_send/ioctl) are in progress
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) * by the time it returns.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) if (!refcount_dec_and_test(&ap->refcnt))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) wait_for_completion(&ap->dead);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) tasklet_kill(&ap->tsk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) ppp_unregister_channel(&ap->chan);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) kfree_skb(ap->rpkt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) skb_queue_purge(&ap->rqueue);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) kfree_skb(ap->tpkt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) kfree(ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) * Called on tty hangup in process context.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) * Wait for I/O to driver to complete and unregister PPP channel.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) * This is already done by the close routine, so just call that.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) static int ppp_asynctty_hangup(struct tty_struct *tty)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) ppp_asynctty_close(tty);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) * Read does nothing - no data is ever available this way.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) * Pppd reads and writes packets via /dev/ppp instead.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) static ssize_t
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) ppp_asynctty_read(struct tty_struct *tty, struct file *file,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) unsigned char *buf, size_t count,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) void **cookie, unsigned long offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) return -EAGAIN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) * Write on the tty does nothing, the packets all come in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) * from the ppp generic stuff.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) static ssize_t
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) ppp_asynctty_write(struct tty_struct *tty, struct file *file,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) const unsigned char *buf, size_t count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) return -EAGAIN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) * Called in process context only. May be re-entered by multiple
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) * ioctl calling threads.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) static int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) ppp_asynctty_ioctl(struct tty_struct *tty, struct file *file,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) unsigned int cmd, unsigned long arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) struct asyncppp *ap = ap_get(tty);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) int err, val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) int __user *p = (int __user *)arg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) if (!ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) return -ENXIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) err = -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) switch (cmd) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) case PPPIOCGCHAN:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) err = -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) if (put_user(ppp_channel_index(&ap->chan), p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) case PPPIOCGUNIT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) err = -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) if (put_user(ppp_unit_number(&ap->chan), p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) case TCFLSH:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) /* flush our buffers and the serial port's buffer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) if (arg == TCIOFLUSH || arg == TCOFLUSH)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) ppp_async_flush_output(ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) err = n_tty_ioctl_helper(tty, file, cmd, arg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) case FIONREAD:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) val = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) if (put_user(val, p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) /* Try the various mode ioctls */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) err = tty_mode_ioctl(tty, file, cmd, arg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) ap_put(ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) /* No kernel lock - fine */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) static __poll_t
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) ppp_asynctty_poll(struct tty_struct *tty, struct file *file, poll_table *wait)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) /* May sleep, don't call from interrupt level or with interrupts disabled */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) static void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) ppp_asynctty_receive(struct tty_struct *tty, const unsigned char *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) char *cflags, int count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) struct asyncppp *ap = ap_get(tty);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) if (!ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) spin_lock_irqsave(&ap->recv_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) ppp_async_input(ap, buf, cflags, count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) spin_unlock_irqrestore(&ap->recv_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) if (!skb_queue_empty(&ap->rqueue))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) tasklet_schedule(&ap->tsk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) ap_put(ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) tty_unthrottle(tty);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) static void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) ppp_asynctty_wakeup(struct tty_struct *tty)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) struct asyncppp *ap = ap_get(tty);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) if (!ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) set_bit(XMIT_WAKEUP, &ap->xmit_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) tasklet_schedule(&ap->tsk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) ap_put(ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) static struct tty_ldisc_ops ppp_ldisc = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) .owner = THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) .magic = TTY_LDISC_MAGIC,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) .name = "ppp",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) .open = ppp_asynctty_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) .close = ppp_asynctty_close,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) .hangup = ppp_asynctty_hangup,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) .read = ppp_asynctty_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) .write = ppp_asynctty_write,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) .ioctl = ppp_asynctty_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) .poll = ppp_asynctty_poll,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) .receive_buf = ppp_asynctty_receive,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) .write_wakeup = ppp_asynctty_wakeup,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) static int __init
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) ppp_async_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) err = tty_register_ldisc(N_PPP, &ppp_ldisc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) if (err != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) printk(KERN_ERR "PPP_async: error %d registering line disc.\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) * The following routines provide the PPP channel interface.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) static int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) ppp_async_ioctl(struct ppp_channel *chan, unsigned int cmd, unsigned long arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) struct asyncppp *ap = chan->private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) void __user *argp = (void __user *)arg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) int __user *p = argp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) int err, val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) u32 accm[8];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) err = -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) switch (cmd) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) case PPPIOCGFLAGS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) val = ap->flags | ap->rbits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) if (put_user(val, p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) case PPPIOCSFLAGS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) if (get_user(val, p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) ap->flags = val & ~SC_RCV_BITS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) spin_lock_irq(&ap->recv_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) ap->rbits = val & SC_RCV_BITS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) spin_unlock_irq(&ap->recv_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) case PPPIOCGASYNCMAP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) if (put_user(ap->xaccm[0], (u32 __user *)argp))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) case PPPIOCSASYNCMAP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) if (get_user(ap->xaccm[0], (u32 __user *)argp))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) case PPPIOCGRASYNCMAP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) if (put_user(ap->raccm, (u32 __user *)argp))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) case PPPIOCSRASYNCMAP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) if (get_user(ap->raccm, (u32 __user *)argp))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) case PPPIOCGXASYNCMAP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) if (copy_to_user(argp, ap->xaccm, sizeof(ap->xaccm)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) case PPPIOCSXASYNCMAP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) if (copy_from_user(accm, argp, sizeof(accm)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) accm[2] &= ~0x40000000U; /* can't escape 0x5e */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) accm[3] |= 0x60000000U; /* must escape 0x7d, 0x7e */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) memcpy(ap->xaccm, accm, sizeof(ap->xaccm));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) case PPPIOCGMRU:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) if (put_user(ap->mru, p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) case PPPIOCSMRU:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) if (get_user(val, p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) if (val < PPP_MRU)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) val = PPP_MRU;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) ap->mru = val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) err = -ENOTTY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) * This is called at softirq level to deliver received packets
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) * to the ppp_generic code, and to tell the ppp_generic code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) * if we can accept more output now.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) static void ppp_async_process(unsigned long arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) struct asyncppp *ap = (struct asyncppp *) arg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) /* process received packets */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) while ((skb = skb_dequeue(&ap->rqueue)) != NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) if (skb->cb[0])
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) ppp_input_error(&ap->chan, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) ppp_input(&ap->chan, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) /* try to push more stuff out */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) if (test_bit(XMIT_WAKEUP, &ap->xmit_flags) && ppp_async_push(ap))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) ppp_output_wakeup(&ap->chan);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) * Procedures for encapsulation and framing.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) * Procedure to encode the data for async serial transmission.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) * Does octet stuffing (escaping), puts the address/control bytes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) * on if A/C compression is disabled, and does protocol compression.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) * Assumes ap->tpkt != 0 on entry.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) * Returns 1 if we finished the current frame, 0 otherwise.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) #define PUT_BYTE(ap, buf, c, islcp) do { \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) if ((islcp && c < 0x20) || (ap->xaccm[c >> 5] & (1 << (c & 0x1f)))) {\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) *buf++ = PPP_ESCAPE; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) *buf++ = c ^ PPP_TRANS; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) } else \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) *buf++ = c; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) } while (0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) static int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) ppp_async_encode(struct asyncppp *ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) int fcs, i, count, c, proto;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) unsigned char *buf, *buflim;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) unsigned char *data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) int islcp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) buf = ap->obuf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) ap->olim = buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) ap->optr = buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) i = ap->tpkt_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) data = ap->tpkt->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) count = ap->tpkt->len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) fcs = ap->tfcs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) proto = get_unaligned_be16(data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) * LCP packets with code values between 1 (configure-reqest)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548) * and 7 (code-reject) must be sent as though no options
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) * had been negotiated.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) islcp = proto == PPP_LCP && 1 <= data[2] && data[2] <= 7;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) if (i == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) if (islcp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) async_lcp_peek(ap, data, count, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) * Start of a new packet - insert the leading FLAG
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) * character if necessary.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) if (islcp || flag_time == 0 ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) time_after_eq(jiffies, ap->last_xmit + flag_time))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) *buf++ = PPP_FLAG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) ap->last_xmit = jiffies;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) fcs = PPP_INITFCS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) * Put in the address/control bytes if necessary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) if ((ap->flags & SC_COMP_AC) == 0 || islcp) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) PUT_BYTE(ap, buf, 0xff, islcp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) fcs = PPP_FCS(fcs, 0xff);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) PUT_BYTE(ap, buf, 0x03, islcp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) fcs = PPP_FCS(fcs, 0x03);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) * Once we put in the last byte, we need to put in the FCS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) * and closing flag, so make sure there is at least 7 bytes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) * of free space in the output buffer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) buflim = ap->obuf + OBUFSIZE - 6;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) while (i < count && buf < buflim) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) c = data[i++];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) if (i == 1 && c == 0 && (ap->flags & SC_COMP_PROT))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) continue; /* compress protocol field */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) fcs = PPP_FCS(fcs, c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) PUT_BYTE(ap, buf, c, islcp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) if (i < count) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) * Remember where we are up to in this packet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) ap->olim = buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) ap->tpkt_pos = i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) ap->tfcs = fcs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) * We have finished the packet. Add the FCS and flag.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) fcs = ~fcs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) c = fcs & 0xff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) PUT_BYTE(ap, buf, c, islcp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) c = (fcs >> 8) & 0xff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) PUT_BYTE(ap, buf, c, islcp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) *buf++ = PPP_FLAG;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) ap->olim = buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) consume_skb(ap->tpkt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) ap->tpkt = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) * Transmit-side routines.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) * Send a packet to the peer over an async tty line.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) * Returns 1 iff the packet was accepted.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) * If the packet was not accepted, we will call ppp_output_wakeup
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) * at some later time.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) static int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) ppp_async_send(struct ppp_channel *chan, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631) struct asyncppp *ap = chan->private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633) ppp_async_push(ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) if (test_and_set_bit(XMIT_FULL, &ap->xmit_flags))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) return 0; /* already full */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) ap->tpkt = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) ap->tpkt_pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640) ppp_async_push(ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) * Push as much data as possible out to the tty.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) static int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648) ppp_async_push(struct asyncppp *ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) int avail, sent, done = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651) struct tty_struct *tty = ap->tty;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) int tty_stuffed = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655) * We can get called recursively here if the tty write
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) * function calls our wakeup function. This can happen
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) * for example on a pty with both the master and slave
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) * set to PPP line discipline.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) * We use the XMIT_BUSY bit to detect this and get out,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) * leaving the XMIT_WAKEUP bit set to tell the other
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) * instance that it may now be able to write more now.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) if (test_and_set_bit(XMIT_BUSY, &ap->xmit_flags))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665) spin_lock_bh(&ap->xmit_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) for (;;) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) if (test_and_clear_bit(XMIT_WAKEUP, &ap->xmit_flags))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668) tty_stuffed = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) if (!tty_stuffed && ap->optr < ap->olim) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670) avail = ap->olim - ap->optr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) sent = tty->ops->write(tty, ap->optr, avail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) if (sent < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674) goto flush; /* error, e.g. loss of CD */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675) ap->optr += sent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) if (sent < avail)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677) tty_stuffed = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680) if (ap->optr >= ap->olim && ap->tpkt) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) if (ppp_async_encode(ap)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) /* finished processing ap->tpkt */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) clear_bit(XMIT_FULL, &ap->xmit_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) done = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) * We haven't made any progress this time around.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) * Clear XMIT_BUSY to let other callers in, but
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691) * after doing so we have to check if anyone set
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) * XMIT_WAKEUP since we last checked it. If they
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) * did, we should try again to set XMIT_BUSY and go
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) * around again in case XMIT_BUSY was still set when
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) * the other caller tried.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) clear_bit(XMIT_BUSY, &ap->xmit_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) /* any more work to do? if not, exit the loop */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699) if (!(test_bit(XMIT_WAKEUP, &ap->xmit_flags) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700) (!tty_stuffed && ap->tpkt)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) /* more work to do, see if we can do it now */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703) if (test_and_set_bit(XMIT_BUSY, &ap->xmit_flags))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706) spin_unlock_bh(&ap->xmit_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) return done;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) flush:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) clear_bit(XMIT_BUSY, &ap->xmit_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711) if (ap->tpkt) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) kfree_skb(ap->tpkt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) ap->tpkt = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714) clear_bit(XMIT_FULL, &ap->xmit_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) done = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) ap->optr = ap->olim;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) spin_unlock_bh(&ap->xmit_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) return done;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) * Flush output from our internal buffers.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) * Called for the TCFLSH ioctl. Can be entered in parallel
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) * but this is covered by the xmit_lock.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) static void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) ppp_async_flush_output(struct asyncppp *ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730) int done = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) spin_lock_bh(&ap->xmit_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) ap->optr = ap->olim;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734) if (ap->tpkt != NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) kfree_skb(ap->tpkt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) ap->tpkt = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737) clear_bit(XMIT_FULL, &ap->xmit_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) done = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) spin_unlock_bh(&ap->xmit_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) if (done)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) ppp_output_wakeup(&ap->chan);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) * Receive-side routines.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749) /* see how many ordinary chars there are at the start of buf */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) static inline int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751) scan_ordinary(struct asyncppp *ap, const unsigned char *buf, int count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) int i, c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) for (i = 0; i < count; ++i) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756) c = buf[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) if (c == PPP_ESCAPE || c == PPP_FLAG ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758) (c < 0x20 && (ap->raccm & (1 << c)) != 0))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) return i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) /* called when a flag is seen - do end-of-packet processing */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765) static void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) process_input_packet(struct asyncppp *ap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769) unsigned char *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) unsigned int len, fcs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772) skb = ap->rpkt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) if (ap->state & (SC_TOSS | SC_ESCAPE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) if (skb == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777) return; /* 0-length packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) /* check the FCS */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) p = skb->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781) len = skb->len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782) if (len < 3)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) goto err; /* too short */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) fcs = PPP_INITFCS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785) for (; len > 0; --len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786) fcs = PPP_FCS(fcs, *p++);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) if (fcs != PPP_GOODFCS)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788) goto err; /* bad FCS */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) skb_trim(skb, skb->len - 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791) /* check for address/control and protocol compression */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792) p = skb->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) if (p[0] == PPP_ALLSTATIONS) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794) /* chop off address/control */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795) if (p[1] != PPP_UI || skb->len < 3)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797) p = skb_pull(skb, 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) /* If protocol field is not compressed, it can be LCP packet */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801) if (!(p[0] & 0x01)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) unsigned int proto;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804) if (skb->len < 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) proto = (p[0] << 8) + p[1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) if (proto == PPP_LCP)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808) async_lcp_peek(ap, p, skb->len, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811) /* queue the frame to be processed */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812) skb->cb[0] = ap->state;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) skb_queue_tail(&ap->rqueue, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) ap->rpkt = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815) ap->state = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818) err:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) /* frame had an error, remember that, reset SC_TOSS & SC_ESCAPE */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) ap->state = SC_PREV_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) if (skb) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822) /* make skb appear as freshly allocated */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) skb_trim(skb, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) skb_reserve(skb, - skb_headroom(skb));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) /* Called when the tty driver has data for us. Runs parallel with the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829) other ldisc functions but will not be re-entered */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) static void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) ppp_async_input(struct asyncppp *ap, const unsigned char *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833) char *flags, int count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836) int c, i, j, n, s, f;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) unsigned char *sp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 838)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 839) /* update bits used for 8-bit cleanness detection */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 840) if (~ap->rbits & SC_RCV_BITS) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 841) s = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 842) for (i = 0; i < count; ++i) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 843) c = buf[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 844) if (flags && flags[i] != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 845) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 846) s |= (c & 0x80)? SC_RCV_B7_1: SC_RCV_B7_0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 847) c = ((c >> 4) ^ c) & 0xf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 848) s |= (0x6996 & (1 << c))? SC_RCV_ODDP: SC_RCV_EVNP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 849) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 850) ap->rbits |= s;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 851) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 852)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 853) while (count > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 854) /* scan through and see how many chars we can do in bulk */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 855) if ((ap->state & SC_ESCAPE) && buf[0] == PPP_ESCAPE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 856) n = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 857) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 858) n = scan_ordinary(ap, buf, count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 859)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 860) f = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 861) if (flags && (ap->state & SC_TOSS) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 862) /* check the flags to see if any char had an error */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 863) for (j = 0; j < n; ++j)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 864) if ((f = flags[j]) != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 865) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 866) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 867) if (f != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 868) /* start tossing */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 869) ap->state |= SC_TOSS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 870)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 871) } else if (n > 0 && (ap->state & SC_TOSS) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 872) /* stuff the chars in the skb */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 873) skb = ap->rpkt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 874) if (!skb) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 875) skb = dev_alloc_skb(ap->mru + PPP_HDRLEN + 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 876) if (!skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 877) goto nomem;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 878) ap->rpkt = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 879) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 880) if (skb->len == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 881) /* Try to get the payload 4-byte aligned.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 882) * This should match the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 883) * PPP_ALLSTATIONS/PPP_UI/compressed tests in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 884) * process_input_packet, but we do not have
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 885) * enough chars here to test buf[1] and buf[2].
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 886) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 887) if (buf[0] != PPP_ALLSTATIONS)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 888) skb_reserve(skb, 2 + (buf[0] & 1));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 889) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 890) if (n > skb_tailroom(skb)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 891) /* packet overflowed MRU */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 892) ap->state |= SC_TOSS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 893) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 894) sp = skb_put_data(skb, buf, n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 895) if (ap->state & SC_ESCAPE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 896) sp[0] ^= PPP_TRANS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 897) ap->state &= ~SC_ESCAPE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 898) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 899) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 900) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 901)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 902) if (n >= count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 903) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 904)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 905) c = buf[n];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 906) if (flags != NULL && flags[n] != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 907) ap->state |= SC_TOSS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 908) } else if (c == PPP_FLAG) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 909) process_input_packet(ap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 910) } else if (c == PPP_ESCAPE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 911) ap->state |= SC_ESCAPE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 912) } else if (I_IXON(ap->tty)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 913) if (c == START_CHAR(ap->tty))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 914) start_tty(ap->tty);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 915) else if (c == STOP_CHAR(ap->tty))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 916) stop_tty(ap->tty);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 917) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 918) /* otherwise it's a char in the recv ACCM */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 919) ++n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 920)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 921) buf += n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 922) if (flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 923) flags += n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 924) count -= n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 925) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 926) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 927)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 928) nomem:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 929) printk(KERN_ERR "PPPasync: no memory (input pkt)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 930) ap->state |= SC_TOSS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 931) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 932)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 933) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 934) * We look at LCP frames going past so that we can notice
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 935) * and react to the LCP configure-ack from the peer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 936) * In the situation where the peer has been sent a configure-ack
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 937) * already, LCP is up once it has sent its configure-ack
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 938) * so the immediately following packet can be sent with the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 939) * configured LCP options. This allows us to process the following
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 940) * packet correctly without pppd needing to respond quickly.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 941) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 942) * We only respond to the received configure-ack if we have just
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 943) * sent a configure-request, and the configure-ack contains the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 944) * same data (this is checked using a 16-bit crc of the data).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 945) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 946) #define CONFREQ 1 /* LCP code field values */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 947) #define CONFACK 2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 948) #define LCP_MRU 1 /* LCP option numbers */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 949) #define LCP_ASYNCMAP 2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 950)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 951) static void async_lcp_peek(struct asyncppp *ap, unsigned char *data,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 952) int len, int inbound)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 953) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 954) int dlen, fcs, i, code;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 955) u32 val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 956)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 957) data += 2; /* skip protocol bytes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 958) len -= 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 959) if (len < 4) /* 4 = code, ID, length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 960) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 961) code = data[0];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 962) if (code != CONFACK && code != CONFREQ)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 963) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 964) dlen = get_unaligned_be16(data + 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 965) if (len < dlen)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 966) return; /* packet got truncated or length is bogus */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 967)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 968) if (code == (inbound? CONFACK: CONFREQ)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 969) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 970) * sent confreq or received confack:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 971) * calculate the crc of the data from the ID field on.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 972) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 973) fcs = PPP_INITFCS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 974) for (i = 1; i < dlen; ++i)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 975) fcs = PPP_FCS(fcs, data[i]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 976)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 977) if (!inbound) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 978) /* outbound confreq - remember the crc for later */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 979) ap->lcp_fcs = fcs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 980) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 981) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 982)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 983) /* received confack, check the crc */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 984) fcs ^= ap->lcp_fcs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 985) ap->lcp_fcs = -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 986) if (fcs != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 987) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 988) } else if (inbound)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 989) return; /* not interested in received confreq */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 990)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 991) /* process the options in the confack */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 992) data += 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 993) dlen -= 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 994) /* data[0] is code, data[1] is length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 995) while (dlen >= 2 && dlen >= data[1] && data[1] >= 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 996) switch (data[0]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 997) case LCP_MRU:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 998) val = get_unaligned_be16(data + 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 999) if (inbound)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1000) ap->mru = val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1001) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1002) ap->chan.mtu = val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1003) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1004) case LCP_ASYNCMAP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1005) val = get_unaligned_be32(data + 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1006) if (inbound)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1007) ap->raccm = val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1008) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1009) ap->xaccm[0] = val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1010) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1011) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1012) dlen -= data[1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1013) data += data[1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1014) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1015) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1016)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1017) static void __exit ppp_async_cleanup(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1018) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1019) if (tty_unregister_ldisc(N_PPP) != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1020) printk(KERN_ERR "failed to unregister PPP line discipline\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1021) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1022)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1023) module_init(ppp_async_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1024) module_exit(ppp_async_cleanup);
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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