| 1 |
/* |
| 2 |
* sheep_net.c - Linux driver for SheepShaver/Basilisk II networking (access to raw Ethernet packets) |
| 3 |
* |
| 4 |
* sheep_net (C) 1999-2004 Mar"c" Hellwig and Christian Bauer |
| 5 |
* |
| 6 |
* This program is free software; you can redistribute it and/or modify |
| 7 |
* it under the terms of the GNU General Public License as published by |
| 8 |
* the Free Software Foundation; either version 2 of the License, or |
| 9 |
* (at your option) any later version. |
| 10 |
* |
| 11 |
* This program is distributed in the hope that it will be useful, |
| 12 |
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 |
* GNU General Public License for more details. |
| 15 |
* |
| 16 |
* You should have received a copy of the GNU General Public License |
| 17 |
* along with this program; if not, write to the Free Software |
| 18 |
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 |
*/ |
| 20 |
|
| 21 |
/* determine whether to use checksummed versions of kernel symbols */ |
| 22 |
#include <linux/config.h> |
| 23 |
|
| 24 |
#if defined(CONFIG_MODVERSIONS) && !defined(MODVERSIONS) |
| 25 |
#define MODVERSIONS |
| 26 |
#endif |
| 27 |
|
| 28 |
#if defined(MODVERSIONS) |
| 29 |
#include <linux/modversions.h> |
| 30 |
#endif |
| 31 |
|
| 32 |
/* modversions.h redefines kernel symbols. Now include other headers */ |
| 33 |
#include <linux/kernel.h> |
| 34 |
#include <linux/module.h> |
| 35 |
#include <linux/version.h> |
| 36 |
|
| 37 |
#include <linux/types.h> |
| 38 |
#include <linux/miscdevice.h> |
| 39 |
#include <linux/netdevice.h> |
| 40 |
#include <linux/etherdevice.h> |
| 41 |
#include <linux/if_ether.h> |
| 42 |
#include <linux/if_arp.h> |
| 43 |
#include <linux/fs.h> |
| 44 |
#include <linux/poll.h> |
| 45 |
#include <linux/init.h> |
| 46 |
#include <net/sock.h> |
| 47 |
#include <asm/uaccess.h> |
| 48 |
#include <asm/ioctls.h> |
| 49 |
#include <net/arp.h> |
| 50 |
#include <net/ip.h> |
| 51 |
#include <linux/in.h> |
| 52 |
#include <linux/wait.h> |
| 53 |
|
| 54 |
MODULE_AUTHOR("Christian Bauer"); |
| 55 |
MODULE_DESCRIPTION("Pseudo ethernet device for emulators"); |
| 56 |
|
| 57 |
/* Compatibility glue */ |
| 58 |
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0) |
| 59 |
#define LINUX_26 |
| 60 |
#endif |
| 61 |
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,0) |
| 62 |
#define LINUX_24 |
| 63 |
#else |
| 64 |
#define net_device device |
| 65 |
typedef struct wait_queue *wait_queue_head_t; |
| 66 |
#define init_waitqueue_head(x) *(x)=NULL |
| 67 |
#endif |
| 68 |
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,9) |
| 69 |
#define eth_hdr(skb) (skb)->mac.ethernet |
| 70 |
#endif |
| 71 |
|
| 72 |
#ifdef LINUX_26 |
| 73 |
#define compat_sk_alloc(a,b,c) sk_alloc( (a), (b), (c), NULL ) |
| 74 |
#define skt_set_dead(skt) do {} while(0) |
| 75 |
#define wmem_alloc sk_wmem_alloc |
| 76 |
#else |
| 77 |
#define compat_sk_alloc sk_alloc |
| 78 |
#define skt_set_dead(skt) (skt)->dead = 1 |
| 79 |
#endif |
| 80 |
|
| 81 |
#define DEBUG 0 |
| 82 |
|
| 83 |
#define bug printk |
| 84 |
#if DEBUG |
| 85 |
#define D(x) (x); |
| 86 |
#else |
| 87 |
#define D(x) ; |
| 88 |
#endif |
| 89 |
|
| 90 |
|
| 91 |
/* Constants */ |
| 92 |
#define SHEEP_NET_MINOR 198 /* Driver minor number */ |
| 93 |
#define MAX_QUEUE 32 /* Maximum number of packets in queue */ |
| 94 |
#define PROT_MAGIC 1520 /* Our "magic" protocol type */ |
| 95 |
|
| 96 |
#define ETH_ADDR_MULTICAST 0x1 |
| 97 |
#define ETH_ADDR_LOCALLY_DEFINED 0x02 |
| 98 |
|
| 99 |
#define SIOC_MOL_GET_IPFILTER SIOCDEVPRIVATE |
| 100 |
#define SIOC_MOL_SET_IPFILTER (SIOCDEVPRIVATE + 1) |
| 101 |
|
| 102 |
/* Prototypes */ |
| 103 |
static int sheep_net_open(struct inode *inode, struct file *f); |
| 104 |
static int sheep_net_release(struct inode *inode, struct file *f); |
| 105 |
static ssize_t sheep_net_read(struct file *f, char *buf, size_t count, loff_t *off); |
| 106 |
static ssize_t sheep_net_write(struct file *f, const char *buf, size_t count, loff_t *off); |
| 107 |
static unsigned int sheep_net_poll(struct file *f, struct poll_table_struct *wait); |
| 108 |
static int sheep_net_ioctl(struct inode *inode, struct file *f, unsigned int code, unsigned long arg); |
| 109 |
static int sheep_net_receiver(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt); |
| 110 |
|
| 111 |
|
| 112 |
/* |
| 113 |
* Driver private variables |
| 114 |
*/ |
| 115 |
|
| 116 |
struct SheepVars { |
| 117 |
/* IMPORTANT: the packet_type struct must go first. It no longer |
| 118 |
(2.6) contains * a data field so we typecast to get the SheepVars |
| 119 |
struct */ |
| 120 |
struct packet_type pt; /* Receiver packet type */ |
| 121 |
struct net_device *ether; /* The Ethernet device we're attached to */ |
| 122 |
struct sock *skt; /* Socket for communication with Ethernet card */ |
| 123 |
struct sk_buff_head queue; /* Receiver packet queue */ |
| 124 |
wait_queue_head_t wait; /* Wait queue for blocking read operations */ |
| 125 |
u32 ipfilter; /* Only receive IP packets destined for this address (host byte order) */ |
| 126 |
char eth_addr[6]; /* Hardware address of the Ethernet card */ |
| 127 |
char fake_addr[6]; /* Local faked hardware address (what SheepShaver sees) */ |
| 128 |
}; |
| 129 |
|
| 130 |
|
| 131 |
/* |
| 132 |
* file_operations structure - has function pointers to the |
| 133 |
* various entry points for device operations |
| 134 |
*/ |
| 135 |
|
| 136 |
static struct file_operations sheep_net_fops = { |
| 137 |
.owner = THIS_MODULE, |
| 138 |
.read = sheep_net_read, |
| 139 |
.write = sheep_net_write, |
| 140 |
.poll = sheep_net_poll, |
| 141 |
.ioctl = sheep_net_ioctl, |
| 142 |
.open = sheep_net_open, |
| 143 |
.release = sheep_net_release, |
| 144 |
}; |
| 145 |
|
| 146 |
|
| 147 |
/* |
| 148 |
* miscdevice structure for driver initialization |
| 149 |
*/ |
| 150 |
|
| 151 |
static struct miscdevice sheep_net_device = { |
| 152 |
.minor = SHEEP_NET_MINOR, /* minor number */ |
| 153 |
.name = "sheep_net", /* name */ |
| 154 |
.fops = &sheep_net_fops |
| 155 |
}; |
| 156 |
|
| 157 |
|
| 158 |
/* |
| 159 |
* Initialize module |
| 160 |
*/ |
| 161 |
|
| 162 |
int init_module(void) |
| 163 |
{ |
| 164 |
int ret; |
| 165 |
|
| 166 |
/* Register driver */ |
| 167 |
ret = misc_register(&sheep_net_device); |
| 168 |
D(bug("Sheep net driver installed\n")); |
| 169 |
return ret; |
| 170 |
} |
| 171 |
|
| 172 |
|
| 173 |
/* |
| 174 |
* Deinitialize module |
| 175 |
*/ |
| 176 |
|
| 177 |
void cleanup_module(void) |
| 178 |
{ |
| 179 |
/* Unregister driver */ |
| 180 |
misc_deregister(&sheep_net_device); |
| 181 |
D(bug("Sheep net driver removed\n")); |
| 182 |
} |
| 183 |
|
| 184 |
|
| 185 |
/* |
| 186 |
* Driver open() function |
| 187 |
*/ |
| 188 |
|
| 189 |
static int sheep_net_open(struct inode *inode, struct file *f) |
| 190 |
{ |
| 191 |
struct SheepVars *v; |
| 192 |
D(bug("sheep_net: open\n")); |
| 193 |
|
| 194 |
/* Must be opened with read permissions */ |
| 195 |
if ((f->f_flags & O_ACCMODE) == O_WRONLY) |
| 196 |
return -EPERM; |
| 197 |
|
| 198 |
/* Allocate private variables */ |
| 199 |
v = (struct SheepVars *)(f->private_data = kmalloc(sizeof(struct SheepVars), GFP_USER)); |
| 200 |
if (v == NULL) |
| 201 |
return -ENOMEM; |
| 202 |
memset(v, 0, sizeof(struct SheepVars)); |
| 203 |
skb_queue_head_init(&v->queue); |
| 204 |
init_waitqueue_head(&v->wait); |
| 205 |
v->fake_addr[0] = 0xfe; |
| 206 |
v->fake_addr[1] = 0xfd; |
| 207 |
v->fake_addr[2] = 0xde; |
| 208 |
v->fake_addr[3] = 0xad; |
| 209 |
v->fake_addr[4] = 0xbe; |
| 210 |
v->fake_addr[5] = 0xef; |
| 211 |
|
| 212 |
/* Yes, we're open */ |
| 213 |
#ifndef LINUX_26 |
| 214 |
MOD_INC_USE_COUNT; |
| 215 |
#endif |
| 216 |
return 0; |
| 217 |
} |
| 218 |
|
| 219 |
|
| 220 |
/* |
| 221 |
* Driver release() function |
| 222 |
*/ |
| 223 |
|
| 224 |
static int sheep_net_release(struct inode *inode, struct file *f) |
| 225 |
{ |
| 226 |
struct SheepVars *v = (struct SheepVars *)f->private_data; |
| 227 |
struct sk_buff *skb; |
| 228 |
D(bug("sheep_net: close\n")); |
| 229 |
|
| 230 |
/* Detach from Ethernet card */ |
| 231 |
if (v->ether) { |
| 232 |
dev_remove_pack(&v->pt); |
| 233 |
sk_free(v->skt); |
| 234 |
v->skt = NULL; |
| 235 |
#ifdef LINUX_24 |
| 236 |
dev_put( v->ether ); |
| 237 |
#endif |
| 238 |
v->ether = NULL; |
| 239 |
} |
| 240 |
|
| 241 |
/* Empty packet queue */ |
| 242 |
while ((skb = skb_dequeue(&v->queue)) != NULL) |
| 243 |
dev_kfree_skb(skb); |
| 244 |
|
| 245 |
/* Free private variables */ |
| 246 |
kfree(v); |
| 247 |
|
| 248 |
/* Sorry, we're closed */ |
| 249 |
#ifndef LINUX_26 |
| 250 |
MOD_DEC_USE_COUNT; |
| 251 |
#endif |
| 252 |
return 0; |
| 253 |
} |
| 254 |
|
| 255 |
|
| 256 |
/* |
| 257 |
* Check whether an Ethernet address is the local (attached) one or |
| 258 |
* the fake one |
| 259 |
*/ |
| 260 |
|
| 261 |
static inline int is_local_addr(struct SheepVars *v, void *a) |
| 262 |
{ |
| 263 |
return memcmp(a, v->eth_addr, 6) == 0; |
| 264 |
} |
| 265 |
|
| 266 |
static inline int is_fake_addr(struct SheepVars *v, void *a) |
| 267 |
{ |
| 268 |
return memcmp(a, v->fake_addr, 6) == 0; |
| 269 |
} |
| 270 |
|
| 271 |
|
| 272 |
/* |
| 273 |
* Outgoing packet. Replace the fake enet addr with the real local one. |
| 274 |
*/ |
| 275 |
|
| 276 |
static inline void do_demasq(struct SheepVars *v, u8 *p) |
| 277 |
{ |
| 278 |
memcpy(p, v->eth_addr, 6); |
| 279 |
} |
| 280 |
|
| 281 |
static void demasquerade(struct SheepVars *v, struct sk_buff *skb) |
| 282 |
{ |
| 283 |
u8 *p = skb->mac.raw; |
| 284 |
int proto = (p[12] << 8) | p[13]; |
| 285 |
|
| 286 |
do_demasq(v, p + 6); /* source address */ |
| 287 |
|
| 288 |
/* Need to fix ARP packets */ |
| 289 |
if (proto == ETH_P_ARP) { |
| 290 |
if (is_fake_addr(v, p + 14 + 8)) /* sender HW-addr */ |
| 291 |
do_demasq(v, p + 14 + 8); |
| 292 |
} |
| 293 |
|
| 294 |
/* ...and AARPs (snap code: 0x00,0x00,0x00,0x80,0xF3) */ |
| 295 |
if (p[17] == 0 && p[18] == 0 && p[19] == 0 && p[20] == 0x80 && p[21] == 0xf3) { |
| 296 |
/* XXX: we should perhaps look for the 802 frame too */ |
| 297 |
if (is_fake_addr(v, p + 30)) |
| 298 |
do_demasq(v, p + 30); /* sender HW-addr */ |
| 299 |
} |
| 300 |
} |
| 301 |
|
| 302 |
|
| 303 |
/* |
| 304 |
* Incoming packet. Replace the local enet addr with the fake one. |
| 305 |
*/ |
| 306 |
|
| 307 |
static inline void do_masq(struct SheepVars *v, u8 *p) |
| 308 |
{ |
| 309 |
memcpy(p, v->fake_addr, 6); |
| 310 |
} |
| 311 |
|
| 312 |
static void masquerade(struct SheepVars *v, struct sk_buff *skb) |
| 313 |
{ |
| 314 |
u8 *p = skb->mac.raw; |
| 315 |
if (!(p[0] & ETH_ADDR_MULTICAST)) |
| 316 |
do_masq(v, p); /* destination address */ |
| 317 |
|
| 318 |
/* XXX: reverse ARP might need to be fixed */ |
| 319 |
} |
| 320 |
|
| 321 |
|
| 322 |
/* |
| 323 |
* Driver read() function |
| 324 |
*/ |
| 325 |
|
| 326 |
static ssize_t sheep_net_read(struct file *f, char *buf, size_t count, loff_t *off) |
| 327 |
{ |
| 328 |
struct SheepVars *v = (struct SheepVars *)f->private_data; |
| 329 |
struct sk_buff *skb; |
| 330 |
|
| 331 |
D(bug("sheep_net: read\n")); |
| 332 |
|
| 333 |
for (;;) { |
| 334 |
|
| 335 |
/* Get next packet from queue */ |
| 336 |
skb = skb_dequeue(&v->queue); |
| 337 |
if (skb != NULL || (f->f_flags & O_NONBLOCK)) |
| 338 |
break; |
| 339 |
|
| 340 |
/* No packet in queue and in blocking mode, so block */ |
| 341 |
interruptible_sleep_on(&v->wait); |
| 342 |
|
| 343 |
/* Signal received? Then bail out */ |
| 344 |
if (signal_pending(current)) |
| 345 |
return -EINTR; |
| 346 |
} |
| 347 |
if (skb == NULL) |
| 348 |
return -EAGAIN; |
| 349 |
|
| 350 |
/* Pass packet to caller */ |
| 351 |
if (count > skb->len) |
| 352 |
count = skb->len; |
| 353 |
if (copy_to_user(buf, skb->data, count)) |
| 354 |
count = -EFAULT; |
| 355 |
dev_kfree_skb(skb); |
| 356 |
return count; |
| 357 |
} |
| 358 |
|
| 359 |
|
| 360 |
/* |
| 361 |
* Driver write() function |
| 362 |
*/ |
| 363 |
|
| 364 |
static ssize_t sheep_net_write(struct file *f, const char *buf, size_t count, loff_t *off) |
| 365 |
{ |
| 366 |
struct SheepVars *v = (struct SheepVars *)f->private_data; |
| 367 |
struct sk_buff *skb; |
| 368 |
char *p; |
| 369 |
D(bug("sheep_net: write\n")); |
| 370 |
|
| 371 |
/* Check packet size */ |
| 372 |
if (count < sizeof(struct ethhdr)) |
| 373 |
return -EINVAL; |
| 374 |
if (count > 1514) { |
| 375 |
printk("sheep_net_write: packet size > 1514\n"); |
| 376 |
count = 1514; |
| 377 |
} |
| 378 |
|
| 379 |
/* Interface active? */ |
| 380 |
if (v->ether == NULL) |
| 381 |
return count; |
| 382 |
|
| 383 |
/* Allocate buffer for packet */ |
| 384 |
skb = dev_alloc_skb(count); |
| 385 |
if (skb == NULL) |
| 386 |
return -ENOBUFS; |
| 387 |
|
| 388 |
/* Stuff packet in buffer */ |
| 389 |
p = skb_put(skb, count); |
| 390 |
if (copy_from_user(p, buf, count)) { |
| 391 |
kfree_skb(skb); |
| 392 |
return -EFAULT; |
| 393 |
} |
| 394 |
|
| 395 |
/* Transmit packet */ |
| 396 |
atomic_add(skb->truesize, &v->skt->wmem_alloc); |
| 397 |
skb->sk = v->skt; |
| 398 |
skb->dev = v->ether; |
| 399 |
skb->priority = 0; |
| 400 |
skb->nh.raw = skb->h.raw = skb->data + v->ether->hard_header_len; |
| 401 |
skb->mac.raw = skb->data; |
| 402 |
|
| 403 |
/* Base the IP-filtering on the IP address in any outgoing ARP packets */ |
| 404 |
if (eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) { |
| 405 |
u8 *p = &skb->data[14+14]; /* source IP address */ |
| 406 |
u32 ip = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]; |
| 407 |
if (ip != v->ipfilter) { |
| 408 |
v->ipfilter = ip; |
| 409 |
printk("sheep_net: ipfilter set to %d.%d.%d.%d\n", (ip >> 24) & 0xff, (ip >> 16) & 0xff, (ip >> 8) & 0xff, ip & 0xff); |
| 410 |
} |
| 411 |
} |
| 412 |
|
| 413 |
/* Is this packet addressed solely to the local host? */ |
| 414 |
if (is_local_addr(v, skb->data) && !(skb->data[0] & ETH_ADDR_MULTICAST)) { |
| 415 |
skb->protocol = eth_type_trans(skb, v->ether); |
| 416 |
netif_rx(skb); |
| 417 |
return count; |
| 418 |
} |
| 419 |
if (skb->data[0] & ETH_ADDR_MULTICAST) { |
| 420 |
/* We can't clone the skb since we will manipulate the data below */ |
| 421 |
struct sk_buff *lskb = skb_copy(skb, GFP_ATOMIC); |
| 422 |
if (lskb) { |
| 423 |
lskb->protocol = eth_type_trans(lskb, v->ether); |
| 424 |
netif_rx(lskb); |
| 425 |
} |
| 426 |
} |
| 427 |
|
| 428 |
/* Outgoing packet (will be on the net) */ |
| 429 |
demasquerade(v, skb); |
| 430 |
|
| 431 |
skb->protocol = PROT_MAGIC; /* Magic value (we can recognize the packet in sheep_net_receiver) */ |
| 432 |
dev_queue_xmit(skb); |
| 433 |
return count; |
| 434 |
} |
| 435 |
|
| 436 |
|
| 437 |
/* |
| 438 |
* Driver poll() function |
| 439 |
*/ |
| 440 |
|
| 441 |
static unsigned int sheep_net_poll(struct file *f, struct poll_table_struct *wait) |
| 442 |
{ |
| 443 |
struct SheepVars *v = (struct SheepVars *)f->private_data; |
| 444 |
D(bug("sheep_net: poll\n")); |
| 445 |
|
| 446 |
/* Packets in queue? Then return */ |
| 447 |
if (!skb_queue_empty(&v->queue)) |
| 448 |
return POLLIN | POLLRDNORM; |
| 449 |
|
| 450 |
/* Otherwise wait for packet */ |
| 451 |
poll_wait(f, &v->wait, wait); |
| 452 |
if (!skb_queue_empty(&v->queue)) |
| 453 |
return POLLIN | POLLRDNORM; |
| 454 |
else |
| 455 |
return 0; |
| 456 |
} |
| 457 |
|
| 458 |
|
| 459 |
/* |
| 460 |
* Driver ioctl() function |
| 461 |
*/ |
| 462 |
|
| 463 |
static int sheep_net_ioctl(struct inode *inode, struct file *f, unsigned int code, unsigned long arg) |
| 464 |
{ |
| 465 |
struct SheepVars *v = (struct SheepVars *)f->private_data; |
| 466 |
D(bug("sheep_net: ioctl %04x\n", code)); |
| 467 |
|
| 468 |
switch (code) { |
| 469 |
|
| 470 |
/* Attach to Ethernet card |
| 471 |
arg: pointer to name of Ethernet device (char[20]) */ |
| 472 |
case SIOCSIFLINK: { |
| 473 |
char name[20]; |
| 474 |
int err; |
| 475 |
|
| 476 |
/* Already attached? */ |
| 477 |
if (v->ether) |
| 478 |
return -EBUSY; |
| 479 |
|
| 480 |
/* Get Ethernet card name */ |
| 481 |
if (copy_from_user(name, (void *)arg, 20)) |
| 482 |
return -EFAULT; |
| 483 |
name[19] = 0; |
| 484 |
|
| 485 |
/* Find card */ |
| 486 |
#ifdef LINUX_24 |
| 487 |
v->ether = dev_get_by_name(name); |
| 488 |
#else |
| 489 |
dev_lock_list(); |
| 490 |
v->ether = dev_get(name); |
| 491 |
#endif |
| 492 |
if (v->ether == NULL) { |
| 493 |
err = -ENODEV; |
| 494 |
goto error; |
| 495 |
} |
| 496 |
|
| 497 |
/* Is it Ethernet? */ |
| 498 |
if (v->ether->type != ARPHRD_ETHER) { |
| 499 |
err = -EINVAL; |
| 500 |
goto error; |
| 501 |
} |
| 502 |
|
| 503 |
/* Remember the card's hardware address */ |
| 504 |
memcpy(v->eth_addr, v->ether->dev_addr, 6); |
| 505 |
|
| 506 |
/* Allocate socket */ |
| 507 |
v->skt = compat_sk_alloc(0, GFP_USER, 1); |
| 508 |
if (v->skt == NULL) { |
| 509 |
err = -ENOMEM; |
| 510 |
goto error; |
| 511 |
} |
| 512 |
skt_set_dead(v->skt->dead); |
| 513 |
|
| 514 |
/* Attach packet handler */ |
| 515 |
v->pt.type = htons(ETH_P_ALL); |
| 516 |
v->pt.dev = v->ether; |
| 517 |
v->pt.func = sheep_net_receiver; |
| 518 |
dev_add_pack(&v->pt); |
| 519 |
#ifndef LINUX_24 |
| 520 |
dev_unlock_list(); |
| 521 |
#endif |
| 522 |
return 0; |
| 523 |
|
| 524 |
error: |
| 525 |
#ifdef LINUX_24 |
| 526 |
if (v->ether) |
| 527 |
dev_put(v->ether); |
| 528 |
#else |
| 529 |
dev_unlock_list(); |
| 530 |
#endif |
| 531 |
v->ether = NULL; |
| 532 |
return err; |
| 533 |
} |
| 534 |
|
| 535 |
/* Get hardware address of the sheep_net module |
| 536 |
arg: pointer to buffer (6 bytes) to store address */ |
| 537 |
case SIOCGIFADDR: |
| 538 |
if (copy_to_user((void *)arg, v->fake_addr, 6)) |
| 539 |
return -EFAULT; |
| 540 |
return 0; |
| 541 |
|
| 542 |
/* Set the hardware address of the sheep_net module |
| 543 |
arg: pointer to new address (6 bytes) */ |
| 544 |
case SIOCSIFADDR: |
| 545 |
if (copy_from_user(v->fake_addr, (void*)arg, 6)) |
| 546 |
return -EFAULT; |
| 547 |
return 0; |
| 548 |
|
| 549 |
/* Add multicast address |
| 550 |
arg: pointer to address (6 bytes) */ |
| 551 |
case SIOCADDMULTI: { |
| 552 |
char addr[6]; |
| 553 |
if (v->ether == NULL) |
| 554 |
return -ENODEV; |
| 555 |
if (copy_from_user(addr, (void *)arg, 6)) |
| 556 |
return -EFAULT; |
| 557 |
return dev_mc_add(v->ether, addr, 6, 0); |
| 558 |
} |
| 559 |
|
| 560 |
/* Remove multicast address |
| 561 |
arg: pointer to address (6 bytes) */ |
| 562 |
case SIOCDELMULTI: { |
| 563 |
char addr[6]; |
| 564 |
if (v->ether == NULL) |
| 565 |
return -ENODEV; |
| 566 |
if (copy_from_user(addr, (void *)arg, 6)) |
| 567 |
return -EFAULT; |
| 568 |
return dev_mc_delete(v->ether, addr, 6, 0); |
| 569 |
} |
| 570 |
|
| 571 |
/* Return size of first packet in queue */ |
| 572 |
case FIONREAD: { |
| 573 |
int count = 0; |
| 574 |
struct sk_buff *skb; |
| 575 |
#ifdef LINUX_24 |
| 576 |
unsigned long flags; |
| 577 |
spin_lock_irqsave(&v->queue.lock, flags); |
| 578 |
#else |
| 579 |
cli(); |
| 580 |
#endif |
| 581 |
skb = skb_peek(&v->queue); |
| 582 |
if (skb) |
| 583 |
count = skb->len; |
| 584 |
#ifdef LINUX_24 |
| 585 |
spin_unlock_irqrestore(&v->queue.lock, flags); |
| 586 |
#else |
| 587 |
sti(); |
| 588 |
#endif |
| 589 |
return put_user(count, (int *)arg); |
| 590 |
} |
| 591 |
|
| 592 |
case SIOC_MOL_GET_IPFILTER: |
| 593 |
return put_user(v->ipfilter, (int *)arg); |
| 594 |
|
| 595 |
case SIOC_MOL_SET_IPFILTER: |
| 596 |
v->ipfilter = arg; |
| 597 |
return 0; |
| 598 |
|
| 599 |
default: |
| 600 |
return -ENOIOCTLCMD; |
| 601 |
} |
| 602 |
} |
| 603 |
|
| 604 |
|
| 605 |
/* |
| 606 |
* Packet receiver function |
| 607 |
*/ |
| 608 |
|
| 609 |
static int sheep_net_receiver(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt) |
| 610 |
{ |
| 611 |
struct SheepVars *v = (struct SheepVars *)pt; |
| 612 |
struct sk_buff *skb2; |
| 613 |
int fake; |
| 614 |
int multicast; |
| 615 |
D(bug("sheep_net: packet received\n")); |
| 616 |
|
| 617 |
multicast = (eth_hdr(skb)->h_dest[0] & ETH_ADDR_MULTICAST); |
| 618 |
fake = is_fake_addr(v, ð_hdr(skb)->h_dest); |
| 619 |
|
| 620 |
/* Packet sent by us? Then discard */ |
| 621 |
if (is_fake_addr(v, ð_hdr(skb)->h_source) || skb->protocol == PROT_MAGIC) |
| 622 |
goto drop; |
| 623 |
|
| 624 |
/* If the packet is not meant for this host, discard it */ |
| 625 |
if (!is_local_addr(v, ð_hdr(skb)->h_dest) && !multicast && !fake) |
| 626 |
goto drop; |
| 627 |
|
| 628 |
/* Discard packets if queue gets too full */ |
| 629 |
if (skb_queue_len(&v->queue) > MAX_QUEUE) |
| 630 |
goto drop; |
| 631 |
|
| 632 |
/* Apply any filters here (if fake is true, then we *know* we want this packet) */ |
| 633 |
if (!fake) { |
| 634 |
if ((skb->protocol == htons(ETH_P_IP)) |
| 635 |
&& (!v->ipfilter || (ntohl(skb->h.ipiph->daddr) != v->ipfilter && !multicast))) |
| 636 |
goto drop; |
| 637 |
} |
| 638 |
|
| 639 |
/* Masquerade (we are typically a clone - best to make a real copy) */ |
| 640 |
skb2 = skb_copy(skb, GFP_ATOMIC); |
| 641 |
if (!skb2) |
| 642 |
goto drop; |
| 643 |
kfree_skb(skb); |
| 644 |
skb = skb2; |
| 645 |
masquerade(v, skb); |
| 646 |
|
| 647 |
/* We also want the Ethernet header */ |
| 648 |
skb_push(skb, skb->data - skb->mac.raw); |
| 649 |
|
| 650 |
/* Enqueue packet */ |
| 651 |
skb_queue_tail(&v->queue, skb); |
| 652 |
|
| 653 |
/* Unblock blocked read */ |
| 654 |
wake_up(&v->wait); |
| 655 |
return 0; |
| 656 |
|
| 657 |
drop: |
| 658 |
kfree_skb(skb); |
| 659 |
return 0; |
| 660 |
} |
| 661 |
|
| 662 |
MODULE_LICENSE("GPL"); |
