xref: /linux/arch/um/drivers/vector_user.c (revision 71dfa617ea9f18e4585fe78364217cd32b1fc382)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4  */
5 
6 #include <stdbool.h>
7 #include <stdio.h>
8 #include <unistd.h>
9 #include <stdarg.h>
10 #include <errno.h>
11 #include <stddef.h>
12 #include <string.h>
13 #include <sys/ioctl.h>
14 #include <net/if.h>
15 #include <linux/if_tun.h>
16 #include <arpa/inet.h>
17 #include <sys/types.h>
18 #include <sys/stat.h>
19 #include <fcntl.h>
20 #include <sys/socket.h>
21 #include <sys/un.h>
22 #include <netinet/ip.h>
23 #include <linux/if_ether.h>
24 #include <linux/if_packet.h>
25 #include <sys/wait.h>
26 #include <sys/uio.h>
27 #include <linux/virtio_net.h>
28 #include <netdb.h>
29 #include <stdlib.h>
30 #include <os.h>
31 #include <limits.h>
32 #include <um_malloc.h>
33 #include "vector_user.h"
34 
35 #define ID_GRE 0
36 #define ID_L2TPV3 1
37 #define ID_BESS 2
38 #define ID_MAX 2
39 
40 #define TOKEN_IFNAME "ifname"
41 #define TOKEN_SCRIPT "ifup"
42 
43 #define TRANS_RAW "raw"
44 #define TRANS_RAW_LEN strlen(TRANS_RAW)
45 
46 #define TRANS_FD "fd"
47 #define TRANS_FD_LEN strlen(TRANS_FD)
48 
49 #define VNET_HDR_FAIL "could not enable vnet headers on fd %d"
50 #define TUN_GET_F_FAIL "tapraw: TUNGETFEATURES failed: %s"
51 #define L2TPV3_BIND_FAIL "l2tpv3_open : could not bind socket err=%i"
52 #define UNIX_BIND_FAIL "unix_open : could not bind socket err=%i"
53 #define BPF_ATTACH_FAIL "Failed to attach filter size %d prog %px to %d, err %d\n"
54 #define BPF_DETACH_FAIL "Failed to detach filter size %d prog %px to %d, err %d\n"
55 
56 #define MAX_UN_LEN 107
57 
58 static const char padchar[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
59 static const char *template = "tapXXXXXX";
60 
61 /* This is very ugly and brute force lookup, but it is done
62  * only once at initialization so not worth doing hashes or
63  * anything more intelligent
64  */
65 
66 char *uml_vector_fetch_arg(struct arglist *ifspec, char *token)
67 {
68 	int i;
69 
70 	for (i = 0; i < ifspec->numargs; i++) {
71 		if (strcmp(ifspec->tokens[i], token) == 0)
72 			return ifspec->values[i];
73 	}
74 	return NULL;
75 
76 }
77 
78 struct arglist *uml_parse_vector_ifspec(char *arg)
79 {
80 	struct arglist *result;
81 	int pos, len;
82 	bool parsing_token = true, next_starts = true;
83 
84 	if (arg == NULL)
85 		return NULL;
86 	result = uml_kmalloc(sizeof(struct arglist), UM_GFP_KERNEL);
87 	if (result == NULL)
88 		return NULL;
89 	result->numargs = 0;
90 	len = strlen(arg);
91 	for (pos = 0; pos < len; pos++) {
92 		if (next_starts) {
93 			if (parsing_token) {
94 				result->tokens[result->numargs] = arg + pos;
95 			} else {
96 				result->values[result->numargs] = arg + pos;
97 				result->numargs++;
98 			}
99 			next_starts = false;
100 		}
101 		if (*(arg + pos) == '=') {
102 			if (parsing_token)
103 				parsing_token = false;
104 			else
105 				goto cleanup;
106 			next_starts = true;
107 			(*(arg + pos)) = '\0';
108 		}
109 		if (*(arg + pos) == ',') {
110 			parsing_token = true;
111 			next_starts = true;
112 			(*(arg + pos)) = '\0';
113 		}
114 	}
115 	return result;
116 cleanup:
117 	printk(UM_KERN_ERR "vector_setup - Couldn't parse '%s'\n", arg);
118 	kfree(result);
119 	return NULL;
120 }
121 
122 /*
123  * Socket/FD configuration functions. These return an structure
124  * of rx and tx descriptors to cover cases where these are not
125  * the same (f.e. read via raw socket and write via tap).
126  */
127 
128 #define PATH_NET_TUN "/dev/net/tun"
129 
130 
131 static int create_tap_fd(char *iface)
132 {
133 	struct ifreq ifr;
134 	int fd = -1;
135 	int err = -ENOMEM, offload;
136 
137 	fd = open(PATH_NET_TUN, O_RDWR);
138 	if (fd < 0) {
139 		printk(UM_KERN_ERR "uml_tap: failed to open tun device\n");
140 		goto tap_fd_cleanup;
141 	}
142 	memset(&ifr, 0, sizeof(ifr));
143 	ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR;
144 	strscpy(ifr.ifr_name, iface);
145 
146 	err = ioctl(fd, TUNSETIFF, (void *) &ifr);
147 	if (err != 0) {
148 		printk(UM_KERN_ERR "uml_tap: failed to select tap interface\n");
149 		goto tap_fd_cleanup;
150 	}
151 
152 	offload = TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6;
153 	ioctl(fd, TUNSETOFFLOAD, offload);
154 	return fd;
155 tap_fd_cleanup:
156 	if (fd >= 0)
157 		os_close_file(fd);
158 	return err;
159 }
160 
161 static int create_raw_fd(char *iface, int flags, int proto)
162 {
163 	struct ifreq ifr;
164 	int fd = -1;
165 	struct sockaddr_ll sock;
166 	int err = -ENOMEM;
167 
168 	fd = socket(AF_PACKET, SOCK_RAW, flags);
169 	if (fd == -1) {
170 		err = -errno;
171 		goto raw_fd_cleanup;
172 	}
173 	memset(&ifr, 0, sizeof(ifr));
174 	strscpy(ifr.ifr_name, iface);
175 	if (ioctl(fd, SIOCGIFINDEX, (void *) &ifr) < 0) {
176 		err = -errno;
177 		goto raw_fd_cleanup;
178 	}
179 
180 	sock.sll_family = AF_PACKET;
181 	sock.sll_protocol = htons(proto);
182 	sock.sll_ifindex = ifr.ifr_ifindex;
183 
184 	if (bind(fd,
185 		(struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
186 		err = -errno;
187 		goto raw_fd_cleanup;
188 	}
189 	return fd;
190 raw_fd_cleanup:
191 	printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err);
192 	if (fd >= 0)
193 		os_close_file(fd);
194 	return err;
195 }
196 
197 
198 static struct vector_fds *user_init_tap_fds(struct arglist *ifspec)
199 {
200 	int fd = -1, i;
201 	char *iface;
202 	struct vector_fds *result = NULL;
203 	bool dynamic = false;
204 	char dynamic_ifname[IFNAMSIZ];
205 	char *argv[] = {NULL, NULL, NULL, NULL};
206 
207 	iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME);
208 	if (iface == NULL) {
209 		dynamic = true;
210 		iface = dynamic_ifname;
211 		srand(getpid());
212 	}
213 
214 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
215 	if (result == NULL) {
216 		printk(UM_KERN_ERR "uml_tap: failed to allocate file descriptors\n");
217 		goto tap_cleanup;
218 	}
219 	result->rx_fd = -1;
220 	result->tx_fd = -1;
221 	result->remote_addr = NULL;
222 	result->remote_addr_size = 0;
223 
224 	/* TAP */
225 	do {
226 		if (dynamic) {
227 			strcpy(iface, template);
228 			for (i = 0; i < strlen(iface); i++) {
229 				if (iface[i] == 'X') {
230 					iface[i] = padchar[rand() % strlen(padchar)];
231 				}
232 			}
233 		}
234 		fd = create_tap_fd(iface);
235 		if ((fd < 0) && (!dynamic)) {
236 			printk(UM_KERN_ERR "uml_tap: failed to create tun interface\n");
237 			goto tap_cleanup;
238 		}
239 		result->tx_fd = fd;
240 		result->rx_fd = fd;
241 	} while (fd < 0);
242 
243 	argv[0] = uml_vector_fetch_arg(ifspec, TOKEN_SCRIPT);
244 	if (argv[0]) {
245 		argv[1] = iface;
246 		run_helper(NULL, NULL, argv);
247 	}
248 
249 	return result;
250 tap_cleanup:
251 	printk(UM_KERN_ERR "user_init_tap: init failed, error %d", fd);
252 	kfree(result);
253 	return NULL;
254 }
255 
256 static struct vector_fds *user_init_hybrid_fds(struct arglist *ifspec)
257 {
258 	char *iface;
259 	struct vector_fds *result = NULL;
260 	char *argv[] = {NULL, NULL, NULL, NULL};
261 
262 	iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME);
263 	if (iface == NULL) {
264 		printk(UM_KERN_ERR "uml_tap: failed to parse interface spec\n");
265 		goto hybrid_cleanup;
266 	}
267 
268 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
269 	if (result == NULL) {
270 		printk(UM_KERN_ERR "uml_tap: failed to allocate file descriptors\n");
271 		goto hybrid_cleanup;
272 	}
273 	result->rx_fd = -1;
274 	result->tx_fd = -1;
275 	result->remote_addr = NULL;
276 	result->remote_addr_size = 0;
277 
278 	/* TAP */
279 
280 	result->tx_fd = create_tap_fd(iface);
281 	if (result->tx_fd < 0) {
282 		printk(UM_KERN_ERR "uml_tap: failed to create tun interface: %i\n", result->tx_fd);
283 		goto hybrid_cleanup;
284 	}
285 
286 	/* RAW */
287 
288 	result->rx_fd = create_raw_fd(iface, ETH_P_ALL, ETH_P_ALL);
289 	if (result->rx_fd == -1) {
290 		printk(UM_KERN_ERR
291 			"uml_tap: failed to create paired raw socket: %i\n", result->rx_fd);
292 		goto hybrid_cleanup;
293 	}
294 
295 	argv[0] = uml_vector_fetch_arg(ifspec, TOKEN_SCRIPT);
296 	if (argv[0]) {
297 		argv[1] = iface;
298 		run_helper(NULL, NULL, argv);
299 	}
300 	return result;
301 hybrid_cleanup:
302 	printk(UM_KERN_ERR "user_init_hybrid: init failed");
303 	kfree(result);
304 	return NULL;
305 }
306 
307 static struct vector_fds *user_init_unix_fds(struct arglist *ifspec, int id)
308 {
309 	int fd = -1;
310 	int socktype;
311 	char *src, *dst;
312 	struct vector_fds *result = NULL;
313 	struct sockaddr_un *local_addr = NULL, *remote_addr = NULL;
314 
315 	src = uml_vector_fetch_arg(ifspec, "src");
316 	dst = uml_vector_fetch_arg(ifspec, "dst");
317 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
318 	if (result == NULL) {
319 		printk(UM_KERN_ERR "unix open:cannot allocate remote addr");
320 		goto unix_cleanup;
321 	}
322 	remote_addr = uml_kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
323 	if (remote_addr == NULL) {
324 		printk(UM_KERN_ERR "unix open:cannot allocate remote addr");
325 		goto unix_cleanup;
326 	}
327 
328 	switch (id) {
329 	case ID_BESS:
330 		socktype = SOCK_SEQPACKET;
331 		if ((src != NULL) && (strlen(src) <= MAX_UN_LEN)) {
332 			local_addr = uml_kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL);
333 			if (local_addr == NULL) {
334 				printk(UM_KERN_ERR "bess open:cannot allocate local addr");
335 				goto unix_cleanup;
336 			}
337 			local_addr->sun_family = AF_UNIX;
338 			memcpy(local_addr->sun_path, src, strlen(src) + 1);
339 		}
340 		if ((dst == NULL) || (strlen(dst) > MAX_UN_LEN))
341 			goto unix_cleanup;
342 		remote_addr->sun_family = AF_UNIX;
343 		memcpy(remote_addr->sun_path, dst, strlen(dst) + 1);
344 		break;
345 	default:
346 		printk(KERN_ERR "Unsupported unix socket type\n");
347 		return NULL;
348 	}
349 
350 	fd = socket(AF_UNIX, socktype, 0);
351 	if (fd == -1) {
352 		printk(UM_KERN_ERR
353 			"unix open: could not open socket, error = %d",
354 			-errno
355 		);
356 		goto unix_cleanup;
357 	}
358 	if (local_addr != NULL) {
359 		if (bind(fd, (struct sockaddr *) local_addr, sizeof(struct sockaddr_un))) {
360 			printk(UM_KERN_ERR UNIX_BIND_FAIL, errno);
361 			goto unix_cleanup;
362 		}
363 	}
364 	switch (id) {
365 	case ID_BESS:
366 		if (connect(fd, (const struct sockaddr *) remote_addr, sizeof(struct sockaddr_un)) < 0) {
367 			printk(UM_KERN_ERR "bess open:cannot connect to %s %i", remote_addr->sun_path, -errno);
368 			goto unix_cleanup;
369 		}
370 		break;
371 	}
372 	result->rx_fd = fd;
373 	result->tx_fd = fd;
374 	result->remote_addr_size = sizeof(struct sockaddr_un);
375 	result->remote_addr = remote_addr;
376 	return result;
377 unix_cleanup:
378 	if (fd >= 0)
379 		os_close_file(fd);
380 	kfree(remote_addr);
381 	kfree(result);
382 	return NULL;
383 }
384 
385 static int strtofd(const char *nptr)
386 {
387 	long fd;
388 	char *endptr;
389 
390 	if (nptr == NULL)
391 		return -1;
392 
393 	errno = 0;
394 	fd = strtol(nptr, &endptr, 10);
395 	if (nptr == endptr ||
396 		errno != 0 ||
397 		*endptr != '\0' ||
398 		fd < 0 ||
399 		fd > INT_MAX) {
400 		return -1;
401 	}
402 	return fd;
403 }
404 
405 static struct vector_fds *user_init_fd_fds(struct arglist *ifspec)
406 {
407 	int fd = -1;
408 	char *fdarg = NULL;
409 	struct vector_fds *result = NULL;
410 
411 	fdarg = uml_vector_fetch_arg(ifspec, "fd");
412 	fd = strtofd(fdarg);
413 	if (fd == -1) {
414 		printk(UM_KERN_ERR "fd open: bad or missing fd argument");
415 		goto fd_cleanup;
416 	}
417 
418 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
419 	if (result == NULL) {
420 		printk(UM_KERN_ERR "fd open: allocation failed");
421 		goto fd_cleanup;
422 	}
423 
424 	result->rx_fd = fd;
425 	result->tx_fd = fd;
426 	result->remote_addr_size = 0;
427 	result->remote_addr = NULL;
428 	return result;
429 
430 fd_cleanup:
431 	if (fd >= 0)
432 		os_close_file(fd);
433 	kfree(result);
434 	return NULL;
435 }
436 
437 static struct vector_fds *user_init_raw_fds(struct arglist *ifspec)
438 {
439 	int rxfd = -1, txfd = -1;
440 	int err = -ENOMEM;
441 	char *iface;
442 	struct vector_fds *result = NULL;
443 	char *argv[] = {NULL, NULL, NULL, NULL};
444 
445 	iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME);
446 	if (iface == NULL)
447 		goto raw_cleanup;
448 
449 	rxfd = create_raw_fd(iface, ETH_P_ALL, ETH_P_ALL);
450 	if (rxfd == -1) {
451 		err = -errno;
452 		goto raw_cleanup;
453 	}
454 	txfd = create_raw_fd(iface, 0, ETH_P_IP); /* Turn off RX on this fd */
455 	if (txfd == -1) {
456 		err = -errno;
457 		goto raw_cleanup;
458 	}
459 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
460 	if (result != NULL) {
461 		result->rx_fd = rxfd;
462 		result->tx_fd = txfd;
463 		result->remote_addr = NULL;
464 		result->remote_addr_size = 0;
465 	}
466 	argv[0] = uml_vector_fetch_arg(ifspec, TOKEN_SCRIPT);
467 	if (argv[0]) {
468 		argv[1] = iface;
469 		run_helper(NULL, NULL, argv);
470 	}
471 	return result;
472 raw_cleanup:
473 	printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err);
474 	kfree(result);
475 	return NULL;
476 }
477 
478 
479 bool uml_raw_enable_qdisc_bypass(int fd)
480 {
481 	int optval = 1;
482 
483 	if (setsockopt(fd,
484 		SOL_PACKET, PACKET_QDISC_BYPASS,
485 		&optval, sizeof(optval)) != 0) {
486 		return false;
487 	}
488 	return true;
489 }
490 
491 bool uml_raw_enable_vnet_headers(int fd)
492 {
493 	int optval = 1;
494 
495 	if (setsockopt(fd,
496 		SOL_PACKET, PACKET_VNET_HDR,
497 		&optval, sizeof(optval)) != 0) {
498 		printk(UM_KERN_INFO VNET_HDR_FAIL, fd);
499 		return false;
500 	}
501 	return true;
502 }
503 bool uml_tap_enable_vnet_headers(int fd)
504 {
505 	unsigned int features;
506 	int len = sizeof(struct virtio_net_hdr);
507 
508 	if (ioctl(fd, TUNGETFEATURES, &features) == -1) {
509 		printk(UM_KERN_INFO TUN_GET_F_FAIL, strerror(errno));
510 		return false;
511 	}
512 	if ((features & IFF_VNET_HDR) == 0) {
513 		printk(UM_KERN_INFO "tapraw: No VNET HEADER support");
514 		return false;
515 	}
516 	ioctl(fd, TUNSETVNETHDRSZ, &len);
517 	return true;
518 }
519 
520 static struct vector_fds *user_init_socket_fds(struct arglist *ifspec, int id)
521 {
522 	int err = -ENOMEM;
523 	int fd = -1, gairet;
524 	struct addrinfo srchints;
525 	struct addrinfo dsthints;
526 	bool v6, udp;
527 	char *value;
528 	char *src, *dst, *srcport, *dstport;
529 	struct addrinfo *gairesult = NULL;
530 	struct vector_fds *result = NULL;
531 
532 
533 	value = uml_vector_fetch_arg(ifspec, "v6");
534 	v6 = false;
535 	udp = false;
536 	if (value != NULL) {
537 		if (strtol((const char *) value, NULL, 10) > 0)
538 			v6 = true;
539 	}
540 
541 	value = uml_vector_fetch_arg(ifspec, "udp");
542 	if (value != NULL) {
543 		if (strtol((const char *) value, NULL, 10) > 0)
544 			udp = true;
545 	}
546 	src = uml_vector_fetch_arg(ifspec, "src");
547 	dst = uml_vector_fetch_arg(ifspec, "dst");
548 	srcport = uml_vector_fetch_arg(ifspec, "srcport");
549 	dstport = uml_vector_fetch_arg(ifspec, "dstport");
550 
551 	memset(&dsthints, 0, sizeof(dsthints));
552 
553 	if (v6)
554 		dsthints.ai_family = AF_INET6;
555 	else
556 		dsthints.ai_family = AF_INET;
557 
558 	switch (id) {
559 	case ID_GRE:
560 		dsthints.ai_socktype = SOCK_RAW;
561 		dsthints.ai_protocol = IPPROTO_GRE;
562 		break;
563 	case ID_L2TPV3:
564 		if (udp) {
565 			dsthints.ai_socktype = SOCK_DGRAM;
566 			dsthints.ai_protocol = 0;
567 		} else {
568 			dsthints.ai_socktype = SOCK_RAW;
569 			dsthints.ai_protocol = IPPROTO_L2TP;
570 		}
571 		break;
572 	default:
573 		printk(KERN_ERR "Unsupported socket type\n");
574 		return NULL;
575 	}
576 	memcpy(&srchints, &dsthints, sizeof(struct addrinfo));
577 
578 	gairet = getaddrinfo(src, srcport, &dsthints, &gairesult);
579 	if ((gairet != 0) || (gairesult == NULL)) {
580 		printk(UM_KERN_ERR
581 			"socket_open : could not resolve src, error = %s",
582 			gai_strerror(gairet)
583 		);
584 		return NULL;
585 	}
586 	fd = socket(gairesult->ai_family,
587 		gairesult->ai_socktype, gairesult->ai_protocol);
588 	if (fd == -1) {
589 		printk(UM_KERN_ERR
590 			"socket_open : could not open socket, error = %d",
591 			-errno
592 		);
593 		goto cleanup;
594 	}
595 	if (bind(fd,
596 		(struct sockaddr *) gairesult->ai_addr,
597 		gairesult->ai_addrlen)) {
598 		printk(UM_KERN_ERR L2TPV3_BIND_FAIL, errno);
599 		goto cleanup;
600 	}
601 
602 	if (gairesult != NULL)
603 		freeaddrinfo(gairesult);
604 
605 	gairesult = NULL;
606 
607 	gairet = getaddrinfo(dst, dstport, &dsthints, &gairesult);
608 	if ((gairet != 0) || (gairesult == NULL)) {
609 		printk(UM_KERN_ERR
610 			"socket_open : could not resolve dst, error = %s",
611 			gai_strerror(gairet)
612 		);
613 		return NULL;
614 	}
615 
616 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
617 	if (result != NULL) {
618 		result->rx_fd = fd;
619 		result->tx_fd = fd;
620 		result->remote_addr = uml_kmalloc(
621 			gairesult->ai_addrlen, UM_GFP_KERNEL);
622 		if (result->remote_addr == NULL)
623 			goto cleanup;
624 		result->remote_addr_size = gairesult->ai_addrlen;
625 		memcpy(
626 			result->remote_addr,
627 			gairesult->ai_addr,
628 			gairesult->ai_addrlen
629 		);
630 	}
631 	freeaddrinfo(gairesult);
632 	return result;
633 cleanup:
634 	if (gairesult != NULL)
635 		freeaddrinfo(gairesult);
636 	printk(UM_KERN_ERR "user_init_socket: init failed, error %d", err);
637 	if (fd >= 0)
638 		os_close_file(fd);
639 	if (result != NULL) {
640 		kfree(result->remote_addr);
641 		kfree(result);
642 	}
643 	return NULL;
644 }
645 
646 struct vector_fds *uml_vector_user_open(
647 	int unit,
648 	struct arglist *parsed
649 )
650 {
651 	char *transport;
652 
653 	if (parsed == NULL) {
654 		printk(UM_KERN_ERR "no parsed config for unit %d\n", unit);
655 		return NULL;
656 	}
657 	transport = uml_vector_fetch_arg(parsed, "transport");
658 	if (transport == NULL) {
659 		printk(UM_KERN_ERR "missing transport for unit %d\n", unit);
660 		return NULL;
661 	}
662 	if (strncmp(transport, TRANS_RAW, TRANS_RAW_LEN) == 0)
663 		return user_init_raw_fds(parsed);
664 	if (strncmp(transport, TRANS_HYBRID, TRANS_HYBRID_LEN) == 0)
665 		return user_init_hybrid_fds(parsed);
666 	if (strncmp(transport, TRANS_TAP, TRANS_TAP_LEN) == 0)
667 		return user_init_tap_fds(parsed);
668 	if (strncmp(transport, TRANS_GRE, TRANS_GRE_LEN) == 0)
669 		return user_init_socket_fds(parsed, ID_GRE);
670 	if (strncmp(transport, TRANS_L2TPV3, TRANS_L2TPV3_LEN) == 0)
671 		return user_init_socket_fds(parsed, ID_L2TPV3);
672 	if (strncmp(transport, TRANS_BESS, TRANS_BESS_LEN) == 0)
673 		return user_init_unix_fds(parsed, ID_BESS);
674 	if (strncmp(transport, TRANS_FD, TRANS_FD_LEN) == 0)
675 		return user_init_fd_fds(parsed);
676 	return NULL;
677 }
678 
679 
680 int uml_vector_sendmsg(int fd, void *hdr, int flags)
681 {
682 	int n;
683 
684 	CATCH_EINTR(n = sendmsg(fd, (struct msghdr *) hdr,  flags));
685 	if ((n < 0) && (errno == EAGAIN))
686 		return 0;
687 	if (n >= 0)
688 		return n;
689 	else
690 		return -errno;
691 }
692 
693 int uml_vector_recvmsg(int fd, void *hdr, int flags)
694 {
695 	int n;
696 	struct msghdr *msg = (struct msghdr *) hdr;
697 
698 	CATCH_EINTR(n = readv(fd, msg->msg_iov, msg->msg_iovlen));
699 	if ((n < 0) && (errno == EAGAIN))
700 		return 0;
701 	if (n >= 0)
702 		return n;
703 	else
704 		return -errno;
705 }
706 
707 int uml_vector_writev(int fd, void *hdr, int iovcount)
708 {
709 	int n;
710 
711 	CATCH_EINTR(n = writev(fd, (struct iovec *) hdr,  iovcount));
712 	if ((n < 0) && ((errno == EAGAIN) || (errno == ENOBUFS)))
713 		return 0;
714 	if (n >= 0)
715 		return n;
716 	else
717 		return -errno;
718 }
719 
720 int uml_vector_sendmmsg(
721 	int fd,
722 	void *msgvec,
723 	unsigned int vlen,
724 	unsigned int flags)
725 {
726 	int n;
727 
728 	CATCH_EINTR(n = sendmmsg(fd, (struct mmsghdr *) msgvec, vlen, flags));
729 	if ((n < 0) && ((errno == EAGAIN) || (errno == ENOBUFS)))
730 		return 0;
731 	if (n >= 0)
732 		return n;
733 	else
734 		return -errno;
735 }
736 
737 int uml_vector_recvmmsg(
738 	int fd,
739 	void *msgvec,
740 	unsigned int vlen,
741 	unsigned int flags)
742 {
743 	int n;
744 
745 	CATCH_EINTR(
746 		n = recvmmsg(fd, (struct mmsghdr *) msgvec, vlen, flags, 0));
747 	if ((n < 0) && (errno == EAGAIN))
748 		return 0;
749 	if (n >= 0)
750 		return n;
751 	else
752 		return -errno;
753 }
754 int uml_vector_attach_bpf(int fd, void *bpf)
755 {
756 	struct sock_fprog *prog = bpf;
757 
758 	int err = setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, bpf, sizeof(struct sock_fprog));
759 
760 	if (err < 0)
761 		printk(KERN_ERR BPF_ATTACH_FAIL, prog->len, prog->filter, fd, -errno);
762 	return err;
763 }
764 
765 int uml_vector_detach_bpf(int fd, void *bpf)
766 {
767 	struct sock_fprog *prog = bpf;
768 
769 	int err = setsockopt(fd, SOL_SOCKET, SO_DETACH_FILTER, bpf, sizeof(struct sock_fprog));
770 	if (err < 0)
771 		printk(KERN_ERR BPF_DETACH_FAIL, prog->len, prog->filter, fd, -errno);
772 	return err;
773 }
774 void *uml_vector_default_bpf(const void *mac)
775 {
776 	struct sock_filter *bpf;
777 	uint32_t *mac1 = (uint32_t *)(mac + 2);
778 	uint16_t *mac2 = (uint16_t *) mac;
779 	struct sock_fprog *bpf_prog;
780 
781 	bpf_prog = uml_kmalloc(sizeof(struct sock_fprog), UM_GFP_KERNEL);
782 	if (bpf_prog) {
783 		bpf_prog->len = DEFAULT_BPF_LEN;
784 		bpf_prog->filter = NULL;
785 	} else {
786 		return NULL;
787 	}
788 	bpf = uml_kmalloc(
789 		sizeof(struct sock_filter) * DEFAULT_BPF_LEN, UM_GFP_KERNEL);
790 	if (bpf) {
791 		bpf_prog->filter = bpf;
792 		/* ld	[8] */
793 		bpf[0] = (struct sock_filter){ 0x20, 0, 0, 0x00000008 };
794 		/* jeq	#0xMAC[2-6] jt 2 jf 5*/
795 		bpf[1] = (struct sock_filter){ 0x15, 0, 3, ntohl(*mac1)};
796 		/* ldh	[6] */
797 		bpf[2] = (struct sock_filter){ 0x28, 0, 0, 0x00000006 };
798 		/* jeq	#0xMAC[0-1] jt 4 jf 5 */
799 		bpf[3] = (struct sock_filter){ 0x15, 0, 1, ntohs(*mac2)};
800 		/* ret	#0 */
801 		bpf[4] = (struct sock_filter){ 0x6, 0, 0, 0x00000000 };
802 		/* ret	#0x40000 */
803 		bpf[5] = (struct sock_filter){ 0x6, 0, 0, 0x00040000 };
804 	} else {
805 		kfree(bpf_prog);
806 		bpf_prog = NULL;
807 	}
808 	return bpf_prog;
809 }
810 
811 /* Note - this function requires a valid mac being passed as an arg */
812 
813 void *uml_vector_user_bpf(char *filename)
814 {
815 	struct sock_filter *bpf;
816 	struct sock_fprog *bpf_prog;
817 	struct stat statbuf;
818 	int res, ffd = -1;
819 
820 	if (filename == NULL)
821 		return NULL;
822 
823 	if (stat(filename, &statbuf) < 0) {
824 		printk(KERN_ERR "Error %d reading bpf file", -errno);
825 		return false;
826 	}
827 	bpf_prog = uml_kmalloc(sizeof(struct sock_fprog), UM_GFP_KERNEL);
828 	if (bpf_prog == NULL) {
829 		printk(KERN_ERR "Failed to allocate bpf prog buffer");
830 		return NULL;
831 	}
832 	bpf_prog->len = statbuf.st_size / sizeof(struct sock_filter);
833 	bpf_prog->filter = NULL;
834 	ffd = os_open_file(filename, of_read(OPENFLAGS()), 0);
835 	if (ffd < 0) {
836 		printk(KERN_ERR "Error %d opening bpf file", -errno);
837 		goto bpf_failed;
838 	}
839 	bpf = uml_kmalloc(statbuf.st_size, UM_GFP_KERNEL);
840 	if (bpf == NULL) {
841 		printk(KERN_ERR "Failed to allocate bpf buffer");
842 		goto bpf_failed;
843 	}
844 	bpf_prog->filter = bpf;
845 	res = os_read_file(ffd, bpf, statbuf.st_size);
846 	if (res < statbuf.st_size) {
847 		printk(KERN_ERR "Failed to read bpf program %s, error %d", filename, res);
848 		kfree(bpf);
849 		goto bpf_failed;
850 	}
851 	os_close_file(ffd);
852 	return bpf_prog;
853 bpf_failed:
854 	if (ffd > 0)
855 		os_close_file(ffd);
856 	kfree(bpf_prog);
857 	return NULL;
858 }
859