xref: /openbmc/linux/arch/um/drivers/vector_user.c (revision 3213486f)
1 /*
2  * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3  * Licensed under the GPL
4  */
5 
6 #include <stdio.h>
7 #include <unistd.h>
8 #include <stdarg.h>
9 #include <errno.h>
10 #include <stddef.h>
11 #include <string.h>
12 #include <sys/ioctl.h>
13 #include <net/if.h>
14 #include <linux/if_tun.h>
15 #include <arpa/inet.h>
16 #include <sys/types.h>
17 #include <sys/stat.h>
18 #include <fcntl.h>
19 #include <sys/socket.h>
20 #include <net/ethernet.h>
21 #include <netinet/ip.h>
22 #include <netinet/ether.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 <um_malloc.h>
32 #include "vector_user.h"
33 
34 #define ID_GRE 0
35 #define ID_L2TPV3 1
36 #define ID_MAX 1
37 
38 #define TOKEN_IFNAME "ifname"
39 
40 #define TRANS_RAW "raw"
41 #define TRANS_RAW_LEN strlen(TRANS_RAW)
42 
43 #define VNET_HDR_FAIL "could not enable vnet headers on fd %d"
44 #define TUN_GET_F_FAIL "tapraw: TUNGETFEATURES failed: %s"
45 #define L2TPV3_BIND_FAIL "l2tpv3_open : could not bind socket err=%i"
46 #define BPF_ATTACH_FAIL "Failed to attach filter size %d to %d, err %d\n"
47 
48 /* This is very ugly and brute force lookup, but it is done
49  * only once at initialization so not worth doing hashes or
50  * anything more intelligent
51  */
52 
53 char *uml_vector_fetch_arg(struct arglist *ifspec, char *token)
54 {
55 	int i;
56 
57 	for (i = 0; i < ifspec->numargs; i++) {
58 		if (strcmp(ifspec->tokens[i], token) == 0)
59 			return ifspec->values[i];
60 	}
61 	return NULL;
62 
63 }
64 
65 struct arglist *uml_parse_vector_ifspec(char *arg)
66 {
67 	struct arglist *result;
68 	int pos, len;
69 	bool parsing_token = true, next_starts = true;
70 
71 	if (arg == NULL)
72 		return NULL;
73 	result = uml_kmalloc(sizeof(struct arglist), UM_GFP_KERNEL);
74 	if (result == NULL)
75 		return NULL;
76 	result->numargs = 0;
77 	len = strlen(arg);
78 	for (pos = 0; pos < len; pos++) {
79 		if (next_starts) {
80 			if (parsing_token) {
81 				result->tokens[result->numargs] = arg + pos;
82 			} else {
83 				result->values[result->numargs] = arg + pos;
84 				result->numargs++;
85 			}
86 			next_starts = false;
87 		}
88 		if (*(arg + pos) == '=') {
89 			if (parsing_token)
90 				parsing_token = false;
91 			else
92 				goto cleanup;
93 			next_starts = true;
94 			(*(arg + pos)) = '\0';
95 		}
96 		if (*(arg + pos) == ',') {
97 			parsing_token = true;
98 			next_starts = true;
99 			(*(arg + pos)) = '\0';
100 		}
101 	}
102 	return result;
103 cleanup:
104 	printk(UM_KERN_ERR "vector_setup - Couldn't parse '%s'\n", arg);
105 	kfree(result);
106 	return NULL;
107 }
108 
109 /*
110  * Socket/FD configuration functions. These return an structure
111  * of rx and tx descriptors to cover cases where these are not
112  * the same (f.e. read via raw socket and write via tap).
113  */
114 
115 #define PATH_NET_TUN "/dev/net/tun"
116 
117 static struct vector_fds *user_init_tap_fds(struct arglist *ifspec)
118 {
119 	struct ifreq ifr;
120 	int fd = -1;
121 	struct sockaddr_ll sock;
122 	int err = -ENOMEM, offload;
123 	char *iface;
124 	struct vector_fds *result = NULL;
125 
126 	iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME);
127 	if (iface == NULL) {
128 		printk(UM_KERN_ERR "uml_tap: failed to parse interface spec\n");
129 		goto tap_cleanup;
130 	}
131 
132 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
133 	if (result == NULL) {
134 		printk(UM_KERN_ERR "uml_tap: failed to allocate file descriptors\n");
135 		goto tap_cleanup;
136 	}
137 	result->rx_fd = -1;
138 	result->tx_fd = -1;
139 	result->remote_addr = NULL;
140 	result->remote_addr_size = 0;
141 
142 	/* TAP */
143 
144 	fd = open(PATH_NET_TUN, O_RDWR);
145 	if (fd < 0) {
146 		printk(UM_KERN_ERR "uml_tap: failed to open tun device\n");
147 		goto tap_cleanup;
148 	}
149 	result->tx_fd = fd;
150 	memset(&ifr, 0, sizeof(ifr));
151 	ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR;
152 	strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
153 
154 	err = ioctl(fd, TUNSETIFF, (void *) &ifr);
155 	if (err != 0) {
156 		printk(UM_KERN_ERR "uml_tap: failed to select tap interface\n");
157 		goto tap_cleanup;
158 	}
159 
160 	offload = TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6;
161 	ioctl(fd, TUNSETOFFLOAD, offload);
162 
163 	/* RAW */
164 
165 	fd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
166 	if (fd == -1) {
167 		printk(UM_KERN_ERR
168 			"uml_tap: failed to create socket: %i\n", -errno);
169 		goto tap_cleanup;
170 	}
171 	result->rx_fd = fd;
172 	memset(&ifr, 0, sizeof(ifr));
173 	strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
174 	if (ioctl(fd, SIOCGIFINDEX, (void *) &ifr) < 0) {
175 		printk(UM_KERN_ERR
176 			"uml_tap: failed to set interface: %i\n", -errno);
177 		goto tap_cleanup;
178 	}
179 
180 	sock.sll_family = AF_PACKET;
181 	sock.sll_protocol = htons(ETH_P_ALL);
182 	sock.sll_ifindex = ifr.ifr_ifindex;
183 
184 	if (bind(fd,
185 		(struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
186 		printk(UM_KERN_ERR
187 			"user_init_tap: failed to bind raw pair, err %d\n",
188 				-errno);
189 		goto tap_cleanup;
190 	}
191 	return result;
192 tap_cleanup:
193 	printk(UM_KERN_ERR "user_init_tap: init failed, error %d", err);
194 	if (result != NULL) {
195 		if (result->rx_fd >= 0)
196 			os_close_file(result->rx_fd);
197 		if (result->tx_fd >= 0)
198 			os_close_file(result->tx_fd);
199 		kfree(result);
200 	}
201 	return NULL;
202 }
203 
204 
205 static struct vector_fds *user_init_raw_fds(struct arglist *ifspec)
206 {
207 	struct ifreq ifr;
208 	int rxfd = -1, txfd = -1;
209 	struct sockaddr_ll sock;
210 	int err = -ENOMEM;
211 	char *iface;
212 	struct vector_fds *result = NULL;
213 
214 	iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME);
215 	if (iface == NULL)
216 		goto cleanup;
217 
218 	rxfd = socket(AF_PACKET, SOCK_RAW, ETH_P_ALL);
219 	if (rxfd == -1) {
220 		err = -errno;
221 		goto cleanup;
222 	}
223 	txfd = socket(AF_PACKET, SOCK_RAW, 0); /* Turn off RX on this fd */
224 	if (txfd == -1) {
225 		err = -errno;
226 		goto cleanup;
227 	}
228 	memset(&ifr, 0, sizeof(ifr));
229 	strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
230 	if (ioctl(rxfd, SIOCGIFINDEX, (void *) &ifr) < 0) {
231 		err = -errno;
232 		goto cleanup;
233 	}
234 
235 	sock.sll_family = AF_PACKET;
236 	sock.sll_protocol = htons(ETH_P_ALL);
237 	sock.sll_ifindex = ifr.ifr_ifindex;
238 
239 	if (bind(rxfd,
240 		(struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
241 		err = -errno;
242 		goto cleanup;
243 	}
244 
245 	sock.sll_family = AF_PACKET;
246 	sock.sll_protocol = htons(ETH_P_IP);
247 	sock.sll_ifindex = ifr.ifr_ifindex;
248 
249 	if (bind(txfd,
250 		(struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
251 		err = -errno;
252 		goto cleanup;
253 	}
254 
255 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
256 	if (result != NULL) {
257 		result->rx_fd = rxfd;
258 		result->tx_fd = txfd;
259 		result->remote_addr = NULL;
260 		result->remote_addr_size = 0;
261 	}
262 	return result;
263 cleanup:
264 	printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err);
265 	if (rxfd >= 0)
266 		os_close_file(rxfd);
267 	if (txfd >= 0)
268 		os_close_file(txfd);
269 	kfree(result);
270 	return NULL;
271 }
272 
273 
274 bool uml_raw_enable_qdisc_bypass(int fd)
275 {
276 	int optval = 1;
277 
278 	if (setsockopt(fd,
279 		SOL_PACKET, PACKET_QDISC_BYPASS,
280 		&optval, sizeof(optval)) != 0) {
281 		return false;
282 	}
283 	return true;
284 }
285 
286 bool uml_raw_enable_vnet_headers(int fd)
287 {
288 	int optval = 1;
289 
290 	if (setsockopt(fd,
291 		SOL_PACKET, PACKET_VNET_HDR,
292 		&optval, sizeof(optval)) != 0) {
293 		printk(UM_KERN_INFO VNET_HDR_FAIL, fd);
294 		return false;
295 	}
296 	return true;
297 }
298 bool uml_tap_enable_vnet_headers(int fd)
299 {
300 	unsigned int features;
301 	int len = sizeof(struct virtio_net_hdr);
302 
303 	if (ioctl(fd, TUNGETFEATURES, &features) == -1) {
304 		printk(UM_KERN_INFO TUN_GET_F_FAIL, strerror(errno));
305 		return false;
306 	}
307 	if ((features & IFF_VNET_HDR) == 0) {
308 		printk(UM_KERN_INFO "tapraw: No VNET HEADER support");
309 		return false;
310 	}
311 	ioctl(fd, TUNSETVNETHDRSZ, &len);
312 	return true;
313 }
314 
315 static struct vector_fds *user_init_socket_fds(struct arglist *ifspec, int id)
316 {
317 	int err = -ENOMEM;
318 	int fd = -1, gairet;
319 	struct addrinfo srchints;
320 	struct addrinfo dsthints;
321 	bool v6, udp;
322 	char *value;
323 	char *src, *dst, *srcport, *dstport;
324 	struct addrinfo *gairesult = NULL;
325 	struct vector_fds *result = NULL;
326 
327 
328 	value = uml_vector_fetch_arg(ifspec, "v6");
329 	v6 = false;
330 	udp = false;
331 	if (value != NULL) {
332 		if (strtol((const char *) value, NULL, 10) > 0)
333 			v6 = true;
334 	}
335 
336 	value = uml_vector_fetch_arg(ifspec, "udp");
337 	if (value != NULL) {
338 		if (strtol((const char *) value, NULL, 10) > 0)
339 			udp = true;
340 	}
341 	src = uml_vector_fetch_arg(ifspec, "src");
342 	dst = uml_vector_fetch_arg(ifspec, "dst");
343 	srcport = uml_vector_fetch_arg(ifspec, "srcport");
344 	dstport = uml_vector_fetch_arg(ifspec, "dstport");
345 
346 	memset(&dsthints, 0, sizeof(dsthints));
347 
348 	if (v6)
349 		dsthints.ai_family = AF_INET6;
350 	else
351 		dsthints.ai_family = AF_INET;
352 
353 	switch (id) {
354 	case ID_GRE:
355 		dsthints.ai_socktype = SOCK_RAW;
356 		dsthints.ai_protocol = IPPROTO_GRE;
357 		break;
358 	case ID_L2TPV3:
359 		if (udp) {
360 			dsthints.ai_socktype = SOCK_DGRAM;
361 			dsthints.ai_protocol = 0;
362 		} else {
363 			dsthints.ai_socktype = SOCK_RAW;
364 			dsthints.ai_protocol = IPPROTO_L2TP;
365 		}
366 		break;
367 	default:
368 		printk(KERN_ERR "Unsupported socket type\n");
369 		return NULL;
370 	}
371 	memcpy(&srchints, &dsthints, sizeof(struct addrinfo));
372 
373 	gairet = getaddrinfo(src, srcport, &dsthints, &gairesult);
374 	if ((gairet != 0) || (gairesult == NULL)) {
375 		printk(UM_KERN_ERR
376 			"socket_open : could not resolve src, error = %s",
377 			gai_strerror(gairet)
378 		);
379 		return NULL;
380 	}
381 	fd = socket(gairesult->ai_family,
382 		gairesult->ai_socktype, gairesult->ai_protocol);
383 	if (fd == -1) {
384 		printk(UM_KERN_ERR
385 			"socket_open : could not open socket, error = %d",
386 			-errno
387 		);
388 		goto cleanup;
389 	}
390 	if (bind(fd,
391 		(struct sockaddr *) gairesult->ai_addr,
392 		gairesult->ai_addrlen)) {
393 		printk(UM_KERN_ERR L2TPV3_BIND_FAIL, errno);
394 		goto cleanup;
395 	}
396 
397 	if (gairesult != NULL)
398 		freeaddrinfo(gairesult);
399 
400 	gairesult = NULL;
401 
402 	gairet = getaddrinfo(dst, dstport, &dsthints, &gairesult);
403 	if ((gairet != 0) || (gairesult == NULL)) {
404 		printk(UM_KERN_ERR
405 			"socket_open : could not resolve dst, error = %s",
406 			gai_strerror(gairet)
407 		);
408 		return NULL;
409 	}
410 
411 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
412 	if (result != NULL) {
413 		result->rx_fd = fd;
414 		result->tx_fd = fd;
415 		result->remote_addr = uml_kmalloc(
416 			gairesult->ai_addrlen, UM_GFP_KERNEL);
417 		if (result->remote_addr == NULL)
418 			goto cleanup;
419 		result->remote_addr_size = gairesult->ai_addrlen;
420 		memcpy(
421 			result->remote_addr,
422 			gairesult->ai_addr,
423 			gairesult->ai_addrlen
424 		);
425 	}
426 	freeaddrinfo(gairesult);
427 	return result;
428 cleanup:
429 	if (gairesult != NULL)
430 		freeaddrinfo(gairesult);
431 	printk(UM_KERN_ERR "user_init_socket: init failed, error %d", err);
432 	if (fd >= 0)
433 		os_close_file(fd);
434 	if (result != NULL) {
435 		kfree(result->remote_addr);
436 		kfree(result);
437 	}
438 	return NULL;
439 }
440 
441 struct vector_fds *uml_vector_user_open(
442 	int unit,
443 	struct arglist *parsed
444 )
445 {
446 	char *transport;
447 
448 	if (parsed == NULL) {
449 		printk(UM_KERN_ERR "no parsed config for unit %d\n", unit);
450 		return NULL;
451 	}
452 	transport = uml_vector_fetch_arg(parsed, "transport");
453 	if (transport == NULL) {
454 		printk(UM_KERN_ERR "missing transport for unit %d\n", unit);
455 		return NULL;
456 	}
457 	if (strncmp(transport, TRANS_RAW, TRANS_RAW_LEN) == 0)
458 		return user_init_raw_fds(parsed);
459 	if (strncmp(transport, TRANS_TAP, TRANS_TAP_LEN) == 0)
460 		return user_init_tap_fds(parsed);
461 	if (strncmp(transport, TRANS_GRE, TRANS_GRE_LEN) == 0)
462 		return user_init_socket_fds(parsed, ID_GRE);
463 	if (strncmp(transport, TRANS_L2TPV3, TRANS_L2TPV3_LEN) == 0)
464 		return user_init_socket_fds(parsed, ID_L2TPV3);
465 	return NULL;
466 }
467 
468 
469 int uml_vector_sendmsg(int fd, void *hdr, int flags)
470 {
471 	int n;
472 
473 	CATCH_EINTR(n = sendmsg(fd, (struct msghdr *) hdr,  flags));
474 	if ((n < 0) && (errno == EAGAIN))
475 		return 0;
476 	if (n >= 0)
477 		return n;
478 	else
479 		return -errno;
480 }
481 
482 int uml_vector_recvmsg(int fd, void *hdr, int flags)
483 {
484 	int n;
485 
486 	CATCH_EINTR(n = recvmsg(fd, (struct msghdr *) hdr,  flags));
487 	if ((n < 0) && (errno == EAGAIN))
488 		return 0;
489 	if (n >= 0)
490 		return n;
491 	else
492 		return -errno;
493 }
494 
495 int uml_vector_writev(int fd, void *hdr, int iovcount)
496 {
497 	int n;
498 
499 	CATCH_EINTR(n = writev(fd, (struct iovec *) hdr,  iovcount));
500 	if ((n < 0) && (errno == EAGAIN))
501 		return 0;
502 	if (n >= 0)
503 		return n;
504 	else
505 		return -errno;
506 }
507 
508 int uml_vector_sendmmsg(
509 	int fd,
510 	void *msgvec,
511 	unsigned int vlen,
512 	unsigned int flags)
513 {
514 	int n;
515 
516 	CATCH_EINTR(n = sendmmsg(fd, (struct mmsghdr *) msgvec, vlen, flags));
517 	if ((n < 0) && (errno == EAGAIN))
518 		return 0;
519 	if (n >= 0)
520 		return n;
521 	else
522 		return -errno;
523 }
524 
525 int uml_vector_recvmmsg(
526 	int fd,
527 	void *msgvec,
528 	unsigned int vlen,
529 	unsigned int flags)
530 {
531 	int n;
532 
533 	CATCH_EINTR(
534 		n = recvmmsg(fd, (struct mmsghdr *) msgvec, vlen, flags, 0));
535 	if ((n < 0) && (errno == EAGAIN))
536 		return 0;
537 	if (n >= 0)
538 		return n;
539 	else
540 		return -errno;
541 }
542 int uml_vector_attach_bpf(int fd, void *bpf, int bpf_len)
543 {
544 	int err = setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, bpf, bpf_len);
545 
546 	if (err < 0)
547 		printk(KERN_ERR BPF_ATTACH_FAIL, bpf_len, fd, -errno);
548 	return err;
549 }
550 
551 #define DEFAULT_BPF_LEN 6
552 
553 void *uml_vector_default_bpf(int fd, void *mac)
554 {
555 	struct sock_filter *bpf;
556 	uint32_t *mac1 = (uint32_t *)(mac + 2);
557 	uint16_t *mac2 = (uint16_t *) mac;
558 	struct sock_fprog bpf_prog = {
559 		.len = 6,
560 		.filter = NULL,
561 	};
562 
563 	bpf = uml_kmalloc(
564 		sizeof(struct sock_filter) * DEFAULT_BPF_LEN, UM_GFP_KERNEL);
565 	if (bpf != NULL) {
566 		bpf_prog.filter = bpf;
567 		/* ld	[8] */
568 		bpf[0] = (struct sock_filter){ 0x20, 0, 0, 0x00000008 };
569 		/* jeq	#0xMAC[2-6] jt 2 jf 5*/
570 		bpf[1] = (struct sock_filter){ 0x15, 0, 3, ntohl(*mac1)};
571 		/* ldh	[6] */
572 		bpf[2] = (struct sock_filter){ 0x28, 0, 0, 0x00000006 };
573 		/* jeq	#0xMAC[0-1] jt 4 jf 5 */
574 		bpf[3] = (struct sock_filter){ 0x15, 0, 1, ntohs(*mac2)};
575 		/* ret	#0 */
576 		bpf[4] = (struct sock_filter){ 0x6, 0, 0, 0x00000000 };
577 		/* ret	#0x40000 */
578 		bpf[5] = (struct sock_filter){ 0x6, 0, 0, 0x00040000 };
579 		if (uml_vector_attach_bpf(
580 			fd, &bpf_prog, sizeof(struct sock_fprog)) < 0) {
581 			kfree(bpf);
582 			bpf = NULL;
583 		}
584 	}
585 	return bpf;
586 }
587 
588