xref: /openbmc/linux/arch/um/drivers/vector_user.c (revision 4cff79e9)
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/types.h>
20 #include <sys/socket.h>
21 #include <net/ethernet.h>
22 #include <netinet/ip.h>
23 #include <netinet/ether.h>
24 #include <linux/if_ether.h>
25 #include <linux/if_packet.h>
26 #include <sys/socket.h>
27 #include <sys/wait.h>
28 #include <linux/virtio_net.h>
29 #include <netdb.h>
30 #include <stdlib.h>
31 #include <os.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_MAX 1
38 
39 #define TOKEN_IFNAME "ifname"
40 
41 #define TRANS_RAW "raw"
42 #define TRANS_RAW_LEN strlen(TRANS_RAW)
43 
44 #define VNET_HDR_FAIL "could not enable vnet headers on fd %d"
45 #define TUN_GET_F_FAIL "tapraw: TUNGETFEATURES failed: %s"
46 #define L2TPV3_BIND_FAIL "l2tpv3_open : could not bind socket err=%i"
47 #define BPF_ATTACH_FAIL "Failed to attach filter size %d to %d, err %d\n"
48 
49 /* This is very ugly and brute force lookup, but it is done
50  * only once at initialization so not worth doing hashes or
51  * anything more intelligent
52  */
53 
54 char *uml_vector_fetch_arg(struct arglist *ifspec, char *token)
55 {
56 	int i;
57 
58 	for (i = 0; i < ifspec->numargs; i++) {
59 		if (strcmp(ifspec->tokens[i], token) == 0)
60 			return ifspec->values[i];
61 	}
62 	return NULL;
63 
64 }
65 
66 struct arglist *uml_parse_vector_ifspec(char *arg)
67 {
68 	struct arglist *result;
69 	int pos, len;
70 	bool parsing_token = true, next_starts = true;
71 
72 	if (arg == NULL)
73 		return NULL;
74 	result = uml_kmalloc(sizeof(struct arglist), UM_GFP_KERNEL);
75 	if (result == NULL)
76 		return NULL;
77 	result->numargs = 0;
78 	len = strlen(arg);
79 	for (pos = 0; pos < len; pos++) {
80 		if (next_starts) {
81 			if (parsing_token) {
82 				result->tokens[result->numargs] = arg + pos;
83 			} else {
84 				result->values[result->numargs] = arg + pos;
85 				result->numargs++;
86 			}
87 			next_starts = false;
88 		}
89 		if (*(arg + pos) == '=') {
90 			if (parsing_token)
91 				parsing_token = false;
92 			else
93 				goto cleanup;
94 			next_starts = true;
95 			(*(arg + pos)) = '\0';
96 		}
97 		if (*(arg + pos) == ',') {
98 			parsing_token = true;
99 			next_starts = true;
100 			(*(arg + pos)) = '\0';
101 		}
102 	}
103 	return result;
104 cleanup:
105 	printk(UM_KERN_ERR "vector_setup - Couldn't parse '%s'\n", arg);
106 	kfree(result);
107 	return NULL;
108 }
109 
110 /*
111  * Socket/FD configuration functions. These return an structure
112  * of rx and tx descriptors to cover cases where these are not
113  * the same (f.e. read via raw socket and write via tap).
114  */
115 
116 #define PATH_NET_TUN "/dev/net/tun"
117 
118 static struct vector_fds *user_init_tap_fds(struct arglist *ifspec)
119 {
120 	struct ifreq ifr;
121 	int fd = -1;
122 	struct sockaddr_ll sock;
123 	int err = -ENOMEM, offload;
124 	char *iface;
125 	struct vector_fds *result = NULL;
126 
127 	iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME);
128 	if (iface == NULL) {
129 		printk(UM_KERN_ERR "uml_tap: failed to parse interface spec\n");
130 		goto tap_cleanup;
131 	}
132 
133 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
134 	if (result == NULL) {
135 		printk(UM_KERN_ERR "uml_tap: failed to allocate file descriptors\n");
136 		goto tap_cleanup;
137 	}
138 	result->rx_fd = -1;
139 	result->tx_fd = -1;
140 	result->remote_addr = NULL;
141 	result->remote_addr_size = 0;
142 
143 	/* TAP */
144 
145 	fd = open(PATH_NET_TUN, O_RDWR);
146 	if (fd < 0) {
147 		printk(UM_KERN_ERR "uml_tap: failed to open tun device\n");
148 		goto tap_cleanup;
149 	}
150 	result->tx_fd = fd;
151 	memset(&ifr, 0, sizeof(ifr));
152 	ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR;
153 	strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
154 
155 	err = ioctl(fd, TUNSETIFF, (void *) &ifr);
156 	if (err != 0) {
157 		printk(UM_KERN_ERR "uml_tap: failed to select tap interface\n");
158 		goto tap_cleanup;
159 	}
160 
161 	offload = TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6;
162 	ioctl(fd, TUNSETOFFLOAD, offload);
163 
164 	/* RAW */
165 
166 	fd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
167 	if (fd == -1) {
168 		printk(UM_KERN_ERR
169 			"uml_tap: failed to create socket: %i\n", -errno);
170 		goto tap_cleanup;
171 	}
172 	result->rx_fd = fd;
173 	memset(&ifr, 0, sizeof(ifr));
174 	strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
175 	if (ioctl(fd, SIOCGIFINDEX, (void *) &ifr) < 0) {
176 		printk(UM_KERN_ERR
177 			"uml_tap: failed to set interface: %i\n", -errno);
178 		goto tap_cleanup;
179 	}
180 
181 	sock.sll_family = AF_PACKET;
182 	sock.sll_protocol = htons(ETH_P_ALL);
183 	sock.sll_ifindex = ifr.ifr_ifindex;
184 
185 	if (bind(fd,
186 		(struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
187 		printk(UM_KERN_ERR
188 			"user_init_tap: failed to bind raw pair, err %d\n",
189 				-errno);
190 		goto tap_cleanup;
191 	}
192 	return result;
193 tap_cleanup:
194 	printk(UM_KERN_ERR "user_init_tap: init failed, error %d", err);
195 	if (result != NULL) {
196 		if (result->rx_fd >= 0)
197 			os_close_file(result->rx_fd);
198 		if (result->tx_fd >= 0)
199 			os_close_file(result->tx_fd);
200 		kfree(result);
201 	}
202 	return NULL;
203 }
204 
205 
206 static struct vector_fds *user_init_raw_fds(struct arglist *ifspec)
207 {
208 	struct ifreq ifr;
209 	int rxfd = -1, txfd = -1;
210 	struct sockaddr_ll sock;
211 	int err = -ENOMEM;
212 	char *iface;
213 	struct vector_fds *result = NULL;
214 
215 	iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME);
216 	if (iface == NULL)
217 		goto cleanup;
218 
219 	rxfd = socket(AF_PACKET, SOCK_RAW, ETH_P_ALL);
220 	if (rxfd == -1) {
221 		err = -errno;
222 		goto cleanup;
223 	}
224 	txfd = socket(AF_PACKET, SOCK_RAW, 0); /* Turn off RX on this fd */
225 	if (txfd == -1) {
226 		err = -errno;
227 		goto cleanup;
228 	}
229 	memset(&ifr, 0, sizeof(ifr));
230 	strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
231 	if (ioctl(rxfd, SIOCGIFINDEX, (void *) &ifr) < 0) {
232 		err = -errno;
233 		goto cleanup;
234 	}
235 
236 	sock.sll_family = AF_PACKET;
237 	sock.sll_protocol = htons(ETH_P_ALL);
238 	sock.sll_ifindex = ifr.ifr_ifindex;
239 
240 	if (bind(rxfd,
241 		(struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
242 		err = -errno;
243 		goto cleanup;
244 	}
245 
246 	sock.sll_family = AF_PACKET;
247 	sock.sll_protocol = htons(ETH_P_IP);
248 	sock.sll_ifindex = ifr.ifr_ifindex;
249 
250 	if (bind(txfd,
251 		(struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
252 		err = -errno;
253 		goto cleanup;
254 	}
255 
256 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
257 	if (result != NULL) {
258 		result->rx_fd = rxfd;
259 		result->tx_fd = txfd;
260 		result->remote_addr = NULL;
261 		result->remote_addr_size = 0;
262 	}
263 	return result;
264 cleanup:
265 	printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err);
266 	if (rxfd >= 0)
267 		os_close_file(rxfd);
268 	if (txfd >= 0)
269 		os_close_file(txfd);
270 	if (result != NULL)
271 		kfree(result);
272 	return NULL;
273 }
274 
275 
276 bool uml_raw_enable_qdisc_bypass(int fd)
277 {
278 	int optval = 1;
279 
280 	if (setsockopt(fd,
281 		SOL_PACKET, PACKET_QDISC_BYPASS,
282 		&optval, sizeof(optval)) != 0) {
283 		return false;
284 	}
285 	return true;
286 }
287 
288 bool uml_raw_enable_vnet_headers(int fd)
289 {
290 	int optval = 1;
291 
292 	if (setsockopt(fd,
293 		SOL_PACKET, PACKET_VNET_HDR,
294 		&optval, sizeof(optval)) != 0) {
295 		printk(UM_KERN_INFO VNET_HDR_FAIL, fd);
296 		return false;
297 	}
298 	return true;
299 }
300 bool uml_tap_enable_vnet_headers(int fd)
301 {
302 	unsigned int features;
303 	int len = sizeof(struct virtio_net_hdr);
304 
305 	if (ioctl(fd, TUNGETFEATURES, &features) == -1) {
306 		printk(UM_KERN_INFO TUN_GET_F_FAIL, strerror(errno));
307 		return false;
308 	}
309 	if ((features & IFF_VNET_HDR) == 0) {
310 		printk(UM_KERN_INFO "tapraw: No VNET HEADER support");
311 		return false;
312 	}
313 	ioctl(fd, TUNSETVNETHDRSZ, &len);
314 	return true;
315 }
316 
317 static struct vector_fds *user_init_socket_fds(struct arglist *ifspec, int id)
318 {
319 	int err = -ENOMEM;
320 	int fd = -1, gairet;
321 	struct addrinfo srchints;
322 	struct addrinfo dsthints;
323 	bool v6, udp;
324 	char *value;
325 	char *src, *dst, *srcport, *dstport;
326 	struct addrinfo *gairesult = NULL;
327 	struct vector_fds *result = NULL;
328 
329 
330 	value = uml_vector_fetch_arg(ifspec, "v6");
331 	v6 = false;
332 	udp = false;
333 	if (value != NULL) {
334 		if (strtol((const char *) value, NULL, 10) > 0)
335 			v6 = true;
336 	}
337 
338 	value = uml_vector_fetch_arg(ifspec, "udp");
339 	if (value != NULL) {
340 		if (strtol((const char *) value, NULL, 10) > 0)
341 			udp = true;
342 	}
343 	src = uml_vector_fetch_arg(ifspec, "src");
344 	dst = uml_vector_fetch_arg(ifspec, "dst");
345 	srcport = uml_vector_fetch_arg(ifspec, "srcport");
346 	dstport = uml_vector_fetch_arg(ifspec, "dstport");
347 
348 	memset(&dsthints, 0, sizeof(dsthints));
349 
350 	if (v6)
351 		dsthints.ai_family = AF_INET6;
352 	else
353 		dsthints.ai_family = AF_INET;
354 
355 	switch (id) {
356 	case ID_GRE:
357 		dsthints.ai_socktype = SOCK_RAW;
358 		dsthints.ai_protocol = IPPROTO_GRE;
359 		break;
360 	case ID_L2TPV3:
361 		if (udp) {
362 			dsthints.ai_socktype = SOCK_DGRAM;
363 			dsthints.ai_protocol = 0;
364 		} else {
365 			dsthints.ai_socktype = SOCK_RAW;
366 			dsthints.ai_protocol = IPPROTO_L2TP;
367 		}
368 		break;
369 	default:
370 		printk(KERN_ERR "Unsupported socket type\n");
371 		return NULL;
372 	}
373 	memcpy(&srchints, &dsthints, sizeof(struct addrinfo));
374 
375 	gairet = getaddrinfo(src, srcport, &dsthints, &gairesult);
376 	if ((gairet != 0) || (gairesult == NULL)) {
377 		printk(UM_KERN_ERR
378 			"socket_open : could not resolve src, error = %s",
379 			gai_strerror(gairet)
380 		);
381 		return NULL;
382 	}
383 	fd = socket(gairesult->ai_family,
384 		gairesult->ai_socktype, gairesult->ai_protocol);
385 	if (fd == -1) {
386 		printk(UM_KERN_ERR
387 			"socket_open : could not open socket, error = %d",
388 			-errno
389 		);
390 		goto cleanup;
391 	}
392 	if (bind(fd,
393 		(struct sockaddr *) gairesult->ai_addr,
394 		gairesult->ai_addrlen)) {
395 		printk(UM_KERN_ERR L2TPV3_BIND_FAIL, errno);
396 		goto cleanup;
397 	}
398 
399 	if (gairesult != NULL)
400 		freeaddrinfo(gairesult);
401 
402 	gairesult = NULL;
403 
404 	gairet = getaddrinfo(dst, dstport, &dsthints, &gairesult);
405 	if ((gairet != 0) || (gairesult == NULL)) {
406 		printk(UM_KERN_ERR
407 			"socket_open : could not resolve dst, error = %s",
408 			gai_strerror(gairet)
409 		);
410 		return NULL;
411 	}
412 
413 	result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
414 	if (result != NULL) {
415 		result->rx_fd = fd;
416 		result->tx_fd = fd;
417 		result->remote_addr = uml_kmalloc(
418 			gairesult->ai_addrlen, UM_GFP_KERNEL);
419 		if (result->remote_addr == NULL)
420 			goto cleanup;
421 		result->remote_addr_size = gairesult->ai_addrlen;
422 		memcpy(
423 			result->remote_addr,
424 			gairesult->ai_addr,
425 			gairesult->ai_addrlen
426 		);
427 	}
428 	freeaddrinfo(gairesult);
429 	return result;
430 cleanup:
431 	if (gairesult != NULL)
432 		freeaddrinfo(gairesult);
433 	printk(UM_KERN_ERR "user_init_socket: init failed, error %d", err);
434 	if (fd >= 0)
435 		os_close_file(fd);
436 	if (result != NULL) {
437 		if (result->remote_addr != NULL)
438 			kfree(result->remote_addr);
439 		kfree(result);
440 	}
441 	return NULL;
442 }
443 
444 struct vector_fds *uml_vector_user_open(
445 	int unit,
446 	struct arglist *parsed
447 )
448 {
449 	char *transport;
450 
451 	if (parsed == NULL) {
452 		printk(UM_KERN_ERR "no parsed config for unit %d\n", unit);
453 		return NULL;
454 	}
455 	transport = uml_vector_fetch_arg(parsed, "transport");
456 	if (transport == NULL) {
457 		printk(UM_KERN_ERR "missing transport for unit %d\n", unit);
458 		return NULL;
459 	}
460 	if (strncmp(transport, TRANS_RAW, TRANS_RAW_LEN) == 0)
461 		return user_init_raw_fds(parsed);
462 	if (strncmp(transport, TRANS_TAP, TRANS_TAP_LEN) == 0)
463 		return user_init_tap_fds(parsed);
464 	if (strncmp(transport, TRANS_GRE, TRANS_GRE_LEN) == 0)
465 		return user_init_socket_fds(parsed, ID_GRE);
466 	if (strncmp(transport, TRANS_L2TPV3, TRANS_L2TPV3_LEN) == 0)
467 		return user_init_socket_fds(parsed, ID_L2TPV3);
468 	return NULL;
469 }
470 
471 
472 int uml_vector_sendmsg(int fd, void *hdr, int flags)
473 {
474 	int n;
475 
476 	CATCH_EINTR(n = sendmsg(fd, (struct msghdr *) hdr,  flags));
477 	if ((n < 0) && (errno == EAGAIN))
478 		return 0;
479 	if (n >= 0)
480 		return n;
481 	else
482 		return -errno;
483 }
484 
485 int uml_vector_recvmsg(int fd, void *hdr, int flags)
486 {
487 	int n;
488 
489 	CATCH_EINTR(n = recvmsg(fd, (struct msghdr *) hdr,  flags));
490 	if ((n < 0) && (errno == EAGAIN))
491 		return 0;
492 	if (n >= 0)
493 		return n;
494 	else
495 		return -errno;
496 }
497 
498 int uml_vector_writev(int fd, void *hdr, int iovcount)
499 {
500 	int n;
501 
502 	CATCH_EINTR(n = writev(fd, (struct iovec *) hdr,  iovcount));
503 	if ((n < 0) && (errno == EAGAIN))
504 		return 0;
505 	if (n >= 0)
506 		return n;
507 	else
508 		return -errno;
509 }
510 
511 int uml_vector_sendmmsg(
512 	int fd,
513 	void *msgvec,
514 	unsigned int vlen,
515 	unsigned int flags)
516 {
517 	int n;
518 
519 	CATCH_EINTR(n = sendmmsg(fd, (struct mmsghdr *) msgvec, vlen, flags));
520 	if ((n < 0) && (errno == EAGAIN))
521 		return 0;
522 	if (n >= 0)
523 		return n;
524 	else
525 		return -errno;
526 }
527 
528 int uml_vector_recvmmsg(
529 	int fd,
530 	void *msgvec,
531 	unsigned int vlen,
532 	unsigned int flags)
533 {
534 	int n;
535 
536 	CATCH_EINTR(
537 		n = recvmmsg(fd, (struct mmsghdr *) msgvec, vlen, flags, 0));
538 	if ((n < 0) && (errno == EAGAIN))
539 		return 0;
540 	if (n >= 0)
541 		return n;
542 	else
543 		return -errno;
544 }
545 int uml_vector_attach_bpf(int fd, void *bpf, int bpf_len)
546 {
547 	int err = setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, bpf, bpf_len);
548 
549 	if (err < 0)
550 		printk(KERN_ERR BPF_ATTACH_FAIL, bpf_len, fd, -errno);
551 	return err;
552 }
553 
554 #define DEFAULT_BPF_LEN 6
555 
556 void *uml_vector_default_bpf(int fd, void *mac)
557 {
558 	struct sock_filter *bpf;
559 	uint32_t *mac1 = (uint32_t *)(mac + 2);
560 	uint16_t *mac2 = (uint16_t *) mac;
561 	struct sock_fprog bpf_prog = {
562 		.len = 6,
563 		.filter = NULL,
564 	};
565 
566 	bpf = uml_kmalloc(
567 		sizeof(struct sock_filter) * DEFAULT_BPF_LEN, UM_GFP_KERNEL);
568 	if (bpf != NULL) {
569 		bpf_prog.filter = bpf;
570 		/* ld	[8] */
571 		bpf[0] = (struct sock_filter){ 0x20, 0, 0, 0x00000008 };
572 		/* jeq	#0xMAC[2-6] jt 2 jf 5*/
573 		bpf[1] = (struct sock_filter){ 0x15, 0, 3, ntohl(*mac1)};
574 		/* ldh	[6] */
575 		bpf[2] = (struct sock_filter){ 0x28, 0, 0, 0x00000006 };
576 		/* jeq	#0xMAC[0-1] jt 4 jf 5 */
577 		bpf[3] = (struct sock_filter){ 0x15, 0, 1, ntohs(*mac2)};
578 		/* ret	#0 */
579 		bpf[4] = (struct sock_filter){ 0x6, 0, 0, 0x00000000 };
580 		/* ret	#0x40000 */
581 		bpf[5] = (struct sock_filter){ 0x6, 0, 0, 0x00040000 };
582 		if (uml_vector_attach_bpf(
583 			fd, &bpf_prog, sizeof(struct sock_fprog)) < 0) {
584 			kfree(bpf);
585 			bpf = NULL;
586 		}
587 	}
588 	return bpf;
589 }
590 
591