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
58static const char padchar[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
59static 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
66char *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
78struct 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;
116cleanup:
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
131static 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;
155tap_fd_cleanup:
156	if (fd >= 0)
157		os_close_file(fd);
158	return err;
159}
160
161static 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;
190raw_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
198static 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;
250tap_cleanup:
251	printk(UM_KERN_ERR "user_init_tap: init failed, error %d", fd);
252	kfree(result);
253	return NULL;
254}
255
256static 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;
301hybrid_cleanup:
302	printk(UM_KERN_ERR "user_init_hybrid: init failed");
303	kfree(result);
304	return NULL;
305}
306
307static 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;
377unix_cleanup:
378	if (fd >= 0)
379		os_close_file(fd);
380	kfree(remote_addr);
381	kfree(result);
382	return NULL;
383}
384
385static 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
405static 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
430fd_cleanup:
431	if (fd >= 0)
432		os_close_file(fd);
433	kfree(result);
434	return NULL;
435}
436
437static 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;
472raw_cleanup:
473	printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err);
474	kfree(result);
475	return NULL;
476}
477
478
479bool 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
491bool 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}
503bool 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
520static 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;
633cleanup:
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
646struct 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
680int 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
693int 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
707int 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
720int 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
737int 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}
754int 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
765int 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}
774void *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
813void *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;
853bpf_failed:
854	if (ffd > 0)
855		os_close_file(ffd);
856	kfree(bpf_prog);
857	return NULL;
858}
859