1// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
  2/* Copyright (C) 2017-2018 Netronome Systems, Inc. */
  3
  4#include <ctype.h>
  5#include <errno.h>
  6#include <fcntl.h>
  7#include <fts.h>
  8#include <libgen.h>
  9#include <mntent.h>
 10#include <stdbool.h>
 11#include <stdio.h>
 12#include <stdlib.h>
 13#include <string.h>
 14#include <unistd.h>
 15#include <linux/limits.h>
 16#include <linux/magic.h>
 17#include <net/if.h>
 18#include <sys/mount.h>
 19#include <sys/resource.h>
 20#include <sys/stat.h>
 21#include <sys/vfs.h>
 22
 23#include <bpf.h>
 24#include <libbpf.h> /* libbpf_num_possible_cpus */
 25
 26#include "main.h"
 27
 28#ifndef BPF_FS_MAGIC
 29#define BPF_FS_MAGIC		0xcafe4a11
 30#endif
 31
 32void p_err(const char *fmt, ...)
 33{
 34	va_list ap;
 35
 36	va_start(ap, fmt);
 37	if (json_output) {
 38		jsonw_start_object(json_wtr);
 39		jsonw_name(json_wtr, "error");
 40		jsonw_vprintf_enquote(json_wtr, fmt, ap);
 41		jsonw_end_object(json_wtr);
 42	} else {
 43		fprintf(stderr, "Error: ");
 44		vfprintf(stderr, fmt, ap);
 45		fprintf(stderr, "\n");
 46	}
 47	va_end(ap);
 48}
 49
 50void p_info(const char *fmt, ...)
 51{
 52	va_list ap;
 53
 54	if (json_output)
 55		return;
 56
 57	va_start(ap, fmt);
 58	vfprintf(stderr, fmt, ap);
 59	fprintf(stderr, "\n");
 60	va_end(ap);
 61}
 62
 63static bool is_bpffs(char *path)
 64{
 65	struct statfs st_fs;
 66
 67	if (statfs(path, &st_fs) < 0)
 68		return false;
 69
 70	return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
 71}
 72
 73void set_max_rlimit(void)
 74{
 75	struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
 76
 77	setrlimit(RLIMIT_MEMLOCK, &rinf);
 78}
 79
 80static int
 81mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
 82{
 83	bool bind_done = false;
 84
 85	while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
 86		if (errno != EINVAL || bind_done) {
 87			snprintf(buff, bufflen,
 88				 "mount --make-private %s failed: %s",
 89				 target, strerror(errno));
 90			return -1;
 91		}
 92
 93		if (mount(target, target, "none", MS_BIND, NULL)) {
 94			snprintf(buff, bufflen,
 95				 "mount --bind %s %s failed: %s",
 96				 target, target, strerror(errno));
 97			return -1;
 98		}
 99
100		bind_done = true;
101	}
102
103	if (mount(type, target, type, 0, "mode=0700")) {
104		snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
105			 type, type, target, strerror(errno));
106		return -1;
107	}
108
109	return 0;
110}
111
112int mount_tracefs(const char *target)
113{
114	char err_str[ERR_MAX_LEN];
115	int err;
116
117	err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
118	if (err) {
119		err_str[ERR_MAX_LEN - 1] = '\0';
120		p_err("can't mount tracefs: %s", err_str);
121	}
122
123	return err;
124}
125
126int open_obj_pinned(char *path, bool quiet)
127{
128	int fd;
129
130	fd = bpf_obj_get(path);
131	if (fd < 0) {
132		if (!quiet)
133			p_err("bpf obj get (%s): %s", path,
134			      errno == EACCES && !is_bpffs(dirname(path)) ?
135			    "directory not in bpf file system (bpffs)" :
136			    strerror(errno));
137		return -1;
138	}
139
140	return fd;
141}
142
143int open_obj_pinned_any(char *path, enum bpf_obj_type exp_type)
144{
145	enum bpf_obj_type type;
146	int fd;
147
148	fd = open_obj_pinned(path, false);
149	if (fd < 0)
150		return -1;
151
152	type = get_fd_type(fd);
153	if (type < 0) {
154		close(fd);
155		return type;
156	}
157	if (type != exp_type) {
158		p_err("incorrect object type: %s", get_fd_type_name(type));
159		close(fd);
160		return -1;
161	}
162
163	return fd;
164}
165
166int mount_bpffs_for_pin(const char *name)
167{
168	char err_str[ERR_MAX_LEN];
169	char *file;
170	char *dir;
171	int err = 0;
172
173	file = malloc(strlen(name) + 1);
174	strcpy(file, name);
175	dir = dirname(file);
176
177	if (is_bpffs(dir))
178		/* nothing to do if already mounted */
179		goto out_free;
180
181	if (block_mount) {
182		p_err("no BPF file system found, not mounting it due to --nomount option");
183		err = -1;
184		goto out_free;
185	}
186
187	err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
188	if (err) {
189		err_str[ERR_MAX_LEN - 1] = '\0';
190		p_err("can't mount BPF file system to pin the object (%s): %s",
191		      name, err_str);
192	}
193
194out_free:
195	free(file);
196	return err;
197}
198
199int do_pin_fd(int fd, const char *name)
200{
201	int err;
202
203	err = mount_bpffs_for_pin(name);
204	if (err)
205		return err;
206
207	err = bpf_obj_pin(fd, name);
208	if (err)
209		p_err("can't pin the object (%s): %s", name, strerror(errno));
210
211	return err;
212}
213
214int do_pin_any(int argc, char **argv, int (*get_fd_by_id)(__u32))
215{
216	unsigned int id;
217	char *endptr;
218	int err;
219	int fd;
220
221	if (argc < 3) {
222		p_err("too few arguments, id ID and FILE path is required");
223		return -1;
224	} else if (argc > 3) {
225		p_err("too many arguments");
226		return -1;
227	}
228
229	if (!is_prefix(*argv, "id")) {
230		p_err("expected 'id' got %s", *argv);
231		return -1;
232	}
233	NEXT_ARG();
234
235	id = strtoul(*argv, &endptr, 0);
236	if (*endptr) {
237		p_err("can't parse %s as ID", *argv);
238		return -1;
239	}
240	NEXT_ARG();
241
242	fd = get_fd_by_id(id);
243	if (fd < 0) {
244		p_err("can't open object by id (%u): %s", id, strerror(errno));
245		return -1;
246	}
247
248	err = do_pin_fd(fd, *argv);
249
250	close(fd);
251	return err;
252}
253
254const char *get_fd_type_name(enum bpf_obj_type type)
255{
256	static const char * const names[] = {
257		[BPF_OBJ_UNKNOWN]	= "unknown",
258		[BPF_OBJ_PROG]		= "prog",
259		[BPF_OBJ_MAP]		= "map",
260	};
261
262	if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
263		return names[BPF_OBJ_UNKNOWN];
264
265	return names[type];
266}
267
268int get_fd_type(int fd)
269{
270	char path[PATH_MAX];
271	char buf[512];
272	ssize_t n;
273
274	snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
275
276	n = readlink(path, buf, sizeof(buf));
277	if (n < 0) {
278		p_err("can't read link type: %s", strerror(errno));
279		return -1;
280	}
281	if (n == sizeof(path)) {
282		p_err("can't read link type: path too long!");
283		return -1;
284	}
285
286	if (strstr(buf, "bpf-map"))
287		return BPF_OBJ_MAP;
288	else if (strstr(buf, "bpf-prog"))
289		return BPF_OBJ_PROG;
290
291	return BPF_OBJ_UNKNOWN;
292}
293
294char *get_fdinfo(int fd, const char *key)
295{
296	char path[PATH_MAX];
297	char *line = NULL;
298	size_t line_n = 0;
299	ssize_t n;
300	FILE *fdi;
301
302	snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
303
304	fdi = fopen(path, "r");
305	if (!fdi)
306		return NULL;
307
308	while ((n = getline(&line, &line_n, fdi)) > 0) {
309		char *value;
310		int len;
311
312		if (!strstr(line, key))
313			continue;
314
315		fclose(fdi);
316
317		value = strchr(line, '\t');
318		if (!value || !value[1]) {
319			free(line);
320			return NULL;
321		}
322		value++;
323
324		len = strlen(value);
325		memmove(line, value, len);
326		line[len - 1] = '\0';
327
328		return line;
329	}
330
331	free(line);
332	fclose(fdi);
333	return NULL;
334}
335
336void print_data_json(uint8_t *data, size_t len)
337{
338	unsigned int i;
339
340	jsonw_start_array(json_wtr);
341	for (i = 0; i < len; i++)
342		jsonw_printf(json_wtr, "%d", data[i]);
343	jsonw_end_array(json_wtr);
344}
345
346void print_hex_data_json(uint8_t *data, size_t len)
347{
348	unsigned int i;
349
350	jsonw_start_array(json_wtr);
351	for (i = 0; i < len; i++)
352		jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
353	jsonw_end_array(json_wtr);
354}
355
356int build_pinned_obj_table(struct pinned_obj_table *tab,
357			   enum bpf_obj_type type)
358{
359	struct bpf_prog_info pinned_info = {};
360	struct pinned_obj *obj_node = NULL;
361	__u32 len = sizeof(pinned_info);
362	struct mntent *mntent = NULL;
363	enum bpf_obj_type objtype;
364	FILE *mntfile = NULL;
365	FTSENT *ftse = NULL;
366	FTS *fts = NULL;
367	int fd, err;
368
369	mntfile = setmntent("/proc/mounts", "r");
370	if (!mntfile)
371		return -1;
372
373	while ((mntent = getmntent(mntfile))) {
374		char *path[] = { mntent->mnt_dir, NULL };
375
376		if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
377			continue;
378
379		fts = fts_open(path, 0, NULL);
380		if (!fts)
381			continue;
382
383		while ((ftse = fts_read(fts))) {
384			if (!(ftse->fts_info & FTS_F))
385				continue;
386			fd = open_obj_pinned(ftse->fts_path, true);
387			if (fd < 0)
388				continue;
389
390			objtype = get_fd_type(fd);
391			if (objtype != type) {
392				close(fd);
393				continue;
394			}
395			memset(&pinned_info, 0, sizeof(pinned_info));
396			err = bpf_obj_get_info_by_fd(fd, &pinned_info, &len);
397			if (err) {
398				close(fd);
399				continue;
400			}
401
402			obj_node = malloc(sizeof(*obj_node));
403			if (!obj_node) {
404				close(fd);
405				fts_close(fts);
406				fclose(mntfile);
407				return -1;
408			}
409
410			memset(obj_node, 0, sizeof(*obj_node));
411			obj_node->id = pinned_info.id;
412			obj_node->path = strdup(ftse->fts_path);
413			hash_add(tab->table, &obj_node->hash, obj_node->id);
414
415			close(fd);
416		}
417		fts_close(fts);
418	}
419	fclose(mntfile);
420	return 0;
421}
422
423void delete_pinned_obj_table(struct pinned_obj_table *tab)
424{
425	struct pinned_obj *obj;
426	struct hlist_node *tmp;
427	unsigned int bkt;
428
429	hash_for_each_safe(tab->table, bkt, tmp, obj, hash) {
430		hash_del(&obj->hash);
431		free(obj->path);
432		free(obj);
433	}
434}
435
436unsigned int get_page_size(void)
437{
438	static int result;
439
440	if (!result)
441		result = getpagesize();
442	return result;
443}
444
445unsigned int get_possible_cpus(void)
446{
447	int cpus = libbpf_num_possible_cpus();
448
449	if (cpus < 0) {
450		p_err("Can't get # of possible cpus: %s", strerror(-cpus));
451		exit(-1);
452	}
453	return cpus;
454}
455
456static char *
457ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
458{
459	struct stat st;
460	int err;
461
462	err = stat("/proc/self/ns/net", &st);
463	if (err) {
464		p_err("Can't stat /proc/self: %s", strerror(errno));
465		return NULL;
466	}
467
468	if (st.st_dev != ns_dev || st.st_ino != ns_ino)
469		return NULL;
470
471	return if_indextoname(ifindex, buf);
472}
473
474static int read_sysfs_hex_int(char *path)
475{
476	char vendor_id_buf[8];
477	int len;
478	int fd;
479
480	fd = open(path, O_RDONLY);
481	if (fd < 0) {
482		p_err("Can't open %s: %s", path, strerror(errno));
483		return -1;
484	}
485
486	len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
487	close(fd);
488	if (len < 0) {
489		p_err("Can't read %s: %s", path, strerror(errno));
490		return -1;
491	}
492	if (len >= (int)sizeof(vendor_id_buf)) {
493		p_err("Value in %s too long", path);
494		return -1;
495	}
496
497	vendor_id_buf[len] = 0;
498
499	return strtol(vendor_id_buf, NULL, 0);
500}
501
502static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
503{
504	char full_path[64];
505
506	snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
507		 devname, entry_name);
508
509	return read_sysfs_hex_int(full_path);
510}
511
512const char *
513ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
514		      const char **opt)
515{
516	char devname[IF_NAMESIZE];
517	int vendor_id;
518	int device_id;
519
520	if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
521		p_err("Can't get net device name for ifindex %d: %s", ifindex,
522		      strerror(errno));
523		return NULL;
524	}
525
526	vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
527	if (vendor_id < 0) {
528		p_err("Can't get device vendor id for %s", devname);
529		return NULL;
530	}
531
532	switch (vendor_id) {
533	case 0x19ee:
534		device_id = read_sysfs_netdev_hex_int(devname, "device");
535		if (device_id != 0x4000 &&
536		    device_id != 0x6000 &&
537		    device_id != 0x6003)
538			p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
539		*opt = "ctx4";
540		return "NFP-6xxx";
541	default:
542		p_err("Can't get bfd arch name for device vendor id 0x%04x",
543		      vendor_id);
544		return NULL;
545	}
546}
547
548void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
549{
550	char name[IF_NAMESIZE];
551
552	if (!ifindex)
553		return;
554
555	printf("  offloaded_to ");
556	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
557		printf("%s", name);
558	else
559		printf("ifindex %u ns_dev %llu ns_ino %llu",
560		       ifindex, ns_dev, ns_inode);
561}
562
563void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
564{
565	char name[IF_NAMESIZE];
566
567	if (!ifindex)
568		return;
569
570	jsonw_name(json_wtr, "dev");
571	jsonw_start_object(json_wtr);
572	jsonw_uint_field(json_wtr, "ifindex", ifindex);
573	jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
574	jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
575	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
576		jsonw_string_field(json_wtr, "ifname", name);
577	jsonw_end_object(json_wtr);
578}
579
580int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
581{
582	char *endptr;
583
584	NEXT_ARGP();
585
586	if (*val) {
587		p_err("%s already specified", what);
588		return -1;
589	}
590
591	*val = strtoul(**argv, &endptr, 0);
592	if (*endptr) {
593		p_err("can't parse %s as %s", **argv, what);
594		return -1;
595	}
596	NEXT_ARGP();
597
598	return 0;
599}