whiterose

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common.c (12051B)


      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 
     25 #include "main.h"
     26 
     27 #ifndef BPF_FS_MAGIC
     28 #define BPF_FS_MAGIC		0xcafe4a11
     29 #endif
     30 
     31 void __printf(1, 2) p_err(const char *fmt, ...)
     32 {
     33 	va_list ap;
     34 
     35 	va_start(ap, fmt);
     36 	if (json_output) {
     37 		jsonw_start_object(json_wtr);
     38 		jsonw_name(json_wtr, "error");
     39 		jsonw_vprintf_enquote(json_wtr, fmt, ap);
     40 		jsonw_end_object(json_wtr);
     41 	} else {
     42 		fprintf(stderr, "Error: ");
     43 		vfprintf(stderr, fmt, ap);
     44 		fprintf(stderr, "\n");
     45 	}
     46 	va_end(ap);
     47 }
     48 
     49 void __printf(1, 2) p_info(const char *fmt, ...)
     50 {
     51 	va_list ap;
     52 
     53 	if (json_output)
     54 		return;
     55 
     56 	va_start(ap, fmt);
     57 	vfprintf(stderr, fmt, ap);
     58 	fprintf(stderr, "\n");
     59 	va_end(ap);
     60 }
     61 
     62 static bool is_bpffs(char *path)
     63 {
     64 	struct statfs st_fs;
     65 
     66 	if (statfs(path, &st_fs) < 0)
     67 		return false;
     68 
     69 	return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
     70 }
     71 
     72 void set_max_rlimit(void)
     73 {
     74 	struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
     75 
     76 	setrlimit(RLIMIT_MEMLOCK, &rinf);
     77 }
     78 
     79 static int
     80 mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
     81 {
     82 	bool bind_done = false;
     83 
     84 	while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
     85 		if (errno != EINVAL || bind_done) {
     86 			snprintf(buff, bufflen,
     87 				 "mount --make-private %s failed: %s",
     88 				 target, strerror(errno));
     89 			return -1;
     90 		}
     91 
     92 		if (mount(target, target, "none", MS_BIND, NULL)) {
     93 			snprintf(buff, bufflen,
     94 				 "mount --bind %s %s failed: %s",
     95 				 target, target, strerror(errno));
     96 			return -1;
     97 		}
     98 
     99 		bind_done = true;
    100 	}
    101 
    102 	if (mount(type, target, type, 0, "mode=0700")) {
    103 		snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
    104 			 type, type, target, strerror(errno));
    105 		return -1;
    106 	}
    107 
    108 	return 0;
    109 }
    110 
    111 int mount_tracefs(const char *target)
    112 {
    113 	char err_str[ERR_MAX_LEN];
    114 	int err;
    115 
    116 	err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
    117 	if (err) {
    118 		err_str[ERR_MAX_LEN - 1] = '\0';
    119 		p_err("can't mount tracefs: %s", err_str);
    120 	}
    121 
    122 	return err;
    123 }
    124 
    125 int open_obj_pinned(char *path, bool quiet)
    126 {
    127 	int fd;
    128 
    129 	fd = bpf_obj_get(path);
    130 	if (fd < 0) {
    131 		if (!quiet)
    132 			p_err("bpf obj get (%s): %s", path,
    133 			      errno == EACCES && !is_bpffs(dirname(path)) ?
    134 			    "directory not in bpf file system (bpffs)" :
    135 			    strerror(errno));
    136 		return -1;
    137 	}
    138 
    139 	return fd;
    140 }
    141 
    142 int open_obj_pinned_any(char *path, enum bpf_obj_type exp_type)
    143 {
    144 	enum bpf_obj_type type;
    145 	int fd;
    146 
    147 	fd = open_obj_pinned(path, false);
    148 	if (fd < 0)
    149 		return -1;
    150 
    151 	type = get_fd_type(fd);
    152 	if (type < 0) {
    153 		close(fd);
    154 		return type;
    155 	}
    156 	if (type != exp_type) {
    157 		p_err("incorrect object type: %s", get_fd_type_name(type));
    158 		close(fd);
    159 		return -1;
    160 	}
    161 
    162 	return fd;
    163 }
    164 
    165 int mount_bpffs_for_pin(const char *name)
    166 {
    167 	char err_str[ERR_MAX_LEN];
    168 	char *file;
    169 	char *dir;
    170 	int err = 0;
    171 
    172 	file = malloc(strlen(name) + 1);
    173 	strcpy(file, name);
    174 	dir = dirname(file);
    175 
    176 	if (is_bpffs(dir))
    177 		/* nothing to do if already mounted */
    178 		goto out_free;
    179 
    180 	if (block_mount) {
    181 		p_err("no BPF file system found, not mounting it due to --nomount option");
    182 		err = -1;
    183 		goto out_free;
    184 	}
    185 
    186 	err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
    187 	if (err) {
    188 		err_str[ERR_MAX_LEN - 1] = '\0';
    189 		p_err("can't mount BPF file system to pin the object (%s): %s",
    190 		      name, err_str);
    191 	}
    192 
    193 out_free:
    194 	free(file);
    195 	return err;
    196 }
    197 
    198 int do_pin_fd(int fd, const char *name)
    199 {
    200 	int err;
    201 
    202 	err = mount_bpffs_for_pin(name);
    203 	if (err)
    204 		return err;
    205 
    206 	return bpf_obj_pin(fd, name);
    207 }
    208 
    209 int do_pin_any(int argc, char **argv, int (*get_fd_by_id)(__u32))
    210 {
    211 	unsigned int id;
    212 	char *endptr;
    213 	int err;
    214 	int fd;
    215 
    216 	if (argc < 3) {
    217 		p_err("too few arguments, id ID and FILE path is required");
    218 		return -1;
    219 	} else if (argc > 3) {
    220 		p_err("too many arguments");
    221 		return -1;
    222 	}
    223 
    224 	if (!is_prefix(*argv, "id")) {
    225 		p_err("expected 'id' got %s", *argv);
    226 		return -1;
    227 	}
    228 	NEXT_ARG();
    229 
    230 	id = strtoul(*argv, &endptr, 0);
    231 	if (*endptr) {
    232 		p_err("can't parse %s as ID", *argv);
    233 		return -1;
    234 	}
    235 	NEXT_ARG();
    236 
    237 	fd = get_fd_by_id(id);
    238 	if (fd < 0) {
    239 		p_err("can't get prog by id (%u): %s", id, strerror(errno));
    240 		return -1;
    241 	}
    242 
    243 	err = do_pin_fd(fd, *argv);
    244 
    245 	close(fd);
    246 	return err;
    247 }
    248 
    249 const char *get_fd_type_name(enum bpf_obj_type type)
    250 {
    251 	static const char * const names[] = {
    252 		[BPF_OBJ_UNKNOWN]	= "unknown",
    253 		[BPF_OBJ_PROG]		= "prog",
    254 		[BPF_OBJ_MAP]		= "map",
    255 	};
    256 
    257 	if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
    258 		return names[BPF_OBJ_UNKNOWN];
    259 
    260 	return names[type];
    261 }
    262 
    263 int get_fd_type(int fd)
    264 {
    265 	char path[PATH_MAX];
    266 	char buf[512];
    267 	ssize_t n;
    268 
    269 	snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
    270 
    271 	n = readlink(path, buf, sizeof(buf));
    272 	if (n < 0) {
    273 		p_err("can't read link type: %s", strerror(errno));
    274 		return -1;
    275 	}
    276 	if (n == sizeof(path)) {
    277 		p_err("can't read link type: path too long!");
    278 		return -1;
    279 	}
    280 
    281 	if (strstr(buf, "bpf-map"))
    282 		return BPF_OBJ_MAP;
    283 	else if (strstr(buf, "bpf-prog"))
    284 		return BPF_OBJ_PROG;
    285 
    286 	return BPF_OBJ_UNKNOWN;
    287 }
    288 
    289 char *get_fdinfo(int fd, const char *key)
    290 {
    291 	char path[PATH_MAX];
    292 	char *line = NULL;
    293 	size_t line_n = 0;
    294 	ssize_t n;
    295 	FILE *fdi;
    296 
    297 	snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
    298 
    299 	fdi = fopen(path, "r");
    300 	if (!fdi)
    301 		return NULL;
    302 
    303 	while ((n = getline(&line, &line_n, fdi)) > 0) {
    304 		char *value;
    305 		int len;
    306 
    307 		if (!strstr(line, key))
    308 			continue;
    309 
    310 		fclose(fdi);
    311 
    312 		value = strchr(line, '\t');
    313 		if (!value || !value[1]) {
    314 			free(line);
    315 			return NULL;
    316 		}
    317 		value++;
    318 
    319 		len = strlen(value);
    320 		memmove(line, value, len);
    321 		line[len - 1] = '\0';
    322 
    323 		return line;
    324 	}
    325 
    326 	free(line);
    327 	fclose(fdi);
    328 	return NULL;
    329 }
    330 
    331 void print_data_json(uint8_t *data, size_t len)
    332 {
    333 	unsigned int i;
    334 
    335 	jsonw_start_array(json_wtr);
    336 	for (i = 0; i < len; i++)
    337 		jsonw_printf(json_wtr, "%d", data[i]);
    338 	jsonw_end_array(json_wtr);
    339 }
    340 
    341 void print_hex_data_json(uint8_t *data, size_t len)
    342 {
    343 	unsigned int i;
    344 
    345 	jsonw_start_array(json_wtr);
    346 	for (i = 0; i < len; i++)
    347 		jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
    348 	jsonw_end_array(json_wtr);
    349 }
    350 
    351 int build_pinned_obj_table(struct pinned_obj_table *tab,
    352 			   enum bpf_obj_type type)
    353 {
    354 	struct bpf_prog_info pinned_info = {};
    355 	struct pinned_obj *obj_node = NULL;
    356 	__u32 len = sizeof(pinned_info);
    357 	struct mntent *mntent = NULL;
    358 	enum bpf_obj_type objtype;
    359 	FILE *mntfile = NULL;
    360 	FTSENT *ftse = NULL;
    361 	FTS *fts = NULL;
    362 	int fd, err;
    363 
    364 	mntfile = setmntent("/proc/mounts", "r");
    365 	if (!mntfile)
    366 		return -1;
    367 
    368 	while ((mntent = getmntent(mntfile))) {
    369 		char *path[] = { mntent->mnt_dir, NULL };
    370 
    371 		if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
    372 			continue;
    373 
    374 		fts = fts_open(path, 0, NULL);
    375 		if (!fts)
    376 			continue;
    377 
    378 		while ((ftse = fts_read(fts))) {
    379 			if (!(ftse->fts_info & FTS_F))
    380 				continue;
    381 			fd = open_obj_pinned(ftse->fts_path, true);
    382 			if (fd < 0)
    383 				continue;
    384 
    385 			objtype = get_fd_type(fd);
    386 			if (objtype != type) {
    387 				close(fd);
    388 				continue;
    389 			}
    390 			memset(&pinned_info, 0, sizeof(pinned_info));
    391 			err = bpf_obj_get_info_by_fd(fd, &pinned_info, &len);
    392 			if (err) {
    393 				close(fd);
    394 				continue;
    395 			}
    396 
    397 			obj_node = malloc(sizeof(*obj_node));
    398 			if (!obj_node) {
    399 				close(fd);
    400 				fts_close(fts);
    401 				fclose(mntfile);
    402 				return -1;
    403 			}
    404 
    405 			memset(obj_node, 0, sizeof(*obj_node));
    406 			obj_node->id = pinned_info.id;
    407 			obj_node->path = strdup(ftse->fts_path);
    408 			hash_add(tab->table, &obj_node->hash, obj_node->id);
    409 
    410 			close(fd);
    411 		}
    412 		fts_close(fts);
    413 	}
    414 	fclose(mntfile);
    415 	return 0;
    416 }
    417 
    418 void delete_pinned_obj_table(struct pinned_obj_table *tab)
    419 {
    420 	struct pinned_obj *obj;
    421 	struct hlist_node *tmp;
    422 	unsigned int bkt;
    423 
    424 	hash_for_each_safe(tab->table, bkt, tmp, obj, hash) {
    425 		hash_del(&obj->hash);
    426 		free(obj->path);
    427 		free(obj);
    428 	}
    429 }
    430 
    431 unsigned int get_page_size(void)
    432 {
    433 	static int result;
    434 
    435 	if (!result)
    436 		result = getpagesize();
    437 	return result;
    438 }
    439 
    440 unsigned int get_possible_cpus(void)
    441 {
    442 	static unsigned int result;
    443 	char buf[128];
    444 	long int n;
    445 	char *ptr;
    446 	int fd;
    447 
    448 	if (result)
    449 		return result;
    450 
    451 	fd = open("/sys/devices/system/cpu/possible", O_RDONLY);
    452 	if (fd < 0) {
    453 		p_err("can't open sysfs possible cpus");
    454 		exit(-1);
    455 	}
    456 
    457 	n = read(fd, buf, sizeof(buf));
    458 	if (n < 2) {
    459 		p_err("can't read sysfs possible cpus");
    460 		exit(-1);
    461 	}
    462 	close(fd);
    463 
    464 	if (n == sizeof(buf)) {
    465 		p_err("read sysfs possible cpus overflow");
    466 		exit(-1);
    467 	}
    468 
    469 	ptr = buf;
    470 	n = 0;
    471 	while (*ptr && *ptr != '\n') {
    472 		unsigned int a, b;
    473 
    474 		if (sscanf(ptr, "%u-%u", &a, &b) == 2) {
    475 			n += b - a + 1;
    476 
    477 			ptr = strchr(ptr, '-') + 1;
    478 		} else if (sscanf(ptr, "%u", &a) == 1) {
    479 			n++;
    480 		} else {
    481 			assert(0);
    482 		}
    483 
    484 		while (isdigit(*ptr))
    485 			ptr++;
    486 		if (*ptr == ',')
    487 			ptr++;
    488 	}
    489 
    490 	result = n;
    491 
    492 	return result;
    493 }
    494 
    495 static char *
    496 ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
    497 {
    498 	struct stat st;
    499 	int err;
    500 
    501 	err = stat("/proc/self/ns/net", &st);
    502 	if (err) {
    503 		p_err("Can't stat /proc/self: %s", strerror(errno));
    504 		return NULL;
    505 	}
    506 
    507 	if (st.st_dev != ns_dev || st.st_ino != ns_ino)
    508 		return NULL;
    509 
    510 	return if_indextoname(ifindex, buf);
    511 }
    512 
    513 static int read_sysfs_hex_int(char *path)
    514 {
    515 	char vendor_id_buf[8];
    516 	int len;
    517 	int fd;
    518 
    519 	fd = open(path, O_RDONLY);
    520 	if (fd < 0) {
    521 		p_err("Can't open %s: %s", path, strerror(errno));
    522 		return -1;
    523 	}
    524 
    525 	len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
    526 	close(fd);
    527 	if (len < 0) {
    528 		p_err("Can't read %s: %s", path, strerror(errno));
    529 		return -1;
    530 	}
    531 	if (len >= (int)sizeof(vendor_id_buf)) {
    532 		p_err("Value in %s too long", path);
    533 		return -1;
    534 	}
    535 
    536 	vendor_id_buf[len] = 0;
    537 
    538 	return strtol(vendor_id_buf, NULL, 0);
    539 }
    540 
    541 static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
    542 {
    543 	char full_path[64];
    544 
    545 	snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
    546 		 devname, entry_name);
    547 
    548 	return read_sysfs_hex_int(full_path);
    549 }
    550 
    551 const char *
    552 ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
    553 		      const char **opt)
    554 {
    555 	char devname[IF_NAMESIZE];
    556 	int vendor_id;
    557 	int device_id;
    558 
    559 	if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
    560 		p_err("Can't get net device name for ifindex %d: %s", ifindex,
    561 		      strerror(errno));
    562 		return NULL;
    563 	}
    564 
    565 	vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
    566 	if (vendor_id < 0) {
    567 		p_err("Can't get device vendor id for %s", devname);
    568 		return NULL;
    569 	}
    570 
    571 	switch (vendor_id) {
    572 	case 0x19ee:
    573 		device_id = read_sysfs_netdev_hex_int(devname, "device");
    574 		if (device_id != 0x4000 &&
    575 		    device_id != 0x6000 &&
    576 		    device_id != 0x6003)
    577 			p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
    578 		*opt = "ctx4";
    579 		return "NFP-6xxx";
    580 	default:
    581 		p_err("Can't get bfd arch name for device vendor id 0x%04x",
    582 		      vendor_id);
    583 		return NULL;
    584 	}
    585 }
    586 
    587 void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
    588 {
    589 	char name[IF_NAMESIZE];
    590 
    591 	if (!ifindex)
    592 		return;
    593 
    594 	printf("  offloaded_to ");
    595 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
    596 		printf("%s", name);
    597 	else
    598 		printf("ifindex %u ns_dev %llu ns_ino %llu",
    599 		       ifindex, ns_dev, ns_inode);
    600 }
    601 
    602 void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
    603 {
    604 	char name[IF_NAMESIZE];
    605 
    606 	if (!ifindex)
    607 		return;
    608 
    609 	jsonw_name(json_wtr, "dev");
    610 	jsonw_start_object(json_wtr);
    611 	jsonw_uint_field(json_wtr, "ifindex", ifindex);
    612 	jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
    613 	jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
    614 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
    615 		jsonw_string_field(json_wtr, "ifname", name);
    616 	jsonw_end_object(json_wtr);
    617 }
    618 
    619 int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
    620 {
    621 	char *endptr;
    622 
    623 	NEXT_ARGP();
    624 
    625 	if (*val) {
    626 		p_err("%s already specified", what);
    627 		return -1;
    628 	}
    629 
    630 	*val = strtoul(**argv, &endptr, 0);
    631 	if (*endptr) {
    632 		p_err("can't parse %s as %s", **argv, what);
    633 		return -1;
    634 	}
    635 	NEXT_ARGP();
    636 
    637 	return 0;
    638 }