tools/bpf/bpftool/common.c

   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
  32 void __printf(1, 2) 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
  50 void __printf(1, 2) 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
  63 static 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
  73 void set_max_rlimit(void)
  74 {
  75         struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
  76
  77         setrlimit(RLIMIT_MEMLOCK, &rinf);
  78 }
  79
  80 static int
  81 mnt_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
 112 int 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
 126 int 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
 143 int 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
 166 int 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
 194 out_free:
 195         free(file);
 196         return err;
 197 }
 198
 199 int 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         return bpf_obj_pin(fd, name);
 208 }
 209
 210 int do_pin_any(int argc, char **argv, int (*get_fd_by_id)(__u32))
 211 {
 212         unsigned int id;
 213         char *endptr;
 214         int err;
 215         int fd;
 216
 217         if (argc < 3) {
 218                 p_err("too few arguments, id ID and FILE path is required");
 219                 return -1;
 220         } else if (argc > 3) {
 221                 p_err("too many arguments");
 222                 return -1;
 223         }
 224
 225         if (!is_prefix(*argv, "id")) {
 226                 p_err("expected 'id' got %s", *argv);
 227                 return -1;
 228         }
 229         NEXT_ARG();
 230
 231         id = strtoul(*argv, &endptr, 0);
 232         if (*endptr) {
 233                 p_err("can't parse %s as ID", *argv);
 234                 return -1;
 235         }
 236         NEXT_ARG();
 237
 238         fd = get_fd_by_id(id);
 239         if (fd < 0) {
 240                 p_err("can't get prog by id (%u): %s", id, strerror(errno));
 241                 return -1;
 242         }
 243
 244         err = do_pin_fd(fd, *argv);
 245
 246         close(fd);
 247         return err;
 248 }
 249
 250 const char *get_fd_type_name(enum bpf_obj_type type)
 251 {
 252         static const char * const names[] = {
 253                 [BPF_OBJ_UNKNOWN]       = "unknown",
 254                 [BPF_OBJ_PROG]          = "prog",
 255                 [BPF_OBJ_MAP]           = "map",
 256         };
 257
 258         if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
 259                 return names[BPF_OBJ_UNKNOWN];
 260
 261         return names[type];
 262 }
 263
 264 int get_fd_type(int fd)
 265 {
 266         char path[PATH_MAX];
 267         char buf[512];
 268         ssize_t n;
 269
 270         snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
 271
 272         n = readlink(path, buf, sizeof(buf));
 273         if (n < 0) {
 274                 p_err("can't read link type: %s", strerror(errno));
 275                 return -1;
 276         }
 277         if (n == sizeof(path)) {
 278                 p_err("can't read link type: path too long!");
 279                 return -1;
 280         }
 281
 282         if (strstr(buf, "bpf-map"))
 283                 return BPF_OBJ_MAP;
 284         else if (strstr(buf, "bpf-prog"))
 285                 return BPF_OBJ_PROG;
 286
 287         return BPF_OBJ_UNKNOWN;
 288 }
 289
 290 char *get_fdinfo(int fd, const char *key)
 291 {
 292         char path[PATH_MAX];
 293         char *line = NULL;
 294         size_t line_n = 0;
 295         ssize_t n;
 296         FILE *fdi;
 297
 298         snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
 299
 300         fdi = fopen(path, "r");
 301         if (!fdi)
 302                 return NULL;
 303
 304         while ((n = getline(&line, &line_n, fdi)) > 0) {
 305                 char *value;
 306                 int len;
 307
 308                 if (!strstr(line, key))
 309                         continue;
 310
 311                 fclose(fdi);
 312
 313                 value = strchr(line, '\t');
 314                 if (!value || !value[1]) {
 315                         free(line);
 316                         return NULL;
 317                 }
 318                 value++;
 319
 320                 len = strlen(value);
 321                 memmove(line, value, len);
 322                 line[len - 1] = '\0';
 323
 324                 return line;
 325         }
 326
 327         free(line);
 328         fclose(fdi);
 329         return NULL;
 330 }
 331
 332 void print_data_json(uint8_t *data, size_t len)
 333 {
 334         unsigned int i;
 335
 336         jsonw_start_array(json_wtr);
 337         for (i = 0; i < len; i++)
 338                 jsonw_printf(json_wtr, "%d", data[i]);
 339         jsonw_end_array(json_wtr);
 340 }
 341
 342 void print_hex_data_json(uint8_t *data, size_t len)
 343 {
 344         unsigned int i;
 345
 346         jsonw_start_array(json_wtr);
 347         for (i = 0; i < len; i++)
 348                 jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
 349         jsonw_end_array(json_wtr);
 350 }
 351
 352 int build_pinned_obj_table(struct pinned_obj_table *tab,
 353                            enum bpf_obj_type type)
 354 {
 355         struct bpf_prog_info pinned_info = {};
 356         struct pinned_obj *obj_node = NULL;
 357         __u32 len = sizeof(pinned_info);
 358         struct mntent *mntent = NULL;
 359         enum bpf_obj_type objtype;
 360         FILE *mntfile = NULL;
 361         FTSENT *ftse = NULL;
 362         FTS *fts = NULL;
 363         int fd, err;
 364
 365         mntfile = setmntent("/proc/mounts", "r");
 366         if (!mntfile)
 367                 return -1;
 368
 369         while ((mntent = getmntent(mntfile))) {
 370                 char *path[] = { mntent->mnt_dir, NULL };
 371
 372                 if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
 373                         continue;
 374
 375                 fts = fts_open(path, 0, NULL);
 376                 if (!fts)
 377                         continue;
 378
 379                 while ((ftse = fts_read(fts))) {
 380                         if (!(ftse->fts_info & FTS_F))
 381                                 continue;
 382                         fd = open_obj_pinned(ftse->fts_path, true);
 383                         if (fd < 0)
 384                                 continue;
 385
 386                         objtype = get_fd_type(fd);
 387                         if (objtype != type) {
 388                                 close(fd);
 389                                 continue;
 390                         }
 391                         memset(&pinned_info, 0, sizeof(pinned_info));
 392                         err = bpf_obj_get_info_by_fd(fd, &pinned_info, &len);
 393                         if (err) {
 394                                 close(fd);
 395                                 continue;
 396                         }
 397
 398                         obj_node = malloc(sizeof(*obj_node));
 399                         if (!obj_node) {
 400                                 close(fd);
 401                                 fts_close(fts);
 402                                 fclose(mntfile);
 403                                 return -1;
 404                         }
 405
 406                         memset(obj_node, 0, sizeof(*obj_node));
 407                         obj_node->id = pinned_info.id;
 408                         obj_node->path = strdup(ftse->fts_path);
 409                         hash_add(tab->table, &obj_node->hash, obj_node->id);
 410
 411                         close(fd);
 412                 }
 413                 fts_close(fts);
 414         }
 415         fclose(mntfile);
 416         return 0;
 417 }
 418
 419 void delete_pinned_obj_table(struct pinned_obj_table *tab)
 420 {
 421         struct pinned_obj *obj;
 422         struct hlist_node *tmp;
 423         unsigned int bkt;
 424
 425         hash_for_each_safe(tab->table, bkt, tmp, obj, hash) {
 426                 hash_del(&obj->hash);
 427                 free(obj->path);
 428                 free(obj);
 429         }
 430 }
 431
 432 unsigned int get_page_size(void)
 433 {
 434         static int result;
 435
 436         if (!result)
 437                 result = getpagesize();
 438         return result;
 439 }
 440
 441 unsigned int get_possible_cpus(void)
 442 {
 443         int cpus = libbpf_num_possible_cpus();
 444
 445         if (cpus < 0) {
 446                 p_err("Can't get # of possible cpus: %s", strerror(-cpus));
 447                 exit(-1);
 448         }
 449         return cpus;
 450 }
 451
 452 static char *
 453 ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
 454 {
 455         struct stat st;
 456         int err;
 457
 458         err = stat("/proc/self/ns/net", &st);
 459         if (err) {
 460                 p_err("Can't stat /proc/self: %s", strerror(errno));
 461                 return NULL;
 462         }
 463
 464         if (st.st_dev != ns_dev || st.st_ino != ns_ino)
 465                 return NULL;
 466
 467         return if_indextoname(ifindex, buf);
 468 }
 469
 470 static int read_sysfs_hex_int(char *path)
 471 {
 472         char vendor_id_buf[8];
 473         int len;
 474         int fd;
 475
 476         fd = open(path, O_RDONLY);
 477         if (fd < 0) {
 478                 p_err("Can't open %s: %s", path, strerror(errno));
 479                 return -1;
 480         }
 481
 482         len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
 483         close(fd);
 484         if (len < 0) {
 485                 p_err("Can't read %s: %s", path, strerror(errno));
 486                 return -1;
 487         }
 488         if (len >= (int)sizeof(vendor_id_buf)) {
 489                 p_err("Value in %s too long", path);
 490                 return -1;
 491         }
 492
 493         vendor_id_buf[len] = 0;
 494
 495         return strtol(vendor_id_buf, NULL, 0);
 496 }
 497
 498 static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
 499 {
 500         char full_path[64];
 501
 502         snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
 503                  devname, entry_name);
 504
 505         return read_sysfs_hex_int(full_path);
 506 }
 507
 508 const char *
 509 ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
 510                       const char **opt)
 511 {
 512         char devname[IF_NAMESIZE];
 513         int vendor_id;
 514         int device_id;
 515
 516         if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
 517                 p_err("Can't get net device name for ifindex %d: %s", ifindex,
 518                       strerror(errno));
 519                 return NULL;
 520         }
 521
 522         vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
 523         if (vendor_id < 0) {
 524                 p_err("Can't get device vendor id for %s", devname);
 525                 return NULL;
 526         }
 527
 528         switch (vendor_id) {
 529         case 0x19ee:
 530                 device_id = read_sysfs_netdev_hex_int(devname, "device");
 531                 if (device_id != 0x4000 &&
 532                     device_id != 0x6000 &&
 533                     device_id != 0x6003)
 534                         p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
 535                 *opt = "ctx4";
 536                 return "NFP-6xxx";
 537         default:
 538                 p_err("Can't get bfd arch name for device vendor id 0x%04x",
 539                       vendor_id);
 540                 return NULL;
 541         }
 542 }
 543
 544 void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
 545 {
 546         char name[IF_NAMESIZE];
 547
 548         if (!ifindex)
 549                 return;
 550
 551         printf("  offloaded_to ");
 552         if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
 553                 printf("%s", name);
 554         else
 555                 printf("ifindex %u ns_dev %llu ns_ino %llu",
 556                        ifindex, ns_dev, ns_inode);
 557 }
 558
 559 void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
 560 {
 561         char name[IF_NAMESIZE];
 562
 563         if (!ifindex)
 564                 return;
 565
 566         jsonw_name(json_wtr, "dev");
 567         jsonw_start_object(json_wtr);
 568         jsonw_uint_field(json_wtr, "ifindex", ifindex);
 569         jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
 570         jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
 571         if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
 572                 jsonw_string_field(json_wtr, "ifname", name);
 573         jsonw_end_object(json_wtr);
 574 }
 575
 576 int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
 577 {
 578         char *endptr;
 579
 580         NEXT_ARGP();
 581
 582         if (*val) {
 583                 p_err("%s already specified", what);
 584                 return -1;
 585         }
 586
 587         *val = strtoul(**argv, &endptr, 0);
 588         if (*endptr) {
 589                 p_err("can't parse %s as %s", **argv, what);
 590                 return -1;
 591         }
 592         NEXT_ARGP();
 593
 594         return 0;
 595 }