tools/bpf/bpftool/common.c

   1 /*
   2  * Copyright (C) 2017-2018 Netronome Systems, Inc.
   3  *
   4  * This software is dual licensed under the GNU General License Version 2,
   5  * June 1991 as shown in the file COPYING in the top-level directory of this
   6  * source tree or the BSD 2-Clause License provided below.  You have the
   7  * option to license this software under the complete terms of either license.
   8  *
   9  * The BSD 2-Clause License:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      1. Redistributions of source code must retain the above
  16  *         copyright notice, this list of conditions and the following
  17  *         disclaimer.
  18  *
  19  *      2. Redistributions in binary form must reproduce the above
  20  *         copyright notice, this list of conditions and the following
  21  *         disclaimer in the documentation and/or other materials
  22  *         provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <ctype.h>
  35 #include <errno.h>
  36 #include <fcntl.h>
  37 #include <fts.h>
  38 #include <libgen.h>
  39 #include <mntent.h>
  40 #include <stdbool.h>
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44 #include <unistd.h>
  45 #include <linux/limits.h>
  46 #include <linux/magic.h>
  47 #include <net/if.h>
  48 #include <sys/mount.h>
  49 #include <sys/stat.h>
  50 #include <sys/types.h>
  51 #include <sys/vfs.h>
  52
  53 #include <bpf.h>
  54
  55 #include "main.h"
  56
  57 #ifndef BPF_FS_MAGIC
  58 #define BPF_FS_MAGIC            0xcafe4a11
  59 #endif
  60
  61 void p_err(const char *fmt, ...)
  62 {
  63         va_list ap;
  64
  65         va_start(ap, fmt);
  66         if (json_output) {
  67                 jsonw_start_object(json_wtr);
  68                 jsonw_name(json_wtr, "error");
  69                 jsonw_vprintf_enquote(json_wtr, fmt, ap);
  70                 jsonw_end_object(json_wtr);
  71         } else {
  72                 fprintf(stderr, "Error: ");
  73                 vfprintf(stderr, fmt, ap);
  74                 fprintf(stderr, "\n");
  75         }
  76         va_end(ap);
  77 }
  78
  79 void p_info(const char *fmt, ...)
  80 {
  81         va_list ap;
  82
  83         if (json_output)
  84                 return;
  85
  86         va_start(ap, fmt);
  87         vfprintf(stderr, fmt, ap);
  88         fprintf(stderr, "\n");
  89         va_end(ap);
  90 }
  91
  92 static bool is_bpffs(char *path)
  93 {
  94         struct statfs st_fs;
  95
  96         if (statfs(path, &st_fs) < 0)
  97                 return false;
  98
  99         return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
 100 }
 101
 102 static int mnt_bpffs(const char *target, char *buff, size_t bufflen)
 103 {
 104         bool bind_done = false;
 105
 106         while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
 107                 if (errno != EINVAL || bind_done) {
 108                         snprintf(buff, bufflen,
 109                                  "mount --make-private %s failed: %s",
 110                                  target, strerror(errno));
 111                         return -1;
 112                 }
 113
 114                 if (mount(target, target, "none", MS_BIND, NULL)) {
 115                         snprintf(buff, bufflen,
 116                                  "mount --bind %s %s failed: %s",
 117                                  target, target, strerror(errno));
 118                         return -1;
 119                 }
 120
 121                 bind_done = true;
 122         }
 123
 124         if (mount("bpf", target, "bpf", 0, "mode=0700")) {
 125                 snprintf(buff, bufflen, "mount -t bpf bpf %s failed: %s",
 126                          target, strerror(errno));
 127                 return -1;
 128         }
 129
 130         return 0;
 131 }
 132
 133 int open_obj_pinned(char *path, bool quiet)
 134 {
 135         int fd;
 136
 137         fd = bpf_obj_get(path);
 138         if (fd < 0) {
 139                 if (!quiet)
 140                         p_err("bpf obj get (%s): %s", path,
 141                               errno == EACCES && !is_bpffs(dirname(path)) ?
 142                             "directory not in bpf file system (bpffs)" :
 143                             strerror(errno));
 144                 return -1;
 145         }
 146
 147         return fd;
 148 }
 149
 150 int open_obj_pinned_any(char *path, enum bpf_obj_type exp_type)
 151 {
 152         enum bpf_obj_type type;
 153         int fd;
 154
 155         fd = open_obj_pinned(path, false);
 156         if (fd < 0)
 157                 return -1;
 158
 159         type = get_fd_type(fd);
 160         if (type < 0) {
 161                 close(fd);
 162                 return type;
 163         }
 164         if (type != exp_type) {
 165                 p_err("incorrect object type: %s", get_fd_type_name(type));
 166                 close(fd);
 167                 return -1;
 168         }
 169
 170         return fd;
 171 }
 172
 173 int do_pin_fd(int fd, const char *name)
 174 {
 175         char err_str[ERR_MAX_LEN];
 176         char *file;
 177         char *dir;
 178         int err = 0;
 179
 180         err = bpf_obj_pin(fd, name);
 181         if (!err)
 182                 goto out;
 183
 184         file = malloc(strlen(name) + 1);
 185         strcpy(file, name);
 186         dir = dirname(file);
 187
 188         if (errno != EPERM || is_bpffs(dir)) {
 189                 p_err("can't pin the object (%s): %s", name, strerror(errno));
 190                 goto out_free;
 191         }
 192
 193         /* Attempt to mount bpffs, then retry pinning. */
 194         err = mnt_bpffs(dir, err_str, ERR_MAX_LEN);
 195         if (!err) {
 196                 err = bpf_obj_pin(fd, name);
 197                 if (err)
 198                         p_err("can't pin the object (%s): %s", name,
 199                               strerror(errno));
 200         } else {
 201                 err_str[ERR_MAX_LEN - 1] = '\0';
 202                 p_err("can't mount BPF file system to pin the object (%s): %s",
 203                       name, err_str);
 204         }
 205
 206 out_free:
 207         free(file);
 208 out:
 209         return err;
 210 }
 211
 212 int do_pin_any(int argc, char **argv, int (*get_fd_by_id)(__u32))
 213 {
 214         unsigned int id;
 215         char *endptr;
 216         int err;
 217         int fd;
 218
 219         if (argc < 3) {
 220                 p_err("too few arguments, id ID and FILE path is required");
 221                 return -1;
 222         } else if (argc > 3) {
 223                 p_err("too many arguments");
 224                 return -1;
 225         }
 226
 227         if (!is_prefix(*argv, "id")) {
 228                 p_err("expected 'id' got %s", *argv);
 229                 return -1;
 230         }
 231         NEXT_ARG();
 232
 233         id = strtoul(*argv, &endptr, 0);
 234         if (*endptr) {
 235                 p_err("can't parse %s as ID", *argv);
 236                 return -1;
 237         }
 238         NEXT_ARG();
 239
 240         fd = get_fd_by_id(id);
 241         if (fd < 0) {
 242                 p_err("can't get prog by id (%u): %s", id, strerror(errno));
 243                 return -1;
 244         }
 245
 246         err = do_pin_fd(fd, *argv);
 247
 248         close(fd);
 249         return err;
 250 }
 251
 252 const char *get_fd_type_name(enum bpf_obj_type type)
 253 {
 254         static const char * const names[] = {
 255                 [BPF_OBJ_UNKNOWN]       = "unknown",
 256                 [BPF_OBJ_PROG]          = "prog",
 257                 [BPF_OBJ_MAP]           = "map",
 258         };
 259
 260         if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
 261                 return names[BPF_OBJ_UNKNOWN];
 262
 263         return names[type];
 264 }
 265
 266 int get_fd_type(int fd)
 267 {
 268         char path[PATH_MAX];
 269         char buf[512];
 270         ssize_t n;
 271
 272         snprintf(path, sizeof(path), "/proc/%d/fd/%d", getpid(), fd);
 273
 274         n = readlink(path, buf, sizeof(buf));
 275         if (n < 0) {
 276                 p_err("can't read link type: %s", strerror(errno));
 277                 return -1;
 278         }
 279         if (n == sizeof(path)) {
 280                 p_err("can't read link type: path too long!");
 281                 return -1;
 282         }
 283
 284         if (strstr(buf, "bpf-map"))
 285                 return BPF_OBJ_MAP;
 286         else if (strstr(buf, "bpf-prog"))
 287                 return BPF_OBJ_PROG;
 288
 289         return BPF_OBJ_UNKNOWN;
 290 }
 291
 292 char *get_fdinfo(int fd, const char *key)
 293 {
 294         char path[PATH_MAX];
 295         char *line = NULL;
 296         size_t line_n = 0;
 297         ssize_t n;
 298         FILE *fdi;
 299
 300         snprintf(path, sizeof(path), "/proc/%d/fdinfo/%d", getpid(), fd);
 301
 302         fdi = fopen(path, "r");
 303         if (!fdi) {
 304                 p_err("can't open fdinfo: %s", strerror(errno));
 305                 return NULL;
 306         }
 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                         p_err("malformed fdinfo!?");
 320                         free(line);
 321                         return NULL;
 322                 }
 323                 value++;
 324
 325                 len = strlen(value);
 326                 memmove(line, value, len);
 327                 line[len - 1] = '\0';
 328
 329                 return line;
 330         }
 331
 332         p_err("key '%s' not found in fdinfo", key);
 333         free(line);
 334         fclose(fdi);
 335         return NULL;
 336 }
 337
 338 void print_data_json(uint8_t *data, size_t len)
 339 {
 340         unsigned int i;
 341
 342         jsonw_start_array(json_wtr);
 343         for (i = 0; i < len; i++)
 344                 jsonw_printf(json_wtr, "%d", data[i]);
 345         jsonw_end_array(json_wtr);
 346 }
 347
 348 void print_hex_data_json(uint8_t *data, size_t len)
 349 {
 350         unsigned int i;
 351
 352         jsonw_start_array(json_wtr);
 353         for (i = 0; i < len; i++)
 354                 jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
 355         jsonw_end_array(json_wtr);
 356 }
 357
 358 int build_pinned_obj_table(struct pinned_obj_table *tab,
 359                            enum bpf_obj_type type)
 360 {
 361         struct bpf_prog_info pinned_info = {};
 362         struct pinned_obj *obj_node = NULL;
 363         __u32 len = sizeof(pinned_info);
 364         struct mntent *mntent = NULL;
 365         enum bpf_obj_type objtype;
 366         FILE *mntfile = NULL;
 367         FTSENT *ftse = NULL;
 368         FTS *fts = NULL;
 369         int fd, err;
 370
 371         mntfile = setmntent("/proc/mounts", "r");
 372         if (!mntfile)
 373                 return -1;
 374
 375         while ((mntent = getmntent(mntfile))) {
 376                 char *path[] = { mntent->mnt_dir, NULL };
 377
 378                 if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
 379                         continue;
 380
 381                 fts = fts_open(path, 0, NULL);
 382                 if (!fts)
 383                         continue;
 384
 385                 while ((ftse = fts_read(fts))) {
 386                         if (!(ftse->fts_info & FTS_F))
 387                                 continue;
 388                         fd = open_obj_pinned(ftse->fts_path, true);
 389                         if (fd < 0)
 390                                 continue;
 391
 392                         objtype = get_fd_type(fd);
 393                         if (objtype != type) {
 394                                 close(fd);
 395                                 continue;
 396                         }
 397                         memset(&pinned_info, 0, sizeof(pinned_info));
 398                         err = bpf_obj_get_info_by_fd(fd, &pinned_info, &len);
 399                         if (err) {
 400                                 close(fd);
 401                                 continue;
 402                         }
 403
 404                         obj_node = malloc(sizeof(*obj_node));
 405                         if (!obj_node) {
 406                                 close(fd);
 407                                 fts_close(fts);
 408                                 fclose(mntfile);
 409                                 return -1;
 410                         }
 411
 412                         memset(obj_node, 0, sizeof(*obj_node));
 413                         obj_node->id = pinned_info.id;
 414                         obj_node->path = strdup(ftse->fts_path);
 415                         hash_add(tab->table, &obj_node->hash, obj_node->id);
 416
 417                         close(fd);
 418                 }
 419                 fts_close(fts);
 420         }
 421         fclose(mntfile);
 422         return 0;
 423 }
 424
 425 void delete_pinned_obj_table(struct pinned_obj_table *tab)
 426 {
 427         struct pinned_obj *obj;
 428         struct hlist_node *tmp;
 429         unsigned int bkt;
 430
 431         hash_for_each_safe(tab->table, bkt, tmp, obj, hash) {
 432                 hash_del(&obj->hash);
 433                 free(obj->path);
 434                 free(obj);
 435         }
 436 }
 437
 438 unsigned int get_page_size(void)
 439 {
 440         static int result;
 441
 442         if (!result)
 443                 result = getpagesize();
 444         return result;
 445 }
 446
 447 unsigned int get_possible_cpus(void)
 448 {
 449         static unsigned int result;
 450         char buf[128];
 451         long int n;
 452         char *ptr;
 453         int fd;
 454
 455         if (result)
 456                 return result;
 457
 458         fd = open("/sys/devices/system/cpu/possible", O_RDONLY);
 459         if (fd < 0) {
 460                 p_err("can't open sysfs possible cpus");
 461                 exit(-1);
 462         }
 463
 464         n = read(fd, buf, sizeof(buf));
 465         if (n < 2) {
 466                 p_err("can't read sysfs possible cpus");
 467                 exit(-1);
 468         }
 469         close(fd);
 470
 471         if (n == sizeof(buf)) {
 472                 p_err("read sysfs possible cpus overflow");
 473                 exit(-1);
 474         }
 475
 476         ptr = buf;
 477         n = 0;
 478         while (*ptr && *ptr != '\n') {
 479                 unsigned int a, b;
 480
 481                 if (sscanf(ptr, "%u-%u", &a, &b) == 2) {
 482                         n += b - a + 1;
 483
 484                         ptr = strchr(ptr, '-') + 1;
 485                 } else if (sscanf(ptr, "%u", &a) == 1) {
 486                         n++;
 487                 } else {
 488                         assert(0);
 489                 }
 490
 491                 while (isdigit(*ptr))
 492                         ptr++;
 493                 if (*ptr == ',')
 494                         ptr++;
 495         }
 496
 497         result = n;
 498
 499         return result;
 500 }
 501
 502 static char *
 503 ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
 504 {
 505         struct stat st;
 506         int err;
 507
 508         err = stat("/proc/self/ns/net", &st);
 509         if (err) {
 510                 p_err("Can't stat /proc/self: %s", strerror(errno));
 511                 return NULL;
 512         }
 513
 514         if (st.st_dev != ns_dev || st.st_ino != ns_ino)
 515                 return NULL;
 516
 517         return if_indextoname(ifindex, buf);
 518 }
 519
 520 static int read_sysfs_hex_int(char *path)
 521 {
 522         char vendor_id_buf[8];
 523         int len;
 524         int fd;
 525
 526         fd = open(path, O_RDONLY);
 527         if (fd < 0) {
 528                 p_err("Can't open %s: %s", path, strerror(errno));
 529                 return -1;
 530         }
 531
 532         len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
 533         close(fd);
 534         if (len < 0) {
 535                 p_err("Can't read %s: %s", path, strerror(errno));
 536                 return -1;
 537         }
 538         if (len >= (int)sizeof(vendor_id_buf)) {
 539                 p_err("Value in %s too long", path);
 540                 return -1;
 541         }
 542
 543         vendor_id_buf[len] = 0;
 544
 545         return strtol(vendor_id_buf, NULL, 0);
 546 }
 547
 548 static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
 549 {
 550         char full_path[64];
 551
 552         snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
 553                  devname, entry_name);
 554
 555         return read_sysfs_hex_int(full_path);
 556 }
 557
 558 const char *
 559 ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
 560                       const char **opt)
 561 {
 562         char devname[IF_NAMESIZE];
 563         int vendor_id;
 564         int device_id;
 565
 566         if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
 567                 p_err("Can't get net device name for ifindex %d: %s", ifindex,
 568                       strerror(errno));
 569                 return NULL;
 570         }
 571
 572         vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
 573         if (vendor_id < 0) {
 574                 p_err("Can't get device vendor id for %s", devname);
 575                 return NULL;
 576         }
 577
 578         switch (vendor_id) {
 579         case 0x19ee:
 580                 device_id = read_sysfs_netdev_hex_int(devname, "device");
 581                 if (device_id != 0x4000 &&
 582                     device_id != 0x6000 &&
 583                     device_id != 0x6003)
 584                         p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
 585                 *opt = "ctx4";
 586                 return "NFP-6xxx";
 587         default:
 588                 p_err("Can't get bfd arch name for device vendor id 0x%04x",
 589                       vendor_id);
 590                 return NULL;
 591         }
 592 }
 593
 594 void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
 595 {
 596         char name[IF_NAMESIZE];
 597
 598         if (!ifindex)
 599                 return;
 600
 601         printf(" dev ");
 602         if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
 603                 printf("%s", name);
 604         else
 605                 printf("ifindex %u ns_dev %llu ns_ino %llu",
 606                        ifindex, ns_dev, ns_inode);
 607 }
 608
 609 void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
 610 {
 611         char name[IF_NAMESIZE];
 612
 613         if (!ifindex)
 614                 return;
 615
 616         jsonw_name(json_wtr, "dev");
 617         jsonw_start_object(json_wtr);
 618         jsonw_uint_field(json_wtr, "ifindex", ifindex);
 619         jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
 620         jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
 621         if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
 622                 jsonw_string_field(json_wtr, "ifname", name);
 623         jsonw_end_object(json_wtr);
 624 }
 625
 626 int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
 627 {
 628         char *endptr;
 629
 630         NEXT_ARGP();
 631
 632         if (*val) {
 633                 p_err("%s already specified", what);
 634                 return -1;
 635         }
 636
 637         *val = strtoul(**argv, &endptr, 0);
 638         if (*endptr) {
 639                 p_err("can't parse %s as %s", **argv, what);
 640                 return -1;
 641         }
 642         NEXT_ARGP();
 643
 644         return 0;
 645 }