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 #define _GNU_SOURCE
   5 #include <ctype.h>
   6 #include <errno.h>
   7 #include <fcntl.h>
   8 #include <ftw.h>
   9 #include <libgen.h>
  10 #include <mntent.h>
  11 #include <stdbool.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include <unistd.h>
  16 #include <linux/limits.h>
  17 #include <linux/magic.h>
  18 #include <net/if.h>
  19 #include <sys/mount.h>
  20 #include <sys/resource.h>
  21 #include <sys/stat.h>
  22 #include <sys/vfs.h>
  23
  24 #include <bpf/bpf.h>
  25 #include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
  26
  27 #include "main.h"
  28
  29 #ifndef BPF_FS_MAGIC
  30 #define BPF_FS_MAGIC            0xcafe4a11
  31 #endif
  32
  33 const char * const attach_type_name[__MAX_BPF_ATTACH_TYPE] = {
  34         [BPF_CGROUP_INET_INGRESS]       = "ingress",
  35         [BPF_CGROUP_INET_EGRESS]        = "egress",
  36         [BPF_CGROUP_INET_SOCK_CREATE]   = "sock_create",
  37         [BPF_CGROUP_INET_SOCK_RELEASE]  = "sock_release",
  38         [BPF_CGROUP_SOCK_OPS]           = "sock_ops",
  39         [BPF_CGROUP_DEVICE]             = "device",
  40         [BPF_CGROUP_INET4_BIND]         = "bind4",
  41         [BPF_CGROUP_INET6_BIND]         = "bind6",
  42         [BPF_CGROUP_INET4_CONNECT]      = "connect4",
  43         [BPF_CGROUP_INET6_CONNECT]      = "connect6",
  44         [BPF_CGROUP_INET4_POST_BIND]    = "post_bind4",
  45         [BPF_CGROUP_INET6_POST_BIND]    = "post_bind6",
  46         [BPF_CGROUP_INET4_GETPEERNAME]  = "getpeername4",
  47         [BPF_CGROUP_INET6_GETPEERNAME]  = "getpeername6",
  48         [BPF_CGROUP_INET4_GETSOCKNAME]  = "getsockname4",
  49         [BPF_CGROUP_INET6_GETSOCKNAME]  = "getsockname6",
  50         [BPF_CGROUP_UDP4_SENDMSG]       = "sendmsg4",
  51         [BPF_CGROUP_UDP6_SENDMSG]       = "sendmsg6",
  52         [BPF_CGROUP_SYSCTL]             = "sysctl",
  53         [BPF_CGROUP_UDP4_RECVMSG]       = "recvmsg4",
  54         [BPF_CGROUP_UDP6_RECVMSG]       = "recvmsg6",
  55         [BPF_CGROUP_GETSOCKOPT]         = "getsockopt",
  56         [BPF_CGROUP_SETSOCKOPT]         = "setsockopt",
  57
  58         [BPF_SK_SKB_STREAM_PARSER]      = "sk_skb_stream_parser",
  59         [BPF_SK_SKB_STREAM_VERDICT]     = "sk_skb_stream_verdict",
  60         [BPF_SK_SKB_VERDICT]            = "sk_skb_verdict",
  61         [BPF_SK_MSG_VERDICT]            = "sk_msg_verdict",
  62         [BPF_LIRC_MODE2]                = "lirc_mode2",
  63         [BPF_FLOW_DISSECTOR]            = "flow_dissector",
  64         [BPF_TRACE_RAW_TP]              = "raw_tp",
  65         [BPF_TRACE_FENTRY]              = "fentry",
  66         [BPF_TRACE_FEXIT]               = "fexit",
  67         [BPF_MODIFY_RETURN]             = "mod_ret",
  68         [BPF_LSM_MAC]                   = "lsm_mac",
  69         [BPF_SK_LOOKUP]                 = "sk_lookup",
  70         [BPF_TRACE_ITER]                = "trace_iter",
  71         [BPF_XDP_DEVMAP]                = "xdp_devmap",
  72         [BPF_XDP_CPUMAP]                = "xdp_cpumap",
  73         [BPF_XDP]                       = "xdp",
  74         [BPF_SK_REUSEPORT_SELECT]       = "sk_skb_reuseport_select",
  75         [BPF_SK_REUSEPORT_SELECT_OR_MIGRATE]    = "sk_skb_reuseport_select_or_migrate",
  76 };
  77
  78 void p_err(const char *fmt, ...)
  79 {
  80         va_list ap;
  81
  82         va_start(ap, fmt);
  83         if (json_output) {
  84                 jsonw_start_object(json_wtr);
  85                 jsonw_name(json_wtr, "error");
  86                 jsonw_vprintf_enquote(json_wtr, fmt, ap);
  87                 jsonw_end_object(json_wtr);
  88         } else {
  89                 fprintf(stderr, "Error: ");
  90                 vfprintf(stderr, fmt, ap);
  91                 fprintf(stderr, "\n");
  92         }
  93         va_end(ap);
  94 }
  95
  96 void p_info(const char *fmt, ...)
  97 {
  98         va_list ap;
  99
 100         if (json_output)
 101                 return;
 102
 103         va_start(ap, fmt);
 104         vfprintf(stderr, fmt, ap);
 105         fprintf(stderr, "\n");
 106         va_end(ap);
 107 }
 108
 109 static bool is_bpffs(char *path)
 110 {
 111         struct statfs st_fs;
 112
 113         if (statfs(path, &st_fs) < 0)
 114                 return false;
 115
 116         return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
 117 }
 118
 119 void set_max_rlimit(void)
 120 {
 121         struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
 122
 123         setrlimit(RLIMIT_MEMLOCK, &rinf);
 124 }
 125
 126 static int
 127 mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
 128 {
 129         bool bind_done = false;
 130
 131         while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
 132                 if (errno != EINVAL || bind_done) {
 133                         snprintf(buff, bufflen,
 134                                  "mount --make-private %s failed: %s",
 135                                  target, strerror(errno));
 136                         return -1;
 137                 }
 138
 139                 if (mount(target, target, "none", MS_BIND, NULL)) {
 140                         snprintf(buff, bufflen,
 141                                  "mount --bind %s %s failed: %s",
 142                                  target, target, strerror(errno));
 143                         return -1;
 144                 }
 145
 146                 bind_done = true;
 147         }
 148
 149         if (mount(type, target, type, 0, "mode=0700")) {
 150                 snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
 151                          type, type, target, strerror(errno));
 152                 return -1;
 153         }
 154
 155         return 0;
 156 }
 157
 158 int mount_tracefs(const char *target)
 159 {
 160         char err_str[ERR_MAX_LEN];
 161         int err;
 162
 163         err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
 164         if (err) {
 165                 err_str[ERR_MAX_LEN - 1] = '\0';
 166                 p_err("can't mount tracefs: %s", err_str);
 167         }
 168
 169         return err;
 170 }
 171
 172 int open_obj_pinned(const char *path, bool quiet)
 173 {
 174         char *pname;
 175         int fd = -1;
 176
 177         pname = strdup(path);
 178         if (!pname) {
 179                 if (!quiet)
 180                         p_err("mem alloc failed");
 181                 goto out_ret;
 182         }
 183
 184         fd = bpf_obj_get(pname);
 185         if (fd < 0) {
 186                 if (!quiet)
 187                         p_err("bpf obj get (%s): %s", pname,
 188                               errno == EACCES && !is_bpffs(dirname(pname)) ?
 189                             "directory not in bpf file system (bpffs)" :
 190                             strerror(errno));
 191                 goto out_free;
 192         }
 193
 194 out_free:
 195         free(pname);
 196 out_ret:
 197         return fd;
 198 }
 199
 200 int open_obj_pinned_any(const char *path, enum bpf_obj_type exp_type)
 201 {
 202         enum bpf_obj_type type;
 203         int fd;
 204
 205         fd = open_obj_pinned(path, false);
 206         if (fd < 0)
 207                 return -1;
 208
 209         type = get_fd_type(fd);
 210         if (type < 0) {
 211                 close(fd);
 212                 return type;
 213         }
 214         if (type != exp_type) {
 215                 p_err("incorrect object type: %s", get_fd_type_name(type));
 216                 close(fd);
 217                 return -1;
 218         }
 219
 220         return fd;
 221 }
 222
 223 int mount_bpffs_for_pin(const char *name)
 224 {
 225         char err_str[ERR_MAX_LEN];
 226         char *file;
 227         char *dir;
 228         int err = 0;
 229
 230         file = malloc(strlen(name) + 1);
 231         strcpy(file, name);
 232         dir = dirname(file);
 233
 234         if (is_bpffs(dir))
 235                 /* nothing to do if already mounted */
 236                 goto out_free;
 237
 238         if (block_mount) {
 239                 p_err("no BPF file system found, not mounting it due to --nomount option");
 240                 err = -1;
 241                 goto out_free;
 242         }
 243
 244         err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
 245         if (err) {
 246                 err_str[ERR_MAX_LEN - 1] = '\0';
 247                 p_err("can't mount BPF file system to pin the object (%s): %s",
 248                       name, err_str);
 249         }
 250
 251 out_free:
 252         free(file);
 253         return err;
 254 }
 255
 256 int do_pin_fd(int fd, const char *name)
 257 {
 258         int err;
 259
 260         err = mount_bpffs_for_pin(name);
 261         if (err)
 262                 return err;
 263
 264         err = bpf_obj_pin(fd, name);
 265         if (err)
 266                 p_err("can't pin the object (%s): %s", name, strerror(errno));
 267
 268         return err;
 269 }
 270
 271 int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
 272 {
 273         int err;
 274         int fd;
 275
 276         fd = get_fd(&argc, &argv);
 277         if (fd < 0)
 278                 return fd;
 279
 280         err = do_pin_fd(fd, *argv);
 281
 282         close(fd);
 283         return err;
 284 }
 285
 286 const char *get_fd_type_name(enum bpf_obj_type type)
 287 {
 288         static const char * const names[] = {
 289                 [BPF_OBJ_UNKNOWN]       = "unknown",
 290                 [BPF_OBJ_PROG]          = "prog",
 291                 [BPF_OBJ_MAP]           = "map",
 292         };
 293
 294         if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
 295                 return names[BPF_OBJ_UNKNOWN];
 296
 297         return names[type];
 298 }
 299
 300 int get_fd_type(int fd)
 301 {
 302         char path[PATH_MAX];
 303         char buf[512];
 304         ssize_t n;
 305
 306         snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
 307
 308         n = readlink(path, buf, sizeof(buf));
 309         if (n < 0) {
 310                 p_err("can't read link type: %s", strerror(errno));
 311                 return -1;
 312         }
 313         if (n == sizeof(path)) {
 314                 p_err("can't read link type: path too long!");
 315                 return -1;
 316         }
 317
 318         if (strstr(buf, "bpf-map"))
 319                 return BPF_OBJ_MAP;
 320         else if (strstr(buf, "bpf-prog"))
 321                 return BPF_OBJ_PROG;
 322         else if (strstr(buf, "bpf-link"))
 323                 return BPF_OBJ_LINK;
 324
 325         return BPF_OBJ_UNKNOWN;
 326 }
 327
 328 char *get_fdinfo(int fd, const char *key)
 329 {
 330         char path[PATH_MAX];
 331         char *line = NULL;
 332         size_t line_n = 0;
 333         ssize_t n;
 334         FILE *fdi;
 335
 336         snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
 337
 338         fdi = fopen(path, "r");
 339         if (!fdi)
 340                 return NULL;
 341
 342         while ((n = getline(&line, &line_n, fdi)) > 0) {
 343                 char *value;
 344                 int len;
 345
 346                 if (!strstr(line, key))
 347                         continue;
 348
 349                 fclose(fdi);
 350
 351                 value = strchr(line, '\t');
 352                 if (!value || !value[1]) {
 353                         free(line);
 354                         return NULL;
 355                 }
 356                 value++;
 357
 358                 len = strlen(value);
 359                 memmove(line, value, len);
 360                 line[len - 1] = '\0';
 361
 362                 return line;
 363         }
 364
 365         free(line);
 366         fclose(fdi);
 367         return NULL;
 368 }
 369
 370 void print_data_json(uint8_t *data, size_t len)
 371 {
 372         unsigned int i;
 373
 374         jsonw_start_array(json_wtr);
 375         for (i = 0; i < len; i++)
 376                 jsonw_printf(json_wtr, "%d", data[i]);
 377         jsonw_end_array(json_wtr);
 378 }
 379
 380 void print_hex_data_json(uint8_t *data, size_t len)
 381 {
 382         unsigned int i;
 383
 384         jsonw_start_array(json_wtr);
 385         for (i = 0; i < len; i++)
 386                 jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
 387         jsonw_end_array(json_wtr);
 388 }
 389
 390 /* extra params for nftw cb */
 391 static struct pinned_obj_table *build_fn_table;
 392 static enum bpf_obj_type build_fn_type;
 393
 394 static int do_build_table_cb(const char *fpath, const struct stat *sb,
 395                              int typeflag, struct FTW *ftwbuf)
 396 {
 397         struct bpf_prog_info pinned_info;
 398         __u32 len = sizeof(pinned_info);
 399         struct pinned_obj *obj_node;
 400         enum bpf_obj_type objtype;
 401         int fd, err = 0;
 402
 403         if (typeflag != FTW_F)
 404                 goto out_ret;
 405
 406         fd = open_obj_pinned(fpath, true);
 407         if (fd < 0)
 408                 goto out_ret;
 409
 410         objtype = get_fd_type(fd);
 411         if (objtype != build_fn_type)
 412                 goto out_close;
 413
 414         memset(&pinned_info, 0, sizeof(pinned_info));
 415         if (bpf_obj_get_info_by_fd(fd, &pinned_info, &len))
 416                 goto out_close;
 417
 418         obj_node = calloc(1, sizeof(*obj_node));
 419         if (!obj_node) {
 420                 err = -1;
 421                 goto out_close;
 422         }
 423
 424         obj_node->id = pinned_info.id;
 425         obj_node->path = strdup(fpath);
 426         if (!obj_node->path) {
 427                 err = -1;
 428                 free(obj_node);
 429                 goto out_close;
 430         }
 431
 432         hash_add(build_fn_table->table, &obj_node->hash, obj_node->id);
 433 out_close:
 434         close(fd);
 435 out_ret:
 436         return err;
 437 }
 438
 439 int build_pinned_obj_table(struct pinned_obj_table *tab,
 440                            enum bpf_obj_type type)
 441 {
 442         struct mntent *mntent = NULL;
 443         FILE *mntfile = NULL;
 444         int flags = FTW_PHYS;
 445         int nopenfd = 16;
 446         int err = 0;
 447
 448         mntfile = setmntent("/proc/mounts", "r");
 449         if (!mntfile)
 450                 return -1;
 451
 452         build_fn_table = tab;
 453         build_fn_type = type;
 454
 455         while ((mntent = getmntent(mntfile))) {
 456                 char *path = mntent->mnt_dir;
 457
 458                 if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
 459                         continue;
 460                 err = nftw(path, do_build_table_cb, nopenfd, flags);
 461                 if (err)
 462                         break;
 463         }
 464         fclose(mntfile);
 465         return err;
 466 }
 467
 468 void delete_pinned_obj_table(struct pinned_obj_table *tab)
 469 {
 470         struct pinned_obj *obj;
 471         struct hlist_node *tmp;
 472         unsigned int bkt;
 473
 474         hash_for_each_safe(tab->table, bkt, tmp, obj, hash) {
 475                 hash_del(&obj->hash);
 476                 free(obj->path);
 477                 free(obj);
 478         }
 479 }
 480
 481 unsigned int get_page_size(void)
 482 {
 483         static int result;
 484
 485         if (!result)
 486                 result = getpagesize();
 487         return result;
 488 }
 489
 490 unsigned int get_possible_cpus(void)
 491 {
 492         int cpus = libbpf_num_possible_cpus();
 493
 494         if (cpus < 0) {
 495                 p_err("Can't get # of possible cpus: %s", strerror(-cpus));
 496                 exit(-1);
 497         }
 498         return cpus;
 499 }
 500
 501 static char *
 502 ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
 503 {
 504         struct stat st;
 505         int err;
 506
 507         err = stat("/proc/self/ns/net", &st);
 508         if (err) {
 509                 p_err("Can't stat /proc/self: %s", strerror(errno));
 510                 return NULL;
 511         }
 512
 513         if (st.st_dev != ns_dev || st.st_ino != ns_ino)
 514                 return NULL;
 515
 516         return if_indextoname(ifindex, buf);
 517 }
 518
 519 static int read_sysfs_hex_int(char *path)
 520 {
 521         char vendor_id_buf[8];
 522         int len;
 523         int fd;
 524
 525         fd = open(path, O_RDONLY);
 526         if (fd < 0) {
 527                 p_err("Can't open %s: %s", path, strerror(errno));
 528                 return -1;
 529         }
 530
 531         len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
 532         close(fd);
 533         if (len < 0) {
 534                 p_err("Can't read %s: %s", path, strerror(errno));
 535                 return -1;
 536         }
 537         if (len >= (int)sizeof(vendor_id_buf)) {
 538                 p_err("Value in %s too long", path);
 539                 return -1;
 540         }
 541
 542         vendor_id_buf[len] = 0;
 543
 544         return strtol(vendor_id_buf, NULL, 0);
 545 }
 546
 547 static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
 548 {
 549         char full_path[64];
 550
 551         snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
 552                  devname, entry_name);
 553
 554         return read_sysfs_hex_int(full_path);
 555 }
 556
 557 const char *
 558 ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
 559                       const char **opt)
 560 {
 561         char devname[IF_NAMESIZE];
 562         int vendor_id;
 563         int device_id;
 564
 565         if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
 566                 p_err("Can't get net device name for ifindex %d: %s", ifindex,
 567                       strerror(errno));
 568                 return NULL;
 569         }
 570
 571         vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
 572         if (vendor_id < 0) {
 573                 p_err("Can't get device vendor id for %s", devname);
 574                 return NULL;
 575         }
 576
 577         switch (vendor_id) {
 578         case 0x19ee:
 579                 device_id = read_sysfs_netdev_hex_int(devname, "device");
 580                 if (device_id != 0x4000 &&
 581                     device_id != 0x6000 &&
 582                     device_id != 0x6003)
 583                         p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
 584                 *opt = "ctx4";
 585                 return "NFP-6xxx";
 586         default:
 587                 p_err("Can't get bfd arch name for device vendor id 0x%04x",
 588                       vendor_id);
 589                 return NULL;
 590         }
 591 }
 592
 593 void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
 594 {
 595         char name[IF_NAMESIZE];
 596
 597         if (!ifindex)
 598                 return;
 599
 600         printf("  offloaded_to ");
 601         if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
 602                 printf("%s", name);
 603         else
 604                 printf("ifindex %u ns_dev %llu ns_ino %llu",
 605                        ifindex, ns_dev, ns_inode);
 606 }
 607
 608 void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
 609 {
 610         char name[IF_NAMESIZE];
 611
 612         if (!ifindex)
 613                 return;
 614
 615         jsonw_name(json_wtr, "dev");
 616         jsonw_start_object(json_wtr);
 617         jsonw_uint_field(json_wtr, "ifindex", ifindex);
 618         jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
 619         jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
 620         if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
 621                 jsonw_string_field(json_wtr, "ifname", name);
 622         jsonw_end_object(json_wtr);
 623 }
 624
 625 int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
 626 {
 627         char *endptr;
 628
 629         NEXT_ARGP();
 630
 631         if (*val) {
 632                 p_err("%s already specified", what);
 633                 return -1;
 634         }
 635
 636         *val = strtoul(**argv, &endptr, 0);
 637         if (*endptr) {
 638                 p_err("can't parse %s as %s", **argv, what);
 639                 return -1;
 640         }
 641         NEXT_ARGP();
 642
 643         return 0;
 644 }
 645
 646 int __printf(2, 0)
 647 print_all_levels(__maybe_unused enum libbpf_print_level level,
 648                  const char *format, va_list args)
 649 {
 650         return vfprintf(stderr, format, args);
 651 }
 652
 653 static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)
 654 {
 655         unsigned int id = 0;
 656         int fd, nb_fds = 0;
 657         void *tmp;
 658         int err;
 659
 660         while (true) {
 661                 struct bpf_prog_info info = {};
 662                 __u32 len = sizeof(info);
 663
 664                 err = bpf_prog_get_next_id(id, &id);
 665                 if (err) {
 666                         if (errno != ENOENT) {
 667                                 p_err("%s", strerror(errno));
 668                                 goto err_close_fds;
 669                         }
 670                         return nb_fds;
 671                 }
 672
 673                 fd = bpf_prog_get_fd_by_id(id);
 674                 if (fd < 0) {
 675                         p_err("can't get prog by id (%u): %s",
 676                               id, strerror(errno));
 677                         goto err_close_fds;
 678                 }
 679
 680                 err = bpf_obj_get_info_by_fd(fd, &info, &len);
 681                 if (err) {
 682                         p_err("can't get prog info (%u): %s",
 683                               id, strerror(errno));
 684                         goto err_close_fd;
 685                 }
 686
 687                 if ((tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) ||
 688                     (!tag && strncmp(nametag, info.name, BPF_OBJ_NAME_LEN))) {
 689                         close(fd);
 690                         continue;
 691                 }
 692
 693                 if (nb_fds > 0) {
 694                         tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
 695                         if (!tmp) {
 696                                 p_err("failed to realloc");
 697                                 goto err_close_fd;
 698                         }
 699                         *fds = tmp;
 700                 }
 701                 (*fds)[nb_fds++] = fd;
 702         }
 703
 704 err_close_fd:
 705         close(fd);
 706 err_close_fds:
 707         while (--nb_fds >= 0)
 708                 close((*fds)[nb_fds]);
 709         return -1;
 710 }
 711
 712 int prog_parse_fds(int *argc, char ***argv, int **fds)
 713 {
 714         if (is_prefix(**argv, "id")) {
 715                 unsigned int id;
 716                 char *endptr;
 717
 718                 NEXT_ARGP();
 719
 720                 id = strtoul(**argv, &endptr, 0);
 721                 if (*endptr) {
 722                         p_err("can't parse %s as ID", **argv);
 723                         return -1;
 724                 }
 725                 NEXT_ARGP();
 726
 727                 (*fds)[0] = bpf_prog_get_fd_by_id(id);
 728                 if ((*fds)[0] < 0) {
 729                         p_err("get by id (%u): %s", id, strerror(errno));
 730                         return -1;
 731                 }
 732                 return 1;
 733         } else if (is_prefix(**argv, "tag")) {
 734                 unsigned char tag[BPF_TAG_SIZE];
 735
 736                 NEXT_ARGP();
 737
 738                 if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
 739                            tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
 740                     != BPF_TAG_SIZE) {
 741                         p_err("can't parse tag");
 742                         return -1;
 743                 }
 744                 NEXT_ARGP();
 745
 746                 return prog_fd_by_nametag(tag, fds, true);
 747         } else if (is_prefix(**argv, "name")) {
 748                 char *name;
 749
 750                 NEXT_ARGP();
 751
 752                 name = **argv;
 753                 if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
 754                         p_err("can't parse name");
 755                         return -1;
 756                 }
 757                 NEXT_ARGP();
 758
 759                 return prog_fd_by_nametag(name, fds, false);
 760         } else if (is_prefix(**argv, "pinned")) {
 761                 char *path;
 762
 763                 NEXT_ARGP();
 764
 765                 path = **argv;
 766                 NEXT_ARGP();
 767
 768                 (*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG);
 769                 if ((*fds)[0] < 0)
 770                         return -1;
 771                 return 1;
 772         }
 773
 774         p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);
 775         return -1;
 776 }
 777
 778 int prog_parse_fd(int *argc, char ***argv)
 779 {
 780         int *fds = NULL;
 781         int nb_fds, fd;
 782
 783         fds = malloc(sizeof(int));
 784         if (!fds) {
 785                 p_err("mem alloc failed");
 786                 return -1;
 787         }
 788         nb_fds = prog_parse_fds(argc, argv, &fds);
 789         if (nb_fds != 1) {
 790                 if (nb_fds > 1) {
 791                         p_err("several programs match this handle");
 792                         while (nb_fds--)
 793                                 close(fds[nb_fds]);
 794                 }
 795                 fd = -1;
 796                 goto exit_free;
 797         }
 798
 799         fd = fds[0];
 800 exit_free:
 801         free(fds);
 802         return fd;
 803 }
 804
 805 static int map_fd_by_name(char *name, int **fds)
 806 {
 807         unsigned int id = 0;
 808         int fd, nb_fds = 0;
 809         void *tmp;
 810         int err;
 811
 812         while (true) {
 813                 struct bpf_map_info info = {};
 814                 __u32 len = sizeof(info);
 815
 816                 err = bpf_map_get_next_id(id, &id);
 817                 if (err) {
 818                         if (errno != ENOENT) {
 819                                 p_err("%s", strerror(errno));
 820                                 goto err_close_fds;
 821                         }
 822                         return nb_fds;
 823                 }
 824
 825                 fd = bpf_map_get_fd_by_id(id);
 826                 if (fd < 0) {
 827                         p_err("can't get map by id (%u): %s",
 828                               id, strerror(errno));
 829                         goto err_close_fds;
 830                 }
 831
 832                 err = bpf_obj_get_info_by_fd(fd, &info, &len);
 833                 if (err) {
 834                         p_err("can't get map info (%u): %s",
 835                               id, strerror(errno));
 836                         goto err_close_fd;
 837                 }
 838
 839                 if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {
 840                         close(fd);
 841                         continue;
 842                 }
 843
 844                 if (nb_fds > 0) {
 845                         tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
 846                         if (!tmp) {
 847                                 p_err("failed to realloc");
 848                                 goto err_close_fd;
 849                         }
 850                         *fds = tmp;
 851                 }
 852                 (*fds)[nb_fds++] = fd;
 853         }
 854
 855 err_close_fd:
 856         close(fd);
 857 err_close_fds:
 858         while (--nb_fds >= 0)
 859                 close((*fds)[nb_fds]);
 860         return -1;
 861 }
 862
 863 int map_parse_fds(int *argc, char ***argv, int **fds)
 864 {
 865         if (is_prefix(**argv, "id")) {
 866                 unsigned int id;
 867                 char *endptr;
 868
 869                 NEXT_ARGP();
 870
 871                 id = strtoul(**argv, &endptr, 0);
 872                 if (*endptr) {
 873                         p_err("can't parse %s as ID", **argv);
 874                         return -1;
 875                 }
 876                 NEXT_ARGP();
 877
 878                 (*fds)[0] = bpf_map_get_fd_by_id(id);
 879                 if ((*fds)[0] < 0) {
 880                         p_err("get map by id (%u): %s", id, strerror(errno));
 881                         return -1;
 882                 }
 883                 return 1;
 884         } else if (is_prefix(**argv, "name")) {
 885                 char *name;
 886
 887                 NEXT_ARGP();
 888
 889                 name = **argv;
 890                 if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
 891                         p_err("can't parse name");
 892                         return -1;
 893                 }
 894                 NEXT_ARGP();
 895
 896                 return map_fd_by_name(name, fds);
 897         } else if (is_prefix(**argv, "pinned")) {
 898                 char *path;
 899
 900                 NEXT_ARGP();
 901
 902                 path = **argv;
 903                 NEXT_ARGP();
 904
 905                 (*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP);
 906                 if ((*fds)[0] < 0)
 907                         return -1;
 908                 return 1;
 909         }
 910
 911         p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);
 912         return -1;
 913 }
 914
 915 int map_parse_fd(int *argc, char ***argv)
 916 {
 917         int *fds = NULL;
 918         int nb_fds, fd;
 919
 920         fds = malloc(sizeof(int));
 921         if (!fds) {
 922                 p_err("mem alloc failed");
 923                 return -1;
 924         }
 925         nb_fds = map_parse_fds(argc, argv, &fds);
 926         if (nb_fds != 1) {
 927                 if (nb_fds > 1) {
 928                         p_err("several maps match this handle");
 929                         while (nb_fds--)
 930                                 close(fds[nb_fds]);
 931                 }
 932                 fd = -1;
 933                 goto exit_free;
 934         }
 935
 936         fd = fds[0];
 937 exit_free:
 938         free(fds);
 939         return fd;
 940 }
 941
 942 int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
 943 {
 944         int err;
 945         int fd;
 946
 947         fd = map_parse_fd(argc, argv);
 948         if (fd < 0)
 949                 return -1;
 950
 951         err = bpf_obj_get_info_by_fd(fd, info, info_len);
 952         if (err) {
 953                 p_err("can't get map info: %s", strerror(errno));
 954                 close(fd);
 955                 return err;
 956         }
 957
 958         return fd;
 959 }