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v6.8
  1// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
  2/* Copyright (c) 2019 Netronome Systems, Inc. */
  3
  4#include <errno.h>
  5#include <fcntl.h>
  6#include <string.h>
  7#include <stdlib.h>
  8#include <unistd.h>
  9#include <net/if.h>
 10#include <sys/utsname.h>
 11
 12#include <linux/btf.h>
 13#include <linux/filter.h>
 14#include <linux/kernel.h>
 15#include <linux/version.h>
 16
 17#include "bpf.h"
 18#include "libbpf.h"
 19#include "libbpf_internal.h"
 20
 21/* On Ubuntu LINUX_VERSION_CODE doesn't correspond to info.release,
 22 * but Ubuntu provides /proc/version_signature file, as described at
 23 * https://ubuntu.com/kernel, with an example contents below, which we
 24 * can use to get a proper LINUX_VERSION_CODE.
 25 *
 26 *   Ubuntu 5.4.0-12.15-generic 5.4.8
 27 *
 28 * In the above, 5.4.8 is what kernel is actually expecting, while
 29 * uname() call will return 5.4.0 in info.release.
 30 */
 31static __u32 get_ubuntu_kernel_version(void)
 32{
 33	const char *ubuntu_kver_file = "/proc/version_signature";
 34	__u32 major, minor, patch;
 35	int ret;
 36	FILE *f;
 37
 38	if (faccessat(AT_FDCWD, ubuntu_kver_file, R_OK, AT_EACCESS) != 0)
 39		return 0;
 40
 41	f = fopen(ubuntu_kver_file, "re");
 42	if (!f)
 43		return 0;
 44
 45	ret = fscanf(f, "%*s %*s %u.%u.%u\n", &major, &minor, &patch);
 46	fclose(f);
 47	if (ret != 3)
 48		return 0;
 49
 50	return KERNEL_VERSION(major, minor, patch);
 51}
 52
 53/* On Debian LINUX_VERSION_CODE doesn't correspond to info.release.
 54 * Instead, it is provided in info.version. An example content of
 55 * Debian 10 looks like the below.
 56 *
 57 *   utsname::release   4.19.0-22-amd64
 58 *   utsname::version   #1 SMP Debian 4.19.260-1 (2022-09-29)
 59 *
 60 * In the above, 4.19.260 is what kernel is actually expecting, while
 61 * uname() call will return 4.19.0 in info.release.
 62 */
 63static __u32 get_debian_kernel_version(struct utsname *info)
 64{
 65	__u32 major, minor, patch;
 66	char *p;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 67
 68	p = strstr(info->version, "Debian ");
 69	if (!p) {
 70		/* This is not a Debian kernel. */
 71		return 0;
 72	}
 73
 74	if (sscanf(p, "Debian %u.%u.%u", &major, &minor, &patch) != 3)
 75		return 0;
 76
 77	return KERNEL_VERSION(major, minor, patch);
 78}
 79
 80__u32 get_kernel_version(void)
 81{
 82	__u32 major, minor, patch, version;
 83	struct utsname info;
 84
 85	/* Check if this is an Ubuntu kernel. */
 86	version = get_ubuntu_kernel_version();
 87	if (version != 0)
 88		return version;
 89
 90	uname(&info);
 91
 92	/* Check if this is a Debian kernel. */
 93	version = get_debian_kernel_version(&info);
 94	if (version != 0)
 95		return version;
 96
 97	if (sscanf(info.release, "%u.%u.%u", &major, &minor, &patch) != 3)
 
 98		return 0;
 99
100	return KERNEL_VERSION(major, minor, patch);
101}
102
103static int probe_prog_load(enum bpf_prog_type prog_type,
104			   const struct bpf_insn *insns, size_t insns_cnt,
105			   char *log_buf, size_t log_buf_sz)
106{
107	LIBBPF_OPTS(bpf_prog_load_opts, opts,
108		.log_buf = log_buf,
109		.log_size = log_buf_sz,
110		.log_level = log_buf ? 1 : 0,
111	);
112	int fd, err, exp_err = 0;
113	const char *exp_msg = NULL;
114	char buf[4096];
115
116	switch (prog_type) {
117	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
118		opts.expected_attach_type = BPF_CGROUP_INET4_CONNECT;
119		break;
120	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
121		opts.expected_attach_type = BPF_CGROUP_GETSOCKOPT;
122		break;
123	case BPF_PROG_TYPE_SK_LOOKUP:
124		opts.expected_attach_type = BPF_SK_LOOKUP;
125		break;
126	case BPF_PROG_TYPE_KPROBE:
127		opts.kern_version = get_kernel_version();
128		break;
129	case BPF_PROG_TYPE_LIRC_MODE2:
130		opts.expected_attach_type = BPF_LIRC_MODE2;
131		break;
132	case BPF_PROG_TYPE_TRACING:
133	case BPF_PROG_TYPE_LSM:
134		opts.log_buf = buf;
135		opts.log_size = sizeof(buf);
136		opts.log_level = 1;
137		if (prog_type == BPF_PROG_TYPE_TRACING)
138			opts.expected_attach_type = BPF_TRACE_FENTRY;
139		else
140			opts.expected_attach_type = BPF_MODIFY_RETURN;
141		opts.attach_btf_id = 1;
142
143		exp_err = -EINVAL;
144		exp_msg = "attach_btf_id 1 is not a function";
145		break;
146	case BPF_PROG_TYPE_EXT:
147		opts.log_buf = buf;
148		opts.log_size = sizeof(buf);
149		opts.log_level = 1;
150		opts.attach_btf_id = 1;
151
152		exp_err = -EINVAL;
153		exp_msg = "Cannot replace kernel functions";
154		break;
155	case BPF_PROG_TYPE_SYSCALL:
156		opts.prog_flags = BPF_F_SLEEPABLE;
157		break;
158	case BPF_PROG_TYPE_STRUCT_OPS:
159		exp_err = -524; /* -ENOTSUPP */
160		break;
161	case BPF_PROG_TYPE_UNSPEC:
162	case BPF_PROG_TYPE_SOCKET_FILTER:
163	case BPF_PROG_TYPE_SCHED_CLS:
164	case BPF_PROG_TYPE_SCHED_ACT:
165	case BPF_PROG_TYPE_TRACEPOINT:
166	case BPF_PROG_TYPE_XDP:
167	case BPF_PROG_TYPE_PERF_EVENT:
168	case BPF_PROG_TYPE_CGROUP_SKB:
169	case BPF_PROG_TYPE_CGROUP_SOCK:
170	case BPF_PROG_TYPE_LWT_IN:
171	case BPF_PROG_TYPE_LWT_OUT:
172	case BPF_PROG_TYPE_LWT_XMIT:
173	case BPF_PROG_TYPE_SOCK_OPS:
174	case BPF_PROG_TYPE_SK_SKB:
175	case BPF_PROG_TYPE_CGROUP_DEVICE:
176	case BPF_PROG_TYPE_SK_MSG:
177	case BPF_PROG_TYPE_RAW_TRACEPOINT:
178	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
179	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
 
180	case BPF_PROG_TYPE_SK_REUSEPORT:
181	case BPF_PROG_TYPE_FLOW_DISSECTOR:
182	case BPF_PROG_TYPE_CGROUP_SYSCTL:
183		break;
184	case BPF_PROG_TYPE_NETFILTER:
185		opts.expected_attach_type = BPF_NETFILTER;
186		break;
187	default:
188		return -EOPNOTSUPP;
189	}
190
191	fd = bpf_prog_load(prog_type, NULL, "GPL", insns, insns_cnt, &opts);
192	err = -errno;
 
 
 
 
 
193	if (fd >= 0)
194		close(fd);
195	if (exp_err) {
196		if (fd >= 0 || err != exp_err)
197			return 0;
198		if (exp_msg && !strstr(buf, exp_msg))
199			return 0;
200		return 1;
201	}
202	return fd >= 0 ? 1 : 0;
203}
204
205int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts)
206{
207	struct bpf_insn insns[] = {
208		BPF_MOV64_IMM(BPF_REG_0, 0),
209		BPF_EXIT_INSN()
210	};
211	const size_t insn_cnt = ARRAY_SIZE(insns);
212	int ret;
213
214	if (opts)
215		return libbpf_err(-EINVAL);
 
 
 
 
216
217	ret = probe_prog_load(prog_type, insns, insn_cnt, NULL, 0);
218	return libbpf_err(ret);
219}
220
221int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
222			 const char *str_sec, size_t str_len)
223{
224	struct btf_header hdr = {
225		.magic = BTF_MAGIC,
226		.version = BTF_VERSION,
227		.hdr_len = sizeof(struct btf_header),
228		.type_len = types_len,
229		.str_off = types_len,
230		.str_len = str_len,
231	};
232	int btf_fd, btf_len;
233	__u8 *raw_btf;
234
235	btf_len = hdr.hdr_len + hdr.type_len + hdr.str_len;
236	raw_btf = malloc(btf_len);
237	if (!raw_btf)
238		return -ENOMEM;
239
240	memcpy(raw_btf, &hdr, sizeof(hdr));
241	memcpy(raw_btf + hdr.hdr_len, raw_types, hdr.type_len);
242	memcpy(raw_btf + hdr.hdr_len + hdr.type_len, str_sec, hdr.str_len);
243
244	btf_fd = bpf_btf_load(raw_btf, btf_len, NULL);
245
246	free(raw_btf);
247	return btf_fd;
248}
249
250static int load_local_storage_btf(void)
251{
252	const char strs[] = "\0bpf_spin_lock\0val\0cnt\0l";
253	/* struct bpf_spin_lock {
254	 *   int val;
255	 * };
256	 * struct val {
257	 *   int cnt;
258	 *   struct bpf_spin_lock l;
259	 * };
260	 */
261	__u32 types[] = {
262		/* int */
263		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
264		/* struct bpf_spin_lock */                      /* [2] */
265		BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 1), 4),
266		BTF_MEMBER_ENC(15, 1, 0), /* int val; */
267		/* struct val */                                /* [3] */
268		BTF_TYPE_ENC(15, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), 8),
269		BTF_MEMBER_ENC(19, 1, 0), /* int cnt; */
270		BTF_MEMBER_ENC(23, 2, 32),/* struct bpf_spin_lock l; */
271	};
272
273	return libbpf__load_raw_btf((char *)types, sizeof(types),
274				     strs, sizeof(strs));
275}
276
277static int probe_map_create(enum bpf_map_type map_type)
278{
279	LIBBPF_OPTS(bpf_map_create_opts, opts);
280	int key_size, value_size, max_entries;
281	__u32 btf_key_type_id = 0, btf_value_type_id = 0;
282	int fd = -1, btf_fd = -1, fd_inner = -1, exp_err = 0, err = 0;
 
283
284	key_size	= sizeof(__u32);
285	value_size	= sizeof(__u32);
286	max_entries	= 1;
 
287
288	switch (map_type) {
289	case BPF_MAP_TYPE_STACK_TRACE:
290		value_size	= sizeof(__u64);
291		break;
292	case BPF_MAP_TYPE_LPM_TRIE:
293		key_size	= sizeof(__u64);
294		value_size	= sizeof(__u64);
295		opts.map_flags	= BPF_F_NO_PREALLOC;
296		break;
297	case BPF_MAP_TYPE_CGROUP_STORAGE:
298	case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE:
299		key_size	= sizeof(struct bpf_cgroup_storage_key);
300		value_size	= sizeof(__u64);
301		max_entries	= 0;
302		break;
303	case BPF_MAP_TYPE_QUEUE:
304	case BPF_MAP_TYPE_STACK:
305		key_size	= 0;
306		break;
307	case BPF_MAP_TYPE_SK_STORAGE:
308	case BPF_MAP_TYPE_INODE_STORAGE:
309	case BPF_MAP_TYPE_TASK_STORAGE:
310	case BPF_MAP_TYPE_CGRP_STORAGE:
311		btf_key_type_id = 1;
312		btf_value_type_id = 3;
313		value_size = 8;
314		max_entries = 0;
315		opts.map_flags = BPF_F_NO_PREALLOC;
316		btf_fd = load_local_storage_btf();
317		if (btf_fd < 0)
318			return btf_fd;
319		break;
320	case BPF_MAP_TYPE_RINGBUF:
321	case BPF_MAP_TYPE_USER_RINGBUF:
322		key_size = 0;
323		value_size = 0;
324		max_entries = sysconf(_SC_PAGE_SIZE);
325		break;
326	case BPF_MAP_TYPE_STRUCT_OPS:
327		/* we'll get -ENOTSUPP for invalid BTF type ID for struct_ops */
328		opts.btf_vmlinux_value_type_id = 1;
329		exp_err = -524; /* -ENOTSUPP */
330		break;
331	case BPF_MAP_TYPE_BLOOM_FILTER:
332		key_size = 0;
333		max_entries = 1;
334		break;
 
335	case BPF_MAP_TYPE_HASH:
336	case BPF_MAP_TYPE_ARRAY:
337	case BPF_MAP_TYPE_PROG_ARRAY:
338	case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
339	case BPF_MAP_TYPE_PERCPU_HASH:
340	case BPF_MAP_TYPE_PERCPU_ARRAY:
341	case BPF_MAP_TYPE_CGROUP_ARRAY:
342	case BPF_MAP_TYPE_LRU_HASH:
343	case BPF_MAP_TYPE_LRU_PERCPU_HASH:
344	case BPF_MAP_TYPE_ARRAY_OF_MAPS:
345	case BPF_MAP_TYPE_HASH_OF_MAPS:
346	case BPF_MAP_TYPE_DEVMAP:
347	case BPF_MAP_TYPE_DEVMAP_HASH:
348	case BPF_MAP_TYPE_SOCKMAP:
349	case BPF_MAP_TYPE_CPUMAP:
350	case BPF_MAP_TYPE_XSKMAP:
351	case BPF_MAP_TYPE_SOCKHASH:
352	case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY:
353		break;
354	case BPF_MAP_TYPE_UNSPEC:
355	default:
356		return -EOPNOTSUPP;
357	}
358
359	if (map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
360	    map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
361		fd_inner = bpf_map_create(BPF_MAP_TYPE_HASH, NULL,
362					  sizeof(__u32), sizeof(__u32), 1, NULL);
363		if (fd_inner < 0)
364			goto cleanup;
 
365
366		opts.inner_map_fd = fd_inner;
367	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
368
369	if (btf_fd >= 0) {
370		opts.btf_fd = btf_fd;
371		opts.btf_key_type_id = btf_key_type_id;
372		opts.btf_value_type_id = btf_value_type_id;
373	}
374
375	fd = bpf_map_create(map_type, NULL, key_size, value_size, max_entries, &opts);
376	err = -errno;
377
378cleanup:
379	if (fd >= 0)
380		close(fd);
381	if (fd_inner >= 0)
382		close(fd_inner);
383	if (btf_fd >= 0)
384		close(btf_fd);
385
386	if (exp_err)
387		return fd < 0 && err == exp_err ? 1 : 0;
388	else
389		return fd >= 0 ? 1 : 0;
390}
391
392int libbpf_probe_bpf_map_type(enum bpf_map_type map_type, const void *opts)
 
393{
394	int ret;
395
396	if (opts)
397		return libbpf_err(-EINVAL);
398
399	ret = probe_map_create(map_type);
400	return libbpf_err(ret);
401}
402
403int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id helper_id,
404			    const void *opts)
405{
406	struct bpf_insn insns[] = {
407		BPF_EMIT_CALL((__u32)helper_id),
408		BPF_EXIT_INSN(),
409	};
410	const size_t insn_cnt = ARRAY_SIZE(insns);
411	char buf[4096];
412	int ret;
413
414	if (opts)
415		return libbpf_err(-EINVAL);
416
417	/* we can't successfully load all prog types to check for BPF helper
418	 * support, so bail out with -EOPNOTSUPP error
419	 */
420	switch (prog_type) {
421	case BPF_PROG_TYPE_TRACING:
422	case BPF_PROG_TYPE_EXT:
423	case BPF_PROG_TYPE_LSM:
424	case BPF_PROG_TYPE_STRUCT_OPS:
425		return -EOPNOTSUPP;
426	default:
427		break;
428	}
429
430	buf[0] = '\0';
431	ret = probe_prog_load(prog_type, insns, insn_cnt, buf, sizeof(buf));
432	if (ret < 0)
433		return libbpf_err(ret);
434
435	/* If BPF verifier doesn't recognize BPF helper ID (enum bpf_func_id)
436	 * at all, it will emit something like "invalid func unknown#181".
437	 * If BPF verifier recognizes BPF helper but it's not supported for
438	 * given BPF program type, it will emit "unknown func bpf_sys_bpf#166".
439	 * In both cases, provided combination of BPF program type and BPF
440	 * helper is not supported by the kernel.
441	 * In all other cases, probe_prog_load() above will either succeed (e.g.,
442	 * because BPF helper happens to accept no input arguments or it
443	 * accepts one input argument and initial PTR_TO_CTX is fine for
444	 * that), or we'll get some more specific BPF verifier error about
445	 * some unsatisfied conditions.
446	 */
447	if (ret == 0 && (strstr(buf, "invalid func ") || strstr(buf, "unknown func ")))
448		return 0;
449	return 1; /* assume supported */
450}
v5.4
  1// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
  2/* Copyright (c) 2019 Netronome Systems, Inc. */
  3
  4#include <errno.h>
  5#include <fcntl.h>
  6#include <string.h>
  7#include <stdlib.h>
  8#include <unistd.h>
  9#include <net/if.h>
 10#include <sys/utsname.h>
 11
 12#include <linux/btf.h>
 13#include <linux/filter.h>
 14#include <linux/kernel.h>
 
 15
 16#include "bpf.h"
 17#include "libbpf.h"
 18#include "libbpf_internal.h"
 19
 20static bool grep(const char *buffer, const char *pattern)
 
 
 
 
 
 
 
 
 
 
 21{
 22	return !!strstr(buffer, pattern);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 23}
 24
 25static int get_vendor_id(int ifindex)
 
 
 
 
 
 
 
 
 
 
 26{
 27	char ifname[IF_NAMESIZE], path[64], buf[8];
 28	ssize_t len;
 29	int fd;
 30
 31	if (!if_indextoname(ifindex, ifname))
 32		return -1;
 33
 34	snprintf(path, sizeof(path), "/sys/class/net/%s/device/vendor", ifname);
 35
 36	fd = open(path, O_RDONLY);
 37	if (fd < 0)
 38		return -1;
 39
 40	len = read(fd, buf, sizeof(buf));
 41	close(fd);
 42	if (len < 0)
 43		return -1;
 44	if (len >= (ssize_t)sizeof(buf))
 45		return -1;
 46	buf[len] = '\0';
 47
 48	return strtol(buf, NULL, 0);
 
 
 
 
 
 
 
 
 
 49}
 50
 51static int get_kernel_version(void)
 52{
 53	int version, subversion, patchlevel;
 54	struct utsname utsn;
 55
 56	/* Return 0 on failure, and attempt to probe with empty kversion */
 57	if (uname(&utsn))
 58		return 0;
 
 
 
 
 
 
 
 
 59
 60	if (sscanf(utsn.release, "%d.%d.%d",
 61		   &version, &subversion, &patchlevel) != 3)
 62		return 0;
 63
 64	return (version << 16) + (subversion << 8) + patchlevel;
 65}
 66
 67static void
 68probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns,
 69	   size_t insns_cnt, char *buf, size_t buf_len, __u32 ifindex)
 70{
 71	struct bpf_load_program_attr xattr = {};
 72	int fd;
 
 
 
 
 
 
 73
 74	switch (prog_type) {
 75	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
 76		xattr.expected_attach_type = BPF_CGROUP_INET4_CONNECT;
 
 
 
 
 
 
 77		break;
 78	case BPF_PROG_TYPE_KPROBE:
 79		xattr.kern_version = get_kernel_version();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 80		break;
 81	case BPF_PROG_TYPE_UNSPEC:
 82	case BPF_PROG_TYPE_SOCKET_FILTER:
 83	case BPF_PROG_TYPE_SCHED_CLS:
 84	case BPF_PROG_TYPE_SCHED_ACT:
 85	case BPF_PROG_TYPE_TRACEPOINT:
 86	case BPF_PROG_TYPE_XDP:
 87	case BPF_PROG_TYPE_PERF_EVENT:
 88	case BPF_PROG_TYPE_CGROUP_SKB:
 89	case BPF_PROG_TYPE_CGROUP_SOCK:
 90	case BPF_PROG_TYPE_LWT_IN:
 91	case BPF_PROG_TYPE_LWT_OUT:
 92	case BPF_PROG_TYPE_LWT_XMIT:
 93	case BPF_PROG_TYPE_SOCK_OPS:
 94	case BPF_PROG_TYPE_SK_SKB:
 95	case BPF_PROG_TYPE_CGROUP_DEVICE:
 96	case BPF_PROG_TYPE_SK_MSG:
 97	case BPF_PROG_TYPE_RAW_TRACEPOINT:
 98	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
 99	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
100	case BPF_PROG_TYPE_LIRC_MODE2:
101	case BPF_PROG_TYPE_SK_REUSEPORT:
102	case BPF_PROG_TYPE_FLOW_DISSECTOR:
103	case BPF_PROG_TYPE_CGROUP_SYSCTL:
104	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
 
 
 
105	default:
106		break;
107	}
108
109	xattr.prog_type = prog_type;
110	xattr.insns = insns;
111	xattr.insns_cnt = insns_cnt;
112	xattr.license = "GPL";
113	xattr.prog_ifindex = ifindex;
114
115	fd = bpf_load_program_xattr(&xattr, buf, buf_len);
116	if (fd >= 0)
117		close(fd);
 
 
 
 
 
 
 
 
118}
119
120bool bpf_probe_prog_type(enum bpf_prog_type prog_type, __u32 ifindex)
121{
122	struct bpf_insn insns[2] = {
123		BPF_MOV64_IMM(BPF_REG_0, 0),
124		BPF_EXIT_INSN()
125	};
 
 
126
127	if (ifindex && prog_type == BPF_PROG_TYPE_SCHED_CLS)
128		/* nfp returns -EINVAL on exit(0) with TC offload */
129		insns[0].imm = 2;
130
131	errno = 0;
132	probe_load(prog_type, insns, ARRAY_SIZE(insns), NULL, 0, ifindex);
133
134	return errno != EINVAL && errno != EOPNOTSUPP;
 
135}
136
137int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
138			 const char *str_sec, size_t str_len)
139{
140	struct btf_header hdr = {
141		.magic = BTF_MAGIC,
142		.version = BTF_VERSION,
143		.hdr_len = sizeof(struct btf_header),
144		.type_len = types_len,
145		.str_off = types_len,
146		.str_len = str_len,
147	};
148	int btf_fd, btf_len;
149	__u8 *raw_btf;
150
151	btf_len = hdr.hdr_len + hdr.type_len + hdr.str_len;
152	raw_btf = malloc(btf_len);
153	if (!raw_btf)
154		return -ENOMEM;
155
156	memcpy(raw_btf, &hdr, sizeof(hdr));
157	memcpy(raw_btf + hdr.hdr_len, raw_types, hdr.type_len);
158	memcpy(raw_btf + hdr.hdr_len + hdr.type_len, str_sec, hdr.str_len);
159
160	btf_fd = bpf_load_btf(raw_btf, btf_len, NULL, 0, false);
161
162	free(raw_btf);
163	return btf_fd;
164}
165
166static int load_sk_storage_btf(void)
167{
168	const char strs[] = "\0bpf_spin_lock\0val\0cnt\0l";
169	/* struct bpf_spin_lock {
170	 *   int val;
171	 * };
172	 * struct val {
173	 *   int cnt;
174	 *   struct bpf_spin_lock l;
175	 * };
176	 */
177	__u32 types[] = {
178		/* int */
179		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
180		/* struct bpf_spin_lock */                      /* [2] */
181		BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 1), 4),
182		BTF_MEMBER_ENC(15, 1, 0), /* int val; */
183		/* struct val */                                /* [3] */
184		BTF_TYPE_ENC(15, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), 8),
185		BTF_MEMBER_ENC(19, 1, 0), /* int cnt; */
186		BTF_MEMBER_ENC(23, 2, 32),/* struct bpf_spin_lock l; */
187	};
188
189	return libbpf__load_raw_btf((char *)types, sizeof(types),
190				     strs, sizeof(strs));
191}
192
193bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex)
194{
195	int key_size, value_size, max_entries, map_flags;
 
196	__u32 btf_key_type_id = 0, btf_value_type_id = 0;
197	struct bpf_create_map_attr attr = {};
198	int fd = -1, btf_fd = -1, fd_inner;
199
200	key_size	= sizeof(__u32);
201	value_size	= sizeof(__u32);
202	max_entries	= 1;
203	map_flags	= 0;
204
205	switch (map_type) {
206	case BPF_MAP_TYPE_STACK_TRACE:
207		value_size	= sizeof(__u64);
208		break;
209	case BPF_MAP_TYPE_LPM_TRIE:
210		key_size	= sizeof(__u64);
211		value_size	= sizeof(__u64);
212		map_flags	= BPF_F_NO_PREALLOC;
213		break;
214	case BPF_MAP_TYPE_CGROUP_STORAGE:
215	case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE:
216		key_size	= sizeof(struct bpf_cgroup_storage_key);
217		value_size	= sizeof(__u64);
218		max_entries	= 0;
219		break;
220	case BPF_MAP_TYPE_QUEUE:
221	case BPF_MAP_TYPE_STACK:
222		key_size	= 0;
223		break;
224	case BPF_MAP_TYPE_SK_STORAGE:
 
 
 
225		btf_key_type_id = 1;
226		btf_value_type_id = 3;
227		value_size = 8;
228		max_entries = 0;
229		map_flags = BPF_F_NO_PREALLOC;
230		btf_fd = load_sk_storage_btf();
231		if (btf_fd < 0)
232			return false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
233		break;
234	case BPF_MAP_TYPE_UNSPEC:
235	case BPF_MAP_TYPE_HASH:
236	case BPF_MAP_TYPE_ARRAY:
237	case BPF_MAP_TYPE_PROG_ARRAY:
238	case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
239	case BPF_MAP_TYPE_PERCPU_HASH:
240	case BPF_MAP_TYPE_PERCPU_ARRAY:
241	case BPF_MAP_TYPE_CGROUP_ARRAY:
242	case BPF_MAP_TYPE_LRU_HASH:
243	case BPF_MAP_TYPE_LRU_PERCPU_HASH:
244	case BPF_MAP_TYPE_ARRAY_OF_MAPS:
245	case BPF_MAP_TYPE_HASH_OF_MAPS:
246	case BPF_MAP_TYPE_DEVMAP:
247	case BPF_MAP_TYPE_DEVMAP_HASH:
248	case BPF_MAP_TYPE_SOCKMAP:
249	case BPF_MAP_TYPE_CPUMAP:
250	case BPF_MAP_TYPE_XSKMAP:
251	case BPF_MAP_TYPE_SOCKHASH:
252	case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY:
 
 
253	default:
254		break;
255	}
256
257	if (map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
258	    map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
259		/* TODO: probe for device, once libbpf has a function to create
260		 * map-in-map for offload
261		 */
262		if (ifindex)
263			return false;
264
265		fd_inner = bpf_create_map(BPF_MAP_TYPE_HASH,
266					  sizeof(__u32), sizeof(__u32), 1, 0);
267		if (fd_inner < 0)
268			return false;
269		fd = bpf_create_map_in_map(map_type, NULL, sizeof(__u32),
270					   fd_inner, 1, 0);
271		close(fd_inner);
272	} else {
273		/* Note: No other restriction on map type probes for offload */
274		attr.map_type = map_type;
275		attr.key_size = key_size;
276		attr.value_size = value_size;
277		attr.max_entries = max_entries;
278		attr.map_flags = map_flags;
279		attr.map_ifindex = ifindex;
280		if (btf_fd >= 0) {
281			attr.btf_fd = btf_fd;
282			attr.btf_key_type_id = btf_key_type_id;
283			attr.btf_value_type_id = btf_value_type_id;
284		}
285
286		fd = bpf_create_map_xattr(&attr);
 
 
 
287	}
 
 
 
 
 
288	if (fd >= 0)
289		close(fd);
 
 
290	if (btf_fd >= 0)
291		close(btf_fd);
292
293	return fd >= 0;
 
 
 
294}
295
296bool bpf_probe_helper(enum bpf_func_id id, enum bpf_prog_type prog_type,
297		      __u32 ifindex)
298{
299	struct bpf_insn insns[2] = {
300		BPF_EMIT_CALL(id),
301		BPF_EXIT_INSN()
 
 
 
 
 
 
 
 
 
 
 
 
302	};
303	char buf[4096] = {};
304	bool res;
 
305
306	probe_load(prog_type, insns, ARRAY_SIZE(insns), buf, sizeof(buf),
307		   ifindex);
308	res = !grep(buf, "invalid func ") && !grep(buf, "unknown func ");
309
310	if (ifindex) {
311		switch (get_vendor_id(ifindex)) {
312		case 0x19ee: /* Netronome specific */
313			res = res && !grep(buf, "not supported by FW") &&
314				!grep(buf, "unsupported function id");
315			break;
316		default:
317			break;
318		}
 
319	}
320
321	return res;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
322}