bpf: make tc's bpf loader generic and move into lib
This work moves the bpf loader into the iproute2 library and reworks
the tc specific parts into generic code. It's useful as we can then
more easily support new program types by just having the same ELF
loader backend. Joint work with Thomas Graf. I hacked a rough start
of a test suite to make sure nothing breaks [1] and looks all good.
[1] https://github.com/borkmann/clsact/blob/master/test_bpf.sh
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
diff --git a/tc/f_bpf.c b/tc/f_bpf.c
index 665bc66..c4764d8 100644
--- a/tc/f_bpf.c
+++ b/tc/f_bpf.c
@@ -6,7 +6,7 @@
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
- * Authors: Daniel Borkmann <dborkman@redhat.com>
+ * Authors: Daniel Borkmann <daniel@iogearbox.net>
*/
#include <stdio.h>
@@ -15,18 +15,12 @@
#include <linux/bpf.h>
#include "utils.h"
+
#include "tc_util.h"
-#include "tc_bpf.h"
+#include "bpf_util.h"
static const enum bpf_prog_type bpf_type = BPF_PROG_TYPE_SCHED_CLS;
-static const int nla_tbl[BPF_NLA_MAX] = {
- [BPF_NLA_OPS_LEN] = TCA_BPF_OPS_LEN,
- [BPF_NLA_OPS] = TCA_BPF_OPS,
- [BPF_NLA_FD] = TCA_BPF_FD,
- [BPF_NLA_NAME] = TCA_BPF_NAME,
-};
-
static void explain(void)
{
fprintf(stderr, "Usage: ... bpf ...\n");
@@ -52,7 +46,7 @@
fprintf(stderr, "pinned eBPF program.\n");
fprintf(stderr, "\n");
fprintf(stderr, "Where CLS_NAME refers to the section name containing the\n");
- fprintf(stderr, "classifier (default \'%s\').\n", bpf_default_section(bpf_type));
+ fprintf(stderr, "classifier (default \'%s\').\n", bpf_prog_to_default_section(bpf_type));
fprintf(stderr, "\n");
fprintf(stderr, "Where UDS_FILE points to a unix domain socket file in order\n");
fprintf(stderr, "to hand off control of all created eBPF maps to an agent.\n");
@@ -61,6 +55,24 @@
fprintf(stderr, "NOTE: CLASSID is parsed as hexadecimal input.\n");
}
+static void bpf_cbpf_cb(void *nl, const struct sock_filter *ops, int ops_len)
+{
+ addattr16(nl, MAX_MSG, TCA_BPF_OPS_LEN, ops_len);
+ addattr_l(nl, MAX_MSG, TCA_BPF_OPS, ops,
+ ops_len * sizeof(struct sock_filter));
+}
+
+static void bpf_ebpf_cb(void *nl, int fd, const char *annotation)
+{
+ addattr32(nl, MAX_MSG, TCA_BPF_FD, fd);
+ addattrstrz(nl, MAX_MSG, TCA_BPF_NAME, annotation);
+}
+
+static const struct bpf_cfg_ops bpf_cb_ops = {
+ .cbpf_cb = bpf_cbpf_cb,
+ .ebpf_cb = bpf_ebpf_cb,
+};
+
static int bpf_parse_opt(struct filter_util *qu, char *handle,
int argc, char **argv, struct nlmsghdr *n)
{
@@ -68,6 +80,7 @@
struct tcmsg *t = NLMSG_DATA(n);
unsigned int bpf_gen_flags = 0;
unsigned int bpf_flags = 0;
+ struct bpf_cfg_in cfg = {};
bool seen_run = false;
struct rtattr *tail;
int ret = 0;
@@ -90,11 +103,17 @@
NEXT_ARG();
opt_bpf:
seen_run = true;
- if (bpf_parse_common(&argc, &argv, nla_tbl, bpf_type,
- &bpf_obj, &bpf_uds_name, n)) {
- fprintf(stderr, "Failed to retrieve (e)BPF data!\n");
+ cfg.argc = argc;
+ cfg.argv = argv;
+
+ if (bpf_parse_common(bpf_type, &cfg, &bpf_cb_ops, n))
return -1;
- }
+
+ argc = cfg.argc;
+ argv = cfg.argv;
+
+ bpf_obj = cfg.object;
+ bpf_uds_name = cfg.uds;
} else if (matches(*argv, "classid") == 0 ||
matches(*argv, "flowid") == 0) {
unsigned int handle;
@@ -143,7 +162,7 @@
if (bpf_gen_flags)
addattr32(n, MAX_MSG, TCA_BPF_FLAGS_GEN, bpf_gen_flags);
- if (bpf_obj && bpf_flags)
+ if (bpf_flags)
addattr32(n, MAX_MSG, TCA_BPF_FLAGS, bpf_flags);
tail->rta_len = (((void *)n) + n->nlmsg_len) - (void *)tail;
@@ -175,8 +194,6 @@
if (tb[TCA_BPF_NAME])
fprintf(f, "%s ", rta_getattr_str(tb[TCA_BPF_NAME]));
- else if (tb[TCA_BPF_FD])
- fprintf(f, "pfd %u ", rta_getattr_u32(tb[TCA_BPF_FD]));
if (tb[TCA_BPF_FLAGS]) {
unsigned int flags = rta_getattr_u32(tb[TCA_BPF_FLAGS]);
@@ -195,20 +212,17 @@
fprintf(f, "skip_sw ");
}
- if (tb[TCA_BPF_OPS] && tb[TCA_BPF_OPS_LEN]) {
+ if (tb[TCA_BPF_OPS] && tb[TCA_BPF_OPS_LEN])
bpf_print_ops(f, tb[TCA_BPF_OPS],
rta_getattr_u16(tb[TCA_BPF_OPS_LEN]));
- fprintf(f, "\n");
- }
if (tb[TCA_BPF_POLICE]) {
fprintf(f, "\n");
tc_print_police(f, tb[TCA_BPF_POLICE]);
}
- if (tb[TCA_BPF_ACT]) {
+ if (tb[TCA_BPF_ACT])
tc_print_action(f, tb[TCA_BPF_ACT]);
- }
return 0;
}