Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0dcbbf67 authored by John Fastabend's avatar John Fastabend Committed by Daniel Borkmann
Browse files

bpf: sockmap sample test for bpf_msg_pull_data



This adds an option to test the msg_pull_data helper. This
uses two options txmsg_start and txmsg_end to let the user
specify start and end bytes to pull.

The options can be used with txmsg_apply, txmsg_cork options
as well as with any of the basic tests, txmsg, txmsg_redir and
txmsg_drop (plus noisy variants) to run pull_data inline with
those tests. By giving user direct control over the variables
we can easily do negative testing as well as positive tests.

Signed-off-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
parent e6373ce7
Loading
Loading
Loading
Loading
+65 −14
Original line number Diff line number Diff line
@@ -71,6 +71,14 @@ struct bpf_map_def SEC("maps") sock_cork_bytes = {
	.max_entries = 1
};

struct bpf_map_def SEC("maps") sock_pull_bytes = {
	.type = BPF_MAP_TYPE_ARRAY,
	.key_size = sizeof(int),
	.value_size = sizeof(int),
	.max_entries = 2
};


SEC("sk_skb1")
int bpf_prog1(struct __sk_buff *skb)
{
@@ -137,7 +145,8 @@ int bpf_sockmap(struct bpf_sock_ops *skops)
SEC("sk_msg1")
int bpf_prog4(struct sk_msg_md *msg)
{
	int *bytes, zero = 0;
	int *bytes, zero = 0, one = 1;
	int *start, *end;

	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes)
@@ -145,15 +154,18 @@ int bpf_prog4(struct sk_msg_md *msg)
	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
	if (bytes)
		bpf_msg_cork_bytes(msg, *bytes);
	start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
	end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
	if (start && end)
		bpf_msg_pull_data(msg, *start, *end, 0);
	return SK_PASS;
}

SEC("sk_msg2")
int bpf_prog5(struct sk_msg_md *msg)
{
	void *data_end = (void *)(long) msg->data_end;
	void *data = (void *)(long) msg->data;
	int *bytes, err1 = -1, err2 = -1, zero = 0;
	int err1 = -1, err2 = -1, zero = 0, one = 1;
	int *bytes, *start, *end, len1, len2;

	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes)
@@ -161,17 +173,32 @@ int bpf_prog5(struct sk_msg_md *msg)
	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
	if (bytes)
		err2 = bpf_msg_cork_bytes(msg, *bytes);
	len1 = (__u64)msg->data_end - (__u64)msg->data;
	start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
	end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
	if (start && end) {
		int err;

		bpf_printk("sk_msg2: pull(%i:%i)\n",
			   start ? *start : 0, end ? *end : 0);
		err = bpf_msg_pull_data(msg, *start, *end, 0);
		if (err)
			bpf_printk("sk_msg2: pull_data err %i\n",
				   err);
		len2 = (__u64)msg->data_end - (__u64)msg->data;
		bpf_printk("sk_msg2: length update %i->%i\n",
			   len1, len2);
	}
	bpf_printk("sk_msg2: data length %i err1 %i err2 %i\n",
		   (__u64)data_end - (__u64)data, err1, err2);
		   len1, err1, err2);
	return SK_PASS;
}

SEC("sk_msg3")
int bpf_prog6(struct sk_msg_md *msg)
{
	void *data_end = (void *)(long) msg->data_end;
	void *data = (void *)(long) msg->data;
	int *bytes, zero = 0;
	int *bytes, zero = 0, one = 1;
	int *start, *end;

	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes)
@@ -179,15 +206,18 @@ int bpf_prog6(struct sk_msg_md *msg)
	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
	if (bytes)
		bpf_msg_cork_bytes(msg, *bytes);
	start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
	end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
	if (start && end)
		bpf_msg_pull_data(msg, *start, *end, 0);
	return bpf_msg_redirect_map(msg, &sock_map_redir, zero, 0);
}

SEC("sk_msg4")
int bpf_prog7(struct sk_msg_md *msg)
{
	void *data_end = (void *)(long) msg->data_end;
	void *data = (void *)(long) msg->data;
	int *bytes, err1 = 0, err2 = 0, zero = 0;
	int err1 = 0, err2 = 0, zero = 0, one = 1;
	int *bytes, *start, *end, len1, len2;

	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes)
@@ -195,9 +225,24 @@ int bpf_prog7(struct sk_msg_md *msg)
	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
	if (bytes)
		err2 = bpf_msg_cork_bytes(msg, *bytes);

	len1 = (__u64)msg->data_end - (__u64)msg->data;
	start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
	end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
	if (start && end) {
		int err;

		bpf_printk("sk_msg2: pull(%i:%i)\n",
			   start ? *start : 0, end ? *end : 0);
		err = bpf_msg_pull_data(msg, *start, *end, 0);
		if (err)
			bpf_printk("sk_msg2: pull_data err %i\n",
				   err);
		len2 = (__u64)msg->data_end - (__u64)msg->data;
		bpf_printk("sk_msg2: length update %i->%i\n",
			   len1, len2);
	}
	bpf_printk("sk_msg3: redirect(%iB) err1=%i err2=%i\n",
		   (__u64)data_end - (__u64)data, err1, err2);
		   len1, err1, err2);
	return bpf_msg_redirect_map(msg, &sock_map_redir, zero, 0);
}

@@ -239,7 +284,8 @@ int bpf_prog9(struct sk_msg_md *msg)
SEC("sk_msg7")
int bpf_prog10(struct sk_msg_md *msg)
{
	int *bytes, zero = 0;
	int *bytes, zero = 0, one = 1;
	int *start, *end;

	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes)
@@ -247,6 +293,11 @@ int bpf_prog10(struct sk_msg_md *msg)
	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
	if (bytes)
		bpf_msg_cork_bytes(msg, *bytes);
	start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
	end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
	if (start && end)
		bpf_msg_pull_data(msg, *start, *end, 0);

	return SK_DROP;
}

+32 −0
Original line number Diff line number Diff line
@@ -62,6 +62,8 @@ int txmsg_redir_noisy;
int txmsg_drop;
int txmsg_apply;
int txmsg_cork;
int txmsg_start;
int txmsg_end;

static const struct option long_options[] = {
	{"help",	no_argument,		NULL, 'h' },
@@ -79,6 +81,8 @@ static const struct option long_options[] = {
	{"txmsg_drop",		no_argument,	&txmsg_drop, 1 },
	{"txmsg_apply",	required_argument,	NULL, 'a'},
	{"txmsg_cork",	required_argument,	NULL, 'k'},
	{"txmsg_start", required_argument,	NULL, 's'},
	{"txmsg_end",	required_argument,	NULL, 'e'},
	{0, 0, NULL, 0 }
};

@@ -572,6 +576,12 @@ int main(int argc, char **argv)
	while ((opt = getopt_long(argc, argv, ":dhvc:r:i:l:t:",
				  long_options, &longindex)) != -1) {
		switch (opt) {
		case 's':
			txmsg_start = atoi(optarg);
			break;
		case 'e':
			txmsg_end = atoi(optarg);
			break;
		case 'a':
			txmsg_apply = atoi(optarg);
			break;
@@ -761,6 +771,28 @@ int main(int argc, char **argv)
			}
		}

		if (txmsg_start) {
			err = bpf_map_update_elem(map_fd[5],
						  &i, &txmsg_start, BPF_ANY);
			if (err) {
				fprintf(stderr,
					"ERROR: bpf_map_update_elem (txmsg_start):  %d (%s)\n",
					err, strerror(errno));
				return err;
			}
		}

		if (txmsg_end) {
			i = 1;
			err = bpf_map_update_elem(map_fd[5],
						  &i, &txmsg_end, BPF_ANY);
			if (err) {
				fprintf(stderr,
					"ERROR: bpf_map_update_elem (txmsg_end):  %d (%s)\n",
					err, strerror(errno));
				return err;
			}
		}
	}

	if (txmsg_drop)
+2 −1
Original line number Diff line number Diff line
@@ -793,7 +793,8 @@ union bpf_attr {
	FN(sock_ops_cb_flags_set),	\
	FN(msg_redirect_map),		\
	FN(msg_apply_bytes),		\
	FN(msg_cork_bytes),
	FN(msg_cork_bytes),		\
	FN(msg_pull_data),

/* integer value in 'imm' field of BPF_CALL instruction selects which helper
 * function eBPF program intends to call
+2 −0
Original line number Diff line number Diff line
@@ -92,6 +92,8 @@ static int (*bpf_msg_apply_bytes)(void *ctx, int len) =
	(void *) BPF_FUNC_msg_apply_bytes;
static int (*bpf_msg_cork_bytes)(void *ctx, int len) =
	(void *) BPF_FUNC_msg_cork_bytes;
static int (*bpf_msg_pull_data)(void *ctx, int start, int end, int flags) =
	(void *) BPF_FUNC_msg_pull_data;

/* llvm builtin functions that eBPF C program may use to
 * emit BPF_LD_ABS and BPF_LD_IND instructions