samples/sockmap/sockmap_kern.c - linux - Git at Google

 /* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  * General Public License for more details.
  */
 #include <uapi/linux/bpf.h>
 #include <uapi/linux/if_ether.h>
 #include <uapi/linux/if_packet.h>
 #include <uapi/linux/ip.h>
 #include "../../tools/testing/selftests/bpf/bpf_helpers.h"
 #include "../../tools/testing/selftests/bpf/bpf_endian.h"

 /* Sockmap sample program connects a client and a backend together
  * using cgroups.
  *
  *    client:X <---> frontend:80 client:X <---> backend:80
  *
  * For simplicity we hard code values here and bind 1:1. The hard
  * coded values are part of the setup in sockmap.sh script that
  * is associated with this BPF program.
  *
  * The bpf_printk is verbose and prints information as connections
  * are established and verdicts are decided.
  */

 #define bpf_printk(fmt, ...)					\
 ({								\
 	       char ____fmt[] = fmt;				\
 	       bpf_trace_printk(____fmt, sizeof(____fmt),	\
 				##__VA_ARGS__);			\
 })

 struct bpf_map_def SEC("maps") sock_map = {
 	.type = BPF_MAP_TYPE_SOCKMAP,
 	.key_size = sizeof(int),
 	.value_size = sizeof(int),
 	.max_entries = 20,
 };

 struct bpf_map_def SEC("maps") sock_map_txmsg = {
 	.type = BPF_MAP_TYPE_SOCKMAP,
 	.key_size = sizeof(int),
 	.value_size = sizeof(int),
 	.max_entries = 20,
 };

 struct bpf_map_def SEC("maps") sock_map_redir = {
 	.type = BPF_MAP_TYPE_SOCKMAP,
 	.key_size = sizeof(int),
 	.value_size = sizeof(int),
 	.max_entries = 20,
 };

 struct bpf_map_def SEC("maps") sock_apply_bytes = {
 	.type = BPF_MAP_TYPE_ARRAY,
 	.key_size = sizeof(int),
 	.value_size = sizeof(int),
 	.max_entries = 1
 };

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

 struct bpf_map_def SEC("maps") sock_redir_flags = {
 	.type = BPF_MAP_TYPE_ARRAY,
 	.key_size = sizeof(int),
 	.value_size = sizeof(int),
 	.max_entries = 1
 };

 struct bpf_map_def SEC("maps") sock_skb_opts = {
 	.type = BPF_MAP_TYPE_ARRAY,
 	.key_size = sizeof(int),
 	.value_size = sizeof(int),
 	.max_entries = 1
 };

 SEC("sk_skb1")
 int bpf_prog1(struct __sk_buff *skb)
 {
 	return skb->len;
 }

 SEC("sk_skb2")
 int bpf_prog2(struct __sk_buff *skb)
 {
 	__u32 lport = skb->local_port;
 	__u32 rport = skb->remote_port;
 	int len, *f, ret, zero = 0;
 	__u64 flags = 0;

 	if (lport == 10000)
 		ret = 10;
 	else
 		ret = 1;

 	len = (__u32)skb->data_end - (__u32)skb->data;
 	f = bpf_map_lookup_elem(&sock_skb_opts, &zero);
 	if (f && *f) {
 		ret = 3;
 		flags = *f;
 	}

 	bpf_printk("sk_skb2: redirect(%iB) flags=%i\n",
 		   len, flags);
 	return bpf_sk_redirect_map(skb, &sock_map, ret, flags);
 }

 SEC("sockops")
 int bpf_sockmap(struct bpf_sock_ops *skops)
 {
 	__u32 lport, rport;
 	int op, err = 0, index, key, ret;


 	op = (int) skops->op;

 	switch (op) {
 	case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
 		lport = skops->local_port;
 		rport = skops->remote_port;

 		if (lport == 10000) {
 			ret = 1;
 			err = bpf_sock_map_update(skops, &sock_map, &ret,
 						  BPF_NOEXIST);
 			bpf_printk("passive(%i -> %i) map ctx update err: %d\n",
 				   lport, bpf_ntohl(rport), err);
 		}
 		break;
 	case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
 		lport = skops->local_port;
 		rport = skops->remote_port;

 		if (bpf_ntohl(rport) == 10001) {
 			ret = 10;
 			err = bpf_sock_map_update(skops, &sock_map, &ret,
 						  BPF_NOEXIST);
 			bpf_printk("active(%i -> %i) map ctx update err: %d\n",
 				   lport, bpf_ntohl(rport), err);
 		}
 		break;
 	default:
 		break;
 	}

 	return 0;
 }

 SEC("sk_msg1")
 int bpf_prog4(struct sk_msg_md *msg)
 {
 	int *bytes, zero = 0, one = 1;
 	int *start, *end;

 	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
 	if (bytes)
 		bpf_msg_apply_bytes(msg, *bytes);
 	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)
 {
 	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)
 		err1 = bpf_msg_apply_bytes(msg, *bytes);
 	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",
 		   len1, err1, err2);
 	return SK_PASS;
 }

 SEC("sk_msg3")
 int bpf_prog6(struct sk_msg_md *msg)
 {
 	int *bytes, zero = 0, one = 1, key = 0;
 	int *start, *end, *f;
 	__u64 flags = 0;

 	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
 	if (bytes)
 		bpf_msg_apply_bytes(msg, *bytes);
 	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);
 	f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
 	if (f && *f) {
 		key = 2;
 		flags = *f;
 	}
 	return bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
 }

 SEC("sk_msg4")
 int bpf_prog7(struct sk_msg_md *msg)
 {
 	int err1 = 0, err2 = 0, zero = 0, one = 1, key = 0;
 	int *f, *bytes, *start, *end, len1, len2;
 	__u64 flags = 0;

 		int err;
 	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
 	if (bytes)
 		err1 = bpf_msg_apply_bytes(msg, *bytes);
 	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) {

 		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);
 	}
 	f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
 	if (f && *f) {
 		key = 2;
 		flags = *f;
 	}
 	bpf_printk("sk_msg3: redirect(%iB) flags=%i err=%i\n",
 		   len1, flags, err1 ? err1 : err2);
 	err = bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
 	bpf_printk("sk_msg3: err %i\n", err);
 	return err;
 }

 SEC("sk_msg5")
 int bpf_prog8(struct sk_msg_md *msg)
 {
 	void *data_end = (void *)(long) msg->data_end;
 	void *data = (void *)(long) msg->data;
 	int ret = 0, *bytes, zero = 0;

 	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
 	if (bytes) {
 		ret = bpf_msg_apply_bytes(msg, *bytes);
 		if (ret)
 			return SK_DROP;
 	} else {
 		return SK_DROP;
 	}
 	return SK_PASS;
 }
 SEC("sk_msg6")
 int bpf_prog9(struct sk_msg_md *msg)
 {
 	void *data_end = (void *)(long) msg->data_end;
 	void *data = (void *)(long) msg->data;
 	int ret = 0, *bytes, zero = 0;

 	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
 	if (bytes) {
 		if (((__u64)data_end - (__u64)data) >= *bytes)
 			return SK_PASS;
 		ret = bpf_msg_cork_bytes(msg, *bytes);
 		if (ret)
 			return SK_DROP;
 	}
 	return SK_PASS;
 }

 SEC("sk_msg7")
 int bpf_prog10(struct sk_msg_md *msg)
 {
 	int *bytes, zero = 0, one = 1;
 	int *start, *end;

 	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
 	if (bytes)
 		bpf_msg_apply_bytes(msg, *bytes);
 	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;
 }


 char _license[] SEC("license") = "GPL";
	/* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of version 2 of the GNU General Public
	* License as published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*/
	#include <uapi/linux/bpf.h>
	#include <uapi/linux/if_ether.h>
	#include <uapi/linux/if_packet.h>
	#include <uapi/linux/ip.h>
	#include "../../tools/testing/selftests/bpf/bpf_helpers.h"
	#include "../../tools/testing/selftests/bpf/bpf_endian.h"

	/* Sockmap sample program connects a client and a backend together
	* using cgroups.
	*
	* client:X <---> frontend:80 client:X <---> backend:80
	*
	* For simplicity we hard code values here and bind 1:1. The hard
	* coded values are part of the setup in sockmap.sh script that
	* is associated with this BPF program.
	*
	* The bpf_printk is verbose and prints information as connections
	* are established and verdicts are decided.
	*/

	#define bpf_printk(fmt, ...) \
	({ \
	char ____fmt[] = fmt; \
	bpf_trace_printk(____fmt, sizeof(____fmt), \
	##__VA_ARGS__); \
	})

	struct bpf_map_def SEC("maps") sock_map = {
	.type = BPF_MAP_TYPE_SOCKMAP,
	.key_size = sizeof(int),
	.value_size = sizeof(int),
	.max_entries = 20,
	};

	struct bpf_map_def SEC("maps") sock_map_txmsg = {
	.type = BPF_MAP_TYPE_SOCKMAP,
	.key_size = sizeof(int),
	.value_size = sizeof(int),
	.max_entries = 20,
	};

	struct bpf_map_def SEC("maps") sock_map_redir = {
	.type = BPF_MAP_TYPE_SOCKMAP,
	.key_size = sizeof(int),
	.value_size = sizeof(int),
	.max_entries = 20,
	};

	struct bpf_map_def SEC("maps") sock_apply_bytes = {
	.type = BPF_MAP_TYPE_ARRAY,
	.key_size = sizeof(int),
	.value_size = sizeof(int),
	.max_entries = 1
	};

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

	struct bpf_map_def SEC("maps") sock_redir_flags = {
	.type = BPF_MAP_TYPE_ARRAY,
	.key_size = sizeof(int),
	.value_size = sizeof(int),
	.max_entries = 1
	};

	struct bpf_map_def SEC("maps") sock_skb_opts = {
	.type = BPF_MAP_TYPE_ARRAY,
	.key_size = sizeof(int),
	.value_size = sizeof(int),
	.max_entries = 1
	};

	SEC("sk_skb1")
	int bpf_prog1(struct __sk_buff *skb)
	{
	return skb->len;
	}

	SEC("sk_skb2")
	int bpf_prog2(struct __sk_buff *skb)
	{
	__u32 lport = skb->local_port;
	__u32 rport = skb->remote_port;
	int len, *f, ret, zero = 0;
	__u64 flags = 0;

	if (lport == 10000)
	ret = 10;
	else
	ret = 1;

	len = (__u32)skb->data_end - (__u32)skb->data;
	f = bpf_map_lookup_elem(&sock_skb_opts, &zero);
	if (f && *f) {
	ret = 3;
	flags = *f;
	}

	bpf_printk("sk_skb2: redirect(%iB) flags=%i\n",
	len, flags);
	return bpf_sk_redirect_map(skb, &sock_map, ret, flags);
	}

	SEC("sockops")
	int bpf_sockmap(struct bpf_sock_ops *skops)
	{
	__u32 lport, rport;
	int op, err = 0, index, key, ret;


	op = (int) skops->op;

	switch (op) {
	case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
	lport = skops->local_port;
	rport = skops->remote_port;

	if (lport == 10000) {
	ret = 1;
	err = bpf_sock_map_update(skops, &sock_map, &ret,
	BPF_NOEXIST);
	bpf_printk("passive(%i -> %i) map ctx update err: %d\n",
	lport, bpf_ntohl(rport), err);
	}
	break;
	case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
	lport = skops->local_port;
	rport = skops->remote_port;

	if (bpf_ntohl(rport) == 10001) {
	ret = 10;
	err = bpf_sock_map_update(skops, &sock_map, &ret,
	BPF_NOEXIST);
	bpf_printk("active(%i -> %i) map ctx update err: %d\n",
	lport, bpf_ntohl(rport), err);
	}
	break;
	default:
	break;
	}

	return 0;
	}

	SEC("sk_msg1")
	int bpf_prog4(struct sk_msg_md *msg)
	{
	int *bytes, zero = 0, one = 1;
	int start, end;

	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes)
	bpf_msg_apply_bytes(msg, *bytes);
	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)
	{
	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)
	err1 = bpf_msg_apply_bytes(msg, *bytes);
	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",
	len1, err1, err2);
	return SK_PASS;
	}

	SEC("sk_msg3")
	int bpf_prog6(struct sk_msg_md *msg)
	{
	int *bytes, zero = 0, one = 1, key = 0;
	int start, end, *f;
	__u64 flags = 0;

	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes)
	bpf_msg_apply_bytes(msg, *bytes);
	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);
	f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
	if (f && *f) {
	key = 2;
	flags = *f;
	}
	return bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
	}

	SEC("sk_msg4")
	int bpf_prog7(struct sk_msg_md *msg)
	{
	int err1 = 0, err2 = 0, zero = 0, one = 1, key = 0;
	int f, bytes, start, end, len1, len2;
	__u64 flags = 0;

	int err;
	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes)
	err1 = bpf_msg_apply_bytes(msg, *bytes);
	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) {

	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);
	}
	f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
	if (f && *f) {
	key = 2;
	flags = *f;
	}
	bpf_printk("sk_msg3: redirect(%iB) flags=%i err=%i\n",
	len1, flags, err1 ? err1 : err2);
	err = bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
	bpf_printk("sk_msg3: err %i\n", err);
	return err;
	}

	SEC("sk_msg5")
	int bpf_prog8(struct sk_msg_md *msg)
	{
	void data_end = (void )(long) msg->data_end;
	void data = (void )(long) msg->data;
	int ret = 0, *bytes, zero = 0;

	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes) {
	ret = bpf_msg_apply_bytes(msg, *bytes);
	if (ret)
	return SK_DROP;
	} else {
	return SK_DROP;
	}
	return SK_PASS;
	}
	SEC("sk_msg6")
	int bpf_prog9(struct sk_msg_md *msg)
	{
	void data_end = (void )(long) msg->data_end;
	void data = (void )(long) msg->data;
	int ret = 0, *bytes, zero = 0;

	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
	if (bytes) {
	if (((__u64)data_end - (__u64)data) >= *bytes)
	return SK_PASS;
	ret = bpf_msg_cork_bytes(msg, *bytes);
	if (ret)
	return SK_DROP;
	}
	return SK_PASS;
	}

	SEC("sk_msg7")
	int bpf_prog10(struct sk_msg_md *msg)
	{
	int *bytes, zero = 0, one = 1;
	int start, end;

	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
	if (bytes)
	bpf_msg_apply_bytes(msg, *bytes);
	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;
	}


	char _license[] SEC("license") = "GPL";