1/* SPDX-License-Identifier: GPL-2.0 */
  2/* Copyright (c) 2020 Facebook */
  3
  4#ifndef _TEST_TCP_HDR_OPTIONS_H
  5#define _TEST_TCP_HDR_OPTIONS_H
  6
  7struct bpf_test_option {
  8	__u8 flags;
  9	__u8 max_delack_ms;
 10	__u8 rand;
 11} __attribute__((packed));
 12
 13enum {
 14	OPTION_RESEND,
 15	OPTION_MAX_DELACK_MS,
 16	OPTION_RAND,
 17	__NR_OPTION_FLAGS,
 18};
 19
 20#define OPTION_F_RESEND		(1 << OPTION_RESEND)
 21#define OPTION_F_MAX_DELACK_MS	(1 << OPTION_MAX_DELACK_MS)
 22#define OPTION_F_RAND		(1 << OPTION_RAND)
 23#define OPTION_MASK		((1 << __NR_OPTION_FLAGS) - 1)
 24
 25#define TEST_OPTION_FLAGS(flags, option) (1 & ((flags) >> (option)))
 26#define SET_OPTION_FLAGS(flags, option)	((flags) |= (1 << (option)))
 27
 28/* Store in bpf_sk_storage */
 29struct hdr_stg {
 30	bool active;
 31	bool resend_syn; /* active side only */
 32	bool syncookie;  /* passive side only */
 33	bool fastopen;	/* passive side only */
 34};
 35
 36struct linum_err {
 37	unsigned int linum;
 38	int err;
 39};
 40
 41#define TCPHDR_FIN 0x01
 42#define TCPHDR_SYN 0x02
 43#define TCPHDR_RST 0x04
 44#define TCPHDR_PSH 0x08
 45#define TCPHDR_ACK 0x10
 46#define TCPHDR_URG 0x20
 47#define TCPHDR_ECE 0x40
 48#define TCPHDR_CWR 0x80
 49#define TCPHDR_SYNACK (TCPHDR_SYN | TCPHDR_ACK)
 50
 51#define TCPOPT_EOL		0
 52#define TCPOPT_NOP		1
 53#define TCPOPT_MSS		2
 54#define TCPOPT_WINDOW		3
 55#define TCPOPT_EXP		254
 56
 57#define TCP_BPF_EXPOPT_BASE_LEN 4
 58#define MAX_TCP_HDR_LEN		60
 59#define MAX_TCP_OPTION_SPACE	40
 60
 61#ifdef BPF_PROG_TEST_TCP_HDR_OPTIONS
 62
 63#define CG_OK	1
 64#define CG_ERR	0
 65
 66#ifndef SOL_TCP
 67#define SOL_TCP 6
 68#endif
 69
 70struct tcp_exprm_opt {
 71	__u8 kind;
 72	__u8 len;
 73	__u16 magic;
 74	union {
 75		__u8 data[4];
 76		__u32 data32;
 77	};
 78} __attribute__((packed));
 79
 80struct tcp_opt {
 81	__u8 kind;
 82	__u8 len;
 83	union {
 84		__u8 data[4];
 85		__u32 data32;
 86	};
 87} __attribute__((packed));
 88
 89struct {
 90	__uint(type, BPF_MAP_TYPE_HASH);
 91	__uint(max_entries, 2);
 92	__type(key, int);
 93	__type(value, struct linum_err);
 94} lport_linum_map SEC(".maps");
 95
 96static inline unsigned int tcp_hdrlen(const struct tcphdr *th)
 97{
 98	return th->doff << 2;
 99}
100
101static inline __u8 skops_tcp_flags(const struct bpf_sock_ops *skops)
102{
103	return skops->skb_tcp_flags;
104}
105
106static inline void clear_hdr_cb_flags(struct bpf_sock_ops *skops)
107{
108	bpf_sock_ops_cb_flags_set(skops,
109				  skops->bpf_sock_ops_cb_flags &
110				  ~(BPF_SOCK_OPS_PARSE_UNKNOWN_HDR_OPT_CB_FLAG |
111				    BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG));
112}
113
114static inline void set_hdr_cb_flags(struct bpf_sock_ops *skops, __u32 extra)
115{
116	bpf_sock_ops_cb_flags_set(skops,
117				  skops->bpf_sock_ops_cb_flags |
118				  BPF_SOCK_OPS_PARSE_UNKNOWN_HDR_OPT_CB_FLAG |
119				  BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG |
120				  extra);
121}
122static inline void
123clear_parse_all_hdr_cb_flags(struct bpf_sock_ops *skops)
124{
125	bpf_sock_ops_cb_flags_set(skops,
126				  skops->bpf_sock_ops_cb_flags &
127				  ~BPF_SOCK_OPS_PARSE_ALL_HDR_OPT_CB_FLAG);
128}
129
130static inline void
131set_parse_all_hdr_cb_flags(struct bpf_sock_ops *skops)
132{
133	bpf_sock_ops_cb_flags_set(skops,
134				  skops->bpf_sock_ops_cb_flags |
135				  BPF_SOCK_OPS_PARSE_ALL_HDR_OPT_CB_FLAG);
136}
137
138#define RET_CG_ERR(__err) ({			\
139	struct linum_err __linum_err;		\
140	int __lport;				\
141						\
142	__linum_err.linum = __LINE__;		\
143	__linum_err.err = __err;		\
144	__lport = skops->local_port;		\
145	bpf_map_update_elem(&lport_linum_map, &__lport, &__linum_err, BPF_NOEXIST); \
146	clear_hdr_cb_flags(skops);					\
147	clear_parse_all_hdr_cb_flags(skops);				\
148	return CG_ERR;							\
149})
150
151#endif /* BPF_PROG_TEST_TCP_HDR_OPTIONS */
152
153#endif /* _TEST_TCP_HDR_OPTIONS_H */