1 /* SPDX-License-Identifier: GPL-2.0 */ 1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __NET_GUE_H 2 #ifndef __NET_GUE_H
3 #define __NET_GUE_H 3 #define __NET_GUE_H
4 4
5 /* Definitions for the GUE header, standard an 5 /* Definitions for the GUE header, standard and private flags, lengths
6 * of optional fields are below. 6 * of optional fields are below.
7 * 7 *
8 * Diagram of GUE header: 8 * Diagram of GUE header:
9 * 9 *
10 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 10 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
11 * |Ver|C| Hlen | Proto/ctype | St 11 * |Ver|C| Hlen | Proto/ctype | Standard flags |P|
12 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 12 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
13 * | 13 * | |
14 * ~ Fields (optional) 14 * ~ Fields (optional) ~
15 * | 15 * | |
16 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 16 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
17 * | Private flags (optional, P bit 17 * | Private flags (optional, P bit is set) |
18 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 18 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
19 * | 19 * | |
20 * ~ Private fields (optiona 20 * ~ Private fields (optional) ~
21 * | 21 * | |
22 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 22 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
23 * 23 *
24 * C bit indicates control message when set, d 24 * C bit indicates control message when set, data message when unset.
25 * For a control message, proto/ctype is inter 25 * For a control message, proto/ctype is interpreted as a type of
26 * control message. For data messages, proto/c 26 * control message. For data messages, proto/ctype is the IP protocol
27 * of the next header. 27 * of the next header.
28 * 28 *
29 * P bit indicates private flags field is pres 29 * P bit indicates private flags field is present. The private flags
30 * may refer to options placed after this fiel 30 * may refer to options placed after this field.
31 */ 31 */
32 32
33 #include <asm/byteorder.h> <<
34 #include <linux/types.h> <<
35 <<
36 struct guehdr { 33 struct guehdr {
37 union { 34 union {
38 struct { 35 struct {
39 #if defined(__LITTLE_ENDIAN_BITFIELD) 36 #if defined(__LITTLE_ENDIAN_BITFIELD)
40 __u8 hlen:5, 37 __u8 hlen:5,
41 control:1, 38 control:1,
42 version:2; 39 version:2;
43 #elif defined (__BIG_ENDIAN_BITFIELD) 40 #elif defined (__BIG_ENDIAN_BITFIELD)
44 __u8 version:2, 41 __u8 version:2,
45 control:1, 42 control:1,
46 hlen:5; 43 hlen:5;
47 #else 44 #else
48 #error "Please fix <asm/byteorder.h>" 45 #error "Please fix <asm/byteorder.h>"
49 #endif 46 #endif
50 __u8 proto_ctype; 47 __u8 proto_ctype;
51 __be16 flags; 48 __be16 flags;
52 }; 49 };
53 __be32 word; 50 __be32 word;
54 }; 51 };
55 }; 52 };
56 53
57 /* Standard flags in GUE header */ 54 /* Standard flags in GUE header */
58 55
59 #define GUE_FLAG_PRIV htons(1<<0) /* Pri 56 #define GUE_FLAG_PRIV htons(1<<0) /* Private flags are in options */
60 #define GUE_LEN_PRIV 4 57 #define GUE_LEN_PRIV 4
61 58
62 #define GUE_FLAGS_ALL (GUE_FLAG_PRIV) 59 #define GUE_FLAGS_ALL (GUE_FLAG_PRIV)
63 60
64 /* Private flags in the private option extensi 61 /* Private flags in the private option extension */
65 62
66 #define GUE_PFLAG_REMCSUM htonl(1U << 31 63 #define GUE_PFLAG_REMCSUM htonl(1U << 31)
67 #define GUE_PLEN_REMCSUM 4 64 #define GUE_PLEN_REMCSUM 4
68 65
69 #define GUE_PFLAGS_ALL (GUE_PFLAG_REMCSUM) 66 #define GUE_PFLAGS_ALL (GUE_PFLAG_REMCSUM)
70 67
71 /* Functions to compute options length corresp 68 /* Functions to compute options length corresponding to flags.
72 * If we ever have a lot of flags this can be 69 * If we ever have a lot of flags this can be potentially be
73 * converted to a more optimized algorithm (ta 70 * converted to a more optimized algorithm (table lookup
74 * for instance). 71 * for instance).
75 */ 72 */
76 static inline size_t guehdr_flags_len(__be16 f 73 static inline size_t guehdr_flags_len(__be16 flags)
77 { 74 {
78 return ((flags & GUE_FLAG_PRIV) ? GUE_ 75 return ((flags & GUE_FLAG_PRIV) ? GUE_LEN_PRIV : 0);
79 } 76 }
80 77
81 static inline size_t guehdr_priv_flags_len(__b 78 static inline size_t guehdr_priv_flags_len(__be32 flags)
82 { 79 {
83 return 0; 80 return 0;
84 } 81 }
85 82
86 /* Validate standard and private flags. Return 83 /* Validate standard and private flags. Returns non-zero (meaning invalid)
87 * if there is an unknown standard or private 84 * if there is an unknown standard or private flags, or the options length for
88 * the flags exceeds the options length specif 85 * the flags exceeds the options length specific in hlen of the GUE header.
89 */ 86 */
90 static inline int validate_gue_flags(struct gu 87 static inline int validate_gue_flags(struct guehdr *guehdr, size_t optlen)
91 { 88 {
92 __be16 flags = guehdr->flags; 89 __be16 flags = guehdr->flags;
93 size_t len; 90 size_t len;
94 91
95 if (flags & ~GUE_FLAGS_ALL) 92 if (flags & ~GUE_FLAGS_ALL)
96 return 1; 93 return 1;
97 94
98 len = guehdr_flags_len(flags); 95 len = guehdr_flags_len(flags);
99 if (len > optlen) 96 if (len > optlen)
100 return 1; 97 return 1;
101 98
102 if (flags & GUE_FLAG_PRIV) { 99 if (flags & GUE_FLAG_PRIV) {
103 /* Private flags are last four 100 /* Private flags are last four bytes accounted in
104 * guehdr_flags_len 101 * guehdr_flags_len
105 */ 102 */
106 __be32 pflags = *(__be32 *)((v 103 __be32 pflags = *(__be32 *)((void *)&guehdr[1] +
107 le 104 len - GUE_LEN_PRIV);
108 105
109 if (pflags & ~GUE_PFLAGS_ALL) 106 if (pflags & ~GUE_PFLAGS_ALL)
110 return 1; 107 return 1;
111 108
112 len += guehdr_priv_flags_len(p 109 len += guehdr_priv_flags_len(pflags);
113 if (len > optlen) 110 if (len > optlen)
114 return 1; 111 return 1;
115 } 112 }
116 113
117 return 0; 114 return 0;
118 } 115 }
119 116
120 #endif 117 #endif
121 118
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.