1 /* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
2 /*
3 * SunRPC GSS Kerberos 5 mechanism internal definitions
4 *
5 * Copyright (c) 2022 Oracle and/or its affiliates.
6 */
7
8 #ifndef _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H
9 #define _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H
10
11 /*
12 * The RFCs often specify payload lengths in bits. This helper
13 * converts a specified bit-length to the number of octets/bytes.
14 */
15 #define BITS2OCTETS(x) ((x) / 8)
16
17 struct krb5_ctx;
18
19 struct gss_krb5_enctype {
20 const u32 etype; /* encryption (key) type */
21 const u32 ctype; /* checksum type */
22 const char *name; /* "friendly" name */
23 const char *encrypt_name; /* crypto encrypt name */
24 const char *aux_cipher; /* aux encrypt cipher name */
25 const char *cksum_name; /* crypto checksum name */
26 const u16 signalg; /* signing algorithm */
27 const u16 sealalg; /* sealing algorithm */
28 const u32 cksumlength; /* checksum length */
29 const u32 keyed_cksum; /* is it a keyed cksum? */
30 const u32 keybytes; /* raw key len, in bytes */
31 const u32 keylength; /* protocol key length, in octets */
32 const u32 Kc_length; /* checksum subkey length, in octets */
33 const u32 Ke_length; /* encryption subkey length, in octets */
34 const u32 Ki_length; /* integrity subkey length, in octets */
35
36 int (*import_ctx)(struct krb5_ctx *ctx, gfp_t gfp_mask);
37 int (*derive_key)(const struct gss_krb5_enctype *gk5e,
38 const struct xdr_netobj *in,
39 struct xdr_netobj *out,
40 const struct xdr_netobj *label,
41 gfp_t gfp_mask);
42 u32 (*encrypt)(struct krb5_ctx *kctx, u32 offset,
43 struct xdr_buf *buf, struct page **pages);
44 u32 (*decrypt)(struct krb5_ctx *kctx, u32 offset, u32 len,
45 struct xdr_buf *buf, u32 *headskip, u32 *tailskip);
46 u32 (*get_mic)(struct krb5_ctx *kctx, struct xdr_buf *text,
47 struct xdr_netobj *token);
48 u32 (*verify_mic)(struct krb5_ctx *kctx, struct xdr_buf *message_buffer,
49 struct xdr_netobj *read_token);
50 u32 (*wrap)(struct krb5_ctx *kctx, int offset,
51 struct xdr_buf *buf, struct page **pages);
52 u32 (*unwrap)(struct krb5_ctx *kctx, int offset, int len,
53 struct xdr_buf *buf, unsigned int *slack,
54 unsigned int *align);
55 };
56
57 /* krb5_ctx flags definitions */
58 #define KRB5_CTX_FLAG_INITIATOR 0x00000001
59 #define KRB5_CTX_FLAG_ACCEPTOR_SUBKEY 0x00000004
60
61 struct krb5_ctx {
62 int initiate; /* 1 = initiating, 0 = accepting */
63 u32 enctype;
64 u32 flags;
65 const struct gss_krb5_enctype *gk5e; /* enctype-specific info */
66 struct crypto_sync_skcipher *enc;
67 struct crypto_sync_skcipher *seq;
68 struct crypto_sync_skcipher *acceptor_enc;
69 struct crypto_sync_skcipher *initiator_enc;
70 struct crypto_sync_skcipher *acceptor_enc_aux;
71 struct crypto_sync_skcipher *initiator_enc_aux;
72 struct crypto_ahash *acceptor_sign;
73 struct crypto_ahash *initiator_sign;
74 struct crypto_ahash *initiator_integ;
75 struct crypto_ahash *acceptor_integ;
76 u8 Ksess[GSS_KRB5_MAX_KEYLEN]; /* session key */
77 u8 cksum[GSS_KRB5_MAX_KEYLEN];
78 atomic_t seq_send;
79 atomic64_t seq_send64;
80 time64_t endtime;
81 struct xdr_netobj mech_used;
82 };
83
84 /*
85 * GSS Kerberos 5 mechanism Per-Message calls.
86 */
87
88 u32 gss_krb5_get_mic_v1(struct krb5_ctx *ctx, struct xdr_buf *text,
89 struct xdr_netobj *token);
90 u32 gss_krb5_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text,
91 struct xdr_netobj *token);
92
93 u32 gss_krb5_verify_mic_v1(struct krb5_ctx *ctx, struct xdr_buf *message_buffer,
94 struct xdr_netobj *read_token);
95 u32 gss_krb5_verify_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *message_buffer,
96 struct xdr_netobj *read_token);
97
98 u32 gss_krb5_wrap_v1(struct krb5_ctx *kctx, int offset,
99 struct xdr_buf *buf, struct page **pages);
100 u32 gss_krb5_wrap_v2(struct krb5_ctx *kctx, int offset,
101 struct xdr_buf *buf, struct page **pages);
102
103 u32 gss_krb5_unwrap_v1(struct krb5_ctx *kctx, int offset, int len,
104 struct xdr_buf *buf, unsigned int *slack,
105 unsigned int *align);
106 u32 gss_krb5_unwrap_v2(struct krb5_ctx *kctx, int offset, int len,
107 struct xdr_buf *buf, unsigned int *slack,
108 unsigned int *align);
109
110 /*
111 * Implementation internal functions
112 */
113
114 /* Key Derivation Functions */
115
116 int krb5_derive_key_v1(const struct gss_krb5_enctype *gk5e,
117 const struct xdr_netobj *inkey,
118 struct xdr_netobj *outkey,
119 const struct xdr_netobj *label,
120 gfp_t gfp_mask);
121
122 int krb5_derive_key_v2(const struct gss_krb5_enctype *gk5e,
123 const struct xdr_netobj *inkey,
124 struct xdr_netobj *outkey,
125 const struct xdr_netobj *label,
126 gfp_t gfp_mask);
127
128 int krb5_kdf_hmac_sha2(const struct gss_krb5_enctype *gk5e,
129 const struct xdr_netobj *inkey,
130 struct xdr_netobj *outkey,
131 const struct xdr_netobj *in_constant,
132 gfp_t gfp_mask);
133
134 int krb5_kdf_feedback_cmac(const struct gss_krb5_enctype *gk5e,
135 const struct xdr_netobj *inkey,
136 struct xdr_netobj *outkey,
137 const struct xdr_netobj *in_constant,
138 gfp_t gfp_mask);
139
140 /**
141 * krb5_derive_key - Derive a subkey from a protocol key
142 * @kctx: Kerberos 5 context
143 * @inkey: base protocol key
144 * @outkey: OUT: derived key
145 * @usage: key usage value
146 * @seed: key usage seed (one octet)
147 * @gfp_mask: memory allocation control flags
148 *
149 * Caller sets @outkey->len to the desired length of the derived key.
150 *
151 * On success, returns 0 and fills in @outkey. A negative errno value
152 * is returned on failure.
153 */
krb5_derive_key(struct krb5_ctx * kctx,const struct xdr_netobj * inkey,struct xdr_netobj * outkey,u32 usage,u8 seed,gfp_t gfp_mask)154 static inline int krb5_derive_key(struct krb5_ctx *kctx,
155 const struct xdr_netobj *inkey,
156 struct xdr_netobj *outkey,
157 u32 usage, u8 seed, gfp_t gfp_mask)
158 {
159 const struct gss_krb5_enctype *gk5e = kctx->gk5e;
160 u8 label_data[GSS_KRB5_K5CLENGTH];
161 struct xdr_netobj label = {
162 .len = sizeof(label_data),
163 .data = label_data,
164 };
165 __be32 *p = (__be32 *)label_data;
166
167 *p = cpu_to_be32(usage);
168 label_data[4] = seed;
169 return gk5e->derive_key(gk5e, inkey, outkey, &label, gfp_mask);
170 }
171
172 s32 krb5_make_seq_num(struct krb5_ctx *kctx, struct crypto_sync_skcipher *key,
173 int direction, u32 seqnum, unsigned char *cksum,
174 unsigned char *buf);
175
176 s32 krb5_get_seq_num(struct krb5_ctx *kctx, unsigned char *cksum,
177 unsigned char *buf, int *direction, u32 *seqnum);
178
179 void krb5_make_confounder(u8 *p, int conflen);
180
181 u32 make_checksum(struct krb5_ctx *kctx, char *header, int hdrlen,
182 struct xdr_buf *body, int body_offset, u8 *cksumkey,
183 unsigned int usage, struct xdr_netobj *cksumout);
184
185 u32 gss_krb5_checksum(struct crypto_ahash *tfm, char *header, int hdrlen,
186 const struct xdr_buf *body, int body_offset,
187 struct xdr_netobj *cksumout);
188
189 u32 krb5_encrypt(struct crypto_sync_skcipher *key, void *iv, void *in,
190 void *out, int length);
191
192 u32 krb5_decrypt(struct crypto_sync_skcipher *key, void *iv, void *in,
193 void *out, int length);
194
195 int xdr_extend_head(struct xdr_buf *buf, unsigned int base,
196 unsigned int shiftlen);
197
198 int gss_encrypt_xdr_buf(struct crypto_sync_skcipher *tfm,
199 struct xdr_buf *outbuf, int offset,
200 struct page **pages);
201
202 int gss_decrypt_xdr_buf(struct crypto_sync_skcipher *tfm,
203 struct xdr_buf *inbuf, int offset);
204
205 u32 gss_krb5_aes_encrypt(struct krb5_ctx *kctx, u32 offset,
206 struct xdr_buf *buf, struct page **pages);
207
208 u32 gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
209 struct xdr_buf *buf, u32 *plainoffset, u32 *plainlen);
210
211 u32 krb5_etm_encrypt(struct krb5_ctx *kctx, u32 offset, struct xdr_buf *buf,
212 struct page **pages);
213
214 u32 krb5_etm_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
215 struct xdr_buf *buf, u32 *headskip, u32 *tailskip);
216
217 #if IS_ENABLED(CONFIG_KUNIT)
218 void krb5_nfold(u32 inbits, const u8 *in, u32 outbits, u8 *out);
219 const struct gss_krb5_enctype *gss_krb5_lookup_enctype(u32 etype);
220 int krb5_cbc_cts_encrypt(struct crypto_sync_skcipher *cts_tfm,
221 struct crypto_sync_skcipher *cbc_tfm, u32 offset,
222 struct xdr_buf *buf, struct page **pages,
223 u8 *iv, unsigned int ivsize);
224 int krb5_cbc_cts_decrypt(struct crypto_sync_skcipher *cts_tfm,
225 struct crypto_sync_skcipher *cbc_tfm,
226 u32 offset, struct xdr_buf *buf);
227 u32 krb5_etm_checksum(struct crypto_sync_skcipher *cipher,
228 struct crypto_ahash *tfm, const struct xdr_buf *body,
229 int body_offset, struct xdr_netobj *cksumout);
230 #endif
231
232 #endif /* _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H */
233