net/sunrpc/auth_gss/gss_krb5_internal.h

   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 (*derive_key)(const struct gss_krb5_enctype *gk5e,
  37                           const struct xdr_netobj *in,
  38                           struct xdr_netobj *out,
  39                           const struct xdr_netobj *label,
  40                           gfp_t gfp_mask);
  41         u32 (*encrypt)(struct krb5_ctx *kctx, u32 offset,
  42                        struct xdr_buf *buf, struct page **pages);
  43         u32 (*decrypt)(struct krb5_ctx *kctx, u32 offset, u32 len,
  44                        struct xdr_buf *buf, u32 *headskip, u32 *tailskip);
  45         u32 (*get_mic)(struct krb5_ctx *kctx, struct xdr_buf *text,
  46                        struct xdr_netobj *token);
  47         u32 (*verify_mic)(struct krb5_ctx *kctx, struct xdr_buf *message_buffer,
  48                           struct xdr_netobj *read_token);
  49         u32 (*wrap)(struct krb5_ctx *kctx, int offset,
  50                     struct xdr_buf *buf, struct page **pages);
  51         u32 (*unwrap)(struct krb5_ctx *kctx, int offset, int len,
  52                       struct xdr_buf *buf, unsigned int *slack,
  53                       unsigned int *align);
  54 };
  55
  56 /* krb5_ctx flags definitions */
  57 #define KRB5_CTX_FLAG_INITIATOR         0x00000001
  58 #define KRB5_CTX_FLAG_ACCEPTOR_SUBKEY   0x00000004
  59
  60 struct krb5_ctx {
  61         int                     initiate; /* 1 = initiating, 0 = accepting */
  62         u32                     enctype;
  63         u32                     flags;
  64         const struct gss_krb5_enctype *gk5e; /* enctype-specific info */
  65         struct crypto_sync_skcipher *enc;
  66         struct crypto_sync_skcipher *seq;
  67         struct crypto_sync_skcipher *acceptor_enc;
  68         struct crypto_sync_skcipher *initiator_enc;
  69         struct crypto_sync_skcipher *acceptor_enc_aux;
  70         struct crypto_sync_skcipher *initiator_enc_aux;
  71         struct crypto_ahash     *acceptor_sign;
  72         struct crypto_ahash     *initiator_sign;
  73         struct crypto_ahash     *initiator_integ;
  74         struct crypto_ahash     *acceptor_integ;
  75         u8                      Ksess[GSS_KRB5_MAX_KEYLEN]; /* session key */
  76         u8                      cksum[GSS_KRB5_MAX_KEYLEN];
  77         atomic_t                seq_send;
  78         atomic64_t              seq_send64;
  79         time64_t                endtime;
  80         struct xdr_netobj       mech_used;
  81 };
  82
  83 /*
  84  * GSS Kerberos 5 mechanism Per-Message calls.
  85  */
  86
  87 u32 gss_krb5_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text,
  88                         struct xdr_netobj *token);
  89
  90 u32 gss_krb5_verify_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *message_buffer,
  91                            struct xdr_netobj *read_token);
  92
  93 u32 gss_krb5_wrap_v2(struct krb5_ctx *kctx, int offset,
  94                      struct xdr_buf *buf, struct page **pages);
  95
  96 u32 gss_krb5_unwrap_v2(struct krb5_ctx *kctx, int offset, int len,
  97                        struct xdr_buf *buf, unsigned int *slack,
  98                        unsigned int *align);
  99
 100 /*
 101  * Implementation internal functions
 102  */
 103
 104 /* Key Derivation Functions */
 105
 106 int krb5_derive_key_v2(const struct gss_krb5_enctype *gk5e,
 107                        const struct xdr_netobj *inkey,
 108                        struct xdr_netobj *outkey,
 109                        const struct xdr_netobj *label,
 110                        gfp_t gfp_mask);
 111
 112 int krb5_kdf_hmac_sha2(const struct gss_krb5_enctype *gk5e,
 113                        const struct xdr_netobj *inkey,
 114                        struct xdr_netobj *outkey,
 115                        const struct xdr_netobj *in_constant,
 116                        gfp_t gfp_mask);
 117
 118 int krb5_kdf_feedback_cmac(const struct gss_krb5_enctype *gk5e,
 119                            const struct xdr_netobj *inkey,
 120                            struct xdr_netobj *outkey,
 121                            const struct xdr_netobj *in_constant,
 122                            gfp_t gfp_mask);
 123
 124 /**
 125  * krb5_derive_key - Derive a subkey from a protocol key
 126  * @kctx: Kerberos 5 context
 127  * @inkey: base protocol key
 128  * @outkey: OUT: derived key
 129  * @usage: key usage value
 130  * @seed: key usage seed (one octet)
 131  * @gfp_mask: memory allocation control flags
 132  *
 133  * Caller sets @outkey->len to the desired length of the derived key.
 134  *
 135  * On success, returns 0 and fills in @outkey. A negative errno value
 136  * is returned on failure.
 137  */
 138 static inline int krb5_derive_key(struct krb5_ctx *kctx,
 139                                   const struct xdr_netobj *inkey,
 140                                   struct xdr_netobj *outkey,
 141                                   u32 usage, u8 seed, gfp_t gfp_mask)
 142 {
 143         const struct gss_krb5_enctype *gk5e = kctx->gk5e;
 144         u8 label_data[GSS_KRB5_K5CLENGTH];
 145         struct xdr_netobj label = {
 146                 .len    = sizeof(label_data),
 147                 .data   = label_data,
 148         };
 149         __be32 *p = (__be32 *)label_data;
 150
 151         *p = cpu_to_be32(usage);
 152         label_data[4] = seed;
 153         return gk5e->derive_key(gk5e, inkey, outkey, &label, gfp_mask);
 154 }
 155
 156 void krb5_make_confounder(u8 *p, int conflen);
 157
 158 u32 make_checksum(struct krb5_ctx *kctx, char *header, int hdrlen,
 159                   struct xdr_buf *body, int body_offset, u8 *cksumkey,
 160                   unsigned int usage, struct xdr_netobj *cksumout);
 161
 162 u32 gss_krb5_checksum(struct crypto_ahash *tfm, char *header, int hdrlen,
 163                       const struct xdr_buf *body, int body_offset,
 164                       struct xdr_netobj *cksumout);
 165
 166 u32 krb5_encrypt(struct crypto_sync_skcipher *key, void *iv, void *in,
 167                  void *out, int length);
 168
 169 u32 krb5_decrypt(struct crypto_sync_skcipher *key, void *iv, void *in,
 170                  void *out, int length);
 171
 172 int xdr_extend_head(struct xdr_buf *buf, unsigned int base,
 173                     unsigned int shiftlen);
 174
 175 int gss_encrypt_xdr_buf(struct crypto_sync_skcipher *tfm,
 176                         struct xdr_buf *outbuf, int offset,
 177                         struct page **pages);
 178
 179 int gss_decrypt_xdr_buf(struct crypto_sync_skcipher *tfm,
 180                         struct xdr_buf *inbuf, int offset);
 181
 182 u32 gss_krb5_aes_encrypt(struct krb5_ctx *kctx, u32 offset,
 183                          struct xdr_buf *buf, struct page **pages);
 184
 185 u32 gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
 186                          struct xdr_buf *buf, u32 *plainoffset, u32 *plainlen);
 187
 188 u32 krb5_etm_encrypt(struct krb5_ctx *kctx, u32 offset, struct xdr_buf *buf,
 189                      struct page **pages);
 190
 191 u32 krb5_etm_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
 192                      struct xdr_buf *buf, u32 *headskip, u32 *tailskip);
 193
 194 #if IS_ENABLED(CONFIG_KUNIT)
 195 void krb5_nfold(u32 inbits, const u8 *in, u32 outbits, u8 *out);
 196 const struct gss_krb5_enctype *gss_krb5_lookup_enctype(u32 etype);
 197 int krb5_cbc_cts_encrypt(struct crypto_sync_skcipher *cts_tfm,
 198                          struct crypto_sync_skcipher *cbc_tfm, u32 offset,
 199                          struct xdr_buf *buf, struct page **pages,
 200                          u8 *iv, unsigned int ivsize);
 201 int krb5_cbc_cts_decrypt(struct crypto_sync_skcipher *cts_tfm,
 202                          struct crypto_sync_skcipher *cbc_tfm,
 203                          u32 offset, struct xdr_buf *buf);
 204 u32 krb5_etm_checksum(struct crypto_sync_skcipher *cipher,
 205                       struct crypto_ahash *tfm, const struct xdr_buf *body,
 206                       int body_offset, struct xdr_netobj *cksumout);
 207 #endif
 208
 209 #endif /* _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H */