bsd/nfs/nfs_gss.h

   1 /*
   2  * Copyright (c) 2007-2013 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #ifndef _NFS_NFS_GSS_H_
  30 #define _NFS_NFS_GSS_H_
  31
  32 #include <gssd/gssd_mach.h>
  33 #include <sys/param.h>
  34 #include <nfs/nfs_ioctl.h>
  35 #include <libkern/crypto/des.h>
  36
  37 #define RPCSEC_GSS                      6
  38 #define RPCSEC_GSS_VERS_1               1
  39
  40 enum rpcsec_gss_proc {
  41         RPCSEC_GSS_DATA                 = 0,
  42         RPCSEC_GSS_INIT                 = 1,
  43         RPCSEC_GSS_CONTINUE_INIT        = 2,
  44         RPCSEC_GSS_DESTROY              = 3
  45 };
  46
  47 enum rpcsec_gss_service {
  48         RPCSEC_GSS_SVC_NONE             = 1,    // sec=krb5
  49         RPCSEC_GSS_SVC_INTEGRITY        = 2,    // sec=krb5i
  50         RPCSEC_GSS_SVC_PRIVACY          = 3,    // sec=krb5p
  51         RPCSEC_GSS_SVC_SYS              = 4     // sec=sys (fallback)
  52 };
  53
  54 /* encoded krb5 OID */
  55 extern u_char krb5_mech[11];
  56
  57 /*
  58  * GSS-API things
  59  */
  60 typedef uint32_t OM_uint32;
  61
  62 #define GSS_S_COMPLETE                  0
  63 #define GSS_S_CONTINUE_NEEDED           1
  64
  65 /*
  66  * Some "helper" definitions to make the status code macros obvious.
  67  * From gssapi.h:
  68  */
  69 #define GSS_C_CALLING_ERROR_OFFSET 24
  70 #define GSS_C_ROUTINE_ERROR_OFFSET 16
  71 #define GSS_C_SUPPLEMENTARY_OFFSET 0
  72 #define GSS_C_CALLING_ERROR_MASK ((OM_uint32) 0377ul)
  73 #define GSS_C_ROUTINE_ERROR_MASK ((OM_uint32) 0377ul)
  74 #define GSS_C_SUPPLEMENTARY_MASK ((OM_uint32) 0177777ul)
  75
  76 /*
  77  * The macros that test status codes for error conditions.  Note that the
  78  * GSS_ERROR() macro has changed slightly from the V1 GSSAPI so that it now
  79  * evaluates its argument only once.
  80  */
  81 #define GSS_CALLING_ERROR(x) \
  82         ((x) & (GSS_C_CALLING_ERROR_MASK << GSS_C_CALLING_ERROR_OFFSET))
  83 #define GSS_ROUTINE_ERROR(x) \
  84         ((x) & (GSS_C_ROUTINE_ERROR_MASK << GSS_C_ROUTINE_ERROR_OFFSET))
  85 #define GSS_SUPPLEMENTARY_INFO(x) \
  86         ((x) & (GSS_C_SUPPLEMENTARY_MASK << GSS_C_SUPPLEMENTARY_OFFSET))
  87 #define GSS_ERROR(x) \
  88         ((x) & ((GSS_C_CALLING_ERROR_MASK << GSS_C_CALLING_ERROR_OFFSET) | \
  89                 (GSS_C_ROUTINE_ERROR_MASK << GSS_C_ROUTINE_ERROR_OFFSET)))
  90
  91 #define GSS_MAXSEQ                      0x80000000      // The biggest sequence number
  92 #define GSS_SVC_MAXCONTEXTS             500000          // Max contexts supported
  93 #define GSS_SVC_SEQWINDOW               256             // Server's sequence window
  94 #define GSS_CLNT_SEQLISTMAX             32              // Max length of req seq num list
  95 #define GSS_CLNT_SYS_VALID              300             // Valid time (sec) for failover ctx
  96
  97 #define SKEYLEN 8                       // length of DES key
  98 #define SKEYLEN3 24                     // length of DES3 keyboard
  99 #define MAX_SKEYLEN     SKEYLEN3
 100
 101 typedef struct {
 102         uint32_t type;          // See defines below
 103         uint32_t keybytes;      // Session key length bytes;
 104         uint32_t hash_len;
 105         u_char   skey[MAX_SKEYLEN];             // Session key;
 106         union {
 107                 struct {
 108                         des_cblock  *key;
 109                         des_cbc_key_schedule gss_sched;
 110                         des_cbc_key_schedule gss_sched_Ke;
 111                 } des;
 112                 struct {
 113                         des_cblock              (*key)[3];
 114                         des_cblock              ckey[3];
 115                         des3_cbc_key_schedule   gss_sched;
 116                 } des3;
 117         } ks_u;
 118 } gss_key_info;
 119
 120 #define NFS_GSS_0DES    0 // Not DES or uninitialized
 121 #define NFS_GSS_1DES    1 // Single DES with DES_MAC_MD5
 122 #define NFS_GSS_3DES    2 // Triple EDE DES KD with SHA1
 123
 124 /*
 125  * The client's RPCSEC_GSS context information
 126  */
 127 struct nfs_gss_clnt_ctx {
 128         lck_mtx_t               *gss_clnt_mtx;
 129         thread_t                gss_clnt_thread;        // Thread creating context
 130         TAILQ_ENTRY(nfs_gss_clnt_ctx)   gss_clnt_entries;
 131         uint32_t                gss_clnt_flags;         // Flag bits - see below
 132         uint32_t                gss_clnt_refcnt;        // Reference count
 133         kauth_cred_t            gss_clnt_cred;          // Owner of this context
 134         uint8_t                 *gss_clnt_principal;    // Principal to use for this credential
 135         uint32_t                gss_clnt_prinlen;       // Length of principal
 136         gssd_nametype           gss_clnt_prinnt;        // Name type of principal
 137         char                    *gss_clnt_display;      // display name of principal
 138         uint32_t                gss_clnt_proc;          // Current GSS proc for cred
 139         uint32_t                gss_clnt_seqnum;        // GSS sequence number
 140         uint32_t                gss_clnt_service;       // Indicates krb5, krb5i or krb5p
 141         uint8_t                 *gss_clnt_handle;       // Identifies server context
 142         uint32_t                gss_clnt_handle_len;    // Size of server's ctx handle
 143         time_t                  gss_clnt_ctime;         // When context was created
 144         uint32_t                gss_clnt_seqwin;        // Server's seq num window
 145         uint32_t                *gss_clnt_seqbits;      // Bitmap to track seq numbers in use
 146         mach_port_t             gss_clnt_mport;         // Mach port for gssd upcall
 147         uint8_t                 *gss_clnt_verf;         // RPC verifier from server
 148         uint8_t                 *gss_clnt_svcname;      // Service name e.g. "nfs/big.apple.com"
 149         uint32_t                gss_clnt_svcnamlen;     // Service name length
 150         gssd_nametype           gss_clnt_svcnt;         // Service name type
 151         gssd_cred               gss_clnt_cred_handle;   // Opaque cred handle from gssd
 152         gssd_ctx                gss_clnt_context;       // Opaque context handle from gssd
 153         uint8_t                 *gss_clnt_token;        // GSS token exchanged via gssd & server
 154         uint32_t                gss_clnt_tokenlen;      // Length of token
 155         gss_key_info            gss_clnt_kinfo;         // GSS key info
 156         uint32_t                gss_clnt_gssd_flags;    // Special flag bits to gssd
 157         uint32_t                gss_clnt_major;         // GSS major result from gssd or server
 158         uint32_t                gss_clnt_minor;         // GSS minor result from gssd or server
 159 };
 160
 161 /*
 162  * gss_clnt_flags
 163  */
 164 #define GSS_CTX_COMPLETE        0x00000001      // Context is complete
 165 #define GSS_CTX_INVAL           0x00000002      // Context is invalid
 166 #define GSS_CTX_INCOMPLETE      0x00000004      // Context needs to be inited
 167 #define GSS_NEEDSEQ             0x00000008      // Need a sequence number
 168 #define GSS_NEEDCTX             0x00000010      // Need the context
 169
 170 /*
 171  * The server's RPCSEC_GSS context information
 172  */
 173 struct nfs_gss_svc_ctx {
 174         lck_mtx_t               *gss_svc_mtx;
 175         LIST_ENTRY(nfs_gss_svc_ctx)     gss_svc_entries;
 176         uint32_t                gss_svc_handle;         // Identifies server context to client
 177         uint32_t                gss_svc_refcnt;         // Reference count
 178         uint32_t                gss_svc_proc;           // Current GSS proc from cred
 179         uid_t                   gss_svc_uid;            // UID of this user
 180         gid_t                   gss_svc_gids[NGROUPS];  // GIDs of this user
 181         uint32_t                gss_svc_ngroups;        // Count of gids
 182         uint64_t                gss_svc_incarnation;    // Delete ctx if we exceed this + ttl value
 183         uint32_t                gss_svc_seqmax;         // Current max GSS sequence number
 184         uint32_t                gss_svc_seqwin;         // GSS sequence number window
 185         uint32_t                *gss_svc_seqbits;       // Bitmap to track seq numbers
 186         gssd_cred               gss_svc_cred_handle;    // Opaque cred handle from gssd
 187         gssd_ctx                gss_svc_context;        // Opaque context handle from gssd
 188         u_char                  *gss_svc_token;         // GSS token exchanged via gssd & client
 189         uint32_t                gss_svc_tokenlen;       // Length of token
 190         gss_key_info            gss_svc_kinfo;          // Session key info
 191         uint32_t                gss_svc_major;          // GSS major result from gssd
 192         uint32_t                gss_svc_minor;          // GSS minor result from gssd
 193 };
 194
 195 #define SVC_CTX_HASHSZ  64
 196 #define SVC_CTX_HASH(handle)    ((handle) % SVC_CTX_HASHSZ)
 197 LIST_HEAD(nfs_gss_svc_ctx_hashhead, nfs_gss_svc_ctx);
 198
 199 /*
 200  * Macros to manipulate bits in the sequence window
 201  */
 202 #define win_getbit(bits, bit)      ((bits[(bit) / 32] &   (1 << (bit) % 32)) != 0)
 203 #define win_setbit(bits, bit)   do { bits[(bit) / 32] |=  (1 << (bit) % 32); } while (0)
 204 #define win_resetbit(bits, bit) do { bits[(bit) / 32] &= ~(1 << (bit) % 32); } while (0)
 205
 206 /*
 207  * Server context stale times
 208  */
 209 #define GSS_CTX_PEND            5               // seconds
 210 #define GSS_CTX_EXPIRE          (8 * 3600)      // seconds
 211 #define GSS_CTX_TTL_MIN         1               // seconds
 212 #define GSS_TIMER_PERIOD        300             // seconds
 213 #define MSECS_PER_SEC           1000
 214
 215 __BEGIN_DECLS
 216
 217 void    nfs_gss_init(void);
 218 int     nfs_gss_clnt_cred_put(struct nfsreq *, struct nfsm_chain *, mbuf_t);
 219 int     nfs_gss_clnt_verf_get(struct nfsreq *, struct nfsm_chain *,
 220                 uint32_t, uint32_t, uint32_t *);
 221 void    nfs_gss_clnt_rpcdone(struct nfsreq *);
 222 int     nfs_gss_clnt_args_restore(struct nfsreq *);
 223 int     nfs_gss_clnt_ctx_renew(struct nfsreq *);
 224 void    nfs_gss_clnt_ctx_ref(struct nfsreq *, struct nfs_gss_clnt_ctx *);
 225 void    nfs_gss_clnt_ctx_unref(struct nfsreq *);
 226 void    nfs_gss_clnt_ctx_unmount(struct nfsmount *);
 227 int     nfs_gss_clnt_ctx_destroy(struct nfsmount *, kauth_cred_t cred);
 228 int     nfs_gss_svc_cred_get(struct nfsrv_descript *, struct nfsm_chain *);
 229 int     nfs_gss_svc_verf_put(struct nfsrv_descript *, struct nfsm_chain *);
 230 int     nfs_gss_svc_ctx_init(struct nfsrv_descript *, struct nfsrv_sock *, mbuf_t *);
 231 int     nfs_gss_svc_prepare_reply(struct nfsrv_descript *, struct nfsm_chain *);
 232 int     nfs_gss_svc_protect_reply(struct nfsrv_descript *, mbuf_t);
 233 void    nfs_gss_svc_ctx_deref(struct nfs_gss_svc_ctx *);
 234 void    nfs_gss_svc_cleanup(void);
 235
 236 __END_DECLS
 237 #endif /* _NFS_NFS_GSS_H_ */