bsd/nfs/nfs_gss.h

   1 /*
   2  * Copyright (c) 2007-2010 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 <libkern/crypto/des.h>
  35
  36 #define RPCSEC_GSS                      6
  37 #define RPCSEC_GSS_VERS_1               1
  38
  39 enum rpcsec_gss_proc {
  40         RPCSEC_GSS_DATA                 = 0,
  41         RPCSEC_GSS_INIT                 = 1,
  42         RPCSEC_GSS_CONTINUE_INIT        = 2,
  43         RPCSEC_GSS_DESTROY              = 3
  44 };
  45
  46 enum rpcsec_gss_service {
  47         RPCSEC_GSS_SVC_NONE             = 1,    // sec=krb5
  48         RPCSEC_GSS_SVC_INTEGRITY        = 2,    // sec=krb5i
  49         RPCSEC_GSS_SVC_PRIVACY          = 3,    // sec=krb5p
  50         RPCSEC_GSS_SVC_SYS              = 4     // sec=sys (fallback)
  51 };
  52
  53 /* encoded krb5 OID */
  54 extern u_char krb5_mech[11];
  55
  56 /*
  57  * GSS-API things
  58  */
  59 #define GSS_S_COMPLETE                  0
  60 #define GSS_S_CONTINUE_NEEDED           1
  61
  62 #define GSS_MAXSEQ                      0x80000000      // The biggest sequence number
  63 #define GSS_SVC_MAXCONTEXTS             500000          // Max contexts supported
  64 #define GSS_SVC_SEQWINDOW               256             // Server's sequence window
  65 #define GSS_CLNT_SEQLISTMAX             32              // Max length of req seq num list
  66 #define GSS_CLNT_SYS_VALID              300             // Valid time (sec) for failover ctx
  67
  68
  69 #define SKEYLEN 8                       // length of DES key
  70 #define SKEYLEN3 24                     // length of DES3 keyboard
  71 #define MAX_SKEYLEN     SKEYLEN3
  72
  73 typedef struct {
  74         uint32_t type;          // See defines below
  75         uint32_t keybytes;      // Session key length bytes;
  76         uint32_t hash_len;
  77         u_char   skey[MAX_SKEYLEN];             // Session key;
  78         union {
  79                 struct {
  80                         des_cblock  *key;
  81                         des_cbc_key_schedule gss_sched;
  82                         des_cbc_key_schedule gss_sched_Ke;
  83                 } des;
  84                 struct {
  85                         des_cblock              (*key)[3];
  86                         des_cblock              ckey[3];
  87                         des3_cbc_key_schedule   gss_sched;
  88                 } des3;
  89         } ks_u;
  90 } gss_key_info;
  91
  92 #define NFS_GSS_0DES    0 // Not DES or uninitialized
  93 #define NFS_GSS_1DES    1 // Single DES with DES_MAC_MD5
  94 #define NFS_GSS_3DES    2 // Triple EDE DES KD with SHA1
  95
  96 /*
  97  * The client's RPCSEC_GSS context information
  98  */
  99 struct nfs_gss_clnt_ctx {
 100         lck_mtx_t               *gss_clnt_mtx;
 101         thread_t                gss_clnt_thread;        // Thread creating context
 102         TAILQ_ENTRY(nfs_gss_clnt_ctx)   gss_clnt_entries;
 103         uint32_t                gss_clnt_flags;         // Flag bits - see below
 104         uint32_t                gss_clnt_refcnt;        // Reference count
 105         uid_t                   gss_clnt_uid;           // Owner of this context
 106         uint32_t                gss_clnt_proc;          // Current GSS proc for cred
 107         uint32_t                gss_clnt_seqnum;        // GSS sequence number
 108         uint32_t                gss_clnt_service;       // Indicates krb5, krb5i or krb5p
 109         u_char                  *gss_clnt_handle;       // Identifies server context
 110         uint32_t                gss_clnt_handle_len;    // Size of server's ctx handle
 111         time_t                  gss_clnt_ctime;         // When context was created
 112         uint32_t                gss_clnt_seqwin;        // Server's seq num window
 113         uint32_t                *gss_clnt_seqbits;      // Bitmap to track seq numbers in use
 114         mach_port_t             gss_clnt_mport;         // Mach port for gssd upcall
 115         u_char                  *gss_clnt_verf;         // RPC verifier from server
 116         char                    *gss_clnt_svcname;      // Service name e.g. "nfs/big.apple.com"
 117         gssd_cred               gss_clnt_cred_handle;   // Opaque cred handle from gssd
 118         gssd_ctx                gss_clnt_context;       // Opaque context handle from gssd
 119         u_char                  *gss_clnt_token;        // GSS token exchanged via gssd & server
 120         uint32_t                gss_clnt_tokenlen;      // Length of token
 121         gss_key_info            gss_clnt_kinfo;         // GSS key info
 122         uint32_t                gss_clnt_gssd_flags;    // Special flag bits to gssd
 123         uint32_t                gss_clnt_major;         // GSS major result from gssd or server
 124         uint32_t                gss_clnt_minor;         // GSS minor result from gssd or server
 125 };
 126
 127 /*
 128  * gss_clnt_flags
 129  */
 130 #define GSS_CTX_COMPLETE        0x00000001      // Context is complete
 131 #define GSS_CTX_INVAL           0x00000002      // Context is invalid
 132 #define GSS_NEEDSEQ             0x00000004      // Need a sequence number
 133 #define GSS_NEEDCTX             0x00000008      // Need the context
 134
 135 /*
 136  * The server's RPCSEC_GSS context information
 137  */
 138 struct nfs_gss_svc_ctx {
 139         lck_mtx_t               *gss_svc_mtx;
 140         LIST_ENTRY(nfs_gss_svc_ctx)     gss_svc_entries;
 141         uint32_t                gss_svc_handle;         // Identifies server context to client
 142         uint32_t                gss_svc_refcnt;         // Reference count
 143         uint32_t                gss_svc_proc;           // Current GSS proc from cred
 144         uid_t                   gss_svc_uid;            // UID of this user
 145         gid_t                   gss_svc_gids[NGROUPS];  // GIDs of this user
 146         uint32_t                gss_svc_ngroups;        // Count of gids
 147         uint64_t                gss_svc_incarnation;    // Delete ctx if we exceed this + ttl value
 148         uint32_t                gss_svc_seqmax;         // Current max GSS sequence number
 149         uint32_t                gss_svc_seqwin;         // GSS sequence number window
 150         uint32_t                *gss_svc_seqbits;       // Bitmap to track seq numbers
 151         gssd_cred               gss_svc_cred_handle;    // Opaque cred handle from gssd
 152         gssd_ctx                        gss_svc_context;        // Opaque context handle from gssd
 153         u_char                  *gss_svc_token;         // GSS token exchanged via gssd & client
 154         uint32_t                gss_svc_tokenlen;       // Length of token
 155         gss_key_info            gss_svc_kinfo;          // Session key info
 156         uint32_t                gss_svc_major;          // GSS major result from gssd
 157         uint32_t                gss_svc_minor;          // GSS minor result from gssd
 158 };
 159
 160 #define SVC_CTX_HASHSZ  64
 161 #define SVC_CTX_HASH(handle)    ((handle) % SVC_CTX_HASHSZ)
 162 LIST_HEAD(nfs_gss_svc_ctx_hashhead, nfs_gss_svc_ctx);
 163
 164 /*
 165  * Macros to manipulate bits in the sequence window
 166  */
 167 #define win_getbit(bits, bit)      ((bits[(bit) / 32] &   (1 << (bit) % 32)) != 0)
 168 #define win_setbit(bits, bit)   do { bits[(bit) / 32] |=  (1 << (bit) % 32); } while (0)
 169 #define win_resetbit(bits, bit) do { bits[(bit) / 32] &= ~(1 << (bit) % 32); } while (0)
 170
 171 /*
 172  * Server context stale times
 173  */
 174 #define GSS_CTX_PEND            5               // seconds
 175 #define GSS_CTX_EXPIRE          (8 * 3600)      // seconds
 176 #define GSS_CTX_TTL_MIN         1               // seconds
 177 #define GSS_TIMER_PERIOD        300             // seconds
 178 #define MSECS_PER_SEC           1000
 179
 180 __BEGIN_DECLS
 181
 182 void    nfs_gss_init(void);
 183 int     nfs_gss_clnt_cred_put(struct nfsreq *, struct nfsm_chain *, mbuf_t);
 184 int     nfs_gss_clnt_verf_get(struct nfsreq *, struct nfsm_chain *,
 185                 uint32_t, uint32_t, uint32_t *);
 186 void    nfs_gss_clnt_rpcdone(struct nfsreq *);
 187 int     nfs_gss_clnt_args_restore(struct nfsreq *);
 188 int     nfs_gss_clnt_ctx_renew(struct nfsreq *);
 189 void    nfs_gss_clnt_ctx_ref(struct nfsreq *, struct nfs_gss_clnt_ctx *);
 190 void    nfs_gss_clnt_ctx_unref(struct nfsreq *);
 191 void    nfs_gss_clnt_ctx_unmount(struct nfsmount *);
 192 int     nfs_gss_svc_cred_get(struct nfsrv_descript *, struct nfsm_chain *);
 193 int     nfs_gss_svc_verf_put(struct nfsrv_descript *, struct nfsm_chain *);
 194 int     nfs_gss_svc_ctx_init(struct nfsrv_descript *, struct nfsrv_sock *, mbuf_t *);
 195 int     nfs_gss_svc_prepare_reply(struct nfsrv_descript *, struct nfsm_chain *);
 196 int     nfs_gss_svc_protect_reply(struct nfsrv_descript *, mbuf_t);
 197 void    nfs_gss_svc_ctx_deref(struct nfs_gss_svc_ctx *);
 198 void    nfs_gss_svc_cleanup(void);
 199
 200 __END_DECLS
 201 #endif /* _NFS_NFS_GSS_H_ */