net/sunrpc/auth_gss/gss_mech_switch.c

   1 /*
   2  *  linux/net/sunrpc/gss_mech_switch.c
   3  *
   4  *  Copyright (c) 2001 The Regents of the University of Michigan.
   5  *  All rights reserved.
   6  *
   7  *  J. Bruce Fields   <bfields@umich.edu>
   8  *
   9  *  Redistribution and use in source and binary forms, with or without
  10  *  modification, are permitted provided that the following conditions
  11  *  are met:
  12  *
  13  *  1. Redistributions of source code must retain the above copyright
  14  *     notice, this list of conditions and the following disclaimer.
  15  *  2. Redistributions in binary form must reproduce the above copyright
  16  *     notice, this list of conditions and the following disclaimer in the
  17  *     documentation and/or other materials provided with the distribution.
  18  *  3. Neither the name of the University nor the names of its
  19  *     contributors may be used to endorse or promote products derived
  20  *     from this software without specific prior written permission.
  21  *
  22  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  23  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  24  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  25  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  27  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  28  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  29  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  30  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  31  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  32  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  *
  34  */
  35
  36 #include <linux/types.h>
  37 #include <linux/slab.h>
  38 #include <linux/socket.h>
  39 #include <linux/module.h>
  40 #include <linux/sunrpc/msg_prot.h>
  41 #include <linux/sunrpc/gss_asn1.h>
  42 #include <linux/sunrpc/auth_gss.h>
  43 #include <linux/sunrpc/svcauth_gss.h>
  44 #include <linux/sunrpc/gss_err.h>
  45 #include <linux/sunrpc/sched.h>
  46 #include <linux/sunrpc/gss_api.h>
  47 #include <linux/sunrpc/clnt.h>
  48
  49 #ifdef RPC_DEBUG
  50 # define RPCDBG_FACILITY        RPCDBG_AUTH
  51 #endif
  52
  53 static LIST_HEAD(registered_mechs);
  54 static spinlock_t registered_mechs_lock = SPIN_LOCK_UNLOCKED;
  55
  56 static void
  57 gss_mech_free(struct gss_api_mech *gm)
  58 {
  59         struct pf_desc *pf;
  60         int i;
  61
  62         for (i = 0; i < gm->gm_pf_num; i++) {
  63                 pf = &gm->gm_pfs[i];
  64                 if (pf->auth_domain_name)
  65                         kfree(pf->auth_domain_name);
  66                 pf->auth_domain_name = NULL;
  67         }
  68 }
  69
  70 static inline char *
  71 make_auth_domain_name(char *name)
  72 {
  73         static char     *prefix = "gss/";
  74         char            *new;
  75
  76         new = kmalloc(strlen(name) + strlen(prefix) + 1, GFP_KERNEL);
  77         if (new) {
  78                 strcpy(new, prefix);
  79                 strcat(new, name);
  80         }
  81         return new;
  82 }
  83
  84 static int
  85 gss_mech_svc_setup(struct gss_api_mech *gm)
  86 {
  87         struct pf_desc *pf;
  88         int i, status;
  89
  90         for (i = 0; i < gm->gm_pf_num; i++) {
  91                 pf = &gm->gm_pfs[i];
  92                 pf->auth_domain_name = make_auth_domain_name(pf->name);
  93                 status = -ENOMEM;
  94                 if (pf->auth_domain_name == NULL)
  95                         goto out;
  96                 status = svcauth_gss_register_pseudoflavor(pf->pseudoflavor,
  97                                                         pf->auth_domain_name);
  98                 if (status)
  99                         goto out;
 100         }
 101         return 0;
 102 out:
 103         gss_mech_free(gm);
 104         return status;
 105 }
 106
 107 int
 108 gss_mech_register(struct gss_api_mech *gm)
 109 {
 110         int status;
 111
 112         status = gss_mech_svc_setup(gm);
 113         if (status)
 114                 return status;
 115         spin_lock(&registered_mechs_lock);
 116         list_add(&gm->gm_list, &registered_mechs);
 117         spin_unlock(&registered_mechs_lock);
 118         dprintk("RPC:      registered gss mechanism %s\n", gm->gm_name);
 119         return 0;
 120 }
 121
 122 EXPORT_SYMBOL(gss_mech_register);
 123
 124 void
 125 gss_mech_unregister(struct gss_api_mech *gm)
 126 {
 127         spin_lock(&registered_mechs_lock);
 128         list_del(&gm->gm_list);
 129         spin_unlock(&registered_mechs_lock);
 130         dprintk("RPC:      unregistered gss mechanism %s\n", gm->gm_name);
 131         gss_mech_free(gm);
 132 }
 133
 134 EXPORT_SYMBOL(gss_mech_unregister);
 135
 136 struct gss_api_mech *
 137 gss_mech_get(struct gss_api_mech *gm)
 138 {
 139         __module_get(gm->gm_owner);
 140         return gm;
 141 }
 142
 143 EXPORT_SYMBOL(gss_mech_get);
 144
 145 struct gss_api_mech *
 146 gss_mech_get_by_name(char *name)
 147 {
 148         struct gss_api_mech     *pos, *gm = NULL;
 149
 150         spin_lock(&registered_mechs_lock);
 151         list_for_each_entry(pos, &registered_mechs, gm_list) {
 152                 if (0 == strcmp(name, pos->gm_name)) {
 153                         if (!try_module_get(pos->gm_owner))
 154                                 continue;
 155                         gm = pos;
 156                         break;
 157                 }
 158         }
 159         spin_unlock(&registered_mechs_lock);
 160         return gm;
 161
 162 }
 163
 164 EXPORT_SYMBOL(gss_mech_get_by_name);
 165
 166 static inline int
 167 mech_supports_pseudoflavor(struct gss_api_mech *gm, u32 pseudoflavor)
 168 {
 169         int i;
 170
 171         for (i = 0; i < gm->gm_pf_num; i++) {
 172                 if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
 173                         return 1;
 174         }
 175         return 0;
 176 }
 177
 178 struct gss_api_mech *
 179 gss_mech_get_by_pseudoflavor(u32 pseudoflavor)
 180 {
 181         struct gss_api_mech *pos, *gm = NULL;
 182
 183         spin_lock(&registered_mechs_lock);
 184         list_for_each_entry(pos, &registered_mechs, gm_list) {
 185                 if (!try_module_get(pos->gm_owner))
 186                         continue;
 187                 if (!mech_supports_pseudoflavor(pos, pseudoflavor)) {
 188                         module_put(pos->gm_owner);
 189                         continue;
 190                 }
 191                 gm = pos;
 192                 break;
 193         }
 194         spin_unlock(&registered_mechs_lock);
 195         return gm;
 196 }
 197
 198 EXPORT_SYMBOL(gss_mech_get_by_pseudoflavor);
 199
 200 u32
 201 gss_pseudoflavor_to_service(struct gss_api_mech *gm, u32 pseudoflavor)
 202 {
 203         int i;
 204
 205         for (i = 0; i < gm->gm_pf_num; i++) {
 206                 if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
 207                         return gm->gm_pfs[i].service;
 208         }
 209         return 0;
 210 }
 211
 212 EXPORT_SYMBOL(gss_pseudoflavor_to_service);
 213
 214 char *
 215 gss_service_to_auth_domain_name(struct gss_api_mech *gm, u32 service)
 216 {
 217         int i;
 218
 219         for (i = 0; i < gm->gm_pf_num; i++) {
 220                 if (gm->gm_pfs[i].service == service)
 221                         return gm->gm_pfs[i].auth_domain_name;
 222         }
 223         return NULL;
 224 }
 225
 226 EXPORT_SYMBOL(gss_service_to_auth_domain_name);
 227
 228 void
 229 gss_mech_put(struct gss_api_mech * gm)
 230 {
 231         module_put(gm->gm_owner);
 232 }
 233
 234 EXPORT_SYMBOL(gss_mech_put);
 235
 236 /* The mech could probably be determined from the token instead, but it's just
 237  * as easy for now to pass it in. */
 238 u32
 239 gss_import_sec_context(struct xdr_netobj        *input_token,
 240                        struct gss_api_mech      *mech,
 241                        struct gss_ctx           **ctx_id)
 242 {
 243         if (!(*ctx_id = kmalloc(sizeof(**ctx_id), GFP_KERNEL)))
 244                 return GSS_S_FAILURE;
 245         memset(*ctx_id, 0, sizeof(**ctx_id));
 246         (*ctx_id)->mech_type = gss_mech_get(mech);
 247
 248         return mech->gm_ops
 249                 ->gss_import_sec_context(input_token, *ctx_id);
 250 }
 251
 252 /* gss_get_mic: compute a mic over message and return mic_token. */
 253
 254 u32
 255 gss_get_mic(struct gss_ctx      *context_handle,
 256             u32                 qop,
 257             struct xdr_buf      *message,
 258             struct xdr_netobj   *mic_token)
 259 {
 260          return context_handle->mech_type->gm_ops
 261                 ->gss_get_mic(context_handle,
 262                               qop,
 263                               message,
 264                               mic_token);
 265 }
 266
 267 /* gss_verify_mic: check whether the provided mic_token verifies message. */
 268
 269 u32
 270 gss_verify_mic(struct gss_ctx           *context_handle,
 271                struct xdr_buf           *message,
 272                struct xdr_netobj        *mic_token,
 273                u32                      *qstate)
 274 {
 275         return context_handle->mech_type->gm_ops
 276                 ->gss_verify_mic(context_handle,
 277                                  message,
 278                                  mic_token,
 279                                  qstate);
 280 }
 281
 282 /* gss_delete_sec_context: free all resources associated with context_handle.
 283  * Note this differs from the RFC 2744-specified prototype in that we don't
 284  * bother returning an output token, since it would never be used anyway. */
 285
 286 u32
 287 gss_delete_sec_context(struct gss_ctx   **context_handle)
 288 {
 289         dprintk("RPC:      gss_delete_sec_context deleting %p\n",
 290                         *context_handle);
 291
 292         if (!*context_handle)
 293                 return(GSS_S_NO_CONTEXT);
 294         if ((*context_handle)->internal_ctx_id != 0)
 295                 (*context_handle)->mech_type->gm_ops
 296                         ->gss_delete_sec_context((*context_handle)
 297                                                         ->internal_ctx_id);
 298         if ((*context_handle)->mech_type)
 299                 gss_mech_put((*context_handle)->mech_type);
 300         kfree(*context_handle);
 301         *context_handle=NULL;
 302         return GSS_S_COMPLETE;
 303 }