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/module.h>
  39 #include <linux/sunrpc/msg_prot.h>
  40 #include <linux/sunrpc/gss_asn1.h>
  41 #include <linux/sunrpc/auth_gss.h>
  42 #include <linux/sunrpc/svcauth_gss.h>
  43 #include <linux/sunrpc/gss_err.h>
  44 #include <linux/sunrpc/sched.h>
  45 #include <linux/sunrpc/gss_api.h>
  46 #include <linux/sunrpc/clnt.h>
  47
  48 #ifdef RPC_DEBUG
  49 # define RPCDBG_FACILITY        RPCDBG_AUTH
  50 #endif
  51
  52 static LIST_HEAD(registered_mechs);
  53 static DEFINE_SPINLOCK(registered_mechs_lock);
  54
  55 static void
  56 gss_mech_free(struct gss_api_mech *gm)
  57 {
  58         struct pf_desc *pf;
  59         int i;
  60
  61         for (i = 0; i < gm->gm_pf_num; i++) {
  62                 pf = &gm->gm_pfs[i];
  63                 if (pf->auth_domain_name)
  64                         kfree(pf->auth_domain_name);
  65                 pf->auth_domain_name = NULL;
  66         }
  67 }
  68
  69 static inline char *
  70 make_auth_domain_name(char *name)
  71 {
  72         static char     *prefix = "gss/";
  73         char            *new;
  74
  75         new = kmalloc(strlen(name) + strlen(prefix) + 1, GFP_KERNEL);
  76         if (new) {
  77                 strcpy(new, prefix);
  78                 strcat(new, name);
  79         }
  80         return new;
  81 }
  82
  83 static int
  84 gss_mech_svc_setup(struct gss_api_mech *gm)
  85 {
  86         struct pf_desc *pf;
  87         int i, status;
  88
  89         for (i = 0; i < gm->gm_pf_num; i++) {
  90                 pf = &gm->gm_pfs[i];
  91                 pf->auth_domain_name = make_auth_domain_name(pf->name);
  92                 status = -ENOMEM;
  93                 if (pf->auth_domain_name == NULL)
  94                         goto out;
  95                 status = svcauth_gss_register_pseudoflavor(pf->pseudoflavor,
  96                                                         pf->auth_domain_name);
  97                 if (status)
  98                         goto out;
  99         }
 100         return 0;
 101 out:
 102         gss_mech_free(gm);
 103         return status;
 104 }
 105
 106 int
 107 gss_mech_register(struct gss_api_mech *gm)
 108 {
 109         int status;
 110
 111         status = gss_mech_svc_setup(gm);
 112         if (status)
 113                 return status;
 114         spin_lock(&registered_mechs_lock);
 115         list_add(&gm->gm_list, &registered_mechs);
 116         spin_unlock(&registered_mechs_lock);
 117         dprintk("RPC:      registered gss mechanism %s\n", gm->gm_name);
 118         return 0;
 119 }
 120
 121 EXPORT_SYMBOL(gss_mech_register);
 122
 123 void
 124 gss_mech_unregister(struct gss_api_mech *gm)
 125 {
 126         spin_lock(&registered_mechs_lock);
 127         list_del(&gm->gm_list);
 128         spin_unlock(&registered_mechs_lock);
 129         dprintk("RPC:      unregistered gss mechanism %s\n", gm->gm_name);
 130         gss_mech_free(gm);
 131 }
 132
 133 EXPORT_SYMBOL(gss_mech_unregister);
 134
 135 struct gss_api_mech *
 136 gss_mech_get(struct gss_api_mech *gm)
 137 {
 138         __module_get(gm->gm_owner);
 139         return gm;
 140 }
 141
 142 EXPORT_SYMBOL(gss_mech_get);
 143
 144 struct gss_api_mech *
 145 gss_mech_get_by_name(const char *name)
 146 {
 147         struct gss_api_mech     *pos, *gm = NULL;
 148
 149         spin_lock(&registered_mechs_lock);
 150         list_for_each_entry(pos, &registered_mechs, gm_list) {
 151                 if (0 == strcmp(name, pos->gm_name)) {
 152                         if (try_module_get(pos->gm_owner))
 153                                 gm = pos;
 154                         break;
 155                 }
 156         }
 157         spin_unlock(&registered_mechs_lock);
 158         return gm;
 159
 160 }
 161
 162 EXPORT_SYMBOL(gss_mech_get_by_name);
 163
 164 static inline int
 165 mech_supports_pseudoflavor(struct gss_api_mech *gm, u32 pseudoflavor)
 166 {
 167         int i;
 168
 169         for (i = 0; i < gm->gm_pf_num; i++) {
 170                 if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
 171                         return 1;
 172         }
 173         return 0;
 174 }
 175
 176 struct gss_api_mech *
 177 gss_mech_get_by_pseudoflavor(u32 pseudoflavor)
 178 {
 179         struct gss_api_mech *pos, *gm = NULL;
 180
 181         spin_lock(&registered_mechs_lock);
 182         list_for_each_entry(pos, &registered_mechs, gm_list) {
 183                 if (!mech_supports_pseudoflavor(pos, pseudoflavor)) {
 184                         module_put(pos->gm_owner);
 185                         continue;
 186                 }
 187                 if (try_module_get(pos->gm_owner))
 188                         gm = pos;
 189                 break;
 190         }
 191         spin_unlock(&registered_mechs_lock);
 192         return gm;
 193 }
 194
 195 EXPORT_SYMBOL(gss_mech_get_by_pseudoflavor);
 196
 197 u32
 198 gss_pseudoflavor_to_service(struct gss_api_mech *gm, u32 pseudoflavor)
 199 {
 200         int i;
 201
 202         for (i = 0; i < gm->gm_pf_num; i++) {
 203                 if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
 204                         return gm->gm_pfs[i].service;
 205         }
 206         return 0;
 207 }
 208
 209 EXPORT_SYMBOL(gss_pseudoflavor_to_service);
 210
 211 char *
 212 gss_service_to_auth_domain_name(struct gss_api_mech *gm, u32 service)
 213 {
 214         int i;
 215
 216         for (i = 0; i < gm->gm_pf_num; i++) {
 217                 if (gm->gm_pfs[i].service == service)
 218                         return gm->gm_pfs[i].auth_domain_name;
 219         }
 220         return NULL;
 221 }
 222
 223 EXPORT_SYMBOL(gss_service_to_auth_domain_name);
 224
 225 void
 226 gss_mech_put(struct gss_api_mech * gm)
 227 {
 228         module_put(gm->gm_owner);
 229 }
 230
 231 EXPORT_SYMBOL(gss_mech_put);
 232
 233 /* The mech could probably be determined from the token instead, but it's just
 234  * as easy for now to pass it in. */
 235 int
 236 gss_import_sec_context(const void *input_token, size_t bufsize,
 237                        struct gss_api_mech      *mech,
 238                        struct gss_ctx           **ctx_id)
 239 {
 240         if (!(*ctx_id = kmalloc(sizeof(**ctx_id), GFP_KERNEL)))
 241                 return GSS_S_FAILURE;
 242         memset(*ctx_id, 0, sizeof(**ctx_id));
 243         (*ctx_id)->mech_type = gss_mech_get(mech);
 244
 245         return mech->gm_ops
 246                 ->gss_import_sec_context(input_token, bufsize, *ctx_id);
 247 }
 248
 249 /* gss_get_mic: compute a mic over message and return mic_token. */
 250
 251 u32
 252 gss_get_mic(struct gss_ctx      *context_handle,
 253             struct xdr_buf      *message,
 254             struct xdr_netobj   *mic_token)
 255 {
 256          return context_handle->mech_type->gm_ops
 257                 ->gss_get_mic(context_handle,
 258                               message,
 259                               mic_token);
 260 }
 261
 262 /* gss_verify_mic: check whether the provided mic_token verifies message. */
 263
 264 u32
 265 gss_verify_mic(struct gss_ctx           *context_handle,
 266                struct xdr_buf           *message,
 267                struct xdr_netobj        *mic_token)
 268 {
 269         return context_handle->mech_type->gm_ops
 270                 ->gss_verify_mic(context_handle,
 271                                  message,
 272                                  mic_token);
 273 }
 274
 275 u32
 276 gss_wrap(struct gss_ctx *ctx_id,
 277          int            offset,
 278          struct xdr_buf *buf,
 279          struct page    **inpages)
 280 {
 281         return ctx_id->mech_type->gm_ops
 282                 ->gss_wrap(ctx_id, offset, buf, inpages);
 283 }
 284
 285 u32
 286 gss_unwrap(struct gss_ctx       *ctx_id,
 287            int                  offset,
 288            struct xdr_buf       *buf)
 289 {
 290         return ctx_id->mech_type->gm_ops
 291                 ->gss_unwrap(ctx_id, offset, buf);
 292 }
 293
 294
 295 /* gss_delete_sec_context: free all resources associated with context_handle.
 296  * Note this differs from the RFC 2744-specified prototype in that we don't
 297  * bother returning an output token, since it would never be used anyway. */
 298
 299 u32
 300 gss_delete_sec_context(struct gss_ctx   **context_handle)
 301 {
 302         dprintk("RPC:      gss_delete_sec_context deleting %p\n",
 303                         *context_handle);
 304
 305         if (!*context_handle)
 306                 return(GSS_S_NO_CONTEXT);
 307         if ((*context_handle)->internal_ctx_id != 0)
 308                 (*context_handle)->mech_type->gm_ops
 309                         ->gss_delete_sec_context((*context_handle)
 310                                                         ->internal_ctx_id);
 311         if ((*context_handle)->mech_type)
 312                 gss_mech_put((*context_handle)->mech_type);
 313         kfree(*context_handle);
 314         *context_handle=NULL;
 315         return GSS_S_COMPLETE;
 316 }