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