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 DEFINE_SPINLOCK(registered_mechs_lock);
  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(const 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                                 gm = pos;
 155                         break;
 156                 }
 157         }
 158         spin_unlock(&registered_mechs_lock);
 159         return gm;
 160
 161 }
 162
 163 EXPORT_SYMBOL(gss_mech_get_by_name);
 164
 165 static inline int
 166 mech_supports_pseudoflavor(struct gss_api_mech *gm, u32 pseudoflavor)
 167 {
 168         int i;
 169
 170         for (i = 0; i < gm->gm_pf_num; i++) {
 171                 if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
 172                         return 1;
 173         }
 174         return 0;
 175 }
 176
 177 struct gss_api_mech *
 178 gss_mech_get_by_pseudoflavor(u32 pseudoflavor)
 179 {
 180         struct gss_api_mech *pos, *gm = NULL;
 181
 182         spin_lock(&registered_mechs_lock);
 183         list_for_each_entry(pos, &registered_mechs, gm_list) {
 184                 if (!mech_supports_pseudoflavor(pos, pseudoflavor)) {
 185                         module_put(pos->gm_owner);
 186                         continue;
 187                 }
 188                 if (try_module_get(pos->gm_owner))
 189                         gm = pos;
 190                 break;
 191         }
 192         spin_unlock(&registered_mechs_lock);
 193         return gm;
 194 }
 195
 196 EXPORT_SYMBOL(gss_mech_get_by_pseudoflavor);
 197
 198 u32
 199 gss_pseudoflavor_to_service(struct gss_api_mech *gm, u32 pseudoflavor)
 200 {
 201         int i;
 202
 203         for (i = 0; i < gm->gm_pf_num; i++) {
 204                 if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
 205                         return gm->gm_pfs[i].service;
 206         }
 207         return 0;
 208 }
 209
 210 EXPORT_SYMBOL(gss_pseudoflavor_to_service);
 211
 212 char *
 213 gss_service_to_auth_domain_name(struct gss_api_mech *gm, u32 service)
 214 {
 215         int i;
 216
 217         for (i = 0; i < gm->gm_pf_num; i++) {
 218                 if (gm->gm_pfs[i].service == service)
 219                         return gm->gm_pfs[i].auth_domain_name;
 220         }
 221         return NULL;
 222 }
 223
 224 EXPORT_SYMBOL(gss_service_to_auth_domain_name);
 225
 226 void
 227 gss_mech_put(struct gss_api_mech * gm)
 228 {
 229         module_put(gm->gm_owner);
 230 }
 231
 232 EXPORT_SYMBOL(gss_mech_put);
 233
 234 /* The mech could probably be determined from the token instead, but it's just
 235  * as easy for now to pass it in. */
 236 int
 237 gss_import_sec_context(const void *input_token, size_t bufsize,
 238                        struct gss_api_mech      *mech,
 239                        struct gss_ctx           **ctx_id)
 240 {
 241         if (!(*ctx_id = kmalloc(sizeof(**ctx_id), GFP_KERNEL)))
 242                 return GSS_S_FAILURE;
 243         memset(*ctx_id, 0, sizeof(**ctx_id));
 244         (*ctx_id)->mech_type = gss_mech_get(mech);
 245
 246         return mech->gm_ops
 247                 ->gss_import_sec_context(input_token, bufsize, *ctx_id);
 248 }
 249
 250 /* gss_get_mic: compute a mic over message and return mic_token. */
 251
 252 u32
 253 gss_get_mic(struct gss_ctx      *context_handle,
 254             u32                 qop,
 255             struct xdr_buf      *message,
 256             struct xdr_netobj   *mic_token)
 257 {
 258          return context_handle->mech_type->gm_ops
 259                 ->gss_get_mic(context_handle,
 260                               qop,
 261                               message,
 262                               mic_token);
 263 }
 264
 265 /* gss_verify_mic: check whether the provided mic_token verifies message. */
 266
 267 u32
 268 gss_verify_mic(struct gss_ctx           *context_handle,
 269                struct xdr_buf           *message,
 270                struct xdr_netobj        *mic_token,
 271                u32                      *qstate)
 272 {
 273         return context_handle->mech_type->gm_ops
 274                 ->gss_verify_mic(context_handle,
 275                                  message,
 276                                  mic_token,
 277                                  qstate);
 278 }
 279
 280 /* gss_delete_sec_context: free all resources associated with context_handle.
 281  * Note this differs from the RFC 2744-specified prototype in that we don't
 282  * bother returning an output token, since it would never be used anyway. */
 283
 284 u32
 285 gss_delete_sec_context(struct gss_ctx   **context_handle)
 286 {
 287         dprintk("RPC:      gss_delete_sec_context deleting %p\n",
 288                         *context_handle);
 289
 290         if (!*context_handle)
 291                 return(GSS_S_NO_CONTEXT);
 292         if ((*context_handle)->internal_ctx_id != 0)
 293                 (*context_handle)->mech_type->gm_ops
 294                         ->gss_delete_sec_context((*context_handle)
 295                                                         ->internal_ctx_id);
 296         if ((*context_handle)->mech_type)
 297                 gss_mech_put((*context_handle)->mech_type);
 298         kfree(*context_handle);
 299         *context_handle=NULL;
 300         return GSS_S_COMPLETE;
 301 }