lib/krb5/replay.c

   1 /*
   2  * Copyright (c) 1997-2001 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "krb5_locl.h"
  35 #include <vis.h>
  36
  37 struct krb5_rcache_data {
  38     char *name;
  39 };
  40
  41 krb5_error_code KRB5_LIB_FUNCTION
  42 krb5_rc_resolve(krb5_context context,
  43                 krb5_rcache id,
  44                 const char *name)
  45 {
  46     id->name = strdup(name);
  47     if(id->name == NULL) {
  48         krb5_set_error_message(context, KRB5_RC_MALLOC,
  49                                N_("malloc: out of memory", ""));
  50         return KRB5_RC_MALLOC;
  51     }
  52     return 0;
  53 }
  54
  55 krb5_error_code KRB5_LIB_FUNCTION
  56 krb5_rc_resolve_type(krb5_context context,
  57                      krb5_rcache *id,
  58                      const char *type)
  59 {
  60     *id = NULL;
  61     if(strcmp(type, "FILE")) {
  62         krb5_set_error_message (context, KRB5_RC_TYPE_NOTFOUND,
  63                                 N_("replay cache type %s not supported", ""),
  64                                 type);
  65         return KRB5_RC_TYPE_NOTFOUND;
  66     }
  67     *id = calloc(1, sizeof(**id));
  68     if(*id == NULL) {
  69         krb5_set_error_message(context, KRB5_RC_MALLOC,
  70                                N_("malloc: out of memory", ""));
  71         return KRB5_RC_MALLOC;
  72     }
  73     return 0;
  74 }
  75
  76 krb5_error_code KRB5_LIB_FUNCTION
  77 krb5_rc_resolve_full(krb5_context context,
  78                      krb5_rcache *id,
  79                      const char *string_name)
  80 {
  81     krb5_error_code ret;
  82
  83     *id = NULL;
  84
  85     if(strncmp(string_name, "FILE:", 5)) {
  86         krb5_set_error_message(context, KRB5_RC_TYPE_NOTFOUND,
  87                                N_("replay cache type %s not supported", ""),
  88                                string_name);
  89         return KRB5_RC_TYPE_NOTFOUND;
  90     }
  91     ret = krb5_rc_resolve_type(context, id, "FILE");
  92     if(ret)
  93         return ret;
  94     ret = krb5_rc_resolve(context, *id, string_name + 5);
  95     if (ret) {
  96         krb5_rc_close(context, *id);
  97         *id = NULL;
  98     }
  99     return ret;
 100 }
 101
 102 const char* KRB5_LIB_FUNCTION
 103 krb5_rc_default_name(krb5_context context)
 104 {
 105     return "FILE:/var/run/default_rcache";
 106 }
 107
 108 const char* KRB5_LIB_FUNCTION
 109 krb5_rc_default_type(krb5_context context)
 110 {
 111     return "FILE";
 112 }
 113
 114 krb5_error_code KRB5_LIB_FUNCTION
 115 krb5_rc_default(krb5_context context,
 116                 krb5_rcache *id)
 117 {
 118     return krb5_rc_resolve_full(context, id, krb5_rc_default_name(context));
 119 }
 120
 121 struct rc_entry{
 122     time_t stamp;
 123     unsigned char data[16];
 124 };
 125
 126 krb5_error_code KRB5_LIB_FUNCTION
 127 krb5_rc_initialize(krb5_context context,
 128                    krb5_rcache id,
 129                    krb5_deltat auth_lifespan)
 130 {
 131     FILE *f = fopen(id->name, "w");
 132     struct rc_entry tmp;
 133     int ret;
 134
 135     if(f == NULL) {
 136         ret = errno;
 137         krb5_set_error_message(context, ret, "open(%s): %s", id->name,
 138                                strerror(ret));
 139         return ret;
 140     }
 141     tmp.stamp = auth_lifespan;
 142     fwrite(&tmp, 1, sizeof(tmp), f);
 143     fclose(f);
 144     return 0;
 145 }
 146
 147 krb5_error_code KRB5_LIB_FUNCTION
 148 krb5_rc_recover(krb5_context context,
 149                 krb5_rcache id)
 150 {
 151     return 0;
 152 }
 153
 154 krb5_error_code KRB5_LIB_FUNCTION
 155 krb5_rc_destroy(krb5_context context,
 156                 krb5_rcache id)
 157 {
 158     int ret;
 159
 160     if(remove(id->name) < 0) {
 161         ret = errno;
 162         krb5_set_error_message(context, ret, "remove(%s): %s", id->name,
 163                                strerror(ret));
 164         return ret;
 165     }
 166     return krb5_rc_close(context, id);
 167 }
 168
 169 krb5_error_code KRB5_LIB_FUNCTION
 170 krb5_rc_close(krb5_context context,
 171               krb5_rcache id)
 172 {
 173     free(id->name);
 174     free(id);
 175     return 0;
 176 }
 177
 178 static void
 179 checksum_authenticator(Authenticator *auth, void *data)
 180 {
 181     MD5_CTX md5;
 182     int i;
 183
 184     MD5_Init (&md5);
 185     MD5_Update (&md5, auth->crealm, strlen(auth->crealm));
 186     for(i = 0; i < auth->cname.name_string.len; i++)
 187         MD5_Update(&md5, auth->cname.name_string.val[i],
 188                    strlen(auth->cname.name_string.val[i]));
 189     MD5_Update (&md5, &auth->ctime, sizeof(auth->ctime));
 190     MD5_Update (&md5, &auth->cusec, sizeof(auth->cusec));
 191     MD5_Final (data, &md5);
 192 }
 193
 194 krb5_error_code KRB5_LIB_FUNCTION
 195 krb5_rc_store(krb5_context context,
 196               krb5_rcache id,
 197               krb5_donot_replay *rep)
 198 {
 199     struct rc_entry ent, tmp;
 200     time_t t;
 201     FILE *f;
 202     int ret;
 203
 204     ent.stamp = time(NULL);
 205     checksum_authenticator(rep, ent.data);
 206     f = fopen(id->name, "r");
 207     if(f == NULL) {
 208         ret = errno;
 209         krb5_set_error_message(context, ret, "open(%s): %s", id->name,
 210                                strerror(ret));
 211         return ret;
 212     }
 213     rk_cloexec_file(f);
 214     fread(&tmp, sizeof(ent), 1, f);
 215     t = ent.stamp - tmp.stamp;
 216     while(fread(&tmp, sizeof(ent), 1, f)){
 217         if(tmp.stamp < t)
 218             continue;
 219         if(memcmp(tmp.data, ent.data, sizeof(ent.data)) == 0){
 220             fclose(f);
 221             krb5_clear_error_message (context);
 222             return KRB5_RC_REPLAY;
 223         }
 224     }
 225     if(ferror(f)){
 226         ret = errno;
 227         fclose(f);
 228         krb5_set_error_message(context, ret, "%s: %s",
 229                                id->name, strerror(ret));
 230         return ret;
 231     }
 232     fclose(f);
 233     f = fopen(id->name, "a");
 234     if(f == NULL) {
 235         krb5_set_error_message(context, KRB5_RC_IO_UNKNOWN,
 236                                "open(%s): %s", id->name,
 237                                strerror(errno));
 238         return KRB5_RC_IO_UNKNOWN;
 239     }
 240     fwrite(&ent, 1, sizeof(ent), f);
 241     fclose(f);
 242     return 0;
 243 }
 244
 245 krb5_error_code KRB5_LIB_FUNCTION
 246 krb5_rc_expunge(krb5_context context,
 247                 krb5_rcache id)
 248 {
 249     return 0;
 250 }
 251
 252 krb5_error_code KRB5_LIB_FUNCTION
 253 krb5_rc_get_lifespan(krb5_context context,
 254                      krb5_rcache id,
 255                      krb5_deltat *auth_lifespan)
 256 {
 257     FILE *f = fopen(id->name, "r");
 258     int r;
 259     struct rc_entry ent;
 260     r = fread(&ent, sizeof(ent), 1, f);
 261     fclose(f);
 262     if(r){
 263         *auth_lifespan = ent.stamp;
 264         return 0;
 265     }
 266     krb5_clear_error_message (context);
 267     return KRB5_RC_IO_UNKNOWN;
 268 }
 269
 270 const char* KRB5_LIB_FUNCTION
 271 krb5_rc_get_name(krb5_context context,
 272                  krb5_rcache id)
 273 {
 274     return id->name;
 275 }
 276
 277 const char* KRB5_LIB_FUNCTION
 278 krb5_rc_get_type(krb5_context context,
 279                  krb5_rcache id)
 280 {
 281     return "FILE";
 282 }
 283
 284 krb5_error_code KRB5_LIB_FUNCTION
 285 krb5_get_server_rcache(krb5_context context,
 286                        const krb5_data *piece,
 287                        krb5_rcache *id)
 288 {
 289     krb5_rcache rcache;
 290     krb5_error_code ret;
 291
 292     char *tmp = malloc(4 * piece->length + 1);
 293     char *name;
 294
 295     if(tmp == NULL) {
 296         krb5_set_error_message(context, ENOMEM,
 297                                N_("malloc: out of memory", ""));
 298         return ENOMEM;
 299     }
 300     strvisx(tmp, piece->data, piece->length, VIS_WHITE | VIS_OCTAL);
 301 #ifdef HAVE_GETEUID
 302     asprintf(&name, "FILE:rc_%s_%u", tmp, (unsigned)geteuid());
 303 #else
 304     asprintf(&name, "FILE:rc_%s", tmp);
 305 #endif
 306     free(tmp);
 307     if(name == NULL) {
 308         krb5_set_error_message(context, ENOMEM,
 309                                N_("malloc: out of memory", ""));
 310         return ENOMEM;
 311     }
 312
 313     ret = krb5_rc_resolve_full(context, &rcache, name);
 314     free(name);
 315     if(ret)
 316         return ret;
 317     *id = rcache;
 318     return ret;
 319 }