src/afs/LINUX/osi_cred.c

   1 /*
   2  * Copyright 2000, International Business Machines Corporation and others.
   3  * All Rights Reserved.
   4  *
   5  * This software has been released under the terms of the IBM Public
   6  * License.  For details, see the LICENSE file in the top-level source
   7  * directory or online at http://www.openafs.org/dl/license10.html
   8  */
   9
  10 /*
  11  * osi_cred.c - Linux cred handling routines.
  12  *
  13  */
  14 #include <afsconfig.h>
  15 #include "afs/param.h"
  16
  17
  18 #include "afs/sysincludes.h"
  19 #include "afsincludes.h"
  20
  21 cred_t *
  22 crget(void)
  23 {
  24     cred_t *tmp;
  25
  26 #if !defined(GFP_NOFS)
  27 #define GFP_NOFS GFP_KERNEL
  28 #endif
  29     tmp = kmalloc(sizeof(cred_t), GFP_NOFS);
  30     if (!tmp)
  31         osi_Panic("crget: No more memory for creds!\n");
  32
  33     tmp->cr_ref = 1;
  34     return tmp;
  35 }
  36
  37 void
  38 crfree(cred_t * cr)
  39 {
  40     if (cr->cr_ref > 1) {
  41         cr->cr_ref--;
  42         return;
  43     }
  44
  45     put_group_info(cr->cr_group_info);
  46
  47     kfree(cr);
  48 }
  49
  50
  51 /* Return a duplicate of the cred. */
  52 cred_t *
  53 crdup(cred_t * cr)
  54 {
  55     cred_t *tmp = crget();
  56
  57     tmp->cr_uid = cr->cr_uid;
  58     tmp->cr_ruid = cr->cr_ruid;
  59     tmp->cr_gid = cr->cr_gid;
  60     tmp->cr_rgid = cr->cr_rgid;
  61
  62     get_group_info(cr->cr_group_info);
  63     tmp->cr_group_info = cr->cr_group_info;
  64
  65     return tmp;
  66 }
  67
  68 cred_t *
  69 crref(void)
  70 {
  71     cred_t *cr = crget();
  72
  73     cr->cr_uid = current_fsuid();
  74     cr->cr_ruid = current_uid();
  75     cr->cr_gid = current_fsgid();
  76     cr->cr_rgid = current_gid();
  77
  78     task_lock(current);
  79     get_group_info(current_group_info());
  80     cr->cr_group_info = current_group_info();
  81     task_unlock(current);
  82
  83     return cr;
  84 }
  85
  86 /* Set the cred info into the current task */
  87 void
  88 crset(cred_t * cr)
  89 {
  90     struct group_info *old_info;
  91 #if defined(STRUCT_TASK_HAS_CRED)
  92     struct cred *new_creds;
  93
  94     /* If our current task doesn't have identical real and effective
  95      * credentials, commit_cred won't let us change them, so we just
  96      * bail here.
  97      */
  98     if (current->cred != current->real_cred)
  99         return;
 100     new_creds = prepare_creds();
 101     new_creds->fsuid = cr->cr_uid;
 102     new_creds->uid = cr->cr_ruid;
 103     new_creds->fsgid = cr->cr_gid;
 104     new_creds->gid = cr->cr_rgid;
 105 #else
 106     current->fsuid = cr->cr_uid;
 107     current->uid = cr->cr_ruid;
 108     current->fsgid = cr->cr_gid;
 109     current->gid = cr->cr_rgid;
 110 #endif
 111
 112     /* using set_current_groups() will sort the groups */
 113     get_group_info(cr->cr_group_info);
 114
 115     task_lock(current);
 116 #if defined(STRUCT_TASK_HAS_CRED)
 117     old_info = current->cred->group_info;
 118     new_creds->group_info = cr->cr_group_info;
 119     commit_creds(new_creds);
 120 #else
 121     old_info = current->group_info;
 122     current->group_info = cr->cr_group_info;
 123 #endif
 124     task_unlock(current);
 125
 126     put_group_info(old_info);
 127 }