kernel/syscall/ucredsys.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #include <sys/param.h>
  27 #include <sys/types.h>
  28 #include <sys/ucred.h>
  29 #include <sys/file.h>
  30 #include <sys/errno.h>
  31 #include <sys/systm.h>
  32 #include <sys/stream.h>
  33 #include <sys/strsun.h>
  34 #include <sys/stropts.h>
  35 #include <sys/vfs.h>
  36 #include <sys/vnode.h>
  37 #include <sys/cmn_err.h>
  38 #include <sys/socket.h>
  39 #include <sys/strsubr.h>
  40
  41 /*
  42  * Getpeerucred system call implementation.
  43  */
  44 static int
  45 getpeerucred(int fd, void *buf)
  46 {
  47         file_t *fp;
  48         struct ucred_s *uc;
  49         vnode_t *vp;
  50         k_peercred_t kpc;
  51         int err;
  52         int32_t rval;
  53
  54         kpc.pc_cr = NULL;
  55         kpc.pc_cpid = -1;
  56
  57         if ((fp = getf(fd)) == NULL)
  58                 return (set_errno(EBADF));
  59
  60         vp = fp->f_vnode;
  61
  62         switch (vp->v_type) {
  63         case VFIFO:
  64         case VSOCK:
  65                 err = fop_ioctl(vp, _I_GETPEERCRED, (intptr_t)&kpc,
  66                     FKIOCTL, CRED(), &rval, NULL);
  67                 break;
  68         case VCHR: {
  69                 struct strioctl strioc;
  70
  71                 if (vp->v_stream == NULL) {
  72                         err = ENOTSUP;
  73                         break;
  74                 }
  75                 strioc.ic_cmd = _I_GETPEERCRED;
  76                 strioc.ic_timout = INFTIM;
  77                 strioc.ic_len = (int)sizeof (k_peercred_t);
  78                 strioc.ic_dp = (char *)&kpc;
  79
  80                 err = strdoioctl(vp->v_stream, &strioc, FNATIVE|FKIOCTL,
  81                     STR_NOSIG|K_TO_K, CRED(), &rval);
  82
  83                 /*
  84                  * Map all unexpected error codes to ENOTSUP.
  85                  */
  86                 switch (err) {
  87                 case 0:
  88                 case ENOTSUP:
  89                 case ENOTCONN:
  90                 case ENOMEM:
  91                         break;
  92                 default:
  93                         err = ENOTSUP;
  94                         break;
  95                 }
  96                 break;
  97         }
  98         default:
  99                 err = ENOTSUP;
 100                 break;
 101         }
 102         releasef(fd);
 103
 104         /*
 105          * If someone gave us a credential, err will be 0.
 106          */
 107         if (kpc.pc_cr != NULL) {
 108                 ASSERT(err == 0);
 109
 110                 uc = cred2ucred(kpc.pc_cr, kpc.pc_cpid, NULL, CRED());
 111
 112                 crfree(kpc.pc_cr);
 113
 114                 err = copyout(uc, buf, uc->uc_size);
 115
 116                 kmem_free(uc, uc->uc_size);
 117
 118                 if (err != 0)
 119                         return (set_errno(EFAULT));
 120
 121                 return (0);
 122         }
 123         return (set_errno(err));
 124 }
 125
 126 static int
 127 ucred_get(pid_t pid, void *ubuf)
 128 {
 129         proc_t *p;
 130         cred_t *pcr;
 131         int err;
 132         struct ucred_s *uc;
 133
 134         if (pid == P_MYID || pid == curproc->p_pid) {
 135                 pcr = CRED();
 136                 crhold(pcr);
 137                 pid = curproc->p_pid;
 138         } else {
 139                 cred_t  *updcred = NULL;
 140
 141                 if (pid < 0)
 142                         return (set_errno(EINVAL));
 143
 144                 mutex_enter(&pidlock);
 145                 p = prfind(pid);
 146
 147                 if (p == NULL) {
 148                         mutex_exit(&pidlock);
 149                         if (updcred != NULL)
 150                                 crfree(updcred);
 151                         return (set_errno(ESRCH));
 152                 }
 153
 154                 err = priv_proc_cred_perm(CRED(), p, &pcr, VREAD);
 155                 mutex_exit(&pidlock);
 156
 157                 if (err != 0)
 158                         return (set_errno(err));
 159         }
 160
 161         uc = cred2ucred(pcr, pid, NULL, CRED());
 162
 163         crfree(pcr);
 164
 165         err = copyout(uc, ubuf, uc->uc_size);
 166
 167         kmem_free(uc, uc->uc_size);
 168
 169         if (err)
 170                 return (set_errno(EFAULT));
 171
 172         return (0);
 173 }
 174
 175 int
 176 ucredsys(int code, int obj, void *buf)
 177 {
 178         switch (code) {
 179         case UCREDSYS_UCREDGET:
 180                 return (ucred_get((pid_t)obj, buf));
 181         case UCREDSYS_GETPEERUCRED:
 182                 return (getpeerucred(obj, buf));
 183         default:
 184                 return (set_errno(EINVAL));
 185         }
 186 }
 187
 188 #ifdef _SYSCALL32_IMPL
 189 int
 190 ucredsys32(int arg1, int arg2, caddr32_t arg3)
 191 {
 192         return (ucredsys(arg1, arg2, (void *)(uintptr_t)arg3));
 193 }
 194 #endif