granicus.if.org Git - strace/blob - file_handle.c

   1 /*
   2  * Copyright (c) 2015 Dmitry V. Levin <ldv@altlinux.org>
   3  * Copyright (c) 2015-2017 The strace developers.
   4  * All rights reserved.
   5  *
   6  * SPDX-License-Identifier: LGPL-2.1-or-later
   7  */
   8
   9 #include "defs.h"
  10
  11 #include "xlat/name_to_handle_at_flags.h"
  12
  13 #ifndef MAX_HANDLE_SZ
  14 # define MAX_HANDLE_SZ 128
  15 #endif
  16
  17 typedef struct {
  18         unsigned int handle_bytes;
  19         int handle_type;
  20 } file_handle_header;
  21
  22 SYS_FUNC(name_to_handle_at)
  23 {
  24         file_handle_header h;
  25         const kernel_ulong_t addr = tcp->u_arg[2];
  26
  27         if (entering(tcp)) {
  28                 /* dirfd */
  29                 print_dirfd(tcp, tcp->u_arg[0]);
  30
  31                 /* pathname */
  32                 printpath(tcp, tcp->u_arg[1]);
  33                 tprints(", ");
  34
  35                 /* handle */
  36                 if (umove_or_printaddr(tcp, addr, &h)) {
  37                         tprints(", ");
  38
  39                         /* mount_id */
  40                         printaddr(tcp->u_arg[3]);
  41                         tprints(", ");
  42
  43                         /* flags */
  44                         printflags(name_to_handle_at_flags, tcp->u_arg[4],
  45                                    "AT_???");
  46
  47                         return RVAL_DECODED;
  48                 }
  49                 tprintf("{handle_bytes=%u", h.handle_bytes);
  50
  51                 set_tcb_priv_ulong(tcp, h.handle_bytes);
  52
  53                 return 0;
  54         } else {
  55                 unsigned int i = get_tcb_priv_ulong(tcp);
  56
  57                 if ((!syserror(tcp) || EOVERFLOW == tcp->u_error)
  58                     && !umove(tcp, addr, &h)) {
  59                         unsigned char f_handle[MAX_HANDLE_SZ];
  60
  61                         if (i != h.handle_bytes)
  62                                 tprintf(" => %u", h.handle_bytes);
  63                         if (!syserror(tcp)) {
  64                                 tprintf(", handle_type=%d", h.handle_type);
  65                                 if (h.handle_bytes > MAX_HANDLE_SZ)
  66                                         h.handle_bytes = MAX_HANDLE_SZ;
  67                                 if (!umoven(tcp, addr + sizeof(h), h.handle_bytes,
  68                                             f_handle)) {
  69                                         tprints(", f_handle=0x");
  70                                         for (i = 0; i < h.handle_bytes; ++i)
  71                                                 tprintf("%02x", f_handle[i]);
  72                                 }
  73                         }
  74                 }
  75                 tprints("}, ");
  76
  77                 /* mount_id */
  78                 printnum_int(tcp, tcp->u_arg[3], "%d");
  79                 tprints(", ");
  80
  81                 /* flags */
  82                 printflags(name_to_handle_at_flags, tcp->u_arg[4], "AT_???");
  83         }
  84         return 0;
  85 }
  86
  87 SYS_FUNC(open_by_handle_at)
  88 {
  89         file_handle_header h;
  90         const kernel_ulong_t addr = tcp->u_arg[1];
  91
  92         /* mount_fd */
  93         printfd(tcp, tcp->u_arg[0]);
  94         tprints(", ");
  95
  96         /* handle */
  97         if (!umove_or_printaddr(tcp, addr, &h)) {
  98                 unsigned char f_handle[MAX_HANDLE_SZ];
  99
 100                 tprintf("{handle_bytes=%u, handle_type=%d",
 101                         h.handle_bytes, h.handle_type);
 102                 if (h.handle_bytes > MAX_HANDLE_SZ)
 103                         h.handle_bytes = MAX_HANDLE_SZ;
 104                 if (!umoven(tcp, addr + sizeof(h), h.handle_bytes, &f_handle)) {
 105                         unsigned int i;
 106
 107                         tprints(", f_handle=0x");
 108                         for (i = 0; i < h.handle_bytes; ++i)
 109                                 tprintf("%02x", f_handle[i]);
 110                 }
 111                 tprints("}");
 112         }
 113         tprints(", ");
 114
 115         /* flags */
 116         tprint_open_modes(tcp->u_arg[2]);
 117
 118         return RVAL_DECODED;
 119 }