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

   1 /*
   2  * Copyright (c) 2015 Dmitry V. Levin <ldv@altlinux.org>
   3  * Copyright (c) 2015-2019 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                 tprints(", ");
  31
  32                 /* pathname */
  33                 printpath(tcp, tcp->u_arg[1]);
  34                 tprints(", ");
  35
  36                 /* handle */
  37                 if (umove_or_printaddr(tcp, addr, &h)) {
  38                         tprints(", ");
  39
  40                         /* mount_id */
  41                         printaddr(tcp->u_arg[3]);
  42                         tprints(", ");
  43
  44                         /* flags */
  45                         printflags(name_to_handle_at_flags, tcp->u_arg[4],
  46                                    "AT_???");
  47
  48                         return RVAL_DECODED;
  49                 }
  50                 tprintf("{handle_bytes=%u", h.handle_bytes);
  51
  52                 set_tcb_priv_ulong(tcp, h.handle_bytes);
  53
  54                 return 0;
  55         } else {
  56                 unsigned int i = get_tcb_priv_ulong(tcp);
  57
  58                 if ((!syserror(tcp) || EOVERFLOW == tcp->u_error)
  59                     && !umove(tcp, addr, &h)) {
  60                         unsigned char f_handle[MAX_HANDLE_SZ];
  61
  62                         if (i != h.handle_bytes)
  63                                 tprintf(" => %u", h.handle_bytes);
  64                         if (!syserror(tcp)) {
  65                                 tprintf(", handle_type=%d", h.handle_type);
  66                                 if (h.handle_bytes > MAX_HANDLE_SZ)
  67                                         h.handle_bytes = MAX_HANDLE_SZ;
  68                                 if (!umoven(tcp, addr + sizeof(h), h.handle_bytes,
  69                                             f_handle)) {
  70                                         tprints(", f_handle=0x");
  71                                         for (i = 0; i < h.handle_bytes; ++i)
  72                                                 tprintf("%02x", f_handle[i]);
  73                                 }
  74                         }
  75                 }
  76                 tprints("}, ");
  77
  78                 /* mount_id */
  79                 printnum_int(tcp, tcp->u_arg[3], "%d");
  80                 tprints(", ");
  81
  82                 /* flags */
  83                 printflags(name_to_handle_at_flags, tcp->u_arg[4], "AT_???");
  84         }
  85         return 0;
  86 }
  87
  88 SYS_FUNC(open_by_handle_at)
  89 {
  90         file_handle_header h;
  91         const kernel_ulong_t addr = tcp->u_arg[1];
  92
  93         /* mount_fd */
  94         printfd(tcp, tcp->u_arg[0]);
  95         tprints(", ");
  96
  97         /* handle */
  98         if (!umove_or_printaddr(tcp, addr, &h)) {
  99                 unsigned char f_handle[MAX_HANDLE_SZ];
 100
 101                 tprintf("{handle_bytes=%u, handle_type=%d",
 102                         h.handle_bytes, h.handle_type);
 103                 if (h.handle_bytes > MAX_HANDLE_SZ)
 104                         h.handle_bytes = MAX_HANDLE_SZ;
 105                 if (!umoven(tcp, addr + sizeof(h), h.handle_bytes, &f_handle)) {
 106                         unsigned int i;
 107
 108                         tprints(", f_handle=0x");
 109                         for (i = 0; i < h.handle_bytes; ++i)
 110                                 tprintf("%02x", f_handle[i]);
 111                 }
 112                 tprints("}");
 113         }
 114         tprints(", ");
 115
 116         /* flags */
 117         tprint_open_modes(tcp->u_arg[2]);
 118
 119         return RVAL_DECODED;
 120 }