source3/libsmb/smb2cli_read.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    smb2 lib
   4    Copyright (C) Volker Lendecke 2011
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "client.h"
  22 #include "async_smb.h"
  23 #include "../libcli/smb/smbXcli_base.h"
  24 #include "smb2cli.h"
  25 #include "libsmb/proto.h"
  26 #include "lib/util/tevent_ntstatus.h"
  27
  28 struct smb2cli_read_state {
  29         uint8_t fixed[48];
  30         uint8_t dyn_pad[1];
  31         struct iovec *recv_iov;
  32         uint8_t *data;
  33         uint32_t data_length;
  34 };
  35
  36 static void smb2cli_read_done(struct tevent_req *subreq);
  37
  38 struct tevent_req *smb2cli_read_send(TALLOC_CTX *mem_ctx,
  39                                      struct tevent_context *ev,
  40                                      struct smbXcli_conn *conn,
  41                                      uint32_t timeout_msec,
  42                                      struct smbXcli_session *session,
  43                                      uint32_t tcon_id,
  44                                      uint32_t length,
  45                                      uint64_t offset,
  46                                      uint64_t fid_persistent,
  47                                      uint64_t fid_volatile,
  48                                      uint64_t minimum_count,
  49                                      uint64_t remaining_bytes)
  50 {
  51         struct tevent_req *req, *subreq;
  52         struct smb2cli_read_state *state;
  53         uint8_t *fixed;
  54
  55         req = tevent_req_create(mem_ctx, &state,
  56                                 struct smb2cli_read_state);
  57         if (req == NULL) {
  58                 return NULL;
  59         }
  60
  61         fixed = state->fixed;
  62
  63         SSVAL(fixed, 0, 49);
  64         SIVAL(fixed, 4, length);
  65         SBVAL(fixed, 8, offset);
  66         SBVAL(fixed, 16, fid_persistent);
  67         SBVAL(fixed, 24, fid_volatile);
  68         SBVAL(fixed, 32, minimum_count);
  69         SBVAL(fixed, 40, remaining_bytes);
  70
  71         subreq = smb2cli_req_send(state, ev, conn, SMB2_OP_READ,
  72                                   0, 0, /* flags */
  73                                   timeout_msec,
  74                                   0xFEFF, /* pid */
  75                                   tcon_id,
  76                                   session,
  77                                   state->fixed, sizeof(state->fixed),
  78                                   state->dyn_pad, sizeof(state->dyn_pad));
  79         if (tevent_req_nomem(subreq, req)) {
  80                 return tevent_req_post(req, ev);
  81         }
  82         tevent_req_set_callback(subreq, smb2cli_read_done, req);
  83         return req;
  84 }
  85
  86 static void smb2cli_read_done(struct tevent_req *subreq)
  87 {
  88         struct tevent_req *req = tevent_req_callback_data(
  89                 subreq, struct tevent_req);
  90         struct smb2cli_read_state *state =
  91                 tevent_req_data(req,
  92                 struct smb2cli_read_state);
  93         NTSTATUS status;
  94         struct iovec *iov;
  95         uint8_t data_offset;
  96         static const struct smb2cli_req_expected_response expected[] = {
  97         {
  98                 .status = STATUS_BUFFER_OVERFLOW,
  99                 .body_size = 0x11
 100         },
 101         {
 102                 .status = NT_STATUS_OK,
 103                 .body_size = 0x11
 104         }
 105         };
 106
 107         status = smb2cli_req_recv(subreq, state, &iov,
 108                                   expected, ARRAY_SIZE(expected));
 109         if (tevent_req_nterror(req, status)) {
 110                 return;
 111         }
 112
 113         data_offset = CVAL(iov[1].iov_base, 2);
 114         state->data_length = IVAL(iov[1].iov_base, 4);
 115
 116         if ((data_offset != SMB2_HDR_BODY + 16) ||
 117             (state->data_length > iov[2].iov_len)) {
 118                 tevent_req_nterror(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
 119                 return;
 120         }
 121
 122         state->recv_iov = iov;
 123         state->data = (uint8_t *)iov[2].iov_base;
 124         tevent_req_done(req);
 125 }
 126
 127 NTSTATUS smb2cli_read_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
 128                            uint8_t **data, uint32_t *data_length)
 129 {
 130         struct smb2cli_read_state *state =
 131                 tevent_req_data(req,
 132                 struct smb2cli_read_state);
 133         NTSTATUS status;
 134
 135         if (tevent_req_is_nterror(req, &status)) {
 136                 return status;
 137         }
 138         talloc_steal(mem_ctx, state->recv_iov);
 139         *data_length = state->data_length;
 140         *data = state->data;
 141         return NT_STATUS_OK;
 142 }
 143
 144 NTSTATUS smb2cli_read(struct smbXcli_conn *conn,
 145                       uint32_t timeout_msec,
 146                       struct smbXcli_session *session,
 147                       uint32_t tcon_id,
 148                       uint32_t length,
 149                       uint64_t offset,
 150                       uint64_t fid_persistent,
 151                       uint64_t fid_volatile,
 152                       uint64_t minimum_count,
 153                       uint64_t remaining_bytes,
 154                       TALLOC_CTX *mem_ctx,
 155                       uint8_t **data,
 156                       uint32_t *data_length)
 157 {
 158         TALLOC_CTX *frame = talloc_stackframe();
 159         struct event_context *ev;
 160         struct tevent_req *req;
 161         NTSTATUS status = NT_STATUS_NO_MEMORY;
 162
 163         if (smbXcli_conn_has_async_calls(conn)) {
 164                 /*
 165                  * Can't use sync call while an async call is in flight
 166                  */
 167                 status = NT_STATUS_INVALID_PARAMETER;
 168                 goto fail;
 169         }
 170         ev = event_context_init(frame);
 171         if (ev == NULL) {
 172                 goto fail;
 173         }
 174         req = smb2cli_read_send(frame, ev,
 175                                 conn, timeout_msec, session, tcon_id,
 176                                 length, offset,
 177                                 fid_persistent, fid_volatile,
 178                                 minimum_count, remaining_bytes);
 179         if (req == NULL) {
 180                 goto fail;
 181         }
 182         if (!tevent_req_poll_ntstatus(req, ev, &status)) {
 183                 goto fail;
 184         }
 185         status = smb2cli_read_recv(req, mem_ctx, data, data_length);
 186  fail:
 187         TALLOC_FREE(frame);
 188         return status;
 189 }