lib/smb2-cmd-write.c

   1 /* -*-  mode:c; tab-width:8; c-basic-offset:8; indent-tabs-mode:nil;  -*- */
   2 /*
   3    Copyright (C) 2016 by Ronnie Sahlberg <ronniesahlberg@gmail.com>
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU Lesser General Public License as published by
   7    the Free Software Foundation; either version 2.1 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public License
  16    along with this program; if not, see <http://www.gnu.org/licenses/>.
  17 */
  18 #ifdef HAVE_CONFIG_H
  19 #include "config.h"
  20 #endif
  21
  22 #ifndef _GNU_SOURCE
  23 #define _GNU_SOURCE
  24 #endif
  25
  26 #ifdef HAVE_STDINT_H
  27 #include <stdint.h>
  28 #endif
  29
  30 #ifdef HAVE_STDLIB_H
  31 #include <stdlib.h>
  32 #endif
  33
  34 #ifdef HAVE_STRING_H
  35 #include <string.h>
  36 #endif
  37
  38 #ifdef STDC_HEADERS
  39 #include <stddef.h>
  40 #endif
  41
  42 #include <errno.h>
  43
  44 #include "smb2.h"
  45 #include "libsmb2.h"
  46 #include "libsmb2-private.h"
  47
  48 static int
  49 smb2_encode_write_request(struct smb2_context *smb2,
  50                           struct smb2_pdu *pdu,
  51                           struct smb2_write_request *req)
  52 {
  53         int len;
  54         uint8_t *buf;
  55         struct smb2_iovec *iov;
  56
  57         len = SMB2_WRITE_REQUEST_SIZE & 0xfffffffe;
  58         buf = calloc(len, sizeof(uint8_t));
  59         if (buf == NULL) {
  60                 smb2_set_error(smb2, "Failed to allocate write buffer");
  61                 return -1;
  62         }
  63
  64         iov = smb2_add_iovector(smb2, &pdu->out, buf, len, free);
  65
  66         if (!smb2->supports_multi_credit && req->length > 64 * 1024) {
  67                 req->length = 64 * 1024;
  68         }
  69         smb2_set_uint16(iov, 0, SMB2_WRITE_REQUEST_SIZE);
  70         smb2_set_uint16(iov, 2, SMB2_HEADER_SIZE + 48);
  71         smb2_set_uint32(iov, 4, req->length);
  72         smb2_set_uint64(iov, 8, req->offset);
  73         memcpy(iov->buf + 16, req->file_id, SMB2_FD_SIZE);
  74         smb2_set_uint32(iov, 32, req->channel);
  75         smb2_set_uint32(iov, 36, req->remaining_bytes);
  76         smb2_set_uint16(iov, 42, req->write_channel_info_length);
  77         smb2_set_uint32(iov, 44, req->flags);
  78
  79         if (req->write_channel_info_length > 0 ||
  80             req->write_channel_info != NULL) {
  81                 smb2_set_error(smb2, "ChannelInfo not yet implemented");
  82                 return -1;
  83         }
  84
  85         return 0;
  86 }
  87
  88 struct smb2_pdu *
  89 smb2_cmd_write_async(struct smb2_context *smb2,
  90                      struct smb2_write_request *req,
  91                      smb2_command_cb cb, void *cb_data)
  92 {
  93         struct smb2_pdu *pdu;
  94
  95         pdu = smb2_allocate_pdu(smb2, SMB2_WRITE, cb, cb_data);
  96         if (pdu == NULL) {
  97                 return NULL;
  98         }
  99
 100         if (smb2_encode_write_request(smb2, pdu, req)) {
 101                 smb2_free_pdu(smb2, pdu);
 102                 return NULL;
 103         }
 104
 105         smb2_add_iovector(smb2, &pdu->out, req->buf,
 106                           req->length, NULL);
 107
 108         if (smb2_pad_to_64bit(smb2, &pdu->out) != 0) {
 109                 smb2_free_pdu(smb2, pdu);
 110                 return NULL;
 111         }
 112
 113         /* Adjust credit charge for large payloads */
 114         if (smb2->supports_multi_credit) {
 115                 pdu->header.credit_charge = (req->length - 1) / 65536 + 1; // 3.1.5.2 of [MS-SMB2]
 116         }
 117
 118         return pdu;
 119 }
 120
 121 int
 122 smb2_process_write_fixed(struct smb2_context *smb2,
 123                          struct smb2_pdu *pdu)
 124 {
 125         struct smb2_write_reply *rep;
 126         struct smb2_iovec *iov = &smb2->in.iov[smb2->in.niov - 1];
 127         uint16_t struct_size;
 128
 129         rep = malloc(sizeof(*rep));
 130         if (rep == NULL) {
 131                 smb2_set_error(smb2, "Failed to allocate write reply");
 132                 return -1;
 133         }
 134         pdu->payload = rep;
 135
 136         smb2_get_uint16(iov, 0, &struct_size);
 137         if (struct_size != SMB2_WRITE_REPLY_SIZE ||
 138             (struct_size & 0xfffe) != iov->len) {
 139                 smb2_set_error(smb2, "Unexpected size of Write "
 140                                "reply. Expected %d, got %d",
 141                                SMB2_WRITE_REPLY_SIZE,
 142                                (int)iov->len);
 143                 return -1;
 144         }
 145
 146         smb2_get_uint32(iov, 4, &rep->count);
 147         smb2_get_uint32(iov, 8, &rep->remaining);
 148
 149         return 0;
 150 }