source3/modules/onefs_system.c

   1 /*
   2  * Unix SMB/CIFS implementation.
   3  * Support for OneFS system interfaces.
   4  *
   5  * Copyright (C) Tim Prouty, 2008
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "onefs.h"
  22
  23 #include <ifs/ifs_syscalls.h>
  24 #include <isi_acl/isi_acl_util.h>
  25
  26 /*
  27  * Initialize the sm_lock struct before passing it to ifs_createfile.
  28  */
  29 static void smlock_init(connection_struct *conn, struct sm_lock *sml,
  30     bool isexe, uint32_t access_mask, uint32_t share_access,
  31     uint32_t create_options)
  32 {
  33         sml->sm_type.doc = false;
  34         sml->sm_type.isexe = isexe;
  35         sml->sm_type.statonly = is_stat_open(access_mask);
  36         sml->sm_type.access_mask = access_mask;
  37         sml->sm_type.share_access = share_access;
  38
  39         /*
  40          * private_options was previously used for DENY_DOS/DENY_FCB checks in
  41          * the kernel, but are now properly handled by fcb_or_dos_open. In
  42          * these cases, ifs_createfile will return a sharing violation, which
  43          * gives fcb_or_dos_open the chance to open a duplicate file handle.
  44          */
  45         sml->sm_type.private_options = 0;
  46
  47         /* 1 second delay is handled in onefs_open.c by deferring the open */
  48         sml->sm_timeout = timeval_set(0, 0);
  49 }
  50
  51 static void smlock_dump(int debuglevel, const struct sm_lock *sml)
  52 {
  53         if (sml == NULL) {
  54                 DEBUG(debuglevel, ("sml == NULL\n"));
  55                 return;
  56         }
  57
  58         DEBUG(debuglevel,
  59               ("smlock: doc=%s, isexec=%s, statonly=%s, access_mask=0x%x, "
  60                "share_access=0x%x, private_options=0x%x timeout=%d/%d\n",
  61                sml->sm_type.doc ? "True" : "False",
  62                sml->sm_type.isexe ? "True" : "False",
  63                sml->sm_type.statonly ? "True" : "False",
  64                sml->sm_type.access_mask,
  65                sml->sm_type.share_access,
  66                sml->sm_type.private_options,
  67                (int)sml->sm_timeout.tv_sec,
  68                (int)sml->sm_timeout.tv_usec));
  69 }
  70
  71 /**
  72  * External interface to ifs_createfile
  73  */
  74 int onefs_sys_create_file(connection_struct *conn,
  75                           int base_fd,
  76                           const char *path,
  77                           uint32_t access_mask,
  78                           uint32_t open_access_mask,
  79                           uint32_t share_access,
  80                           uint32_t create_options,
  81                           int flags,
  82                           mode_t mode,
  83                           int oplock_request,
  84                           uint64_t id,
  85                           struct security_descriptor *sd,
  86                           uint32_t dos_flags,
  87                           int *granted_oplock)
  88 {
  89         struct sm_lock sml, *psml = NULL;
  90         enum oplock_type onefs_oplock;
  91         enum oplock_type onefs_granted_oplock = OPLOCK_NONE;
  92         struct ifs_security_descriptor ifs_sd = {}, *pifs_sd = NULL;
  93         int secinfo = 0;
  94         int ret_fd = -1;
  95         uint32_t onefs_dos_attributes;
  96
  97         /* Setup security descriptor and get secinfo. */
  98         if (sd != NULL) {
  99                 NTSTATUS status;
 100
 101                 secinfo = (get_sec_info(sd) & IFS_SEC_INFO_KNOWN_MASK);
 102
 103                 status = onefs_samba_sd_to_sd(secinfo, sd, &ifs_sd, SNUM(conn));
 104
 105                 if (!NT_STATUS_IS_OK(status)) {
 106                         DEBUG(1, ("SD initialization failure: %s",
 107                                   nt_errstr(status)));
 108                         errno = EINVAL;
 109                         goto out;
 110                 }
 111
 112                 pifs_sd = &ifs_sd;
 113         }
 114
 115         /* Stripping off private bits will be done for us. */
 116         onefs_oplock = onefs_samba_oplock_to_oplock(oplock_request);
 117
 118         if (!lp_oplocks(SNUM(conn))) {
 119                 SMB_ASSERT(onefs_oplock == OPLOCK_NONE);
 120         }
 121
 122         /* Convert samba dos flags to UF_DOS_* attributes. */
 123         onefs_dos_attributes = dos_attributes_to_stat_dos_flags(dos_flags);
 124
 125         DEBUG(10,("onefs_sys_create_file: base_fd = %d, "
 126                   "open_access_mask = 0x%x, flags = 0x%x, mode = 0x%x, "
 127                   "desired_oplock = %s, id = 0x%x, secinfo = 0x%x, sd = %p, "
 128                   "dos_attributes = 0x%x, path = %s\n", base_fd,
 129                   (unsigned int)open_access_mask,
 130                   (unsigned int)flags,
 131                   (unsigned int)mode,
 132                   onefs_oplock_str(onefs_oplock),
 133                   (unsigned int)id,
 134                   (unsigned int)secinfo, sd,
 135                   (unsigned int)onefs_dos_attributes, path));
 136
 137         /* Initialize smlock struct for files/dirs but not internal opens */
 138         if (!(oplock_request & INTERNAL_OPEN_ONLY)) {
 139                 smlock_init(conn, &sml, is_executable(path), access_mask,
 140                     share_access, create_options);
 141                 psml = &sml;
 142         }
 143
 144         smlock_dump(10, psml);
 145
 146         ret_fd = ifs_createfile(base_fd, path,
 147             (enum ifs_ace_rights)open_access_mask, flags & ~O_ACCMODE, mode,
 148             onefs_oplock, id, psml, secinfo, pifs_sd, onefs_dos_attributes,
 149             &onefs_granted_oplock);
 150
 151         DEBUG(10,("onefs_sys_create_file(%s): ret_fd = %d, "
 152                   "onefs_granted_oplock = %s\n",
 153                   ret_fd < 0 ? strerror(errno) : "success", ret_fd,
 154                   onefs_oplock_str(onefs_granted_oplock)));
 155
 156         if (granted_oplock) {
 157                 *granted_oplock =
 158                     onefs_oplock_to_samba_oplock(onefs_granted_oplock);
 159         }
 160
 161  out:
 162         aclu_free_sd(pifs_sd, false);
 163
 164         return ret_fd;
 165 }
 166
 167 /**
 168  * Only talloc the spill buffer once (reallocing when necessary).
 169  */
 170 static char *get_spill_buffer(size_t new_count)
 171 {
 172         static int cur_count = 0;
 173         static char *spill_buffer = NULL;
 174
 175         /* If a sufficiently sized buffer exists, just return. */
 176         if (new_count <= cur_count) {
 177                 SMB_ASSERT(spill_buffer);
 178                 return spill_buffer;
 179         }
 180
 181         /* Allocate the first time. */
 182         if (cur_count == 0) {
 183                 SMB_ASSERT(!spill_buffer);
 184                 spill_buffer = talloc_array(NULL, char, new_count);
 185                 if (spill_buffer) {
 186                         cur_count = new_count;
 187                 }
 188                 return spill_buffer;
 189         }
 190
 191         /* A buffer exists, but it's not big enough, so realloc. */
 192         SMB_ASSERT(spill_buffer);
 193         spill_buffer = talloc_realloc(NULL, spill_buffer, char, new_count);
 194         if (spill_buffer) {
 195                 cur_count = new_count;
 196         }
 197         return spill_buffer;
 198 }
 199
 200 /**
 201  * recvfile does zero-copy writes given an fd to write to, and a socket with
 202  * some data to write.  If recvfile read more than it was able to write, it
 203  * spills the data into a buffer.  After first reading any additional data
 204  * from the socket into the buffer, the spill buffer is then written with a
 205  * standard pwrite.
 206  */
 207 ssize_t onefs_sys_recvfile(int fromfd, int tofd, SMB_OFF_T offset,
 208                            size_t count)
 209 {
 210         char *spill_buffer = NULL;
 211         bool socket_drained = false;
 212         int ret;
 213         off_t total_rbytes = 0;
 214         off_t total_wbytes = 0;
 215         off_t rbytes;
 216         off_t wbytes;
 217
 218         DEBUG(10,("onefs_recvfile: from = %d, to = %d, offset=%llu, count = "
 219                   "%lu\n", fromfd, tofd, offset, count));
 220
 221         if (count == 0) {
 222                 return 0;
 223         }
 224
 225         /*
 226          * Setup up a buffer for recvfile to spill data that has been read
 227          * from the socket but not written.
 228          */
 229         spill_buffer = get_spill_buffer(count);
 230         if (spill_buffer == NULL) {
 231                 ret = -1;
 232                 goto out;
 233         }
 234
 235         /*
 236          * Keep trying recvfile until:
 237          *  - There is no data left to read on the socket, or
 238          *  - bytes read != bytes written, or
 239          *  - An error is returned that isn't EINTR/EAGAIN
 240          */
 241         do {
 242                 /* Keep track of bytes read/written for recvfile */
 243                 rbytes = 0;
 244                 wbytes = 0;
 245
 246                 DEBUG(10, ("calling recvfile loop, offset + total_wbytes = "
 247                            "%llu, count - total_rbytes = %llu\n",
 248                            offset + total_wbytes, count - total_rbytes));
 249
 250                 ret = recvfile(tofd, fromfd, offset + total_wbytes,
 251                                count - total_wbytes, &rbytes, &wbytes, 0,
 252                                spill_buffer);
 253
 254                 DEBUG(10, ("recvfile ret = %d, errno = %d, rbytes = %llu, "
 255                            "wbytes = %llu\n", ret, ret >= 0 ? 0 : errno,
 256                            rbytes, wbytes));
 257
 258                 /* Update our progress so far */
 259                 total_rbytes += rbytes;
 260                 total_wbytes += wbytes;
 261
 262         } while ((count - total_rbytes) && (rbytes == wbytes) &&
 263                  (ret == -1 && (errno == EINTR || errno == EAGAIN)));
 264
 265         DEBUG(10, ("total_rbytes = %llu, total_wbytes = %llu\n",
 266                    total_rbytes, total_wbytes));
 267
 268         /* Log if recvfile didn't write everything it read. */
 269         if (total_rbytes != total_wbytes) {
 270                 DEBUG(0, ("partial recvfile: total_rbytes=%llu but "
 271                           "total_wbytes=%llu, diff = %llu\n", total_rbytes,
 272                           total_wbytes, total_rbytes - total_wbytes));
 273                 SMB_ASSERT(total_rbytes > total_wbytes);
 274         }
 275
 276         /*
 277          * If there is still data on the socket, read it off.
 278          */
 279         while (total_rbytes < count) {
 280
 281                 DEBUG(0, ("shallow recvfile, reading %llu\n",
 282                           count - total_rbytes));
 283
 284                 /*
 285                  * Read the remaining data into the spill buffer.  recvfile
 286                  * may already have some data in the spill buffer, so start
 287                  * filling the buffer at total_rbytes - total_wbytes.
 288                  */
 289                 ret = sys_read(fromfd,
 290                                spill_buffer + (total_rbytes - total_wbytes),
 291                                count - total_rbytes);
 292
 293                 if (ret == -1) {
 294                         DEBUG(0, ("shallow recvfile read failed: %s\n",
 295                                   strerror(errno)));
 296                         /* Socket is dead, so treat as if it were drained. */
 297                         socket_drained = true;
 298                         goto out;
 299                 }
 300
 301                 /* Data was read so update the rbytes */
 302                 total_rbytes += ret;
 303         }
 304
 305         if (total_rbytes != count) {
 306                 smb_panic("Unread recvfile data still on the socket!");
 307         }
 308
 309         /*
 310          * Now write any spilled data + the extra data read off the socket.
 311          */
 312         while (total_wbytes < count) {
 313
 314                 DEBUG(0, ("partial recvfile, writing %llu\n", count - total_wbytes));
 315
 316                 ret = sys_pwrite(tofd, spill_buffer, count - total_wbytes,
 317                                  offset + total_wbytes);
 318
 319                 if (ret == -1) {
 320                         DEBUG(0, ("partial recvfile write failed: %s\n",
 321                                   strerror(errno)));
 322                         goto out;
 323                 }
 324
 325                 /* Data was written so update the wbytes */
 326                 total_wbytes += ret;
 327         }
 328
 329         /* Success! */
 330         ret = total_wbytes;
 331
 332 out:
 333         /* Make sure we always try to drain the socket. */
 334         if (!socket_drained && count - total_rbytes) {
 335                 int saved_errno = errno;
 336
 337                 if (drain_socket(fromfd, count - total_rbytes) !=
 338                     count - total_rbytes) {
 339                         /* Socket is dead! */
 340                         DEBUG(0, ("drain socket failed: %d\n", errno));
 341                 }
 342                 errno = saved_errno;
 343         }
 344
 345         return ret;
 346 }