diff options
Diffstat (limited to 'source3/modules/vfs_streams_xattr.c')
| -rw-r--r-- | source3/modules/vfs_streams_xattr.c | 685 |
1 files changed, 685 insertions, 0 deletions
diff --git a/source3/modules/vfs_streams_xattr.c b/source3/modules/vfs_streams_xattr.c new file mode 100644 index 0000000000..766e7d10ab --- /dev/null +++ b/source3/modules/vfs_streams_xattr.c @@ -0,0 +1,685 @@ +/* + * Store streams in xattrs + * + * Copyright (C) Volker Lendecke, 2008 + * + * Partly based on James Peach's Darwin module, which is + * + * Copyright (C) James Peach 2006-2007 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#include "includes.h" + +#undef DBGC_CLASS +#define DBGC_CLASS DBGC_VFS + +struct stream_io { + char *base; + char *xattr_name; +}; + +static SMB_INO_T stream_inode(const SMB_STRUCT_STAT *sbuf, const char *sname) +{ + struct MD5Context ctx; + unsigned char hash[16]; + SMB_INO_T result; + char *upper_sname; + + DEBUG(10, ("stream_inode called for %lu/%lu [%s]\n", + (unsigned long)sbuf->st_dev, + (unsigned long)sbuf->st_ino, sname)); + + upper_sname = talloc_strdup_upper(talloc_tos(), sname); + SMB_ASSERT(upper_sname != NULL); + + MD5Init(&ctx); + MD5Update(&ctx, (unsigned char *)&(sbuf->st_dev), + sizeof(sbuf->st_dev)); + MD5Update(&ctx, (unsigned char *)&(sbuf->st_ino), + sizeof(sbuf->st_ino)); + MD5Update(&ctx, (unsigned char *)upper_sname, + talloc_get_size(upper_sname)-1); + MD5Final(hash, &ctx); + + TALLOC_FREE(upper_sname); + + /* Hopefully all the variation is in the lower 4 (or 8) bytes! */ + memcpy(&result, hash, sizeof(result)); + + DEBUG(10, ("stream_inode returns %lu\n", (unsigned long)result)); + + return result; +} + +static ssize_t get_xattr_size(connection_struct *conn, const char *fname, + const char *xattr_name) +{ + NTSTATUS status; + struct ea_struct ea; + ssize_t result; + + status = get_ea_value(talloc_tos(), conn, NULL, fname, + xattr_name, &ea); + + if (!NT_STATUS_IS_OK(status)) { + return -1; + } + + result = ea.value.length-1; + TALLOC_FREE(ea.value.data); + return result; +} + + +static int streams_xattr_fstat(vfs_handle_struct *handle, files_struct *fsp, + SMB_STRUCT_STAT *sbuf) +{ + struct stream_io *io = (struct stream_io *) + VFS_FETCH_FSP_EXTENSION(handle, fsp); + + DEBUG(10, ("streams_xattr_fstat called for %d\n", fsp->fh->fd)); + + if (io == NULL) { + return SMB_VFS_NEXT_FSTAT(handle, fsp, sbuf); + } + + if (SMB_VFS_NEXT_FSTAT(handle, fsp, sbuf) == -1) { + return -1; + } + + sbuf->st_size = get_xattr_size(handle->conn, io->base, io->xattr_name); + if (sbuf->st_size == -1) { + return -1; + } + + DEBUG(10, ("sbuf->st_size = %d\n", (int)sbuf->st_size)); + + sbuf->st_ino = stream_inode(sbuf, io->xattr_name); + sbuf->st_mode &= ~S_IFMT; + sbuf->st_mode |= S_IFREG; + sbuf->st_blocks = sbuf->st_size % STAT_ST_BLOCKSIZE + 1; + + return 0; +} + +static int streams_xattr_stat(vfs_handle_struct *handle, const char *fname, + SMB_STRUCT_STAT *sbuf) +{ + NTSTATUS status; + char *base = NULL, *sname = NULL; + int result = -1; + char *xattr_name; + + if (!is_ntfs_stream_name(fname)) { + return SMB_VFS_NEXT_STAT(handle, fname, sbuf); + } + + status = split_ntfs_stream_name(talloc_tos(), fname, &base, &sname); + if (!NT_STATUS_IS_OK(status)) { + errno = EINVAL; + return -1; + } + + if (SMB_VFS_STAT(handle->conn, base, sbuf) == -1) { + goto fail; + } + + xattr_name = talloc_asprintf(talloc_tos(), "%s%s", + SAMBA_XATTR_DOSSTREAM_PREFIX, sname); + if (xattr_name == NULL) { + errno = ENOMEM; + goto fail; + } + + sbuf->st_size = get_xattr_size(handle->conn, base, xattr_name); + if (sbuf->st_size == -1) { + errno = ENOENT; + goto fail; + } + + sbuf->st_ino = stream_inode(sbuf, xattr_name); + sbuf->st_mode &= ~S_IFMT; + sbuf->st_mode |= S_IFREG; + sbuf->st_blocks = sbuf->st_size % STAT_ST_BLOCKSIZE + 1; + + result = 0; + fail: + TALLOC_FREE(base); + TALLOC_FREE(sname); + return result; +} + +static int streams_xattr_lstat(vfs_handle_struct *handle, const char *fname, + SMB_STRUCT_STAT *sbuf) +{ + NTSTATUS status; + char *base, *sname; + int result = -1; + char *xattr_name; + + if (!is_ntfs_stream_name(fname)) { + return SMB_VFS_NEXT_LSTAT(handle, fname, sbuf); + } + + status = split_ntfs_stream_name(talloc_tos(), fname, &base, &sname); + if (!NT_STATUS_IS_OK(status)) { + errno = EINVAL; + goto fail; + } + + if (SMB_VFS_LSTAT(handle->conn, base, sbuf) == -1) { + goto fail; + } + + xattr_name = talloc_asprintf(talloc_tos(), "%s%s", + SAMBA_XATTR_DOSSTREAM_PREFIX, sname); + if (xattr_name == NULL) { + errno = ENOMEM; + goto fail; + } + + sbuf->st_size = get_xattr_size(handle->conn, base, xattr_name); + if (sbuf->st_size == -1) { + errno = ENOENT; + goto fail; + } + + sbuf->st_ino = stream_inode(sbuf, xattr_name); + sbuf->st_mode &= ~S_IFMT; + sbuf->st_mode |= S_IFREG; + sbuf->st_blocks = sbuf->st_size % STAT_ST_BLOCKSIZE + 1; + + result = 0; + fail: + TALLOC_FREE(base); + TALLOC_FREE(sname); + return result; +} + +static int streams_xattr_open(vfs_handle_struct *handle, const char *fname, + files_struct *fsp, int flags, mode_t mode) +{ + TALLOC_CTX *frame; + NTSTATUS status; + struct stream_io *sio; + char *base, *sname; + struct ea_struct ea; + char *xattr_name; + int baseflags; + int hostfd = -1; + + DEBUG(10, ("streams_xattr_open called for %s\n", fname)); + + if (!is_ntfs_stream_name(fname)) { + return SMB_VFS_NEXT_OPEN(handle, fname, fsp, flags, mode); + } + + frame = talloc_stackframe(); + + status = split_ntfs_stream_name(talloc_tos(), fname, + &base, &sname); + if (!NT_STATUS_IS_OK(status)) { + errno = EINVAL; + goto fail; + } + + xattr_name = talloc_asprintf(talloc_tos(), "%s%s", + SAMBA_XATTR_DOSSTREAM_PREFIX, sname); + if (xattr_name == NULL) { + errno = ENOMEM; + goto fail; + } + + /* + * We use baseflags to turn off nasty side-effects when opening the + * underlying file. + */ + baseflags = flags; + baseflags &= ~O_TRUNC; + baseflags &= ~O_EXCL; + baseflags &= ~O_CREAT; + + hostfd = SMB_VFS_OPEN(handle->conn, base, fsp, baseflags, mode); + + /* It is legit to open a stream on a directory, but the base + * fd has to be read-only. + */ + if ((hostfd == -1) && (errno == EISDIR)) { + baseflags &= ~O_ACCMODE; + baseflags |= O_RDONLY; + hostfd = SMB_VFS_OPEN(handle->conn, fname, fsp, baseflags, + mode); + } + + if (hostfd == -1) { + goto fail; + } + + status = get_ea_value(talloc_tos(), handle->conn, NULL, base, + xattr_name, &ea); + + DEBUG(10, ("get_ea_value returned %s\n", nt_errstr(status))); + + if (!NT_STATUS_IS_OK(status) + && !NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND)) { + /* + * The base file is not there. This is an error even if we got + * O_CREAT, the higher levels should have created the base + * file for us. + */ + DEBUG(10, ("streams_xattr_open: base file %s not around, " + "returning ENOENT\n", base)); + errno = ENOENT; + goto fail; + } + + if (!NT_STATUS_IS_OK(status)) { + /* + * The attribute does not exist + */ + + if (flags & O_CREAT) { + /* + * Darn, xattrs need at least 1 byte + */ + char null = '\0'; + + DEBUG(10, ("creating attribute %s on file %s\n", + xattr_name, base)); + + if (SMB_VFS_SETXATTR( + handle->conn, base, xattr_name, + &null, sizeof(null), + flags & O_EXCL ? XATTR_CREATE : 0) == -1) { + goto fail; + } + } + } + + if (flags & O_TRUNC) { + char null = '\0'; + if (SMB_VFS_SETXATTR( + handle->conn, base, xattr_name, + &null, sizeof(null), + flags & O_EXCL ? XATTR_CREATE : 0) == -1) { + goto fail; + } + } + + sio = (struct stream_io *)VFS_ADD_FSP_EXTENSION(handle, fsp, + struct stream_io); + if (sio == NULL) { + errno = ENOMEM; + goto fail; + } + + sio->xattr_name = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp), + xattr_name); + sio->base = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp), + base); + + if ((sio->xattr_name == NULL) || (sio->base == NULL)) { + errno = ENOMEM; + goto fail; + } + + TALLOC_FREE(frame); + return hostfd; + + fail: + if (hostfd >= 0) { + /* + * BUGBUGBUG -- we would need to call fd_close_posix here, but + * we don't have a full fsp yet + */ + SMB_VFS_CLOSE(fsp, hostfd); + } + + TALLOC_FREE(frame); + return -1; +} + +static int streams_xattr_unlink(vfs_handle_struct *handle, const char *fname) +{ + NTSTATUS status; + char *base = NULL; + char *sname = NULL; + int ret = -1; + char *xattr_name; + + if (!is_ntfs_stream_name(fname)) { + return SMB_VFS_NEXT_UNLINK(handle, fname); + } + + status = split_ntfs_stream_name(talloc_tos(), fname, &base, &sname); + if (!NT_STATUS_IS_OK(status)) { + errno = EINVAL; + goto fail; + } + + xattr_name = talloc_asprintf(talloc_tos(), "%s%s", + SAMBA_XATTR_DOSSTREAM_PREFIX, sname); + if (xattr_name == NULL) { + errno = ENOMEM; + goto fail; + } + + ret = SMB_VFS_REMOVEXATTR(handle->conn, base, xattr_name); + + if ((ret == -1) && (errno == ENOATTR)) { + errno = ENOENT; + goto fail; + } + + ret = 0; + + fail: + TALLOC_FREE(base); + TALLOC_FREE(sname); + return ret; +} + +static NTSTATUS walk_xattr_streams(connection_struct *conn, files_struct *fsp, + const char *fname, + bool (*fn)(struct ea_struct *ea, + void *private_data), + void *private_data) +{ + NTSTATUS status; + char **names; + size_t i, num_names; + size_t prefix_len = strlen(SAMBA_XATTR_DOSSTREAM_PREFIX); + + status = get_ea_names_from_file(talloc_tos(), conn, fsp, fname, + &names, &num_names); + if (!NT_STATUS_IS_OK(status)) { + return status; + } + + for (i=0; i<num_names; i++) { + struct ea_struct ea; + + if (strncmp(names[i], SAMBA_XATTR_DOSSTREAM_PREFIX, + prefix_len) != 0) { + continue; + } + + status = get_ea_value(names, conn, fsp, fname, names[i], &ea); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(10, ("Could not get ea %s for file %s: %s\n", + names[i], fname, nt_errstr(status))); + continue; + } + + ea.name = talloc_asprintf(ea.value.data, ":%s", + names[i] + prefix_len); + if (ea.name == NULL) { + DEBUG(0, ("talloc failed\n")); + continue; + } + + if (!fn(&ea, private_data)) { + TALLOC_FREE(ea.value.data); + return NT_STATUS_OK; + } + + TALLOC_FREE(ea.value.data); + } + + TALLOC_FREE(names); + return NT_STATUS_OK; +} + +static bool add_one_stream(TALLOC_CTX *mem_ctx, unsigned int *num_streams, + struct stream_struct **streams, + const char *name, SMB_OFF_T size, + SMB_OFF_T alloc_size) +{ + struct stream_struct *tmp; + + tmp = TALLOC_REALLOC_ARRAY(mem_ctx, *streams, struct stream_struct, + (*num_streams)+1); + if (tmp == NULL) { + return false; + } + + tmp[*num_streams].name = talloc_strdup(tmp, name); + if (tmp[*num_streams].name == NULL) { + return false; + } + + tmp[*num_streams].size = size; + tmp[*num_streams].alloc_size = alloc_size; + + *streams = tmp; + *num_streams += 1; + return true; +} + +struct streaminfo_state { + TALLOC_CTX *mem_ctx; + vfs_handle_struct *handle; + unsigned int num_streams; + struct stream_struct *streams; + NTSTATUS status; +}; + +static bool collect_one_stream(struct ea_struct *ea, void *private_data) +{ + struct streaminfo_state *state = + (struct streaminfo_state *)private_data; + + if (!add_one_stream(state->mem_ctx, + &state->num_streams, &state->streams, + ea->name, ea->value.length-1, + smb_roundup(state->handle->conn, + ea->value.length-1))) { + state->status = NT_STATUS_NO_MEMORY; + return false; + } + + return true; +} + +static NTSTATUS streams_xattr_streaminfo(vfs_handle_struct *handle, + struct files_struct *fsp, + const char *fname, + TALLOC_CTX *mem_ctx, + unsigned int *pnum_streams, + struct stream_struct **pstreams) +{ + SMB_STRUCT_STAT sbuf; + int ret; + NTSTATUS status; + struct streaminfo_state state; + + if ((fsp != NULL) && (fsp->fh->fd != -1)) { + if (is_ntfs_stream_name(fsp->fsp_name)) { + return NT_STATUS_INVALID_PARAMETER; + } + ret = SMB_VFS_FSTAT(fsp, &sbuf); + } + else { + if (is_ntfs_stream_name(fname)) { + return NT_STATUS_INVALID_PARAMETER; + } + ret = SMB_VFS_STAT(handle->conn, fname, &sbuf); + } + + if (ret == -1) { + return map_nt_error_from_unix(errno); + } + + state.streams = NULL; + state.num_streams = 0; + + if (!S_ISDIR(sbuf.st_mode)) { + if (!add_one_stream(mem_ctx, + &state.num_streams, &state.streams, + "::$DATA", sbuf.st_size, + get_allocation_size(handle->conn, fsp, + &sbuf))) { + return NT_STATUS_NO_MEMORY; + } + } + + state.mem_ctx = mem_ctx; + state.handle = handle; + state.status = NT_STATUS_OK; + + status = walk_xattr_streams(handle->conn, fsp, fname, + collect_one_stream, &state); + + if (!NT_STATUS_IS_OK(status)) { + TALLOC_FREE(state.streams); + return status; + } + + if (!NT_STATUS_IS_OK(state.status)) { + TALLOC_FREE(state.streams); + return state.status; + } + + *pnum_streams = state.num_streams; + *pstreams = state.streams; + return NT_STATUS_OK; +} + +static uint32_t streams_xattr_fs_capabilities(struct vfs_handle_struct *handle) +{ + return SMB_VFS_NEXT_FS_CAPABILITIES(handle) | FILE_NAMED_STREAMS; +} + +static ssize_t streams_xattr_pwrite(vfs_handle_struct *handle, + files_struct *fsp, const void *data, + size_t n, SMB_OFF_T offset) +{ + struct stream_io *sio = + (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp); + struct ea_struct ea; + NTSTATUS status; + int ret; + + DEBUG(10, ("streams_xattr_pwrite called for %d bytes\n", (int)n)); + + if (sio == NULL) { + return SMB_VFS_NEXT_PWRITE(handle, fsp, data, n, offset); + } + + status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp, + sio->base, sio->xattr_name, &ea); + if (!NT_STATUS_IS_OK(status)) { + return -1; + } + + if ((offset + n) > ea.value.length-1) { + uint8 *tmp; + + tmp = TALLOC_REALLOC_ARRAY(talloc_tos(), ea.value.data, uint8, + offset + n + 1); + + if (tmp == NULL) { + TALLOC_FREE(ea.value.data); + errno = ENOMEM; + return -1; + } + ea.value.data = tmp; + ea.value.length = offset + n + 1; + ea.value.data[offset+n] = 0; + } + + memcpy(ea.value.data + offset, data, n); + + ret = SMB_VFS_SETXATTR(fsp->conn, fsp->base_fsp->fsp_name, + sio->xattr_name, + ea.value.data, ea.value.length, 0); + + TALLOC_FREE(ea.value.data); + + if (ret == -1) { + return -1; + } + + return n; +} + +static ssize_t streams_xattr_pread(vfs_handle_struct *handle, + files_struct *fsp, void *data, + size_t n, SMB_OFF_T offset) +{ + struct stream_io *sio = + (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp); + struct ea_struct ea; + NTSTATUS status; + size_t length, overlap; + + if (sio == NULL) { + return SMB_VFS_NEXT_PREAD(handle, fsp, data, n, offset); + } + + status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp, + sio->base, sio->xattr_name, &ea); + if (!NT_STATUS_IS_OK(status)) { + return -1; + } + + length = ea.value.length-1; + + /* Attempt to read past EOF. */ + if (length <= offset) { + errno = EINVAL; + return -1; + } + + overlap = (offset + n) > length ? (length - offset) : n; + memcpy(data, ea.value.data + offset, overlap); + + TALLOC_FREE(ea.value.data); + return overlap; +} + +/* VFS operations structure */ + +static vfs_op_tuple streams_xattr_ops[] = { + {SMB_VFS_OP(streams_xattr_fs_capabilities), SMB_VFS_OP_FS_CAPABILITIES, + SMB_VFS_LAYER_TRANSPARENT}, + {SMB_VFS_OP(streams_xattr_open), SMB_VFS_OP_OPEN, + SMB_VFS_LAYER_TRANSPARENT}, + {SMB_VFS_OP(streams_xattr_stat), SMB_VFS_OP_STAT, + SMB_VFS_LAYER_TRANSPARENT}, + {SMB_VFS_OP(streams_xattr_fstat), SMB_VFS_OP_FSTAT, + SMB_VFS_LAYER_TRANSPARENT}, + {SMB_VFS_OP(streams_xattr_lstat), SMB_VFS_OP_LSTAT, + SMB_VFS_LAYER_TRANSPARENT}, + {SMB_VFS_OP(streams_xattr_pread), SMB_VFS_OP_PREAD, + SMB_VFS_LAYER_TRANSPARENT}, + {SMB_VFS_OP(streams_xattr_pwrite), SMB_VFS_OP_PWRITE, + SMB_VFS_LAYER_TRANSPARENT}, + {SMB_VFS_OP(streams_xattr_lstat), SMB_VFS_OP_LSTAT, + SMB_VFS_LAYER_TRANSPARENT}, + {SMB_VFS_OP(streams_xattr_unlink), SMB_VFS_OP_UNLINK, + SMB_VFS_LAYER_TRANSPARENT}, + {SMB_VFS_OP(streams_xattr_streaminfo), SMB_VFS_OP_STREAMINFO, + SMB_VFS_LAYER_OPAQUE}, + {SMB_VFS_OP(NULL), SMB_VFS_OP_NOOP, SMB_VFS_LAYER_NOOP} +}; + +NTSTATUS vfs_streams_xattr_init(void); +NTSTATUS vfs_streams_xattr_init(void) +{ + return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "streams_xattr", + streams_xattr_ops); +} |