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-rw-r--r--source4/ntvfs/posix/pvfs_streams.c556
1 files changed, 556 insertions, 0 deletions
diff --git a/source4/ntvfs/posix/pvfs_streams.c b/source4/ntvfs/posix/pvfs_streams.c
new file mode 100644
index 0000000..9210237
--- /dev/null
+++ b/source4/ntvfs/posix/pvfs_streams.c
@@ -0,0 +1,556 @@
+/*
+ Unix SMB/CIFS implementation.
+
+ POSIX NTVFS backend - alternate data streams
+
+ Copyright (C) Andrew Tridgell 2004
+
+ 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"
+#include "vfs_posix.h"
+#include "librpc/gen_ndr/xattr.h"
+
+/*
+ normalise a stream name, removing a :$DATA suffix if there is one
+ Note: this returns the existing pointer to the name if the name does
+ not need normalising
+ */
+static const char *stream_name_normalise(TALLOC_CTX *ctx, const char *name)
+{
+ const char *c = strchr_m(name, ':');
+ if (c == NULL || strcasecmp_m(c, ":$DATA") != 0) {
+ return name;
+ }
+ return talloc_strndup(ctx, name, c-name);
+}
+
+/*
+ compare two stream names, taking account of the default $DATA extension
+ */
+static int stream_name_cmp(const char *name1, const char *name2)
+{
+ const char *c1, *c2;
+ int l1, l2, ret;
+ c1 = strchr_m(name1, ':');
+ c2 = strchr_m(name2, ':');
+
+ /* check the first part is the same */
+ l1 = c1?(c1 - name1):strlen(name1);
+ l2 = c2?(c2 - name2):strlen(name2);
+ if (l1 != l2) {
+ return l1 - l2;
+ }
+ ret = strncasecmp_m(name1, name2, l1);
+ if (ret != 0) {
+ return ret;
+ }
+
+ /* the first parts are the same, check the suffix */
+ if (c1 && c2) {
+ return strcasecmp_m(c1, c2);
+ }
+
+ if (c1) {
+ return strcasecmp_m(c1, ":$DATA");
+ }
+ if (c2) {
+ return strcasecmp_m(c2, ":$DATA");
+ }
+
+ /* neither names have a suffix */
+ return 0;
+}
+
+
+/*
+ return the list of file streams for RAW_FILEINFO_STREAM_INFORMATION
+*/
+NTSTATUS pvfs_stream_information(struct pvfs_state *pvfs,
+ TALLOC_CTX *mem_ctx,
+ struct pvfs_filename *name, int fd,
+ struct stream_information *info)
+{
+ struct xattr_DosStreams *streams;
+ int i;
+ NTSTATUS status;
+
+ /* directories don't have streams */
+ if (name->dos.attrib & FILE_ATTRIBUTE_DIRECTORY) {
+ info->num_streams = 0;
+ info->streams = NULL;
+ return NT_STATUS_OK;
+ }
+
+ streams = talloc(mem_ctx, struct xattr_DosStreams);
+ if (streams == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ status = pvfs_streams_load(pvfs, name, fd, streams);
+ if (!NT_STATUS_IS_OK(status)) {
+ ZERO_STRUCTP(streams);
+ }
+
+ info->num_streams = streams->num_streams+1;
+ info->streams = talloc_array(mem_ctx, struct stream_struct, info->num_streams);
+ if (!info->streams) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ info->streams[0].size = name->st.st_size;
+ info->streams[0].alloc_size = name->dos.alloc_size;
+ info->streams[0].stream_name.s = talloc_strdup(info->streams, "::$DATA");
+
+ for (i=0;i<streams->num_streams;i++) {
+ info->streams[i+1].size = streams->streams[i].size;
+ info->streams[i+1].alloc_size = streams->streams[i].alloc_size;
+ if (strchr(streams->streams[i].name, ':') == NULL) {
+ info->streams[i+1].stream_name.s = talloc_asprintf(streams->streams,
+ ":%s:$DATA",
+ streams->streams[i].name);
+ } else {
+ info->streams[i+1].stream_name.s = talloc_strdup(streams->streams,
+ streams->streams[i].name);
+ }
+ }
+
+ return NT_STATUS_OK;
+}
+
+
+/*
+ fill in the stream information for a name
+*/
+NTSTATUS pvfs_stream_info(struct pvfs_state *pvfs, struct pvfs_filename *name, int fd)
+{
+ struct xattr_DosStreams *streams;
+ int i;
+ NTSTATUS status;
+
+ /* the NULL stream always exists */
+ if (name->stream_name == NULL) {
+ name->stream_exists = true;
+ return NT_STATUS_OK;
+ }
+
+ streams = talloc(name, struct xattr_DosStreams);
+ if (streams == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ status = pvfs_streams_load(pvfs, name, fd, streams);
+ if (!NT_STATUS_IS_OK(status)) {
+ talloc_free(streams);
+ return status;
+ }
+
+ for (i=0;i<streams->num_streams;i++) {
+ struct xattr_DosStream *s = &streams->streams[i];
+ if (stream_name_cmp(s->name, name->stream_name) == 0) {
+ name->dos.alloc_size = pvfs_round_alloc_size(pvfs, s->alloc_size);
+ name->st.st_size = s->size;
+ name->stream_exists = true;
+ talloc_free(streams);
+ return NT_STATUS_OK;
+ }
+ }
+
+ talloc_free(streams);
+
+ name->dos.alloc_size = 0;
+ name->st.st_size = 0;
+ name->stream_exists = false;
+
+ return NT_STATUS_OK;
+}
+
+
+/*
+ update size information for a stream
+*/
+static NTSTATUS pvfs_stream_update_size(struct pvfs_state *pvfs, struct pvfs_filename *name, int fd,
+ off_t size)
+{
+ struct xattr_DosStreams *streams;
+ int i;
+ NTSTATUS status;
+
+ streams = talloc(name, struct xattr_DosStreams);
+ if (streams == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ status = pvfs_streams_load(pvfs, name, fd, streams);
+ if (!NT_STATUS_IS_OK(status)) {
+ ZERO_STRUCTP(streams);
+ }
+
+ for (i=0;i<streams->num_streams;i++) {
+ struct xattr_DosStream *s = &streams->streams[i];
+ if (stream_name_cmp(s->name, name->stream_name) == 0) {
+ s->size = size;
+ s->alloc_size = pvfs_round_alloc_size(pvfs, size);
+ break;
+ }
+ }
+
+ if (i == streams->num_streams) {
+ struct xattr_DosStream *s;
+ streams->streams = talloc_realloc(streams, streams->streams,
+ struct xattr_DosStream,
+ streams->num_streams+1);
+ if (streams->streams == NULL) {
+ talloc_free(streams);
+ return NT_STATUS_NO_MEMORY;
+ }
+ streams->num_streams++;
+ s = &streams->streams[i];
+
+ s->flags = XATTR_STREAM_FLAG_INTERNAL;
+ s->size = size;
+ s->alloc_size = pvfs_round_alloc_size(pvfs, size);
+ s->name = stream_name_normalise(streams, name->stream_name);
+ if (s->name == NULL) {
+ talloc_free(streams);
+ return NT_STATUS_NO_MEMORY;
+ }
+ }
+
+ status = pvfs_streams_save(pvfs, name, fd, streams);
+ talloc_free(streams);
+
+ return status;
+}
+
+
+/*
+ rename a stream
+*/
+NTSTATUS pvfs_stream_rename(struct pvfs_state *pvfs, struct pvfs_filename *name, int fd,
+ const char *new_name, bool overwrite)
+{
+ struct xattr_DosStreams *streams;
+ int i, found_old, found_new;
+ NTSTATUS status;
+
+ streams = talloc(name, struct xattr_DosStreams);
+ if (streams == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ new_name = stream_name_normalise(streams, new_name);
+ if (new_name == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ status = pvfs_streams_load(pvfs, name, fd, streams);
+ if (!NT_STATUS_IS_OK(status)) {
+ ZERO_STRUCTP(streams);
+ }
+
+ /* the default stream always exists */
+ if (strcmp(new_name, "") == 0 ||
+ strcasecmp_m(new_name, ":$DATA") == 0) {
+ return NT_STATUS_OBJECT_NAME_COLLISION;
+ }
+
+ /* try to find the old/new names in the list */
+ found_old = found_new = -1;
+ for (i=0;i<streams->num_streams;i++) {
+ struct xattr_DosStream *s = &streams->streams[i];
+ if (stream_name_cmp(s->name, new_name) == 0) {
+ found_new = i;
+ }
+ if (stream_name_cmp(s->name, name->stream_name) == 0) {
+ found_old = i;
+ }
+ }
+
+ if (found_old == -1) {
+ talloc_free(streams);
+ return NT_STATUS_OBJECT_NAME_NOT_FOUND;
+ }
+
+ if (found_new == -1) {
+ /* a simple rename */
+ struct xattr_DosStream *s = &streams->streams[found_old];
+ s->name = new_name;
+ } else {
+ if (!overwrite) {
+ return NT_STATUS_OBJECT_NAME_COLLISION;
+ }
+ if (found_old != found_new) {
+ /* remove the old one and replace with the new one */
+ streams->streams[found_old].name = new_name;
+ memmove(&streams->streams[found_new],
+ &streams->streams[found_new+1],
+ sizeof(streams->streams[0]) *
+ (streams->num_streams - (found_new+1)));
+ streams->num_streams--;
+ }
+ }
+
+ status = pvfs_streams_save(pvfs, name, fd, streams);
+
+ if (NT_STATUS_IS_OK(status)) {
+
+ /* update the in-memory copy of the name of the open file */
+ talloc_free(name->stream_name);
+ name->stream_name = talloc_strdup(name, new_name);
+
+ talloc_free(streams);
+ }
+
+ return status;
+}
+
+
+/*
+ create the xattr for a alternate data stream
+*/
+NTSTATUS pvfs_stream_create(struct pvfs_state *pvfs,
+ struct pvfs_filename *name,
+ int fd)
+{
+ NTSTATUS status;
+ status = pvfs_xattr_create(pvfs, name->full_name, fd,
+ XATTR_DOSSTREAM_PREFIX, name->stream_name);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+ return pvfs_stream_update_size(pvfs, name, fd, 0);
+}
+
+/*
+ delete the xattr for a alternate data stream
+*/
+NTSTATUS pvfs_stream_delete(struct pvfs_state *pvfs,
+ struct pvfs_filename *name,
+ int fd)
+{
+ NTSTATUS status;
+ struct xattr_DosStreams *streams;
+ int i;
+
+ status = pvfs_xattr_delete(pvfs, name->full_name, fd,
+ XATTR_DOSSTREAM_PREFIX, name->stream_name);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+
+ streams = talloc(name, struct xattr_DosStreams);
+ if (streams == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ status = pvfs_streams_load(pvfs, name, fd, streams);
+ if (!NT_STATUS_IS_OK(status)) {
+ talloc_free(streams);
+ return status;
+ }
+
+ for (i=0;i<streams->num_streams;i++) {
+ struct xattr_DosStream *s = &streams->streams[i];
+ if (stream_name_cmp(s->name, name->stream_name) == 0) {
+ memmove(s, s+1, (streams->num_streams - (i+1)) * sizeof(*s));
+ streams->num_streams--;
+ break;
+ }
+ }
+
+ status = pvfs_streams_save(pvfs, name, fd, streams);
+ talloc_free(streams);
+
+ return status;
+}
+
+/*
+ load a stream into a blob
+*/
+static NTSTATUS pvfs_stream_load(struct pvfs_state *pvfs,
+ TALLOC_CTX *mem_ctx,
+ struct pvfs_filename *name,
+ int fd,
+ size_t estimated_size,
+ DATA_BLOB *blob)
+{
+ NTSTATUS status;
+
+ status = pvfs_xattr_load(pvfs, mem_ctx, name->full_name, fd,
+ XATTR_DOSSTREAM_PREFIX,
+ name->stream_name, estimated_size, blob);
+
+ if (NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND)) {
+ /* try with a case insensitive match */
+ struct xattr_DosStreams *streams;
+ int i;
+
+ streams = talloc(mem_ctx, struct xattr_DosStreams);
+ if (streams == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ status = pvfs_streams_load(pvfs, name, fd, streams);
+ if (!NT_STATUS_IS_OK(status)) {
+ talloc_free(streams);
+ return NT_STATUS_NOT_FOUND;
+ }
+ for (i=0;i<streams->num_streams;i++) {
+ struct xattr_DosStream *s = &streams->streams[i];
+ if (stream_name_cmp(s->name, name->stream_name) == 0) {
+ status = pvfs_xattr_load(pvfs, mem_ctx, name->full_name, fd,
+ XATTR_DOSSTREAM_PREFIX,
+ s->name, estimated_size, blob);
+ talloc_free(streams);
+ return status;
+ }
+ }
+ talloc_free(streams);
+ return NT_STATUS_NOT_FOUND;
+ }
+
+ return status;
+}
+
+/*
+ the equivalent of pread() on a stream
+*/
+ssize_t pvfs_stream_read(struct pvfs_state *pvfs,
+ struct pvfs_file_handle *h, void *data, size_t count, off_t offset)
+{
+ NTSTATUS status;
+ DATA_BLOB blob;
+ if (count == 0) {
+ return 0;
+ }
+ status = pvfs_stream_load(pvfs, h, h->name, h->fd, offset+count, &blob);
+ if (!NT_STATUS_IS_OK(status)) {
+ errno = EIO;
+ return -1;
+ }
+ if (offset >= blob.length) {
+ data_blob_free(&blob);
+ return 0;
+ }
+ if (count > blob.length - offset) {
+ count = blob.length - offset;
+ }
+ memcpy(data, blob.data + offset, count);
+ data_blob_free(&blob);
+ return count;
+}
+
+
+/*
+ the equivalent of pwrite() on a stream
+*/
+ssize_t pvfs_stream_write(struct pvfs_state *pvfs,
+ struct pvfs_file_handle *h, const void *data, size_t count, off_t offset)
+{
+ NTSTATUS status;
+ DATA_BLOB blob;
+ if (count == 0) {
+ return 0;
+ }
+
+ if (count+offset > XATTR_MAX_STREAM_SIZE) {
+ if (!pvfs->ea_db || count+offset > XATTR_MAX_STREAM_SIZE_TDB) {
+ errno = ENOSPC;
+ return -1;
+ }
+ }
+
+ /* we have to load the existing stream, then modify, then save */
+ status = pvfs_stream_load(pvfs, h, h->name, h->fd, offset+count, &blob);
+ if (!NT_STATUS_IS_OK(status)) {
+ blob = data_blob(NULL, 0);
+ }
+ if (count+offset > blob.length) {
+ blob.data = talloc_realloc(blob.data, blob.data, uint8_t, count+offset);
+ if (blob.data == NULL) {
+ errno = ENOMEM;
+ return -1;
+ }
+ if (offset > blob.length) {
+ memset(blob.data+blob.length, 0, offset - blob.length);
+ }
+ blob.length = count+offset;
+ }
+ memcpy(blob.data + offset, data, count);
+
+ status = pvfs_xattr_save(pvfs, h->name->full_name, h->fd, XATTR_DOSSTREAM_PREFIX,
+ h->name->stream_name, &blob);
+ if (!NT_STATUS_IS_OK(status)) {
+ data_blob_free(&blob);
+ /* getting this error mapping right is probably
+ not worth it */
+ errno = ENOSPC;
+ return -1;
+ }
+
+ status = pvfs_stream_update_size(pvfs, h->name, h->fd, blob.length);
+
+ data_blob_free(&blob);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ errno = EIO;
+ return -1;
+ }
+
+ return count;
+}
+
+/*
+ the equivalent of truncate() on a stream
+*/
+NTSTATUS pvfs_stream_truncate(struct pvfs_state *pvfs,
+ struct pvfs_filename *name, int fd, off_t length)
+{
+ NTSTATUS status;
+ DATA_BLOB blob;
+
+ if (length > XATTR_MAX_STREAM_SIZE) {
+ if (!pvfs->ea_db || length > XATTR_MAX_STREAM_SIZE_TDB) {
+ return NT_STATUS_DISK_FULL;
+ }
+ }
+
+ /* we have to load the existing stream, then modify, then save */
+ status = pvfs_stream_load(pvfs, name, name, fd, length, &blob);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+ if (length <= blob.length) {
+ blob.length = length;
+ } else if (length > blob.length) {
+ blob.data = talloc_realloc(blob.data, blob.data, uint8_t, length);
+ if (blob.data == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+ memset(blob.data+blob.length, 0, length - blob.length);
+ blob.length = length;
+ }
+
+ status = pvfs_xattr_save(pvfs, name->full_name, fd, XATTR_DOSSTREAM_PREFIX,
+ name->stream_name, &blob);
+
+ if (NT_STATUS_IS_OK(status)) {
+ status = pvfs_stream_update_size(pvfs, name, fd, blob.length);
+ }
+ data_blob_free(&blob);
+
+ return status;
+}
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