/* 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 equvalent 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 equvalent 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 equvalent 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; }