1 files changed, 242 insertions, 0 deletions
diff --git a/libcli/smb/smb2_create_blob.c b/libcli/smb/smb2_create_blob.c
new file mode 100644
index 0000000..ecd61e0
--- /dev/null
+++ b/libcli/smb/smb2_create_blob.c
@@ -0,0 +1,242 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   SMB2 Create Context Blob handling
+
+   Copyright (C) Andrew Tridgell 2005
+   Copyright (C) Stefan Metzmacher 2008-2009
+
+   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 "../libcli/smb/smb_common.h"
+
+static size_t smb2_create_blob_padding(uint32_t offset, size_t n)
+{
+	if ((offset & (n-1)) == 0) return 0;
+	return n - (offset & (n-1));
+}
+
+/*
+  parse a set of SMB2 create blobs
+*/
+NTSTATUS smb2_create_blob_parse(TALLOC_CTX *mem_ctx, const DATA_BLOB buffer,
+				struct smb2_create_blobs *blobs)
+{
+	const uint8_t *data = buffer.data;
+	uint32_t remaining = buffer.length;
+
+	while (remaining > 0) {
+		uint32_t next;
+		uint32_t name_offset, name_length;
+		uint32_t data_offset;
+		uint32_t data_length;
+		char *tag;
+		DATA_BLOB b;
+		NTSTATUS status;
+
+		if (remaining < 16) {
+			return NT_STATUS_INVALID_PARAMETER;
+		}
+		next        = IVAL(data, 0);
+		name_offset = SVAL(data, 4);
+		name_length = SVAL(data, 6);
+#if 0
+		reserved    = SVAL(data, 8);
+#endif
+		data_offset = SVAL(data, 10);
+		data_length = IVAL(data, 12);
+
+		if ((next & 0x7) != 0 ||
+		    next > remaining ||
+		    name_offset != 16 ||
+		    name_length < 4 ||
+		    name_offset + name_length > remaining ||
+		    (data_offset & 0x7) != 0 ||
+		    (data_offset && (data_offset < name_offset + name_length)) ||
+		    (data_offset > remaining) ||
+		    (data_offset + (uint64_t)data_length > remaining)) {
+			return NT_STATUS_INVALID_PARAMETER;
+		}
+
+		tag = talloc_strndup(mem_ctx, (const char *)data + name_offset, name_length);
+		if (tag == NULL) {
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		b = data_blob_const(data+data_offset, data_length);
+		status = smb2_create_blob_add(mem_ctx, blobs, tag, b);
+		if (!NT_STATUS_IS_OK(status)) {
+			return status;
+		}
+
+		talloc_free(tag);
+
+		if (next == 0) break;
+
+		remaining -= next;
+		data += next;
+
+		if (remaining < 16) {
+			return NT_STATUS_INVALID_PARAMETER;
+		}
+	}
+
+	return NT_STATUS_OK;
+}
+
+
+/*
+  add a blob to a smb2_create attribute blob
+*/
+static NTSTATUS smb2_create_blob_push_one(TALLOC_CTX *mem_ctx, DATA_BLOB *buffer,
+					  const struct smb2_create_blob *blob,
+					  bool last)
+{
+	uint32_t ofs = buffer->length;
+	size_t tag_length = strlen(blob->tag);
+	size_t blob_offset = 0;
+	size_t blob_pad = 0;
+	size_t next_offset = 0;
+	size_t next_pad = 0;
+	bool ok;
+
+	blob_offset = 0x10 + tag_length;
+	blob_pad = smb2_create_blob_padding(blob_offset, 8);
+	next_offset = blob_offset + blob_pad + blob->data.length;
+	if (!last) {
+		next_pad = smb2_create_blob_padding(next_offset, 8);
+	}
+
+	ok = data_blob_realloc(mem_ctx, buffer,
+			       buffer->length + next_offset + next_pad);
+	if (!ok) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	if (last) {
+		SIVAL(buffer->data, ofs+0x00, 0);
+	} else {
+		SIVAL(buffer->data, ofs+0x00, next_offset + next_pad);
+	}
+	SSVAL(buffer->data, ofs+0x04, 0x10); /* offset of tag */
+	SIVAL(buffer->data, ofs+0x06, tag_length); /* tag length */
+	SSVAL(buffer->data, ofs+0x0A, blob_offset + blob_pad); /* offset of data */
+	SIVAL(buffer->data, ofs+0x0C, blob->data.length);
+	memcpy(buffer->data+ofs+0x10, blob->tag, tag_length);
+	if (blob_pad > 0) {
+		memset(buffer->data+ofs+blob_offset, 0, blob_pad);
+		blob_offset += blob_pad;
+	}
+	memcpy(buffer->data+ofs+blob_offset, blob->data.data, blob->data.length);
+	if (next_pad > 0) {
+		memset(buffer->data+ofs+next_offset, 0, next_pad);
+	}
+
+	return NT_STATUS_OK;
+}
+
+
+/*
+  create a buffer of a set of create blobs
+*/
+NTSTATUS smb2_create_blob_push(TALLOC_CTX *mem_ctx, DATA_BLOB *buffer,
+			       const struct smb2_create_blobs blobs)
+{
+	uint32_t i;
+	NTSTATUS status;
+
+	*buffer = (DATA_BLOB) { 0 };
+	for (i=0; i < blobs.num_blobs; i++) {
+		bool last = false;
+		const struct smb2_create_blob *c;
+
+		if ((i + 1) == blobs.num_blobs) {
+			last = true;
+		}
+
+		c = &blobs.blobs[i];
+		status = smb2_create_blob_push_one(mem_ctx, buffer, c, last);
+		if (!NT_STATUS_IS_OK(status)) {
+			return status;
+		}
+	}
+	return NT_STATUS_OK;
+}
+
+
+NTSTATUS smb2_create_blob_add(TALLOC_CTX *mem_ctx, struct smb2_create_blobs *b,
+			      const char *tag, DATA_BLOB data)
+{
+	struct smb2_create_blob *array;
+
+	array = talloc_realloc(mem_ctx, b->blobs,
+			       struct smb2_create_blob,
+			       b->num_blobs + 1);
+	NT_STATUS_HAVE_NO_MEMORY(array);
+	b->blobs = array;
+
+	b->blobs[b->num_blobs].tag = talloc_strdup(b->blobs, tag);
+	NT_STATUS_HAVE_NO_MEMORY(b->blobs[b->num_blobs].tag);
+
+	if (data.data) {
+		b->blobs[b->num_blobs].data = data_blob_talloc(b->blobs,
+							       data.data,
+							       data.length);
+		NT_STATUS_HAVE_NO_MEMORY(b->blobs[b->num_blobs].data.data);
+	} else {
+		b->blobs[b->num_blobs].data = data_blob_null;
+	}
+
+	b->num_blobs += 1;
+
+	return NT_STATUS_OK;
+}
+
+/*
+ * return the first blob with the given tag
+ */
+struct smb2_create_blob *smb2_create_blob_find(const struct smb2_create_blobs *b,
+					       const char *tag)
+{
+	uint32_t i;
+
+	if (b == NULL) {
+		return NULL;
+	}
+
+	for (i=0; i < b->num_blobs; i++) {
+		if (strcmp(b->blobs[i].tag, tag) == 0) {
+			return &b->blobs[i];
+		}
+	}
+
+	return NULL;
+}
+
+void smb2_create_blob_remove(struct smb2_create_blobs *b, const char *tag)
+{
+	struct smb2_create_blob *blob = smb2_create_blob_find(b, tag);
+
+	if (blob == NULL) {
+		return;
+	}
+
+	TALLOC_FREE(blob->tag);
+	data_blob_free(&blob->data);
+
+	*blob = b->blobs[b->num_blobs-1];
+	b->num_blobs -= 1;
+}