X-Git-Url: https://git.librecmc.org/?p=oweals%2Flibubox.git;a=blobdiff_plain;f=blob.c;h=433becb904f54d4e0b3fb186756f62c71beb0ba5;hp=4817fd4dc218758d7f75d7d0168f67e0978d3943;hb=HEAD;hpb=51711be6251be4ae5e53f9369ae04598b06df0e7

diff --git a/blob.c b/blob.c
index 4817fd4..433becb 100644
--- a/blob.c
+++ b/blob.c
@@ -3,14 +3,17 @@
  *
  * Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License version 2.1
- * as published by the Free Software Foundation
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
  *
- * 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.
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
 #include "blob.h"
@@ -18,12 +21,15 @@
 static bool
 blob_buffer_grow(struct blob_buf *buf, int minlen)
 {
+	struct blob_buf *new;
 	int delta = ((minlen / 256) + 1) * 256;
-	buf->buflen += delta;
-	buf->buf = realloc(buf->buf, buf->buflen);
-	if (buf->buf)
-		memset(buf->buf + buf->buflen - delta, 0, delta);
-	return !!buf->buf;
+	new = realloc(buf->buf, buf->buflen + delta);
+	if (new) {
+		buf->buf = new;
+		memset(buf->buf + buf->buflen, 0, delta);
+		buf->buflen += delta;
+	}
+	return !!new;
 }
 
 static void
@@ -37,30 +43,38 @@ blob_init(struct blob_attr *attr, int id, unsigned int len)
 static inline struct blob_attr *
 offset_to_attr(struct blob_buf *buf, int offset)
 {
-	void *ptr = (char *)buf->buf + offset;
+	void *ptr = (char *)buf->buf + offset - BLOB_COOKIE;
 	return ptr;
 }
 
 static inline int
 attr_to_offset(struct blob_buf *buf, struct blob_attr *attr)
 {
-	return (char *)attr - (char *) buf->buf;
+	return (char *)attr - (char *) buf->buf + BLOB_COOKIE;
+}
+
+bool
+blob_buf_grow(struct blob_buf *buf, int required)
+{
+	int offset_head = attr_to_offset(buf, buf->head);
+
+	if (!buf->grow || !buf->grow(buf, required))
+		return false;
+
+	buf->head = offset_to_attr(buf, offset_head);
+	return true;
 }
 
 static struct blob_attr *
 blob_add(struct blob_buf *buf, struct blob_attr *pos, int id, int payload)
 {
 	int offset = attr_to_offset(buf, pos);
-	int required = (offset + sizeof(struct blob_attr) + payload) - buf->buflen;
+	int required = (offset - BLOB_COOKIE + sizeof(struct blob_attr) + payload) - buf->buflen;
 	struct blob_attr *attr;
 
 	if (required > 0) {
-		int offset_head = attr_to_offset(buf, buf->head);
-
-		if (!buf->grow || !buf->grow(buf, required))
+		if (!blob_buf_grow(buf, required))
 			return NULL;
-
-		buf->head = offset_to_attr(buf, offset_head);
 		attr = offset_to_attr(buf, offset);
 	} else {
 		attr = pos;
@@ -106,10 +120,9 @@ blob_fill_pad(struct blob_attr *attr)
 void
 blob_set_raw_len(struct blob_attr *attr, unsigned int len)
 {
-	int id = blob_id(attr);
 	len &= BLOB_ATTR_LEN_MASK;
-	len |= (id << BLOB_ATTR_ID_SHIFT) & BLOB_ATTR_ID_MASK;
-	attr->id_len = cpu_to_be32(len);
+	attr->id_len &= ~cpu_to_be32(BLOB_ATTR_LEN_MASK);
+	attr->id_len |= cpu_to_be32(len);
 }
 
 struct blob_attr *
@@ -126,7 +139,23 @@ blob_new(struct blob_buf *buf, int id, int payload)
 }
 
 struct blob_attr *
-blob_put(struct blob_buf *buf, int id, const void *ptr, int len)
+blob_put_raw(struct blob_buf *buf, const void *ptr, unsigned int len)
+{
+	struct blob_attr *attr;
+
+	if (len < sizeof(struct blob_attr) || !ptr)
+		return NULL;
+
+	attr = blob_add(buf, blob_next(buf->head), 0, len - sizeof(struct blob_attr));
+	if (!attr)
+		return NULL;
+	blob_set_raw_len(buf->head, blob_pad_len(buf->head) + len);
+	memcpy(attr, ptr, len);
+	return attr;
+}
+
+struct blob_attr *
+blob_put(struct blob_buf *buf, int id, const void *ptr, unsigned int len)
 {
 	struct blob_attr *attr;
 
@@ -144,6 +173,8 @@ blob_nest_start(struct blob_buf *buf, int id)
 {
 	unsigned long offset = attr_to_offset(buf, buf->head);
 	buf->head = blob_new(buf, id, 0);
+	if (!buf->head)
+		return NULL;
 	return (void *) offset;
 }
 
@@ -155,16 +186,17 @@ blob_nest_end(struct blob_buf *buf, void *cookie)
 	buf->head = attr;
 }
 
-static const int blob_type_minlen[BLOB_ATTR_LAST] = {
+static const size_t blob_type_minlen[BLOB_ATTR_LAST] = {
 	[BLOB_ATTR_STRING] = 1,
 	[BLOB_ATTR_INT8] = sizeof(uint8_t),
 	[BLOB_ATTR_INT16] = sizeof(uint16_t),
 	[BLOB_ATTR_INT32] = sizeof(uint32_t),
 	[BLOB_ATTR_INT64] = sizeof(uint64_t),
+	[BLOB_ATTR_DOUBLE] = sizeof(double),
 };
 
 bool
-blob_check_type(const void *ptr, int len, int type)
+blob_check_type(const void *ptr, unsigned int len, int type)
 {
 	const char *data = ptr;
 
@@ -185,44 +217,90 @@ blob_check_type(const void *ptr, int len, int type)
 	return true;
 }
 
-int
-blob_parse(struct blob_attr *attr, struct blob_attr **data, const struct blob_attr_info *info, int max)
+static int
+blob_parse_attr(struct blob_attr *attr, size_t attr_len, struct blob_attr **data, const struct blob_attr_info *info, int max)
 {
-	struct blob_attr *pos;
+	int id;
+	size_t len;
 	int found = 0;
-	int rem;
-
-	memset(data, 0, sizeof(struct blob_attr *) * max);
-	blob_for_each_attr(pos, attr, rem) {
-		int id = blob_id(pos);
-		int len = blob_len(pos);
+	size_t data_len;
 
-		if (id >= max)
-			continue;
+	if (!attr || attr_len < sizeof(struct blob_attr))
+		return 0;
 
-		if (info) {
-			int type = info[id].type;
+	id = blob_id(attr);
+	if (id >= max)
+		return 0;
 
-			if (type < BLOB_ATTR_LAST) {
-				if (!blob_check_type(blob_data(pos), len, type))
-					continue;
-			}
+	len = blob_raw_len(attr);
+	if (len > attr_len || len < sizeof(struct blob_attr))
+		return 0;
 
-			if (info[id].minlen && len < info[id].minlen)
-				continue;
+	data_len = blob_len(attr);
+	if (data_len > len)
+		return 0;
 
-			if (info[id].maxlen && len > info[id].maxlen)
-				continue;
+	if (info) {
+		int type = info[id].type;
 
-			if (info[id].validate && !info[id].validate(&info[id], attr))
-				continue;
+		if (type < BLOB_ATTR_LAST) {
+			if (!blob_check_type(blob_data(attr), data_len, type))
+				return 0;
 		}
 
-		if (!data[id])
-			found++;
+		if (info[id].minlen && len < info[id].minlen)
+			return 0;
+
+		if (info[id].maxlen && len > info[id].maxlen)
+			return 0;
 
-		data[id] = pos;
+		if (info[id].validate && !info[id].validate(&info[id], attr))
+			return 0;
 	}
+
+	if (!data[id])
+		found++;
+
+	data[id] = attr;
+	return found;
+}
+
+int
+blob_parse_untrusted(struct blob_attr *attr, size_t attr_len, struct blob_attr **data, const struct blob_attr_info *info, int max)
+{
+	struct blob_attr *pos;
+	size_t len = 0;
+	int found = 0;
+	size_t rem;
+
+	if (!attr || attr_len < sizeof(struct blob_attr))
+		return 0;
+
+	len = blob_raw_len(attr);
+	if (attr_len < len)
+		return 0;
+
+	memset(data, 0, sizeof(struct blob_attr *) * max);
+	blob_for_each_attr_len(pos, attr, len, rem) {
+		found += blob_parse_attr(pos, rem, data, info, max);
+	}
+
+	return found;
+}
+
+/* use only on trusted input, otherwise consider blob_parse_untrusted */
+int
+blob_parse(struct blob_attr *attr, struct blob_attr **data, const struct blob_attr_info *info, int max)
+{
+	struct blob_attr *pos;
+	int found = 0;
+	size_t rem;
+
+	memset(data, 0, sizeof(struct blob_attr *) * max);
+	blob_for_each_attr(pos, attr, rem) {
+		found += blob_parse_attr(pos, rem, data, info, max);
+	}
+
 	return found;
 }
 
@@ -240,3 +318,17 @@ blob_attr_equal(const struct blob_attr *a1, const struct blob_attr *a2)
 
 	return !memcmp(a1, a2, blob_pad_len(a1));
 }
+
+struct blob_attr *
+blob_memdup(struct blob_attr *attr)
+{
+	struct blob_attr *ret;
+	int size = blob_pad_len(attr);
+
+	ret = malloc(size);
+	if (!ret)
+		return NULL;
+
+	memcpy(ret, attr, size);
+	return ret;
+}