fixed a problem with length limited ldap values

The core ldb code for string matching assumed NULL terminated strings,
whereas the anr module used data_blob_const() to effectively truncate
a ldb_val by changing its length. The ldb code is supposed to be based
around length limited blobs, not NULL terminated strings, so the
correct fix was to change the string comparison functions to be length
limited
(This used to be commit 26c6aa5a80ffaf06fc33f30a6533f8f16ef538bc)

2 files changed, 23 insertions, 16 deletions

diff --git a/source4/lib/ldb/common/attrib_handlers.c b/source4/lib/ldb/common/attrib_handlers.c
index 8ed2763d4d..fb57e2dadc 100644
--- a/source4/lib/ldb/common/attrib_handlers.c
+++ b/source4/lib/ldb/common/attrib_handlers.c
@@ -55,11 +55,12 @@ int ldb_handler_fold(struct ldb_context *ldb, void *mem_ctx,
 {
 	char *s, *t;
 	int l;
+
 	if (!in || !out || !(in->data)) {
 		return -1;
 	}
 
-	out->data = (uint8_t *)ldb_casefold(ldb, mem_ctx, (const char *)(in->data));
+	out->data = (uint8_t *)ldb_casefold(ldb, mem_ctx, (const char *)(in->data), in->length);
 	if (out->data == NULL) {
 		ldb_debug(ldb, LDB_DEBUG_ERROR, "ldb_handler_fold: unable to casefold string [%s]", in->data);
 		return -1;
@@ -153,13 +154,14 @@ int ldb_comparison_fold(struct ldb_context *ldb, void *mem_ctx,
 			       const struct ldb_val *v1, const struct ldb_val *v2)
 {
 	const char *s1=(const char *)v1->data, *s2=(const char *)v2->data;
+	size_t n1 = v1->length, n2 = v2->length;
 	const char *u1, *u2;
 	char *b1, *b2;
 	int ret;
-	while (*s1 == ' ') s1++;
-	while (*s2 == ' ') s2++;
+	while (*s1 == ' ' && n1) { s1++; n1--; };
+	while (*s2 == ' ' && n2) { s2++; n2--; };
 	/* TODO: make utf8 safe, possibly with helper function from application */
-	while (*s1 && *s2) {
+	while (*s1 && *s2 && n1 && n2) {
 		/* the first 127 (0x7F) chars are ascii and utf8 guarantes they
 		 * never appear in multibyte sequences */
 		if (((unsigned char)s1[0]) & 0x80) goto utf8str;
@@ -167,10 +169,11 @@ int ldb_comparison_fold(struct ldb_context *ldb, void *mem_ctx,
 		if (toupper((unsigned char)*s1) != toupper((unsigned char)*s2))
 			break;
 		if (*s1 == ' ') {
-			while (s1[0] == s1[1]) s1++;
-			while (s2[0] == s2[1]) s2++;
+			while (s1[0] == s1[1] && n1) { s1++; n1--; }
+			while (s2[0] == s2[1] && n2) { s2++; n2--; }
 		}
 		s1++; s2++;
+		n1--; n2--;
 	}
 	if (! (*s1 && *s2)) {
 		/* check for trailing spaces only if one of the pointers
@@ -178,15 +181,18 @@ int ldb_comparison_fold(struct ldb_context *ldb, void *mem_ctx,
 		 * can mistakenly match.
 		 * ex. "domain users" <-> "domainUpdates"
 		 */
-		while (*s1 == ' ') s1++;
-		while (*s2 == ' ') s2++;
+		while (*s1 == ' ') { s1++; n1--; }
+		while (*s2 == ' ') { s2++; n2--; }
+	}
+	if (n1 != n2) {
+		return n1 - n2;
 	}
 	return (int)(toupper(*s1)) - (int)(toupper(*s2));
 
 utf8str:
 	/* no need to recheck from the start, just from the first utf8 char found */
-	b1 = ldb_casefold(ldb, mem_ctx, s1);
-	b2 = ldb_casefold(ldb, mem_ctx, s2);
+	b1 = ldb_casefold(ldb, mem_ctx, s1, n1);
+	b2 = ldb_casefold(ldb, mem_ctx, s2, n2);
 
 	if (b1 && b2) {
 		/* Both strings converted correctly */
@@ -221,6 +227,7 @@ utf8str:
 	return ret;
 }
 
+
 /*
   canonicalise a attribute in DN format
 */
diff --git a/source4/lib/ldb/common/ldb_utf8.c b/source4/lib/ldb/common/ldb_utf8.c
index b7b4a60122..69ee2b6964 100644
--- a/source4/lib/ldb/common/ldb_utf8.c
+++ b/source4/lib/ldb/common/ldb_utf8.c
@@ -40,8 +40,8 @@
   function to handle utf8 caseless comparisons
  */
 void ldb_set_utf8_fns(struct ldb_context *ldb,
-			void *context,
-			char *(*casefold)(void *, void *, const char *))
+		      void *context,
+		      char *(*casefold)(void *, void *, const char *, size_t))
 {
 	if (context)
 		ldb->utf8_fns.context = context;
@@ -53,10 +53,10 @@ void ldb_set_utf8_fns(struct ldb_context *ldb,
   a simple case folding function
   NOTE: does not handle UTF8
 */
-char *ldb_casefold_default(void *context, void *mem_ctx, const char *s)
+char *ldb_casefold_default(void *context, void *mem_ctx, const char *s, size_t n)
 {
 	int i;
-	char *ret = talloc_strdup(mem_ctx, s);
+	char *ret = talloc_strndup(mem_ctx, s, n);
 	if (!s) {
 		errno = ENOMEM;
 		return NULL;
@@ -72,9 +72,9 @@ void ldb_set_utf8_default(struct ldb_context *ldb)
 	ldb_set_utf8_fns(ldb, NULL, ldb_casefold_default);
 }
 
-char *ldb_casefold(struct ldb_context *ldb, void *mem_ctx, const char *s)
+char *ldb_casefold(struct ldb_context *ldb, void *mem_ctx, const char *s, size_t n)
 {
-	return ldb->utf8_fns.casefold(ldb->utf8_fns.context, mem_ctx, s);
+	return ldb->utf8_fns.casefold(ldb->utf8_fns.context, mem_ctx, s, n);
 }
 
 /*