From: Alan T. DeKok <aland@freeradius.org>
Date: Sun, 11 Dec 2022 15:11:16 +0000 (-0500)
Subject: make conditional parser use fr_skip_string()
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fff3dfaf7517d179fe3ffaf8fe25f2a0309142fa;p=thirdparty%2Ffreeradius-server.git

make conditional parser use fr_skip_string()

in the interest of common code.
---

diff --git a/src/lib/server/cf_file.c b/src/lib/server/cf_file.c
index 53773c3f04d..616bbb518f8 100644
--- a/src/lib/server/cf_file.c
+++ b/src/lib/server/cf_file.c
@@ -1166,47 +1166,6 @@ static int process_template(cf_stack_t *stack)
 
 static int cf_file_fill(cf_stack_t *stack);
 
-static uint8_t const *skip_string(uint8_t const *p, char c)
-{
-	while (*p >= ' ') {
-		if (*p == c) {
-			p++;
-			return p;
-		}
-
-		if (*p != '\\') {
-			p++;
-			continue;
-		}
-
-		if (p[1] < ' ') {
-			return NULL;
-		}
-
-		if (!isdigit((int) p[1])) {
-			p += 2;
-			continue;
-		}
-
-		/*
-		 *	Double-quoted strings use \000
-		 *	Regexes use \0
-		 */
-		if (c == '/') {
-			p++;
-			continue;
-		}
-
-		if (!isdigit((int) p[2]) || !isdigit((int) p[3])) {
-			return NULL;
-		}
-
-		p += 4;
-	}
-
-	return NULL;
-}
-
 /*
  *	Expansions can contain other expansions, but can't contain regexes.
  */
@@ -1241,10 +1200,12 @@ static uint8_t const *skip_expanse(uint8_t const *p)
 		}
 
 		if ((*p == '"') || (*p == '\'') || (*p == '`')) {
-			char c = *p++;
+			ssize_t slen;
 
-			p = skip_string(p, c);
-			if (!p) return NULL;
+			slen = fr_skip_string((char const *) p, NULL);
+			if (slen <= 0) return NULL;
+
+			p += slen;
 			continue;
 		}
 
@@ -1309,7 +1270,6 @@ static CONF_ITEM *process_if(cf_stack_t *stack)
 	 *
 	 */
 	while (true) {
-		char c;
 		bool found = false;
 		bool was_regex = false;
 		int depth = 0;
@@ -1377,15 +1337,18 @@ static CONF_ITEM *process_if(cf_stack_t *stack)
 			 *	We have a quoted string, ignore '(' and ')' within it.
 			 */
 			if ((*p == '"') || (*p == '\'') || (*p == '`') || (was_regex && (*p == '/'))) {
+				ssize_t my_slen;
+
 				was_regex = false;
-				c = *p++;
-				p = skip_string(p, c);
-				if (!p) {
+
+				my_slen = fr_skip_string((char const *) p, NULL);
+				if (my_slen <= 0) {
 					cf_log_err(cs, "Unexpected end of string");
 					talloc_free(cs);
 					return NULL;
 				}
 
+				p += my_slen;
 				continue;
 			}
 
diff --git a/src/lib/util/token.c b/src/lib/util/token.c
index 23481d134d3..4a3190df83f 100644
--- a/src/lib/util/token.c
+++ b/src/lib/util/token.c
@@ -491,6 +491,14 @@ char const *fr_token_name(int token)
 }
 
 
+/**  Skip a quoted string.
+ *
+ *  @param[in] start	start of the string, pointing to the quotation character
+ *  @param[in] end	end of the string (or NULL for zero-terminated strings)
+ *  @return
+ *	>0 length of the string which was parsed
+ *	<=0 on error
+ */
 ssize_t fr_skip_string(char const *start, char const *end)
 {
 	char const *p = start;
@@ -498,22 +506,59 @@ ssize_t fr_skip_string(char const *start, char const *end)
 
 	quote = *(p++);
 
-	while (p < end) {
+	while ((end && (p < end)) || *p) {
+		/*
+		 *	Stop at the quotation character
+		 */
 		if (*p == quote) {
 			p++;
 			return p - start;
 		}
 
-		if (*p == '\\') {
-			if (((p + 1) >= end) || !p[1]) {
-				break;
-			}
+		/*
+		 *	Not an escape character: it's OK.
+		 */
+		if (*p != '\\') {
+			p++;
+			continue;
+		}
 
+		if (end && ((p + 2) >= end)) {
+		fail:
+			fr_strerror_const("Unexpected escape at end of string");
+			return -(p - start);
+		}
+
+		/*
+		 *	Escape at EOL is not allowed.
+		 */
+		if (p[1] < ' ') goto fail;
+
+		/*
+		 *	\r or \n, etc.
+		 */
+		if (!isdigit((int) p[1])) {
 			p += 2;
 			continue;
 		}
 
-		p++;
+		/*
+		 *	Double-quoted strings use \000
+		 *	Regexes use \0
+		 */
+		if (quote == '/') {
+			p++;
+			continue;
+		}
+
+		if (end && ((p + 4) >= end)) goto fail;
+
+		if (!isdigit((int) p[2]) || !isdigit((int) p[3])) {
+			fr_strerror_const("Invalid octal escape");
+			return -(p - start);
+		}
+
+		p += 4;
 	}
 
 	/*
@@ -522,3 +567,4 @@ ssize_t fr_skip_string(char const *start, char const *end)
 	fr_strerror_const("Unexpected end of string");
 	return -(p - start);
 }
+