From e84c698fefb4d1f69ce687736811cf9474437195 Mon Sep 17 00:00:00 2001
From: omjego <jadhavos43@gmail.com>
Date: Tue, 25 Aug 2020 08:16:07 +0000
Subject: [PATCH 1/2] Fix parsing to parse query string with single space char.

When passed ' ' as a query string, the server crashes cause of illegal memory access done in httplib::detail::split. Have added checks to make sure the split function has a valid string with length > 0.
---
 httplib.h    | 10 ++++++++--
 test/test.cc |  7 +++++++
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/httplib.h b/httplib.h
index 7e9f2a53af..cc9612177e 100644
--- a/httplib.h
+++ b/httplib.h
@@ -1454,8 +1454,11 @@ inline std::pair<int, int> trim(const char *b, const char *e, int left,
 template <class Fn> void split(const char *b, const char *e, char d, Fn fn) {
   int i = 0;
   int beg = 0;
+  if(!b) {
+    return;
+  }
 
-  while (e ? (b + i != e) : (b[i] != '\0')) {
+  while (e ? (b + i < e) : (b[i] != '\0')) {
     if (b[i] == d) {
       auto r = trim(b, e, beg, i);
       fn(&b[r.first], &b[r.second]);
@@ -2847,7 +2850,10 @@ inline void parse_query_text(const std::string &s, Params &params) {
         val.assign(b2, e2);
       }
     });
-    params.emplace(decode_url(key, true), decode_url(val, true));
+
+    if(!key.empty()) {
+      params.emplace(decode_url(key, true), decode_url(val, true));
+    }
   });
 }
 
diff --git a/test/test.cc b/test/test.cc
index c04bb0c90a..6bb7fbb155 100644
--- a/test/test.cc
+++ b/test/test.cc
@@ -66,6 +66,13 @@ TEST(SplitTest, ParseQueryString) {
   EXPECT_EQ("val3", dic.find("key3")->second);
 }
 
+TEST(SplitTest, ParseQueryWithSingleSpaceChar) {
+  string s = " ";
+  Params dict;
+  detail::parse_query_text(s, dict);
+  EXPECT_TRUE(dict.empty());
+}
+
 TEST(ParseQueryTest, ParseQueryString) {
   string s = "key1=val1&key2=val2&key3=val3";
   Params dic;

From f1807bb789fcad4f5b61fb32f3e252ab30a68993 Mon Sep 17 00:00:00 2001
From: omjego <jadhavos43@gmail.com>
Date: Thu, 27 Aug 2020 13:53:12 +0000
Subject: [PATCH 2/2] Fix parsing to parse query string with single space char.

---
 httplib.h    | 12 ++++++------
 test/test.cc | 21 ++++++++++++++++-----
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/httplib.h b/httplib.h
index cc9612177e..18616c758f 100644
--- a/httplib.h
+++ b/httplib.h
@@ -1454,14 +1454,13 @@ inline std::pair<int, int> trim(const char *b, const char *e, int left,
 template <class Fn> void split(const char *b, const char *e, char d, Fn fn) {
   int i = 0;
   int beg = 0;
-  if(!b) {
-    return;
-  }
 
   while (e ? (b + i < e) : (b[i] != '\0')) {
     if (b[i] == d) {
       auto r = trim(b, e, beg, i);
-      fn(&b[r.first], &b[r.second]);
+      if (r.first < r.second) {
+        fn(&b[r.first], &b[r.second]);
+      }
       beg = i + 1;
     }
     i++;
@@ -1469,7 +1468,9 @@ template <class Fn> void split(const char *b, const char *e, char d, Fn fn) {
 
   if (i) {
     auto r = trim(b, e, beg, i);
-    fn(&b[r.first], &b[r.second]);
+    if (r.first < r.second) {
+      fn(&b[r.first], &b[r.second]);
+    }
   }
 }
 
@@ -2835,7 +2836,6 @@ inline std::string params_to_query_str(const Params &params) {
     query += "=";
     query += encode_url(it->second);
   }
-
   return query;
 }
 
diff --git a/test/test.cc b/test/test.cc
index 6bb7fbb155..29f60ca398 100644
--- a/test/test.cc
+++ b/test/test.cc
@@ -66,13 +66,24 @@ TEST(SplitTest, ParseQueryString) {
   EXPECT_EQ("val3", dic.find("key3")->second);
 }
 
-TEST(SplitTest, ParseQueryWithSingleSpaceChar) {
-  string s = " ";
-  Params dict;
-  detail::parse_query_text(s, dict);
-  EXPECT_TRUE(dict.empty());
+TEST(SplitTest, ParseInvalidQueryTests) {
+
+  {
+    string s = " ";
+    Params dict;
+    detail::parse_query_text(s, dict);
+    EXPECT_TRUE(dict.empty());
+  }
+
+  {
+    string s = " = =";
+    Params dict;
+    detail::parse_query_text(s, dict);
+    EXPECT_TRUE(dict.empty());
+  }
 }
 
+
 TEST(ParseQueryTest, ParseQueryString) {
   string s = "key1=val1&key2=val2&key3=val3";
   Params dic;