From 1f7c32194065f4627bc1c20f1c3bc598ab310e01 Mon Sep 17 00:00:00 2001
From: Terrence Asselin <terrence.asselin@lexisnexisrisk.com>
Date: Fri, 6 Dec 2024 14:47:18 -0600
Subject: [PATCH] HPCC-32999 Sanitize user provided password to ZAP file

- Single-quote the entire password to preserve all characters but prevent
  interpretation as metacharacters.
- Replace any single quote in the original string with a sequence of characters
  that breaks the single-quoted password into three parts
    (1) a single-quoted prefix
    (2) a double-quoted single quote and
    (3) a single-quoted suffix
- The shell quote-removal deletes double-quotes around any single quote at the
  same time that it de-quotes the single-quoted prefix and suffix, leaving any
  single quote inside the password string that is tokenized as a single
  argument.

This will require a different approach for Windows targets as a future task.

Signed-off-by: Terrence Asselin <terrence.asselin@lexisnexisrisk.com>
---
 .../ws_workunits/ws_workunitsHelpers.cpp      |  6 +++-
 system/jlib/jstring.cpp                       | 29 +++++++++++++++++++
 system/jlib/jstring.hpp                       |  3 ++
 3 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/esp/services/ws_workunits/ws_workunitsHelpers.cpp b/esp/services/ws_workunits/ws_workunitsHelpers.cpp
index a018886f466..37a5efb8c3e 100644
--- a/esp/services/ws_workunits/ws_workunitsHelpers.cpp
+++ b/esp/services/ws_workunits/ws_workunitsHelpers.cpp
@@ -4486,7 +4486,11 @@ void CWsWuFileHelper::zipZAPFiles(const char* parentFolder, const char* zapFiles
     else
         zipCommand.setf("cd %s\nzip -r", parentFolder);
     if (!isEmptyString(passwordReq))
-        zipCommand.append(" --password ").append(passwordReq);
+    {
+        StringBuffer sanitizedPassword;
+        sanitizeCommandArg(passwordReq, sanitizedPassword);
+        zipCommand.append(" --password ").append(sanitizedPassword);
+    }
     zipCommand.append(" ").append(zipFileNameWithFullPath).append(" ").append(zapFiles);
     int zipRet = system(zipCommand);
     if (zipRet != 0)
diff --git a/system/jlib/jstring.cpp b/system/jlib/jstring.cpp
index 7e581f2503a..1f6492b4bef 100644
--- a/system/jlib/jstring.cpp
+++ b/system/jlib/jstring.cpp
@@ -2983,3 +2983,32 @@ const void * jmemmem(size_t lenHaystack, const void * haystack, size_t lenNeedle
 
     return nullptr;
 }
+
+/**
+ * For preventing command injection, sanitize the argument to be passed to the system command.
+ * - Quote the entire argument with single quotes to prevent interpretation of shell metacharacters.
+ * - Since a single-quoted string can't contain single quotes, even escaped, replace each single
+ *   quote in the argument with the sequence '"'"' . That closes the single quoted string, appends
+ *   a literal single quote, and reopens the single quoted string
+ */
+StringBuffer& sanitizeCommandArg(const char* arg, StringBuffer& sanitized)
+{
+#if defined(__linux__) || defined(__APPLE__)
+    if (!isEmptyString(arg))
+    {
+        size_t len = strlen(arg);
+        sanitized.append('\'');
+        for (size_t i = 0; i < len; i++)
+        {
+            if (arg[i] == '\'')
+                sanitized.append(R"('"'"')");
+            else
+                sanitized.append(arg[i]);
+        }
+        sanitized.append('\'');
+    }
+#else
+    sanitized.append(arg);
+#endif
+    return sanitized;
+}
diff --git a/system/jlib/jstring.hpp b/system/jlib/jstring.hpp
index d61b7fb7a1f..f1ece8d0caa 100644
--- a/system/jlib/jstring.hpp
+++ b/system/jlib/jstring.hpp
@@ -659,4 +659,7 @@ extern jlib_decl void ensureSeparator(StringBuffer & out, char separator);
 //Search for one block of bytes within another block of bytes - memmem is not standard, so we provide our own
 extern jlib_decl const void * jmemmem(size_t lenHaystack, const void * haystack, size_t lenNeedle, const void *needle);
 
+// For preventing command injection, sanitize the argument to be passed to the system command
+extern jlib_decl StringBuffer& sanitizeCommandArg(const char* arg, StringBuffer& sanitized);
+
 #endif