1 files changed, 25 insertions, 0 deletions
diff --git a/src/script/script.cpp b/src/script/script.cpp
index 9a6419088b..88b4bc2f44 100644
--- a/src/script/script.cpp
+++ b/src/script/script.cpp
@@ -339,3 +339,28 @@ bool IsOpSuccess(const opcodetype& opcode)
            (opcode >= 141 && opcode <= 142) || (opcode >= 149 && opcode <= 153) ||
            (opcode >= 187 && opcode <= 254);
 }
+
+bool CheckMinimalPush(const std::vector<unsigned char>& data, opcodetype opcode) {
+    // Excludes OP_1NEGATE, OP_1-16 since they are by definition minimal
+    assert(0 <= opcode && opcode <= OP_PUSHDATA4);
+    if (data.size() == 0) {
+        // Should have used OP_0.
+        return opcode == OP_0;
+    } else if (data.size() == 1 && data[0] >= 1 && data[0] <= 16) {
+        // Should have used OP_1 .. OP_16.
+        return false;
+    } else if (data.size() == 1 && data[0] == 0x81) {
+        // Should have used OP_1NEGATE.
+        return false;
+    } else if (data.size() <= 75) {
+        // Must have used a direct push (opcode indicating number of bytes pushed + those bytes).
+        return opcode == data.size();
+    } else if (data.size() <= 255) {
+        // Must have used OP_PUSHDATA.
+        return opcode == OP_PUSHDATA1;
+    } else if (data.size() <= 65535) {
+        // Must have used OP_PUSHDATA2.
+        return opcode == OP_PUSHDATA2;
+    }
+    return true;
+}