From d752ba86c1872f64a4641cf77008826d32bde65f Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Wed, 8 Oct 2014 16:29:45 -0700
Subject: Add SCRIPT_VERIFY_SIGPUSHONLY (BIP62 rule 2)

---
 src/script/script.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'src/script/script.h')

diff --git a/src/script/script.h b/src/script/script.h
index d450db5ca..706a85a29 100644
--- a/src/script/script.h
+++ b/src/script/script.h
@@ -551,7 +551,7 @@ public:
 
     bool IsPayToScriptHash() const;
 
-    // Called by IsStandardTx and P2SH VerifyScript (which makes it consensus-critical).
+    // Called by IsStandardTx and P2SH/BIP62 VerifyScript (which makes it consensus-critical).
     bool IsPushOnly() const;
 
     // Called by IsStandardTx.
-- 
cgit v1.2.3


From 698c6abb25c1fbbc7fa4ba46b60e9f17d97332ef Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Wed, 8 Oct 2014 18:48:59 -0700
Subject: Add SCRIPT_VERIFY_MINIMALDATA (BIP62 rules 3 and 4)

Also use the new flag as a standard rule, and replace the IsCanonicalPush
standardness check with it (as it is more complete).
---
 src/script/script.h | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

(limited to 'src/script/script.h')

diff --git a/src/script/script.h b/src/script/script.h
index 706a85a29..e97967dce 100644
--- a/src/script/script.h
+++ b/src/script/script.h
@@ -192,10 +192,14 @@ public:
         m_value = n;
     }
 
-    explicit CScriptNum(const std::vector<unsigned char>& vch)
+    explicit CScriptNum(const std::vector<unsigned char>& vch, bool fRequireMinimal)
     {
-        if (vch.size() > nMaxNumSize)
-            throw scriptnum_error("CScriptNum(const std::vector<unsigned char>&) : overflow");
+        if (vch.size() > nMaxNumSize) {
+            throw scriptnum_error("script number overflow");
+        }
+        if (fRequireMinimal && vch.size() > 0 && (vch.back() & 0x7f) == 0 && (vch.size() <= 1 || (vch[vch.size() - 2] & 0x80) == 0)) {
+            throw scriptnum_error("non-minimally encoded script number");
+        }
         m_value = set_vch(vch);
     }
 
@@ -319,7 +323,6 @@ private:
     int64_t m_value;
 };
 
-
 /** Serialized script, used inside transaction inputs and outputs */
 class CScript : public std::vector<unsigned char>
 {
@@ -330,6 +333,10 @@ protected:
         {
             push_back(n + (OP_1 - 1));
         }
+        else if (n == 0)
+        {
+            push_back(OP_0);
+        }
         else
         {
             *this << CScriptNum::serialize(n);
@@ -554,9 +561,6 @@ public:
     // Called by IsStandardTx and P2SH/BIP62 VerifyScript (which makes it consensus-critical).
     bool IsPushOnly() const;
 
-    // Called by IsStandardTx.
-    bool HasCanonicalPushes() const;
-
     // Returns whether the script is guaranteed to fail at execution,
     // regardless of the initial stack. This allows outputs to be pruned
     // instantly when entering the UTXO set.
-- 
cgit v1.2.3


From 6004e77b926b5588e4b8eebdff843fe6652e5885 Mon Sep 17 00:00:00 2001
From: Peter Todd <pete@petertodd.org>
Date: Tue, 14 Oct 2014 11:18:24 -0400
Subject: Improve CScriptNum() comment

Edited-by: Pieter Wuille <pieter.wuille@gmail.com>
---
 src/script/script.h | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

(limited to 'src/script/script.h')

diff --git a/src/script/script.h b/src/script/script.h
index e97967dce..05f2e7e3a 100644
--- a/src/script/script.h
+++ b/src/script/script.h
@@ -197,8 +197,23 @@ public:
         if (vch.size() > nMaxNumSize) {
             throw scriptnum_error("script number overflow");
         }
-        if (fRequireMinimal && vch.size() > 0 && (vch.back() & 0x7f) == 0 && (vch.size() <= 1 || (vch[vch.size() - 2] & 0x80) == 0)) {
-            throw scriptnum_error("non-minimally encoded script number");
+        if (fRequireMinimal && vch.size() > 0) {
+            // Check that the number is encoded with the minimum possible
+            // number of bytes.
+            //
+            // If the most-significant-byte - excluding the sign bit - is zero
+            // then we're not minimal. Note how this test also rejects the
+            // negative-zero encoding, 0x80.
+            if ((vch.back() & 0x7f) == 0) {
+                // One exception: if there's more than one byte and the most
+                // significant bit of the second-most-significant-byte is set
+                // it would conflict with the sign bit. An example of this case
+                // is +-255, which encode to 0xff00 and 0xff80 respectively.
+                // (big-endian).
+                if (vch.size() <= 1 || (vch[vch.size() - 2] & 0x80) == 0) {
+                    throw scriptnum_error("non-minimally encoded script number");
+                }
+            }
         }
         m_value = set_vch(vch);
     }
-- 
cgit v1.2.3