From 43530c8837857026a6a90d29e1ac7ea83be5665e Mon Sep 17 00:00:00 2001
From: Peter Todd <pete@petertodd.org>
Date: Fri, 18 Mar 2016 06:28:36 -0400
Subject: [PATCH] Add verify-commits from Bitcoin Core

---
 contrib/verify-commits/allow-revsig-commits |  0
 contrib/verify-commits/gpg.sh               | 33 +++++++++++
 contrib/verify-commits/pre-push-hook.sh     | 16 ++++++
 contrib/verify-commits/trusted-git-root     |  1 +
 contrib/verify-commits/trusted-keys         |  3 +
 contrib/verify-commits/verify-commits.sh    | 61 +++++++++++++++++++++
 6 files changed, 114 insertions(+)
 create mode 100644 contrib/verify-commits/allow-revsig-commits
 create mode 100755 contrib/verify-commits/gpg.sh
 create mode 100755 contrib/verify-commits/pre-push-hook.sh
 create mode 100644 contrib/verify-commits/trusted-git-root
 create mode 100644 contrib/verify-commits/trusted-keys
 create mode 100755 contrib/verify-commits/verify-commits.sh

diff --git a/contrib/verify-commits/allow-revsig-commits b/contrib/verify-commits/allow-revsig-commits
new file mode 100644
index 00000000..e69de29b
diff --git a/contrib/verify-commits/gpg.sh b/contrib/verify-commits/gpg.sh
new file mode 100755
index 00000000..f84c9a8c
--- /dev/null
+++ b/contrib/verify-commits/gpg.sh
@@ -0,0 +1,33 @@
+#!/bin/bash
+INPUT=$(</dev/stdin)
+VALID=false
+REVSIG=false
+IFS=$'\n'
+for LINE in $(echo "$INPUT" | gpg --trust-model always "$@" 2>/dev/null); do
+	case "$LINE" in
+	"[GNUPG:] VALIDSIG "*)
+		while read KEY; do
+			case "$LINE" in "[GNUPG:] VALIDSIG $KEY "*) VALID=true;; esac
+		done < ./contrib/verify-commits/trusted-keys
+		;;
+	"[GNUPG:] REVKEYSIG "*)
+		[ "$BITCOIN_VERIFY_COMMITS_ALLOW_REVSIG" != 1 ] && exit 1
+		while read KEY; do
+			case "$LINE" in "[GNUPG:] REVKEYSIG ${KEY:24:40} "*)
+				REVSIG=true
+				GOODREVSIG="[GNUPG:] GOODSIG ${KEY:24:40} "
+				;;
+			esac
+		done < ./contrib/verify-commits/trusted-keys
+		;;
+	esac
+done
+if ! $VALID; then
+	exit 1
+fi
+if $VALID && $REVSIG; then
+	echo "$INPUT" | gpg --trust-model always "$@" | grep "\[GNUPG:\] \(NEWSIG\|SIG_ID\|VALIDSIG\)" 2>/dev/null
+	echo "$GOODREVSIG"
+else
+	echo "$INPUT" | gpg --trust-model always "$@" 2>/dev/null
+fi
diff --git a/contrib/verify-commits/pre-push-hook.sh b/contrib/verify-commits/pre-push-hook.sh
new file mode 100755
index 00000000..d52f5756
--- /dev/null
+++ b/contrib/verify-commits/pre-push-hook.sh
@@ -0,0 +1,16 @@
+#!/bin/bash
+if ! [[ "$2" =~ ^(git@)?(www.)?github.com(:|/)petertodd/python-bitcoinlib(.git)?$ ]]; then
+    exit 0
+fi
+
+while read LINE; do
+    set -- A $LINE
+    if [ "$4" != "refs/heads/master" ]; then
+        continue
+    fi
+    if ! ./contrib/verify-commits/verify-commits.sh $3 > /dev/null 2>&1; then
+        echo "ERROR: A commit is not signed, can't push"
+        ./contrib/verify-commits/verify-commits.sh
+        exit 1
+    fi
+done < /dev/stdin
diff --git a/contrib/verify-commits/trusted-git-root b/contrib/verify-commits/trusted-git-root
new file mode 100644
index 00000000..376255a3
--- /dev/null
+++ b/contrib/verify-commits/trusted-git-root
@@ -0,0 +1 @@
+22cc8167a98ea026b6a4fe16aa2adc2de17aa97f
diff --git a/contrib/verify-commits/trusted-keys b/contrib/verify-commits/trusted-keys
new file mode 100644
index 00000000..802ee5b3
--- /dev/null
+++ b/contrib/verify-commits/trusted-keys
@@ -0,0 +1,3 @@
+15CC9446387233AF0104F6132481403DA5F091FB
+C5DDF20211D8F6E5F6E010F8C085F21CE7F4B9DC
+14FCC76E05E775AAE61ABEFF9EC4568398C13B16
diff --git a/contrib/verify-commits/verify-commits.sh b/contrib/verify-commits/verify-commits.sh
new file mode 100755
index 00000000..c0ebeaeb
--- /dev/null
+++ b/contrib/verify-commits/verify-commits.sh
@@ -0,0 +1,61 @@
+#!/bin/bash
+
+REALPATH=$(realpath "$0")
+DIR=$(dirname "$REALPATH")
+
+VERIFIED_ROOT=$(cat "${DIR}/trusted-git-root")
+
+IS_REVSIG_ALLOWED () {
+	while read LINE; do
+		[ "$LINE" = "$1" ] && return 0
+	done < "${DIR}/allow-revsig-commits"
+	return 1
+}
+
+HAVE_FAILED=false
+IS_SIGNED () {
+	if [ $1 = $VERIFIED_ROOT ]; then
+		return 0;
+	fi
+	if IS_REVSIG_ALLOWED "$1"; then
+		export BITCOIN_VERIFY_COMMITS_ALLOW_REVSIG=1
+	else
+		export BITCOIN_VERIFY_COMMITS_ALLOW_REVSIG=0
+	fi
+	if ! git -c "gpg.program=${DIR}/gpg.sh" verify-commit $1 > /dev/null 2>&1; then
+		return 1;
+	fi
+	local PARENTS=$(git show -s --format=format:%P $1)
+	for PARENT in $PARENTS; do
+		if IS_SIGNED $PARENT > /dev/null; then
+			return 0;
+		fi
+	done
+	if ! "$HAVE_FAILED"; then
+		echo "No parent of $1 was signed with a trusted key!" > /dev/stderr
+		echo "Parents are:" > /dev/stderr
+		for PARENT in $PARENTS; do
+			git show -s $PARENT > /dev/stderr
+		done
+		HAVE_FAILED=true
+	fi
+	return 1;
+}
+
+if [ x"$1" = "x" ]; then
+	TEST_COMMIT="HEAD"
+else
+	TEST_COMMIT="$1"
+fi
+
+IS_SIGNED "$TEST_COMMIT"
+RES=$?
+if [ "$RES" = 1 ]; then
+	if ! "$HAVE_FAILED"; then
+		echo "$TEST_COMMIT was not signed with a trusted key!"
+	fi
+else
+	echo "There is a valid path from $TEST_COMMIT to $VERIFIED_ROOT where all commits are signed!"
+fi
+
+exit $RES