1 files changed, 59 insertions, 0 deletions
diff --git a/contrib/verify-commits/gpg.sh b/contrib/verify-commits/gpg.sh
new file mode 100755
index 0000000000..b01e2a6d39
--- /dev/null
+++ b/contrib/verify-commits/gpg.sh
@@ -0,0 +1,59 @@
+#!/bin/sh
+# Copyright (c) 2014-2016 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+INPUT=$(cat /dev/stdin)
+VALID=false
+REVSIG=false
+IFS='
+'
+if [ "$BITCOIN_VERIFY_COMMITS_ALLOW_SHA1" = 1 ]; then
+	GPG_RES="$(echo "$INPUT" | gpg --trust-model always "$@" 2>/dev/null)"
+else
+	# Note how we've disabled SHA1 with the --weak-digest option, disabling
+	# signatures - including selfsigs - that use SHA1. While you might think that
+	# collision attacks shouldn't be an issue as they'd be an attack on yourself,
+	# in fact because what's being signed is a commit object that's
+	# semi-deterministically generated by untrusted input (the pull-req) in theory
+	# an attacker could construct a pull-req that results in a commit object that
+	# they've created a collision for. Not the most likely attack, but preventing
+	# it is pretty easy so we do so as a "belt-and-suspenders" measure.
+	GPG_RES=""
+	for LINE in "$(gpg --version)"; do
+		case "$LINE" in
+			"gpg (GnuPG) 1.4.1"*|"gpg (GnuPG) 2.0."*)
+				echo "Please upgrade to at least gpg 2.1.10 to check for weak signatures" > /dev/stderr
+				GPG_RES="$(echo "$INPUT" | gpg --trust-model always "$@" 2>/dev/null)"
+				;;
+			# We assume if you're running 2.1+, you're probably running 2.1.10+
+			# gpg will fail otherwise
+			# We assume if you're running 1.X, it is either 1.4.1X or 1.4.20+
+			# gpg will fail otherwise
+		esac
+	done
+	[ "$GPG_RES" = "" ] && GPG_RES="$(echo "$INPUT" | gpg --trust-model always --weak-digest sha1 "$@" 2>/dev/null)"
+fi
+for LINE in $(echo "$GPG_RES"); do
+	case "$LINE" in
+	"[GNUPG:] VALIDSIG "*)
+		while read KEY; do
+			[ "${LINE#?GNUPG:? VALIDSIG * * * * * * * * * }" = "$KEY" ] && VALID=true
+		done < ./contrib/verify-commits/trusted-keys
+		;;
+	"[GNUPG:] REVKEYSIG "*)
+		[ "$BITCOIN_VERIFY_COMMITS_ALLOW_REVSIG" != 1 ] && exit 1
+		REVSIG=true
+		GOODREVSIG="[GNUPG:] GOODSIG ${LINE#* * *}"
+		;;
+	esac
+done
+if ! $VALID; then
+	exit 1
+fi
+if $VALID && $REVSIG; then
+	echo "$INPUT" | gpg --trust-model always "$@" 2>/dev/null | grep "\[GNUPG:\] \(NEWSIG\|SIG_ID\|VALIDSIG\)"
+	echo "$GOODREVSIG"
+else
+	echo "$INPUT" | gpg --trust-model always "$@" 2>/dev/null
+fi