From a1cb8ea96076c95ff5af844e1e9d983e060c30b2 Mon Sep 17 00:00:00 2001
From: Matthias Kruk <m@m10k.eu>
Date: Wed, 16 Jun 2021 08:23:55 +0900
Subject: [PATCH] include/ipc: Clean up ipc_msg API

The ipc module currently doesn't provide functions to get all fields
contained within a message. Further, signature-related functions don't
return an error if the message is invalid or the signature could not be
retrieved for another reason.
This commit adds the missing functions to the public API of the ipc
module and fixes the behavior of signature related functions so the
caller can correctly determine if an error has occurred.

The following functions have been added:
 - ipc_msg_get_version()
 - ipc_msg_get_signature()
 - ipc_msg_get_signer_name()
 - ipc_msg_get_signer_email()
 - ipc_msg_get_signer_key()
---
 include/ipc.sh | 137 ++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 102 insertions(+), 35 deletions(-)

diff --git a/include/ipc.sh b/include/ipc.sh
index c289a91..7e452bf 100644
--- a/include/ipc.sh
+++ b/include/ipc.sh
@@ -61,8 +61,13 @@ _ipc_msg_get_signature() {
 	local data
 	local signature
 
-	data=$(_ipc_msg_get "$msg" "data")
-	signature=$(_ipc_msg_get "$msg" "signature")
+	if ! data=$(_ipc_msg_get "$msg" "data"); then
+		return 2
+	fi
+
+	if ! signature=$(_ipc_msg_get "$msg" "signature"); then
+		return 2
+	fi
 
 	if ! gpg --verify <(base64 -d <<< "$signature") <(echo "$data") 2>&1; then
 		return 1
@@ -90,7 +95,7 @@ _ipc_msg_version_supported() {
 
 	local -i version
 
-	if ! version=$(_ipc_msg_get "$msg" "version"); then
+	if ! version=$(ipc_msg_get_version "$msg"); then
 		log_error "Could not get version from message"
 		return 1
 	fi
@@ -117,7 +122,7 @@ ipc_msg_validate() {
 	return 0
 }
 
-ipc_msg_get_signature_info() {
+_ipc_msg_get_signature_info() {
 	local msg="$1"
 
 	local signature
@@ -138,9 +143,18 @@ ipc_msg_get_signature_info() {
 	sig_email="(unknown)"
 	sig_key="(unknown)"
 
-	if signature=$(_ipc_msg_get_signature "$msg"); then
-		sig_valid="good"
-	fi
+	signature=$(_ipc_msg_get_signature "$msg")
+	case "$?" in
+		0)
+			sig_valid="good"
+			;;
+		1)
+			sig_valid="bad"
+			;;
+		*)
+			return 1
+			;;
+	esac
 
 	if [[ "$signature" =~ $sig_nameregex ]]; then
 		sig_name="${BASH_REMATCH[1]}"
@@ -155,26 +169,6 @@ ipc_msg_get_signature_info() {
 	return 0
 }
 
-ipc_msg_get_signing_key() {
-	local msg="$1"
-
-	local signature
-	local keyregex
-
-	keyregex='([0-9a-fA-F]{32,})'
-
-	if ! signature=$(_ipc_msg_get_signature "$msg"); then
-		return 1
-	fi
-
-	if [[ "$signature" =~ $keyregex ]]; then
-		echo "${BASH_REMATCH[1]}"
-		return 0
-	fi
-
-	return 1
-}
-
 ipc_msg_dump() {
 	local msg="$1"
 
@@ -256,6 +250,19 @@ _ipc_msg_new() {
 	return 0
 }
 
+ipc_msg_get_version() {
+	local msg="$1"
+
+	local version
+
+	if ! version=$(_ipc_msg_get "$msg" "version"); then
+		return 1
+	fi
+
+	echo "$version"
+	return 0
+}
+
 ipc_msg_get_source() {
 	local msg="$1"
 
@@ -282,6 +289,32 @@ ipc_msg_get_destination() {
 	return 0
 }
 
+ipc_msg_get_user() {
+	local msg="$1"
+
+	local user
+
+	if ! user=$(_ipc_msg_get "$msg" "user"); then
+		return 1
+	fi
+
+	echo "$user"
+	return 0
+}
+
+ipc_msg_get_timestamp() {
+	local msg="$1"
+
+	local timestamp
+
+	if ! timestamp=$(_ipc_msg_get "$msg" "timestamp"); then
+		return 1
+	fi
+
+	echo "$timestamp"
+	return 0
+}
+
 ipc_msg_get_data() {
 	local msg="$1"
 
@@ -300,29 +333,63 @@ ipc_msg_get_data() {
 	return 0
 }
 
-ipc_msg_get_user() {
+ipc_msg_get_signature() {
 	local msg="$1"
 
-	local user
+	local signature
 
-	if ! user=$(_ipc_msg_get "$msg" "user"); then
+	if ! signature=$(_ipc_msg_get "$msg" "signature"); then
 		return 1
 	fi
 
-	echo "$user"
+	echo "$signature"
 	return 0
 }
 
-ipc_msg_get_timestamp() {
+ipc_msg_get_signer_name() {
 	local msg="$1"
 
-	local timestamp
+	local info
+	local fields
 
-	if ! timestamp=$(_ipc_msg_get "$msg" "timestamp"); then
+	if ! info=$(_ipc_msg_get_signature_info "$msg"); then
 		return 1
 	fi
 
-	echo "$timestamp"
+	read -ra fields <<< "$info"
+	echo "${fields[@]:3}"
+	return 0
+}
+
+ipc_msg_get_signer_email() {
+	local msg="$1"
+
+	local info
+	local fields
+
+	if ! info=$(_ipc_msg_get_signature_info "$msg"); then
+		return 1
+	fi
+
+	read -ra fields <<< "$info"
+
+	echo "${fields[2]}"
+	return 0
+}
+
+ipc_msg_get_signer_key() {
+	local msg="$1"
+
+	local info
+	local fields
+
+	if ! info=$(_ipc_msg_get_signature_info "$msg"); then
+		return 1
+	fi
+
+	read -ra fields <<< "$info"
+
+	echo "${fields[1]}"
 	return 0
 }
 
-- 
2.47.3