crit: Print IP addresses in pretty mode

There are two places where we store IP addresses (both IPv4 and IPv6).
Mark them with custom option and print them in compressed form for
--pretty output.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Ruslan Kuprieiev <kupruser@gmail.com>

protobuf/opts.proto

@@ -2,6 +2,7 @@ import "google/protobuf/descriptor.proto";
 
 message CRIU_Opts {
 	optional bool hex = 1; // Idicate that CRIT should treat this field as hex.
+	optional bool ipadd = 2; // The field is IPv4/v6 address
 }
 
 extend google.protobuf.FieldOptions {

protobuf/sk-inet.proto

@@ -22,8 +22,8 @@ message inet_sk_entry {
 	required uint32			flags		=  9 [(criu).hex = true];
 	required uint32			backlog		= 10;
 
-	repeated uint32			src_addr	= 11;
-	repeated uint32			dst_addr	= 12;
+	repeated uint32			src_addr	= 11 [(criu).ipadd = true];
+	repeated uint32			dst_addr	= 12 [(criu).ipadd = true];
 
 	required fown_entry		fown		= 13;
 	required sk_opts_entry		opts		= 14;

pycriu/images/pb2dict.py

 from google.protobuf.descriptor import FieldDescriptor as FD
 import opts_pb2
+import ipaddr
+import socket
 
 # pb2dict and dict2pb are methods to convert pb to/from dict.
 # Inspired by:
@@ -43,6 +45,9 @@ _basic_cast = {
 def _marked_as_hex(field):
 	return field.GetOptions().Extensions[opts_pb2.criu].hex
 
+def _marked_as_ip(field):
+	return field.GetOptions().Extensions[opts_pb2.criu].ipadd
+
 def _pb2dict_cast(field, value, pretty = False, is_hex = False):
 	if not is_hex:
 		is_hex = _marked_as_hex(field)
@@ -73,6 +78,19 @@ def pb2dict(pb, pretty = False, is_hex = False):
 	for field, value in pb.ListFields():
 		if field.label == FD.LABEL_REPEATED:
 			d_val = []
+			if pretty and _marked_as_ip(field):
+				if len(value) == 1:
+					v = socket.ntohl(value[0])
+					addr = ipaddr.IPv4Address(v)
+				else:
+					v = 0 +	(socket.ntohl(value[0]) << (32 * 3)) + \
+						(socket.ntohl(value[1]) << (32 * 2)) + \
+						(socket.ntohl(value[2]) << (32 * 1)) + \
+						(socket.ntohl(value[3]))
+					addr = ipaddr.IPv6Address(v)
+
+				d_val.append(addr.compressed)
+			else:
 				for v in value:
 					d_val.append(_pb2dict_cast(field, v, pretty, is_hex))
 		else: