@@ -142,18 +142,27 @@ pub const Message = struct {
rtype: Type,
class: Class,
ttl: u32,
addr: Address,
data: RData,
pub fn init(fqdn: []const u8, addr: Address, ttl: u32) Resource {
pub const RData = union(enum) {
a: [4]u8,
aaaa: [16]u8,
cname: []const u8,
soa: struct {},
};
pub fn init(fqdn: []const u8, rdata: RData, ttl: u32) Resource {
return .{
.name = fqdn,
.rtype = switch (addr) {
.rtype = switch (rdata) {
.a => .a,
.aaaa => .aaaa,
.cname => .cname,
.soa => .soa,
},
.class = .in,
.ttl = ttl,
.addr = addr,
.data = rdata,
};
}
@@ -172,7 +181,7 @@ pub const Message = struct {
idx += 2;
try w.writeInt(u32, r.ttl, .big);
idx += 4;
switch (r.addr) {
switch (r.data) {
.a => |a| {
try w.writeInt(u16, 4, .big);
try w.writeAll(&a);
@@ -183,6 +192,10 @@ pub const Message = struct {
try w.writeAll(&aaaa);
idx += 18;
},
.cname => |name| {
idx += try Label.writeName(name, w);
},
.soa => unreachable,
}
return idx;
@@ -195,7 +208,7 @@ pub const Message = struct {
md, // obsolote -> mx
mf, // obsolote -> mx
cname,
sao,
soa,
mb,
mg,
mr,
@@ -269,30 +282,31 @@ pub const Message = struct {
for (0..payload_end) |payload_idx| {
if (payload_idx < msg.header.qdcount) {
const name = try Label.getName(name_buf, msg.bytes, &idx);
log.warn("label name {s}", .{name});
if (payload_idx == index) {
return .{ .question = .{
.name = name,
.qtype = @enumFromInt(@byteSwap(@as(u16, @bitCast(msg.bytes[idx..][0..2].*)))),
.class = @enumFromInt(@byteSwap(@as(u16, @bitCast(msg.bytes[idx..][2..4].*)))),
} };
} else {
idx += 4;
}
log.debug("label name {s}", .{name});
if (payload_idx == index) return .{ .question = .{
.name = name,
.qtype = @enumFromInt(@byteSwap(@as(u16, @bitCast(msg.bytes[idx..][0..2].*)))),
.class = @enumFromInt(@byteSwap(@as(u16, @bitCast(msg.bytes[idx..][2..4].*)))),
} };
idx += 4;
//log.warn("{any}", .{q.*});
} else if (payload_idx >= msg.header.qdcount) {
log.warn("answer {} {} {}", .{ idx, msg.bytes[idx], msg.bytes.len });
log.debug("answer {} {} {}", .{ idx, msg.bytes[idx], msg.bytes.len });
const name = try Label.getName(name_buf, msg.bytes, &idx);
log.warn("answer label {s}", .{name});
log.debug("answer label {s}", .{name});
const rdlen: u16 = @byteSwap(@as(u16, @bitCast(msg.bytes[idx..][8..10].*)));
if (rdlen > msg.bytes.len - idx) return error.InvalidPacket;
if (payload_idx != index) {
idx += rdlen;
idx += 10 + rdlen;
continue;
}
const rtype: Type = @enumFromInt(@byteSwap(@as(u16, @bitCast(msg.bytes[idx..][0..2].*))));
const addr: Address = switch (rtype) {
log.debug("answer type {}", .{rtype});
const addr: Resource.RData = switch (rtype) {
.a => .{ .a = msg.bytes[idx..][10..][0..4].* },
.aaaa => .{ .aaaa = msg.bytes[idx..][10..][0..16].* },
.cname => .{ .cname = msg.bytes[idx..][10..][0..rdlen] },
.soa => undefined,
else => return error.ResponseTypeNotImplemented,
};
@@ -301,7 +315,7 @@ pub const Message = struct {
.rtype = rtype,
.class = @enumFromInt(@byteSwap(@as(u16, @bitCast(msg.bytes[idx..][2..4].*)))),
.ttl = @byteSwap(@as(u32, @bitCast(msg.bytes[idx..][4..8].*))),
.addr = addr,
.data = addr,
};
return .{ .answer = r };
@@ -340,7 +354,7 @@ pub const Message = struct {
return msg;
}
pub fn answer(id: u16, fqdns: []const []const u8, ips: []const Address, bytes: []u8) !Message {
pub fn answer(id: u16, fqdns: []const []const u8, ips: []const Resource.RData, bytes: []u8) !Message {
var h: Header = .{
.id = id,
.qr = true,
@@ -382,7 +396,7 @@ pub const Message = struct {
}
pub fn answerDrop(id: u16, fqdn: []const u8, bytes: []u8) !Message {
const addrs: [16]Address = @splat(Address{ .a = @splat(0) });
const addrs: [16]Resource.RData = @splat(Resource.RData{ .a = @splat(0) });
return try answer(id, &[1][]const u8{fqdn}, addrs[0..1], bytes);
}
@@ -446,10 +460,10 @@ pub const Label = struct {
continue :sw bytes[idx];
},
192...255 => |b| {
if (!pointered) index.* = idx + 2;
pointered = true;
idx += 2;
if (idx >= bytes.len) return error.InvalidLabel;
index.* = idx;
const offset: u16 = @as(u16, b & 0b111111) << 8 | bytes[idx - 1];
if (offset < 12 or offset >= bytes.len) return error.InvalidLabel;
idx = offset;
@@ -493,11 +507,6 @@ pub const Label = struct {
}
};
pub const Address = union(enum) {
a: [4]u8,
aaaa: [16]u8,
};
test "Message.Header" {
const thing: Message.Header = .{
.id = 16,
@@ -556,7 +565,7 @@ test "build answer" {
const msg0 = try Message.answer(
31337,
&[1][]const u8{"gr.ht."},
&[1]Address{.{ .a = .{ 127, 4, 20, 69 } }},
&[1]Message.Resource.RData{.{ .a = .{ 127, 4, 20, 69 } }},
&buffer,
);
@@ -572,7 +581,7 @@ test "build answer" {
const msg1 = try Message.answer(
31337,
&[1][]const u8{"gr.ht"},
&[1]Address{.{ .a = .{ 127, 4, 20, 69 } }},
&[1]Message.Resource.RData{.{ .a = .{ 127, 4, 20, 69 } }},
&buffer,
);
@@ -590,7 +599,7 @@ test "build answer" {
const msg2 = try Message.answer(
31337,
&[1][]const u8{"gr.ht."},
&[1]Address{.{ .a = .{ 127, 4, 20, 69 } }},
&[1]Message.Resource.RData{.{ .a = .{ 127, 4, 20, 69 } }},
&big_buffer,
);
try std.testing.expectEqualSlices(u8, &[_]u8{
@@ -602,27 +611,68 @@ test "build answer" {
}
test "response iter" {
const base = [_]u8{
197, 22, 129, 128, 0, 1, 0, 1, 0, 0, 0, 0,
7, 122, 105, 103, 108, 97, 110, 103, 3, 111, 114, 103,
0, 0, 28, 0, 1, 192, 12, 0, 28, 0, 1, 0,
0, 1, 44, 0, 16, 42, 1, 4, 249, 48, 81, 75,
210, 0, 0, 0, 0, 0, 0, 0, 2,
};
const msg: Message = try .fromBytes(&base);
var it = msg.iterator();
try std.testing.expectEqual(msg.header.qdcount, 1);
try std.testing.expectEqual(msg.header.ancount, 1);
var count: usize = 2;
while (try it.next()) |r| {
switch (r) {
.question => try std.testing.expectEqual(count, 2),
.answer => try std.testing.expectEqual(count, 1),
{
const base = [_]u8{
197, 22, 129, 128, 0, 1, 0, 1, 0, 0, 0, 0,
7, 122, 105, 103, 108, 97, 110, 103, 3, 111, 114, 103,
0, 0, 28, 0, 1, 192, 12, 0, 28, 0, 1, 0,
0, 1, 44, 0, 16, 42, 1, 4, 249, 48, 81, 75,
210, 0, 0, 0, 0, 0, 0, 0, 2,
};
const msg: Message = try .fromBytes(&base);
var it = msg.iterator();
try std.testing.expectEqual(msg.header.qdcount, 1);
try std.testing.expectEqual(msg.header.ancount, 1);
var count: usize = 2;
while (try it.next()) |r| {
switch (r) {
.question => try std.testing.expectEqual(count, 2),
.answer => try std.testing.expectEqual(count, 1),
}
count -%= 1;
}
count -%= 1;
}
try std.testing.expectEqual(count, 0);
try std.testing.expectEqual(count, 0);
}
{
const base = [_]u8{
242, 38, 129, 128, 0, 1, 0, 4, 0, 1, 0, 0, 3,
110, 110, 110, 9, 110, 100, 110, 110, 101, 110, 101, 110, 110,
3, 99, 110, 109, 0, 0, 28, 0, 1, 192, 12, 0, 5,
0, 1, 0, 0, 11, 214, 0, 25, 17, 110, 110, 110, 45,
110, 105, 110, 110, 101, 110, 101, 110, 110, 45, 99, 110, 109,
4, 103, 110, 108, 98, 192, 16, 192, 47, 0, 5, 0, 1,
0, 0, 11, 214, 0, 32, 14, 50, 45, 48, 49, 45, 51,
55, 45, 50, 45, 45, 45, 49, 56, 3, 99, 100, 120, 7,
99, 45, 45, 45, 45, 105, 110, 3, 110, 101, 110, 0, 192,
84, 0, 5, 0, 1, 0, 0, 0, 32, 0, 28, 3, 110,
110, 110, 9, 110, 105, 110, 110, 101, 110, 100, 110, 110, 3,
99, 110, 100, 7, 100, 100, 100, 100, 100, 100, 120, 192, 111,
192, 128, 0, 5, 0, 1, 0, 0, 83, 84, 0, 21, 5,
101, 54, 52, 52, 57, 1, 97, 10, 97, 107, 97, 109, 97,
105, 101, 100, 103, 101, 192, 111, 192, 174, 0, 6, 0, 1,
0, 0, 2, 220, 0, 46, 3, 110, 48, 97, 192, 176, 10,
104, 110, 110, 110, 109, 97, 110, 110, 101, 110, 6, 97, 107,
97, 109, 97, 105, 192, 26, 103, 212, 110, 234, 0, 0, 3,
232, 0, 0, 3, 232, 0, 0, 3, 232, 0, 0, 7, 8,
};
const msg: Message = try .fromBytes(&base);
var it = msg.iterator();
try std.testing.expectEqual(msg.header.qdcount, 1);
try std.testing.expectEqual(msg.header.ancount, 4);
try std.testing.expectEqual(msg.header.arcount, 0);
try std.testing.expectEqual(msg.header.nscount, 1);
var count: usize = 6;
while (try it.next()) |r| {
switch (r) {
.question => try std.testing.expectEqual(count, 6),
.answer => try std.testing.expect(count <= 5),
}
count -%= 1;
}
try std.testing.expectEqual(count, 0);
}
}
test "build answerDrop" {