APL: adjust error handling and tests (#1302)

This commit is contained in:
Tom Sellers 2021-10-12 06:06:29 -05:00 committed by GitHub
parent 1630ffe2ca
commit 7318b01e11
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 26 additions and 16 deletions

View File

@ -781,6 +781,8 @@ func unpackDataAplPrefix(msg []byte, off int) (APLPrefix, int, error) {
if off+afdlen > len(msg) {
return APLPrefix{}, len(msg), &Error{err: "overflow unpacking APL address"}
}
// Address MUST NOT contain trailing zero bytes per RFC3123 Sections 4.1 and 4.2.
off += copy(ip, msg[off:off+afdlen])
if afdlen > 0 {
last := ip[afdlen-1]
@ -792,10 +794,6 @@ func unpackDataAplPrefix(msg []byte, off int) (APLPrefix, int, error) {
IP: ip,
Mask: net.CIDRMask(int(prefix), 8*len(ip)),
}
network := ipnet.IP.Mask(ipnet.Mask)
if !network.Equal(ipnet.IP) {
return APLPrefix{}, len(msg), &Error{err: "invalid APL address length"}
}
return APLPrefix{
Negation: (nlen & 0x80) != 0,

View File

@ -391,34 +391,42 @@ func TestUnpackDataAplPrefix_Errors(t *testing.T) {
tests := []struct {
name string
wire []byte
want string
}{
{
"incomplete header",
[]byte{0x00, 0x01, 0x18},
"dns: overflow unpacking APL prefix",
},
{
"unrecognized family",
[]byte{0x00, 0x03, 0x00, 0x00},
"dns: unrecognized APL address family",
},
{
"prefix length exceeded",
"prefix too large for family IPv4",
[]byte{0x00, 0x01, 0x21, 0x04, 192, 0, 2, 0},
"dns: APL prefix too long",
},
{
"address with extra byte",
[]byte{0x00, 0x01, 0x10, 0x03, 192, 0, 2},
"prefix too large for family IPv6",
[]byte{0x00, 0x02, 0x81, 0x85, 0x20, 0x01, 0x0d, 0xb8, 0x80},
"dns: APL prefix too long",
},
{
"incomplete buffer",
[]byte{0x00, 0x01, 0x10, 0x02, 192},
},
{
"extra bits set",
[]byte{0x00, 0x01, 22, 0x03, 192, 0, 2},
},
{
"afdlen invalid",
"afdlen too long for address family IPv4",
[]byte{0x00, 0x01, 22, 0x05, 192, 0, 2, 0, 0},
"dns: APL length too long",
},
{
"overflow unpacking APL address",
[]byte{0x00, 0x01, 0x10, 0x02, 192},
"dns: overflow unpacking APL address",
},
{
"address included trailing zeros",
[]byte{0x00, 0x01, 0x10, 0x04, 192, 0, 2, 0},
"dns: extra APL address bits",
},
}
for _, tt := range tests {
@ -427,6 +435,10 @@ func TestUnpackDataAplPrefix_Errors(t *testing.T) {
if err == nil {
t.Fatal("expected error, got none")
}
if err.Error() != tt.want {
t.Errorf("expected %s, got %s", tt.want, err.Error())
}
})
}
}