On Thu, Jan 30, 2025 at 06:52:52PM +0100, Pablo Neira Ayuso wrote:
> On Thu, Jan 30, 2025 at 06:49:41PM +0100, Pablo Neira Ayuso wrote:
> > Hi,
> >
> > On Thu, Jan 30, 2025 at 04:52:29PM +0300, Alexey Kashavkin wrote:
> > > Hello,
> > >
> > > I am still figuring out the syntax for adding rules to filter IP
> > > options. Please, if anyone has an understanding of how this works
> > > give at least a short reply.
> >
> > This 'type' field is redundant.
> >
> > > I understand how the exthdr expression works in the kernel code. But
> > > so far there is still a question about specifying the type field,
> > > what is the purpose of this field here? There is also a question
> > > about other fields, let's take for example the IP option LSRR, it
> > > has an addr field. I assume, knowing this option from RFC791 it
> > > specifies IP addresses, but in the case of nft it is not so, this
> > > field has datatype intereger.
> >
> > Yes, this should be at least 32-bits.
>
> Actually, this is 32-bits already:
>
> # nft describe ip option lsrr addr
> exthdr expression, datatype integer (integer), 32 bits
This is what you mean:
# nft describe ip option lsrr addr
exthdr expression, datatype ipv4_addr (IPv4 address) (basetype integer), 32 bits
diff --git a/src/ipopt.c b/src/ipopt.c
index 37f779d468ab..ddb42f5712d4 100644
--- a/src/ipopt.c
+++ b/src/ipopt.c
@@ -24,7 +24,7 @@ static const struct exthdr_desc ipopt_lsrr = {
[IPOPT_FIELD_TYPE] = PHT("type", 0, 8),
[IPOPT_FIELD_LENGTH] = PHT("length", 8, 8),
[IPOPT_FIELD_PTR] = PHT("ptr", 16, 8),
- [IPOPT_FIELD_ADDR_0] = PHT("addr", 24, 32),
+ [IPOPT_FIELD_ADDR_0] = PROTO_HDR_TEMPLATE("addr", &ipaddr_type, BYTEORDER_BIG_ENDIAN, 24, 32),
},
};
@@ -35,7 +35,7 @@ static const struct exthdr_desc ipopt_rr = {
[IPOPT_FIELD_TYPE] = PHT("type", 0, 8),
[IPOPT_FIELD_LENGTH] = PHT("length", 8, 8),
[IPOPT_FIELD_PTR] = PHT("ptr", 16, 8),
- [IPOPT_FIELD_ADDR_0] = PHT("addr", 24, 32),
+ [IPOPT_FIELD_ADDR_0] = PROTO_HDR_TEMPLATE("addr", &ipaddr_type, BYTEORDER_BIG_ENDIAN, 24, 32),
},
};
@@ -46,7 +46,7 @@ static const struct exthdr_desc ipopt_ssrr = {
[IPOPT_FIELD_TYPE] = PHT("type", 0, 8),
[IPOPT_FIELD_LENGTH] = PHT("length", 8, 8),
[IPOPT_FIELD_PTR] = PHT("ptr", 16, 8),
- [IPOPT_FIELD_ADDR_0] = PHT("addr", 24, 32),
+ [IPOPT_FIELD_ADDR_0] = PROTO_HDR_TEMPLATE("addr", &ipaddr_type, BYTEORDER_BIG_ENDIAN, 24, 32),
},
};
@@ -56,7 +56,7 @@ static const struct exthdr_desc ipopt_ra = {
.templates = {
[IPOPT_FIELD_TYPE] = PHT("type", 0, 8),
[IPOPT_FIELD_LENGTH] = PHT("length", 8, 8),
- [IPOPT_FIELD_VALUE] = PHT("value", 16, 16),
+ [IPOPT_FIELD_ADDR_0] = PROTO_HDR_TEMPLATE("addr", &ipaddr_type, BYTEORDER_BIG_ENDIAN, 24, 32),
},
};
