On Mon, Dec 2, 2024 at 6:27 AM Christian Göttsche
<cgoettsche@xxxxxxxxxxxxx> wrote:
>
> From: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
>
> Drop the host bits in the IPV6 address defined via a CIDR notation in
> define_ipv6_cidr_node_context(), similar to
> define_ipv4_cidr_node_context(). Otherwise the kernel will never match
> this entry since the host bits from the actual address will be zeroed
> before comparison, see
> security/selinux/ss/services.c:match_ipv6_addrmask().
>
> Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
Acked-by: James Carter <jwcart2@xxxxxxxxx>
> ---
> Note the traditional address+mask syntax does not drop the host bits as
> well, so they are also dead entries, but I refrained from changing
> this legacy behavior (the CIDR support is new) and checkpolicy nowadays
> also warns about host bits set (and fails with the option `-E`).
> ---
> checkpolicy/policy_define.c | 9 +++++++++
> checkpolicy/tests/policy_allonce.conf | 5 ++++-
> checkpolicy/tests/policy_allonce.expected.conf | 3 +++
> checkpolicy/tests/policy_allonce.expected_opt.conf | 3 +++
> 4 files changed, 19 insertions(+), 1 deletion(-)
>
> diff --git a/checkpolicy/policy_define.c b/checkpolicy/policy_define.c
> index 4b0eca6b..2f811b67 100644
> --- a/checkpolicy/policy_define.c
> +++ b/checkpolicy/policy_define.c
> @@ -5709,6 +5709,14 @@ static void ipv6_cidr_bits_to_mask(unsigned long cidr_bits, struct in6_addr *mas
> }
> }
>
> +static void ipv6_apply_mask(struct in6_addr *restrict addr, const struct in6_addr *restrict mask)
> +{
> + unsigned i;
> +
> + for (i = 0; i < 4; i++)
> + addr->s6_addr32[i] &= mask->s6_addr32[i];
> +}
> +
> static int insert_ipv6_node(ocontext_t *newc)
> {
> ocontext_t *c, *l;
> @@ -5884,6 +5892,7 @@ int define_ipv6_cidr_node_context(void)
> return -1;
> }
>
> + ipv6_apply_mask(&addr, &mask);
> memcpy(&newc->u.node6.addr[0], &addr.s6_addr[0], 16);
> memcpy(&newc->u.node6.mask[0], &mask.s6_addr[0], 16);
>
> diff --git a/checkpolicy/tests/policy_allonce.conf b/checkpolicy/tests/policy_allonce.conf
> index 51a8c40a..95a0f265 100644
> --- a/checkpolicy/tests/policy_allonce.conf
> +++ b/checkpolicy/tests/policy_allonce.conf
> @@ -76,9 +76,12 @@ portcon tcp 80 USER1:ROLE1:TYPE1
> portcon udp 100-200 USER1:ROLE1:TYPE1
> netifcon lo USER1:ROLE1:TYPE1 USER1:ROLE1:TYPE1
> nodecon 127.0.0.1 255.255.255.255 USER1:ROLE1:TYPE1
> -nodecon 127.0.0.0/24 USER1:ROLE1:TYPE1
> +nodecon 192.168.42.0 255.255.0.0 USER1:ROLE1:TYPE1
> +nodecon 127.0.0.1/24 USER1:ROLE1:TYPE1
> +nodecon 192.168.41.0/16 USER1:ROLE1:TYPE1
> nodecon ::ffff:127.0.0.1 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff USER1:ROLE1:TYPE1
> nodecon ff80::/16 USER1:ROLE1:TYPE1
> +nodecon ff00::1/8 USER1:ROLE1:TYPE1
> # hex numbers will be turned in decimal ones
> ibpkeycon fe80:: 0xFFFF USER1:ROLE1:TYPE1
> ibpkeycon fe80:: 0-0x10 USER1:ROLE1:TYPE1
> diff --git a/checkpolicy/tests/policy_allonce.expected.conf b/checkpolicy/tests/policy_allonce.expected.conf
> index 355d9991..79d62319 100644
> --- a/checkpolicy/tests/policy_allonce.expected.conf
> +++ b/checkpolicy/tests/policy_allonce.expected.conf
> @@ -82,8 +82,11 @@ portcon udp 100-200 USER1:ROLE1:TYPE1
> netifcon lo USER1:ROLE1:TYPE1 USER1:ROLE1:TYPE1
> nodecon 127.0.0.1 255.255.255.255 USER1:ROLE1:TYPE1
> nodecon 127.0.0.0 255.255.255.0 USER1:ROLE1:TYPE1
> +nodecon 192.168.0.0 255.255.0.0 USER1:ROLE1:TYPE1
> +nodecon 192.168.42.0 255.255.0.0 USER1:ROLE1:TYPE1
> nodecon ::ffff:127.0.0.1 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff USER1:ROLE1:TYPE1
> nodecon ff80:: ffff:: USER1:ROLE1:TYPE1
> +nodecon ff00:: ff00:: USER1:ROLE1:TYPE1
> ibpkeycon fe80:: 65535 USER1:ROLE1:TYPE1
> ibpkeycon fe80:: 0-16 USER1:ROLE1:TYPE1
> ibendportcon mlx4_0 2 USER1:ROLE1:TYPE1
> diff --git a/checkpolicy/tests/policy_allonce.expected_opt.conf b/checkpolicy/tests/policy_allonce.expected_opt.conf
> index 74eec4ba..fa4e319b 100644
> --- a/checkpolicy/tests/policy_allonce.expected_opt.conf
> +++ b/checkpolicy/tests/policy_allonce.expected_opt.conf
> @@ -82,8 +82,11 @@ portcon udp 100-200 USER1:ROLE1:TYPE1
> netifcon lo USER1:ROLE1:TYPE1 USER1:ROLE1:TYPE1
> nodecon 127.0.0.1 255.255.255.255 USER1:ROLE1:TYPE1
> nodecon 127.0.0.0 255.255.255.0 USER1:ROLE1:TYPE1
> +nodecon 192.168.0.0 255.255.0.0 USER1:ROLE1:TYPE1
> +nodecon 192.168.42.0 255.255.0.0 USER1:ROLE1:TYPE1
> nodecon ::ffff:127.0.0.1 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff USER1:ROLE1:TYPE1
> nodecon ff80:: ffff:: USER1:ROLE1:TYPE1
> +nodecon ff00:: ff00:: USER1:ROLE1:TYPE1
> ibpkeycon fe80:: 65535 USER1:ROLE1:TYPE1
> ibpkeycon fe80:: 0-16 USER1:ROLE1:TYPE1
> ibendportcon mlx4_0 2 USER1:ROLE1:TYPE1
> --
> 2.45.2
>
>
