> On 22 Jan 2020, at 8:54 am, Damien Miller <d...@mindrot.org> wrote:
>
> On Wed, 22 Jan 2020, David Gwynne wrote:
>
>>> Index: sys/kern/kern_pledge.c
>>> ===================================================================
>>> RCS file: /cvs/src/sys/kern/kern_pledge.c,v
>>> retrieving revision 1.255
>>> diff -u -p -r1.255 kern_pledge.c
>>> --- sys/kern/kern_pledge.c 25 Aug 2019 18:46:40 -0000 1.255
>>> +++ sys/kern/kern_pledge.c 29 Oct 2019 07:57:58 -0000
>>> @@ -666,7 +666,7 @@ pledge_namei(struct proc *p, struct name
>>> }
>>> }
>>>
>>> - /* DNS needs /etc/{resolv.conf,hosts,services}. */
>>> + /* DNS needs /etc/{resolv.conf,hosts,services,protocols}. */
>>> if ((ni->ni_pledge == PLEDGE_RPATH) &&
>>> (p->p_p->ps_pledge & PLEDGE_DNS)) {
>>> if (strcmp(path, "/etc/resolv.conf") == 0) {
>>> @@ -678,6 +678,10 @@ pledge_namei(struct proc *p, struct name
>>> return (0);
>>> }
>>> if (strcmp(path, "/etc/services") == 0) {
>>> + ni->ni_cnd.cn_flags |= BYPASSUNVEIL;
>>> + return (0);
>>> + }
>>> + if (strcmp(path, "/etc/protocols") == 0) {
>>> ni->ni_cnd.cn_flags |= BYPASSUNVEIL;
>>> return (0);
>
> This looks like it is fixing a real, separate bug in pledge vs
> getaddrinfo, no? (specifically: that lookups for named ports will fail
> currently).
no, our getaddrinfo currently hardcodes mapping of SOCK_STREAM, SOCK_DGRAM,
IPPROTO_TCP, and IPPROTO_UDP and maps them to "udp" and "tcp" for use when
looking up /etc/services via getservbyname_r. this is fine because they are by
far the most common case and worth optimising for.
the problem is if (when) i want to use getnameinfo to look up entries for
IPPROTO_GRE. i either hardcode IPPROTO_GRE in getnameinfo guts to "gre" for it
to pass to getservbyname_r, or i look up /etc/protocols via getprotobynumber_r
to get a name. i opted for the latter.
dlg
