| fbe0257b | 06-Jul-2026 |
Dag-Erling Smørgrav <des@FreeBSD.org> |
libc/resolv: Reimplement the sortlist parser
When we switched from the BIND4 resolver to the BIND9 resolver, the
sortlist parser was inadvertently disabled due to a missing #define, and
nobody seeme
libc/resolv: Reimplement the sortlist parser
When we switched from the BIND4 resolver to the BIND9 resolver, the
sortlist parser was inadvertently disabled due to a missing #define, and
nobody seemed to notice. The sorting code remained enabled in the
resolver, but there was no way to set a sort order.
Reimplement the sortlist parser, but correctly, and update the manual
accordingly. The new parser accepts IPv4 and IPv6 addresses with or
without a mask or prefix length, just like the old one, except IPv6
support was a bit wonky in the original code.
Fixes: 5342d17f09a8 ("Update the resolver in libc to BIND9's one.")
Relnotes: yes
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D57925
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|
| ffeb5690 | 06-Jul-2026 |
Dag-Erling Smørgrav <des@FreeBSD.org> |
libc/resolv: Refactor the configuration parser
This was previously all a single loop in res_init(), apart from option
parsing which we cleaned up in a previous commit. Break it out into
separate fu
libc/resolv: Refactor the configuration parser
This was previously all a single loop in res_init(), apart from option
parsing which we cleaned up in a previous commit. Break it out into
separate functions for reading the configuration line by line, setting
the default domain, setting the search list, and adding a nameserver
to the nameserver list. Sprinkle bounds checks and code comments all
around.
The sortlist code, which has been disabled for the past 20 years, will
be dealt with in a separate commit.
MFC after: 1 week
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D57924
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|
| 9bfdfecd | 06-Jul-2026 |
Dag-Erling Smørgrav <des@FreeBSD.org> |
libc/resolv: Refactor the option parser
Start the loop by finding the end of the option name, the name-value
separator (if any), and the end of the option. Use those pointers to
simplify matching t
libc/resolv: Refactor the option parser
Start the loop by finding the end of the option name, the name-value
separator (if any), and the end of the option. Use those pointers to
simplify matching the option name and parsing the option value, and
validate option names and values more strictly. This means that:
* We no longer accept trailing garbage in an option name or value. For
instance, we would previously interpret “edns0123” as “edns0” and
“timeout:3xyz” as “timeout:3”. This was actually quite lucky because
we also failed to recognize the newline at the end of the option line
as a whitespace character.
* For options that take a numerical argument, we would previously accept
negative values and treat non-numerical arguments as 0, while large
numerical arguments would be capped to the option's maximum permitted
value. Now, any failure to parse the argument, including overflow,
results in the option being left unchanged.
MFC after: 1 week
Relnotes: yes
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D57923
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|
| 702c24cc | 28-Jun-2026 |
Dag-Erling Smørgrav <des@FreeBSD.org> |
libc/resolv: Export __res_conf_name
Add a new global variable, __res_conf_name, which is initialized to
_PATH_RESCONF and used in its place by res_init(). This allows test
programs (and application
libc/resolv: Export __res_conf_name
Add a new global variable, __res_conf_name, which is initialized to
_PATH_RESCONF and used in its place by res_init(). This allows test
programs (and applications) to select a different configuration file
to read instead of /etc/resolv.conf.
PR: 220610
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|
| 507ab02d | 27-Jun-2026 |
Dag-Erling Smørgrav <des@FreeBSD.org> |
libc/resolv: Reimplement the sortlist parser
When we switched from the BIND4 resolver to the BIND9 resolver, the
sortlist parser was inadvertently disabled, and nobody noticed. The
sorting code rem
libc/resolv: Reimplement the sortlist parser
When we switched from the BIND4 resolver to the BIND9 resolver, the
sortlist parser was inadvertently disabled, and nobody noticed. The
sorting code remained enabled in the resolver, but there was no way to
set a sort order.
Reimplement the sortlist parser, but correctly, and update the
documentation accordingly. The new parser accepts IPv4 and IPv6
addresses with or without a prefix length.
Fixes: 5342d17f09a8 ("Update the resolver in libc to BIND9's one.")
Relnotes: yes
show more ...
|
| 9fd22951 | 25-Jun-2026 |
Dag-Erling Smørgrav <des@FreeBSD.org> |
libc/resolv: Refactor the configuration parser
This was previously all a single loop in res_init(), apart from option
parsing which we cleaned up in a previous commit. Break it out into
separate fu
libc/resolv: Refactor the configuration parser
This was previously all a single loop in res_init(), apart from option
parsing which we cleaned up in a previous commit. Break it out into
separate functions for reading the configuration line by line, setting
the default domain, setting the search list, and adding a nameserver
to the nameserver list. Sprinkle bounds checks and code comments all
around.
The sortlist code, which has been disabled for the past 20 years, will
be dealt with in a separate commit.
MFC after: 1 week
show more ...
|
| 40e10af6 | 25-Jun-2026 |
Dag-Erling Smørgrav <des@FreeBSD.org> |
libc/resolv: Refactor the option parser
Start the loop by finding the end of the option name, the name-value
separator (if any), and the end of the option. Use those pointers to
simplify matching t
libc/resolv: Refactor the option parser
Start the loop by finding the end of the option name, the name-value
separator (if any), and the end of the option. Use those pointers to
simplify matching the option name and parsing the option value.
This means that:
* We no longer accept trailing garbage in an option name or value. For
instance, we would previously interpret “edns0123” as “edns0” and
“timeout:3xyz” as “timeout:3”. This was actually quite lucky because
we also failed to recognize the newline at the end of the option line
as a whitespace character.
* For options that take a numerical value, we would previously happily
set a numerical option to a negative value and treat non-numerical
arguments as 0, while a numerical argument that happened to exceed
the maximum for the option would result in the option being set to its
default value. Now, any failure to parse the argument, including
overflow, results in the option being set to its default value.
MFC after: 1 week
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|