Commit Graph

4 Commits

Author SHA1 Message Date
christos b19025f3ec PR/56448: Solomon Ritzow: Various improvements.
Rate limiting code has been moved to ratelimit.c. I renamed
clear_ip_list to rl_clear_ip_list and broke the code up into more
functions. I have also made the per-IP rate limiting allocation more
efficient. IP addresses are now stored in their network format instead
of a string from getnameinfo (see inetd.h struct rl_ip_node). malloc
calls use only the space needed by the structure by using offsetof on
union members (I suppose this can be a bit dangerous if not done
correctly...). Per-IP rate limiting still supports textual comparison
using getnameinfo for address families other than AF_INET and AF_INET6, but I
don't think there are any that are actually compatible or used by inetd (I
haven't tested UNIX sockets with a remote bound to another file, but I did test
using IPv6 with the textual format by commenting out the IPv6 specific
code, and it works properly). Still potentially handy for the future.
The IP node list (se_rl_ip_list) now uses the <sys/queue.h> SLIST macros
instead of a custom list. I've broken rl_process up into helper functions
for each type of rate limiting and created a separate function for
address stringification, for use with printouts from the -d flag. I
tried to reduce stack memory use by moving printing code involving
string buffers into separate functions. I haven't tested rl_ipv6_eq on
a 32-bit system.

The code for the positional syntax has also been moved to parse.c.
Function try_biltin has been added to remove parse.c:parse_server's
dependency on the biltin structure definition.

File inetd.h has been updated with the proper function prototypes, and
the servtab structure has been update with the new IP node SLIST. I also
moved things around a bit. The way we (a peer and myself)
formatted inetd.h previously was somewhat confusing. Function and global
variable prototypes are now organized by the source file they are
defined in.

I also added a -f flag that I saw in another problem report
(https://gnats.netbsd.org/12823) that I thought could be useful. It
runs inetd in the foreground but without debug printouts or SO_DEBUG.
I'm not completely sure about the line "if (foreground) setsid()" that
I changed from "if (debug) setsid()".
2021-10-12 19:08:04 +00:00
rillig adeed07f1b inetd: prepare for lint's strict bool mode
Lint's strict bool mode considers bool incompatible with the other
scalar types.  This makes the type of expressions more visible in the
code.  In particular, conditions of the form '!strcmp(...)' are no
longer allowed, they have to be written as 'strcmp(...) == 0'.

The operator '!' cannot be used with sep->se_wait since that has type
pid_t, not bool.

No change to the resulting binary.
2021-09-03 20:24:28 +00:00
rillig 9805323331 inetd: remove trailing whitespace 2021-08-30 17:32:23 +00:00
christos 2557380693 Inetd enhancements by James Browning, Gabe Coffland, Alex Gavin, Solomon Ritzow
Described in:
    https://www.mail-archive.com/tech-userlevel@netbsd.org/msg03114.html
And developed in:
    https://github.com/ritzow/src/pull/1

From their notes:

All new functionality should be explained by the updated manpage.

The manpage has been refactored a bit: A new section "Directives"
has been added and the information about default hostnames and
IPsec directives has been moved there, and the new file include
directive information is also there.

getconfigent has the most major changes. A newline is no longer
read immediately, but is called only by a "goto more" (inside an
if(false) block). This allows multiple definitions or directives
to exist on a single line for anything that doesn't terminate using
a newline. This means a key-values service definition can be followed
by another key-values service definition, a positional definition,
or an ipsec, hostname, or .include directive on the same line.

memset is no longer used explicitly to clear the servtab structure,
a function init_servtab() is used instead, which uses a C struct
initializer.

The servtab se_group field is its own allocation now, and not just
a pointer into the user:group string.

Refactored some stuff out of getconfigent to separate functions
for use by parse_v2.c. These functions in inetd.c are named with
the form parse_*()

parse_v2.c only has code for parsing a key-values service definition
into a provided servtab. It should not have anything that affects
global state other than line and line_number.

Some function prototypes, structures, and #defines have been moved
from inetd.c to inetd.h.

The function config_root replaces config as the function called on
a config file load/reload. The code removed from the end of
config(void) is now called in config_root, so it is not run on each
recursive config call.

setconfig(void) was removed and its code added into config_root
because that is the only place it is called, and redundant checks
for non-null globals were removed because they are always freed by
endconfig. The fseek code was also removed because the config files
are always closed by endconfig.

Rate limiting code was updated to add a per-service per-IP rate
limiting form. Some of that code was refactored out of other places
into functions with names in the form rl_*()

We have not added any of the license or version information to the
new files parse_v2.c, parse_v2.h, and inetd.h and we have not
updated the license or version info for inetd.c.

Security related:

The behavior when reading invalid IPsec strings has changed. Inetd
no longer exits, it quits reading the current config file instead.
Could this impact program security?

We have not checked for memory leaks. Solomon tried to use dmalloc
without success. getconfigent seemed to have a memory leak at each
"goto more". It seems like inetd has never free'd allocated strings
when throwing away erroneous service definitions during parsing
(i.e. when "goto more" is called when parsing fields). OpenBSD's
version calls freeconfig on "goto more"
(c5eae130d6/usr.sbin/inetd/inetd.c (L1049))
but NetBSD only calls it when service definitions are no longer
needed. This has been fixed. freeconfig is called immediately before
any "goto more". There shouldn't be any time when a servtab is in
an invalid state where freeconfig would break.
2021-08-29 09:54:18 +00:00