Discovered that the DHCP server on a TrendNet router (unknown model)
provides a zero-length option 12 (Host Name) in the DHCP ACK message. This
has the effect of causing udhcpc to drop the rest of the options, including
option 51 (IP Address Lease Time), 3 (Router), and 6 (Domain Name Server),
most importantly leaving the OpenWrt device with no default gateway.
The TrendNet behavior violates RFC 2132, which in Section 3.14 declares that
option 12 has a minimum length of 1 octet. It is perhaps not a cosmic coincidence
that I found this behavior on Pi Day.
This patch allows zero length options without bailing out, by simply skipping them.
function old new delta
udhcp_scan_options 183 172 -11
Signed-off-by: Russell Senior <russell@personaltelco.net>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Added an option scanner to udhcp to enable iteration over packet options.
Signed-off-by: Martin Lewis <martin.lewis.x84@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The following caused udhcpc to segfault:
busybox udhcpc -i lo -s /dev/null -x 0x3d:
function old new delta
udhcp_str2optset 629 641 +12
Signed-off-by: Michal Kazior <michal@plume.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Back in 2007, commit 0c97c9d437 ("'simple' error message functions by
Loic Grenie") introduced bb_simple_perror_msg() to allow for a lower
overhead call to bb_perror_msg() when only a string was being printed
with no parameters. This saves space for some CPU architectures because
it avoids the overhead of a call to a variadic function. However there
has never been a simple version of bb_error_msg(), and since 2007 many
new calls to bb_perror_msg() have been added that only take a single
parameter and so could have been using bb_simple_perror_message().
This changeset introduces 'simple' versions of bb_info_msg(),
bb_error_msg(), bb_error_msg_and_die(), bb_herror_msg() and
bb_herror_msg_and_die(), and replaces all calls that only take a
single parameter, or use something like ("%s", arg), with calls to the
corresponding 'simple' version.
Since it is likely that single parameter calls to the variadic functions
may be accidentally reintroduced in the future a new debugging config
option WARN_SIMPLE_MSG has been introduced. This uses some macro magic
which will cause any such calls to generate a warning, but this is
turned off by default to avoid use of the unpleasant macros in normal
circumstances.
This is a large changeset due to the number of calls that have been
replaced. The only files that contain changes other than simple
substitution of function calls are libbb.h, libbb/herror_msg.c,
libbb/verror_msg.c and libbb/xfuncs_printf.c. In miscutils/devfsd.c,
networking/udhcp/common.h and util-linux/mdev.c additonal macros have
been added for logging so that single parameter and multiple parameter
logging variants exist.
The amount of space saved varies considerably by architecture, and was
found to be as follows (for 'defconfig' using GCC 7.4):
Arm: -92 bytes
MIPS: -52 bytes
PPC: -1836 bytes
x86_64: -938 bytes
Note that for the MIPS architecture only an exception had to be made
disabling the 'simple' calls for 'udhcp' (in networking/udhcp/common.h)
because it made these files larger on MIPS.
Signed-off-by: James Byrne <james.byrne@origamienergy.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Between Busybox 1.24.2 and 1.25.0 the bb_info_msg() function was
eliminated and calls to it changed to be bb_error_msg(). The downside of
this is that daemons now log all messages to syslog at the LOG_ERR level
which makes it hard to filter errors from informational messages.
This change optionally re-introduces bb_info_msg(), controlled by a new
option FEATURE_SYSLOG_INFO, restores all the calls to bb_info_msg() that
were removed (only in applets that set logmode to LOGMODE_SYSLOG or
LOGMODE_BOTH), and also changes informational messages in ifplugd and
ntpd.
The code size change of this is as follows (using 'defconfig' on x86_64
with gcc 7.3.0-27ubuntu1~18.04)
function old new delta
bb_info_msg - 182 +182
bb_vinfo_msg - 27 +27
static.log7 194 198 +4
log8 190 191 +1
log5 190 191 +1
crondlog 45 - -45
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 3/0 up/down: 215/-45) Total: 170 bytes
If you don't care about everything being logged at LOG_ERR level
then when FEATURE_SYSLOG_INFO is disabled Busybox actually gets smaller:
function old new delta
static.log7 194 200 +6
log8 190 193 +3
log5 190 193 +3
syslog_level 1 - -1
bb_verror_msg 583 581 -2
crondlog 45 - -45
------------------------------------------------------------------------------
(add/remove: 0/2 grow/shrink: 3/1 up/down: 12/-48) Total: -36 bytes
Signed-off-by: James Byrne <james.byrne@origamienergy.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Support for the IEEE timezone string and timezone database strings (100
and 101 options respectively) is added for ipv4, conforming to RFC-4833.
The two options are passed to hook scripts in the variables tzstr and
tzdbstr.
function old new delta
dhcp_option_strings 280 294 +14
dhcp_optflags 76 80 +4
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 18/0) Total: 18 bytes
Signed-off-by: Antoine Girard-Vallée <antoine.girard-vallee@savoirfairelinux.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
trim() modifies the string in place if needed and returns a pointer to
the end of the resulting string. Update udhcp_str2optset() so it no
longer sets the value of 'val' to the return value of trim().
Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
function old new delta
udhcp_get_option 215 220 +5
udhcp_run_script 802 803 +1
Signed-off-by: Brian Foley <bpfoley@google.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Like d3092c99, this change adds support for the DHCP "path-prefix"
option, as defined in RFC 5071. We use the string identifer
"pxepathprefix".
Adding this option makes string parsing in the hook scripts simpler.
function old new delta
dhcp_option_strings 255 269 +14
dhcp_optflags 72 74 +2
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This change adds a definition for DHCP option 209. RFC 5071 defines code
209 as a configuration file for a PXE bootloader; this change uses
the string "pxeconffile" as its text identifier.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This change retains "or later" state! No licensing _changes_ here,
only form is adjusted (article, space between "GPL" and "v2" and so on).
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>