The relay authentication used non-constant-time comparisons (strcasecmp,
strcmp) to verify password hashes and plaintext passwords, allowing an
attacker to derive the expected hash byte-by-byte from response timing
and then authenticate without knowing the password.
- SHA/PBKDF2 hex hash comparisons: normalize the client-supplied hash to
uppercase and compare in constant time over the fixed expected length.
- Plaintext password comparison: HMAC-SHA256 both passwords with a fresh
per-call random key and compare the fixed-size MACs in constant time,
hiding both per-byte timing and the password length.
Add string_memcmp_constant_time helper in core, exposed via the plugin
API. Bump WEECHAT_PLUGIN_API_VERSION accordingly.
At the moment, building WeeChat triggers several thousand -Wstrict-prototypes
diagnostics. This is due to its source code using an empty argument list for
functions and function pointers that take no arguments, instead of explicitly
declaring that they take no arguments by using a void list.
This commit replaces all empty argument lists with a void list.
Note that Ruby's headers also suffer the same problem, which WeeChat can't
do anything to fix. Thus, building WeeChat with the Ruby plugin enabled
will still issue approximately 30 such diagnostics.
Detail of changes:
- the save of upgrade files in plugins is now done as soon as the "upgrade"
signal is received, and not when the plugin is unloaded (it was too late to
detect any problem and prevent the upgrade to happen)
- if the write of an upgrade file fails, the signal callback in plugin now
returns WEECHAT_RC_ERROR and WeeChat checks this code to stop the upgrade as
soon as this return code is received
- a new flag is added in plugin structure: unload_with_upgrade, it is set to 1
before unloading all plugins when upgrade will happen (all *.upgrade files
are then already successfully written).
The type "enum" replaces type "integer" when used with string values.
For compatibility, any option created with type "integer" and string values is
automatically created to "enum" on creation, with no error.
Sébastien Helleu