Compiler cannot find the declaration for pm_sm_authenticate and prints
the following warning (split due to long line):
pam_test.c:184:10: warning: implicit declaration of function
‘pam_sm_authenticate’; did you mean ‘pam_authenticate’?
[-Wimplicit-function-declaration]
This makes sure that file descriptors will be closed, even if the
fdopen() call failes, which was overlooked in some cases beforehand.
Should be not an issue in the real world, but let's be as clean as
possible.
strncpy() is _NOT_ a safe version of strcpy() and it should not be used
(ineffective and dangerous since a NUL termination might be missing).
Instead snprintf() the way to safely construct a string with a given
limit. This commit implements this for the action parsing in ykpamcfg.
This checks the return code of snprintf() and makes sure that fullpath
actually fits into a buffer of size PATH_MAX. Otherwise, it will output
an error and exit.
Instead of hardcoding the buffer size to 256, using PATH_MAX makes more
sense here, since this can be defined differently on different
platforms. This is not perfect, though, refer to [1] for some details.
In our case it should be good enough.
[1]: https://eklitzke.org/path-max-is-tricky
Certain phrases (Challenge-response) were not spelled consistently
throughout the project. This commit adjusts for that and fixes a
couple of typos along the way and uses the base form of verbs in
case of error messages.
A previous commit (d51124e) added the `e` flag to the `fopen()` calls. However
this flag is not supported on all platforms (MacOS) and will be silently
dropped (see #145). This patch works around those issues by manually opening
the file descriptor using `open()` with the `O_CLOEXEC` flag, and invoking
`fd_open()` on the resulting file descriptor to open an appropriate `FILE`
stream.
This makes sure that all files used by pam_yubico will be opened with the
`O_CLOEXEC` flag on all supported platforms to mitigate issues with missing
`fclose()` invocation (see #136).
