Since 0.2.3.1-alpha, we've supported the Linux extensions to socket(),
open(), socketpair(), and accept() that enable us to create an fd and
make it close-on-exec with a single syscall. This not only saves us a
syscall (big deal), but makes us less vulnerable to race conditions
where we open a socket and then exec before we can make it
close-on-exec.
But these extensions are not supported on all Linuxes: They were added
between 2.6.23 or so and 2.6.28 or so. If you were to build your Tor
against a recent Linux's kernel headers, and then run it with a older
kernel, you would find yourselve unable to open sockets. Ouch!
The solution here is that, when one of these syscalls fails with
EINVAL, we should try again in the portable way. This adds an extra
syscall in the case where we built with new headers and are running
with old ones, but it will at least allow Tor to work.
Fixes bug 5112; bugfix on 0.2.3.1-alpha.
There is a facility (not used now in Tor) to avoid storing the hash
of a given type if it is a fast-to-calculate hash.
There are also a few ancient-openbsd compilation issues fixed here.
The fact that Tor says INLINE while Libevent says inline remains
unaddressed.
in Makefile.am, we used it without quoting it, causing build failure if
your openssl/sed/sha1sum happened to live in a directory with a space in
it (very common on windows)
There was one MS_WINDOWS that remained because it wasn't on a macro
line; a few remaining uses (and the definition!) in configure.in;
and a now-nonsensical stanza of eventdns_tor.h that previously
defined 'WIN32' if it didn't exist.
This commit is completely mechanical; I used this perl script to make it:
#!/usr/bin/perl -w -i.bak -p
if (/^\s*\#/) {
s/MS_WINDOWS/_WIN32/g;
s/\bWIN32\b/_WIN32/g;
}
These were found by looking for tor_snprintf() instances that were
preceeded closely by tor_malloc(), though I probably converted some
more snprintfs as well.
(In every case, make sure that the length variable (if any) is
removed, renamed, or lowered, so that anything else that might have
assumed a longer buffer doesn't exist.)
To solve bug 4779, we want to avoid OpenSSL 1.0.0's counter mode.
But Fedora (and maybe others) lie about the actual OpenSSL version,
so we can't trust the header to tell us if it's safe.
Instead, let's do a run-time test to see whether it's safe, and if
not, use our built-in version.
fermenthor contributed a pretty essential fixup to this patch. Thanks!
MAX_DNS_LABEL_SIZE was only defined for old versions of openssl, which
broke the build. Spotted by xiando. Fixes bug 4413; not in any released
version.
The thing that's limited to 63 bytes is a "label", not a hostname.
Docment input constraints and behavior on bogus inputs.
Generally it's better to check for overflow-like conditions before
than after. In this case, it's not a true overflow, so we're okay,
but let's be consistent.
pedantic less->fewer in the documentation
Fixes bug 4413; bugfix on xxxx.
Hostname components cannot be larger than 63 characters.
This simple check makes certain randlen cannot overflow rand_bytes_len.