The lhash expand() function can fail if realloc fails. The previous
implementation made changes to the structure and then attempted to do a
realloc. If the realloc failed then it attempted to undo the changes it
had just made. Unfortunately changes to lh->p were not undone correctly,
ultimately causing subsequent expand() calls to increment num_nodes to a
value higher than num_alloc_nodes, which can cause out-of-bounds reads/
writes. This is not considered a security issue because an attacker cannot
cause realloc to fail.

This commit moves the realloc call to near the beginning of the function
before any other changes are made to the lhash structure. That way if a
failure occurs we can immediately fail without having to undo anything.

Thanks to Pavel Kopyl (Samsung) for reporting this issue.
Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: NViktor Dukhovni <viktor@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4550)

indicate the level of locking required for various operations.

Remove the lock and atomics from the lhash code.  These we're not complete
or adequate.

Refer to #4418 and #4427 for details.
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NBen Kaduk <kaduk@mit.edu>
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4429)

CLA: trivial
Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: NPaul Dale <paul.dale@oracle.com>
Reviewed-by: NTim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3913)

Various initialization functions modify this table, which can cause heap
corruption in the absence of external synchronization.

Some stats are modified from OPENSSL_LH_retrieve, where callers aren't
expecting to have to take out an exclusive lock. Switch to using atomic
operations for those stats.
Reviewed-by: NMatt Caswell <matt@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3525)

Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2774)

Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1223)

Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1223)

Rename sk_xxx to OPENSSL_sk_xxx and _STACK to OPENSSL_STACK
Rename lh_xxx API to OPENSSL_LH_xxx and LHASH_NODE to OPENSSL_LH_NODE
Make lhash stuff opaque.
Use typedefs for function pointers; makes the code simpler.
Remove CHECKED_xxx macros.
Add documentation; remove old X509-oriented doc.
Add API-compat names for entire old API
Reviewed-by: NDr. Stephen Henson <steve@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>

This was done by the following
        find . -name '*.[ch]' | /tmp/pl
where /tmp/pl is the following three-line script:
        print unless $. == 1 && m@/\* .*\.[ch] \*/@;
        close ARGV if eof; # Close file to reset $.

And then some hand-editing of other files.
Reviewed-by: NViktor Dukhovni <viktor@openssl.org>

Make LHASH_OF use static inline functions.

Add new lh_get_down_load and lh_set_down_load functions and their
typesafe inline equivalents.

Make lh_error a function instead of a macro.
Reviewed-by: NRich Salz <rsalz@openssl.org>

After openssl_zalloc, cleanup more "set to 0/NULL" assignments.
Many are from github feedback.
Reviewed-by: NTim Hudson <tjh@openssl.org>

Especially since after the #ifdef cleanups this is not useful.
Reviewed-by: NMatt Caswell <matt@openssl.org>

For a local variable:
        TYPE *p;
Allocations like this are "risky":
        p = OPENSSL_malloc(sizeof(TYPE));
if the type of p changes, and the malloc call isn't updated, you
could get memory corruption.  Instead do this:
        p = OPENSSL_malloc(sizeof(*p));
Also fixed a few memset() calls that I noticed while doing this.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Following ANSI C rules, remove the casts from calls to
OPENSSL_malloc and OPENSSL_realloc.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

The following compile options (#ifdef's) are removed:
    OPENSSL_NO_BIO OPENSSL_NO_BUFFER OPENSSL_NO_CHAIN_VERIFY
    OPENSSL_NO_EVP OPENSSL_NO_FIPS_ERR OPENSSL_NO_HASH_COMP
    OPENSSL_NO_LHASH OPENSSL_NO_OBJECT OPENSSL_NO_SPEED OPENSSL_NO_STACK
    OPENSSL_NO_X509 OPENSSL_NO_X509_VERIFY

This diff is big because of updating the indents on preprocessor lines.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

indent will not alter them when reformatting comments
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>

Submitted by: Jan Pechanec <Jan.Pechanec@Sun.COM>

Check for memory allocation failures.

choice but to have to cast away "const" qualifiers from their prototypes.
This does not remove constification restrictions from hash/compare
callbacks, but allows destructor commands to be run over a tables' elements
without bad casts.

variants of stdio.h that define NULL in such a way that it's "unsafe"
to use for function pointer casting.

sure they are available in opensslconf.h, by giving them names starting
with "OPENSSL_" to avoid conflicts with other packages and by making
sure e_os2.h will cover all platform-specific cases together with
opensslconf.h.

I've checked fairly well that nothing breaks with this (apart from
external software that will adapt if they have used something like
NO_KRB5), but I can't guarantee it completely, so a review of this
change would be a good thing.

around the callbacks required in the LHASH code for the "doall" functions.

Also - fix the evil function pointer casting in the two lh_doall functions
by deferring to a static utility function. Previously lh_doall() was
invoking lh_doall_arg() by casting the callback to the 2-parameter
prototype and passing in a NULL argument. This appears to have been working
thus far but it's not a hot idea. If the extra level of indirection becomes
a performance hit, we can just provide two virtually identical
implementations for each variant later on.

functions need to be constified, and therefore meant a number of easy
changes a little everywhere.

Now, if someone could explain to me why OBJ_dup() cheats...

casts) used in the lhash code are about as horrible and evil as they can
be. For starters, the callback prototypes contain empty parameter lists.
Yuck.

This first change defines clearer prototypes - including "typedef"'d
function pointer types to use as "hash" and "compare" callbacks, as well as
the callbacks passed to the lh_doall and lh_doall_arg iteration functions.
Now at least more explicit (and clear) casting is required in all of the
dependant code - and that should be included in this commit.

The next step will be to hunt down and obliterate some of the function
pointer casting being used when it's not necessary - a particularly evil
variant exists in the implementation of lh_doall.

I didn't apply all his patches yet, since I have some hesitance about
unconstifying.  To be pondered.

like Malloc, Realloc and especially Free conflict with already existing names
on some operating systems or other packages.  That is reason enough to change
the names of the OpenSSL memory allocation macros to something that has a
better chance of being unique, like prepending them with OPENSSL_.

This change includes all the name changes needed throughout all C files.