Use salt_len_in instead of strlen(salt) or PHP_MAX_SALT_LEN, otherwise too
much memory will be allocated.
sha512 has a 86 character checksum, not 43. That probably was a copy&paste
from the sha256 code which indeed has 43.
The allocation also was using sizeof(char *), thus allocating 4 or 8 times
as much memory as necessary. The sizeof(char *) was removed in the 5.4
branch in b7a92c9 but forgotten on 5.3.
The memset 0 call was using PHP_MAX_SALT_LEN which can be smaller than the
output buffer and thus not zeroing out everything. Use the size of the
output buffer (needed) instead.
json_encode() no longer throws warnings. Instead only the error code for
json_last_error() is set.
As it is hard to debug the error from just an error code an optional
$as_string parameter was added to json_last_error(), which returns an
error message instead of an error code.
base64_encode used safe_emalloc, but one of the arguments was derived from a
multiplication, thus making the allocation unsafe again.
There was a size check in place, but it was off by a factor of two as it
didn't account for the signedness of the integer type.
The unsafe allocation is not exploitable, but still causes funny behavior
when the sized overflows into a negative number.
To fix the issue the *4 factor is moved into the size argument (where it is
known to be safe), so safe_emalloc can carry out the multiplication.
The size check is removed as it doesn't really make sense once safe_emalloc
works correctly. (Would only cause base64_encode to silently return false
instead of throwing an error. Also could cause problems with other uses of
the base64 encoding API, which all don't check for a NULL return value.)
Furthermore the (length + 2) < 0 check is replaced with just length < 0.
Allowing lengths -2 and -1 doesn't make sense semantically and also is not
honored in the following code (negative length would access unallocated
memory.)
Actually the length < 0 check doesn't make sense altogether, but I left it
there just to be safe.
json_encode() now returns bool(false) for all possible errors, throws the
respective warning and also sets the respective json_last_error() error
code. Three new error codes have been added:
* JSON_ERROR_RECURSION
* JSON_ERROR_INF_OR_NAN
* JSON_ERROR_UNSUPPORTED_TYPE
To get a partial JSON output instead of bool(false) the option
JSON_PARTIAL_OUTPUT_ON_ERROR can be specified. In this case the invalid
segments will be replaced either by null (for recursion, unsupported type
and invalid JSON) or 0 (for Inf and NaN).
The warning for invalid UTF-8 stays intact and is thrown also with
display_errors = On. If this behavior is undesired this can be remedied
later.
