SSL: use of the SSL_OP_IGNORE_UNEXPECTED_EOF option. A new behaviour was introduced in OpenSSL 1.1.1e, when a peer does not send close_notify before closing the connection. Previously, it was to return SSL_ERROR_SYSCALL with errno 0, known since at least OpenSSL 0.9.7, and is handled gracefully in nginx. Now it returns SSL_ERROR_SSL with a distinct reason SSL_R_UNEXPECTED_EOF_WHILE_READING ("unexpected eof while reading"). This leads to critical errors seen in nginx within various routines such as SSL_do_handshake(), SSL_read(), SSL_shutdown(). The behaviour was restored in OpenSSL 1.1.1f, but presents in OpenSSL 3.0 by default. Use of the SSL_OP_IGNORE_UNEXPECTED_EOF option added in OpenSSL 3.0 allows to set a compatible behaviour to return SSL_ERROR_ZERO_RETURN: https://git.openssl.org/?p=openssl.git;a=commitdiff;h=09b90e0 See for additional details: https://github.com/openssl/openssl/issues/11381

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


echo $ngx_n "checking for uintptr_t ...$ngx_c"

cat << END >> $NGX_AUTOCONF_ERR

----------------------------------------
checking for uintptr_t

END

found=no

cat << END > $NGX_AUTOTEST.c

#include <sys/types.h>
$NGX_INCLUDE_INTTYPES_H

int main(void) {
    uintptr_t i = 0;
    return (int) i;
}

END

ngx_test="$CC $CC_TEST_FLAGS $CC_AUX_FLAGS \
          -o $NGX_AUTOTEST $NGX_AUTOTEST.c $NGX_LD_OPT"

eval "$ngx_test >> $NGX_AUTOCONF_ERR 2>&1"

if [ -x $NGX_AUTOTEST ]; then
    echo " uintptr_t found"
    found=yes
else
    echo $ngx_n " uintptr_t not found" $ngx_c
fi

rm -rf $NGX_AUTOTEST*


if [ $found = no ]; then
    found="uint`expr 8 \* $ngx_ptr_size`_t"
    echo ", $found used"

    echo "typedef $found  uintptr_t;"                   >> $NGX_AUTO_CONFIG_H
    echo "typedef $found  intptr_t;" | sed -e 's/u//g'  >> $NGX_AUTO_CONFIG_H
fi