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.


NGX_MAKEFILE=$NGX_OBJS/Makefile
NGX_MODULES_C=$NGX_OBJS/ngx_modules.c

NGX_AUTO_HEADERS_H=$NGX_OBJS/ngx_auto_headers.h
NGX_AUTO_CONFIG_H=$NGX_OBJS/ngx_auto_config.h

NGX_AUTOTEST=$NGX_OBJS/autotest
NGX_AUTOCONF_ERR=$NGX_OBJS/autoconf.err

# STUBs
NGX_ERR=$NGX_OBJS/autoconf.err
MAKEFILE=$NGX_OBJS/Makefile


NGX_PCH=
NGX_USE_PCH=


# check the echo's "-n" option and "\c" capability

if echo "test\c" | grep c >/dev/null; then

    if echo -n test | grep n >/dev/null; then
        ngx_n=
        ngx_c=

    else
        ngx_n=-n
        ngx_c=
    fi

else
    ngx_n=
    ngx_c='\c'
fi


# create Makefile

cat << END > Makefile

default:	build

clean:
	rm -rf Makefile $NGX_OBJS

.PHONY:	default clean
END