检查版本，安装pecl支持
php -v # 检查版本，确定为php7.2
pecl version
sudo apt-get install php-pear
sudo apt-get install php7.2-dev
安装 mcrypt extension
mcrypt支持查看 http://pecl.php.net/package-info.php?package=mcrypt&version=1.0.1
sudo apt-get -y install gcc make autoconf libc-dev pkg-config
sudo apt-get -y install libmcrypt-dev
sudo pecl install mcrypt-1.0.1
输出以下信息，直接回车就行
WARNING: channel "pecl.php.net" has updated its protocols, use "pecl channel-update pecl.php.net" to update
downloading mcrypt-1.0.1.tgz ...
Starting to download mcrypt-1.0.1.tgz (33,782 bytes)
.........done: 33,782 bytes
6 source files, building
running: phpize
Configuring for:
PHP Api Version: 20170718
Zend Module Api No: 20170718
Zend Extension Api No: 320170718
libmcrypt prefix? [autodetect] :
building in /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1
running: /tmp/pear/temp/mcrypt/configure --with-php-config=/usr/bin/php-config --with-mcrypt
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for a sed that does not truncate output... /bin/sed
checking for cc... cc
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables...
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether cc accepts -g... yes
checking for cc option to accept ISO C89... none needed
checking how to run the C preprocessor... cc -E
checking for icc... no
checking for suncc... no
checking whether cc understands -c and -o together... yes
checking for system library directory... lib
checking if compiler supports -R... no
checking if compiler supports -Wl,-rpath,... yes
checking build system type... x86_64-pc-linux-gnu
checking host system type... x86_64-pc-linux-gnu
checking target system type... x86_64-pc-linux-gnu
checking for PHP prefix... /usr
checking for PHP includes... -I/usr/include/php/20170718 -I/usr/include/php/20170718/main -I/usr/include/php/20170718/TSRM -I/usr/include/php/20170718/Zend -I/usr/include/php/20170718/ext -I/usr/include/php/20170718/ext/date/lib
checking for PHP extension directory... /usr/lib/php/20170718
checking for PHP installed headers prefix... /usr/include/php/20170718
checking if debug is enabled... no
checking if zts is enabled... no
checking for re2c... no
configure: WARNING: You will need re2c 0.13.4 or later if you want to regenerate PHP parsers.
checking for gawk... gawk
checking for mcrypt support... yes, shared
checking for libmcrypt version... >= 2.5.6
checking for mcrypt_module_open in -lmcrypt... yes
checking how to print strings... printf
checking for a sed that does not truncate output... (cached) /bin/sed
checking for fgrep... /bin/grep -F
checking for ld used by cc... /usr/bin/x86_64-linux-gnu-ld
checking if the linker (/usr/bin/x86_64-linux-gnu-ld) is GNU ld... yes
checking for BSD- or MS-compatible name lister (nm)... /usr/bin/nm -B
checking the name lister (/usr/bin/nm -B) interface... BSD nm
checking whether ln -s works... yes
checking the maximum length of command line arguments... 1572864
checking how to convert x86_64-pc-linux-gnu file names to x86_64-pc-linux-gnu format... func_convert_file_noop
checking how to convert x86_64-pc-linux-gnu file names to toolchain format... func_convert_file_noop
checking for /usr/bin/x86_64-linux-gnu-ld option to reload object files... -r
checking for objdump... objdump
checking how to recognize dependent libraries... pass_all
checking for dlltool... no
checking how to associate runtime and link libraries... printf %s\n
checking for ar... ar
checking for archiver @FILE support... @
checking for strip... strip
checking for ranlib... ranlib
checking for gawk... (cached) gawk
checking command to parse /usr/bin/nm -B output from cc object... ok
checking for sysroot... no
checking for a working dd... /bin/dd
checking how to truncate binary pipes... /bin/dd bs=4096 count=1
checking for mt... mt
checking if mt is a manifest tool... no
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking for dlfcn.h... yes
checking for objdir... .libs
checking if cc supports -fno-rtti -fno-exceptions... no
checking for cc option to produce PIC... -fPIC -DPIC
checking if cc PIC flag -fPIC -DPIC works... yes
checking if cc static flag -static works... yes
checking if cc supports -c -o file.o... yes
checking if cc supports -c -o file.o... (cached) yes
checking whether the cc linker (/usr/bin/x86_64-linux-gnu-ld -m elf_x86_64) supports shared libraries... yes
checking whether -lc should be explicitly linked in... no
checking dynamic linker characteristics... GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking whether stripping libraries is possible... yes
checking if libtool supports shared libraries... yes
checking whether to build shared libraries... yes
checking whether to build static libraries... no
configure: creating ./config.status
config.status: creating config.h
config.status: executing libtool commands
running: make
/bin/bash /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/libtool --mode=compile cc -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1 -I. -I/tmp/pear/temp/mcrypt -DPHP_ATOM_INC -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/include -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/main -I/tmp/pear/temp/mcrypt -I/usr/include/php/20170718 -I/usr/include/php/20170718/main -I/usr/include/php/20170718/TSRM -I/usr/include/php/20170718/Zend -I/usr/include/php/20170718/ext -I/usr/include/php/20170718/ext/date/lib -DHAVE_CONFIG_H -g -O2 -c /tmp/pear/temp/mcrypt/mcrypt.c -o mcrypt.lo
libtool: compile: cc -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1 -I. -I/tmp/pear/temp/mcrypt -DPHP_ATOM_INC -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/include -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/main -I/tmp/pear/temp/mcrypt -I/usr/include/php/20170718 -I/usr/include/php/20170718/main -I/usr/include/php/20170718/TSRM -I/usr/include/php/20170718/Zend -I/usr/include/php/20170718/ext -I/usr/include/php/20170718/ext/date/lib -DHAVE_CONFIG_H -g -O2 -c /tmp/pear/temp/mcrypt/mcrypt.c -fPIC -DPIC -o .libs/mcrypt.o
/bin/bash /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/libtool --mode=compile cc -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1 -I. -I/tmp/pear/temp/mcrypt -DPHP_ATOM_INC -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/include -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/main -I/tmp/pear/temp/mcrypt -I/usr/include/php/20170718 -I/usr/include/php/20170718/main -I/usr/include/php/20170718/TSRM -I/usr/include/php/20170718/Zend -I/usr/include/php/20170718/ext -I/usr/include/php/20170718/ext/date/lib -DHAVE_CONFIG_H -g -O2 -c /tmp/pear/temp/mcrypt/mcrypt_filter.c -o mcrypt_filter.lo
libtool: compile: cc -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1 -I. -I/tmp/pear/temp/mcrypt -DPHP_ATOM_INC -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/include -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/main -I/tmp/pear/temp/mcrypt -I/usr/include/php/20170718 -I/usr/include/php/20170718/main -I/usr/include/php/20170718/TSRM -I/usr/include/php/20170718/Zend -I/usr/include/php/20170718/ext -I/usr/include/php/20170718/ext/date/lib -DHAVE_CONFIG_H -g -O2 -c /tmp/pear/temp/mcrypt/mcrypt_filter.c -fPIC -DPIC -o .libs/mcrypt_filter.o
/bin/bash /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/libtool --mode=link cc -DPHP_ATOM_INC -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/include -I/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/main -I/tmp/pear/temp/mcrypt -I/usr/include/php/20170718 -I/usr/include/php/20170718/main -I/usr/include/php/20170718/TSRM -I/usr/include/php/20170718/Zend -I/usr/include/php/20170718/ext -I/usr/include/php/20170718/ext/date/lib -DHAVE_CONFIG_H -g -O2 -o mcrypt.la -export-dynamic -avoid-version -prefer-pic -module -rpath /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/modules mcrypt.lo mcrypt_filter.lo -lmcrypt -lltdl
libtool: link: cc -shared -fPIC -DPIC .libs/mcrypt.o .libs/mcrypt_filter.o /usr/lib/libmcrypt.so /usr/lib/x86_64-linux-gnu/libltdl.so -g -O2 -Wl,-soname -Wl,mcrypt.so -o .libs/mcrypt.so
libtool: link: ( cd ".libs" && rm -f "mcrypt.la" && ln -s "../mcrypt.la" "mcrypt.la" )
/bin/bash /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/libtool --mode=install cp ./mcrypt.la /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/modules
libtool: install: cp ./.libs/mcrypt.so /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/modules/mcrypt.so
libtool: install: cp ./.libs/mcrypt.lai /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/modules/mcrypt.la
libtool: finish: PATH="/usr/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin:/sbin" ldconfig -n /tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/modules
----------------------------------------------------------------------
Libraries have been installed in:
/tmp/pear/temp/pear-build-rooteTY7Qo/mcrypt-1.0.1/modules
If you ever happen to want to link against installed libraries
in a given directory, LIBDIR, you must either use libtool, and
specify the full pathname of the library, or use the '-LLIBDIR'
flag during linking and do at least one of the following:
- add LIBDIR to the 'LD_LIBRARY_PATH' environment variable
during execution
- add LIBDIR to the 'LD_RUN_PATH' environment variable
during linking
- use the '-Wl,-rpath -Wl,LIBDIR' linker flag
- have your system administrator add LIBDIR to '/etc/ld.so.conf'
See any operating system documentation about shared libraries for
more information, such as the ld(1) and ld.so(8) manual pages.
----------------------------------------------------------------------
Build complete.
Don't forget to run 'make test'.
running: make INSTALL_ROOT="/tmp/pear/temp/pear-build-rooteTY7Qo/install-mcrypt-1.0.1" install
Installing shared extensions: /tmp/pear/temp/pear-build-rooteTY7Qo/install-mcrypt-1.0.1/usr/lib/php/20170718/
running: find "/tmp/pear/temp/pear-build-rooteTY7Qo/install-mcrypt-1.0.1" | xargs ls -dils
786579 4 drwxr-xr-x 3 root root 4096 Jul 6 09:35 /tmp/pear/temp/pear-build-rooteTY7Qo/install-mcrypt-1.0.1
786603 4 drwxr-xr-x 3 root root 4096 Jul 6 09:35 /tmp/pear/temp/pear-build-rooteTY7Qo/install-mcrypt-1.0.1/usr
786604 4 drwxr-xr-x 3 root root 4096 Jul 6 09:35 /tmp/pear/temp/pear-build-rooteTY7Qo/install-mcrypt-1.0.1/usr/lib
786605 4 drwxr-xr-x 3 root root 4096 Jul 6 09:35 /tmp/pear/temp/pear-build-rooteTY7Qo/install-mcrypt-1.0.1/usr/lib/php
786606 4 drwxr-xr-x 2 root root 4096 Jul 6 09:35 /tmp/pear/temp/pear-build-rooteTY7Qo/install-mcrypt-1.0.1/usr/lib/php/20170718
786601 188 -rwxr-xr-x 1 root root 189056 Jul 6 09:35 /tmp/pear/temp/pear-build-rooteTY7Qo/install-mcrypt-1.0.1/usr/lib/php/20170718/mcrypt.so
Build process completed successfully
Installing '/usr/lib/php/20170718/mcrypt.so'
install ok: channel://pecl.php.net/mcrypt-1.0.1
configuration option "php_ini" is not set to php.ini location
You should add "extension=mcrypt.so" to php.ini
添加扩展信息
sudo nano /etc/php/7.2/mods-available/20-mcrypt.ini
添加内容：extension=mcrypt.so
然后连接到conf.d
sudo ln -s /etc/php/7.2/mods-available/20-mcrypt.ini /etc/php/7.2/cli/conf.d/
检查扩展
php -i | grep mcrypt
输出以下信息代表OK
/etc/php/7.2/cli/conf.d/20-mcrypt.ini,
Registered Stream Filters => zlib.*, string.rot13, string.toupper, string.tolower, string.strip_tags, convert.*, consumed, dechunk, convert.iconv.*, mcrypt.*, mdecrypt.*
mcrypt
mcrypt support => enabled
mcrypt_filter support => enabled
mcrypt.algorithms_dir => no value => no value
mcrypt.modes_dir => no value => no value