PF_RING介绍：
PF_RING下载（2018年1月）
https://www.ntop.org/get-started/download/#PF_RING
编译：
cd PF_RING
make
交叉编译：
背景：项目中需要在一个openwrt环境下植入PF_RING动态库。首先是生产此库。
平台：编译平台为ubuntu12.04, 交叉编译平台为高通ipq4019, arm7;
步骤：
1.建立package/utils/pfring，文件结构如下；
2.将网上下载RF_RING下的文件拷贝到src目录下，文件结构如下；
├── pfring
│ ├── Makefile
│ └── src
│ ├── ChangeLog
│ ├── doc
│ ├── drivers
│ ├── kernel
│ ├── LICENSE
│ ├── Makefile
│ ├── package
│ ├── README
│ ├── README.FIRST
│ ├── README.md
│ ├── tools
│ └── userland
3. pfring/Makefile如下：
include $(TOPDIR)/rules.mk PKG_NAME:=pfring PKG_RELEASE:=1 PKG_BUILD_DIR:=$(BUILD_DIR)/$(PKG_NAME) include $(INCLUDE_DIR)/package.mk define Package/pfring SECTION:=utils CATEGORY:=Utilities TITLE:=pf_ring -- output libpfring.so endef define Package/pfring/description It's my first package demo. endef define Build/Prepare echo "Here is Package/Prepare" mkdir -p $(PKG_BUILD_DIR) $(CP) ./src/* $(PKG_BUILD_DIR)/ endef define Package/pfring/install echo "Here is Package/install" # $(INSTALL_DIR) $(1)/bin # $(INSTALL_BIN) $(PKG_BUILD_DIR)/pfring $(1)/bin/ $(INSTALL_DIR) $(1)/usr/lib $(CP) $(PKG_BUILD_DIR)/userland/deplib/* $(1)/usr/lib $(CP) $(PKG_BUILD_DIR)/userland/lib/*.so $(1)/usr/lib endef $(eval $(call BuildPackage,pfring)) ~ ~
4. 修改src下makefile，使用交叉工具链
主Makefile如下，
all: cd kernel; make cd userland; make cd drivers; make clean: cd kernel; make clean cd userland; make clean cd drivers; make clean -cd userland/snort/pfring-daq-module; make clean snort: cd userland/snort/pfring-daq-module; autoreconf -ivf; ./configure; make cd userland/snort/pfring-daq-module-zc; autoreconf -ivf; ./configure; make changelog: git log --since={`curl -s https://sourceforge.net/projects/ntop/files/PF_RING/|grep -o "<td headers="files_date_h" class="opt"><abbr title="[^"]*">[^<]*</abbr></td>"|head -n 3|tail -n 1|egrep -o "[0-9]+-[0-9]+-[0-9]+"|head -n 1`} --name-only --pretty=format:" - %s" > ./doc/Changelog.txt documentation: cd doc; make cd doc/doxygen; doxygen Doxyfile
此处主要使用make all和make clean；使用交叉编译工具链，需要在make 后加入参数如下：
make CROSS_COMPILE=arm-openwrt-linux-uclibcgnueabi- ARCH=arm
整过过程是逢山开路，遇水搭桥，不过过程艰辛。有问题的可以私聊。主要遇到的问题归结如下
错误1
CC [M] /home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/kernel/pf_ring.o
cc1: note: someone does not honour COPTS correctly, passed 0 times
In file included from include/asm-generic/int-ll64.h:10:0,
from ./arch/arm/include/asm/types.h:4,
from include/uapi/linux/types.h:4,
from include/linux/types.h:5,
from include/linux/list.h:4,
from include/linux/module.h:9,
from /home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/kernel/pf_ring.c:78:
include/uapi/asm-generic/int-ll64.h:11:29: fatal error: asm/bitsperlong.h: No such file or directory
compilation terminated.
make[6]: *** [/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/kernel/pf_ring.o] Error 1
make[5]: *** [_module_/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/kernel] Error 2
make[5]: Leaving directory `/usr/src/linux-headers-4.4.0-31-generic'
make[4]: *** [all] Error 2
make[4]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/kernel'
make[3]: *** [all] Error 2
make[3]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring'
make[2]: *** [/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/.built] Error 2
make[2]: Leaving directory `/home/box/work/xitong/qca/qca.git/qsdk/package/utils/pfring'
make[1]: *** [package/utils/pfring/compile] Error 2
make[1]: Leaving directory `/home/box/work/xitong/qca/qca.git/qsdk'
make: *** [package/utils/pfring/compile] Error 2
1） 在vi kernel/pf_ring.c下增加kernel/pf_ring.c
2）在qca/src/linux-3.14/include/ uapi/asm-generic/int-ll64.h修改
//#include <asm/bitsperlong.h>
#include <asm-generic/bitsperlong.h>
思路：此处一直认为是内核库里没有bitsperlong.h文件，随着查资料才知道是因为没有使用交叉编译工具导致。如果使用平台的编译工具，编译时用的是gcc， 如果使用交叉编译环境，编译工具为arm-openwrt-linux-uclibcgnueabi-gcc;
在PF_RING中需要修改交叉编译变量，方法如下,在make中加入参数CROSS_COMPILE=arm-openwrt-linux-uclibcgnueabi- ARCH=arm
Make à
Make CROSS_COMPILE=arm-openwrt-linux-uclibcgnueabi- ARCH=arm
错误2
include/uapi/linux/types.h:4:23: fatal error: asm/types.h: No such file or directory
#include <asm/types.h>
^
compilation terminated.
make[6]: *** [/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/kernel/pf_ring.o] Error 1
make[5]: *** [_module_/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/kernel] Error 2
make[5]: Leaving directory `/usr/src/linux-headers-3.11.0-15-generic'
make[4]: *** [all] Error 2
make[4]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/kernel'
make[3]: *** [all] Error 2
make[3]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring'
make[2]: *** [/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/.built] Error 2
make[2]: Leaving directory `/home/pon/qca/qca.git/qsdk/package/utils/pfring'
make[1]: *** [package/utils/pfring/compile] Error 2
make[1]: Leaving directory `/home/pon/qca/qca.git/qsdk'
有以下解释
http://blog.csdn.net/luckywang1103/article/details/38112281
在linux中包含头文件时，有不少类似如下的写法：#include<asm/types.h>，但在linux kernel的include文件夹下并没有这个文件夹，倒是有不少以asm打头的文件夹，如：asm_powerpc、asm_ppc等。
源代码中没有asm这个文件夹，asm是一个符号连接，只有在你的主makefile的ARCH 变量赋值，编译内核的时候根据ARCH 的配置，
临时的生成asm文件夹及其下的文件，然后指向对应的体系结构的文件，如/include/asm-arm/ ，/include/asm-x86/
这样#include <asm/types.h> ＝＝/include/asm-x86/types.h
错误1，2的解决方法：
上面两个问题是编译kernel没有编译通过：
修改makefile中的make如下：
/home/pon/qca/qca.git/qsdk/package/utils/pfring/src/kernel/Makefile:
修改前：
$(MAKE) -C $(KERNEL_DIR) SUBDIRS=$(PWD) modules
修改后：
make CROSS_COMPILE=arm-openwrt-linux-uclibcgnueabi- ARCH=arm -C /home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/linux-ipq806x/linux-3.14.77/ M=/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/kernel EXTRA_CFLAGS='${EXTRA_CFLAGS}' modules
注意：此处存在隐患，如果工程更改了位置，此处需要路径需要修改；
错误3
checking for gcc... arm-openwrt-linux-uclibcgnueabi-gcc
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... configure: error: in `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/userland':
configure: error: cannot run C compiled programs.
If you meant to cross compile, use `--host'.
See `config.log' for more details
make[4]: *** [lib/Makefile] Error 1
make[4]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/userland'
make[3]: *** [all] Error 2
make[3]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring'
make[2]: *** [/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/.built] Error 2
make[2]: Leaving directory `/home/pon/qca/qca.git/qsdk/package/utils/pfring'
make[1]: *** [package/utils/pfring/compile] Error 2
make[1]: Leaving directory `/home/pon/qca/qca.git/qsdk'
make: *** [package/utils/pfring/compile] 错误 2
原因：
没有编译平台信息；
解决：
在编译平台上运行uname -m，查看平台信息，将其放在--host=后面
修改文件package/utils/pfring/src/userland/Makefile，增加--host=arm
lib/Makefile:
./configure --host=arm
错误4
ar rs libpfring.a pfring.o pfring_mod.o pfring_utils.o pfring_mod_stack.o pfring_hw_filtering.o pfring_hw_timestamp.o pfring_mod_sysdig.o `ar t ../nbpf/libnbpf.a | grep -F .o | tr ' ' ' '`
ranlib libpfring.a
=*= making library libpfring.so =*=
gcc -Wl,-soname,libpfring.so.1 -g -shared pfring.o pfring_mod.o pfring_utils.o pfring_mod_stack.o pfring_hw_filtering.o pfring_hw_timestamp.o pfring_mod_sysdig.o `ar t ../nbpf/libnbpf.a | grep -F .o | tr ' ' ' '` -lpthread -lrt -ldl -lnl-genl-3 -lnl-3 -o libpfring.so
/usr/bin/ld: error: cannot find -lnl-genl-3
/usr/bin/ld: error: cannot find -lnl-3
collect2: ld returned 1 exit status
make[5]: *** [libpfring.so] Error 1
make[5]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/userland/lib'
make[4]: *** [libpfring] Error 2
make[4]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/userland'
make[3]: *** [all] Error 2
make[3]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring'
make[2]: *** [/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/.built] Error 2
make[2]: Leaving directory `/home/pon/qca/qca.git/qsdk/package/utils/pfring'
make[1]: *** [package/utils/pfring/compile] Error 2
make[1]: Leaving directory `/home/pon/qca/qca.git/qsdk'
make: *** [package/utils/pfring/compile] 错误 2
思路：
提示缺少两个库libnl-genl-3.so，libnl-3.so
pon@ubuntu:~/qca/qca.git/qsdk/build_dir$ find -name libnl-genl-3.so
./target-arm_cortex-a7_uClibc-1.0.14_eabi/libnl-3.2.21/ipkg-install/usr/lib/libnl-genl-3.so
./target-arm_cortex-a7_uClibc-1.0.14_eabi/libnl-3.2.21/lib/.libs/libnl-genl-3.so
pon@ubuntu:~/qca/qca.git/qsdk/build_dir$
pon@ubuntu:~/qca/qca.git/qsdk/build_dir$ find -name libnl-3.so
./target-arm_cortex-a7_uClibc-1.0.14_eabi/libnl-3.2.21/ipkg-install/usr/lib/libnl-3.so
./target-arm_cortex-a7_uClibc-1.0.14_eabi/libnl-3.2.21/lib/.libs/libnl-3.so
pon@ubuntu:~/qca/qca.git/qsdk/build_dir$
搜索文档发现是有有这两个库，只是编译过程中没有找到这两个库；
在package/utils/pfring/src/userland/configure：3605行通过-L加入.so绝对路径，编程错误提示
unsupported ELF machine number 40
考虑此处应该引用编译平台的库文件。在系统/usr/lib下没有找到libnl-genl-3.so和libnl-3.so，通过下面命令按照这两个库
sudo apt-get install libnl-3-dev
sudo apt-get install libnl-genl-3-dev
然后编译通过，编译后运行
file pfring/userland/lib/libpfring.so
pfring/userland/lib/libpfring.so: ELF 32-bit LSB shared object, Intel 80386, version 1 (SYSV), dynamically linked, BuildID[sha1]=0x889bffb8f6b7d868873ea99fa9cfd5a0cd91a8e0, not stripped
说明没有通过交叉编译生产lib库；
在package/utils/pfring/src/userland/Makefile中make增加参数
make CROSS_COMPILE=arm-openwrt-linux-uclibcgnueabi- ARCH=arm
错误5
编译后
cc1: note: someone does not honour COPTS correctly, passed 0 times
=*= making library libpfring.a =*=
ar rs libpfring.a pfring.o pfring_mod.o pfring_utils.o pfring_mod_stack.o pfring_hw_filtering.o pfring_hw_timestamp.o pfring_mod_sysdig.o `ar t ../nbpf/libnbpf.a | grep -F .o | tr ' ' ' '`
ranlib libpfring.a
=*= making library libpfring.so =*=
arm-openwrt-linux-uclibcgnueabi-gcc -Wl,-soname,libpfring.so.1 -g -shared pfring.o pfring_mod.o pfring_utils.o pfring_mod_stack.o pfring_hw_filtering.o pfring_hw_timestamp.o pfring_mod_sysdig.o `ar t ../nbpf/libnbpf.a | grep -F .o | tr ' ' ' '` -lpthread -lrt -ldl -lnl-genl-3 -lnl-3 -o libpfring.so
/home/pon/qca/qca.git/qsdk/staging_dir/toolchain-arm_cortex-a7_gcc-4.8-linaro_uClibc-1.0.14_eabi/lib/gcc/arm-openwrt-linux-uclibcgnueabi/4.8.3/../../../../arm-openwrt-linux-uclibcgnueabi/bin/ld: nbpf_mod_rdif.o: Relocations in generic ELF (EM: 3)
/home/pon/qca/qca.git/qsdk/staging_dir/toolchain-arm_cortex-a7_gcc-4.8-linaro_uClibc-1.0.14_eabi/lib/gcc/arm-openwrt-linux-uclibcgnueabi/4.8.3/../../../../arm-openwrt-linux-uclibcgnueabi/bin/ld: nbpf_mod_rdif.o: Relocations in generic ELF (EM: 3)
nbpf_mod_rdif.o: error adding symbols: File in wrong format
collect2: error: ld returned 1 exit status
make[5]: *** [libpfring.so] Error 1
make[5]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/userland/lib'
make[4]: *** [libpfring] Error 2
make[4]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/userland'
make[3]: *** [all] Error 2
make[3]: Leaving directory `/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring'
make[2]: *** [/home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/.built] Error 2
make[2]: Leaving directory `/home/pon/qca/qca.git/qsdk/package/utils/pfring'
make[1]: *** [package/utils/pfring/compile] Error 2
make[1]: Leaving directory `/home/pon/qca/qca.git/qsdk'
make: *** [package/utils/pfring/compile] 错误 2
原因：
file pfring/userland/lib/nbpf_mod_rdif.o，
nbpf_mod_rdif.o: ELF 32-bit LSB relocatable, Intel 80386, version 1 (SYSV), not strippe
说明没有按照交叉编译编译生成nbpf_mod_rdif.o
解决：
修改/pfring/src/userland/nbpf/Makefile文件“
CC=arm-openwrt-linux-uclibcgnueabi-gcc
错误6
编译成功后，将其拷贝到/usr/lib下会出现下面错误：
install -d -m0755 /home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/ipkg-ipq806x/pfring/usr/lib
cp -fpR /home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/userland/lib/*.so /home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/ipkg-ipq806x/pfring/usr/lib
find /home/...../build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/pfring/ipkg-ipq806x/pfring -name 'CVS' -o -name '.svn' -o -name '.#*' -o -name '*~'| xargs -r rm -rf
Package pfring is missing dependencies for the following libraries:
libnl-3.so.200
libnl-genl-3.so.200
libpthread.so.1
librt.so.1
解决方法：
在/usr/lib下有libnl-3.so.200，libnl-genl-3.so.200，libpthread.so.1，librt.so.1，但需要建立软连接；
这四个文件存在于文件系统中，如下：
build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/root-ipq806x/usr/lib/libnl-3.so.200
uild_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/root-ipq806x/usr/lib/libnl-genl-3.so.200
build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/root-ipq806x/lib/libpthread.so.1
build_dir/target-arm_cortex-a7_uClibc-1.0.14_eabi/root-ipq806x/lib/librt.so.1
将其拷贝到下面文件下：
/package/utils/pfring/src/userland/deplib，
并修改
package/utils/pfring/Makefile,增加下面代码：
$(CP) $(PKG_BUILD_DIR)/userland/deplib/* $(1)/usr/lib