c - ARMv5 上的 libsodium 段错误

Question

我可以在 Ubuntu 中很好地使用 libsodium 1.0.7，但是在尝试将 libsodium 库交叉编译为 armv5 架构时似乎存在一些问题 (armv5tejl-unknown-linux-gnueabihf) .我使用了 ./configure --host=armv5tejl-unknown-linux-gnueabihf 然后 make DESTDIR=/home/myself/ARM/。

所有文件都生成良好( header 和静态和共享库文件)，我可以编译和链接一个小的测试 C 程序，然后在我的 ARMv5 目标上执行时生成一个段错误(工具链和一切都很好，一切否则我编译和链接不使用 libsodium 在我的 ARM 机器上运行得很好):

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "sodium.h"
int main()
{
  printf("sodium_init()=%d\n",sodium_init()); // Fine, = 0
  unsigned char pbk[crypto_box_PUBLICKEYBYTES];
  unsigned char sbk[crypto_box_SECRETKEYBYTES];
  crypto_box_keypair(pbk,sbk); // <-- Segmentation fault.
}

我还在 https://download.libsodium.org/doc/installation/index.html 尝试了 ARM 指令的官方交叉编译。但由于缺少 nosys.specs 文件，配置失败。有没有什么地方可以下载这个(我已经用 goggle 了，它似乎必须专门为 libsodium 包生成)？

Answer 1

我在这里借助一些帮助设法解决了它:github.com/jedisct1/libsodium/issues/331 –提亚斯

Right, I finally managed to make it run on my ARMv5 target by doing the following, many thanks for pointing me to the ARM toolchain that contained the nosys.spec & libnosys.a files :

• Downloaded ARM toolchain gcc-arm-none-eabi-4_9-2015q3-20150921-linux.tar.bz2 from https://launchpad.net/gcc-arm-embedded
• Downloaded libsodium-1.0.7 from https://download.libsodium.org/libsodium/releases/

Note: This is for making a static libsodium.a

Example below assuming home folder = /home/user

tar xvjf gcc-arm-none-eabi-4_9-2015q3-20150921-linux.tar.bz2
tar xvzf libsodium-1.0.7.tar.gz
cp ./gcc-arm-none-eabi-4_9-2015q3/arm-none-eabi/lib/nosys.spec ./libsodium-1.0.7/
cp ./gcc-arm-none-eabi-4_9-2015q3/arm-none-eabi/lib/libnosys.a ./libsodium-1.0.7/ 

Folder gcc-arm-none-eabi-4_9-can be deleted at this point.

cd ./libsodium-1.0.7/
mkdir ARMv5
export LDFLAGS='-static -g --specs=nosys.specs -L/home/user/libsodium-1.0.7/ -lnosys -lc'
./configure --host=armv5tejl-unknown-linux-gnueabihf --enable-static --prefix=/home/user/libsodium-1.0.7/ARMv5/
make DESTDIR=/home/user/libsodium-1.0.7/ARMv5/ 

Key discoveries for me :

• Hint from jedisct1 where to get the ARM toolchain containing both the nosys.spec and libnosys.a files.
• Found out to add linker flag -lc to make libsodium with libc (contaning __libc_start_main, abort, __libc_csu_fini and __libc_csu_init)