Linking with versioned shared library in Android NDK

I had the same problem on building libwebsockets for Android, which needs to link with OpenSSL. I use libssl.so as example. You should do the same for related .so files.

Before: huiying@huiying-PORTEGE-R835:~$ objdump -p libssl.so | grep so libssl.so: file format elf32-little NEEDED libcrypto.so.1.0.0 NEEDED libdl.so NEEDED libc.so SONAME libssl.so.1.0.0 After huiying@huiying-PORTEGE-R835:~$ rpl -R -e .so.1.0.0 "_1_0_0.so" libssl.so Replacing ".so.1.0.0" with "_1_0_0.so" (case sensitive) (partial words matched) . A Total of 2 matches replaced in 1 file searched. huiying@huiying-PORTEGE-R835:~$ objdump -p libssl.so | grep so libssl.so: file format elf32-little NEEDED libcrypto_1_0_0.so NEEDED libdl.so NEEDED libc.so SONAME libssl_1_0_0.so And don't forget to change file name "libssl.so" to "libssl_1_0_0.so".

The hack works. I have running Android app to prove it. See my rant at http://computervisionandjava.blogspot.com/2015/05/trouble-with-versioned-shared-libraries.html.

It seems android has an issue with loading versioned libraries.The issue at hand was because of library so-name in my case libcrypto.so.1.0.0. Even if you rename the library and try to load it as a prebuilt shared library in an android make file it fails.( It has to be because the library name is somehow embedded in the file. And any library that links with it expects to be linked with a library of with the same name )

I hope there are other ways out there when it comes to handling libraries with version names in android.

For now I am evading the problem all together by using static libraries of openssl and linking them with my own shared library.

Year 2014 and still no support for versioned shared libs. So I made a script to patch SONAME. Just point the script to input dir where all versioned libs placed. Then check output dir "unver".

#!/bin/bash DIR="$1" if [ "$DIR" == "" ]; then echo "Usage: fix-soname.sh <target dir>" exit fi if [ ! -d $DIR ]; then echo "Not found: $DIR" exit fi OUT="$DIR/unver" echo "Input=$DIR" echo "Output=$OUT" CWD=$(pwd) cd $DIR # prep dirs mkdir -p $OUT rm -f -R $OUT/* # rename libs and copy to out dir find "$DIR" -type f -name '*.so*' | while read FILE; do NAME=$(basename "$FILE") SONAME=$NAME while read SYMLINK; do X=$(basename "$SYMLINK") #echo "$X (${#X}) -> $NAME (${#NAME})" if [ "${#X}" -lt "${#SONAME}" ]; then SONAME=$X fi done<<EOT `find -L $DIR -samefile $FILE` EOT #echo $SONAME cp -f $SONAME $OUT/ done # patch libs in out dir find "$OUT" -type f -name '*.so*' | while read FILE; do # get file name without path NAME=$(basename "$FILE") # extract SONAME from shared lib SONAME=`readelf -d $FILE | grep '(SONAME)' | grep -P '(?<=\[)(lib.*?)(?=\])' -o` #echo "$NAME [$SONAME]" # patch SONAME if required if [ "$NAME" != "$SONAME" ]; then L1=${#NAME} L2=${#SONAME} LDIFF=$((L2-L1)) #echo "$NAME [$SONAME] ($LDIFF)" if [ "$LDIFF" -gt "0" ]; then SONEW=$NAME for (( c=1; c<=$LDIFF; c++ )); do SONEW+="\x00" done echo "$NAME [$SONAME] -> $SONEW ($LDIFF)" rpl -R -e "$SONAME" "$SONEW" $OUT fi fi done cd $CWD 

In 2024, Android 14 still doesn't support versioned objects in the form of *.so.x.x.x because it forces module_name+'.so'==object_name.

I was able to follow the most upvoted as of now except that rpl does not do it for binary file in 2024 and searching and replacing via a text editor messes up the ELF format.

I used patchelf to do it and it works great. github

Sample commands for openssl, libssl.so.1.1 and libcrypto.so.1.1 were:

 2078 objdump -p lib* | grep so 2079 patchelf --set-soname libssl_1_1.so libssl.so.1.1 2080 patchelf --set-soname libcrypto_1_1.so libcrypto.so.1.1 2081 patchelf --replace-needed libcrypto.so.1.1 libcrypto_1_1.so 

Again, don't forget to rename the file to match the SONAME.

For other library, the shared object should be inspected before using patchelf to understand what needs to be changed.