Add support for Android compressed rel/rela sections

examples/android_rel.rs

@@ -0,0 +1,37 @@
+use elf::{ abi, endian, ElfBytes, relocation::aps2};
+
+fn main() {
+    let path = std::path::Path::new("sample-objects/android_cpp.arm.so");
+    let raw_file = std::fs::read(path).unwrap();
+    let file =
+        ElfBytes::<endian::AnyEndian>::minimal_parse(raw_file.as_slice()).expect("parse elf file");
+
+    let rel = file.dynamic().unwrap().unwrap().iter().find(|d| d.d_tag == abi::DT_ANDROID_REL).unwrap();
+    let rel_sz = file.dynamic().unwrap().unwrap().iter().find(|d| d.d_tag == abi::DT_ANDROID_RELSZ).unwrap();
+    let rel_offset = addr_to_offset(&file, rel.d_ptr()).unwrap();
+
+    let rel_data = raw_file.as_slice().get(rel_offset..rel_offset+rel_sz.d_val() as usize).unwrap();
+
+    let android_rel = aps2::AndroidRelIterator::new(file.ehdr.class, rel_data).unwrap();
+
+    for rel in android_rel{
+        match rel{
+            Ok(rel) => {
+                println!("type: {}, sym: {}, offset: {}", rel.r_type, rel.r_sym, rel.r_offset);
+            },
+            Err(e) => {
+                println!("error: {:?}", e);
+                break;
+            }
+        }
+    }
+}
+fn addr_to_offset<E:endian::EndianParse>(elf: &elf::ElfBytes<E>, addr: u64) -> Option<usize> {
+    elf.segments().and_then(|segs| {
+        segs.iter().find(|item| {
+            item.p_type == abi::PT_LOAD && item.p_vaddr <= addr && addr < item.p_vaddr + item.p_memsz
+        })
+    }).map(|seg| {
+        (addr - seg.p_vaddr + seg.p_offset) as usize
+    })
+}

examples/android_rela.rs

@@ -0,0 +1,24 @@
+use elf::{ abi, endian, ElfBytes};
+
+fn main() {
+    let path = std::path::Path::new("sample-objects/android_cpp.aarch64.so");
+    let raw_file = std::fs::read(path).unwrap();
+    let file =
+        ElfBytes::<endian::AnyEndian>::minimal_parse(raw_file.as_slice()).expect("parse elf file");
+
+    let rel_sh = file.section_headers().unwrap().iter().find(|seg|{seg.sh_type == abi::SHT_ANDROID_RELA}).unwrap();
+
+    let android_rela = file.section_date_as_android_relas(&rel_sh).unwrap();
+
+    for rela in android_rela{
+        match rela{
+            Ok(rela) => {
+                println!("type: {}, sym: {}, offset: {}, addend: {}", rela.r_type, rela.r_sym, rela.r_offset, rela.r_addend);
+            },
+            Err(e) => {
+                println!("error: {:?}", e);
+                break;
+            }
+        }
+    }
+}