build: Add AFL++ fuzzing support (#351)

Author: anfedotoff

Diff for: fuzz-afl/Cargo.toml

@@ -0,0 +1,27 @@
+[package]
+name = "goblin-fuzz-afl"
+version = "0.0.1"
+authors = ["Andrey Fedotov <[email protected]>"]
+edition = "2018"
+publish = false
+
+[dependencies.goblin]
+path = ".."
+
+[dependencies]
+afl = "*"
+
+# Prevent this from interfering with workspaces
+[workspace]
+members = ["."]
+
+[profile.release]
+debug = true
+
+[[bin]]
+name = "afl_parse"
+path = "fuzz_targets/afl_parse.rs"
+
+[[bin]]
+name = "afl_parse_elf"
+path = "fuzz_targets/afl_parse_elf.rs"

Diff for: fuzz-afl/fuzz_targets/afl_parse.rs

@@ -0,0 +1,8 @@
+#[macro_use]
+extern crate afl;
+
+fn main() {
+    fuzz!(|data: &[u8]| {
+        let _ = goblin::Object::parse(data);
+    });
+}

Diff for: fuzz-afl/fuzz_targets/afl_parse_elf.rs

@@ -0,0 +1,26 @@
+#[macro_use]
+extern crate afl;
+
+fn main() {
+    fuzz!(|data: &[u8]| {
+        if let Ok(elf) = goblin::elf::Elf::parse(data) {
+            for section_header in &elf.section_headers {
+                let _ = elf.shdr_strtab.get_at(section_header.sh_name);
+            }
+
+            for _relocation in &elf.dynrels {}
+
+            if let Some(mut it) = elf.iter_note_headers(data) {
+                while let Some(Ok(_a)) = it.next() {}
+            }
+
+            if let Some(mut it) = elf.iter_note_sections(data, None) {
+                while let Some(Ok(_a)) = it.next() {}
+            }
+
+            if let Some(mut it) = elf.iter_note_sections(data, Some("x")) {
+                while let Some(Ok(_a)) = it.next() {}
+            }
+        }
+    });
+}

Diff for: fuzz/fuzz_targets/parse_elf.rs

@@ -4,7 +4,7 @@ use libfuzzer_sys::fuzz_target;
 fuzz_target!(|data: &[u8]| {
     if let Ok(elf) = goblin::elf::Elf::parse(data) {
         for section_header in &elf.section_headers {
-            let _ = elf.shdr_strtab.get(section_header.sh_name);
+            let _ = elf.shdr_strtab.get_at(section_header.sh_name);
         }
 
         for _relocation in &elf.dynrels {}