Bug 1847098 - Add version number of so files (#103)

* Bug 1847098 - Add version number of so files

* Simplify

The original code would have paniced on non-utf8 paths, and would fail to return any version components if a single one failed to be parsed as a number.

The new code will now gracefully fail if the filename (the rest of the path is inconsequential) is non-utf8, and now tries to handle as many version components as it can, including partial parsing of mixed alphanumeric components such as, eg 2rc5 (which was aready a test case) would be parsed as `25`

---------

Co-authored-by: Alexandre Lissy <lissyx@lissyx.dyndns.org>
Co-authored-by: Jake Shadle <jake.shadle@embark-studios.com>

src/linux/maps_reader.rs

@@ -303,7 +303,44 @@ impl MappingInfo {
         Ok(soname.to_string())
     }
 
-    pub fn get_mapping_effective_path_and_name(&self) -> Result<(PathBuf, String)> {
+    /// Attempts to retrieve the .so version of the elf via its filename as a
+    /// `(major, minor, release)` triplet
+    fn elf_file_so_version(&self) -> (u32, u32, u32) {
+        const DEF: (u32, u32, u32) = (0, 0, 0);
+        let Some(so_name) = self.name.as_deref() else {
+            return DEF;
+        };
+        let Some(filename) = std::path::Path::new(so_name).file_name() else {
+            return DEF;
+        };
+
+        // Avoid an allocation unless the string contains non-utf8
+        let filename = filename.to_string_lossy();
+
+        let Some((_, version)) = filename.split_once(".so.") else {
+            return DEF;
+        };
+
+        let mut triplet = [0, 0, 0];
+
+        for (so, trip) in version.split('.').zip(triplet.iter_mut()) {
+            // In some cases the release/patch version is alphanumeric (eg. '2rc5'),
+            // so try to parse as much as we can rather than completely ignoring
+            for digit in so
+                .chars()
+                .filter_map(|c: char| c.is_ascii_digit().then_some(c as u8 - b'0'))
+            {
+                *trip *= 10;
+                *trip += digit as u32;
+            }
+        }
+
+        (triplet[0], triplet[1], triplet[2])
+    }
+
+    pub fn get_mapping_effective_path_name_and_version(
+        &self,
+    ) -> Result<(PathBuf, String, (u32, u32, u32))> {
         let mut file_path = PathBuf::from(self.name.clone().unwrap_or_default());
 
         // Tools such as minidump_stackwalk use the name of the module to look up
@@ -321,7 +358,7 @@ impl MappingInfo {
                 .file_name()
                 .map(|s| s.to_string_lossy().into_owned())
                 .unwrap_or_default();
-            return Ok((file_path, file_name));
+            return Ok((file_path, file_name, self.elf_file_so_version()));
         };
 
         if self.is_executable() && self.offset != 0 {
@@ -337,7 +374,7 @@ impl MappingInfo {
             file_path.set_file_name(&file_name);
         }
 
-        Ok((file_path, file_name))
+        Ok((file_path, file_name, self.elf_file_so_version()))
     }
 
     pub fn is_contained_in(&self, user_mapping_list: &MappingList) -> bool {
@@ -628,13 +665,48 @@ a4840000-a4873000 rw-p 09021000 08:12 393449     /data/app/org.mozilla.firefox-1
         );
         assert_eq!(mappings.len(), 1);
 
-        let (file_path, file_name) = mappings[0]
-            .get_mapping_effective_path_and_name()
+        let (file_path, file_name, _version) = mappings[0]
+            .get_mapping_effective_path_name_and_version()
             .expect("Couldn't get effective name for mapping");
         assert_eq!(file_name, "libmozgtk.so");
         assert_eq!(file_path, PathBuf::from("/home/martin/Documents/mozilla/devel/mozilla-central/obj/widget/gtk/mozgtk/gtk3/libmozgtk.so"));
     }
 
+    #[test]
+    fn test_elf_file_so_version() {
+        let mappings = get_mappings_for(
+            "\
+7f877ab9f000-7f877aba0000 rw-p 0001f000 00:1b 100457459                  /home/alex/bin/firefox/libmozsandbox.so
+7f877ae65000-7f877ae68000 rw-p 00265000 00:1b 90432393                   /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.32
+7f877ae76000-7f877ae77000 rw-p 0000a000 00:1b 90443112                   /usr/lib/x86_64-linux-gnu/libcairo-gobject.so.2.11800.0
+7f877ae7c000-7f877ae8c000 r--p 00000000 00:1b 93439971                   /usr/lib/x86_64-linux-gnu/libm.so.6
+7f877af70000-7f877af71000 rw-p 00003000 00:1b 93439980                   /usr/lib/x86_64-linux-gnu/libpthread.so.0
+7f877af78000-7f877af79000 rw-p 00005000 00:1b 90423049                   /usr/lib/x86_64-linux-gnu/libgmodule-2.0.so.0.7800.0
+7f877ae7c000-7f877ae8c000 rw-p 00000000 00:1b 93439971                   /usr/lib/x86_64-linux-gnu/libabsl_time_zone.so.20220623.0.0
+7f877ae7c000-7f877ae8c000 rw-p 00000000 00:1b 93439971                   /usr/lib/x86_64-linux-gnu/libdbus-1.so.3.34.2rc5
+7f877ae7c000-7f877ae8c000 rw-p 00000000 00:1b 93439971                   /usr/lib/x86_64-linux-gnu/libtoto.so.AAA",
+            0x7ffe091bf000,
+        );
+        assert_eq!(mappings.len(), 9);
+
+        let expected = [
+            (0, 0, 0),
+            (6, 0, 32),
+            (2, 11800, 0),
+            (6, 0, 0),
+            (0, 0, 0),
+            (0, 7800, 0),
+            (20220623, 0, 0),
+            (3, 34, 25),
+            (0, 0, 0),
+        ];
+
+        for (i, (map, exp)) in mappings.into_iter().zip(expected).enumerate() {
+            let version = map.elf_file_so_version();
+            assert_eq!(version, exp, "{i}");
+        }
+    }
+
     #[test]
     fn test_whitespaces_in_name() {
         let mappings = get_mappings_for(

src/linux/sections/mappings.rs

@@ -83,16 +83,24 @@ fn fill_raw_module(
         sig_section.location()
     };
 
-    let (file_path, _) = mapping
-        .get_mapping_effective_path_and_name()
+    let (file_path, _, (major, minor, release)) = mapping
+        .get_mapping_effective_path_name_and_version()
         .map_err(|e| errors::SectionMappingsError::GetEffectivePathError(mapping.clone(), e))?;
     let name_header = write_string_to_location(buffer, file_path.to_string_lossy().as_ref())?;
 
-    Ok(MDRawModule {
+    let mut raw_module = MDRawModule {
         base_of_image: mapping.start_address as u64,
         size_of_image: mapping.size as u32,
         cv_record,
         module_name_rva: name_header.rva,
         ..Default::default()
-    })
+    };
+
+    raw_module.version_info.signature = format::VS_FFI_SIGNATURE;
+    raw_module.version_info.struct_version = format::VS_FFI_STRUCVERSION;
+    raw_module.version_info.file_version_hi = major;
+    raw_module.version_info.file_version_lo = minor;
+    raw_module.version_info.product_version_hi = release;
+
+    Ok(raw_module)
 }