Add section to segment mapping

fjeremic · Jan 17, 2020 · 854b845 · 854b845
1 parent 34e5dc0
commit 854b845
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Showing 4 changed files with 74 additions and 2 deletions.
diff --git a/BinaryTools.Elf.Tests/TestElfSegment.cs b/BinaryTools.Elf.Tests/TestElfSegment.cs
@@ -136,5 +136,65 @@ public void TestAlignment()
             Assert.Equal(0x8UL, elfFile.Segments[4].Alignment);
             Assert.Equal(0x4UL, elfFile.Segments[5].Alignment);
         }
+
+        [Fact]
+        public void TestSectionToSegmentMapping()
+        {
+            var stream = new FileStream("Binaries/base32", FileMode.Open, FileAccess.Read);
+            var reader = new EndianBinaryReader(stream, EndianBitConverter.NativeEndianness);
+            ElfFile elfFile = ElfFile.ReadElfFile(reader);
+
+            Assert.Equal(0, elfFile.Segments[0].Sections.Count);
+            Assert.Equal(1, elfFile.Segments[1].Sections.Count);
+            Assert.Equal(elfFile.Sections[1], elfFile.Segments[1].Sections[0]);
+
+            Assert.Equal(18, elfFile.Segments[2].Sections.Count);
+            Assert.Equal(elfFile.Sections[1], elfFile.Segments[2].Sections[0]);
+            Assert.Equal(elfFile.Sections[2], elfFile.Segments[2].Sections[1]);
+            Assert.Equal(elfFile.Sections[3], elfFile.Segments[2].Sections[2]);
+            Assert.Equal(elfFile.Sections[4], elfFile.Segments[2].Sections[3]);
+            Assert.Equal(elfFile.Sections[5], elfFile.Segments[2].Sections[4]);
+            Assert.Equal(elfFile.Sections[6], elfFile.Segments[2].Sections[5]);
+            Assert.Equal(elfFile.Sections[7], elfFile.Segments[2].Sections[6]);
+            Assert.Equal(elfFile.Sections[8], elfFile.Segments[2].Sections[7]);
+            Assert.Equal(elfFile.Sections[9], elfFile.Segments[2].Sections[8]);
+            Assert.Equal(elfFile.Sections[10], elfFile.Segments[2].Sections[9]);
+            Assert.Equal(elfFile.Sections[11], elfFile.Segments[2].Sections[10]);
+            Assert.Equal(elfFile.Sections[12], elfFile.Segments[2].Sections[11]);
+            Assert.Equal(elfFile.Sections[13], elfFile.Segments[2].Sections[12]);
+            Assert.Equal(elfFile.Sections[14], elfFile.Segments[2].Sections[13]);
+            Assert.Equal(elfFile.Sections[15], elfFile.Segments[2].Sections[14]);
+            Assert.Equal(elfFile.Sections[16], elfFile.Segments[2].Sections[15]);
+            Assert.Equal(elfFile.Sections[17], elfFile.Segments[2].Sections[16]);
+            Assert.Equal(elfFile.Sections[18], elfFile.Segments[2].Sections[17]);
+
+            Assert.Equal(8, elfFile.Segments[3].Sections.Count);
+            Assert.Equal(elfFile.Sections[19], elfFile.Segments[3].Sections[0]);
+            Assert.Equal(elfFile.Sections[20], elfFile.Segments[3].Sections[1]);
+            Assert.Equal(elfFile.Sections[21], elfFile.Segments[3].Sections[2]);
+            Assert.Equal(elfFile.Sections[22], elfFile.Segments[3].Sections[3]);
+            Assert.Equal(elfFile.Sections[23], elfFile.Segments[3].Sections[4]);
+            Assert.Equal(elfFile.Sections[24], elfFile.Segments[3].Sections[5]);
+            Assert.Equal(elfFile.Sections[25], elfFile.Segments[3].Sections[6]);
+            Assert.Equal(elfFile.Sections[26], elfFile.Segments[3].Sections[7]);
+
+            Assert.Equal(1, elfFile.Segments[4].Sections.Count);
+            Assert.Equal(elfFile.Sections[22], elfFile.Segments[4].Sections[0]);
+
+            Assert.Equal(2, elfFile.Segments[5].Sections.Count);
+            Assert.Equal(elfFile.Sections[2], elfFile.Segments[5].Sections[0]);
+            Assert.Equal(elfFile.Sections[3], elfFile.Segments[5].Sections[1]);
+
+            Assert.Equal(1, elfFile.Segments[6].Sections.Count);
+            Assert.Equal(elfFile.Sections[17], elfFile.Segments[6].Sections[0]);
+
+            Assert.Equal(0, elfFile.Segments[7].Sections.Count);
+            Assert.Equal(5, elfFile.Segments[8].Sections.Count);
+            Assert.Equal(elfFile.Sections[19], elfFile.Segments[8].Sections[0]);
+            Assert.Equal(elfFile.Sections[20], elfFile.Segments[8].Sections[1]);
+            Assert.Equal(elfFile.Sections[21], elfFile.Segments[8].Sections[2]);
+            Assert.Equal(elfFile.Sections[22], elfFile.Segments[8].Sections[3]);
+            Assert.Equal(elfFile.Sections[23], elfFile.Segments[8].Sections[4]);
+        }
     }
 }
diff --git a/BinaryTools.Elf/ElfFile.cs b/BinaryTools.Elf/ElfFile.cs
@@ -127,8 +127,8 @@ public static ElfFile ReadElfFile(BinaryReader reader)
                         }
                 }
 
-                var segments = new ElfProgramHeaderTable(reader, header);
                 var sections = new ElfSectionHeaderTable(reader, header);
+                var segments = new ElfProgramHeaderTable(reader, header, sections);
 
                 return new ElfFile(header, segments, sections);
             }

diff --git a/BinaryTools.Elf/ElfProgramHeaderTable.cs b/BinaryTools.Elf/ElfProgramHeaderTable.cs
@@ -2,6 +2,7 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.IO;
+using System.Linq;
 
 namespace BinaryTools.Elf
 {
@@ -56,7 +57,7 @@ public Int32 Count
         /// <param name="header">
         /// The ELF header used to extract the metadata about this program header table.
         /// </param>
-        internal ElfProgramHeaderTable(BinaryReader reader, ElfHeader header)
+        internal ElfProgramHeaderTable(BinaryReader reader, ElfHeader header, ElfSectionHeaderTable sections)
         {
             // Initialize all segments
             for (var i = 0; i < header.ProgramHeaderEntryCount; i++)
@@ -83,6 +84,8 @@ internal ElfProgramHeaderTable(BinaryReader reader, ElfHeader header)
                         }
                 }
 
+                segment.Sections = sections.Where(s => s.Address >= segment.VirtualAddress && s.Address < segment.VirtualAddress + segment.MemorySize).ToList().AsReadOnly();
+
                 segments.Add(segment);
             }
         }

diff --git a/BinaryTools.Elf/ElfSegment.cs b/BinaryTools.Elf/ElfSegment.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 
 namespace BinaryTools.Elf
 {
@@ -130,5 +131,13 @@ public ElfSegmentFlags Flags
         {
             get; protected set;
         }
+
+        /// <summary>
+        /// Gets a list of sections mapped to this segment.
+        /// </summary>
+        public IReadOnlyList<ElfSection> Sections
+        {
+            get; internal set;
+        }
     }
 }