1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130

use goblin::mach::{cputype::get_arch_from_flag, Mach, MultiArch};

use crate::error::Error;

/// Mach-O fat binary reader
#[derive(Debug)]
pub struct FatReader<'a> {
    buffer: &'a [u8],
    fat: MultiArch<'a>,
}

impl<'a> FatReader<'a> {
    /// Parse a Mach-O FAT binary from a buffer
    pub fn new(buffer: &'a [u8]) -> Result<Self, Error> {
        match Mach::parse(buffer)? {
            Mach::Fat(fat) => Ok(Self { buffer, fat }),
            Mach::Binary(_) => Err(Error::NotFatBinary),
        }
    }

    /// Extract thin binary by arch name
    pub fn extract(&self, arch_name: &str) -> Option<&'a [u8]> {
        if let Some((cpu_type, _cpu_subtype)) = get_arch_from_flag(arch_name) {
            return self
                .fat
                .find_cputype(cpu_type)
                .unwrap_or_default()
                .map(|arch| arch.slice(self.buffer));
        }
        None
    }
}

impl<'a> std::ops::Deref for FatReader<'a> {
    type Target = MultiArch<'a>;

    fn deref(&self) -> &Self::Target {
        &self.fat
    }
}

impl<'a> std::ops::DerefMut for FatReader<'a> {
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.fat
    }
}

#[cfg(test)]
mod test {
    use std::fs;

    use goblin::Object;

    use super::FatReader;
    use crate::error::Error;

    #[test]
    fn test_fat_reader_dylib() {
        let buf = fs::read("tests/fixtures/simplefat.dylib").unwrap();
        let reader = FatReader::new(&buf);
        assert!(reader.is_ok());
    }

    #[test]
    fn test_fat_reader_exe() {
        let buf = fs::read("tests/fixtures/simplefat").unwrap();
        let reader = FatReader::new(&buf).unwrap();
        assert_eq!(2, reader.narches);

        let buf = fs::read("tests/fixtures/hellofat").unwrap();
        let reader = FatReader::new(&buf).unwrap();
        assert_eq!(3, reader.narches);
    }

    #[test]
    fn test_fat_reader_ar() {
        let buf = fs::read("tests/fixtures/simplefat.a").unwrap();
        let reader = FatReader::new(&buf);
        assert!(reader.is_ok());
    }

    #[test]
    fn test_fat_reader_not_fat() {
        let buf = fs::read("tests/fixtures/thin_x86_64").unwrap();
        let reader = FatReader::new(&buf);
        assert!(reader.is_err());
        assert!(matches!(reader.unwrap_err(), Error::NotFatBinary));

        let buf = fs::read("tests/fixtures/thin_arm64").unwrap();
        let reader = FatReader::new(&buf);
        assert!(reader.is_err());
        assert!(matches!(reader.unwrap_err(), Error::NotFatBinary));
    }

    #[test]
    fn test_fat_reader_extract_dylib() {
        let buf = fs::read("tests/fixtures/simplefat.dylib").unwrap();
        let reader = FatReader::new(&buf).unwrap();
        let x86_64 = reader.extract("x86_64").unwrap();
        let x86_64_obj = Object::parse(x86_64).unwrap();
        assert!(matches!(x86_64_obj, Object::Mach(_)));
        let arm64 = reader.extract("arm64").unwrap();
        let arm64_obj = Object::parse(arm64).unwrap();
        assert!(matches!(arm64_obj, Object::Mach(_)));
    }

    #[test]
    fn test_fat_reader_extract_exe() {
        let buf = fs::read("tests/fixtures/simplefat").unwrap();
        let reader = FatReader::new(&buf).unwrap();
        let x86_64 = reader.extract("x86_64").unwrap();
        let x86_64_obj = Object::parse(x86_64).unwrap();
        assert!(matches!(x86_64_obj, Object::Mach(_)));
        let arm64 = reader.extract("arm64").unwrap();
        let arm64_obj = Object::parse(arm64).unwrap();
        assert!(matches!(arm64_obj, Object::Mach(_)));
    }

    #[test]
    fn test_fat_reader_extract_ar() {
        let buf = fs::read("tests/fixtures/simplefat.a").unwrap();
        let reader = FatReader::new(&buf).unwrap();
        let x86_64 = reader.extract("x86_64").unwrap();
        let x86_64_obj = Object::parse(x86_64).unwrap();
        assert!(matches!(x86_64_obj, Object::Archive(_)));
        let arm64 = reader.extract("arm64").unwrap();
        let arm64_obj = Object::parse(arm64).unwrap();
        assert!(matches!(arm64_obj, Object::Archive(_)));
    }
}