+use libc::{c_int, c_ulong, c_void};
+use std::ffi::{CStr, CString};
+use std::cmp::Ordering;
+use std::{fmt, ptr};
+
+use ffi;
+use ssl::error::SslError;
+
+pub struct BigNum(*mut ffi::BIGNUM);
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub enum RNGProperty {
+    MsbMaybeZero = -1,
+    MsbOne = 0,
+    TwoMsbOne = 1,
+}
+
+macro_rules! with_ctx(
+    ($name:ident, $action:block) => ({
+        let $name = ffi::BN_CTX_new();
+        if ($name).is_null() {
+            Err(SslError::get())
+        } else {
+            let r = $action;
+            ffi::BN_CTX_free($name);
+            r
+        }
+    });
+);
+
+macro_rules! with_bn(
+    ($name:ident, $action:block) => ({
+        let tmp = BigNum::new();
+        match tmp {
+            Ok($name) => {
+                if $action {
+                    Ok($name)
+                } else {
+                    Err(SslError::get())
+                }
+            },
+            Err(err) => Err(err),
+        }
+    });
+);
+
+macro_rules! with_bn_in_ctx(
+    ($name:ident, $ctx_name:ident, $action:block) => ({
+        let tmp = BigNum::new();
+        match tmp {
+            Ok($name) => {
+                let $ctx_name = ffi::BN_CTX_new();
+                if ($ctx_name).is_null() {
+                    Err(SslError::get())
+                } else {
+                    let r =
+                        if $action {
+                            Ok($name)
+                        } else {
+                            Err(SslError::get())
+                        };
+                    ffi::BN_CTX_free($ctx_name);
+                    r
+                }
+            },
+            Err(err) => Err(err),
+        }
+    });
+);
+
+impl BigNum {
+    pub fn new() -> Result<BigNum, SslError> {
+        unsafe {
+            ffi::init();
+
+            let v = try_ssl_null!(ffi::BN_new());
+            Ok(BigNum(v))
+        }
+    }
+
+    pub fn new_from(n: u64) -> Result<BigNum, SslError> {
+        BigNum::new().and_then(|v| unsafe {
+            try_ssl!(ffi::BN_set_word(v.raw(), n as c_ulong));
+            Ok(v)
+        })
+    }
+
+    pub fn from_dec_str(s: &str) -> Result<BigNum, SslError> {
+        BigNum::new().and_then(|v| unsafe {
+            let c_str = CString::new(s.as_bytes()).unwrap();
+            try_ssl!(ffi::BN_dec2bn(v.raw_ptr(), c_str.as_ptr()));
+            Ok(v)
+        })
+    }
+
+    pub fn from_hex_str(s: &str) -> Result<BigNum, SslError> {
+        BigNum::new().and_then(|v| unsafe {
+            let c_str = CString::new(s.as_bytes()).unwrap();
+            try_ssl!(ffi::BN_hex2bn(v.raw_ptr(), c_str.as_ptr()));
+            Ok(v)
+        })
+    }
+
+    pub fn new_from_slice(n: &[u8]) -> Result<BigNum, SslError> {
+        BigNum::new().and_then(|v| unsafe {
+            try_ssl_null!(ffi::BN_bin2bn(n.as_ptr(), n.len() as c_int, v.raw()));
+            Ok(v)
+        })
+    }
+
+    pub fn checked_sqr(&self) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_sqr(r.raw(), self.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_nnmod(&self, n: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_nnmod(r.raw(), self.raw(), n.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_mod_add(&self, a: &BigNum, n: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_mod_add(r.raw(), self.raw(), a.raw(), n.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_mod_sub(&self, a: &BigNum, n: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_mod_sub(r.raw(), self.raw(), a.raw(), n.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_mod_mul(&self, a: &BigNum, n: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_mod_mul(r.raw(), self.raw(), a.raw(), n.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_mod_sqr(&self, n: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_mod_sqr(r.raw(), self.raw(), n.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_exp(&self, p: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_exp(r.raw(), self.raw(), p.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_mod_exp(&self, p: &BigNum, n: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_mod_exp(r.raw(), self.raw(), p.raw(), n.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_mod_inv(&self, n: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { !ffi::BN_mod_inverse(r.raw(), self.raw(), n.raw(), ctx).is_null() })
+        }
+    }
+
+    pub fn add_word(&mut self, w: c_ulong) -> Result<(), SslError> {
+        unsafe {
+            if ffi::BN_add_word(self.raw(), w) == 1 {
+                Ok(())
+            } else {
+                Err(SslError::get())
+            }
+        }
+    }
+
+    pub fn sub_word(&mut self, w: c_ulong) -> Result<(), SslError> {
+        unsafe {
+            if ffi::BN_sub_word(self.raw(), w) == 1 {
+                Ok(())
+            } else {
+                Err(SslError::get())
+            }
+        }
+    }
+
+    pub fn mul_word(&mut self, w: c_ulong) -> Result<(), SslError> {
+        unsafe {
+            if ffi::BN_mul_word(self.raw(), w) == 1 {
+                Ok(())
+            } else {
+                Err(SslError::get())
+            }
+        }
+    }
+
+    pub fn div_word(&mut self, w: c_ulong) -> Result<c_ulong, SslError> {
+        unsafe {
+            let result = ffi::BN_div_word(self.raw(), w);
+            if result != !0 as c_ulong {
+                Ok(result)
+            } else {
+                Err(SslError::get())
+            }
+        }
+    }
+
+    pub fn mod_word(&self, w: c_ulong) -> Result<c_ulong, SslError> {
+        unsafe {
+            let result = ffi::BN_mod_word(self.raw(), w);
+            if result != !0 as c_ulong {
+                Ok(result)
+            } else {
+                Err(SslError::get())
+            }
+        }
+    }
+
+    pub fn checked_gcd(&self, a: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_gcd(r.raw(), self.raw(), a.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_generate_prime(bits: i32, safe: bool, add: Option<&BigNum>, rem: Option<&BigNum>) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, {
+                let add_arg = add.map(|a| a.raw()).unwrap_or(ptr::null_mut());
+                let rem_arg = rem.map(|r| r.raw()).unwrap_or(ptr::null_mut());
+
+                ffi::BN_generate_prime_ex(r.raw(), bits as c_int, safe as c_int, add_arg, rem_arg, ptr::null()) == 1
+            })
+        }
+    }
+
+    pub fn is_prime(&self, checks: i32) -> Result<bool, SslError> {
+        unsafe {
+            with_ctx!(ctx, {
+                Ok(ffi::BN_is_prime_ex(self.raw(), checks as c_int, ctx, ptr::null()) == 1)
+            })
+        }
+    }
+
+    pub fn is_prime_fast(&self, checks: i32, do_trial_division: bool) -> Result<bool, SslError> {
+        unsafe {
+            with_ctx!(ctx, {
+                Ok(ffi::BN_is_prime_fasttest_ex(self.raw(), checks as c_int, ctx, do_trial_division as c_int, ptr::null()) == 1)
+            })
+        }
+    }
+
+    pub fn checked_new_random(bits: i32, prop: RNGProperty, odd: bool) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_rand(r.raw(), bits as c_int, prop as c_int, odd as c_int) == 1 })
+        }
+    }
+
+    pub fn checked_new_pseudo_random(bits: i32, prop: RNGProperty, odd: bool) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_pseudo_rand(r.raw(), bits as c_int, prop as c_int, odd as c_int) == 1 })
+        }
+    }
+
+    pub fn checked_rand_in_range(&self) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_rand_range(r.raw(), self.raw()) == 1 })
+        }
+    }
+
+    pub fn checked_pseudo_rand_in_range(&self) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_pseudo_rand_range(r.raw(), self.raw()) == 1 })
+        }
+    }
+
+    pub fn set_bit(&mut self, n: i32) -> Result<(), SslError> {
+        unsafe {
+            if ffi::BN_set_bit(self.raw(), n as c_int) == 1 {
+                Ok(())
+            } else {
+                Err(SslError::get())
+            }
+        }
+    }
+
+    pub fn clear_bit(&mut self, n: i32) -> Result<(), SslError> {
+        unsafe {
+            if ffi::BN_clear_bit(self.raw(), n as c_int) == 1 {
+                Ok(())
+            } else {
+                Err(SslError::get())
+            }
+        }
+    }
+
+    pub fn is_bit_set(&self, n: i32) -> bool {
+        unsafe {
+            ffi::BN_is_bit_set(self.raw(), n as c_int) == 1
+        }
+    }
+
+    pub fn mask_bits(&mut self, n: i32) -> Result<(), SslError> {
+        unsafe {
+            if ffi::BN_mask_bits(self.raw(), n as c_int) == 1 {
+                Ok(())
+            } else {
+                Err(SslError::get())
+            }
+        }
+    }
+
+    pub fn checked_shl1(&self) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn!(r, { ffi::BN_lshift1(r.raw(), self.raw()) == 1 })
+        }
+    }
+
+    pub fn checked_shr1(&self) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn!(r, { ffi::BN_rshift1(r.raw(), self.raw()) == 1 })
+        }
+    }
+
+    pub fn checked_add(&self, a: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn!(r, { ffi::BN_add(r.raw(), self.raw(), a.raw()) == 1 })
+        }
+    }
+
+    pub fn checked_sub(&self, a: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn!(r, { ffi::BN_sub(r.raw(), self.raw(), a.raw()) == 1 })
+        }
+    }
+
+    pub fn checked_mul(&self, a: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_mul(r.raw(), self.raw(), a.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_div(&self, a: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_div(r.raw(), ptr::null_mut(), self.raw(), a.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_mod(&self, a: &BigNum) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn_in_ctx!(r, ctx, { ffi::BN_div(ptr::null_mut(), r.raw(), self.raw(), a.raw(), ctx) == 1 })
+        }
+    }
+
+    pub fn checked_shl(&self, a: &i32) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn!(r, { ffi::BN_lshift(r.raw(), self.raw(), *a as c_int) == 1 })
+        }
+    }
+
+    pub fn checked_shr(&self, a: &i32) -> Result<BigNum, SslError> {
+        unsafe {
+            with_bn!(r, { ffi::BN_rshift(r.raw(), self.raw(), *a as c_int) == 1 })
+        }
+    }
+
+    pub fn negate(&mut self) {
+        unsafe {
+            ffi::BN_set_negative(self.raw(), !self.is_negative() as c_int)
+        }
+    }
+
+    pub fn abs_cmp(&self, oth: BigNum) -> Ordering {
+        unsafe {
+            let res = ffi::BN_ucmp(self.raw(), oth.raw()) as i32;
+            if res < 0 {
+                Ordering::Less
+            } else if res > 0 {
+                Ordering::Greater
+            } else {
+                Ordering::Equal
+            }
+        }
+    }
+
+    pub fn is_negative(&self) -> bool {
+        unsafe {
+            (*self.raw()).neg == 1
+        }
+    }
+
+    pub fn num_bits(&self) -> i32 {
+        unsafe {
+            ffi::BN_num_bits(self.raw()) as i32
+        }
+    }
+
+    pub fn num_bytes(&self) -> i32 {
+        (self.num_bits() + 7) / 8
+    }
+
+    unsafe fn raw(&self) -> *mut ffi::BIGNUM {
+        let BigNum(n) = *self;
+        n
+    }
+
+    unsafe fn raw_ptr(&self) -> *const *mut ffi::BIGNUM {
+        let BigNum(ref n) = *self;
+        n
+    }
+
+    pub fn to_vec(&self) -> Vec<u8> {
+        let size = self.num_bytes() as usize;
+        let mut v = Vec::with_capacity(size);
+        unsafe {
+            ffi::BN_bn2bin(self.raw(), v.as_mut_ptr());
+            v.set_len(size);
+        }
+        v
+    }
+
+    pub fn to_dec_str(&self) -> String {
+        unsafe {
+            let buf = ffi::BN_bn2dec(self.raw());
+            assert!(!buf.is_null());
+            let str = String::from_utf8(CStr::from_ptr(buf).to_bytes().to_vec()).unwrap();
+            ffi::CRYPTO_free(buf as *mut c_void);
+            str
+        }
+    }
+
+    pub fn to_hex_str(&self) -> String {
+        unsafe {
+            let buf = ffi::BN_bn2hex(self.raw());
+            assert!(!buf.is_null());
+            let str = String::from_utf8(CStr::from_ptr(buf).to_bytes().to_vec()).unwrap();
+            ffi::CRYPTO_free(buf as *mut c_void);
+            str
+        }
+    }
+}
+
+impl fmt::Debug for BigNum {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.to_dec_str())
+    }
+}
+
+impl Eq for BigNum { }
+impl PartialEq for BigNum {
+    fn eq(&self, oth: &BigNum) -> bool {
+        unsafe {
+            ffi::BN_cmp(self.raw(), oth.raw()) == 0
+        }
+    }
+}
+
+impl Ord for BigNum {
+    fn cmp(&self, oth: &BigNum) -> Ordering {
+        self.partial_cmp(oth).unwrap()
+    }
+}
+
+impl PartialOrd for BigNum {
+    fn partial_cmp(&self, oth: &BigNum) -> Option<Ordering> {
+        unsafe {
+            let v = ffi::BN_cmp(self.raw(), oth.raw());
+            let ret =
+                if v == 0 {
+                    Ordering::Equal
+                } else if v < 0 {
+                    Ordering::Less
+                } else {
+                    Ordering::Greater
+                };
+            Some(ret)
+        }
+    }
+}
+
+impl Drop for BigNum {
+    fn drop(&mut self) {
+        unsafe {
+            if !self.raw().is_null() {
+                ffi::BN_clear_free(self.raw());
+            }
+        }
+    }
+}
+
+pub mod unchecked {
+    use std::ops::{Add, Div, Mul, Neg, Rem, Shl, Shr, Sub};
+    use ffi;
+    use super::{BigNum};
+
+    impl<'a> Add<&'a BigNum> for &'a BigNum {
+        type Output = BigNum;
+
+        fn add(self, oth: &'a BigNum) -> BigNum {
+            self.checked_add(oth).unwrap()
+        }
+    }
+
+    impl<'a> Sub<&'a BigNum> for &'a BigNum {
+        type Output = BigNum;
+
+        fn sub(self, oth: &'a BigNum) -> BigNum {
+            self.checked_sub(oth).unwrap()
+        }
+    }
+
+    impl<'a> Mul<&'a BigNum> for &'a BigNum {
+        type Output = BigNum;
+
+        fn mul(self, oth: &'a BigNum) -> BigNum {
+            self.checked_mul(oth).unwrap()
+        }
+    }
+
+    impl<'a> Div<&'a BigNum> for &'a BigNum {
+        type Output = BigNum;
+
+        fn div(self, oth: &'a BigNum) -> BigNum {
+            self.checked_div(oth).unwrap()
+        }
+    }
+
+    impl<'a> Rem<&'a BigNum> for &'a BigNum {
+        type Output = BigNum;
+
+        fn rem(self, oth: &'a BigNum) -> BigNum {
+            self.checked_mod(oth).unwrap()
+        }
+    }
+
+    impl<'a> Shl<i32> for &'a BigNum {
+        type Output = BigNum;
+
+        fn shl(self, n: i32) -> BigNum {
+            self.checked_shl(&n).unwrap()
+        }
+    }
+
+    impl<'a> Shr<i32> for &'a BigNum {
+        type Output = BigNum;
+
+        fn shr(self, n: i32) -> BigNum {
+            self.checked_shr(&n).unwrap()
+        }
+    }
+
+    impl Clone for BigNum {
+        fn clone(&self) -> BigNum {
+            unsafe {
+                let r = ffi::BN_dup(self.raw());
+                if r.is_null() {
+                    panic!("Unexpected null pointer from BN_dup(..)")
+                } else {
+                    BigNum(r)
+                }
+            }
+        }
+    }
+
+    impl Neg for BigNum {
+        type Output = BigNum;
+
+        fn neg(self) -> BigNum {
+            let mut n = self.clone();
+            n.negate();
+            n
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use bn::BigNum;
+
+    #[test]
+    fn test_to_from_slice() {
+        let v0 = BigNum::new_from(10203004_u64).unwrap();
+        let vec = v0.to_vec();
+        let v1 = BigNum::new_from_slice(&vec).unwrap();
+
+        assert!(v0 == v1);
+    }
+
+    #[test]
+    fn test_negation() {
+        let a = BigNum::new_from(909829283_u64).unwrap();
+
+        assert!(!a.is_negative());
+        assert!((-a).is_negative());
+    }
+
+
+    #[test]
+    fn test_prime_numbers() {
+        let a = BigNum::new_from(19029017_u64).unwrap();
+        let p = BigNum::checked_generate_prime(128, true, None, Some(&a)).unwrap();
+
+        assert!(p.is_prime(100).unwrap());
+        assert!(p.is_prime_fast(100, true).unwrap());
+    }
+}
+

+

Keyboard shortcuts

Search tricks