Add some more useful bigint functions to C interface

2 files changed, 137 insertions, 47 deletions

diff --git a/src/lib/ffi/ffi.cpp b/src/lib/ffi/ffi.cpp
index 8eb984c55..37664daa3 100644
--- a/src/lib/ffi/ffi.cpp
+++ b/src/lib/ffi/ffi.cpp
@@ -330,6 +330,11 @@ int botan_mp_init(botan_mp_t* mp)
    return 0;
    }
 
+int botan_mp_clear(botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.clear(); });
+   }
+
 int botan_mp_set_from_int(botan_mp_t mp, int initial_value)
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
@@ -350,16 +355,39 @@ int botan_mp_set_from_str(botan_mp_t mp, const char* str)
    return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn = Botan::BigInt(str); });
    }
 
-int botan_mp_set_from_mp(botan_mp_t dest, botan_mp_t source)
+int botan_mp_set_from_radix_str(botan_mp_t mp, const char* str, size_t radix)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
+      Botan::BigInt::Base base;
+      if(radix == 10)
+         base = Botan::BigInt::Decimal;
+      else if(radix == 16)
+         base = Botan::BigInt::Hexadecimal;
+      else
+         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+
+      const uint8_t* bytes = reinterpret_cast<const uint8_t*>(str);
+      const size_t len = strlen(str);
+
+      bn = Botan::BigInt::decode(bytes, len, base);
+      });
+   }
+
+int botan_mp_set_from_mp(botan_mp_t dest, const botan_mp_t source)
    {
    return BOTAN_FFI_DO(Botan::BigInt, dest, bn, { bn = safe_get(source); });
    }
 
-int botan_mp_is_negative(botan_mp_t mp)
+int botan_mp_is_negative(const botan_mp_t mp)
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_negative() ? 1 : 0; });
    }
 
+int botan_mp_is_positive(const botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_positive() ? 1 : 0; });
+   }
+
 int botan_mp_flip_sign(botan_mp_t mp)
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.flip_sign(); });
@@ -370,7 +398,7 @@ int botan_mp_from_bin(botan_mp_t mp, const uint8_t bin[], size_t bin_len)
    return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.binary_decode(bin, bin_len); });
    }
 
-int botan_mp_to_hex(botan_mp_t mp, char* out)
+int botan_mp_to_hex(const botan_mp_t mp, char* out)
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
       std::vector<uint8_t> hex = Botan::BigInt::encode(bn, Botan::BigInt::Hexadecimal);
@@ -379,7 +407,7 @@ int botan_mp_to_hex(botan_mp_t mp, char* out)
       });
    }
 
-int botan_mp_to_str(botan_mp_t mp, uint8_t digit_base, char* out, size_t* out_len)
+int botan_mp_to_str(const botan_mp_t mp, uint8_t digit_base, char* out, size_t* out_len)
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
       Botan::BigInt::Base base;
@@ -396,35 +424,43 @@ int botan_mp_to_str(botan_mp_t mp, uint8_t digit_base, char* out, size_t* out_le
       });
    }
 
-int botan_mp_to_bin(botan_mp_t mp, uint8_t vec[])
+int botan_mp_to_bin(const botan_mp_t mp, uint8_t vec[])
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.binary_encode(vec); });
    }
 
+int botan_mp_to_uint32(const botan_mp_t mp, uint32_t* val)
+   {
+   if(val == nullptr) {
+   return BOTAN_FFI_ERROR_NULL_POINTER;
+   }
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { *val = bn.to_u32bit(); });
+   }
+
 int botan_mp_destroy(botan_mp_t mp)
    {
    delete mp;
    return 0;
    }
 
-int botan_mp_add(botan_mp_t result, botan_mp_t x, botan_mp_t y)
+int botan_mp_add(botan_mp_t result, const botan_mp_t x, const botan_mp_t y)
    {
    return BOTAN_FFI_DO(Botan::BigInt, result, res, { res = safe_get(x) + safe_get(y); });
    }
 
-int botan_mp_sub(botan_mp_t result, botan_mp_t x, botan_mp_t y)
+int botan_mp_sub(botan_mp_t result, const botan_mp_t x, const botan_mp_t y)
    {
    return BOTAN_FFI_DO(Botan::BigInt, result, res, { res = safe_get(x) - safe_get(y); });
    }
 
-int botan_mp_mul(botan_mp_t result, botan_mp_t x, botan_mp_t y)
+int botan_mp_mul(botan_mp_t result, const botan_mp_t x, const botan_mp_t y)
    {
    return BOTAN_FFI_DO(Botan::BigInt, result, res, { res = safe_get(x) * safe_get(y); });
    }
 
 int botan_mp_div(botan_mp_t quotient,
                  botan_mp_t remainder,
-                 botan_mp_t x, botan_mp_t y)
+                 const botan_mp_t x, const botan_mp_t y)
    {
    return BOTAN_FFI_DO(Botan::BigInt, quotient, q, {
       Botan::BigInt r;
@@ -433,12 +469,27 @@ int botan_mp_div(botan_mp_t quotient,
       });
    }
 
-int botan_mp_equal(botan_mp_t x_w, botan_mp_t y_w)
+int botan_mp_equal(const botan_mp_t x_w, const botan_mp_t y_w)
    {
    return BOTAN_FFI_DO(Botan::BigInt, x_w, x, { return x == safe_get(y_w); });
    }
 
-int botan_mp_cmp(int* result, botan_mp_t x_w, botan_mp_t y_w)
+int botan_mp_is_zero(const botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_zero(); });
+   }
+
+int botan_mp_is_odd(const botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_odd(); });
+   }
+
+int botan_mp_is_even(const botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_even(); });
+   }
+
+int botan_mp_cmp(int* result, const botan_mp_t x_w, const botan_mp_t y_w)
    {
    return BOTAN_FFI_DO(Botan::BigInt, x_w, x, { *result = x.cmp(safe_get(y_w)); });
    }
@@ -449,28 +500,28 @@ int botan_mp_swap(botan_mp_t x_w, botan_mp_t y_w)
    }
 
 // Return (base^exponent) % modulus
-int botan_mp_powmod(botan_mp_t out, botan_mp_t base, botan_mp_t exponent, botan_mp_t modulus)
+int botan_mp_powmod(botan_mp_t out, const botan_mp_t base, const botan_mp_t exponent, const botan_mp_t modulus)
    {
    return BOTAN_FFI_DO(Botan::BigInt, out, o,
                        { o = Botan::power_mod(safe_get(base), safe_get(exponent), safe_get(modulus)); });
    }
 
-int botan_mp_lshift(botan_mp_t out, botan_mp_t in, size_t shift)
+int botan_mp_lshift(botan_mp_t out, const botan_mp_t in, size_t shift)
    {
    return BOTAN_FFI_DO(Botan::BigInt, out, o, { o = safe_get(in) << shift; });
    }
 
-int botan_mp_rshift(botan_mp_t out, botan_mp_t in, size_t shift)
+int botan_mp_rshift(botan_mp_t out, const botan_mp_t in, size_t shift)
    {
    return BOTAN_FFI_DO(Botan::BigInt, out, o, { o = safe_get(in) >> shift; });
    }
 
-int botan_mp_mod_inverse(botan_mp_t out, botan_mp_t in, botan_mp_t modulus)
+int botan_mp_mod_inverse(botan_mp_t out, const botan_mp_t in, const botan_mp_t modulus)
    {
    return BOTAN_FFI_DO(Botan::BigInt, out, o, { o = Botan::inverse_mod(safe_get(in), safe_get(modulus)); });
    }
 
-int botan_mp_mod_mul(botan_mp_t out, botan_mp_t x, botan_mp_t y, botan_mp_t modulus)
+int botan_mp_mod_mul(botan_mp_t out, const botan_mp_t x, const botan_mp_t y, const botan_mp_t modulus)
    {
    return BOTAN_FFI_DO(Botan::BigInt, out, o, {
       Botan::Modular_Reducer reducer(safe_get(modulus));
@@ -486,41 +537,50 @@ int botan_mp_rand_bits(botan_mp_t rand_out, botan_rng_t rng, size_t bits)
 
 int botan_mp_rand_range(botan_mp_t rand_out,
                         botan_rng_t rng,
-                        botan_mp_t lower,
-                        botan_mp_t upper)
+                        const botan_mp_t lower,
+                        const botan_mp_t upper)
    {
    return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, {
       safe_get(rand_out) = Botan::BigInt::random_integer(r, safe_get(lower), safe_get(upper)); });
    }
 
-int botan_mp_gcd(botan_mp_t out, botan_mp_t x, botan_mp_t y)
+int botan_mp_gcd(botan_mp_t out, const botan_mp_t x, const botan_mp_t y)
    {
    return BOTAN_FFI_DO(Botan::BigInt, out, o, {
       o = Botan::gcd(safe_get(x), safe_get(y)); });
    }
 
-int botan_mp_is_prime(botan_mp_t mp, botan_rng_t rng, size_t test_prob)
+int botan_mp_is_prime(const botan_mp_t mp, botan_rng_t rng, size_t test_prob)
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, n,
                        { return (Botan::is_prime(n, safe_get(rng), test_prob)) ? 1 : 0; });
    }
 
-int botan_mp_bit_set(botan_mp_t mp, size_t bit)
+int botan_mp_get_bit(const botan_mp_t mp, size_t bit)
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, n, { return (n.get_bit(bit)); });
    }
 
-int botan_mp_num_bits(botan_mp_t mp, size_t* bits)
+int botan_mp_set_bit(botan_mp_t mp, size_t bit)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { n.set_bit(bit); });
+   }
+
+int botan_mp_clear_bit(botan_mp_t mp, size_t bit)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { n.clear_bit(bit); });
+   }
+
+int botan_mp_num_bits(const botan_mp_t mp, size_t* bits)
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, n, { *bits = n.bits(); });
    }
 
-int botan_mp_num_bytes(botan_mp_t mp, size_t* bytes)
+int botan_mp_num_bytes(const botan_mp_t mp, size_t* bytes)
    {
    return BOTAN_FFI_DO(Botan::BigInt, mp, n, { *bytes = n.bytes(); });
    }
 
-
 int botan_hash_init(botan_hash_t* hash, const char* hash_name, uint32_t flags)
    {
    try
diff --git a/src/lib/ffi/ffi.h b/src/lib/ffi/ffi.h
index 661368c18..3d62bb8c0 100644
--- a/src/lib/ffi/ffi.h
+++ b/src/lib/ffi/ffi.h
@@ -464,46 +464,66 @@ BOTAN_DLL int botan_mp_init(botan_mp_t* mp);
 BOTAN_DLL int botan_mp_destroy(botan_mp_t mp);
 
 // writes botan_mp_num_bytes(mp)*2 + 1 bytes to out[]
-BOTAN_DLL int botan_mp_to_hex(botan_mp_t mp, char* out);
-BOTAN_DLL int botan_mp_to_str(botan_mp_t mp, uint8_t base, char* out, size_t* out_len);
+BOTAN_DLL int botan_mp_to_hex(const botan_mp_t mp, char* out);
+BOTAN_DLL int botan_mp_to_str(const botan_mp_t mp, uint8_t base, char* out, size_t* out_len);
+
+BOTAN_DLL int botan_mp_clear(botan_mp_t mp);
 
 BOTAN_DLL int botan_mp_set_from_int(botan_mp_t mp, int initial_value);
-BOTAN_DLL int botan_mp_set_from_mp(botan_mp_t dest, botan_mp_t source);
+BOTAN_DLL int botan_mp_set_from_mp(botan_mp_t dest, const botan_mp_t source);
 BOTAN_DLL int botan_mp_set_from_str(botan_mp_t dest, const char* str);
+BOTAN_DLL int botan_mp_set_from_radix_str(botan_mp_t dest, const char* str, size_t radix);
 
-BOTAN_DLL int botan_mp_num_bits(botan_mp_t n, size_t* bits);
-BOTAN_DLL int botan_mp_num_bytes(botan_mp_t n, size_t* bytes);
+BOTAN_DLL int botan_mp_num_bits(const botan_mp_t n, size_t* bits);
+BOTAN_DLL int botan_mp_num_bytes(const botan_mp_t n, size_t* bytes);
 
 // Writes botan_mp_num_bytes(mp) to vec
-BOTAN_DLL int botan_mp_to_bin(botan_mp_t mp, uint8_t vec[]);
-BOTAN_DLL int botan_mp_from_bin(botan_mp_t mp, const uint8_t vec[], size_t vec_len);
+BOTAN_DLL int botan_mp_to_bin(const botan_mp_t mp, uint8_t vec[]);
+BOTAN_DLL int botan_mp_from_bin(const botan_mp_t mp, const uint8_t vec[], size_t vec_len);
+
+BOTAN_DLL int botan_mp_to_uint32(const botan_mp_t mp, uint32_t* val);
+
+/**
+* Return true iff mp is greater than 0
+*/
+BOTAN_DLL int botan_mp_is_positive(const botan_mp_t mp);
+
+/**
+* Return true iff mp is less than 0
+*/
+BOTAN_DLL int botan_mp_is_negative(const botan_mp_t mp);
 
-BOTAN_DLL int botan_mp_is_negative(botan_mp_t mp);
 BOTAN_DLL int botan_mp_flip_sign(botan_mp_t mp);
+//BOTAN_DLL int botan_mp_set_negative(botan_mp_t mp);
 
-BOTAN_DLL int botan_mp_add(botan_mp_t result, botan_mp_t x, botan_mp_t y);
-BOTAN_DLL int botan_mp_sub(botan_mp_t result, botan_mp_t x, botan_mp_t y);
-BOTAN_DLL int botan_mp_mul(botan_mp_t result, botan_mp_t x, botan_mp_t y);
+BOTAN_DLL int botan_mp_is_zero(const botan_mp_t mp);
+BOTAN_DLL int botan_mp_is_odd(const botan_mp_t mp);
+BOTAN_DLL int botan_mp_is_even(const botan_mp_t mp);
+
+BOTAN_DLL int botan_mp_add(botan_mp_t result, const botan_mp_t x, const botan_mp_t y);
+BOTAN_DLL int botan_mp_sub(botan_mp_t result, const botan_mp_t x, const botan_mp_t y);
+BOTAN_DLL int botan_mp_mul(botan_mp_t result, const botan_mp_t x, const botan_mp_t y);
 
 BOTAN_DLL int botan_mp_div(botan_mp_t quotient,
                            botan_mp_t remainder,
-                           botan_mp_t x, botan_mp_t y);
+                           const botan_mp_t x, const botan_mp_t y);
 
-BOTAN_DLL int botan_mp_mod_mul(botan_mp_t result, botan_mp_t x, botan_mp_t y, botan_mp_t mod);
+BOTAN_DLL int botan_mp_mod_mul(botan_mp_t result, const botan_mp_t x,
+                               const botan_mp_t y, const botan_mp_t mod);
 
 /*
 * Returns 0 if x != y
 * Returns 1 if x == y
 * Returns negative number on error
 */
-BOTAN_DLL int botan_mp_equal(botan_mp_t x, botan_mp_t y);
+BOTAN_DLL int botan_mp_equal(const botan_mp_t x, const botan_mp_t y);
 
 /*
 * Sets *result to comparison result:
 * -1 if x < y, 0 if x == y, 1 if x > y
 * Returns negative number on error or zero on success
 */
-BOTAN_DLL int botan_mp_cmp(int* result, botan_mp_t x, botan_mp_t y);
+BOTAN_DLL int botan_mp_cmp(int* result, const botan_mp_t x, const botan_mp_t y);
 
 /*
 * Swap two botan_mp_t
@@ -511,33 +531,43 @@ BOTAN_DLL int botan_mp_cmp(int* result, botan_mp_t x, botan_mp_t y);
 BOTAN_DLL int botan_mp_swap(botan_mp_t x, botan_mp_t y);
 
 // Return (base^exponent) % modulus
-BOTAN_DLL int botan_mp_powmod(botan_mp_t out, botan_mp_t base, botan_mp_t exponent, botan_mp_t modulus);
+BOTAN_DLL int botan_mp_powmod(botan_mp_t out, const botan_mp_t base, const botan_mp_t exponent, const botan_mp_t modulus);
 
-BOTAN_DLL int botan_mp_lshift(botan_mp_t out, botan_mp_t in, size_t shift);
-BOTAN_DLL int botan_mp_rshift(botan_mp_t out, botan_mp_t in, size_t shift);
+BOTAN_DLL int botan_mp_lshift(botan_mp_t out, const botan_mp_t in, size_t shift);
+BOTAN_DLL int botan_mp_rshift(botan_mp_t out, const botan_mp_t in, size_t shift);
 
-BOTAN_DLL int botan_mp_mod_inverse(botan_mp_t out, botan_mp_t in, botan_mp_t modulus);
+BOTAN_DLL int botan_mp_mod_inverse(botan_mp_t out, const botan_mp_t in, const botan_mp_t modulus);
 
 BOTAN_DLL int botan_mp_rand_bits(botan_mp_t rand_out, botan_rng_t rng, size_t bits);
 
 BOTAN_DLL int botan_mp_rand_range(botan_mp_t rand_out, botan_rng_t rng,
-                                  botan_mp_t lower_bound, botan_mp_t upper_bound);
+                                  const botan_mp_t lower_bound, const botan_mp_t upper_bound);
 
-BOTAN_DLL int botan_mp_gcd(botan_mp_t out, botan_mp_t x, botan_mp_t y);
+BOTAN_DLL int botan_mp_gcd(botan_mp_t out, const botan_mp_t x, const botan_mp_t y);
 
 /**
 * Returns 0 if n is not prime
 * Returns 1 if n is prime
 * Returns negative number on error
 */
-BOTAN_DLL int botan_mp_is_prime(botan_mp_t n, botan_rng_t rng, size_t test_prob);
+BOTAN_DLL int botan_mp_is_prime(const botan_mp_t n, botan_rng_t rng, size_t test_prob);
 
 /**
 * Returns 0 if specified bit of n is not set
 * Returns 1 if specified bit of n is set
 * Returns negative number on error
 */
-BOTAN_DLL int botan_mp_bit_set(botan_mp_t n, size_t bit);
+BOTAN_DLL int botan_mp_get_bit(const botan_mp_t n, size_t bit);
+
+/**
+* Set the specified bit
+*/
+BOTAN_DLL int botan_mp_set_bit(botan_mp_t n, size_t bit);
+
+/**
+* Clear the specified bit
+*/
+BOTAN_DLL int botan_mp_clear_bit(botan_mp_t n, size_t bit);
 
 /* Bcrypt password hashing */