bitcoin-core · gmaxwell · Sep 28, 2015 · Sep 29, 2015
diff --git a/configure.ac b/configure.ac
@@ -62,27 +62,6 @@ case $host_os in
    ;;
 esac
 
-CFLAGS="$CFLAGS -W"
-
-warn_CFLAGS="-std=c89 -pedantic -Wall -Wextra -Wcast-align -Wnested-externs -Wshadow -Wstrict-prototypes -Wno-unused-function -Wno-long-long -Wno-overlength-strings"
-saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS $warn_CFLAGS"
-AC_MSG_CHECKING([if ${CC} supports ${warn_CFLAGS}])
-AC_COMPILE_IFELSE([AC_LANG_SOURCE([[char foo;]])],
-    [ AC_MSG_RESULT([yes]) ],
-    [ AC_MSG_RESULT([no])
-      CFLAGS="$saved_CFLAGS"
-    ])
-
-saved_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -fvisibility=hidden"
-AC_MSG_CHECKING([if ${CC} supports -fvisibility=hidden])
-AC_COMPILE_IFELSE([AC_LANG_SOURCE([[char foo;]])],
-    [ AC_MSG_RESULT([yes]) ],
-    [ AC_MSG_RESULT([no])
-      CFLAGS="$saved_CFLAGS"
-    ])
-
 AC_ARG_ENABLE(benchmark,
     AS_HELP_STRING([--enable-benchmark],[compile benchmark (default is no)]),
     [use_benchmark=$enableval],
@@ -130,6 +109,42 @@ AC_ARG_WITH([scalar], [AS_HELP_STRING([--with-scalar=64bit|32bit|auto],
 AC_ARG_WITH([asm], [AS_HELP_STRING([--with-asm=x86_64|no|auto]
 [Specify assembly optimizations to use. Default is auto])],[req_asm=$withval], [req_asm=auto])
 
+CFLAGS="$CFLAGS -W"
+
+dnl There are a few intentionally unused functions if you are not building with all the bells and whistles.
+warn_unused_CFLAGS="-Wno-unused-function"
+dnl if all modules are enabled and no static precomp, don't add -Wno-unused-function
+if test x"$use_ecmult_static_precomputation" = x"no"; then
+ if test x"$enable_module_ecdh" = x"yes"; then
+  if test x"$enable_module_schnorr" = x"yes"; then
+   if test x"$enable_module_recovery" = x"yes"; then
+    warn_unused_CFLAGS=""
+   fi
+  fi
+ fi
+fi
+
+dnl -Wno-overlength-strings is needed by some versions of clang due to spurious warnings on assembly code.
+warn_CFLAGS="-std=c89 -pedantic -Wall -Wextra -Wcast-align -Wnested-externs -Wshadow -Wstrict-prototypes -Wno-long-long -Wno-overlength-strings $warn_unused_CFLAGS"
+
+saved_CFLAGS="$CFLAGS"
+CFLAGS="$CFLAGS $warn_CFLAGS"
+AC_MSG_CHECKING([if ${CC} supports ${warn_CFLAGS}])
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([[char foo;]])],
+    [ AC_MSG_RESULT([yes]) ],
+    [ AC_MSG_RESULT([no])
+      CFLAGS="$saved_CFLAGS"
+    ])
+
+saved_CFLAGS="$CFLAGS"
+CFLAGS="$CFLAGS -fvisibility=hidden"
+AC_MSG_CHECKING([if ${CC} supports -fvisibility=hidden])
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([[char foo;]])],
+    [ AC_MSG_RESULT([yes]) ],
+    [ AC_MSG_RESULT([no])
+      CFLAGS="$saved_CFLAGS"
+    ])
+
 AC_CHECK_TYPES([__int128])
 
 AC_MSG_CHECKING([for __builtin_expect])

diff --git a/src/ecdsa.h b/src/ecdsa.h
@@ -17,6 +17,5 @@ static int secp256k1_ecdsa_sig_parse(secp256k1_scalar *r, secp256k1_scalar *s, c
 static int secp256k1_ecdsa_sig_serialize(unsigned char *sig, size_t *size, const secp256k1_scalar *r, const secp256k1_scalar *s);
 static int secp256k1_ecdsa_sig_verify(const secp256k1_ecmult_context *ctx, const secp256k1_scalar* r, const secp256k1_scalar* s, const secp256k1_ge *pubkey, const secp256k1_scalar *message);
 static int secp256k1_ecdsa_sig_sign(const secp256k1_ecmult_gen_context *ctx, secp256k1_scalar* r, secp256k1_scalar* s, const secp256k1_scalar *seckey, const secp256k1_scalar *message, const secp256k1_scalar *nonce, int *recid);
-static int secp256k1_ecdsa_sig_recover(const secp256k1_ecmult_context *ctx, const secp256k1_scalar* r, const secp256k1_scalar* s, secp256k1_ge *pubkey, const secp256k1_scalar *message, int recid);
 
 #endif
diff --git a/src/ecdsa_impl.h b/src/ecdsa_impl.h
@@ -187,39 +187,6 @@ static int secp256k1_ecdsa_sig_verify(const secp256k1_ecmult_context *ctx, const
     return 0;
 }
 
-static int secp256k1_ecdsa_sig_recover(const secp256k1_ecmult_context *ctx, const secp256k1_scalar *sigr, const secp256k1_scalar* sigs, secp256k1_ge *pubkey, const secp256k1_scalar *message, int recid) {
-    unsigned char brx[32];
-    secp256k1_fe fx;
-    secp256k1_ge x;
-    secp256k1_gej xj;
-    secp256k1_scalar rn, u1, u2;
-    secp256k1_gej qj;
-
-    if (secp256k1_scalar_is_zero(sigr) || secp256k1_scalar_is_zero(sigs)) {
-        return 0;
-    }
-
-    secp256k1_scalar_get_b32(brx, sigr);
-    VERIFY_CHECK(secp256k1_fe_set_b32(&fx, brx)); /* brx comes from a scalar, so is less than the order; certainly less than p */
-    if (recid & 2) {
-        if (secp256k1_fe_cmp_var(&fx, &secp256k1_ecdsa_const_p_minus_order) >= 0) {
-            return 0;
-        }
-        secp256k1_fe_add(&fx, &secp256k1_ecdsa_const_order_as_fe);
-    }
-    if (!secp256k1_ge_set_xo_var(&x, &fx, recid & 1)) {
-        return 0;
-    }
-    secp256k1_gej_set_ge(&xj, &x);
-    secp256k1_scalar_inverse_var(&rn, sigr);
-    secp256k1_scalar_mul(&u1, &rn, message);
-    secp256k1_scalar_negate(&u1, &u1);
-    secp256k1_scalar_mul(&u2, &rn, sigs);
-    secp256k1_ecmult(ctx, &qj, &xj, &u2, &u1);
-    secp256k1_ge_set_gej_var(pubkey, &qj);
-    return !secp256k1_gej_is_infinity(&qj);
-}
-
 static int secp256k1_ecdsa_sig_sign(const secp256k1_ecmult_gen_context *ctx, secp256k1_scalar *sigr, secp256k1_scalar *sigs, const secp256k1_scalar *seckey, const secp256k1_scalar *message, const secp256k1_scalar *nonce, int *recid) {
     unsigned char b[32];
     secp256k1_gej rp;

diff --git a/src/field_10x26_impl.h b/src/field_10x26_impl.h
@@ -40,10 +40,6 @@ static void secp256k1_fe_verify(const secp256k1_fe *a) {
     }
     VERIFY_CHECK(r == 1);
 }
-#else
-static void secp256k1_fe_verify(const secp256k1_fe *a) {
-    (void)a;
-}
 #endif
 
 static void secp256k1_fe_normalize(secp256k1_fe *r) {

diff --git a/src/field_5x52_impl.h b/src/field_5x52_impl.h
@@ -50,10 +50,6 @@ static void secp256k1_fe_verify(const secp256k1_fe *a) {
     }
     VERIFY_CHECK(r == 1);
 }
-#else
-static void secp256k1_fe_verify(const secp256k1_fe *a) {
-    (void)a;
-}
 #endif
 
 static void secp256k1_fe_normalize(secp256k1_fe *r) {

diff --git a/src/group.h b/src/group.h
@@ -58,6 +58,9 @@ static void secp256k1_ge_neg(secp256k1_ge *r, const secp256k1_ge *a);
 /** Set a group element equal to another which is given in jacobian coordinates */
 static void secp256k1_ge_set_gej(secp256k1_ge *r, secp256k1_gej *a);
 
+/** Set a group element equal to another which is given in jacobian coordinates */
+static void secp256k1_ge_set_gej_var(secp256k1_ge *r, secp256k1_gej *a);
+
 /** Set a batch of group elements equal to the inputs given in jacobian coordinates */
 static void secp256k1_ge_set_all_gej_var(size_t len, secp256k1_ge *r, const secp256k1_gej *a, const secp256k1_callback *cb);
 

diff --git a/src/group_impl.h b/src/group_impl.h
@@ -211,26 +211,6 @@ static int secp256k1_gej_is_infinity(const secp256k1_gej *a) {
     return a->infinity;
 }
 
-static int secp256k1_gej_is_valid_var(const secp256k1_gej *a) {
-    secp256k1_fe y2, x3, z2, z6;
-    if (a->infinity) {
-        return 0;
-    }
-    /** y^2 = x^3 + 7
-     *  (Y/Z^3)^2 = (X/Z^2)^3 + 7
-     *  Y^2 / Z^6 = X^3 / Z^6 + 7
-     *  Y^2 = X^3 + 7*Z^6
-     */
-    secp256k1_fe_sqr(&y2, &a->y);
-    secp256k1_fe_sqr(&x3, &a->x); secp256k1_fe_mul(&x3, &x3, &a->x);
-    secp256k1_fe_sqr(&z2, &a->z);
-    secp256k1_fe_sqr(&z6, &z2); secp256k1_fe_mul(&z6, &z6, &z2);
-    secp256k1_fe_mul_int(&z6, 7);
-    secp256k1_fe_add(&x3, &z6);
-    secp256k1_fe_normalize_weak(&x3);
-    return secp256k1_fe_equal_var(&y2, &x3);
-}
-
 static int secp256k1_ge_is_valid_var(const secp256k1_ge *a) {
     secp256k1_fe y2, x3, c;
     if (a->infinity) {

diff --git a/src/modules/recovery/main_impl.h b/src/modules/recovery/main_impl.h
@@ -130,6 +130,39 @@ int secp256k1_ecdsa_sign_recoverable(const secp256k1_context* ctx, secp256k1_ecd
     return ret;
 }
 
+static int secp256k1_ecdsa_sig_recover(const secp256k1_ecmult_context *ctx, const secp256k1_scalar *sigr, const secp256k1_scalar* sigs, secp256k1_ge *pubkey, const secp256k1_scalar *message, int recid) {
+    unsigned char brx[32];
+    secp256k1_fe fx;
+    secp256k1_ge x;
+    secp256k1_gej xj;
+    secp256k1_scalar rn, u1, u2;
+    secp256k1_gej qj;
+
+    if (secp256k1_scalar_is_zero(sigr) || secp256k1_scalar_is_zero(sigs)) {
+        return 0;
+    }
+
+    secp256k1_scalar_get_b32(brx, sigr);
+    VERIFY_CHECK(secp256k1_fe_set_b32(&fx, brx)); /* brx comes from a scalar, so is less than the order; certainly less than p */
+    if (recid & 2) {
+        if (secp256k1_fe_cmp_var(&fx, &secp256k1_ecdsa_const_p_minus_order) >= 0) {
+            return 0;
+        }
+        secp256k1_fe_add(&fx, &secp256k1_ecdsa_const_order_as_fe);
+    }
+    if (!secp256k1_ge_set_xo_var(&x, &fx, recid & 1)) {
+        return 0;
+    }
+    secp256k1_gej_set_ge(&xj, &x);
+    secp256k1_scalar_inverse_var(&rn, sigr);
+    secp256k1_scalar_mul(&u1, &rn, message);
+    secp256k1_scalar_negate(&u1, &u1);
+    secp256k1_scalar_mul(&u2, &rn, sigs);
+    secp256k1_ecmult(ctx, &qj, &xj, &u2, &u1);
+    secp256k1_ge_set_gej_var(pubkey, &qj);
+    return !secp256k1_gej_is_infinity(&qj);
+}
+
 int secp256k1_ecdsa_recover(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const secp256k1_ecdsa_recoverable_signature *signature, const unsigned char *msg32) {
     secp256k1_ge q;
     secp256k1_scalar r, s;

diff --git a/src/num.h b/src/num.h
@@ -19,8 +19,6 @@
 #error "Please select num implementation"
 #endif
 
-/** Copy a number. */
-static void secp256k1_num_copy(secp256k1_num *r, const secp256k1_num *a);
 
 /** Convert a number's absolute value to a binary big-endian string.
  *  There must be enough place. */
@@ -32,37 +30,6 @@ static void secp256k1_num_set_bin(secp256k1_num *r, const unsigned char *a, unsi
 /** Compute a modular inverse. The input must be less than the modulus. */
 static void secp256k1_num_mod_inverse(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *m);
 
-/** Compare the absolute value of two numbers. */
-static int secp256k1_num_cmp(const secp256k1_num *a, const secp256k1_num *b);
-
-/** Test whether two number are equal (including sign). */
-static int secp256k1_num_eq(const secp256k1_num *a, const secp256k1_num *b);
-
-/** Add two (signed) numbers. */
-static void secp256k1_num_add(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b);
-
-/** Subtract two (signed) numbers. */
-static void secp256k1_num_sub(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b);
-
-/** Multiply two (signed) numbers. */
-static void secp256k1_num_mul(secp256k1_num *r, const secp256k1_num *a, const secp256k1_num *b);
-
-/** Replace a number by its remainder modulo m. M's sign is ignored. The result is a number between 0 and m-1,
-    even if r was negative. */
-static void secp256k1_num_mod(secp256k1_num *r, const secp256k1_num *m);
-
-/** Right-shift the passed number by bits bits. */
-static void secp256k1_num_shift(secp256k1_num *r, int bits);
-
-/** Check whether a number is zero. */
-static int secp256k1_num_is_zero(const secp256k1_num *a);
-
-/** Check whether a number is strictly negative. */
-static int secp256k1_num_is_neg(const secp256k1_num *a);
-
-/** Change a number's sign. */
-static void secp256k1_num_negate(secp256k1_num *r);
-
 #endif
 
 #endif