diff --git a/src/libsodium/crypto_core/curve25519/ref10/curve25519_ref10.c b/src/libsodium/crypto_core/curve25519/ref10/curve25519_ref10.c
index 3552b63f..43c34969 100644
--- a/src/libsodium/crypto_core/curve25519/ref10/curve25519_ref10.c
+++ b/src/libsodium/crypto_core/curve25519/ref10/curve25519_ref10.c
@@ -3,7 +3,9 @@
 #include <string.h>
 
 #include "crypto_verify_32.h"
+#include "private/common.h"
 #include "private/curve25519_ref10.h"
+#include "utils.h"
 
 static inline uint64_t
 load_3(const unsigned char *in)
@@ -441,21 +443,19 @@ fe_isnegative(const fe f)
 /*
  return 1 if f == 0
  return 0 if f != 0
- *
+
  Preconditions:
  |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
  */
 
-static unsigned char zero[32];
-
 int
-fe_isnonzero(const fe f)
+fe_iszero(const fe f)
 {
     unsigned char s[32];
 
     fe_tobytes(s, f);
 
-    return crypto_verify_32(s, zero);
+    return sodium_is_zero(s, 32);
 }
 
 /*
@@ -1433,9 +1433,9 @@ ge_frombytes_negate_vartime(ge_p3 *h, const unsigned char *s)
     fe_sq(vxx, h->X);
     fe_mul(vxx, vxx, v);
     fe_sub(check, vxx, u); /* vx^2-u */
-    if (fe_isnonzero(check)) {
+    if (fe_iszero(check) == 0) {
         fe_add(check, vxx, u); /* vx^2+u */
-        if (fe_isnonzero(check)) {
+        if (fe_iszero(check) == 0) {
             return -1;
         }
         fe_mul(h->X, h->X, sqrtm1);
@@ -2037,7 +2037,7 @@ ge_scalarmult_base(ge_p3 *h, const unsigned char *a)
 }
 
 /* multiply by the order of the main subgroup l = 2^252+27742317777372353535851937790883648493 */
-void
+static void
 ge_mul_l(ge_p3 *r, const ge_p3 *A)
 {
     static const signed char aslide[253] = {
@@ -2091,6 +2091,91 @@ ge_mul_l(ge_p3 *r, const ge_p3 *A)
     }
 }
 
+int
+ge_is_on_main_subgroup(const ge_p3 *p)
+{
+    ge_p3 pl;
+
+    ge_mul_l(&pl, p);
+
+    return fe_iszero(pl.X);
+}
+
+int
+ge_has_small_order(const unsigned char s[32], unsigned char neg)
+{
+    CRYPTO_ALIGN(16)
+    static const unsigned char blacklist[][32] = {
+        /* 0 (order 4) */
+        { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
+        /* 1 (order 1) */
+        { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
+        /* 2707385501144840649318225287225658788936804267575313519463743609750303402022
+           (order 8) */
+        { 0x26, 0xe8, 0x95, 0x8f, 0xc2, 0xb2, 0x27, 0xb0, 0x45, 0xc3, 0xf4,
+          0x89, 0xf2, 0xef, 0x98, 0xf0, 0xd5, 0xdf, 0xac, 0x05, 0xd3, 0xc6,
+          0x33, 0x39, 0xb1, 0x38, 0x02, 0x88, 0x6d, 0x53, 0xfc, 0x05 },
+        /* 55188659117513257062467267217118295137698188065244968500265048394206261417927
+           (order 8) */
+        { 0xc7, 0x17, 0x6a, 0x70, 0x3d, 0x4d, 0xd8, 0x4f, 0xba, 0x3c, 0x0b,
+          0x76, 0x0d, 0x10, 0x67, 0x0f, 0x2a, 0x20, 0x53, 0xfa, 0x2c, 0x39,
+          0xcc, 0xc6, 0x4e, 0xc7, 0xfd, 0x77, 0x92, 0xac, 0x03, 0x7a },
+        /* p-1 (order 2) */
+        { 0x13, 0xe8, 0x95, 0x8f, 0xc2, 0xb2, 0x27, 0xb0, 0x45, 0xc3, 0xf4,
+          0x89, 0xf2, 0xef, 0x98, 0xf0, 0xd5, 0xdf, 0xac, 0x05, 0xd3, 0xc6,
+          0x33, 0x39, 0xb1, 0x38, 0x02, 0x88, 0x6d, 0x53, 0xfc, 0x85 },
+        /* p (order 4) */
+        { 0xb4, 0x17, 0x6a, 0x70, 0x3d, 0x4d, 0xd8, 0x4f, 0xba, 0x3c, 0x0b,
+          0x76, 0x0d, 0x10, 0x67, 0x0f, 0x2a, 0x20, 0x53, 0xfa, 0x2c, 0x39,
+          0xcc, 0xc6, 0x4e, 0xc7, 0xfd, 0x77, 0x92, 0xac, 0x03, 0xfa },
+        /* p+1 (order 1) */
+        { 0xec, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
+        /* p+2707385501144840649318225287225658788936804267575313519463743609750303402022
+           (order 8) */
+        { 0xed, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
+        /* p+55188659117513257062467267217118295137698188065244968500265048394206261417927
+           (order 8) */
+        { 0xee, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
+        /* 2p-1 (order 2) */
+        { 0xd9, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
+        /* 2p (order 4) */
+        { 0xda, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
+        /* 2p+1 (order 1) */
+        { 0xdb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }
+    };
+    size_t        i, j;
+    unsigned char c;
+
+    neg <<= 7;
+    for (i = 0; i < sizeof blacklist / sizeof blacklist[0]; i++) {
+        c = 0;
+        for (j = 0; j < 31; j++) {
+            c |= s[j] ^ blacklist[i][j];
+        }
+        c |= s[j] ^ blacklist[i][j] ^ neg;
+        if (c == 0) {
+            return 1;
+        }
+    }
+    return 0;
+}
+
 /*
  Input:
  a[0]+256*a[1]+...+256^31*a[31] = a
@@ -2912,3 +2997,25 @@ sc_reduce(unsigned char *s)
     s[30] = s11 >> 9;
     s[31] = s11 >> 17;
 }
+
+int
+sc_is_less_than_L(const unsigned char *s)
+{
+    /* 2^252+27742317777372353535851937790883648493 */
+    static const unsigned char L[32] = {
+        0xed, 0xd3, 0xf5, 0x5c, 0x1a, 0x63, 0x12, 0x58, 0xd6, 0x9c, 0xf7,
+        0xa2, 0xde, 0xf9, 0xde, 0x14, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10
+    };
+    unsigned char c = 0;
+    unsigned char n = 1;
+    unsigned int  i = 32;
+
+    do {
+        i--;
+        c |= ((s[i] - L[i]) >> 8) & n;
+        n &= ((s[i] ^ L[i]) - 1) >> 8;
+    } while (i != 0);
+
+    return (c != 0);
+}
diff --git a/src/libsodium/crypto_sign/ed25519/ref10/ed25519_ref10.h b/src/libsodium/crypto_sign/ed25519/ref10/ed25519_ref10.h
index d8a4d70e..8d93892b 100644
--- a/src/libsodium/crypto_sign/ed25519/ref10/ed25519_ref10.h
+++ b/src/libsodium/crypto_sign/ed25519/ref10/ed25519_ref10.h
@@ -15,7 +15,4 @@ int _crypto_sign_ed25519_verify_detached(const unsigned char *sig,
                                          unsigned long long   mlen,
                                          const unsigned char *pk,
                                          int prehashed);
-
-int _crypto_sign_ed25519_small_order(const unsigned char p[32], unsigned char neg);
-
 #endif
diff --git a/src/libsodium/crypto_sign/ed25519/ref10/keypair.c b/src/libsodium/crypto_sign/ed25519/ref10/keypair.c
index 271ffd7c..0e8aa885 100644
--- a/src/libsodium/crypto_sign/ed25519/ref10/keypair.c
+++ b/src/libsodium/crypto_sign/ed25519/ref10/keypair.c
@@ -16,14 +16,10 @@ crypto_sign_ed25519_scalarmult(unsigned char *q, const unsigned char *n,
     unsigned char *t = q;
     ge_p3          Q;
     ge_p3          P;
-    ge_p3          pl;
 
-    if (_crypto_sign_ed25519_small_order(p, 1) ||
-        ge_frombytes_negate_vartime(&P, p) != 0) {
-        return -1;
-    }
-    ge_mul_l(&pl, &P);
-    if (fe_isnonzero(pl.X)) {
+    if (ge_has_small_order(p, 1) != 0 ||
+        ge_frombytes_negate_vartime(&P, p) != 0 ||
+        ge_is_on_main_subgroup(&P) == 0) {
         return -1;
     }
     memmove(t, n, 32);
@@ -79,16 +75,12 @@ crypto_sign_ed25519_pk_to_curve25519(unsigned char *curve25519_pk,
                                      const unsigned char *ed25519_pk)
 {
     ge_p3 A;
-    ge_p3 pl;
     fe    x;
     fe    one_minus_y;
 
-    if (_crypto_sign_ed25519_small_order(ed25519_pk, 1) ||
-        ge_frombytes_negate_vartime(&A, ed25519_pk) != 0) {
-        return -1;
-    }
-    ge_mul_l(&pl, &A);
-    if (fe_isnonzero(pl.X)) {
+    if (ge_has_small_order(ed25519_pk, 1) != 0 ||
+        ge_frombytes_negate_vartime(&A, ed25519_pk) != 0 ||
+        ge_is_on_main_subgroup(&A) == 0) {
         return -1;
     }
     fe_1(one_minus_y);
diff --git a/src/libsodium/crypto_sign/ed25519/ref10/open.c b/src/libsodium/crypto_sign/ed25519/ref10/open.c
index 94c55e83..4a237dbf 100644
--- a/src/libsodium/crypto_sign/ed25519/ref10/open.c
+++ b/src/libsodium/crypto_sign/ed25519/ref10/open.c
@@ -10,105 +10,6 @@
 #include "private/curve25519_ref10.h"
 #include "utils.h"
 
-#ifndef ED25519_COMPAT
-static int
-crypto_sign_check_S_lt_L(const unsigned char *S)
-{
-    /* 2^252+27742317777372353535851937790883648493 */
-    static const unsigned char L[32] = {
-        0xed, 0xd3, 0xf5, 0x5c, 0x1a, 0x63, 0x12, 0x58, 0xd6, 0x9c, 0xf7,
-        0xa2, 0xde, 0xf9, 0xde, 0x14, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10
-    };
-    unsigned char c = 0;
-    unsigned char n = 1;
-    unsigned int  i = 32;
-
-    do {
-        i--;
-        c |= ((S[i] - L[i]) >> 8) & n;
-        n &= ((S[i] ^ L[i]) - 1) >> 8;
-    } while (i != 0);
-
-    return -(c == 0);
-}
-
-int
-_crypto_sign_ed25519_small_order(const unsigned char p[32], unsigned char neg)
-{
-    CRYPTO_ALIGN(16)
-    static const unsigned char blacklist[][32] = {
-        /* 0 (order 4) */
-        { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
-        /* 1 (order 1) */
-        { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
-        /* 2707385501144840649318225287225658788936804267575313519463743609750303402022
-           (order 8) */
-        { 0x26, 0xe8, 0x95, 0x8f, 0xc2, 0xb2, 0x27, 0xb0, 0x45, 0xc3, 0xf4,
-          0x89, 0xf2, 0xef, 0x98, 0xf0, 0xd5, 0xdf, 0xac, 0x05, 0xd3, 0xc6,
-          0x33, 0x39, 0xb1, 0x38, 0x02, 0x88, 0x6d, 0x53, 0xfc, 0x05 },
-        /* 55188659117513257062467267217118295137698188065244968500265048394206261417927
-           (order 8) */
-        { 0xc7, 0x17, 0x6a, 0x70, 0x3d, 0x4d, 0xd8, 0x4f, 0xba, 0x3c, 0x0b,
-          0x76, 0x0d, 0x10, 0x67, 0x0f, 0x2a, 0x20, 0x53, 0xfa, 0x2c, 0x39,
-          0xcc, 0xc6, 0x4e, 0xc7, 0xfd, 0x77, 0x92, 0xac, 0x03, 0x7a },
-        /* p-1 (order 2) */
-        { 0x13, 0xe8, 0x95, 0x8f, 0xc2, 0xb2, 0x27, 0xb0, 0x45, 0xc3, 0xf4,
-          0x89, 0xf2, 0xef, 0x98, 0xf0, 0xd5, 0xdf, 0xac, 0x05, 0xd3, 0xc6,
-          0x33, 0x39, 0xb1, 0x38, 0x02, 0x88, 0x6d, 0x53, 0xfc, 0x85 },
-        /* p (order 4) */
-        { 0xb4, 0x17, 0x6a, 0x70, 0x3d, 0x4d, 0xd8, 0x4f, 0xba, 0x3c, 0x0b,
-          0x76, 0x0d, 0x10, 0x67, 0x0f, 0x2a, 0x20, 0x53, 0xfa, 0x2c, 0x39,
-          0xcc, 0xc6, 0x4e, 0xc7, 0xfd, 0x77, 0x92, 0xac, 0x03, 0xfa },
-        /* p+1 (order 1) */
-        { 0xec, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
-        /* p+2707385501144840649318225287225658788936804267575313519463743609750303402022
-           (order 8) */
-        { 0xed, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
-        /* p+55188659117513257062467267217118295137698188065244968500265048394206261417927
-           (order 8) */
-        { 0xee, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
-        /* 2p-1 (order 2) */
-        { 0xd9, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
-        /* 2p (order 4) */
-        { 0xda, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
-        /* 2p+1 (order 1) */
-        { 0xdb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }
-    };
-    size_t        i, j;
-    unsigned char c;
-
-    neg <<= 7;
-    for (i = 0; i < sizeof blacklist / sizeof blacklist[0]; i++) {
-        c = 0;
-        for (j = 0; j < 31; j++) {
-            c |= p[j] ^ blacklist[i][j];
-        }
-        c |= p[j] ^ blacklist[i][j] ^ neg;
-        if (c == 0) {
-            return 1;
-        }
-    }
-    return 0;
-}
-#endif
-
 int
 _crypto_sign_ed25519_verify_detached(const unsigned char *sig,
                                      const unsigned char *m,
@@ -125,8 +26,8 @@ _crypto_sign_ed25519_verify_detached(const unsigned char *sig,
     ge_p2                    R;
 
 #ifndef ED25519_COMPAT
-    if (crypto_sign_check_S_lt_L(sig + 32) != 0 ||
-        _crypto_sign_ed25519_small_order(sig, 0) != 0) {
+    if (sc_is_less_than_L(sig + 32) == 0 ||
+        ge_has_small_order(sig, 0) != 0) {
         return -1;
     }
 #else
diff --git a/src/libsodium/include/sodium/private/curve25519_ref10.h b/src/libsodium/include/sodium/private/curve25519_ref10.h
index 0494c379..5728c5e7 100644
--- a/src/libsodium/include/sodium/private/curve25519_ref10.h
+++ b/src/libsodium/include/sodium/private/curve25519_ref10.h
@@ -104,7 +104,8 @@ typedef struct {
 #define ge_scalarmult_base crypto_core_curve25519_ref10_ge_scalarmult_base
 #define ge_double_scalarmult_vartime crypto_core_curve25519_ref10_ge_double_scalarmult_vartime
 #define ge_scalarmult_vartime crypto_core_curve25519_ref10_ge_scalarmult_vartime
-#define ge_mul_l crypto_core_curve25519_ref10_ge_mul_l
+#define ge_is_on_main_subgroup crypto_core_curve25519_ref10_ge_is_on_main_subgroup
+#define ge_has_small_order crypto_core_curve25519_ref10_ge_has_small_order
 
 extern void ge_tobytes(unsigned char *,const ge_p2 *);
 extern void ge_p3_tobytes(unsigned char *,const ge_p3 *);
@@ -118,7 +119,8 @@ extern void ge_scalarmult_base(ge_p3 *,const unsigned char *);
 extern void ge_double_scalarmult_vartime(ge_p2 *,const unsigned char *,const ge_p3 *,const unsigned char *);
 extern void ge_scalarmult(ge_p3 *,const unsigned char *,const ge_p3 *);
 extern void ge_scalarmult_vartime(ge_p3 *,const unsigned char *,const ge_p3 *);
-extern void ge_mul_l(ge_p3 *r, const ge_p3 *A);
+extern int ge_is_on_main_subgroup(const ge_p3 *p);
+extern int ge_has_small_order(const unsigned char s[32], unsigned char neg);
 
 /*
  The set of scalars is \Z/l
@@ -127,8 +129,10 @@ extern void ge_mul_l(ge_p3 *r, const ge_p3 *A);
 
 #define sc_reduce crypto_core_curve25519_ref10_sc_reduce
 #define sc_muladd crypto_core_curve25519_ref10_sc_muladd
+#define sc_is_less_than_L crypto_core_curve25519_ref10_sc_is_less_than_L
 
 extern void sc_reduce(unsigned char *);
 extern void sc_muladd(unsigned char *,const unsigned char *,const unsigned char *,const unsigned char *);
+extern int sc_is_less_than_L(const unsigned char *s);
 
 #endif