diff --git a/src/base58.h b/src/base58.h
index 630d6fe9..b3efd32a 100644
--- a/src/base58.h
+++ b/src/base58.h
@@ -51,7 +51,7 @@ inline std::string EncodeBase58(const unsigned char* pbegin, const unsigned char
     CBigNum rem;
     while (bn > bn0)
     {
-        if (!BN_div(&dv, &rem, &bn, &bn58, pctx))
+        if (!BN_div(dv.bn, rem.bn, bn.bn, bn58.bn, pctx))
             throw bignum_error("EncodeBase58 : BN_div failed");
         bn = dv;
         unsigned int c = rem.getulong();
@@ -98,7 +98,7 @@ inline bool DecodeBase58(const char* psz, std::vector<unsigned char>& vchRet)
             break;
         }
         bnChar.setulong(p1 - pszBase58);
-        if (!BN_mul(&bn, &bn, &bn58, pctx))
+        if (!BN_mul(bn.bn, bn.bn, bn58.bn, pctx))
             throw bignum_error("DecodeBase58 : BN_mul failed");
         bn += bnChar;
     }
diff --git a/src/bignum.h b/src/bignum.h
index 0881807d..63720274 100644
--- a/src/bignum.h
+++ b/src/bignum.h
@@ -48,75 +48,76 @@ public:
 
 
 /** C++ wrapper for BIGNUM (OpenSSL bignum) */
-class CBigNum : public BIGNUM
+class CBigNum
 {
 public:
+    BIGNUM *bn;
     CBigNum()
     {
-        BN_init(this);
+        this->bn = BN_new();
     }
 
     CBigNum(const CBigNum& b)
     {
-        BN_init(this);
-        if (!BN_copy(this, &b))
+        this->bn = BN_new();
+        if (!BN_copy(this->bn, b.bn))
         {
-            BN_clear_free(this);
+            BN_clear_free(this->bn);
             throw bignum_error("CBigNum::CBigNum(const CBigNum&) : BN_copy failed");
         }
     }
 
     CBigNum& operator=(const CBigNum& b)
     {
-        if (!BN_copy(this, &b))
+        if (!BN_copy(this->bn, b.bn))
             throw bignum_error("CBigNum::operator= : BN_copy failed");
         return (*this);
     }
 
     ~CBigNum()
     {
-        BN_clear_free(this);
+        BN_clear_free(this->bn);
     }
 
     //CBigNum(char n) is not portable.  Use 'signed char' or 'unsigned char'.
-    CBigNum(signed char n)      { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
-    CBigNum(short n)            { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
-    CBigNum(int n)              { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
-    CBigNum(long n)             { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
-    CBigNum(int64 n)            { BN_init(this); setint64(n); }
-    CBigNum(unsigned char n)    { BN_init(this); setulong(n); }
-    CBigNum(unsigned short n)   { BN_init(this); setulong(n); }
-    CBigNum(unsigned int n)     { BN_init(this); setulong(n); }
-    CBigNum(unsigned long n)    { BN_init(this); setulong(n); }
-    CBigNum(uint64 n)           { BN_init(this); setuint64(n); }
-    explicit CBigNum(uint256 n) { BN_init(this); setuint256(n); }
+    CBigNum(signed char n)      { this->bn = BN_new(); if (n >= 0) setulong(n); else setint64(n); }
+    CBigNum(short n)            { this->bn = BN_new(); if (n >= 0) setulong(n); else setint64(n); }
+    CBigNum(int n)              { this->bn = BN_new(); if (n >= 0) setulong(n); else setint64(n); }
+    CBigNum(long n)             { this->bn = BN_new(); if (n >= 0) setulong(n); else setint64(n); }
+    CBigNum(int64 n)            { this->bn = BN_new(); setint64(n); }
+    CBigNum(unsigned char n)    { this->bn = BN_new(); setulong(n); }
+    CBigNum(unsigned short n)   { this->bn = BN_new(); setulong(n); }
+    CBigNum(unsigned int n)     { this->bn = BN_new(); setulong(n); }
+    CBigNum(unsigned long n)    { this->bn = BN_new(); setulong(n); }
+    CBigNum(uint64 n)           { this->bn = BN_new(); setuint64(n); }
+    explicit CBigNum(uint256 n) { this->bn = BN_new(); setuint256(n); }
 
     explicit CBigNum(const std::vector<unsigned char>& vch)
     {
-        BN_init(this);
+        this->bn = BN_new();
         setvch(vch);
     }
 
     void setulong(unsigned long n)
     {
-        if (!BN_set_word(this, n))
+        if (!BN_set_word(this->bn, n))
             throw bignum_error("CBigNum conversion from unsigned long : BN_set_word failed");
     }
 
     unsigned long getulong() const
     {
-        return BN_get_word(this);
+        return BN_get_word(this->bn);
     }
 
     unsigned int getuint() const
     {
-        return BN_get_word(this);
+        return BN_get_word(this->bn);
     }
 
     int getint() const
     {
-        unsigned long n = BN_get_word(this);
-        if (!BN_is_negative(this))
+        unsigned long n = BN_get_word(this->bn);
+        if (!BN_is_negative(this->bn))
             return (n > (unsigned long)std::numeric_limits<int>::max() ? std::numeric_limits<int>::max() : n);
         else
             return (n > (unsigned long)std::numeric_limits<int>::max() ? std::numeric_limits<int>::min() : -(int)n);
@@ -164,7 +165,7 @@ public:
         pch[1] = (nSize >> 16) & 0xff;
         pch[2] = (nSize >> 8) & 0xff;
         pch[3] = (nSize) & 0xff;
-        BN_mpi2bn(pch, p - pch, this);
+        BN_mpi2bn(pch, p - pch, this->bn);
     }
 
     void setuint64(uint64 n)
@@ -191,7 +192,7 @@ public:
         pch[1] = (nSize >> 16) & 0xff;
         pch[2] = (nSize >> 8) & 0xff;
         pch[3] = (nSize) & 0xff;
-        BN_mpi2bn(pch, p - pch, this);
+        BN_mpi2bn(pch, p - pch, this->bn);
     }
 
     void setuint256(uint256 n)
@@ -219,16 +220,16 @@ public:
         pch[1] = (nSize >> 16) & 0xff;
         pch[2] = (nSize >> 8) & 0xff;
         pch[3] = (nSize >> 0) & 0xff;
-        BN_mpi2bn(pch, p - pch, this);
+        BN_mpi2bn(pch, p - pch, this->bn);
     }
 
     uint256 getuint256() const
     {
-        unsigned int nSize = BN_bn2mpi(this, NULL);
+        unsigned int nSize = BN_bn2mpi(this->bn, NULL);
         if (nSize < 4)
             return 0;
         std::vector<unsigned char> vch(nSize);
-        BN_bn2mpi(this, &vch[0]);
+        BN_bn2mpi(this->bn, &vch[0]);
         if (vch.size() > 4)
             vch[4] &= 0x7f;
         uint256 n = 0;
@@ -249,16 +250,16 @@ public:
         vch2[3] = (nSize >> 0) & 0xff;
         // swap data to big endian
         reverse_copy(vch.begin(), vch.end(), vch2.begin() + 4);
-        BN_mpi2bn(&vch2[0], vch2.size(), this);
+        BN_mpi2bn(&vch2[0], vch2.size(), this->bn);
     }
 
     std::vector<unsigned char> getvch() const
     {
-        unsigned int nSize = BN_bn2mpi(this, NULL);
+        unsigned int nSize = BN_bn2mpi(this->bn, NULL);
         if (nSize <= 4)
             return std::vector<unsigned char>();
         std::vector<unsigned char> vch(nSize);
-        BN_bn2mpi(this, &vch[0]);
+        BN_bn2mpi(this->bn, &vch[0]);
         vch.erase(vch.begin(), vch.begin() + 4);
         reverse(vch.begin(), vch.end());
         return vch;
@@ -294,28 +295,28 @@ public:
         if (nSize <= 3)
         {
             nWord >>= 8*(3-nSize);
-            BN_set_word(this, nWord);
+            BN_set_word(this->bn, nWord);
         }
         else
         {
-            BN_set_word(this, nWord);
-            BN_lshift(this, this, 8*(nSize-3));
+            BN_set_word(this->bn, nWord);
+            BN_lshift(this->bn, this->bn, 8*(nSize-3));
         }
-        BN_set_negative(this, fNegative);
+        BN_set_negative(this->bn, fNegative);
         return *this;
     }
 
     unsigned int GetCompact() const
     {
-        unsigned int nSize = BN_num_bytes(this);
+        unsigned int nSize = BN_num_bytes(this->bn);
         unsigned int nCompact = 0;
         if (nSize <= 3)
-            nCompact = BN_get_word(this) << 8*(3-nSize);
+            nCompact = BN_get_word(this->bn) << 8*(3-nSize);
         else
         {
             CBigNum bn;
-            BN_rshift(&bn, this, 8*(nSize-3));
-            nCompact = BN_get_word(&bn);
+            BN_rshift(bn.bn, this->bn, 8*(nSize-3));
+            nCompact = BN_get_word(bn.bn);
         }
         // The 0x00800000 bit denotes the sign.
         // Thus, if it is already set, divide the mantissa by 256 and increase the exponent.
@@ -325,7 +326,7 @@ public:
             nSize++;
         }
         nCompact |= nSize << 24;
-        nCompact |= (BN_is_negative(this) ? 0x00800000 : 0);
+        nCompact |= (BN_is_negative(this->bn) ? 0x00800000 : 0);
         return nCompact;
     }
 
@@ -366,20 +367,20 @@ public:
         CBigNum bn0 = 0;
         std::string str;
         CBigNum bn = *this;
-        BN_set_negative(&bn, false);
+        BN_set_negative(bn.bn, false);
         CBigNum dv;
         CBigNum rem;
-        if (BN_cmp(&bn, &bn0) == 0)
+        if (BN_cmp(bn.bn, bn0.bn) == 0)
             return "0";
-        while (BN_cmp(&bn, &bn0) > 0)
+        while (BN_cmp(bn.bn, bn0.bn) > 0)
         {
-            if (!BN_div(&dv, &rem, &bn, &bnBase, pctx))
+            if (!BN_div(dv.bn, rem.bn, bn.bn, bnBase.bn, pctx))
                 throw bignum_error("CBigNum::ToString() : BN_div failed");
             bn = dv;
             unsigned int c = rem.getulong();
             str += "0123456789abcdef"[c];
         }
-        if (BN_is_negative(this))
+        if (BN_is_negative(this->bn))
             str += "-";
         reverse(str.begin(), str.end());
         return str;
@@ -412,12 +413,12 @@ public:
 
     bool operator!() const
     {
-        return BN_is_zero(this);
+        return BN_is_zero(this->bn);
     }
 
     CBigNum& operator+=(const CBigNum& b)
     {
-        if (!BN_add(this, this, &b))
+        if (!BN_add(this->bn, this->bn, b.bn))
             throw bignum_error("CBigNum::operator+= : BN_add failed");
         return *this;
     }
@@ -431,7 +432,7 @@ public:
     CBigNum& operator*=(const CBigNum& b)
     {
         CAutoBN_CTX pctx;
-        if (!BN_mul(this, this, &b, pctx))
+        if (!BN_mul(this->bn, this->bn, b.bn, pctx))
             throw bignum_error("CBigNum::operator*= : BN_mul failed");
         return *this;
     }
@@ -450,7 +451,7 @@ public:
 
     CBigNum& operator<<=(unsigned int shift)
     {
-        if (!BN_lshift(this, this, shift))
+        if (!BN_lshift(this->bn, this->bn, shift))
             throw bignum_error("CBigNum:operator<<= : BN_lshift failed");
         return *this;
     }
@@ -461,13 +462,13 @@ public:
         //   if built on ubuntu 9.04 or 9.10, probably depends on version of OpenSSL
         CBigNum a = 1;
         a <<= shift;
-        if (BN_cmp(&a, this) > 0)
+        if (BN_cmp(a.bn, this->bn) > 0)
         {
             *this = 0;
             return *this;
         }
 
-        if (!BN_rshift(this, this, shift))
+        if (!BN_rshift(this->bn, this->bn, shift))
             throw bignum_error("CBigNum:operator>>= : BN_rshift failed");
         return *this;
     }
@@ -476,7 +477,7 @@ public:
     CBigNum& operator++()
     {
         // prefix operator
-        if (!BN_add(this, this, BN_value_one()))
+        if (!BN_add(this->bn, this->bn, BN_value_one()))
             throw bignum_error("CBigNum::operator++ : BN_add failed");
         return *this;
     }
@@ -493,7 +494,7 @@ public:
     {
         // prefix operator
         CBigNum r;
-        if (!BN_sub(&r, this, BN_value_one()))
+        if (!BN_sub(r.bn, this->bn, BN_value_one()))
             throw bignum_error("CBigNum::operator-- : BN_sub failed");
         *this = r;
         return *this;
@@ -518,7 +519,7 @@ public:
 inline const CBigNum operator+(const CBigNum& a, const CBigNum& b)
 {
     CBigNum r;
-    if (!BN_add(&r, &a, &b))
+    if (!BN_add(r.bn, a.bn, b.bn))
         throw bignum_error("CBigNum::operator+ : BN_add failed");
     return r;
 }
@@ -526,7 +527,7 @@ inline const CBigNum operator+(const CBigNum& a, const CBigNum& b)
 inline const CBigNum operator-(const CBigNum& a, const CBigNum& b)
 {
     CBigNum r;
-    if (!BN_sub(&r, &a, &b))
+    if (!BN_sub(r.bn, a.bn, b.bn))
         throw bignum_error("CBigNum::operator- : BN_sub failed");
     return r;
 }
@@ -534,7 +535,7 @@ inline const CBigNum operator-(const CBigNum& a, const CBigNum& b)
 inline const CBigNum operator-(const CBigNum& a)
 {
     CBigNum r(a);
-    BN_set_negative(&r, !BN_is_negative(&r));
+    BN_set_negative(r.bn, !BN_is_negative(r.bn));
     return r;
 }
 
@@ -542,7 +543,7 @@ inline const CBigNum operator*(const CBigNum& a, const CBigNum& b)
 {
     CAutoBN_CTX pctx;
     CBigNum r;
-    if (!BN_mul(&r, &a, &b, pctx))
+    if (!BN_mul(r.bn, a.bn, b.bn, pctx))
         throw bignum_error("CBigNum::operator* : BN_mul failed");
     return r;
 }
@@ -551,7 +552,7 @@ inline const CBigNum operator/(const CBigNum& a, const CBigNum& b)
 {
     CAutoBN_CTX pctx;
     CBigNum r;
-    if (!BN_div(&r, NULL, &a, &b, pctx))
+    if (!BN_div(r.bn, NULL, a.bn, b.bn, pctx))
         throw bignum_error("CBigNum::operator/ : BN_div failed");
     return r;
 }
@@ -560,7 +561,7 @@ inline const CBigNum operator%(const CBigNum& a, const CBigNum& b)
 {
     CAutoBN_CTX pctx;
     CBigNum r;
-    if (!BN_mod(&r, &a, &b, pctx))
+    if (!BN_mod(r.bn, a.bn, b.bn, pctx))
         throw bignum_error("CBigNum::operator% : BN_div failed");
     return r;
 }
@@ -568,7 +569,7 @@ inline const CBigNum operator%(const CBigNum& a, const CBigNum& b)
 inline const CBigNum operator<<(const CBigNum& a, unsigned int shift)
 {
     CBigNum r;
-    if (!BN_lshift(&r, &a, shift))
+    if (!BN_lshift(r.bn, a.bn, shift))
         throw bignum_error("CBigNum:operator<< : BN_lshift failed");
     return r;
 }
@@ -580,11 +581,11 @@ inline const CBigNum operator>>(const CBigNum& a, unsigned int shift)
     return r;
 }
 
-inline bool operator==(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) == 0); }
-inline bool operator!=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) != 0); }
-inline bool operator<=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) <= 0); }
-inline bool operator>=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) >= 0); }
-inline bool operator<(const CBigNum& a, const CBigNum& b)  { return (BN_cmp(&a, &b) < 0); }
-inline bool operator>(const CBigNum& a, const CBigNum& b)  { return (BN_cmp(&a, &b) > 0); }
+inline bool operator==(const CBigNum& a, const CBigNum& b) { return (BN_cmp(a.bn, b.bn) == 0); }
+inline bool operator!=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(a.bn, b.bn) != 0); }
+inline bool operator<=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(a.bn, b.bn) <= 0); }
+inline bool operator>=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(a.bn, b.bn) >= 0); }
+inline bool operator<(const CBigNum& a, const CBigNum& b)  { return (BN_cmp(a.bn, b.bn) < 0); }
+inline bool operator>(const CBigNum& a, const CBigNum& b)  { return (BN_cmp(a.bn, b.bn) > 0); }
 
 #endif
diff --git a/src/clientversion.h b/src/clientversion.h
index 6b806694..bdc660eb 100644
--- a/src/clientversion.h
+++ b/src/clientversion.h
@@ -8,7 +8,7 @@
 // These need to be macros, as version.cpp's and bitcoin-qt.rc's voodoo requires it
 #define CLIENT_VERSION_MAJOR       0
 #define CLIENT_VERSION_MINOR       9
-#define CLIENT_VERSION_REVISION    39
+#define CLIENT_VERSION_REVISION    40
 #define CLIENT_VERSION_BUILD       0
 
 // Set to true for release, false for prerelease or test build
diff --git a/src/key.cpp b/src/key.cpp
index ee3aacea..d3821ae4 100644
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -87,7 +87,13 @@ int ECDSA_SIG_recover_key_GFp(EC_KEY *eckey, ECDSA_SIG *ecsig, const unsigned ch
     x = BN_CTX_get(ctx);
     if (!BN_copy(x, order)) { ret=-1; goto err; }
     if (!BN_mul_word(x, i)) { ret=-1; goto err; }
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
     if (!BN_add(x, x, ecsig->r)) { ret=-1; goto err; }
+#else
+    const BIGNUM *ecsig_r, *ecsig_s;
+    ECDSA_SIG_get0(ecsig, &ecsig_r, &ecsig_s);
+    if (!BN_add(x, x, ecsig_r)) { ret=-1; goto err; }
+#endif
     field = BN_CTX_get(ctx);
     if (!EC_GROUP_get_curve_GFp(group, field, NULL, NULL, ctx)) { ret=-2; goto err; }
     if (BN_cmp(x, field) >= 0) { ret=0; goto err; }
@@ -108,9 +114,17 @@ int ECDSA_SIG_recover_key_GFp(EC_KEY *eckey, ECDSA_SIG *ecsig, const unsigned ch
     if (!BN_zero(zero)) { ret=-1; goto err; }
     if (!BN_mod_sub(e, zero, e, order, ctx)) { ret=-1; goto err; }
     rr = BN_CTX_get(ctx);
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
     if (!BN_mod_inverse(rr, ecsig->r, order, ctx)) { ret=-1; goto err; }
+#else
+    if (!BN_mod_inverse(rr, ecsig_r, order, ctx)) { ret=-1; goto err; }
+#endif
     sor = BN_CTX_get(ctx);
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
     if (!BN_mod_mul(sor, ecsig->s, rr, order, ctx)) { ret=-1; goto err; }
+#else
+    if (!BN_mod_mul(sor, ecsig_s, rr, order, ctx)) { ret=-1; goto err; }
+#endif
     eor = BN_CTX_get(ctx);
     if (!BN_mod_mul(eor, e, rr, order, ctx)) { ret=-1; goto err; }
     if (!EC_POINT_mul(group, Q, eor, R, sor, ctx)) { ret=-2; goto err; }
@@ -162,13 +176,16 @@ public:
     }
 
     void SetSecretBytes(const unsigned char vch[32]) {
-        BIGNUM bn;
-        BN_init(&bn);
-        bool check = BN_bin2bn(vch, 32, &bn);
+        BIGNUM *bn;
+        bn = BN_new();
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
+        BN_init(bn);
+#endif
+        bool check = BN_bin2bn(vch, 32, bn);
         assert(check);
-        check = EC_KEY_regenerate_key(pkey, &bn);
+        check = EC_KEY_regenerate_key(pkey, bn);
         assert(check);
-        BN_clear_free(&bn);
+        BN_clear_free(bn);
     }
 
     void GetPrivKey(CPrivKey &privkey, bool fCompressed) {
@@ -231,8 +248,15 @@ public:
         if (sig==NULL)
             return false;
         memset(p64, 0, 64);
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
         int nBitsR = BN_num_bits(sig->r);
         int nBitsS = BN_num_bits(sig->s);
+#else
+        const BIGNUM *sig_r, *sig_s;
+        ECDSA_SIG_get0(sig, &sig_r, &sig_s);
+        int nBitsR = BN_num_bits(sig_r);
+        int nBitsS = BN_num_bits(sig_s);
+#endif
         if (nBitsR <= 256 && nBitsS <= 256) {
             CPubKey pubkey;
             GetPubKey(pubkey, true);
@@ -249,8 +273,14 @@ public:
                 }
             }
             assert(fOk);
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
             BN_bn2bin(sig->r,&p64[32-(nBitsR+7)/8]);
             BN_bn2bin(sig->s,&p64[64-(nBitsS+7)/8]);
+#else
+            ECDSA_SIG_get0(sig, &sig_r, &sig_s);
+            BN_bn2bin(sig_r,&p64[32-(nBitsR+7)/8]);
+            BN_bn2bin(sig_s,&p64[64-(nBitsS+7)/8]);
+#endif
         }
         ECDSA_SIG_free(sig);
         return fOk;
@@ -265,8 +295,16 @@ public:
         if (rec<0 || rec>=3)
             return false;
         ECDSA_SIG *sig = ECDSA_SIG_new();
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
         BN_bin2bn(&p64[0],  32, sig->r);
         BN_bin2bn(&p64[32], 32, sig->s);
+#else
+        BIGNUM *sig_r = BN_new();
+        BIGNUM *sig_s = BN_new();
+        BN_bin2bn(&p64[0],  32, sig_r);
+        BN_bin2bn(&p64[32], 32, sig_s);
+        ECDSA_SIG_set0(sig, sig_r, sig_s);
+#endif
         bool ret = ECDSA_SIG_recover_key_GFp(pkey, sig, (unsigned char*)&hash, sizeof(hash), rec, 0) == 1;
         ECDSA_SIG_free(sig);
         return ret;
@@ -460,8 +498,12 @@ public:
         EVP_CIPHER_CTX_free(cipher);
 
         // Generate an authenticated hash which can be used to validate the data during decryption.
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
         HMAC_CTX hmac;
         HMAC_CTX_init(&hmac);
+#else
+        HMAC_CTX *hmac = HMAC_CTX_new();
+#endif
         unsigned int mac_length = cryptex.mac.size();
 
         // At the moment we are generating the hash using encrypted data. At some point we may want to validate the original text instead.
@@ -470,18 +512,32 @@ public:
 	HMAC_Update(&hmac, reinterpret_cast<const unsigned char *>(cryptex.body.data()), cryptex.body.size());
 	HMAC_Final(&hmac, reinterpret_cast<unsigned char *>(&cryptex.mac[0]), &mac_length);
 #else
+ #if (OPENSSL_VERSION_NUMBER < 0x10100000)
         if (HMAC_Init_ex(&hmac, envelope_key + key_length, key_length, ECIES_HASHER, NULL) != 1 ||
             HMAC_Update(&hmac, reinterpret_cast<const unsigned char *>(cryptex.body.data()), cryptex.body.size()) != 1 ||
             HMAC_Final(&hmac, reinterpret_cast<unsigned char *>(&cryptex.mac[0]), &mac_length) != 1) {
+ #else
+        if (HMAC_Init_ex(hmac, envelope_key + key_length, key_length, ECIES_HASHER, NULL) != 1 ||
+            HMAC_Update(hmac, reinterpret_cast<const unsigned char *>(cryptex.body.data()), cryptex.body.size()) != 1 ||
+            HMAC_Final(hmac, reinterpret_cast<unsigned char *>(&cryptex.mac[0]), &mac_length) != 1) {
+ #endif
 #ifdef DEBUG_ECIES
                 printf("Unable to generate a data authentication code.\n");
 #endif
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
                 HMAC_CTX_cleanup(&hmac);
+#else
+                HMAC_CTX_free(hmac);
+#endif
                 return false;
         }
 #endif
 
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
         HMAC_CTX_cleanup(&hmac);
+#else
+        HMAC_CTX_free(hmac);
+#endif
         return true;
 
     }
@@ -575,8 +631,12 @@ public:
         EC_KEY_free(ephemeral);
 
         // Use the authenticated hash of the ciphered data to ensure it was not modified after being encrypted.
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
         HMAC_CTX hmac;
         HMAC_CTX_init(&hmac);
+#else
+        HMAC_CTX *hmac = HMAC_CTX_new();
+#endif
         unsigned int mac_length = EVP_MAX_MD_SIZE;
         unsigned char md[EVP_MAX_MD_SIZE];
 
@@ -586,18 +646,33 @@ public:
         HMAC_Update(&hmac, reinterpret_cast<const unsigned char *>(cryptex.body.data()), cryptex.body.size());
 	HMAC_Final(&hmac, md, &mac_length);
 #else
+ #if (OPENSSL_VERSION_NUMBER < 0x10100000)
         if (HMAC_Init_ex(&hmac, envelope_key + key_length, key_length, ECIES_HASHER, NULL) != 1 ||
             HMAC_Update(&hmac, reinterpret_cast<const unsigned char *>(cryptex.body.data()), cryptex.body.size()) != 1 ||
             HMAC_Final(&hmac, md, &mac_length) != 1) {
+ #else
+        if (HMAC_Init_ex(hmac, envelope_key + key_length, key_length, ECIES_HASHER, NULL) != 1 ||
+            HMAC_Update(hmac, reinterpret_cast<const unsigned char *>(cryptex.body.data()), cryptex.body.size()) != 1 ||
+            HMAC_Final(hmac, md, &mac_length) != 1) {
+ #endif
 #ifdef DEBUG_ECIES
                 printf("Unable to generate a data authentication code.\n");
 #endif
+
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
                 HMAC_CTX_cleanup(&hmac);
+#else
+                HMAC_CTX_free(hmac);
+#endif
                 return false;
         }
 #endif
 
+#if (OPENSSL_VERSION_NUMBER < 0x10100000)
         HMAC_CTX_cleanup(&hmac);
+#else
+        HMAC_CTX_free(hmac);
+#endif
 
         // We can use the generated hash to ensure the encrypted data was not altered after being encrypted.
         if (mac_length != cryptex.mac.size() || memcmp(md, cryptex.mac.data(), mac_length)) {