Backport 'Support for DH and ECDH key exchange for QSslSocket servers…

…' from Qt 5.

See https://codereview.qt-project.org/#/c/82817/ for more info.

Qt 5 qtbase commit: 814a1c7b2b940cdf6b1716406b26063576ac0d95

src/network/ssl/qsslsocket_openssl.cpp

@@ -65,6 +65,54 @@
 #include <QtCore/qvarlengtharray.h>
 #include <QLibrary> // for loading the security lib for the CA store
 
+
+// Default DH params
+// 1024-bit MODP Group with 160-bit Prime Order Subgroup
+// From RFC 5114
+static unsigned const char dh1024_p[]={
+    0xB1,0x0B,0x8F,0x96,0xA0,0x80,0xE0,0x1D,0xDE,0x92,0xDE,0x5E,
+    0xAE,0x5D,0x54,0xEC,0x52,0xC9,0x9F,0xBC,0xFB,0x06,0xA3,0xC6,
+    0x9A,0x6A,0x9D,0xCA,0x52,0xD2,0x3B,0x61,0x60,0x73,0xE2,0x86,
+    0x75,0xA2,0x3D,0x18,0x98,0x38,0xEF,0x1E,0x2E,0xE6,0x52,0xC0,
+    0x13,0xEC,0xB4,0xAE,0xA9,0x06,0x11,0x23,0x24,0x97,0x5C,0x3C,
+    0xD4,0x9B,0x83,0xBF,0xAC,0xCB,0xDD,0x7D,0x90,0xC4,0xBD,0x70,
+    0x98,0x48,0x8E,0x9C,0x21,0x9A,0x73,0x72,0x4E,0xFF,0xD6,0xFA,
+    0xE5,0x64,0x47,0x38,0xFA,0xA3,0x1A,0x4F,0xF5,0x5B,0xCC,0xC0,
+    0xA1,0x51,0xAF,0x5F,0x0D,0xC8,0xB4,0xBD,0x45,0xBF,0x37,0xDF,
+    0x36,0x5C,0x1A,0x65,0xE6,0x8C,0xFD,0xA7,0x6D,0x4D,0xA7,0x08,
+    0xDF,0x1F,0xB2,0xBC,0x2E,0x4A,0x43,0x71
+};
+
+static unsigned const char dh1024_g[]={
+    0xA4,0xD1,0xCB,0xD5,0xC3,0xFD,0x34,0x12,0x67,0x65,0xA4,0x42,
+    0xEF,0xB9,0x99,0x05,0xF8,0x10,0x4D,0xD2,0x58,0xAC,0x50,0x7F,
+    0xD6,0x40,0x6C,0xFF,0x14,0x26,0x6D,0x31,0x26,0x6F,0xEA,0x1E,
+    0x5C,0x41,0x56,0x4B,0x77,0x7E,0x69,0x0F,0x55,0x04,0xF2,0x13,
+    0x16,0x02,0x17,0xB4,0xB0,0x1B,0x88,0x6A,0x5E,0x91,0x54,0x7F,
+    0x9E,0x27,0x49,0xF4,0xD7,0xFB,0xD7,0xD3,0xB9,0xA9,0x2E,0xE1,
+    0x90,0x9D,0x0D,0x22,0x63,0xF8,0x0A,0x76,0xA6,0xA2,0x4C,0x08,
+    0x7A,0x09,0x1F,0x53,0x1D,0xBF,0x0A,0x01,0x69,0xB6,0xA2,0x8A,
+    0xD6,0x62,0xA4,0xD1,0x8E,0x73,0xAF,0xA3,0x2D,0x77,0x9D,0x59,
+    0x18,0xD0,0x8B,0xC8,0x85,0x8F,0x4D,0xCE,0xF9,0x7C,0x2A,0x24,
+    0x85,0x5E,0x6E,0xEB,0x22,0xB3,0xB2,0xE5
+};
+
+static DH *get_dh1024()
+{
+    DH *dh = q_DH_new();
+    if (!dh)
+        return 0;
+
+    dh->p = q_BN_bin2bn(dh1024_p, sizeof(dh1024_p), 0);
+    dh->g = q_BN_bin2bn(dh1024_g, sizeof(dh1024_g), 0);
+    if (!dh->p || !dh->g) {
+        q_DH_free(dh);
+        return 0;
+    }
+
+    return dh;
+}
+
 #if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT)
 // Symbian does not seem to have the symbol for SNI defined
 #ifndef SSL_CTRL_SET_TLSEXT_HOSTNAME
@@ -443,6 +491,18 @@ bool QSslSocketBackendPrivate::initSslContext()
     if (configuration.peerVerifyDepth != 0)
         q_SSL_CTX_set_verify_depth(ctx, configuration.peerVerifyDepth);
 
+    // Set temp DH params
+    DH *dh = 0;
+    dh = get_dh1024();
+    q_SSL_CTX_set_tmp_dh(ctx, dh);
+    q_DH_free(dh);
+
+    // Set temp ECDH params
+    EC_KEY *ecdh = 0;
+    ecdh = q_EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
+    q_SSL_CTX_set_tmp_ecdh(ctx, ecdh);
+    q_EC_KEY_free(ecdh);
+
     // Create and initialize SSL session
     if (!(ssl = q_SSL_new(ctx))) {
         // ### Bad error code

src/network/ssl/qsslsocket_openssl_symbols.cpp

@@ -287,6 +287,12 @@ DEFINEFUNC(void, OPENSSL_add_all_algorithms_noconf, void, DUMMYARG, return, DUMM
 DEFINEFUNC(void, OPENSSL_add_all_algorithms_conf, void, DUMMYARG, return, DUMMYARG)
 DEFINEFUNC3(int, SSL_CTX_load_verify_locations, SSL_CTX *ctx, ctx, const char *CAfile, CAfile, const char *CApath, CApath, return 0, return)
 DEFINEFUNC(long, SSLeay, void, DUMMYARG, return 0, return)
+DEFINEFUNC(DH *, DH_new, DUMMYARG, DUMMYARG, return 0, return)
+DEFINEFUNC(void, DH_free, DH *dh, dh, return, DUMMYARG)
+DEFINEFUNC3(BIGNUM *, BN_bin2bn, const unsigned char *s, s, int len, len, BIGNUM *ret, ret, return 0
+, return)
+DEFINEFUNC(EC_KEY *, EC_KEY_new_by_curve_name, int nid, nid, return 0, return)
+DEFINEFUNC(void, EC_KEY_free, EC_KEY *ecdh, ecdh, return, DUMMYARG)
 
 #ifdef Q_OS_SYMBIAN
 #define RESOLVEFUNC(func, ordinal, lib) \
@@ -731,6 +737,11 @@ bool q_resolveOpenSslSymbols()
     RESOLVEFUNC(OPENSSL_add_all_algorithms_noconf, 1153, libs.second )
     RESOLVEFUNC(OPENSSL_add_all_algorithms_conf, 1152, libs.second )
     RESOLVEFUNC(SSLeay, 1504, libs.second )
+    RESOLVEFUNC(DH_new, 4000, libs.second )
+    RESOLVEFUNC(DH_free, 4001, libs.second )
+    RESOLVEFUNC(BN_bin2bn, 4002, libs.second )
+    RESOLVEFUNC(EC_KEY_new_by_curve_name, 4003, libs.second )
+    RESOLVEFUNC(EC_KEY_free, 4004, libs.second )
 #else // Q_OS_SYMBIAN
 #ifdef SSLEAY_MACROS
     RESOLVEFUNC(ASN1_dup)
@@ -873,6 +884,11 @@ bool q_resolveOpenSslSymbols()
     RESOLVEFUNC(OPENSSL_add_all_algorithms_conf)
     RESOLVEFUNC(SSL_CTX_load_verify_locations)
     RESOLVEFUNC(SSLeay)
+    RESOLVEFUNC(DH_new)
+    RESOLVEFUNC(DH_free)
+    RESOLVEFUNC(BN_bin2bn)
+    RESOLVEFUNC(EC_KEY_new_by_curve_name)
+    RESOLVEFUNC(EC_KEY_free)
 #endif // Q_OS_SYMBIAN
     symbolsResolved = true;
     delete libs.first;

src/network/ssl/qsslsocket_openssl_symbols_p.h

@@ -380,6 +380,17 @@ X509 *q_X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx);
 STACK_OF(X509) *q_X509_STORE_CTX_get_chain(X509_STORE_CTX *ctx);
 X509_VERIFY_PARAM *q_X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx);
 
+// Diffie-Hellman support
+DH *q_DH_new();
+void q_DH_free(DH *dh);
+BIGNUM *q_BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret);
+#define q_SSL_CTX_set_tmp_dh(ctx, dh) q_SSL_CTX_ctrl((ctx), SSL_CTRL_SET_TMP_DH, 0, (char *)dh)
+
+// EC Diffie-Hellman support
+EC_KEY *q_EC_KEY_new_by_curve_name(int nid);
+void q_EC_KEY_free(EC_KEY *ecdh);
+#define q_SSL_CTX_set_tmp_ecdh(ctx, ecdh) q_SSL_CTX_ctrl((ctx), SSL_CTRL_SET_TMP_ECDH, 0, (char *)ecdh)
+
 #define q_BIO_get_mem_data(b, pp) (int)q_BIO_ctrl(b,BIO_CTRL_INFO,0,(char *)pp)
 #define q_BIO_pending(b) (int)q_BIO_ctrl(b,BIO_CTRL_PENDING,0,NULL)
 #ifdef SSLEAY_MACROS