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### File openssl-rsakeygen-minimum-distance.patch of Package openssl-1_1_0

Index: openssl-1.1.0f/crypto/rsa/rsa_gen.c
===================================================================
--- openssl-1.1.0f.orig/crypto/rsa/rsa_gen.c	2017-05-29 13:02:47.095166778 +0200
+++ openssl-1.1.0f/crypto/rsa/rsa_gen.c	2017-05-29 13:03:29.415824383 +0200
@@ -419,6 +419,19 @@ static int rsa_builtin_keygen(RSA *rsa,
bitsp = (bits + 1) / 2;
bitsq = bits - bitsp;

+    /* prepare a maximum for p and q */
+    /* 0xB504F334 is (sqrt(2)/2)*2^32 */
+    if (!BN_set_word(r0, 0xB504F334))
+        goto err;
+    if (!BN_lshift(r0, r0, bitsp - 32))
+        goto err;
+
+    /* prepare minimum p and q difference */
+    if (!BN_one(r3))
+        goto err;
+    if (!BN_lshift(r3, r3, bitsp - 100))
+        goto err;
+
/* We need the RSA components non-NULL */
if (!rsa->n && ((rsa->n = BN_new()) == NULL))
goto err;
@@ -444,6 +457,8 @@ static int rsa_builtin_keygen(RSA *rsa,
for (;;) {
if (!BN_generate_prime_ex(rsa->p, bitsp, 0, NULL, NULL, cb))
goto err;
+        if (BN_cmp(rsa->p, r0) < 0)
+            continue;
if (!BN_sub(r2, rsa->p, BN_value_one()))
goto err;
if (!BN_gcd(r1, r2, rsa->e, ctx))
@@ -460,6 +475,13 @@ static int rsa_builtin_keygen(RSA *rsa,
if (!BN_generate_prime_ex(rsa->q, bitsq, 0, NULL, NULL, cb))
goto err;
} while (BN_cmp(rsa->p, rsa->q) == 0);
+        if (BN_cmp(rsa->q, r0) < 0)
+            continue;
+        /* check for minimum distance between p and q, 2^(bitsp-100) */
+        if (!BN_sub(r2, rsa->q, rsa->p))
+            goto err;
+        if (BN_ucmp(r2, r3) <= 0)
+            continue;
if (!BN_sub(r2, rsa->q, BN_value_one()))
goto err;
if (!BN_gcd(r1, r2, rsa->e, ctx))