openssl/0076-FIPS-140-3-DRBG.patch

From 4b59d71e276243615d8fcc65bab32d83e6a602ad Mon Sep 17 00:00:00 2001
From: rpm-build <rpm-build>
Date: Mon, 31 Jul 2023 09:41:29 +0200
Subject: [PATCH 32/35] 0076-FIPS-140-3-DRBG.patch

Patch-name: 0076-FIPS-140-3-DRBG.patch
Patch-id: 76
Patch-status: |
    # Downstream only. Reseed DRBG using getrandom(GRND_RANDOM)
    # https://bugzilla.redhat.com/show_bug.cgi?id=2102541
From-dist-git-commit: 9409bc7044cf4b5773639cce20f51399888c45fd
---
 crypto/rand/prov_seed.c                       |  9 ++-
 providers/implementations/rands/crngt.c       |  6 +-
 providers/implementations/rands/drbg.c        |  3 +
 .../implementations/rands/seeding/rand_unix.c | 64 ++-----------------
 4 files changed, 20 insertions(+), 62 deletions(-)

diff --git a/crypto/rand/prov_seed.c b/crypto/rand/prov_seed.c
index 96c499c957..61c4cd8779 100644
--- a/crypto/rand/prov_seed.c
+++ b/crypto/rand/prov_seed.c
@@ -20,7 +20,14 @@ size_t ossl_rand_get_entropy(ossl_unused const OSSL_CORE_HANDLE *handle,
     size_t entropy_available;
     RAND_POOL *pool;
 
-    pool = ossl_rand_pool_new(entropy, 1, min_len, max_len);
+    /*
+     * OpenSSL still implements an internal entropy pool of
+     * some size that is hashed to get seed data.
+     * Note that this is a conditioning step for which SP800-90C requires
+     * 64 additional bits from the entropy source to claim the requested
+     * amount of entropy.
+     */
+    pool = ossl_rand_pool_new(entropy + 64, 1, min_len, max_len);
     if (pool == NULL) {
         ERR_raise(ERR_LIB_RAND, ERR_R_MALLOC_FAILURE);
         return 0;
diff --git a/providers/implementations/rands/crngt.c b/providers/implementations/rands/crngt.c
index fa4a2db14a..1f13fc759e 100644
--- a/providers/implementations/rands/crngt.c
+++ b/providers/implementations/rands/crngt.c
@@ -133,7 +133,11 @@ size_t ossl_crngt_get_entropy(PROV_DRBG *drbg,
      * to the nearest byte.  If the entropy is of less than full quality,
      * the amount required should be scaled up appropriately here.
      */
-    bytes_needed = (entropy + 7) / 8;
+    /*
+     * FIPS 140-3: the yet draft SP800-90C requires requested entropy
+     * + 128 bits during initial seeding
+     */
+    bytes_needed = (entropy + 128 + 7) / 8;
     if (bytes_needed < min_len)
         bytes_needed = min_len;
     if (bytes_needed > max_len)
diff --git a/providers/implementations/rands/drbg.c b/providers/implementations/rands/drbg.c
index ea55363bf8..423bb91157 100644
--- a/providers/implementations/rands/drbg.c
+++ b/providers/implementations/rands/drbg.c
@@ -570,6 +570,9 @@ int ossl_prov_drbg_reseed(PROV_DRBG *drbg, int prediction_resistance,
 #endif
     }
 
+#ifdef FIPS_MODULE
+    prediction_resistance = 1;
+#endif
     /* Reseed using our sources in addition */
     entropylen = get_entropy(drbg, &entropy, drbg->strength,
                              drbg->min_entropylen, drbg->max_entropylen,
diff --git a/providers/implementations/rands/seeding/rand_unix.c b/providers/implementations/rands/seeding/rand_unix.c
index cd02a0236d..98c917b6d8 100644
--- a/providers/implementations/rands/seeding/rand_unix.c
+++ b/providers/implementations/rands/seeding/rand_unix.c
@@ -48,6 +48,8 @@
 # include <fcntl.h>
 # include <unistd.h>
 # include <sys/time.h>
+# include <sys/random.h>
+# include <openssl/evp.h>
 
 static uint64_t get_time_stamp(void);
 
@@ -341,66 +343,8 @@ static ssize_t syscall_random(void *buf, size_t buflen)
      * which is way below the OSSL_SSIZE_MAX limit. Therefore sign conversion
      * between size_t and ssize_t is safe even without a range check.
      */
-
-    /*
-     * Do runtime detection to find getentropy().
-     *
-     * Known OSs that should support this:
-     * - Darwin since 16 (OSX 10.12, IOS 10.0).
-     * - Solaris since 11.3
-     * - OpenBSD since 5.6
-     * - Linux since 3.17 with glibc 2.25
-     * - FreeBSD since 12.0 (1200061)
-     *
-     * Note: Sometimes getentropy() can be provided but not implemented
-     * internally. So we need to check errno for ENOSYS
-     */
-#  if !defined(__DragonFly__) && !defined(__NetBSD__)
-#    if defined(__GNUC__) && __GNUC__>=2 && defined(__ELF__) && !defined(__hpux)
-    extern int getentropy(void *buffer, size_t length) __attribute__((weak));
-
-    if (getentropy != NULL) {
-        if (getentropy(buf, buflen) == 0)
-            return (ssize_t)buflen;
-        if (errno != ENOSYS)
-            return -1;
-    }
-#    elif defined(OPENSSL_APPLE_CRYPTO_RANDOM)
-
-    if (CCRandomGenerateBytes(buf, buflen) == kCCSuccess)
-	    return (ssize_t)buflen;
-
-    return -1;
-#    else
-    union {
-        void *p;
-        int (*f)(void *buffer, size_t length);
-    } p_getentropy;
-
-    /*
-     * We could cache the result of the lookup, but we normally don't
-     * call this function often.
-     */
-    ERR_set_mark();
-    p_getentropy.p = DSO_global_lookup("getentropy");
-    ERR_pop_to_mark();
-    if (p_getentropy.p != NULL)
-        return p_getentropy.f(buf, buflen) == 0 ? (ssize_t)buflen : -1;
-#    endif
-#  endif /* !__DragonFly__ */
-
-    /* Linux supports this since version 3.17 */
-#  if defined(__linux) && defined(__NR_getrandom)
-    return syscall(__NR_getrandom, buf, buflen, 0);
-#  elif (defined(__FreeBSD__) || defined(__NetBSD__)) && defined(KERN_ARND)
-    return sysctl_random(buf, buflen);
-#  elif (defined(__DragonFly__)  && __DragonFly_version >= 500700) \
-     || (defined(__NetBSD__) && __NetBSD_Version >= 1000000000)
-    return getrandom(buf, buflen, 0);
-#  else
-    errno = ENOSYS;
-    return -1;
-#  endif
+    /* Red Hat uses downstream patch to always seed from getrandom() */
+    return EVP_default_properties_is_fips_enabled(NULL) ? getrandom(buf, buflen, GRND_RANDOM) : getrandom(buf, buflen, 0);
 }
 #  endif    /* defined(OPENSSL_RAND_SEED_GETRANDOM) */
 
-- 
2.41.0