FIPS AES_GCM IV gen changes
authorShane Lontis <shane.lontis@oracle.com>
Wed, 20 Feb 2019 22:27:25 +0000 (08:27 +1000)
committerPauli <paul.dale@oracle.com>
Wed, 6 Mar 2019 21:30:04 +0000 (07:30 +1000)
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/8393)

crypto/evp/e_aes.c
test/aesgcmtest.c [new file with mode: 0644]
test/build.info
test/recipes/30-test_aesgcm.t [new file with mode: 0644]

index 3d2068c..5b473bc 100644 (file)
@@ -44,6 +44,7 @@ typedef struct {
     int ivlen;                  /* IV length */
     int taglen;
     int iv_gen;                 /* It is OK to generate IVs */
+    int iv_gen_rand;            /* No IV was specified, so generate a rand IV */
     int tls_aad_len;            /* TLS AAD length */
     uint64_t tls_enc_records;   /* Number of TLS records encrypted */
     ctr128_f ctr;
@@ -1396,7 +1397,7 @@ static int s390x_aes_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
                                     (OPENSSL_s390xcap_P.kma[0] &       \
                                      S390X_CAPBIT(S390X_AES_256)))
 
-/* iv + padding length for iv lenghts != 12 */
+/* iv + padding length for iv lengths != 12 */
 # define S390X_gcm_ivpadlen(i) ((((i) + 15) >> 4 << 4) + 16)
 
 /*-
@@ -2890,7 +2891,7 @@ static int aes_gcm_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr)
         return 1;
 
     case EVP_CTRL_GET_IV:
-        if (gctx->iv_gen != 1)
+        if (gctx->iv_gen != 1 && gctx->iv_gen_rand != 1)
             return 0;
         if (gctx->ivlen != arg)
             return 0;
@@ -3202,10 +3203,35 @@ static int aes_gcm_tls_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
     return rv;
 }
 
+#ifdef FIPS_MODE
+/*
+ * See SP800-38D (GCM) Section 8 "Uniqueness requirement on IVS and keys"
+ *
+ * See also 8.2.2 RBG-based construction.
+ * Random construction consists of a free field (which can be NULL) and a
+ * random field which will use a DRBG that can return at least 96 bits of
+ * entropy strength. (The DRBG must be seeded by the FIPS module).
+ */
+static int aes_gcm_iv_generate(EVP_AES_GCM_CTX *gctx, int offset)
+{
+    int sz = gctx->ivlen - offset;
+
+    /* Must be at least 96 bits */
+    if (sz <= 0 || gctx->ivlen < 12)
+        return 0;
+
+    /* Use DRBG to generate random iv */
+    if (RAND_bytes(gctx->iv + offset, sz) <= 0)
+        return 0;
+    return 1;
+}
+#endif /* FIPS_MODE */
+
 static int aes_gcm_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
                           const unsigned char *in, size_t len)
 {
     EVP_AES_GCM_CTX *gctx = EVP_C_DATA(EVP_AES_GCM_CTX,ctx);
+
     /* If not set up, return error */
     if (!gctx->key_set)
         return -1;
@@ -3213,8 +3239,25 @@ static int aes_gcm_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
     if (gctx->tls_aad_len >= 0)
         return aes_gcm_tls_cipher(ctx, out, in, len);
 
+#ifdef FIPS_MODE
+    /*
+     * FIPS requires generation of AES-GCM IV's inside the FIPS module.
+     * The IV can still be set externally (the security policy will state that
+     * this is not FIPS compliant). There are some applications
+     * where setting the IV externally is the only option available.
+     */
+    if (!gctx->iv_set) {
+        if (!ctx->encrypt || !aes_gcm_iv_generate(gctx, 0))
+            return -1;
+        CRYPTO_gcm128_setiv(&gctx->gcm, gctx->iv, gctx->ivlen);
+        gctx->iv_set = 1;
+        gctx->iv_gen_rand = 1;
+    }
+#else
     if (!gctx->iv_set)
         return -1;
+#endif /* FIPS_MODE */
+
     if (in) {
         if (out == NULL) {
             if (CRYPTO_gcm128_aad(&gctx->gcm, in, len))
diff --git a/test/aesgcmtest.c b/test/aesgcmtest.c
new file mode 100644 (file)
index 0000000..c616438
--- /dev/null
@@ -0,0 +1,123 @@
+/*
+ * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/evp.h>
+#include "testutil.h"
+
+static const unsigned char gcm_key[] = {
+    0xee, 0xbc, 0x1f, 0x57, 0x48, 0x7f, 0x51, 0x92, 0x1c, 0x04, 0x65, 0x66,
+    0x5f, 0x8a, 0xe6, 0xd1, 0x65, 0x8b, 0xb2, 0x6d, 0xe6, 0xf8, 0xa0, 0x69,
+    0xa3, 0x52, 0x02, 0x93, 0xa5, 0x72, 0x07, 0x8f
+};
+static const unsigned char gcm_iv[] = {
+    0x99, 0xaa, 0x3e, 0x68, 0xed, 0x81, 0x73, 0xa0, 0xee, 0xd0, 0x66, 0x84
+};
+static const unsigned char gcm_pt[] = {
+    0xf5, 0x6e, 0x87, 0x05, 0x5b, 0xc3, 0x2d, 0x0e, 0xeb, 0x31, 0xb2, 0xea,
+    0xcc, 0x2b, 0xf2, 0xa5
+};
+static const unsigned char gcm_aad[] = {
+    0x4d, 0x23, 0xc3, 0xce, 0xc3, 0x34, 0xb4, 0x9b, 0xdb, 0x37, 0x0c, 0x43,
+    0x7f, 0xec, 0x78, 0xde
+};
+static const unsigned char gcm_ct[] = {
+    0xf7, 0x26, 0x44, 0x13, 0xa8, 0x4c, 0x0e, 0x7c, 0xd5, 0x36, 0x86, 0x7e,
+    0xb9, 0xf2, 0x17, 0x36
+};
+static const unsigned char gcm_tag[] = {
+    0x67, 0xba, 0x05, 0x10, 0x26, 0x2a, 0xe4, 0x87, 0xd7, 0x37, 0xee, 0x62,
+    0x98, 0xf7, 0x7e, 0x0c
+};
+
+static int do_encrypt(unsigned char *iv_gen, unsigned char *ct, int *ct_len,
+                      unsigned char *tag, int *tag_len)
+{
+    int ret = 0;
+    EVP_CIPHER_CTX *ctx = NULL;
+    int outlen;
+    unsigned char outbuf[64];
+
+    *tag_len = 16;
+    ret = TEST_ptr(ctx = EVP_CIPHER_CTX_new())
+          && TEST_true(EVP_EncryptInit_ex(ctx, EVP_aes_256_gcm(), NULL, NULL,
+                                          NULL) > 0)
+          && TEST_true(EVP_EncryptInit_ex(ctx, NULL, NULL, gcm_key,
+                                          iv_gen != NULL ? NULL : gcm_iv) > 0)
+          && TEST_true(EVP_EncryptUpdate(ctx, NULL, &outlen, gcm_aad,
+                                         sizeof(gcm_aad)) > 0)
+          && TEST_true(EVP_EncryptUpdate(ctx, ct, ct_len, gcm_pt,
+                                         sizeof(gcm_pt)) > 0)
+          && TEST_true(EVP_EncryptFinal_ex(ctx, outbuf, &outlen) > 0)
+          && TEST_true(EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, 16,
+                                           tag) > 0)
+          && TEST_true(iv_gen == NULL
+                  || EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GET_IV, 12, iv_gen) > 0);
+    EVP_CIPHER_CTX_free(ctx);
+    return ret;
+}
+
+static int do_decrypt(const unsigned char *iv, const unsigned char *ct,
+                      int ct_len, const unsigned char *tag, int tag_len)
+{
+    int ret = 0;
+    EVP_CIPHER_CTX *ctx = NULL;
+    int outlen, ptlen;
+    unsigned char pt[32];
+    unsigned char outbuf[32];
+
+    ret = TEST_ptr(ctx = EVP_CIPHER_CTX_new())
+              && TEST_true(EVP_DecryptInit_ex(ctx, EVP_aes_256_gcm(), NULL,
+                                              NULL, NULL) > 0)
+              && TEST_true(EVP_DecryptInit_ex(ctx, NULL, NULL, gcm_key, iv) > 0)
+              && TEST_true(EVP_DecryptUpdate(ctx, NULL, &outlen, gcm_aad,
+                                             sizeof(gcm_aad)) > 0)
+              && TEST_true(EVP_DecryptUpdate(ctx, pt, &ptlen, ct,
+                                             ct_len) > 0)
+              && TEST_true(EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG,
+                                               tag_len, (void *)tag) > 0)
+              && TEST_true(EVP_DecryptFinal_ex(ctx, outbuf, &outlen) > 0)
+              && TEST_mem_eq(gcm_pt, sizeof(gcm_pt), pt, ptlen);
+
+    EVP_CIPHER_CTX_free(ctx);
+    return ret;
+}
+
+static int kat_test(void)
+{
+    unsigned char tag[32];
+    unsigned char ct[32];
+    int ctlen = 0, taglen = 0;
+
+    return do_encrypt(NULL, ct, &ctlen, tag, &taglen)
+           && TEST_mem_eq(gcm_ct, sizeof(gcm_ct), ct, ctlen)
+           && TEST_mem_eq(gcm_tag, sizeof(gcm_tag), tag, taglen)
+           && do_decrypt(gcm_iv, ct, ctlen, tag, taglen);
+}
+
+#ifdef FIPS_MODE
+static int ivgen_test(void)
+{
+    unsigned char iv_gen[16];
+    unsigned char tag[32];
+    unsigned char ct[32];
+    int ctlen = 0, taglen = 0;
+
+    return do_encrypt(iv_gen, ct, &ctlen, tag, &taglen)
+           && do_decrypt(iv_gen, ct, ctlen, tag, taglen);
+}
+#endif /* FIPS_MODE */
+
+int setup_tests(void)
+{
+    ADD_TEST(kat_test);
+#ifdef FIPS_MODE
+    ADD_TEST(ivgen_test);
+#endif /* FIPS_MODE */
+    return 1;
+}
index 5bf6fd0..4dd400f 100644 (file)
@@ -50,7 +50,7 @@ IF[{- !$disabled{tests} -}]
           time_offset_test pemtest ssl_cert_table_internal_test ciphername_test \
           servername_test ocspapitest rsa_mp_test fatalerrtest tls13ccstest \
           sysdefaulttest errtest gosttest \
-          context_internal_test
+          context_internal_test aesgcmtest
 
   SOURCE[versions]=versions.c
   INCLUDE[versions]=../include ../apps/include
@@ -570,6 +570,10 @@ IF[{- !$disabled{tests} -}]
   INCLUDE[gosttest]=../include ../apps/include ..
   DEPEND[gosttest]=../libcrypto ../libssl libtestutil.a
 
+  SOURCE[aesgcmtest]=aesgcmtest.c
+  INCLUDE[aesgcmtest]=../include ../apps/include ..
+  DEPEND[aesgcmtest]=../libcrypto libtestutil.a
+
   PROGRAMS{noinst}=context_internal_test
   SOURCE[context_internal_test]=context_internal_test.c
   INCLUDE[context_internal_test]=.. ../include ../apps/include
diff --git a/test/recipes/30-test_aesgcm.t b/test/recipes/30-test_aesgcm.t
new file mode 100644 (file)
index 0000000..f4862bf
--- /dev/null
@@ -0,0 +1,12 @@
+#! /usr/bin/env perl
+# Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
+#
+# Licensed under the Apache License 2.0 (the "License").  You may not use
+# this file except in compliance with the License.  You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
+
+use OpenSSL::Test::Simple;
+
+simple_test("test_aesgcm", "aesgcmtest", "aesgcm");