From 97fb2104fe2280a53875faed76f76140ccc7923f Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers@google.com>
Date: Thu, 18 Nov 2021 16:09:10 -0800
Subject: [PATCH] ANDROID: fips140: add support for injecting integrity error

The lab is required to test injecting an integrity error, so add a
module parameter fail_integrity_check=1 which does this.  This parameter
is only supported when CONFIG_CRYPTO_FIPS140_MOD_EVAL_TESTING=y.

Bug: 188620248
Change-Id: I1f3683837706dc1df2755ca5b6e88f21f7956135
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 crypto/fips140-eval-testing.c | 11 +++++++++++
 crypto/fips140-module.c       |  2 ++
 crypto/fips140-module.h       |  4 ++++
 3 files changed, 17 insertions(+)

diff --git a/crypto/fips140-eval-testing.c b/crypto/fips140-eval-testing.c
index fbcd4cc633d5..ef8edd0d1302 100644
--- a/crypto/fips140-eval-testing.c
+++ b/crypto/fips140-eval-testing.c
@@ -18,6 +18,10 @@
 static char *fips140_fail_selftest;
 module_param_named(fail_selftest, fips140_fail_selftest, charp, 0);
 
+/* This option allows deliberately failing the integrity check. */
+static bool fips140_fail_integrity_check;
+module_param_named(fail_integrity_check, fips140_fail_integrity_check, bool, 0);
+
 /* Inject a self-test failure (via corrupting the result) if requested. */
 void fips140_inject_selftest_failure(const char *impl, u8 *result)
 {
@@ -25,6 +29,13 @@ void fips140_inject_selftest_failure(const char *impl, u8 *result)
 		result[0] ^= 0xff;
 }
 
+/* Inject an integrity check failure (via corrupting the text) if requested. */
+void fips140_inject_integrity_failure(u8 *textcopy)
+{
+	if (fips140_fail_integrity_check)
+		textcopy[0] ^= 0xff;
+}
+
 bool fips140_eval_testing_init(void)
 {
 	return true;
diff --git a/crypto/fips140-module.c b/crypto/fips140-module.c
index 4ebcf12a8b2a..cd854fe28845 100644
--- a/crypto/fips140-module.c
+++ b/crypto/fips140-module.c
@@ -388,6 +388,8 @@ static bool __init check_fips140_module_hmac(void)
 				  offset_to_ptr(&fips140_rela_rodata.offset),
 				  fips140_rela_rodata.count);
 
+	fips140_inject_integrity_failure(textcopy);
+
 	tfm = crypto_alloc_shash("hmac(sha256)", 0, 0);
 	if (IS_ERR(tfm)) {
 		pr_err("failed to allocate hmac tfm (%ld)\n", PTR_ERR(tfm));
diff --git a/crypto/fips140-module.h b/crypto/fips140-module.h
index 92e2ff1ffbca..a2a63194eb64 100644
--- a/crypto/fips140-module.h
+++ b/crypto/fips140-module.h
@@ -23,11 +23,15 @@
 /* fips140-eval-testing.c */
 #ifdef CONFIG_CRYPTO_FIPS140_MOD_EVAL_TESTING
 void fips140_inject_selftest_failure(const char *impl, u8 *result);
+void fips140_inject_integrity_failure(u8 *textcopy);
 bool fips140_eval_testing_init(void);
 #else
 static inline void fips140_inject_selftest_failure(const char *impl, u8 *result)
 {
 }
+static inline void fips140_inject_integrity_failure(u8 *textcopy)
+{
+}
 static inline bool fips140_eval_testing_init(void)
 {
 	return true;