Re: [PATCH v6 1/5] IMA: remove the dependency on CRYPTO_MD5
From: Mimi Zohar <zohar@linux.ibm.com>
Date: 2021-08-09 20:59:22
On Wed, 2021-08-04 at 09:20 +0000, THOBY Simon wrote:
quoted hunk ↗ jump to hunk
MD5 is a weak digest algorithm that shouldn't be used for cryptographic operation. It hinders the efficiency of a patch set that aims to limit the digests allowed for the extended file attribute namely security.ima. MD5 is no longer a requirement for IMA, nor should it be used there. Remove the CRYPTO_MD5 dependency for IMA. Signed-off-by: Simon Thoby <redacted> --- security/integrity/ima/Kconfig | 1 - security/integrity/ima/ima_main.c | 3 ++- 2 files changed, 2 insertions(+), 2 deletions(-)diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig index d0ceada99243..f3a9cc201c8c 100644 --- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig@@ -6,7 +6,6 @@ config IMA select SECURITYFS select CRYPTO select CRYPTO_HMAC - select CRYPTO_MD5 select CRYPTO_SHA1 select CRYPTO_HASH_INFO select TCG_TPM if HAS_IOMEM && !UMLdiff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 1cba6beb5a60..b70ee0125168 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c@@ -53,7 +53,8 @@ static int __init hash_setup(char *str) if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) { if (strncmp(str, "sha1", 4) == 0) { ima_hash_algo = HASH_ALGO_SHA1; - } else if (strncmp(str, "md5", 3) == 0) { + } else if (IS_ENABLED(CONFIG_CRYPTO_MD5) + && strncmp(str, "md5", 3) == 0) { ima_hash_algo = HASH_ALGO_MD5; } else { pr_err("invalid hash algorithm \"%s\" for template \"%s\"",
FYI, with the non "ima" template formats and MD5 is not configured, it fails with the following messages: ima: Can not allocate md5 (reason: -2) ima: Allocating md5 failed, going to use default hash algorithm sha256 thanks, Mimi