Re: [PATCH v5 10/29] image: Use Kconfig to enable FIT_RSASSA_PSS on host

Alex G.
2021-10-05T18:32:28Z

On 9/25/21 8:43 PM, Simon Glass wrote:
> Add a host Kconfig for FIT_RSASSA_PSS. With this we can use
> CONFIG_IS_ENABLED(FIT_RSASSA_PSS) directly in the host build, so drop the
> forcing of this in the image.h header.
>
> Drop the #ifdef around padding_pss_verify() too since it is not needed.
> Use the compiler to check the config where possible, instead of the
> preprocessor.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>

Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>

> ---
>
> Changes in v5:
> - Avoid preprocessor in a few more places
> - Use TOOLS_ instead of HOST_
>
> include/image.h | 3 ---
> include/u-boot/rsa.h | 2 --
> lib/rsa/rsa-sign.c | 5 ++---
> lib/rsa/rsa-verify.c | 16 +++-------------
> tools/Kconfig | 5 +++++
> 5 files changed, 10 insertions(+), 21 deletions(-)

Now that's what I'm talking about! deletions > insertions
>
> diff --git a/include/image.h b/include/image.h
> index 6efbef06e64..dc872ef5b24 100644
> --- a/include/image.h
> +++ b/include/image.h
> @@ -27,9 +27,6 @@ struct fdt_region;
> #include <sys/types.h>
> #include <linux/kconfig.h>
>
> -/* new uImage format support enabled on host */
> -#define CONFIG_FIT_RSASSA_PSS 1
> -
> #define IMAGE_ENABLE_IGNORE 0
> #define IMAGE_INDENT_STRING ""
>
> diff --git a/include/u-boot/rsa.h b/include/u-boot/rsa.h
> index 89a9c4caa0a..7556aa5b4b7 100644
> --- a/include/u-boot/rsa.h
> +++ b/include/u-boot/rsa.h
> @@ -103,11 +103,9 @@ int padding_pkcs_15_verify(struct image_sign_info *info,
> uint8_t *msg, int msg_len,
> const uint8_t *hash, int hash_len);
>
> -#ifdef CONFIG_FIT_RSASSA_PSS
> int padding_pss_verify(struct image_sign_info *info,
> uint8_t *msg, int msg_len,
> const uint8_t *hash, int hash_len);
> -#endif /* CONFIG_FIT_RSASSA_PSS */
>
> #define RSA_DEFAULT_PADDING_NAME "pkcs-1.5"
>
> diff --git a/lib/rsa/rsa-sign.c b/lib/rsa/rsa-sign.c
> index c27a784c429..0579e5294ee 100644
> --- a/lib/rsa/rsa-sign.c
> +++ b/lib/rsa/rsa-sign.c
> @@ -401,15 +401,14 @@ static int rsa_sign_with_key(EVP_PKEY *pkey, struct padding_algo *padding_algo,
> goto err_sign;
> }
>
> -#ifdef CONFIG_FIT_RSASSA_PSS
> - if (padding_algo && !strcmp(padding_algo->name, "pss")) {
> + if (CONFIG_IS_ENABLED(FIT_RSASSA_PSS) && padding_algo &&
> + !strcmp(padding_algo->name, "pss")) {
> if (EVP_PKEY_CTX_set_rsa_padding(ckey,
> RSA_PKCS1_PSS_PADDING) <= 0) {
> ret = rsa_err("Signer padding setup failed");
> goto err_sign;
> }
> }
> -#endif /* CONFIG_FIT_RSASSA_PSS */
>
> for (i = 0; i < region_count; i++) {
> if (!EVP_DigestSignUpdate(context, region[i].data,
> diff --git a/lib/rsa/rsa-verify.c b/lib/rsa/rsa-verify.c
> index ad6d33d043a..9e522d210d7 100644
> --- a/lib/rsa/rsa-verify.c
> +++ b/lib/rsa/rsa-verify.c
> @@ -102,7 +102,6 @@ U_BOOT_PADDING_ALGO(pkcs_15) = {
> };
> #endif
>
> -#ifdef CONFIG_FIT_RSASSA_PSS
> static void u32_i2osp(uint32_t val, uint8_t *buf)
> {
> buf[0] = (uint8_t)((val >> 24) & 0xff);
> @@ -311,9 +310,6 @@ U_BOOT_PADDING_ALGO(pss) = {
> };
> #endif
>
> -#endif
> -
> -#if CONFIG_IS_ENABLED(FIT_SIGNATURE) || CONFIG_IS_ENABLED(RSA_VERIFY_WITH_PKEY)
> /**
> * rsa_verify_key() - Verify a signature against some data using RSA Key
> *
> @@ -385,9 +381,7 @@ static int rsa_verify_key(struct image_sign_info *info,
>
> return 0;
> }
> -#endif
>
> -#if CONFIG_IS_ENABLED(RSA_VERIFY_WITH_PKEY)
> /**
> * rsa_verify_with_pkey() - Verify a signature against some data using
> * only modulus and exponent as RSA key properties.
> @@ -408,6 +402,9 @@ int rsa_verify_with_pkey(struct image_sign_info *info,
> struct key_prop *prop;
> int ret;
>
> + if (!CONFIG_IS_ENABLED(RSA_VERIFY_WITH_PKEY))
> + return -EACCES;
> +
> /* Public key is self-described to fill key_prop */
> ret = rsa_gen_key_prop(info->key, info->keylen, &prop);
> if (ret) {
> @@ -422,13 +419,6 @@ int rsa_verify_with_pkey(struct image_sign_info *info,
>
> return ret;
> }
> -#else
> -int rsa_verify_with_pkey(struct image_sign_info *info,
> - const void *hash, uint8_t *sig, uint sig_len)
> -{
> - return -EACCES;
> -}
> -#endif
>
> #if CONFIG_IS_ENABLED(FIT_SIGNATURE)
> /**
> diff --git a/tools/Kconfig b/tools/Kconfig
> index 9d1c0efd40c..8685c800f93 100644
> --- a/tools/Kconfig
> +++ b/tools/Kconfig
> @@ -35,6 +35,11 @@ config TOOLS_FIT_PRINT
> help
> Print the content of the FIT verbosely in the tools builds
>
> +config TOOLS_FIT_RSASSA_PSS
> + def_bool y
> + help
> + Support the rsassa-pss signature scheme in the tools builds

If we're going to have these TOOLS_ configs always on, what's the point
in adding a help text?

> +
> config TOOLS_FIT_SIGNATURE
> def_bool y
> help
>