Re: [PATCH v3] crypto: Introduce SM4 symmetric cipher algorithm

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 29/11/23 16:17, Hyman Huang wrote:
> Introduce the SM4 cipher algorithms (OSCCA GB/T 32907-2016).
> 
> SM4 (GBT.32907-2016) is a cryptographic standard issued by the
> Organization of State Commercial Administration of China (OSCCA)
> as an authorized cryptographic algorithms for the use within China.
> 
> Use the crypto-sm4 meson build option to explicitly control the
> feature, which would be detected by default.
> 
> Signed-off-by: Hyman Huang <yong.huang@smartx.com>
> ---
>   crypto/block-luks.c             | 11 ++++++++
>   crypto/cipher-gcrypt.c.inc      |  8 ++++++
>   crypto/cipher-nettle.c.inc      | 49 +++++++++++++++++++++++++++++++++
>   crypto/cipher.c                 |  6 ++++
>   meson.build                     | 42 ++++++++++++++++++++++++++++
>   meson_options.txt               |  2 ++
>   qapi/crypto.json                |  5 +++-
>   scripts/meson-buildoptions.sh   |  3 ++
>   tests/unit/test-crypto-cipher.c | 13 +++++++++
>   9 files changed, 138 insertions(+), 1 deletion(-)


> diff --git a/meson.build b/meson.build
> index ec01f8b138..765f9c9f50 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -1480,6 +1480,7 @@ endif
>   gcrypt = not_found
>   nettle = not_found
>   hogweed = not_found
> +crypto_sm4 = not_found
>   xts = 'none'
>   
>   if get_option('nettle').enabled() and get_option('gcrypt').enabled()
> @@ -1505,6 +1506,28 @@ if not gnutls_crypto.found()
>            cc.find_library('gpg-error', required: true)],
>           version: gcrypt.version())
>       endif
> +    crypto_sm4 = gcrypt
> +    # SM4 ALG is available in libgcrypt >= 1.9
> +    if gcrypt.found() and not cc.links('''
> +      #include <gcrypt.h>
> +      int main(void) {
> +        gcry_cipher_hd_t handler;
> +        gcry_cipher_open(&handler, GCRY_CIPHER_SM4, GCRY_CIPHER_MODE_ECB, 0);
> +        return 0;
> +      }''', dependencies: gcrypt)
> +      crypto_sm4 = not_found
> +      if get_option('crypto_sm4').enabled()
> +        error('could not link sm4')

'could not link libsm4'? Up to the maintainer.

> +      else
> +        warning('could not link sm4, disabling')
> +      endif
> +    endif
> +    if crypto_sm4.found() and get_option('prefer_static')
> +      crypto_sm4 = declare_dependency(dependencies: [
> +        gcrypt,
> +        cc.find_library('gpg-error', required: true)],
> +        version: gcrypt.version())
> +    endif
>     endif
>     if (not get_option('nettle').auto() or have_system) and not gcrypt.found()
>       nettle = dependency('nettle', version: '>=3.4',
> @@ -1513,6 +1536,23 @@ if not gnutls_crypto.found()
>       if nettle.found() and not cc.has_header('nettle/xts.h', dependencies: nettle)
>         xts = 'private'
>       endif
> +    crypto_sm4 = nettle
> +    # SM4 ALG is available in nettle >= 3.9
> +    if nettle.found() and not cc.links('''
> +      #include <nettle/sm4.h>
> +      int main(void) {
> +        struct sm4_ctx ctx;
> +        unsigned char key[16] = {0};
> +        sm4_set_encrypt_key(&ctx, key);
> +        return 0;
> +      }''', dependencies: nettle)
> +      crypto_sm4 = not_found
> +      if get_option('crypto_sm4').enabled()
> +        error('could not link sm4')

Ditto, otherwise:
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

> +      else
> +        warning('could not link sm4, disabling')
> +      endif
> +    endif
>     endif
>   endif