Re: [PATCH v2] crypto: Introduce SM4 symmetric cipher algorithm

[Yong Huang]

On Tue, Nov 28, 2023 at 11:57 PM Philippe Mathieu-Daudé <philmd@linaro.org> wrote:

Hi Hyman,

On 28/11/23 16:24, 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 for enabling this feature.
>
> 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                     | 23 ++++++++++++++++
>   meson_options.txt               |  2 ++
>   qapi/crypto.json                |  5 +++-
>   scripts/meson-buildoptions.sh   |  3 ++
>   tests/unit/test-crypto-cipher.c | 13 +++++++++
>   9 files changed, 119 insertions(+), 1 deletion(-)


> diff --git a/meson.build b/meson.build
> index ec01f8b138..256d3257bb 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()
> @@ -1514,6 +1515,26 @@ if not gnutls_crypto.found()
>         xts = 'private'
>       endif
>     endif
> +  if get_option('crypto_sm4').enabled()

We want to detect it by default (not only when explicitly enabled) ...

Ok, get it.

> +    if get_option('gcrypt').enabled()
> +      # SM4 ALG is available in libgcrypt >= 1.9
> +      crypto_sm4 = dependency('libgcrypt', version: '>=1.9',
> +                              method: 'config-tool',
> +                              required: get_option('gcrypt'))
> +      # SM4 ALG static compilation
> +      if crypto_sm4.found() and get_option('prefer_static')
> +        crypto_sm4 = declare_dependency(dependencies: [
> +          crypto_sm4,
> +          cc.find_library('gpg-error', required: true)],
> +          version: crypto_sm4.version())
> +      endif
> +    else
> +      # SM4 ALG is available in nettle >= 3.9
> +      crypto_sm4 = dependency('nettle', version: '>=3.9',
> +                              method: 'pkg-config',
> +                              required: get_option('nettle'))
> +    endif

... and if it was forced with --enable-crypto_sm4 AND not found,
display an error.

Ok.

IIUC your config you try to find the best effort implementation then
if not found, keep going silently.

> +  endif
>   endif


> diff --git a/scripts/meson-buildoptions.sh b/scripts/meson-buildoptions.sh
> index 680fa3f581..f189f34829 100644
> --- a/scripts/meson-buildoptions.sh
> +++ b/scripts/meson-buildoptions.sh
> @@ -106,6 +106,7 @@ meson_options_help() {
>     printf "%s\n" '  colo-proxy      colo-proxy support'
>     printf "%s\n" '  coreaudio       CoreAudio sound support'
>     printf "%s\n" '  crypto-afalg    Linux AF_ALG crypto backend driver'
> +  printf "%s\n" '  crypto-sm4      SM4 symmetric cipher algorithm support'
>     printf "%s\n" '  curl            CURL block device driver'
>     printf "%s\n" '  curses          curses UI'
>     printf "%s\n" '  dbus-display    -display dbus support'
> @@ -282,6 +283,8 @@ _meson_option_parse() {
>       --disable-coroutine-pool) printf "%s" -Dcoroutine_pool=false ;;
>       --enable-crypto-afalg) printf "%s" -Dcrypto_afalg=enabled ;;
>       --disable-crypto-afalg) printf "%s" -Dcrypto_afalg=disabled ;;
> +    --enable-crypto-sm4) printf "%s" -Dcrypto_sm4=enabled ;;
> +    --disable-crypto-sm4) printf "%s" -Dcrypto_sm4=disabled ;;
>       --enable-curl) printf "%s" -Dcurl=enabled ;;
>       --disable-curl) printf "%s" -Dcurl=disabled ;;
>       --enable-curses) printf "%s" -Dcurses=enabled ;;

--

Best regards