crypto: Introduce SM4 symmetric cipher algorithm

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.

Detect the SM4 cipher algorithms and enable the feature silently
if it is available.

Signed-off-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/meson.build b/meson.build
index 74d3aa0b12..c1dc83e4c0 100644
--- a/meson.build
+++ b/meson.build
@@ -1633,6 +1633,7 @@ 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()
@@ -1658,6 +1659,17 @@ 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
+    endif
   endif
   if (not get_option('nettle').auto() or have_system) and not gcrypt.found()
     nettle = dependency('nettle', version: '>=3.4',
@@ -1666,6 +1678,18 @@ 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
+    endif
   endif
 endif
 
@@ -2267,6 +2291,7 @@ config_host_data.set('CONFIG_GNUTLS_CRYPTO', gnutls_crypto.found())
 config_host_data.set('CONFIG_TASN1', tasn1.found())
 config_host_data.set('CONFIG_GCRYPT', gcrypt.found())
 config_host_data.set('CONFIG_NETTLE', nettle.found())
+config_host_data.set('CONFIG_CRYPTO_SM4', crypto_sm4.found())
 config_host_data.set('CONFIG_HOGWEED', hogweed.found())
 config_host_data.set('CONFIG_QEMU_PRIVATE_XTS', xts == 'private')
 config_host_data.set('CONFIG_MALLOC_TRIM', has_malloc_trim)
@@ -4306,6 +4331,7 @@ summary_info += {'nettle':            nettle}
 if nettle.found()
    summary_info += {'  XTS':             xts != 'private'}
 endif
+summary_info += {'SM4 ALG support':   crypto_sm4}
 summary_info += {'AF_ALG support':    have_afalg}
 summary_info += {'rng-none':          get_option('rng_none')}
 summary_info += {'Linux keyring':     have_keyring}