gpgsm: New option --require-compliance

* sm/gpgsm.c (oRequireCompliance): New.
(opts): Add --require-compliance.
(main): Set option.
* sm/gpgsm.h (opt): Add field require_compliance.
(gpgsm_errors_seen): Declare.
* sm/verify.c (gpgsm_verify): Emit error if non de-vs compliant.
* sm/encrypt.c (gpgsm_encrypt): Ditto.
* sm/decrypt.c (gpgsm_decrypt): Ditto.

doc/gpgsm.texi

@@ -676,6 +676,17 @@ This option adjusts the compliance mode "de-vs" for stricter key size
 requirements.  For example, a value of 3000 turns rsa2048 and dsa2048
 keys into non-VS-NfD compliant keys.
 
+@item --require-compliance
+@opindex require-compliance
+To check that data has been encrypted according to the rules of the
+current compliance mode, a gpgsm user needs to evaluate the status
+lines.  This is allows frontends to handle compliance check in a more
+flexible way.  However, for scripted use the required evaluation of
+the status-line requires quite some effort; this option can be used
+instead to make sure that the gpgsm process exits with a failure if
+the compliance rules are not fulfilled.  Note that this option has
+currently an effect only in "de-vs" mode.
+
 @item --ignore-cert-with-oid @var{oid}
 @opindex ignore-cert-with-oid
 Add @var{oid} to the list of OIDs to be checked while reading

sm/decrypt.c

@@ -1029,7 +1029,13 @@ gpgsm_decrypt (ctrl_t ctrl, int in_fd, estream_t out_fp)
                           && gnupg_gcrypt_is_compliant (CO_DE_VS))
                         gpgsm_status (ctrl, STATUS_DECRYPTION_COMPLIANCE_MODE,
                                       gnupg_status_compliance_flag (CO_DE_VS));
-
+                      else if (opt.require_compliance
+                               && opt.compliance == CO_DE_VS)
+                        {
+                          log_error (_("operation forced to fail due to"
+                                       " unfulfilled compliance rules\n"));
+                          gpgsm_errors_seen = 1;
+                        }
                     }
                   audit_log_ok (ctrl->audit, AUDIT_RECP_RESULT, rc);
                 }

sm/encrypt.c

@@ -535,6 +535,15 @@ gpgsm_encrypt (ctrl_t ctrl, certlist_t recplist, int data_fd, estream_t out_fp)
   if (compliant && gnupg_gcrypt_is_compliant (CO_DE_VS))
     gpgsm_status (ctrl, STATUS_ENCRYPTION_COMPLIANCE_MODE,
                   gnupg_status_compliance_flag (CO_DE_VS));
+  else if (opt.require_compliance
+           && opt.compliance == CO_DE_VS)
+    {
+      log_error (_("operation forced to fail due to"
+                   " unfulfilled compliance rules\n"));
+      gpgsm_errors_seen = 1;
+      rc = gpg_error (GPG_ERR_FORBIDDEN);
+      goto leave;
+    }
 
   /* Main control loop for encryption. */
   recpno = 0;

sm/gpgsm.c

@@ -199,6 +199,7 @@ enum cmd_and_opt_values {
   oNoCommonCertsImport,
   oIgnoreCertExtension,
   oIgnoreCertWithOID,
+  oRequireCompliance,
   oNoAutostart
  };
 
@@ -289,6 +290,7 @@ static ARGPARSE_OPTS opts[] = {
   ARGPARSE_s_s (oPolicyFile, "policy-file",
                 N_("|FILE|take policy information from FILE")),
   ARGPARSE_s_s (oCompliance, "compliance",   "@"),
+  ARGPARSE_p_u (oMinRSALength, "min-rsa-length", "@"),
   ARGPARSE_s_n (oNoCommonCertsImport, "no-common-certs-import", "@"),
   ARGPARSE_s_s (oIgnoreCertExtension, "ignore-cert-extension", "@"),
   ARGPARSE_s_s (oIgnoreCertWithOID, "ignore-cert-with-oid", "@"),
@@ -387,7 +389,7 @@ static ARGPARSE_OPTS opts[] = {
   ARGPARSE_s_s (oDisablePubkeyAlgo,  "disable-pubkey-algo", "@"),
   ARGPARSE_s_n (oIgnoreTimeConflict, "ignore-time-conflict", "@"),
   ARGPARSE_s_n (oNoRandomSeedFile,  "no-random-seed-file", "@"),
-  ARGPARSE_p_u (oMinRSALength, "min-rsa-length", "@"),
+  ARGPARSE_s_n (oRequireCompliance, "require-compliance", "@"),
 
 
   ARGPARSE_header (NULL, N_("Options for unattended use")),
@@ -421,7 +423,6 @@ static ARGPARSE_OPTS opts[] = {
   ARGPARSE_s_s (oLCmessages, "lc-messages", "@"),
   ARGPARSE_s_s (oXauthority, "xauthority", "@"),
 
-
   ARGPARSE_header (NULL, ""),  /* Stop the header group.  */
 
 
@@ -1410,6 +1411,8 @@ main ( int argc, char **argv)
 
         case oMinRSALength: opt.min_rsa_length = pargs.r.ret_ulong; break;
 
+        case oRequireCompliance: opt.require_compliance = 1;  break;
+
         default:
           if (configname)
             pargs.err = ARGPARSE_PRINT_WARNING;

sm/gpgsm.h

@@ -143,7 +143,13 @@ struct
    * sunch an OID during --learn-card.  */
   strlist_t ignore_cert_with_oid;
 
+  /* The current compliance mode.  */
   enum gnupg_compliance_mode compliance;
+
+  /* Fail if an operation can't be done in the requested compliance
+   * mode.  */
+  int require_compliance;
+
 } opt;
 
 /* Debug values and macros.  */
@@ -234,6 +240,8 @@ struct rootca_flags_s
 
 
 /*-- gpgsm.c --*/
+extern int gpgsm_errors_seen;
+
 void gpgsm_exit (int rc);
 void gpgsm_init_default_ctrl (struct server_control_s *ctrl);
 int  gpgsm_parse_validation_model (const char *model);

sm/verify.c

@@ -516,6 +516,13 @@ gpgsm_verify (ctrl_t ctrl, int in_fd, int data_fd, estream_t out_fp)
           && gnupg_digest_is_compliant (CO_DE_VS, sigval_hash_algo))
         gpgsm_status (ctrl, STATUS_VERIFICATION_COMPLIANCE_MODE,
                       gnupg_status_compliance_flag (CO_DE_VS));
+      else if (opt.require_compliance
+               && opt.compliance == CO_DE_VS)
+        {
+          log_error (_("operation forced to fail due to"
+                       " unfulfilled compliance rules\n"));
+          gpgsm_errors_seen = 1;
+        }
 
 
       /* Now we can check the signature.  */