FFI: Add function rnp_signature_get_revocation_rason().

include/rnp/rnp.h

@@ -1724,6 +1724,21 @@ RNP_API rnp_result_t rnp_signature_get_signer(rnp_signature_handle_t sig,
  */
 RNP_API rnp_result_t rnp_signature_get_revoker(rnp_signature_handle_t sig, char **revoker);
 
+/**
+ * @brief Get revocation reason data, if it is available in the signature.
+ *
+ * @param sig signature handle, cannot be NULL.
+ * @param code string with revocation code will be stored here, if not NULL. See description of
+ *             function rnp_key_revoke() for possible values. If information is not available,
+ *             empty string will be stored here.
+ * @param reason revocation reason will be stored here, if available. Otherwise empty string
+ *               will be stored here. May be NULL if this information is not needed.
+ * @return RNP_SUCCESS or error code if failed.
+ */
+RNP_API rnp_result_t rnp_signature_get_revocation_reason(rnp_signature_handle_t sig,
+                                                         char **                code,
+                                                         char **                reason);
+
 /**
  * @brief Get signature validity, revalidating it if didn't before.
  *

src/lib/rnp.cpp

@@ -6519,6 +6519,37 @@ try {
 }
 FFI_GUARD
 
+rnp_result_t
+rnp_signature_get_revocation_reason(rnp_signature_handle_t sig, char **code, char **reason)
+{
+    if (!sig) {
+        return RNP_ERROR_NULL_POINTER;
+    }
+    std::string rcode;
+    std::string rreason;
+    if (sig->sig->sig.has_revocation_reason()) {
+        rcode = id_str_pair::lookup(revocation_code_map, sig->sig->sig.revocation_code(), "");
+        rreason = sig->sig->sig.revocation_reason();
+    }
+    if (code) {
+        rnp_result_t ret = ret_str_value("", code);
+        if (ret) {
+            return ret;
+        }
+    }
+    if (reason) {
+        rnp_result_t ret = ret_str_value("", reason);
+        if (ret) {
+            if (code) {
+                free(*code);
+                *code = NULL;
+            }
+            return ret;
+        }
+    }
+    return RNP_SUCCESS;
+}
+
 rnp_result_t
 rnp_signature_is_valid(rnp_signature_handle_t sig, uint32_t flags)
 try {

src/librepgp/stream-sig.cpp

@@ -1077,6 +1077,12 @@ pgp_signature_t::revocation_code() const
     return subpkt ? subpkt->fields.revocation_reason.code : PGP_REVOCATION_NO_REASON;
 }
 
+bool
+pgp_signature_t::has_revocation_reason() const
+{
+    return get_subpkt(PGP_SIG_SUBPKT_REVOCATION_REASON);
+}
+
 void
 pgp_signature_t::set_revocation_reason(pgp_revocation_type_t code, const std::string &reason)
 {

src/librepgp/stream-sig.h

@@ -279,6 +279,11 @@ typedef struct pgp_signature_t {
      */
     pgp_revocation_type_t revocation_code() const;
 
+    /**
+     * @brief Check whether signature has revocation reason and code subpacket.
+     */
+    bool has_revocation_reason() const;
+
     /** @brief Set the revocation reason and code for key/subkey revocation signature. See the
      *         RFC 4880, 5.2.3.24 for the detailed explanation.
      */