Make exceptions easier to translate to error codes

Avoid throwing base Botan::Exception type, as it is difficult to
determine what the error is in that case.

Add Exception::error_code and Exception::error_type which allows
(for error code) more information about the error and (for error type)
allows knowing the error type without requiring a sequence of catches.

See GH #1742

1 files changed, 5 insertions, 1 deletions

diff --git a/src/lib/tls/tls_exceptn.h b/src/lib/tls/tls_exceptn.h
index 572ff1885..e7d8c1963 100644
--- a/src/lib/tls/tls_exceptn.h
+++ b/src/lib/tls/tls_exceptn.h
@@ -16,7 +16,7 @@ namespace Botan {
 namespace TLS {
 
 /**
-* Exception Base Class
+* TLS Exception Base Class
 */
 class BOTAN_PUBLIC_API(2,0) TLS_Exception : public Exception
    {
@@ -27,6 +27,10 @@ class BOTAN_PUBLIC_API(2,0) TLS_Exception : public Exception
                     const std::string& err_msg = "Unknown error") :
          Exception(err_msg), m_alert_type(type) {}
 
+      int error_code() const noexcept override { return static_cast<int>(m_alert_type); }
+
+      ErrorType error_type() const noexcept override { return ErrorType::TLSError; }
+
    private:
       Alert::Type m_alert_type;
    };