EBICS

The C ABI exposes EBICS as a backend handle opened with gln_open_ebics_backend. EBICS supports account/balance/transaction reads and SEPA transfer/direct-debit submissions through the shared backend operation surface.

For protocol background and current downloadable specifications, see the official EBICS specification page.

Open a Backend

gln_ebics_config_t config = {0};
gln_default_ebics_config(&config);
config.endpoint = "https://bank.example/ebicsweb";
config.host_id = "BANKHOST";
config.partner_id = "PARTNER01";
config.user_id = "USER01";
config.product_id = "MYPRODUCTID";

gln_backend_t* backend = NULL;
gln_error_t error = {0};
gln_default_error(&error);
gln_status_t status = gln_open_ebics_backend(
    &config,
    key_store,
    &backend,
    &error);

Close the backend with gln_close_backend. Release the key store only after every backend using it has been closed.

Service-Map Presets

gln_get_ebics_service_map_preset_json returns a caller-owned JSON service map for a named EBICS preset. The supported preset name is dkb; unsupported names return GLN_ERR_NOT_SUPPORTED and leave the output pointer as NULL.

Release a successful JSON output with gln_release_string.

Supported Operations

EBICS does not report support for TAN mode management, TAN media, continuation resume, instant transfer, holdings, standing orders, prepaid top-up, or info through the backend support table.

Setup and Key Lifecycle

The C ABI exposes the EBICS onboarding steps as explicit calls. It does not perform hidden reset or compatibility fallbacks.

The normal onboarding sequence is HEV, INI, HIA, HPB, verify pending bank keys, then confirm ready status. gln_download_ebics_bank_keys stages HPB keys as pending and returns GLN_ERR_FOLLOW_UP_REQUIRED; this is not a resumable TAN continuation. The envelope still has kind GLN_BACKEND_RESULT_KIND_EBICS_BANK_KEYS. Read gln_get_ebics_bank_keys_authentication_digest and gln_get_ebics_bank_keys_encryption_digest, compare both values against the bank-provided out-of-band source, then pass the expected values to gln_verify_pending_ebics_bank_keys.

gln_generate_ebics_ini_brief and gln_generate_ebics_hia_brief return caller-owned text buffers through out_brief_text. Release successful outputs with gln_release_string.

gln_reset_ebics_client_keys clears local subscriber key pairs and returns the new key status. gln_reset_ebics_bank_keys clears both trusted and pending bank keys and returns the new key status. After a bank-key reset, operational EBICS calls cannot verify bank responses or encrypt uploads until HPB stages fresh bank keys and gln_verify_pending_ebics_bank_keys promotes them. Do not treat bank-key reset as an automatic fallback for verification failures.

Provider Status Rows

EBICS success results for submissions can expose provider status through gln_provider_status_t rows.

For EBICS rows, code_or_null carries the business code when a business code is present and the technical code otherwise. subcode_or_null carries the technical code when a business code is present.

Result Semantics

EBICS has no VoP layer in this ABI. Transfer VoP accessors return NULL on EBICS submission handles.

Example: Submit a Transfer

gln_submit_transfer_request_t request = {0};
gln_default_submit_transfer_request(&request);
request.source_iban = "DE02120300000000202051";
request.source_bic = "BYLADEM1001";
request.source_name = "Example GmbH";
request.recipient_iban = "DE89370400440532013000";
request.recipient_bic = "COBADEFFXXX";
request.recipient_name = "Supplier GmbH";
request.amount = "125.40";
request.purpose = "Invoice 2026-05";

gln_backend_result_t* result = NULL;
if (gln_submit_transfer(backend, &request, &result) == GLN_OK &&
    gln_get_backend_result_outcome(result) == GLN_BACKEND_OUTCOME_SUCCESS) {
    const gln_transfer_submission_t* submission =
        gln_get_backend_result_transfer_submission(result);
    const char* order_id = gln_get_transfer_submission_id(submission);
    (void)order_id;
}
gln_destroy_backend_result(result);

Related Pages

• Backend results
• Key store
• Transfers
• Direct debits