mirror of
https://github.com/vanhoefm/fragattacks.git
synced 2024-11-28 18:28:23 -05:00
EAP peer: Clear temporary message buffers before freeing
These buffers in TLS-based EAP methods might contain keys or password (e.g., when using TTLS-PAP or PEAP-GTC), so clear them explicitly to avoid leaving such material into heap memory unnecessarily. Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
This commit is contained in:
Jouni Malinen
Jouni Malinen
parent
8f99a3c26a
commit
789b48bb48
@ -250,8 +250,8 @@ static void eap_fast_deinit(struct eap_sm *sm, void *priv)
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os_memset(data->key_data, 0, EAP_FAST_KEY_LEN);
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os_memset(data->emsk, 0, EAP_EMSK_LEN);
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os_free(data->session_id);
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wpabuf_free(data->pending_phase2_req);
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wpabuf_free(data->pending_resp);
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wpabuf_clear_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_resp);
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os_free(data);
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}
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@ -486,7 +486,7 @@ static int eap_fast_phase2_request(struct eap_sm *sm,
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(config->pending_req_identity || config->pending_req_password ||
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config->pending_req_otp || config->pending_req_new_password ||
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config->pending_req_sim)) {
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wpabuf_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_phase2_req);
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data->pending_phase2_req = wpabuf_alloc_copy(hdr, len);
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} else if (*resp == NULL)
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return -1;
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@ -801,7 +801,7 @@ static struct wpabuf * eap_fast_process_crypto_binding(
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ret->methodState = METHOD_DONE;
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ret->decision = DECISION_FAIL;
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data->phase2_success = 0;
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wpabuf_free(resp);
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wpabuf_clear_free(resp);
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return NULL;
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}
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@ -815,7 +815,7 @@ static struct wpabuf * eap_fast_process_crypto_binding(
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} else {
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wpa_printf(MSG_ERROR, "EAP-FAST: Failed to derive "
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"Session-Id");
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wpabuf_free(resp);
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wpabuf_clear_free(resp);
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return NULL;
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}
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}
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@ -1150,7 +1150,7 @@ static int eap_fast_encrypt_response(struct eap_sm *sm,
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wpa_printf(MSG_INFO, "EAP-FAST: Failed to encrypt a Phase 2 "
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"frame");
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}
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wpabuf_free(resp);
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wpabuf_clear_free(resp);
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return 0;
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}
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@ -1328,14 +1328,14 @@ continue_req:
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wpa_printf(MSG_INFO, "EAP-FAST: Too short Phase 2 "
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"TLV frame (len=%lu)",
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(unsigned long) wpabuf_len(in_decrypted));
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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return -1;
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}
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res = eap_fast_process_decrypted(sm, data, ret, identifier,
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in_decrypted, out_data);
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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return res;
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}
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@ -1613,7 +1613,7 @@ static struct wpabuf * eap_fast_process(struct eap_sm *sm, void *priv,
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if (sm->waiting_ext_cert_check) {
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wpa_printf(MSG_DEBUG,
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"EAP-FAST: Waiting external server certificate validation");
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wpabuf_free(data->pending_resp);
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wpabuf_clear_free(data->pending_resp);
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data->pending_resp = resp;
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return NULL;
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}
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@ -1641,7 +1641,7 @@ static struct wpabuf * eap_fast_process(struct eap_sm *sm, void *priv,
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"EAP-FAST: Could not derive keys");
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ret->methodState = METHOD_DONE;
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ret->decision = DECISION_FAIL;
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wpabuf_free(resp);
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wpabuf_clear_free(resp);
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return NULL;
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}
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}
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@ -1650,7 +1650,7 @@ static struct wpabuf * eap_fast_process(struct eap_sm *sm, void *priv,
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/*
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* Application data included in the handshake message.
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*/
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wpabuf_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_phase2_req);
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data->pending_phase2_req = resp;
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resp = NULL;
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res = eap_fast_decrypt(sm, data, ret, id, &msg, &resp);
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@ -1658,7 +1658,7 @@ static struct wpabuf * eap_fast_process(struct eap_sm *sm, void *priv,
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}
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if (res == 1) {
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wpabuf_free(resp);
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wpabuf_clear_free(resp);
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return eap_peer_tls_build_ack(id, EAP_TYPE_FAST,
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data->fast_version);
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}
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@ -1684,9 +1684,9 @@ static void eap_fast_deinit_for_reauth(struct eap_sm *sm, void *priv)
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data->phase2_method->deinit_for_reauth(sm, data->phase2_priv);
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os_free(data->key_block_p);
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data->key_block_p = NULL;
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wpabuf_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_phase2_req);
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data->pending_phase2_req = NULL;
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wpabuf_free(data->pending_resp);
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wpabuf_clear_free(data->pending_resp);
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data->pending_resp = NULL;
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}
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@ -186,8 +186,8 @@ static void eap_peap_deinit(struct eap_sm *sm, void *priv)
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eap_peer_tls_ssl_deinit(sm, &data->ssl);
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eap_peap_free_key(data);
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os_free(data->session_id);
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wpabuf_free(data->pending_phase2_req);
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wpabuf_free(data->pending_resp);
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wpabuf_clear_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_resp);
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bin_clear_free(data, sizeof(*data));
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}
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@ -385,7 +385,7 @@ static struct wpabuf * eap_tlv_build_result(struct eap_sm *sm,
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wpabuf_put_be16(msg, status); /* Status */
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if (crypto_tlv_used && eap_tlv_add_cryptobinding(sm, data, msg)) {
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wpabuf_free(msg);
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wpabuf_clear_free(msg);
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return NULL;
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}
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@ -654,11 +654,11 @@ static int eap_peap_phase2_request(struct eap_sm *sm,
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if (*resp == NULL) {
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ret->methodState = METHOD_DONE;
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ret->decision = DECISION_FAIL;
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wpabuf_free(buf);
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wpabuf_clear_free(buf);
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return -1;
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}
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wpabuf_put_buf(*resp, buf);
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wpabuf_free(buf);
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wpabuf_clear_free(buf);
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break;
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}
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}
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@ -731,7 +731,7 @@ static int eap_peap_phase2_request(struct eap_sm *sm,
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(config->pending_req_identity || config->pending_req_password ||
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config->pending_req_otp || config->pending_req_new_password ||
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config->pending_req_sim)) {
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wpabuf_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_phase2_req);
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data->pending_phase2_req = wpabuf_alloc_copy(hdr, len);
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}
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@ -810,7 +810,7 @@ continue_req:
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struct wpabuf *nmsg = wpabuf_alloc(sizeof(struct eap_hdr) +
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wpabuf_len(in_decrypted));
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if (nmsg == NULL) {
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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return 0;
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}
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nhdr = wpabuf_put(nmsg, sizeof(*nhdr));
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@ -820,7 +820,7 @@ continue_req:
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nhdr->length = host_to_be16(sizeof(struct eap_hdr) +
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wpabuf_len(in_decrypted));
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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in_decrypted = nmsg;
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}
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@ -829,7 +829,7 @@ continue_req:
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wpa_printf(MSG_INFO, "EAP-PEAP: Too short Phase 2 "
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"EAP frame (len=%lu)",
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(unsigned long) wpabuf_len(in_decrypted));
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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return 0;
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}
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len = be_to_host16(hdr->length);
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@ -838,7 +838,7 @@ continue_req:
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"Phase 2 EAP frame (len=%lu hdr->length=%lu)",
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(unsigned long) wpabuf_len(in_decrypted),
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(unsigned long) len);
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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return 0;
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}
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if (len < wpabuf_len(in_decrypted)) {
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@ -855,7 +855,7 @@ continue_req:
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case EAP_CODE_REQUEST:
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if (eap_peap_phase2_request(sm, data, ret, in_decrypted,
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&resp)) {
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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wpa_printf(MSG_INFO, "EAP-PEAP: Phase2 Request "
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"processing failed");
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return 0;
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@ -875,7 +875,7 @@ continue_req:
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"completed successfully");
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ret->methodState = METHOD_DONE;
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ret->decision = DECISION_FAIL;
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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return 0;
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}
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wpa_printf(MSG_DEBUG, "EAP-PEAP: Version 1 - "
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@ -885,7 +885,7 @@ continue_req:
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ret->methodState = METHOD_DONE;
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data->phase2_success = 1;
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if (data->peap_outer_success == 2) {
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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wpa_printf(MSG_DEBUG, "EAP-PEAP: Use TLS ACK "
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"to finish authentication");
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return 1;
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@ -931,7 +931,7 @@ continue_req:
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break;
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}
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wpabuf_free(in_decrypted);
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wpabuf_clear_free(in_decrypted);
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if (resp) {
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int skip_change2 = 0;
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@ -958,7 +958,7 @@ continue_req:
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wpa_printf(MSG_INFO, "EAP-PEAP: Failed to encrypt "
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"a Phase 2 frame");
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}
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wpabuf_free(resp);
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wpabuf_clear_free(resp);
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}
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return 0;
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@ -1059,7 +1059,7 @@ static struct wpabuf * eap_peap_process(struct eap_sm *sm, void *priv,
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if (sm->waiting_ext_cert_check) {
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wpa_printf(MSG_DEBUG,
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"EAP-PEAP: Waiting external server certificate validation");
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wpabuf_free(data->pending_resp);
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wpabuf_clear_free(data->pending_resp);
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data->pending_resp = resp;
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return NULL;
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}
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@ -1140,7 +1140,7 @@ static struct wpabuf * eap_peap_process(struct eap_sm *sm, void *priv,
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/*
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* Application data included in the handshake message.
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*/
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wpabuf_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_phase2_req);
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data->pending_phase2_req = resp;
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resp = NULL;
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res = eap_peap_decrypt(sm, data, ret, req, &msg,
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@ -1153,7 +1153,7 @@ static struct wpabuf * eap_peap_process(struct eap_sm *sm, void *priv,
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}
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if (res == 1) {
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wpabuf_free(resp);
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wpabuf_clear_free(resp);
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return eap_peer_tls_build_ack(id, EAP_TYPE_PEAP,
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data->peap_version);
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}
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@ -1177,9 +1177,9 @@ static void eap_peap_deinit_for_reauth(struct eap_sm *sm, void *priv)
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if (data->phase2_priv && data->phase2_method &&
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data->phase2_method->deinit_for_reauth)
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data->phase2_method->deinit_for_reauth(sm, data->phase2_priv);
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wpabuf_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_phase2_req);
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data->pending_phase2_req = NULL;
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wpabuf_free(data->pending_resp);
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wpabuf_clear_free(data->pending_resp);
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data->pending_resp = NULL;
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data->crypto_binding_used = 0;
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}
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@ -196,8 +196,8 @@ static void eap_ttls_deinit(struct eap_sm *sm, void *priv)
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eap_peer_tls_ssl_deinit(sm, &data->ssl);
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eap_ttls_free_key(data);
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os_free(data->session_id);
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wpabuf_free(data->pending_phase2_req);
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wpabuf_free(data->pending_resp);
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wpabuf_clear_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_resp);
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os_free(data);
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}
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@ -248,7 +248,7 @@ static int eap_ttls_avp_encapsulate(struct wpabuf **resp, u32 avp_code,
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msg = wpabuf_alloc(sizeof(struct ttls_avp) + wpabuf_len(*resp) + 4);
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if (msg == NULL) {
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wpabuf_free(*resp);
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wpabuf_clear_free(*resp);
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*resp = NULL;
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return -1;
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}
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@ -258,7 +258,7 @@ static int eap_ttls_avp_encapsulate(struct wpabuf **resp, u32 avp_code,
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os_memcpy(pos, wpabuf_head(*resp), wpabuf_len(*resp));
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pos += wpabuf_len(*resp);
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AVP_PAD(avp, pos);
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wpabuf_free(*resp);
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wpabuf_clear_free(*resp);
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wpabuf_put(msg, pos - avp);
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*resp = msg;
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return 0;
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@ -510,7 +510,7 @@ static int eap_ttls_phase2_request_mschapv2(struct eap_sm *sm,
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challenge = eap_ttls_implicit_challenge(
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sm, data, EAP_TTLS_MSCHAPV2_CHALLENGE_LEN + 1);
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if (challenge == NULL) {
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wpabuf_free(msg);
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wpabuf_clear_free(msg);
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wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAPV2: Failed to derive "
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"implicit challenge");
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return -1;
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@ -529,7 +529,7 @@ static int eap_ttls_phase2_request_mschapv2(struct eap_sm *sm,
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*pos++ = 0; /* Flags */
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if (os_get_random(pos, EAP_TTLS_MSCHAPV2_CHALLENGE_LEN) < 0) {
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os_free(challenge);
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wpabuf_free(msg);
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wpabuf_clear_free(msg);
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wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAPV2: Failed to get "
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"random data for peer challenge");
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return -1;
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@ -543,7 +543,7 @@ static int eap_ttls_phase2_request_mschapv2(struct eap_sm *sm,
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peer_challenge, pos, data->auth_response,
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data->master_key)) {
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os_free(challenge);
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wpabuf_free(msg);
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wpabuf_clear_free(msg);
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wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAPV2: Failed to derive "
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"response");
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return -1;
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@ -604,7 +604,7 @@ static int eap_ttls_phase2_request_mschap(struct eap_sm *sm,
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challenge = eap_ttls_implicit_challenge(
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sm, data, EAP_TTLS_MSCHAP_CHALLENGE_LEN + 1);
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if (challenge == NULL) {
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wpabuf_free(msg);
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wpabuf_clear_free(msg);
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wpa_printf(MSG_ERROR, "EAP-TTLS/MSCHAP: Failed to derive "
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"implicit challenge");
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return -1;
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@ -628,7 +628,7 @@ static int eap_ttls_phase2_request_mschap(struct eap_sm *sm,
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if (challenge_response(challenge, password, pos)) {
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wpa_printf(MSG_ERROR,
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"EAP-TTLS/MSCHAP: Failed derive password hash");
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wpabuf_free(msg);
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wpabuf_clear_free(msg);
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os_free(challenge);
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return -1;
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}
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@ -641,7 +641,7 @@ static int eap_ttls_phase2_request_mschap(struct eap_sm *sm,
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pos)) {
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wpa_printf(MSG_ERROR,
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"EAP-TTLS/MSCHAP: Failed derive password");
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wpabuf_free(msg);
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wpabuf_clear_free(msg);
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os_free(challenge);
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return -1;
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}
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@ -760,7 +760,7 @@ static int eap_ttls_phase2_request_chap(struct eap_sm *sm,
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challenge = eap_ttls_implicit_challenge(
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sm, data, EAP_TTLS_CHAP_CHALLENGE_LEN + 1);
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if (challenge == NULL) {
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wpabuf_free(msg);
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wpabuf_clear_free(msg);
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wpa_printf(MSG_ERROR, "EAP-TTLS/CHAP: Failed to derive "
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"implicit challenge");
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return -1;
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@ -1073,10 +1073,10 @@ static int eap_ttls_encrypt_response(struct eap_sm *sm,
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resp, out_data)) {
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wpa_printf(MSG_INFO, "EAP-TTLS: Failed to encrypt a Phase 2 "
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"frame");
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wpabuf_free(resp);
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wpabuf_clear_free(resp);
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return -1;
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}
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wpabuf_free(resp);
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wpabuf_clear_free(resp);
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return 0;
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}
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@ -1297,7 +1297,7 @@ static int eap_ttls_process_decrypted(struct eap_sm *sm,
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config->pending_req_otp ||
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config->pending_req_new_password ||
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config->pending_req_sim) {
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wpabuf_free(data->pending_phase2_req);
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wpabuf_clear_free(data->pending_phase2_req);
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data->pending_phase2_req = wpabuf_dup(in_decrypted);
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}
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@ -1340,7 +1340,7 @@ static int eap_ttls_implicit_identity_request(struct eap_sm *sm,
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* processing when EAP request is re-processed after
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* user input.
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*/
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wpabuf_free(data->pending_phase2_req);
|
||||
wpabuf_clear_free(data->pending_phase2_req);
|
||||
data->pending_phase2_req = wpabuf_alloc(0);
|
||||
}
|
||||
|
||||
@ -1413,7 +1413,7 @@ static int eap_ttls_decrypt(struct eap_sm *sm, struct eap_ttls_data *data,
|
||||
in_decrypted = data->pending_phase2_req;
|
||||
data->pending_phase2_req = NULL;
|
||||
if (wpabuf_len(in_decrypted) == 0) {
|
||||
wpabuf_free(in_decrypted);
|
||||
wpabuf_clear_free(in_decrypted);
|
||||
return eap_ttls_implicit_identity_request(
|
||||
sm, data, ret, identifier, out_data);
|
||||
}
|
||||
@ -1449,7 +1449,7 @@ continue_req:
|
||||
&parse, in_decrypted, out_data);
|
||||
|
||||
done:
|
||||
wpabuf_free(in_decrypted);
|
||||
wpabuf_clear_free(in_decrypted);
|
||||
os_free(parse.eapdata);
|
||||
|
||||
if (retval < 0) {
|
||||
@ -1509,7 +1509,7 @@ static int eap_ttls_process_handshake(struct eap_sm *sm,
|
||||
if (sm->waiting_ext_cert_check) {
|
||||
wpa_printf(MSG_DEBUG,
|
||||
"EAP-TTLS: Waiting external server certificate validation");
|
||||
wpabuf_free(data->pending_resp);
|
||||
wpabuf_clear_free(data->pending_resp);
|
||||
data->pending_resp = *out_data;
|
||||
*out_data = NULL;
|
||||
return 0;
|
||||
@ -1543,7 +1543,7 @@ static int eap_ttls_process_handshake(struct eap_sm *sm,
|
||||
/*
|
||||
* Application data included in the handshake message.
|
||||
*/
|
||||
wpabuf_free(data->pending_phase2_req);
|
||||
wpabuf_clear_free(data->pending_phase2_req);
|
||||
data->pending_phase2_req = *out_data;
|
||||
*out_data = NULL;
|
||||
res = eap_ttls_decrypt(sm, data, ret, identifier, in_data,
|
||||
@ -1646,7 +1646,7 @@ static struct wpabuf * eap_ttls_process(struct eap_sm *sm, void *priv,
|
||||
/* FIX: what about res == -1? Could just move all error processing into
|
||||
* the other functions and get rid of this res==1 case here. */
|
||||
if (res == 1) {
|
||||
wpabuf_free(resp);
|
||||
wpabuf_clear_free(resp);
|
||||
return eap_peer_tls_build_ack(id, EAP_TYPE_TTLS,
|
||||
data->ttls_version);
|
||||
}
|
||||
@ -1669,9 +1669,9 @@ static void eap_ttls_deinit_for_reauth(struct eap_sm *sm, void *priv)
|
||||
if (data->phase2_priv && data->phase2_method &&
|
||||
data->phase2_method->deinit_for_reauth)
|
||||
data->phase2_method->deinit_for_reauth(sm, data->phase2_priv);
|
||||
wpabuf_free(data->pending_phase2_req);
|
||||
wpabuf_clear_free(data->pending_phase2_req);
|
||||
data->pending_phase2_req = NULL;
|
||||
wpabuf_free(data->pending_resp);
|
||||
wpabuf_clear_free(data->pending_resp);
|
||||
data->pending_resp = NULL;
|
||||
data->decision_succ = DECISION_FAIL;
|
||||
#ifdef EAP_TNC
|
||||
|
||||
Loading…
Reference in New Issue
Block a user