diff --git a/src/common/dpp.c b/src/common/dpp.c index 154722b12..ae5fbd384 100644 --- a/src/common/dpp.c +++ b/src/common/dpp.c @@ -3107,6 +3107,77 @@ fail: } +static int dpp_auth_conf_rx_failure(struct dpp_authentication *auth, + const u8 *hdr, + const u8 *attr_start, size_t attr_len, + const u8 *wrapped_data, + u16 wrapped_data_len, + enum dpp_status_error status) +{ + const u8 *addr[2]; + size_t len[2]; + u8 *unwrapped = NULL; + size_t unwrapped_len = 0; + const u8 *r_nonce; + u16 r_nonce_len; + + /* Authentication Confirm failure cases are expected to include + * {R-nonce}k2 in the Wrapped Data attribute. */ + + addr[0] = hdr; + len[0] = DPP_HDR_LEN; + addr[1] = attr_start; + len[1] = attr_len; + wpa_hexdump(MSG_DEBUG, "DDP: AES-SIV AD[0]", addr[0], len[0]); + wpa_hexdump(MSG_DEBUG, "DDP: AES-SIV AD[1]", addr[1], len[1]); + wpa_hexdump(MSG_DEBUG, "DPP: AES-SIV ciphertext", + wrapped_data, wrapped_data_len); + unwrapped_len = wrapped_data_len - AES_BLOCK_SIZE; + unwrapped = os_malloc(unwrapped_len); + if (!unwrapped) { + dpp_auth_fail(auth, "Authentication failed"); + goto fail; + } + if (aes_siv_decrypt(auth->k2, auth->curve->hash_len, + wrapped_data, wrapped_data_len, + 2, addr, len, unwrapped) < 0) { + dpp_auth_fail(auth, "AES-SIV decryption failed"); + goto fail; + } + wpa_hexdump(MSG_DEBUG, "DPP: AES-SIV cleartext", + unwrapped, unwrapped_len); + + if (dpp_check_attrs(unwrapped, unwrapped_len) < 0) { + dpp_auth_fail(auth, "Invalid attribute in unwrapped data"); + goto fail; + } + + r_nonce = dpp_get_attr(unwrapped, unwrapped_len, DPP_ATTR_R_NONCE, + &r_nonce_len); + if (!r_nonce || r_nonce_len != auth->curve->nonce_len) { + dpp_auth_fail(auth, "DPP: Missing or invalid R-nonce"); + goto fail; + } + if (os_memcmp(r_nonce, auth->r_nonce, r_nonce_len) != 0) { + wpa_hexdump(MSG_DEBUG, "DPP: Received R-nonce", + r_nonce, r_nonce_len); + wpa_hexdump(MSG_DEBUG, "DPP: Expected R-nonce", + auth->r_nonce, r_nonce_len); + dpp_auth_fail(auth, "R-nonce mismatch"); + goto fail; + } + + if (status == DPP_STATUS_NOT_COMPATIBLE) + dpp_auth_fail(auth, "Peer reported incompatible R-capab role"); + else if (status == DPP_STATUS_AUTH_FAILURE) + dpp_auth_fail(auth, "Peer reported authentication failure)"); + +fail: + bin_clear_free(unwrapped, unwrapped_len); + return -1; +} + + int dpp_auth_conf_rx(struct dpp_authentication *auth, const u8 *hdr, const u8 *attr_start, size_t attr_len) { @@ -3186,6 +3257,12 @@ int dpp_auth_conf_rx(struct dpp_authentication *auth, const u8 *hdr, return -1; } wpa_printf(MSG_DEBUG, "DPP: Status %u", status[0]); + if (status[0] == DPP_STATUS_NOT_COMPATIBLE || + status[0] == DPP_STATUS_AUTH_FAILURE) + return dpp_auth_conf_rx_failure(auth, hdr, attr_start, + attr_len, wrapped_data, + wrapped_data_len, status[0]); + if (status[0] != DPP_STATUS_OK) { dpp_auth_fail(auth, "Authentication failed"); return -1;