/* * PASN initiator processing * * Copyright (C) 2019, Intel Corporation * Copyright (C) 2022, Qualcomm Innovation Center, Inc. * * This software may be distributed under the terms of the BSD license. * See README for more details. */ #include "utils/includes.h" #include "utils/common.h" #include "common/wpa_common.h" #include "common/sae.h" #include "common/ieee802_11_common.h" #include "common/ieee802_11_defs.h" #include "common/dragonfly.h" #include "crypto/sha384.h" #include "crypto/crypto.h" #include "crypto/random.h" #include "eap_common/eap_defs.h" #include "eapol_supp/eapol_supp_sm.h" #include "rsn_supp/wpa.h" #include "rsn_supp/pmksa_cache.h" #include "pasn_common.h" void pasn_set_initiator_pmksa(struct pasn_data *pasn, struct rsn_pmksa_cache *pmksa) { if (pasn) pasn->pmksa = pmksa; } #ifdef CONFIG_SAE static struct wpabuf * wpas_pasn_wd_sae_commit(struct pasn_data *pasn) { struct wpabuf *buf = NULL; int ret; ret = sae_set_group(&pasn->sae, pasn->group); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed to set SAE group"); return NULL; } ret = sae_prepare_commit_pt(&pasn->sae, pasn->pt, pasn->own_addr, pasn->peer_addr, NULL, NULL); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed to prepare SAE commit"); return NULL; } /* Need to add the entire Authentication frame body */ buf = wpabuf_alloc(6 + SAE_COMMIT_MAX_LEN); if (!buf) { wpa_printf(MSG_DEBUG, "PASN: Failed to allocate SAE buffer"); return NULL; } wpabuf_put_le16(buf, WLAN_AUTH_SAE); wpabuf_put_le16(buf, 1); wpabuf_put_le16(buf, WLAN_STATUS_SAE_HASH_TO_ELEMENT); sae_write_commit(&pasn->sae, buf, NULL, 0); pasn->sae.state = SAE_COMMITTED; return buf; } static int wpas_pasn_wd_sae_rx(struct pasn_data *pasn, struct wpabuf *wd) { const u8 *data; size_t buf_len; u16 len, res, alg, seq, status; int groups[] = { pasn->group, 0 }; int ret; if (!wd) return -1; data = wpabuf_head_u8(wd); buf_len = wpabuf_len(wd); /* first handle the commit message */ if (buf_len < 2) { wpa_printf(MSG_DEBUG, "PASN: SAE buffer too short (commit)"); return -1; } len = WPA_GET_LE16(data); if (len < 6 || buf_len - 2 < len) { wpa_printf(MSG_DEBUG, "PASN: SAE buffer too short for commit"); return -1; } buf_len -= 2; data += 2; alg = WPA_GET_LE16(data); seq = WPA_GET_LE16(data + 2); status = WPA_GET_LE16(data + 4); wpa_printf(MSG_DEBUG, "PASN: SAE: commit: alg=%u, seq=%u, status=%u", alg, seq, status); if (alg != WLAN_AUTH_SAE || seq != 1 || status != WLAN_STATUS_SAE_HASH_TO_ELEMENT) { wpa_printf(MSG_DEBUG, "PASN: SAE: dropping peer commit"); return -1; } res = sae_parse_commit(&pasn->sae, data + 6, len - 6, NULL, 0, groups, 1, NULL); if (res != WLAN_STATUS_SUCCESS) { wpa_printf(MSG_DEBUG, "PASN: SAE failed parsing commit"); return -1; } /* Process the commit message and derive the PMK */ ret = sae_process_commit(&pasn->sae); if (ret) { wpa_printf(MSG_DEBUG, "SAE: Failed to process peer commit"); return -1; } buf_len -= len; data += len; /* Handle the confirm message */ if (buf_len < 2) { wpa_printf(MSG_DEBUG, "PASN: SAE buffer too short (confirm)"); return -1; } len = WPA_GET_LE16(data); if (len < 6 || buf_len - 2 < len) { wpa_printf(MSG_DEBUG, "PASN: SAE buffer too short for confirm"); return -1; } buf_len -= 2; data += 2; alg = WPA_GET_LE16(data); seq = WPA_GET_LE16(data + 2); status = WPA_GET_LE16(data + 4); wpa_printf(MSG_DEBUG, "PASN: SAE confirm: alg=%u, seq=%u, status=%u", alg, seq, status); if (alg != WLAN_AUTH_SAE || seq != 2 || status != WLAN_STATUS_SUCCESS) { wpa_printf(MSG_DEBUG, "PASN: Dropping peer SAE confirm"); return -1; } res = sae_check_confirm(&pasn->sae, data + 6, len - 6, NULL); if (res != WLAN_STATUS_SUCCESS) { wpa_printf(MSG_DEBUG, "PASN: SAE failed checking confirm"); return -1; } wpa_printf(MSG_DEBUG, "PASN: SAE completed successfully"); pasn->sae.state = SAE_ACCEPTED; return 0; } static struct wpabuf * wpas_pasn_wd_sae_confirm(struct pasn_data *pasn) { struct wpabuf *buf = NULL; /* Need to add the entire authentication frame body */ buf = wpabuf_alloc(6 + SAE_CONFIRM_MAX_LEN); if (!buf) { wpa_printf(MSG_DEBUG, "PASN: Failed to allocate SAE buffer"); return NULL; } wpabuf_put_le16(buf, WLAN_AUTH_SAE); wpabuf_put_le16(buf, 2); wpabuf_put_le16(buf, WLAN_STATUS_SUCCESS); sae_write_confirm(&pasn->sae, buf); pasn->sae.state = SAE_CONFIRMED; return buf; } #endif /* CONFIG_SAE */ #ifdef CONFIG_FILS static struct wpabuf * wpas_pasn_fils_build_auth(struct pasn_data *pasn) { struct wpabuf *buf = NULL; struct wpabuf *erp_msg; int ret; erp_msg = eapol_sm_build_erp_reauth_start(pasn->eapol); if (!erp_msg) { wpa_printf(MSG_DEBUG, "PASN: FILS: ERP EAP-Initiate/Re-auth unavailable"); return NULL; } if (random_get_bytes(pasn->fils.nonce, FILS_NONCE_LEN) < 0 || random_get_bytes(pasn->fils.session, FILS_SESSION_LEN) < 0) goto fail; wpa_hexdump(MSG_DEBUG, "PASN: FILS: Nonce", pasn->fils.nonce, FILS_NONCE_LEN); wpa_hexdump(MSG_DEBUG, "PASN: FILS: Session", pasn->fils.session, FILS_SESSION_LEN); buf = wpabuf_alloc(1500); if (!buf) goto fail; /* Add the authentication algorithm */ wpabuf_put_le16(buf, WLAN_AUTH_FILS_SK); /* Authentication Transaction seq# */ wpabuf_put_le16(buf, 1); /* Status Code */ wpabuf_put_le16(buf, WLAN_STATUS_SUCCESS); /* Own RSNE */ wpa_pasn_add_rsne(buf, NULL, pasn->akmp, pasn->cipher); /* FILS Nonce */ wpabuf_put_u8(buf, WLAN_EID_EXTENSION); wpabuf_put_u8(buf, 1 + FILS_NONCE_LEN); wpabuf_put_u8(buf, WLAN_EID_EXT_FILS_NONCE); wpabuf_put_data(buf, pasn->fils.nonce, FILS_NONCE_LEN); /* FILS Session */ wpabuf_put_u8(buf, WLAN_EID_EXTENSION); wpabuf_put_u8(buf, 1 + FILS_SESSION_LEN); wpabuf_put_u8(buf, WLAN_EID_EXT_FILS_SESSION); wpabuf_put_data(buf, pasn->fils.session, FILS_SESSION_LEN); /* Wrapped Data (ERP) */ wpabuf_put_u8(buf, WLAN_EID_EXTENSION); wpabuf_put_u8(buf, 1 + wpabuf_len(erp_msg)); wpabuf_put_u8(buf, WLAN_EID_EXT_WRAPPED_DATA); wpabuf_put_buf(buf, erp_msg); /* * Calculate pending PMKID here so that we do not need to maintain a * copy of the EAP-Initiate/Reauth message. */ ret = fils_pmkid_erp(pasn->akmp, wpabuf_head(erp_msg), wpabuf_len(erp_msg), pasn->fils.erp_pmkid); if (ret) { wpa_printf(MSG_DEBUG, "PASN: FILS: Failed to get ERP PMKID"); goto fail; } wpabuf_free(erp_msg); erp_msg = NULL; wpa_hexdump_buf(MSG_DEBUG, "PASN: FILS: Authentication frame", buf); return buf; fail: wpabuf_free(erp_msg); wpabuf_free(buf); return NULL; } static struct wpabuf * wpas_pasn_wd_fils_auth(struct pasn_data *pasn) { wpa_printf(MSG_DEBUG, "PASN: FILS: wrapped data - completed=%u", pasn->fils.completed); /* Nothing to add as we are done */ if (pasn->fils.completed) return NULL; if (!pasn->fils_eapol) { wpa_printf(MSG_DEBUG, "PASN: FILS: Missing Indication IE or PFS"); return NULL; } return wpas_pasn_fils_build_auth(pasn); } static int wpas_pasn_wd_fils_rx(struct pasn_data *pasn, struct wpabuf *wd) { struct ieee802_11_elems elems; struct wpa_ie_data rsne_data; u8 rmsk[ERP_MAX_KEY_LEN]; size_t rmsk_len; u8 anonce[FILS_NONCE_LEN]; const u8 *data; size_t buf_len; struct wpabuf *fils_wd = NULL; u16 alg, seq, status; int ret; if (!wd) return -1; data = wpabuf_head(wd); buf_len = wpabuf_len(wd); wpa_hexdump(MSG_DEBUG, "PASN: FILS: Authentication frame len=%zu", data, buf_len); /* first handle the header */ if (buf_len < 6) { wpa_printf(MSG_DEBUG, "PASN: FILS: Buffer too short"); return -1; } alg = WPA_GET_LE16(data); seq = WPA_GET_LE16(data + 2); status = WPA_GET_LE16(data + 4); wpa_printf(MSG_DEBUG, "PASN: FILS: commit: alg=%u, seq=%u, status=%u", alg, seq, status); if (alg != WLAN_AUTH_FILS_SK || seq != 2 || status != WLAN_STATUS_SUCCESS) { wpa_printf(MSG_DEBUG, "PASN: FILS: Dropping peer authentication"); return -1; } data += 6; buf_len -= 6; if (ieee802_11_parse_elems(data, buf_len, &elems, 1) == ParseFailed) { wpa_printf(MSG_DEBUG, "PASN: FILS: Could not parse elements"); return -1; } if (!elems.rsn_ie || !elems.fils_nonce || !elems.fils_nonce || !elems.wrapped_data) { wpa_printf(MSG_DEBUG, "PASN: FILS: Missing IEs"); return -1; } ret = wpa_parse_wpa_ie(elems.rsn_ie - 2, elems.rsn_ie_len + 2, &rsne_data); if (ret) { wpa_printf(MSG_DEBUG, "PASN: FILS: Failed parsing RSNE"); return -1; } ret = wpa_pasn_validate_rsne(&rsne_data); if (ret) { wpa_printf(MSG_DEBUG, "PASN: FILS: Failed validating RSNE"); return -1; } if (rsne_data.num_pmkid) { wpa_printf(MSG_DEBUG, "PASN: FILS: Not expecting PMKID in RSNE"); return -1; } wpa_hexdump(MSG_DEBUG, "PASN: FILS: ANonce", elems.fils_nonce, FILS_NONCE_LEN); os_memcpy(anonce, elems.fils_nonce, FILS_NONCE_LEN); wpa_hexdump(MSG_DEBUG, "PASN: FILS: FILS Session", elems.fils_session, FILS_SESSION_LEN); if (os_memcmp(pasn->fils.session, elems.fils_session, FILS_SESSION_LEN)) { wpa_printf(MSG_DEBUG, "PASN: FILS: Session mismatch"); return -1; } fils_wd = ieee802_11_defrag(elems.wrapped_data, elems.wrapped_data_len, true); if (!fils_wd) { wpa_printf(MSG_DEBUG, "PASN: FILS: Failed getting wrapped data"); return -1; } eapol_sm_process_erp_finish(pasn->eapol, wpabuf_head(fils_wd), wpabuf_len(fils_wd)); wpabuf_free(fils_wd); fils_wd = NULL; if (eapol_sm_failed(pasn->eapol)) { wpa_printf(MSG_DEBUG, "PASN: FILS: ERP finish failed"); return -1; } rmsk_len = ERP_MAX_KEY_LEN; ret = eapol_sm_get_key(pasn->eapol, rmsk, rmsk_len); if (ret == PMK_LEN) { rmsk_len = PMK_LEN; ret = eapol_sm_get_key(pasn->eapol, rmsk, rmsk_len); } if (ret) { wpa_printf(MSG_DEBUG, "PASN: FILS: Failed getting RMSK"); return -1; } ret = fils_rmsk_to_pmk(pasn->akmp, rmsk, rmsk_len, pasn->fils.nonce, anonce, NULL, 0, pasn->pmk, &pasn->pmk_len); forced_memzero(rmsk, sizeof(rmsk)); if (ret) { wpa_printf(MSG_DEBUG, "PASN: FILS: Failed to derive PMK"); return -1; } wpa_hexdump(MSG_DEBUG, "PASN: FILS: PMKID", pasn->fils.erp_pmkid, PMKID_LEN); wpa_printf(MSG_DEBUG, "PASN: FILS: ERP processing succeeded"); pasn->pmksa_entry = pmksa_cache_add(pasn->pmksa, pasn->pmk, pasn->pmk_len, pasn->fils.erp_pmkid, NULL, 0, pasn->peer_addr, pasn->own_addr, NULL, pasn->akmp, 0); pasn->fils.completed = true; return 0; } #endif /* CONFIG_FILS */ static struct wpabuf * wpas_pasn_get_wrapped_data(struct pasn_data *pasn) { if (pasn->using_pmksa) return NULL; switch (pasn->akmp) { case WPA_KEY_MGMT_PASN: /* no wrapped data */ return NULL; case WPA_KEY_MGMT_SAE: #ifdef CONFIG_SAE if (pasn->trans_seq == 0) return wpas_pasn_wd_sae_commit(pasn); if (pasn->trans_seq == 2) return wpas_pasn_wd_sae_confirm(pasn); #endif /* CONFIG_SAE */ wpa_printf(MSG_ERROR, "PASN: SAE: Cannot derive wrapped data"); return NULL; case WPA_KEY_MGMT_FILS_SHA256: case WPA_KEY_MGMT_FILS_SHA384: #ifdef CONFIG_FILS return wpas_pasn_wd_fils_auth(pasn); #endif /* CONFIG_FILS */ case WPA_KEY_MGMT_FT_PSK: case WPA_KEY_MGMT_FT_IEEE8021X: case WPA_KEY_MGMT_FT_IEEE8021X_SHA384: /* * Wrapped data with these AKMs is optional and is only needed * for further validation of FT security parameters. For now do * not use them. */ return NULL; default: wpa_printf(MSG_ERROR, "PASN: TODO: Wrapped data for akmp=0x%x", pasn->akmp); return NULL; } } static u8 wpas_pasn_get_wrapped_data_format(struct pasn_data *pasn) { if (pasn->using_pmksa) return WPA_PASN_WRAPPED_DATA_NO; /* Note: Valid AKMP is expected to already be validated */ switch (pasn->akmp) { case WPA_KEY_MGMT_SAE: return WPA_PASN_WRAPPED_DATA_SAE; case WPA_KEY_MGMT_FILS_SHA256: case WPA_KEY_MGMT_FILS_SHA384: return WPA_PASN_WRAPPED_DATA_FILS_SK; case WPA_KEY_MGMT_FT_PSK: case WPA_KEY_MGMT_FT_IEEE8021X: case WPA_KEY_MGMT_FT_IEEE8021X_SHA384: /* * Wrapped data with these AKMs is optional and is only needed * for further validation of FT security parameters. For now do * not use them. */ return WPA_PASN_WRAPPED_DATA_NO; case WPA_KEY_MGMT_PASN: default: return WPA_PASN_WRAPPED_DATA_NO; } } static struct wpabuf * wpas_pasn_build_auth_1(struct pasn_data *pasn, const struct wpabuf *comeback, bool verify) { struct wpabuf *buf, *pubkey = NULL, *wrapped_data_buf = NULL; const u8 *pmkid; u8 wrapped_data; int ret; wpa_printf(MSG_DEBUG, "PASN: Building frame 1"); if (pasn->trans_seq) return NULL; buf = wpabuf_alloc(1500); if (!buf) goto fail; /* Get public key */ pubkey = crypto_ecdh_get_pubkey(pasn->ecdh, 0); pubkey = wpabuf_zeropad(pubkey, crypto_ecdh_prime_len(pasn->ecdh)); if (!pubkey) { wpa_printf(MSG_DEBUG, "PASN: Failed to get pubkey"); goto fail; } wrapped_data = wpas_pasn_get_wrapped_data_format(pasn); wpa_pasn_build_auth_header(buf, pasn->bssid, pasn->own_addr, pasn->peer_addr, pasn->trans_seq + 1, WLAN_STATUS_SUCCESS); pmkid = NULL; if (wpa_key_mgmt_ft(pasn->akmp)) { #ifdef CONFIG_IEEE80211R pmkid = pasn->pmk_r1_name; #else /* CONFIG_IEEE80211R */ goto fail; #endif /* CONFIG_IEEE80211R */ } else if (wrapped_data != WPA_PASN_WRAPPED_DATA_NO) { struct rsn_pmksa_cache_entry *pmksa; pmksa = pmksa_cache_get(pasn->pmksa, pasn->peer_addr, pasn->own_addr, NULL, NULL, pasn->akmp); if (pmksa && pasn->custom_pmkid_valid) pmkid = pasn->custom_pmkid; else if (pmksa) pmkid = pmksa->pmkid; /* * Note: Even when PMKSA is available, also add wrapped data as * it is possible that the PMKID is no longer valid at the AP. */ if (!verify) wrapped_data_buf = wpas_pasn_get_wrapped_data(pasn); } if (wpa_pasn_add_rsne(buf, pmkid, pasn->akmp, pasn->cipher) < 0) goto fail; if (!wrapped_data_buf) wrapped_data = WPA_PASN_WRAPPED_DATA_NO; wpa_pasn_add_parameter_ie(buf, pasn->group, wrapped_data, pubkey, true, comeback, -1); if (wpa_pasn_add_wrapped_data(buf, wrapped_data_buf) < 0) goto fail; wpa_pasn_add_rsnxe(buf, pasn->rsnxe_capab); wpa_pasn_add_extra_ies(buf, pasn->extra_ies, pasn->extra_ies_len); ret = pasn_auth_frame_hash(pasn->akmp, pasn->cipher, wpabuf_head_u8(buf) + IEEE80211_HDRLEN, wpabuf_len(buf) - IEEE80211_HDRLEN, pasn->hash); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed to compute hash"); goto fail; } pasn->trans_seq++; wpabuf_free(wrapped_data_buf); wpabuf_free(pubkey); wpa_printf(MSG_DEBUG, "PASN: Frame 1: Success"); return buf; fail: pasn->status = WLAN_STATUS_UNSPECIFIED_FAILURE; wpabuf_free(wrapped_data_buf); wpabuf_free(pubkey); wpabuf_free(buf); return NULL; } static struct wpabuf * wpas_pasn_build_auth_3(struct pasn_data *pasn) { struct wpabuf *buf, *wrapped_data_buf = NULL; u8 mic[WPA_PASN_MAX_MIC_LEN]; u8 mic_len, data_len; const u8 *data; u8 *ptr; u8 wrapped_data; int ret; wpa_printf(MSG_DEBUG, "PASN: Building frame 3"); if (pasn->trans_seq != 2) return NULL; buf = wpabuf_alloc(1500); if (!buf) goto fail; wrapped_data = wpas_pasn_get_wrapped_data_format(pasn); wpa_pasn_build_auth_header(buf, pasn->bssid, pasn->own_addr, pasn->peer_addr, pasn->trans_seq + 1, WLAN_STATUS_SUCCESS); wrapped_data_buf = wpas_pasn_get_wrapped_data(pasn); if (!wrapped_data_buf) wrapped_data = WPA_PASN_WRAPPED_DATA_NO; wpa_pasn_add_parameter_ie(buf, pasn->group, wrapped_data, NULL, false, NULL, -1); if (wpa_pasn_add_wrapped_data(buf, wrapped_data_buf) < 0) goto fail; wpabuf_free(wrapped_data_buf); wrapped_data_buf = NULL; /* Add the MIC */ mic_len = pasn_mic_len(pasn->akmp, pasn->cipher); wpabuf_put_u8(buf, WLAN_EID_MIC); wpabuf_put_u8(buf, mic_len); ptr = wpabuf_put(buf, mic_len); os_memset(ptr, 0, mic_len); data = wpabuf_head_u8(buf) + IEEE80211_HDRLEN; data_len = wpabuf_len(buf) - IEEE80211_HDRLEN; ret = pasn_mic(pasn->ptk.kck, pasn->akmp, pasn->cipher, pasn->own_addr, pasn->peer_addr, pasn->hash, mic_len * 2, data, data_len, mic); if (ret) { wpa_printf(MSG_DEBUG, "PASN: frame 3: Failed MIC calculation"); goto fail; } #ifdef CONFIG_TESTING_OPTIONS if (pasn->corrupt_mic) { wpa_printf(MSG_DEBUG, "PASN: frame 3: Corrupt MIC"); mic[0] = ~mic[0]; } #endif /* CONFIG_TESTING_OPTIONS */ os_memcpy(ptr, mic, mic_len); pasn->trans_seq++; wpa_printf(MSG_DEBUG, "PASN: frame 3: Success"); return buf; fail: pasn->status = WLAN_STATUS_UNSPECIFIED_FAILURE; wpabuf_free(wrapped_data_buf); wpabuf_free(buf); return NULL; } void wpa_pasn_reset(struct pasn_data *pasn) { wpa_printf(MSG_DEBUG, "PASN: Reset"); crypto_ecdh_deinit(pasn->ecdh); pasn->ecdh = NULL; pasn->akmp = 0; pasn->cipher = 0; pasn->group = 0; pasn->trans_seq = 0; pasn->pmk_len = 0; pasn->using_pmksa = false; forced_memzero(pasn->pmk, sizeof(pasn->pmk)); forced_memzero(&pasn->ptk, sizeof(pasn->ptk)); forced_memzero(&pasn->hash, sizeof(pasn->hash)); wpabuf_free(pasn->beacon_rsne_rsnxe); pasn->beacon_rsne_rsnxe = NULL; wpabuf_free(pasn->comeback); pasn->comeback = NULL; pasn->comeback_after = 0; #ifdef CONFIG_SAE sae_clear_data(&pasn->sae); if (pasn->pt) { sae_deinit_pt(pasn->pt); pasn->pt = NULL; } #endif /* CONFIG_SAE */ #ifdef CONFIG_FILS pasn->fils_eapol = false; os_memset(&pasn->fils, 0, sizeof(pasn->fils)); #endif /* CONFIG_FILS*/ #ifdef CONFIG_IEEE80211R forced_memzero(pasn->pmk_r1, sizeof(pasn->pmk_r1)); pasn->pmk_r1_len = 0; os_memset(pasn->pmk_r1_name, 0, sizeof(pasn->pmk_r1_name)); #endif /* CONFIG_IEEE80211R */ pasn->status = WLAN_STATUS_UNSPECIFIED_FAILURE; pasn->pmksa_entry = NULL; #ifdef CONFIG_TESTING_OPTIONS pasn->corrupt_mic = 0; #endif /* CONFIG_TESTING_OPTIONS */ pasn->network_id = 0; pasn->derive_kdk = false; pasn->rsn_ie = NULL; pasn->rsn_ie_len = 0; pasn->rsnxe_ie = NULL; pasn->custom_pmkid_valid = false; if (pasn->extra_ies) { os_free((u8 *) pasn->extra_ies); pasn->extra_ies = NULL; } } static int wpas_pasn_set_pmk(struct pasn_data *pasn, struct wpa_ie_data *rsn_data, struct wpa_pasn_params_data *pasn_data, struct wpabuf *wrapped_data) { static const u8 pasn_default_pmk[] = {'P', 'M', 'K', 'z'}; os_memset(pasn->pmk, 0, sizeof(pasn->pmk)); pasn->pmk_len = 0; if (pasn->akmp == WPA_KEY_MGMT_PASN) { wpa_printf(MSG_DEBUG, "PASN: Using default PMK"); pasn->pmk_len = WPA_PASN_PMK_LEN; os_memcpy(pasn->pmk, pasn_default_pmk, sizeof(pasn_default_pmk)); return 0; } if (wpa_key_mgmt_ft(pasn->akmp)) { #ifdef CONFIG_IEEE80211R wpa_printf(MSG_DEBUG, "PASN: FT: Using PMK-R1"); pasn->pmk_len = pasn->pmk_r1_len; os_memcpy(pasn->pmk, pasn->pmk_r1, pasn->pmk_r1_len); pasn->using_pmksa = true; return 0; #else /* CONFIG_IEEE80211R */ wpa_printf(MSG_DEBUG, "PASN: FT: Not supported"); return -1; #endif /* CONFIG_IEEE80211R */ } if (rsn_data->num_pmkid) { int ret; struct rsn_pmksa_cache_entry *pmksa; const u8 *pmkid = NULL; if (pasn->custom_pmkid_valid) { ret = pasn->validate_custom_pmkid(pasn->cb_ctx, pasn->peer_addr, rsn_data->pmkid); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed custom PMKID validation"); return -1; } } else { pmkid = rsn_data->pmkid; } pmksa = pmksa_cache_get(pasn->pmksa, pasn->peer_addr, pasn->own_addr, pmkid, NULL, pasn->akmp); if (pmksa) { wpa_printf(MSG_DEBUG, "PASN: Using PMKSA"); pasn->pmk_len = pmksa->pmk_len; os_memcpy(pasn->pmk, pmksa->pmk, pmksa->pmk_len); pasn->using_pmksa = true; return 0; } } #ifdef CONFIG_SAE if (pasn->akmp == WPA_KEY_MGMT_SAE) { int ret; ret = wpas_pasn_wd_sae_rx(pasn, wrapped_data); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed processing SAE wrapped data"); pasn->status = WLAN_STATUS_UNSPECIFIED_FAILURE; return -1; } wpa_printf(MSG_DEBUG, "PASN: Success deriving PMK with SAE"); pasn->pmk_len = PMK_LEN; os_memcpy(pasn->pmk, pasn->sae.pmk, PMK_LEN); pasn->pmksa_entry = pmksa_cache_add(pasn->pmksa, pasn->pmk, pasn->pmk_len, pasn->sae.pmkid, NULL, 0, pasn->peer_addr, pasn->own_addr, NULL, pasn->akmp, 0); return 0; } #endif /* CONFIG_SAE */ #ifdef CONFIG_FILS if (pasn->akmp == WPA_KEY_MGMT_FILS_SHA256 || pasn->akmp == WPA_KEY_MGMT_FILS_SHA384) { int ret; ret = wpas_pasn_wd_fils_rx(pasn, wrapped_data); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed processing FILS wrapped data"); pasn->status = WLAN_STATUS_UNSPECIFIED_FAILURE; return -1; } return 0; } #endif /* CONFIG_FILS */ /* TODO: Derive PMK based on wrapped data */ wpa_printf(MSG_DEBUG, "PASN: Missing implementation to derive PMK"); pasn->status = WLAN_STATUS_UNSPECIFIED_FAILURE; return -1; } static int wpas_pasn_send_auth_1(struct pasn_data *pasn, const u8 *own_addr, const u8 *peer_addr, const u8 *bssid, int akmp, int cipher, u16 group, int freq, const u8 *beacon_rsne, u8 beacon_rsne_len, const u8 *beacon_rsnxe, u8 beacon_rsnxe_len, const struct wpabuf *comeback, bool verify) { struct wpabuf *frame; int ret; pasn->ecdh = crypto_ecdh_init(group); if (!pasn->ecdh) { wpa_printf(MSG_DEBUG, "PASN: Failed to init ECDH"); goto fail; } if (beacon_rsne && beacon_rsne_len) { pasn->beacon_rsne_rsnxe = wpabuf_alloc(beacon_rsne_len + beacon_rsnxe_len); if (!pasn->beacon_rsne_rsnxe) { wpa_printf(MSG_DEBUG, "PASN: Failed storing beacon RSNE/RSNXE"); goto fail; } wpabuf_put_data(pasn->beacon_rsne_rsnxe, beacon_rsne, beacon_rsne_len); if (beacon_rsnxe && beacon_rsnxe_len) wpabuf_put_data(pasn->beacon_rsne_rsnxe, beacon_rsnxe, beacon_rsnxe_len); } pasn->akmp = akmp; pasn->cipher = cipher; pasn->group = group; pasn->freq = freq; os_memcpy(pasn->own_addr, own_addr, ETH_ALEN); os_memcpy(pasn->peer_addr, peer_addr, ETH_ALEN); os_memcpy(pasn->bssid, bssid, ETH_ALEN); wpa_printf(MSG_DEBUG, "PASN: Init%s: " MACSTR " akmp=0x%x, cipher=0x%x, group=%u", verify ? " (verify)" : "", MAC2STR(pasn->peer_addr), pasn->akmp, pasn->cipher, pasn->group); frame = wpas_pasn_build_auth_1(pasn, comeback, verify); if (!frame) { wpa_printf(MSG_DEBUG, "PASN: Failed building 1st auth frame"); goto fail; } ret = pasn->send_mgmt(pasn->cb_ctx, wpabuf_head(frame), wpabuf_len(frame), 0, pasn->freq, 1000); wpabuf_free(frame); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed sending 1st auth frame"); goto fail; } return 0; fail: return -1; } int wpas_pasn_start(struct pasn_data *pasn, const u8 *own_addr, const u8 *peer_addr, const u8 *bssid, int akmp, int cipher, u16 group, int freq, const u8 *beacon_rsne, u8 beacon_rsne_len, const u8 *beacon_rsnxe, u8 beacon_rsnxe_len, const struct wpabuf *comeback) { /* TODO: Currently support only ECC groups */ if (!dragonfly_suitable_group(group, 1)) { wpa_printf(MSG_DEBUG, "PASN: Reject unsuitable group %u", group); return -1; } switch (akmp) { case WPA_KEY_MGMT_PASN: break; #ifdef CONFIG_SAE case WPA_KEY_MGMT_SAE: if (beacon_rsnxe && !ieee802_11_rsnx_capab(beacon_rsnxe, WLAN_RSNX_CAPAB_SAE_H2E)) { wpa_printf(MSG_DEBUG, "PASN: AP does not support SAE H2E"); return -1; } pasn->sae.state = SAE_NOTHING; pasn->sae.send_confirm = 0; break; #endif /* CONFIG_SAE */ #ifdef CONFIG_FILS case WPA_KEY_MGMT_FILS_SHA256: case WPA_KEY_MGMT_FILS_SHA384: break; #endif /* CONFIG_FILS */ #ifdef CONFIG_IEEE80211R case WPA_KEY_MGMT_FT_PSK: case WPA_KEY_MGMT_FT_IEEE8021X: case WPA_KEY_MGMT_FT_IEEE8021X_SHA384: break; #endif /* CONFIG_IEEE80211R */ default: wpa_printf(MSG_ERROR, "PASN: Unsupported AKMP=0x%x", akmp); return -1; } return wpas_pasn_send_auth_1(pasn, own_addr, peer_addr, bssid, akmp, cipher, group, freq, beacon_rsne, beacon_rsne_len, beacon_rsnxe, beacon_rsnxe_len, comeback, false); } /* * Wi-Fi Aware uses PASN handshake to authenticate peer devices. * Devices can simply verify each other for subsequent sessions using * pairing verification procedure. * * In pairing verification, Wi-Fi aware devices use PASN authentication * frames with a custom PMKID and Wi-Fi Aware R4 specific verification IEs. * It does not use wrapped data in the Authentication frames. This function * provides support to construct PASN Authentication frames for pairing * verification. */ int wpa_pasn_verify(struct pasn_data *pasn, const u8 *own_addr, const u8 *peer_addr, const u8 *bssid, int akmp, int cipher, u16 group, int freq, const u8 *beacon_rsne, u8 beacon_rsne_len, const u8 *beacon_rsnxe, u8 beacon_rsnxe_len, const struct wpabuf *comeback) { return wpas_pasn_send_auth_1(pasn, own_addr, peer_addr, bssid, akmp, cipher, group, freq, beacon_rsne, beacon_rsne_len, beacon_rsnxe, beacon_rsnxe_len, comeback, true); } static bool is_pasn_auth_frame(struct pasn_data *pasn, const struct ieee80211_mgmt *mgmt, size_t len, bool rx) { u16 fc; if (!mgmt || len < offsetof(struct ieee80211_mgmt, u.auth.variable)) return false; /* Not an Authentication frame; do nothing */ fc = le_to_host16(mgmt->frame_control); if (WLAN_FC_GET_TYPE(fc) != WLAN_FC_TYPE_MGMT || WLAN_FC_GET_STYPE(fc) != WLAN_FC_STYPE_AUTH) return false; /* Not our frame; do nothing */ if (!ether_addr_equal(mgmt->bssid, pasn->bssid)) return false; if (rx && (!ether_addr_equal(mgmt->da, pasn->own_addr) || !ether_addr_equal(mgmt->sa, pasn->peer_addr))) return false; if (!rx && (!ether_addr_equal(mgmt->sa, pasn->own_addr) || !ether_addr_equal(mgmt->da, pasn->peer_addr))) return false; /* Not PASN; do nothing */ if (mgmt->u.auth.auth_alg != host_to_le16(WLAN_AUTH_PASN)) return false; return true; } int wpa_pasn_auth_rx(struct pasn_data *pasn, const u8 *data, size_t len, struct wpa_pasn_params_data *pasn_params) { struct ieee802_11_elems elems; struct wpa_ie_data rsn_data; const struct ieee80211_mgmt *mgmt = (const struct ieee80211_mgmt *) data; struct wpabuf *wrapped_data = NULL, *secret = NULL, *frame = NULL; u8 mic[WPA_PASN_MAX_MIC_LEN], out_mic[WPA_PASN_MAX_MIC_LEN]; u8 mic_len; u16 status; int ret, inc_y; u8 *copy = NULL; size_t mic_offset, copy_len; if (!is_pasn_auth_frame(pasn, mgmt, len, true)) return -2; if (mgmt->u.auth.auth_transaction != host_to_le16(pasn->trans_seq + 1)) { wpa_printf(MSG_DEBUG, "PASN: RX: Invalid transaction sequence: (%u != %u)", le_to_host16(mgmt->u.auth.auth_transaction), pasn->trans_seq + 1); return -3; } status = le_to_host16(mgmt->u.auth.status_code); if (status != WLAN_STATUS_SUCCESS && status != WLAN_STATUS_ASSOC_REJECTED_TEMPORARILY) { wpa_printf(MSG_DEBUG, "PASN: Authentication rejected - status=%u", status); goto fail; } if (ieee802_11_parse_elems(mgmt->u.auth.variable, len - offsetof(struct ieee80211_mgmt, u.auth.variable), &elems, 0) == ParseFailed) { wpa_printf(MSG_DEBUG, "PASN: Failed parsing Authentication frame"); goto fail; } /* Check that the MIC IE exists. Save it and zero out the memory */ mic_len = pasn_mic_len(pasn->akmp, pasn->cipher); if (status == WLAN_STATUS_SUCCESS) { if (!elems.mic || elems.mic_len != mic_len) { wpa_printf(MSG_DEBUG, "PASN: Invalid MIC. Expecting len=%u", mic_len); goto fail; } os_memcpy(mic, elems.mic, mic_len); } if (!elems.pasn_params || !elems.pasn_params_len) { wpa_printf(MSG_DEBUG, "PASN: Missing PASN Parameters IE"); goto fail; } if (!pasn_params) { wpa_printf(MSG_DEBUG, "PASN: pasn_params == NULL"); goto fail; } ret = wpa_pasn_parse_parameter_ie(elems.pasn_params - 3, elems.pasn_params_len + 3, true, pasn_params); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed validation PASN of Parameters IE"); goto fail; } if (status == WLAN_STATUS_ASSOC_REJECTED_TEMPORARILY) { wpa_printf(MSG_DEBUG, "PASN: Authentication temporarily rejected"); if (pasn_params->comeback && pasn_params->comeback_len) { wpa_printf(MSG_DEBUG, "PASN: Comeback token available. After=%u", pasn_params->after); if (!pasn_params->after) return 1; pasn->comeback = wpabuf_alloc_copy( pasn_params->comeback, pasn_params->comeback_len); if (pasn->comeback) pasn->comeback_after = pasn_params->after; } pasn->status = status; goto fail; } if (!elems.rsn_ie) { wpa_printf(MSG_DEBUG, "PASN: Missing RSNE"); goto fail; } ret = wpa_parse_wpa_ie(elems.rsn_ie - 2, elems.rsn_ie_len + 2, &rsn_data); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed parsing RSNE"); goto fail; } ret = wpa_pasn_validate_rsne(&rsn_data); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed validating RSNE"); goto fail; } if (pasn->akmp != rsn_data.key_mgmt || pasn->cipher != rsn_data.pairwise_cipher) { wpa_printf(MSG_DEBUG, "PASN: Mismatch in AKMP/cipher"); goto fail; } if (pasn->group != pasn_params->group) { wpa_printf(MSG_DEBUG, "PASN: Mismatch in group"); goto fail; } if (!pasn_params->pubkey || !pasn_params->pubkey_len) { wpa_printf(MSG_DEBUG, "PASN: Invalid public key"); goto fail; } if (pasn_params->pubkey[0] == WPA_PASN_PUBKEY_UNCOMPRESSED) { inc_y = 1; } else if (pasn_params->pubkey[0] == WPA_PASN_PUBKEY_COMPRESSED_0 || pasn_params->pubkey[0] == WPA_PASN_PUBKEY_COMPRESSED_1) { inc_y = 0; } else { wpa_printf(MSG_DEBUG, "PASN: Invalid first octet in pubkey=0x%x", pasn_params->pubkey[0]); goto fail; } secret = crypto_ecdh_set_peerkey(pasn->ecdh, inc_y, pasn_params->pubkey + 1, pasn_params->pubkey_len - 1); if (!secret) { wpa_printf(MSG_DEBUG, "PASN: Failed to derive shared secret"); goto fail; } if (pasn_params->wrapped_data_format != WPA_PASN_WRAPPED_DATA_NO) { wrapped_data = ieee802_11_defrag(elems.wrapped_data, elems.wrapped_data_len, true); if (!wrapped_data) { wpa_printf(MSG_DEBUG, "PASN: Missing wrapped data"); goto fail; } } ret = wpas_pasn_set_pmk(pasn, &rsn_data, pasn_params, wrapped_data); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed to set PMK"); goto fail; } ret = pasn_pmk_to_ptk(pasn->pmk, pasn->pmk_len, pasn->own_addr, pasn->peer_addr, wpabuf_head(secret), wpabuf_len(secret), &pasn->ptk, pasn->akmp, pasn->cipher, pasn->kdk_len); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed to derive PTK"); goto fail; } if (pasn->secure_ltf) { ret = wpa_ltf_keyseed(&pasn->ptk, pasn->akmp, pasn->cipher); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed to derive LTF keyseed"); goto fail; } } wpabuf_free(wrapped_data); wrapped_data = NULL; wpabuf_free(secret); secret = NULL; /* Use a copy of the message since we need to clear the MIC field */ if (!elems.mic) goto fail; mic_offset = elems.mic - (const u8 *) &mgmt->u.auth; copy_len = len - offsetof(struct ieee80211_mgmt, u.auth); if (mic_offset + mic_len > copy_len) goto fail; copy = os_memdup(&mgmt->u.auth, copy_len); if (!copy) goto fail; os_memset(copy + mic_offset, 0, mic_len); if (pasn->beacon_rsne_rsnxe) { /* Verify the MIC */ ret = pasn_mic(pasn->ptk.kck, pasn->akmp, pasn->cipher, pasn->peer_addr, pasn->own_addr, wpabuf_head(pasn->beacon_rsne_rsnxe), wpabuf_len(pasn->beacon_rsne_rsnxe), copy, copy_len, out_mic); } else { u8 *rsne_rsnxe; size_t rsne_rsnxe_len = 0; /* * Note: When Beacon rsne_rsnxe is not initialized, it is likely * that this is for Wi-Fi Aware using PASN handshake for which * Beacon RSNE/RSNXE are same as RSNE/RSNXE in the * Authentication frame */ if (elems.rsn_ie && elems.rsn_ie_len) rsne_rsnxe_len += elems.rsn_ie_len + 2; if (elems.rsnxe && elems.rsnxe_len) rsne_rsnxe_len += elems.rsnxe_len + 2; rsne_rsnxe = os_zalloc(rsne_rsnxe_len); if (!rsne_rsnxe) goto fail; if (elems.rsn_ie && elems.rsn_ie_len) os_memcpy(rsne_rsnxe, elems.rsn_ie - 2, elems.rsn_ie_len + 2); if (elems.rsnxe && elems.rsnxe_len) os_memcpy(rsne_rsnxe + elems.rsn_ie_len + 2, elems.rsnxe - 2, elems.rsnxe_len + 2); wpa_hexdump_key(MSG_DEBUG, "PASN: RSN + RSNXE buf", rsne_rsnxe, rsne_rsnxe_len); /* Verify the MIC */ ret = pasn_mic(pasn->ptk.kck, pasn->akmp, pasn->cipher, pasn->peer_addr, pasn->own_addr, rsne_rsnxe, rsne_rsnxe_len, copy, copy_len, out_mic); os_free(rsne_rsnxe); } os_free(copy); copy = NULL; wpa_hexdump_key(MSG_DEBUG, "PASN: Frame MIC", mic, mic_len); if (ret || os_memcmp(mic, out_mic, mic_len) != 0) { wpa_printf(MSG_DEBUG, "PASN: Failed MIC verification"); goto fail; } pasn->trans_seq++; wpa_printf(MSG_DEBUG, "PASN: Success verifying Authentication frame"); frame = wpas_pasn_build_auth_3(pasn); if (!frame) { wpa_printf(MSG_DEBUG, "PASN: Failed building 3rd auth frame"); goto fail; } ret = pasn->send_mgmt(pasn->cb_ctx, wpabuf_head(frame), wpabuf_len(frame), 0, pasn->freq, 100); wpabuf_free(frame); if (ret) { wpa_printf(MSG_DEBUG, "PASN: Failed sending 3st auth frame"); goto fail; } wpa_printf(MSG_DEBUG, "PASN: Success sending last frame. Store PTK"); pasn->status = WLAN_STATUS_SUCCESS; return 0; fail: wpa_printf(MSG_DEBUG, "PASN: Failed RX processing - terminating"); wpabuf_free(wrapped_data); wpabuf_free(secret); os_free(copy); /* * TODO: In case of an error the standard allows to silently drop * the frame and terminate the authentication exchange. However, better * reply to the AP with an error status. */ if (status == WLAN_STATUS_SUCCESS) pasn->status = WLAN_STATUS_UNSPECIFIED_FAILURE; else pasn->status = status; return -1; } int wpa_pasn_auth_tx_status(struct pasn_data *pasn, const u8 *data, size_t data_len, u8 acked) { const struct ieee80211_mgmt *mgmt = (const struct ieee80211_mgmt *) data; wpa_printf(MSG_DEBUG, "PASN: auth_tx_status: acked=%u", acked); if (!is_pasn_auth_frame(pasn, mgmt, data_len, false)) return -1; if (mgmt->u.auth.auth_transaction != host_to_le16(pasn->trans_seq)) { wpa_printf(MSG_ERROR, "PASN: Invalid transaction sequence: (%u != %u)", pasn->trans_seq, le_to_host16(mgmt->u.auth.auth_transaction)); return 0; } wpa_printf(MSG_ERROR, "PASN: auth with trans_seq=%u, acked=%u", pasn->trans_seq, acked); /* * Even if the frame was not acked, do not treat this is an error, and * try to complete the flow, relying on the PASN timeout callback to * clean up. */ if (pasn->trans_seq == 3) { wpa_printf(MSG_DEBUG, "PASN: auth complete with: " MACSTR, MAC2STR(pasn->peer_addr)); /* * Either frame was not ACKed or it was ACKed but the trans_seq * != 1, i.e., not expecting an RX frame, so we are done. */ return 1; } return 0; }