| Message ID | CACYaJDQW9wTFX8zoKMn-VMVPVomvd5CzDYSXjPTXSjQQt4M-Fw@mail.gmail.com |
|---|---|
| State | RFC |
| Headers | show |
| Series | Mesh: Support BIP-CMAC-256, BIP-GMAC-128, BIP-GMAC-256 | expand |
On Tue, Aug 06, 2019 at 01:33:15PM +0800, Ouden.Biz Lin wrote: > Dear There, Hi! > 2) The maximum size of AMPE IE is 160 bytes, not 96 bytes, plus the > two bytes of the IE header. > The 64 bytes added are MGTK [variable] and IGTK [variable] at the > 256 bits crypto. > > Please help to confirm that. Thank you. AMPE max size is (discounting first 2 bytes): pairwise suite (4) + local nonce (32) + peer nonce (32) + *key replay counter (8) + MGTK: MGTK (16), key rsc (8), key expiration (4) IGTK: key id (2), IPN (6), IGTK (16) *only for mesh group key inform frame, we don't use it currently = 128 So, yes, the current code using 96 is already wrong, as it doesn't account for IGTK size: it should be 120 today (because Key Replay Counter is unused). Using 256-bit keys should add another 32 bytes on top of that so we could use 152 here. 160 is correct if we include Key Replay Counter. > +#ifdef CONFIG_IEEE80211W > + if (conf->ieee80211w != NO_MGMT_FRAME_PROTECTION) { > + if (ssid->group_mgmt_cipher & > + WPA_CIPHER_BIP_GMAC_256) The formatting here is rather hard to read, in my opinion. Question, is there a check somewhere that peers are using the same cipher suite for management protection? I looked for it but didn't see it. Possibly matches_local() should be comparing the RSNEs when processing peering open frames?
diff --git a/wpa_supplicant/mesh.c b/wpa_supplicant/mesh.c index 7354c1b79..7dcd6f96c 100644 --- a/wpa_supplicant/mesh.c +++ b/wpa_supplicant/mesh.c @@ -116,8 +116,26 @@ static struct mesh_conf * mesh_config_create(struct wpa_supplicant *wpa_s, } conf->group_cipher = cipher; - if (conf->ieee80211w != NO_MGMT_FRAME_PROTECTION) - conf->mgmt_group_cipher = WPA_CIPHER_AES_128_CMAC; + +#ifdef CONFIG_IEEE80211W + if (conf->ieee80211w != NO_MGMT_FRAME_PROTECTION) { + if (ssid->group_mgmt_cipher & + WPA_CIPHER_BIP_GMAC_256) + conf->mgmt_group_cipher = + WPA_CIPHER_BIP_GMAC_256; + else if (ssid->group_mgmt_cipher & + WPA_CIPHER_BIP_CMAC_256) + conf->mgmt_group_cipher = + WPA_CIPHER_BIP_CMAC_256; + else if (ssid->group_mgmt_cipher & + WPA_CIPHER_BIP_GMAC_128) + conf->mgmt_group_cipher = + WPA_CIPHER_BIP_GMAC_128; + else + conf->mgmt_group_cipher = + WPA_CIPHER_AES_128_CMAC; + } +#endif /* CONFIG_IEEE80211W */ /* defaults */ conf->mesh_pp_id = MESH_PATH_PROTOCOL_HWMP; diff --git a/wpa_supplicant/mesh_mpm.c b/wpa_supplicant/mesh_mpm.c index 4a163b6eb..01b970715 100644 --- a/wpa_supplicant/mesh_mpm.c +++ b/wpa_supplicant/mesh_mpm.c @@ -231,7 +231,7 @@ static void mesh_mpm_send_plink_action(struct wpa_supplicant *wpa_s, 2 + 32 + /* mesh ID */ 2 + 7 + /* mesh config */ 2 + 24 + /* peering management */ - 2 + 96 + /* AMPE */ + 2 + 160 + /* AMPE */ 2 + 16; /* MIC */ #ifdef CONFIG_IEEE80211N
Dear There, Mesh was hardcoded to use BIP-CMAC-128 if PMF was enabled. We hope to extend that to allow the other BIP algorithms to be used. 1) Assign the WPA_CIPHER_BIT_* by the ssid->group_mgmt cipher 2) The maximum size of AMPE IE is 160 bytes, not 96 bytes, plus the two bytes of the IE header. The 64 bytes added are MGTK [variable] and IGTK [variable] at the 256 bits crypto. Please help to confirm that. Thank you. if (type != PLINK_CLOSE && wpa_s->mesh_ht_enabled) {