hostapd/wlantest/ccmp.c
Jouni Malinen c1ce0c3587 wlantest: Use AP MLD address in CCMP/GCMP AAD for A3
Commit b20991da69 ("wlantest: MLD MAC Address in CCMP/GCMP AAD/nonce")
updated AAD and nonce construction to use MLD addresses in AAD for A1
and A2. IEEE P802.11be has additional cases where A3 in AAD is set to
the AP MLD address, so cover those as well.

Signed-off-by: Jouni Malinen <quic_jouni@quicinc.com>
2023-01-10 12:38:59 +02:00

382 lines
9.5 KiB
C

/*
* CTR with CBC-MAC Protocol (CCMP)
* Copyright (c) 2010-2012, Jouni Malinen <j@w1.fi>
*
* 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/ieee802_11_defs.h"
#include "crypto/aes.h"
#include "crypto/aes_wrap.h"
#include "wlantest.h"
static void ccmp_aad_nonce(const struct ieee80211_hdr *hdr, const u8 *data,
const u8 *a1, const u8 *a2, const u8 *a3,
u8 *aad, size_t *aad_len, u8 *nonce)
{
u16 fc, stype, seq;
int qos = 0, addr4 = 0;
u8 *pos;
nonce[0] = 0;
fc = le_to_host16(hdr->frame_control);
stype = WLAN_FC_GET_STYPE(fc);
if ((fc & (WLAN_FC_TODS | WLAN_FC_FROMDS)) ==
(WLAN_FC_TODS | WLAN_FC_FROMDS))
addr4 = 1;
if (WLAN_FC_GET_TYPE(fc) == WLAN_FC_TYPE_DATA) {
fc &= ~0x0070; /* Mask subtype bits */
if (stype & 0x08) {
const u8 *qc;
qos = 1;
fc &= ~WLAN_FC_HTC;
qc = (const u8 *) (hdr + 1);
if (addr4)
qc += ETH_ALEN;
nonce[0] = qc[0] & 0x0f;
}
} else if (WLAN_FC_GET_TYPE(fc) == WLAN_FC_TYPE_MGMT)
nonce[0] |= 0x10; /* Management */
fc &= ~(WLAN_FC_RETRY | WLAN_FC_PWRMGT | WLAN_FC_MOREDATA);
fc |= WLAN_FC_ISWEP;
WPA_PUT_LE16(aad, fc);
pos = aad + 2;
os_memcpy(pos, hdr->addr1, 3 * ETH_ALEN);
if (a1)
os_memcpy(pos, a1, ETH_ALEN);
if (a2)
os_memcpy(pos + ETH_ALEN, a2, ETH_ALEN);
if (a3)
os_memcpy(pos + 2 * ETH_ALEN, a3, ETH_ALEN);
pos += 3 * ETH_ALEN;
seq = le_to_host16(hdr->seq_ctrl);
seq &= ~0xfff0; /* Mask Seq#; do not modify Frag# */
WPA_PUT_LE16(pos, seq);
pos += 2;
os_memcpy(pos, hdr + 1, addr4 * ETH_ALEN + qos * 2);
pos += addr4 * ETH_ALEN;
if (qos) {
pos[0] &= ~0x70;
if (1 /* FIX: either device has SPP A-MSDU Capab = 0 */)
pos[0] &= ~0x80;
pos++;
*pos++ = 0x00;
}
*aad_len = pos - aad;
if (a2)
os_memcpy(nonce + 1, a2, ETH_ALEN);
else
os_memcpy(nonce + 1, hdr->addr2, ETH_ALEN);
nonce[7] = data[7]; /* PN5 */
nonce[8] = data[6]; /* PN4 */
nonce[9] = data[5]; /* PN3 */
nonce[10] = data[4]; /* PN2 */
nonce[11] = data[1]; /* PN1 */
nonce[12] = data[0]; /* PN0 */
}
static void ccmp_aad_nonce_pv1(const u8 *hdr, const u8 *a1, const u8 *a2,
const u8 *a3, const u8 *pn,
u8 *aad, size_t *aad_len, u8 *nonce)
{
u16 fc, type;
u8 *pos;
nonce[0] = BIT(5); /* PV1 */
/* TODO: Priority for QMF; 0 is used for Data frames */
fc = WPA_GET_LE16(hdr);
type = (fc & (BIT(2) | BIT(3) | BIT(4))) >> 2;
if (type == 1)
nonce[0] |= 0x10; /* Management */
fc &= ~(BIT(10) | BIT(11) | BIT(13) | BIT(14) | BIT(15));
fc |= BIT(12);
WPA_PUT_LE16(aad, fc);
pos = aad + 2;
if (type == 0 || type == 3) {
const u8 *sc;
os_memcpy(pos, a1, ETH_ALEN);
pos += ETH_ALEN;
os_memcpy(pos, a2, ETH_ALEN);
pos += ETH_ALEN;
if (type == 0) {
/* Either A1 or A2 contains SID */
sc = hdr + 2 + 2 + ETH_ALEN;
} else {
/* Both A1 and A2 contain full addresses */
sc = hdr + 2 + 2 * ETH_ALEN;
}
/* SC with Sequence Number subfield (bits 4-15 of the Sequence
* Control field) masked to 0. */
*pos++ = *sc & 0x0f;
*pos++ = 0;
if (a3) {
os_memcpy(pos, a3, ETH_ALEN);
pos += ETH_ALEN;
}
}
*aad_len = pos - aad;
os_memcpy(nonce + 1, a2, ETH_ALEN);
nonce[7] = pn[5]; /* PN5 */
nonce[8] = pn[4]; /* PN4 */
nonce[9] = pn[3]; /* PN3 */
nonce[10] = pn[2]; /* PN2 */
nonce[11] = pn[1]; /* PN1 */
nonce[12] = pn[0]; /* PN0 */
}
u8 * ccmp_decrypt(const u8 *tk, const struct ieee80211_hdr *hdr,
const u8 *a1, const u8 *a2, const u8 *a3,
const u8 *data, size_t data_len,
size_t *decrypted_len)
{
u8 aad[30], nonce[13];
size_t aad_len;
size_t mlen;
u8 *plain;
if (data_len < 8 + 8)
return NULL;
plain = os_malloc(data_len + AES_BLOCK_SIZE);
if (plain == NULL)
return NULL;
mlen = data_len - 8 - 8;
os_memset(aad, 0, sizeof(aad));
ccmp_aad_nonce(hdr, data, a1, a2, a3, aad, &aad_len, nonce);
wpa_hexdump(MSG_EXCESSIVE, "CCMP AAD", aad, aad_len);
wpa_hexdump(MSG_EXCESSIVE, "CCMP nonce", nonce, 13);
if (aes_ccm_ad(tk, 16, nonce, 8, data + 8, mlen, aad, aad_len,
data + 8 + mlen, plain) < 0) {
u16 seq_ctrl = le_to_host16(hdr->seq_ctrl);
wpa_printf(MSG_INFO, "Invalid CCMP MIC in frame: A1=" MACSTR
" A2=" MACSTR " A3=" MACSTR " seq=%u frag=%u",
MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
MAC2STR(hdr->addr3),
WLAN_GET_SEQ_SEQ(seq_ctrl),
WLAN_GET_SEQ_FRAG(seq_ctrl));
os_free(plain);
return NULL;
}
wpa_hexdump(MSG_EXCESSIVE, "CCMP decrypted", plain, mlen);
*decrypted_len = mlen;
return plain;
}
void ccmp_get_pn(u8 *pn, const u8 *data)
{
pn[0] = data[7]; /* PN5 */
pn[1] = data[6]; /* PN4 */
pn[2] = data[5]; /* PN3 */
pn[3] = data[4]; /* PN2 */
pn[4] = data[1]; /* PN1 */
pn[5] = data[0]; /* PN0 */
}
u8 * ccmp_encrypt(const u8 *tk, u8 *frame, size_t len, size_t hdrlen,
const u8 *qos, const u8 *a1, const u8 *a2, const u8 *a3,
const u8 *pn, int keyid, size_t *encrypted_len)
{
u8 aad[30], nonce[13];
size_t aad_len, plen;
u8 *crypt, *pos;
struct ieee80211_hdr *hdr;
if (len < hdrlen || hdrlen < 24)
return NULL;
plen = len - hdrlen;
crypt = os_malloc(hdrlen + 8 + plen + 8 + AES_BLOCK_SIZE);
if (crypt == NULL)
return NULL;
os_memcpy(crypt, frame, hdrlen);
hdr = (struct ieee80211_hdr *) crypt;
hdr->frame_control |= host_to_le16(WLAN_FC_ISWEP);
pos = crypt + hdrlen;
*pos++ = pn[5]; /* PN0 */
*pos++ = pn[4]; /* PN1 */
*pos++ = 0x00; /* Rsvd */
*pos++ = 0x20 | (keyid << 6);
*pos++ = pn[3]; /* PN2 */
*pos++ = pn[2]; /* PN3 */
*pos++ = pn[1]; /* PN4 */
*pos++ = pn[0]; /* PN5 */
os_memset(aad, 0, sizeof(aad));
ccmp_aad_nonce(hdr, crypt + hdrlen, a1, a2, a3, aad, &aad_len, nonce);
wpa_hexdump(MSG_EXCESSIVE, "CCMP AAD", aad, aad_len);
wpa_hexdump(MSG_EXCESSIVE, "CCMP nonce", nonce, 13);
if (aes_ccm_ae(tk, 16, nonce, 8, frame + hdrlen, plen, aad, aad_len,
pos, pos + plen) < 0) {
os_free(crypt);
return NULL;
}
wpa_hexdump(MSG_EXCESSIVE, "CCMP encrypted", crypt + hdrlen + 8, plen);
*encrypted_len = hdrlen + 8 + plen + 8;
return crypt;
}
u8 * ccmp_encrypt_pv1(const u8 *tk, const u8 *a1, const u8 *a2, const u8 *a3,
const u8 *frame, size_t len,
size_t hdrlen, const u8 *pn, int keyid,
size_t *encrypted_len)
{
u8 aad[24], nonce[13];
size_t aad_len, plen;
u8 *crypt, *pos;
struct ieee80211_hdr *hdr;
if (len < hdrlen || hdrlen < 12)
return NULL;
plen = len - hdrlen;
crypt = os_malloc(hdrlen + plen + 8 + AES_BLOCK_SIZE);
if (crypt == NULL)
return NULL;
os_memcpy(crypt, frame, hdrlen);
hdr = (struct ieee80211_hdr *) crypt;
hdr->frame_control |= host_to_le16(BIT(12)); /* Protected Frame */
pos = crypt + hdrlen;
os_memset(aad, 0, sizeof(aad));
ccmp_aad_nonce_pv1(crypt, a1, a2, a3, pn, aad, &aad_len, nonce);
wpa_hexdump(MSG_EXCESSIVE, "CCMP AAD", aad, aad_len);
wpa_hexdump(MSG_EXCESSIVE, "CCMP nonce", nonce, sizeof(nonce));
if (aes_ccm_ae(tk, 16, nonce, 8, frame + hdrlen, plen, aad, aad_len,
pos, pos + plen) < 0) {
os_free(crypt);
return NULL;
}
wpa_hexdump(MSG_EXCESSIVE, "CCMP encrypted", crypt + hdrlen, plen);
*encrypted_len = hdrlen + plen + 8;
return crypt;
}
u8 * ccmp_256_decrypt(const u8 *tk, const struct ieee80211_hdr *hdr,
const u8 *a1, const u8 *a2, const u8 *a3,
const u8 *data, size_t data_len, size_t *decrypted_len)
{
u8 aad[30], nonce[13];
size_t aad_len;
size_t mlen;
u8 *plain;
if (data_len < 8 + 16)
return NULL;
plain = os_malloc(data_len + AES_BLOCK_SIZE);
if (plain == NULL)
return NULL;
mlen = data_len - 8 - 16;
os_memset(aad, 0, sizeof(aad));
ccmp_aad_nonce(hdr, data, a1, a2, a3, aad, &aad_len, nonce);
wpa_hexdump(MSG_EXCESSIVE, "CCMP-256 AAD", aad, aad_len);
wpa_hexdump(MSG_EXCESSIVE, "CCMP-256 nonce", nonce, 13);
if (aes_ccm_ad(tk, 32, nonce, 16, data + 8, mlen, aad, aad_len,
data + 8 + mlen, plain) < 0) {
u16 seq_ctrl = le_to_host16(hdr->seq_ctrl);
wpa_printf(MSG_INFO, "Invalid CCMP-256 MIC in frame: A1=" MACSTR
" A2=" MACSTR " A3=" MACSTR " seq=%u frag=%u",
MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
MAC2STR(hdr->addr3),
WLAN_GET_SEQ_SEQ(seq_ctrl),
WLAN_GET_SEQ_FRAG(seq_ctrl));
os_free(plain);
return NULL;
}
wpa_hexdump(MSG_EXCESSIVE, "CCMP-256 decrypted", plain, mlen);
*decrypted_len = mlen;
return plain;
}
u8 * ccmp_256_encrypt(const u8 *tk, u8 *frame, size_t len, size_t hdrlen,
const u8 *qos, const u8 *a1, const u8 *a2, const u8 *a3,
const u8 *pn, int keyid, size_t *encrypted_len)
{
u8 aad[30], nonce[13];
size_t aad_len, plen;
u8 *crypt, *pos;
struct ieee80211_hdr *hdr;
if (len < hdrlen || hdrlen < 24)
return NULL;
plen = len - hdrlen;
crypt = os_malloc(hdrlen + 8 + plen + 16 + AES_BLOCK_SIZE);
if (crypt == NULL)
return NULL;
os_memcpy(crypt, frame, hdrlen);
hdr = (struct ieee80211_hdr *) crypt;
hdr->frame_control |= host_to_le16(WLAN_FC_ISWEP);
pos = crypt + hdrlen;
*pos++ = pn[5]; /* PN0 */
*pos++ = pn[4]; /* PN1 */
*pos++ = 0x00; /* Rsvd */
*pos++ = 0x20 | (keyid << 6);
*pos++ = pn[3]; /* PN2 */
*pos++ = pn[2]; /* PN3 */
*pos++ = pn[1]; /* PN4 */
*pos++ = pn[0]; /* PN5 */
os_memset(aad, 0, sizeof(aad));
ccmp_aad_nonce(hdr, crypt + hdrlen, a1, a2, a3, aad, &aad_len, nonce);
wpa_hexdump(MSG_EXCESSIVE, "CCMP-256 AAD", aad, aad_len);
wpa_hexdump(MSG_EXCESSIVE, "CCMP-256 nonce", nonce, 13);
if (aes_ccm_ae(tk, 32, nonce, 16, frame + hdrlen, plen, aad, aad_len,
pos, pos + plen) < 0) {
os_free(crypt);
return NULL;
}
wpa_hexdump(MSG_EXCESSIVE, "CCMP-256 encrypted", crypt + hdrlen + 8,
plen);
*encrypted_len = hdrlen + 8 + plen + 16;
return crypt;
}