esp-idf/components/wpa_supplicant/src/crypto/ccmp.c
kapil.gupta ad7cb5f5c1 wpa_supplicant: Write Crypto API based on mbedtls
This commit add following crypto changes

1. Update current crypto code with upstream supplicant code
2. Add a proper porting layer to use mbedtls APIs for all the crypto
   operations used by supplicant.

Internal crypto will be used when USE_MBEDLTS flag is disabled
in supplicant's menuconfig.

This commit also removes the clutter in crypto files due to partial
porting of some APIs to mbedtls, all the code from those files have
been removed and rewritten in a generic way, this is inspired from
current upstream code.

This also reduces the lib size significantly, supplicant's lib
size reduces around ~567kb after this change(NB: lib size doesn't
indicate reduction in final bin size).
2021-05-04 10:54:57 +00:00

365 lines
8.6 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.
*/
#ifdef CONFIG_IEEE80211W
#include "utils/includes.h"
#include "utils/common.h"
#include "common/ieee802_11_defs.h"
#include "crypto/aes.h"
#include "crypto/aes_wrap.h"
static void ccmp_aad_nonce(const struct ieee80211_hdr *hdr, const u8 *data,
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_ORDER;
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);
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;
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 u8 *hdr,
const u8 *data, size_t data_len, size_t *decrypted_len, bool espnow_pkt)
{
u8 aad[30], nonce[13];
size_t aad_len;
size_t mlen;
size_t tag_len = 8;
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((const struct ieee80211_hdr *)hdr, data, aad, &aad_len,
nonce);
wpa_hexdump(MSG_DEBUG, "CCMP AAD", aad, aad_len);
wpa_hexdump(MSG_DEBUG, "CCMP nonce", nonce, 13);
#ifdef ESPRESSIF_USE
if (espnow_pkt) {
tag_len = 0;
nonce[0] = 0;
}
#endif
if (aes_ccm_ad(tk, 16, nonce, tag_len, data + 8, mlen, aad, aad_len,
data + 8 + mlen, plain) < 0) {
os_free(plain);
return NULL;
}
wpa_hexdump(MSG_DEBUG, "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,
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, aad, &aad_len, nonce);
wpa_hexdump(MSG_DEBUG, "CCMP AAD", aad, aad_len);
wpa_hexdump(MSG_DEBUG, "CCMP nonce", nonce, 13);
if (aes_ccm_ae(tk, 16, nonce, 8, frame + hdrlen, plen, aad, aad_len,
pos, pos + plen) < 0) {
wpa_printf(MSG_ERROR, "aes ccm ae failed");
os_free(crypt);
return NULL;
}
wpa_hexdump(MSG_DEBUG, "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_DEBUG, "CCMP AAD", aad, aad_len);
wpa_hexdump(MSG_DEBUG, "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_DEBUG, "CCMP encrypted", crypt + hdrlen, plen);
*encrypted_len = hdrlen + plen + 8;
return crypt;
}
u8 * ccmp_256_decrypt(const u8 *tk, const u8 *hdr, 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((const struct ieee80211_hdr *)hdr, data, aad,
&aad_len, nonce);
wpa_hexdump(MSG_DEBUG, "CCMP-256 AAD", aad, aad_len);
wpa_hexdump(MSG_DEBUG, "CCMP-256 nonce", nonce, 13);
if (aes_ccm_ad(tk, 32, nonce, 16, data + 8, mlen, aad, aad_len,
data + 8 + mlen, plain) < 0) {
os_free(plain);
return NULL;
}
wpa_hexdump(MSG_DEBUG, "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,
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, aad, &aad_len, nonce);
wpa_hexdump(MSG_DEBUG, "CCMP-256 AAD", aad, aad_len);
wpa_hexdump(MSG_DEBUG, "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_DEBUG, "CCMP-256 encrypted", crypt + hdrlen + 8,
plen);
*encrypted_len = hdrlen + 8 + plen + 16;
return crypt;
}
#endif /* CONFIG_IEEE80211W */