--- /dev/null
+/*
+ * GCM with GMAC Protocol (GCMP)
+ * Copyright (c) 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 "wlantest.h"
+
+
+static void inc32(u8 *block)
+{
+ u32 val;
+ val = WPA_GET_BE32(block + AES_BLOCK_SIZE - 4);
+ val++;
+ WPA_PUT_BE32(block + AES_BLOCK_SIZE - 4, val);
+}
+
+
+static void xor_block(u8 *dst, const u8 *src)
+{
+ u32 *d = (u32 *) dst;
+ u32 *s = (u32 *) src;
+ *d++ ^= *s++;
+ *d++ ^= *s++;
+ *d++ ^= *s++;
+ *d++ ^= *s++;
+}
+
+
+static void shift_right_block(u8 *v)
+{
+ u32 val;
+
+ val = WPA_GET_BE32(v + 12);
+ val >>= 1;
+ if (v[11] & 0x01)
+ val |= 0x80000000;
+ WPA_PUT_BE32(v + 12, val);
+
+ val = WPA_GET_BE32(v + 8);
+ val >>= 1;
+ if (v[7] & 0x01)
+ val |= 0x80000000;
+ WPA_PUT_BE32(v + 8, val);
+
+ val = WPA_GET_BE32(v + 4);
+ val >>= 1;
+ if (v[3] & 0x01)
+ val |= 0x80000000;
+ WPA_PUT_BE32(v + 4, val);
+
+ val = WPA_GET_BE32(v);
+ val >>= 1;
+ WPA_PUT_BE32(v, val);
+}
+
+
+/* Multiplication in GF(2^128) */
+static void gf_mult(const u8 *x, const u8 *y, u8 *z)
+{
+ u8 v[16];
+ int i, j;
+
+ os_memset(z, 0, 16); /* Z_0 = 0^128 */
+ os_memcpy(v, y, 16); /* V_0 = Y */
+
+ for (i = 0; i < 16; i++) {
+ for (j = 0; j < 8; j++) {
+ if (x[i] & BIT(7 - j)) {
+ /* Z_(i + 1) = Z_i XOR V_i */
+ xor_block(z, v);
+ } else {
+ /* Z_(i + 1) = Z_i */
+ }
+
+ if (v[15] & 0x01) {
+ /* V_(i + 1) = (V_i >> 1) XOR R */
+ shift_right_block(v);
+ /* R = 11100001 || 0^120 */
+ v[0] ^= 0xe1;
+ } else {
+ /* V_(i + 1) = V_i >> 1 */
+ shift_right_block(v);
+ }
+ }
+ }
+}
+
+
+static void ghash(const u8 *h, const u8 *x, size_t xlen, u8 *y)
+{
+ size_t m, i;
+ const u8 *xpos = x;
+ u8 tmp[16];
+
+ m = xlen / 16;
+
+ /* Y_0 = 0^128 */
+ os_memset(y, 0, 16);
+ for (i = 0; i < m; i++) {
+ /* Y_i = (Y^(i-1) XOR X_i) dot H */
+ xor_block(y, xpos);
+ xpos += 16;
+
+ /* dot operation:
+ * multiplication operation for binary Galois (finite) field of
+ * 2^128 elements */
+ gf_mult(y, h, tmp);
+ os_memcpy(y, tmp, 16);
+ }
+
+ /* Return Y_m */
+}
+
+
+static void aes_gctr(void *aes, const u8 *icb, const u8 *x, size_t xlen, u8 *y)
+{
+ size_t i, n, last;
+ u8 cb[AES_BLOCK_SIZE], tmp[AES_BLOCK_SIZE];
+ const u8 *xpos = x;
+ u8 *ypos = y;
+
+ if (xlen == 0)
+ return;
+
+ n = xlen / 16;
+
+ os_memcpy(cb, icb, AES_BLOCK_SIZE);
+ /* Full blocks */
+ for (i = 0; i < n; i++) {
+ aes_encrypt(aes, cb, ypos);
+ xor_block(ypos, xpos);
+ xpos += AES_BLOCK_SIZE;
+ ypos += AES_BLOCK_SIZE;
+ inc32(cb);
+ }
+
+ last = x + xlen - xpos;
+ if (last) {
+ /* Last, partial block */
+ aes_encrypt(aes, cb, tmp);
+ for (i = 0; i < last; i++)
+ *ypos++ = *xpos++ ^ tmp[i];
+ }
+}
+
+
+static void gcmp_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;
+
+ 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;
+ }
+ }
+
+ 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, hdr->addr2, ETH_ALEN);
+ nonce[6] = data[7]; /* PN5 */
+ nonce[7] = data[6]; /* PN4 */
+ nonce[8] = data[5]; /* PN3 */
+ nonce[9] = data[4]; /* PN2 */
+ nonce[10] = data[1]; /* PN1 */
+ nonce[11] = data[0]; /* PN0 */
+}
+
+
+u8 * gcmp_decrypt(const u8 *tk, const struct ieee80211_hdr *hdr,
+ const u8 *data, size_t data_len, size_t *decrypted_len)
+{
+ u8 aad[2 + 30], nonce[12], *plain, *auth, *apos;
+ u8 H[AES_BLOCK_SIZE];
+ u8 J0[AES_BLOCK_SIZE];
+ u8 S[16], T[16];
+ size_t aad_len, padlen, mlen;
+ void *aes;
+ const u8 *m;
+
+ if (data_len < 8 + 16)
+ return NULL;
+
+ plain = os_malloc(data_len + AES_BLOCK_SIZE);
+ if (plain == NULL)
+ return NULL;
+
+ aes = aes_encrypt_init(tk, 16);
+ if (aes == NULL) {
+ os_free(plain);
+ return NULL;
+ }
+
+ m = data + 8;
+ mlen = data_len - 8 - 16;
+
+ os_memset(aad, 0, sizeof(aad));
+ gcmp_aad_nonce(hdr, data, &aad[2], &aad_len, nonce);
+ WPA_PUT_BE16(aad, aad_len);
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP AAD", &aad[2], aad_len);
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP nonce", nonce, sizeof(nonce));
+
+ /* GCM-AD_K(IV, C, A, T)
+ *
+ * IV = GCMP nonce
+ * A = AAD
+ * C | T = received frame
+ */
+
+ /* 2. Generate hash subkey H = AES_K(0^128) */
+ os_memset(H, 0, sizeof(H));
+ aes_encrypt(aes, H, H);
+ wpa_hexdump(MSG_EXCESSIVE, "Hash subkey H for GHASH", H, sizeof(H));
+
+ /* 3. Prepare block J_0 = IV || 0^31 || 1 [len(IV) = 96] */
+ os_memcpy(J0, nonce, sizeof(nonce));
+ os_memset(J0 + sizeof(nonce), 0, AES_BLOCK_SIZE - sizeof(nonce));
+ J0[AES_BLOCK_SIZE - 1] = 0x01;
+
+ /* 4. C = GCTR_K(inc_32(J_0), C) */
+ inc32(J0);
+ aes_gctr(aes, J0, m, mlen, plain);
+
+ /*
+ * 5. u = 128 * ceil[len(C)/128] - len(C)
+ * v = 128 * ceil[len(A)/128] - len(A)
+ * 6. S = GHASH_H(A || 0^v || C || 0^u || [len(A)]64 || [len(C)]64)
+ * (i.e., zero padded to block size A || C and lengths of each in bits)
+ */
+ auth = os_malloc(32 + 16 + data_len - 16 + 8 + 8);
+ if (auth == NULL) {
+ os_free(plain);
+ return NULL;
+ }
+
+ apos = auth;
+
+ /* Zero-padded AAD */
+ os_memcpy(apos, &aad[2], aad_len);
+ apos += aad_len;
+ padlen = (16 - aad_len % 16) % 16;
+ os_memset(apos, 0, padlen);
+ apos += padlen;
+
+ /* Zero-padded C */
+ os_memcpy(apos, m, mlen);
+ apos += mlen;
+ padlen = (16 - mlen % 16) % 16;
+ os_memset(apos, 0, padlen);
+ apos += padlen;
+
+ /* Length of AAD and C in bits */
+ WPA_PUT_BE64(apos, aad_len * 8);
+ apos += 8;
+ WPA_PUT_BE64(apos, mlen * 8);
+ apos += 8;
+
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP GHASH_H input", auth, apos - auth);
+ ghash(H, auth, apos - auth, S);
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP S = GHASH_H(...)", S, 16);
+ os_free(auth);
+
+ /* 7. T' = MSB_t(GCTR_K(J_0, S)) */
+ J0[AES_BLOCK_SIZE - 1] = 0x01;
+ aes_gctr(aes, J0, S, sizeof(S), T);
+
+ aes_encrypt_deinit(aes);
+
+ if (os_memcmp(data + data_len - 16, T, 16) != 0) {
+ u16 seq_ctrl = le_to_host16(hdr->seq_ctrl);
+ wpa_printf(MSG_INFO, "Invalid GCMP 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));
+ wpa_hexdump(MSG_DEBUG, "GCMP decrypted", plain, data_len - 16);
+ os_free(plain);
+ return NULL;
+ }
+
+ *decrypted_len = data_len - 8 - 16;
+ return plain;
+}
+
+
+u8 * gcmp_encrypt(const u8 *tk, u8 *frame, size_t len, size_t hdrlen, u8 *qos,
+ u8 *pn, int keyid, size_t *encrypted_len)
+{
+ u8 aad[2 + 30], nonce[12], *crypt, *pos, *auth, *apos;
+ u8 H[AES_BLOCK_SIZE];
+ u8 J0[AES_BLOCK_SIZE];
+ u8 S[16];
+ size_t aad_len, plen, padlen;
+ struct ieee80211_hdr *hdr;
+ void *aes;
+
+ 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 */
+
+ aes = aes_encrypt_init(tk, 16);
+ if (aes == NULL) {
+ os_free(crypt);
+ return NULL;
+ }
+
+ os_memset(aad, 0, sizeof(aad));
+ gcmp_aad_nonce(hdr, crypt + hdrlen, &aad[2], &aad_len, nonce);
+ WPA_PUT_BE16(aad, aad_len);
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP AAD", &aad[2], aad_len);
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP nonce", nonce, sizeof(nonce));
+
+ /* GCM-AE_K(IV, P, A)
+ *
+ * IV = GCMP nonce
+ * A = AAD
+ */
+
+ /* 1. Generate hash subkey H = AES_K(0^128) */
+ os_memset(H, 0, sizeof(H));
+ aes_encrypt(aes, H, H);
+ wpa_hexdump(MSG_EXCESSIVE, "Hash subkey H for GHASH", H, sizeof(H));
+
+ /* 2. Prepare block J_0 = IV || 0^31 || 1 [len(IV) = 96] */
+ os_memcpy(J0, nonce, sizeof(nonce));
+ os_memset(J0 + sizeof(nonce), 0, AES_BLOCK_SIZE - sizeof(nonce));
+ J0[AES_BLOCK_SIZE - 1] = 0x01;
+
+ /* 3. C = GCTR_K(inc_32(J_0), P) */
+ inc32(J0);
+ aes_gctr(aes, J0, frame + hdrlen, len - hdrlen, pos);
+ pos += len - hdrlen;
+
+ /*
+ * 4. u = 128 * ceil[len(C)/128] - len(C)
+ * v = 128 * ceil[len(A)/128] - len(A)
+ * 5. S = GHASH_H(A || 0^v || C || 0^u || [len(A)]64 || [len(C)]64)
+ * (i.e., zero padded to block size A || C and lengths of each in bits)
+ */
+ auth = os_malloc(32 + 16 + len - hdrlen + 8 + 8);
+ if (auth == NULL) {
+ os_free(crypt);
+ return NULL;
+ }
+
+ apos = auth;
+
+ /* Zero-padded AAD */
+ os_memcpy(apos, &aad[2], aad_len);
+ apos += aad_len;
+ padlen = (16 - aad_len % 16) % 16;
+ os_memset(apos, 0, padlen);
+ apos += padlen;
+
+ /* Zero-padded C */
+ os_memcpy(apos, crypt + hdrlen + 8, plen);
+ apos += plen;
+ padlen = (16 - plen % 16) % 16;
+ os_memset(apos, 0, padlen);
+ apos += padlen;
+
+ /* Length of AAD and C in bits */
+ WPA_PUT_BE64(apos, aad_len * 8);
+ apos += 8;
+ WPA_PUT_BE64(apos, plen * 8);
+ apos += 8;
+
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP GHASH_H input", auth, apos - auth);
+ ghash(H, auth, apos - auth, S);
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP S = GHASH_H(...)", S, 16);
+ os_free(auth);
+
+ /* 6. T = MSB_t(GCTR_K(J_0, S)) */
+ J0[AES_BLOCK_SIZE - 1] = 0x01;
+ aes_gctr(aes, J0, S, sizeof(S), pos);
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP MIC", pos, 16);
+
+ /* 7. Return (C, T) */
+
+ wpa_hexdump(MSG_EXCESSIVE, "GCMP encrypted", crypt + hdrlen + 8, plen);
+
+ aes_encrypt_deinit(aes);
+
+ *encrypted_len = hdrlen + 8 + plen + 16;
+
+ return crypt;
+}
}
+static void test_vector_gcmp(void)
+{
+ u8 tk[] = { 0xc9, 0x7c, 0x1f, 0x67, 0xce, 0x37, 0x11, 0x85,
+ 0x51, 0x4a, 0x8a, 0x19, 0xf2, 0xbd, 0xd5, 0x2f };
+ u8 pn[] = {
+ 0x00, 0x89, 0x5F, 0x5F, 0x2B, 0x08
+ };
+ u8 frame[] = {
+ 0x88, 0x48, 0x0b, 0x00, 0x0f, 0xd2, 0xe1, 0x28,
+ 0xa5, 0x7c, 0x50, 0x30, 0xf1, 0x84, 0x44, 0x08,
+ 0x50, 0x30, 0xf1, 0x84, 0x44, 0x08, 0x80, 0x33,
+ 0x03, 0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05,
+ 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d,
+ 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
+ 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d,
+ 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25,
+ 0x26, 0x27
+ };
+ u8 *enc, *plain;
+ size_t enc_len, plain_len;
+ u8 fcs[4];
+
+ wpa_printf(MSG_INFO, "\nIEEE P802.11ad/D9.0, M.11.1 GCMP test "
+ "vector #2\n");
+
+ wpa_hexdump(MSG_INFO, "TK", tk, sizeof(tk));
+ wpa_hexdump(MSG_INFO, "PN", pn, sizeof(pn));
+ wpa_hexdump(MSG_INFO, "802.11 Header", frame, 26);
+ wpa_hexdump(MSG_INFO, "Plaintext Data", frame + 26, sizeof(frame) - 26);
+
+ enc = gcmp_encrypt(tk, frame, sizeof(frame), 26, frame + 24, pn, 0,
+ &enc_len);
+ if (enc == NULL) {
+ wpa_printf(MSG_ERROR, "Failed to encrypt GCMP frame");
+ return;
+ }
+
+ wpa_hexdump(MSG_INFO, "Encrypted MPDU (without FCS)", enc, enc_len);
+ WPA_PUT_LE32(fcs, crc32(enc, enc_len));
+ wpa_hexdump(MSG_INFO, "FCS", fcs, sizeof(fcs));
+
+ wpa_debug_level = MSG_INFO;
+ plain = gcmp_decrypt(tk, (const struct ieee80211_hdr *) enc,
+ enc + 26, enc_len - 26, &plain_len);
+ wpa_debug_level = MSG_EXCESSIVE;
+ os_free(enc);
+
+ if (plain == NULL) {
+ wpa_printf(MSG_ERROR, "Failed to decrypt GCMP frame");
+ return;
+ }
+
+ if (plain_len != sizeof(frame) - 26 ||
+ os_memcmp(plain, frame + 26, plain_len) != 0) {
+ wpa_hexdump(MSG_ERROR, "Decryption result did not match",
+ plain, plain_len);
+ }
+
+ os_free(plain);
+}
+
+
int main(int argc, char *argv[])
{
wpa_debug_level = MSG_EXCESSIVE;
test_vector_ccmp();
test_vector_bip();
test_vector_ccmp_mgmt();
+ test_vector_gcmp();
os_program_deinit();
projects / thirdparty / hostap.git / commitdiff
