crypto: update FT derivation functions to use sha384

FILS-FT requires the SHA384 KDF to derive the FT keys
This commit is contained in:
James Prestwood 2019-05-10 13:19:28 -07:00 committed by Denis Kenzior
parent aafb3fa7ed
commit bc381bd8c3
3 changed files with 64 additions and 43 deletions

View File

@ -840,17 +840,18 @@ bool crypto_derive_pmk_r0(const uint8_t *xxkey, size_t xxkey_len,
const uint8_t *ssid, size_t ssid_len, const uint8_t *ssid, size_t ssid_len,
uint16_t mdid, uint16_t mdid,
const uint8_t *r0khid, size_t r0kh_len, const uint8_t *r0khid, size_t r0kh_len,
const uint8_t *s0khid, uint8_t *out_pmk_r0, const uint8_t *s0khid, bool sha384,
uint8_t *out_pmk_r0_name) uint8_t *out_pmk_r0, uint8_t *out_pmk_r0_name)
{ {
uint8_t context[512]; uint8_t context[512];
size_t pos = 0; size_t pos = 0;
uint8_t output[48]; uint8_t output[64];
struct l_checksum *sha256; size_t offset = sha384 ? 48 : 32;
struct l_checksum *sha;
bool r = false; bool r = false;
struct iovec iov[2] = { struct iovec iov[2] = {
[0] = { .iov_base = "FT-R0N", .iov_len = 6 }, [0] = { .iov_base = "FT-R0N", .iov_len = 6 },
[1] = { .iov_base = output + 32, .iov_len = 16 }, [1] = { .iov_base = output + offset, .iov_len = 16 },
}; };
context[pos++] = ssid_len; context[pos++] = ssid_len;
@ -869,25 +870,32 @@ bool crypto_derive_pmk_r0(const uint8_t *xxkey, size_t xxkey_len,
memcpy(context + pos, s0khid, ETH_ALEN); memcpy(context + pos, s0khid, ETH_ALEN);
pos += ETH_ALEN; pos += ETH_ALEN;
if (!kdf_sha256(xxkey, xxkey_len, "FT-R0", 5, context, pos, output, 48)) if (sha384) {
if (!kdf_sha384(xxkey, xxkey_len, "FT-R0", 5, context, pos,
output, 64))
goto exit;
} else {
if (!kdf_sha256(xxkey, xxkey_len, "FT-R0", 5, context, pos,
output, 48))
goto exit;
}
sha = l_checksum_new((sha384) ? L_CHECKSUM_SHA384 : L_CHECKSUM_SHA256);
if (!sha)
goto exit; goto exit;
sha256 = l_checksum_new(L_CHECKSUM_SHA256); l_checksum_updatev(sha, iov, 2);
if (!sha256) l_checksum_get_digest(sha, out_pmk_r0_name, 16);
goto exit;
l_checksum_updatev(sha256, iov, 2); l_checksum_free(sha);
l_checksum_get_digest(sha256, out_pmk_r0_name, 16);
l_checksum_free(sha256); memcpy(out_pmk_r0, output, offset);
memcpy(out_pmk_r0, output, 32);
r = true; r = true;
exit: exit:
explicit_bzero(context, pos); explicit_bzero(context, pos);
explicit_bzero(output, 48); explicit_bzero(output, 64);
return r; return r;
} }
@ -895,12 +903,12 @@ exit:
/* Defined in 802.11-2012, Section 11.6.1.7.4 PMK-R1 */ /* Defined in 802.11-2012, Section 11.6.1.7.4 PMK-R1 */
bool crypto_derive_pmk_r1(const uint8_t *pmk_r0, bool crypto_derive_pmk_r1(const uint8_t *pmk_r0,
const uint8_t *r1khid, const uint8_t *s1khid, const uint8_t *r1khid, const uint8_t *s1khid,
const uint8_t *pmk_r0_name, const uint8_t *pmk_r0_name, bool sha384,
uint8_t *out_pmk_r1, uint8_t *out_pmk_r1,
uint8_t *out_pmk_r1_name) uint8_t *out_pmk_r1_name)
{ {
uint8_t context[2 * ETH_ALEN]; uint8_t context[2 * ETH_ALEN];
struct l_checksum *sha256; struct l_checksum *sha;
bool r = false; bool r = false;
struct iovec iov[3] = { struct iovec iov[3] = {
[0] = { .iov_base = "FT-R1N", .iov_len = 6 }, [0] = { .iov_base = "FT-R1N", .iov_len = 6 },
@ -912,20 +920,26 @@ bool crypto_derive_pmk_r1(const uint8_t *pmk_r0,
memcpy(context + ETH_ALEN, s1khid, ETH_ALEN); memcpy(context + ETH_ALEN, s1khid, ETH_ALEN);
if (!kdf_sha256(pmk_r0, 32, "FT-R1", 5, context, sizeof(context), if (sha384) {
out_pmk_r1, 32)) if (!kdf_sha384(pmk_r0, 48, "FT-R1", 5, context,
goto exit; sizeof(context), out_pmk_r1, 48))
goto exit;
} else {
if (!kdf_sha256(pmk_r0, 32, "FT-R1", 5, context,
sizeof(context), out_pmk_r1, 32))
goto exit;
}
sha256 = l_checksum_new(L_CHECKSUM_SHA256); sha = l_checksum_new((sha384) ? L_CHECKSUM_SHA384 : L_CHECKSUM_SHA256);
if (!sha256) { if (!sha) {
explicit_bzero(out_pmk_r1, 32); explicit_bzero(out_pmk_r1, 48);
goto exit; goto exit;
} }
l_checksum_updatev(sha256, iov, 3); l_checksum_updatev(sha, iov, 3);
l_checksum_get_digest(sha256, out_pmk_r1_name, 16); l_checksum_get_digest(sha, out_pmk_r1_name, 16);
l_checksum_free(sha256); l_checksum_free(sha);
r = true; r = true;
@ -939,11 +953,11 @@ exit:
bool crypto_derive_ft_ptk(const uint8_t *pmk_r1, const uint8_t *pmk_r1_name, bool crypto_derive_ft_ptk(const uint8_t *pmk_r1, const uint8_t *pmk_r1_name,
const uint8_t *addr1, const uint8_t *addr2, const uint8_t *addr1, const uint8_t *addr2,
const uint8_t *nonce1, const uint8_t *nonce2, const uint8_t *nonce1, const uint8_t *nonce2,
uint8_t *out_ptk, size_t ptk_len, bool sha384, uint8_t *out_ptk, size_t ptk_len,
uint8_t *out_ptk_name) uint8_t *out_ptk_name)
{ {
uint8_t context[ETH_ALEN * 2 + 64]; uint8_t context[ETH_ALEN * 2 + 64];
struct l_checksum *sha256; struct l_checksum *sha;
bool r = false; bool r = false;
struct iovec iov[3] = { struct iovec iov[3] = {
[0] = { .iov_base = (uint8_t *) pmk_r1_name, .iov_len = 16 }, [0] = { .iov_base = (uint8_t *) pmk_r1_name, .iov_len = 16 },
@ -959,20 +973,26 @@ bool crypto_derive_ft_ptk(const uint8_t *pmk_r1, const uint8_t *pmk_r1_name,
memcpy(context + 64 + ETH_ALEN, addr2, ETH_ALEN); memcpy(context + 64 + ETH_ALEN, addr2, ETH_ALEN);
if (!kdf_sha256(pmk_r1, 32, "FT-PTK", 6, context, sizeof(context), if (sha384) {
out_ptk, ptk_len)) if (!kdf_sha384(pmk_r1, 48, "FT-PTK", 6, context,
goto exit; sizeof(context), out_ptk, ptk_len))
goto exit;
} else {
if (!kdf_sha256(pmk_r1, 32, "FT-PTK", 6, context,
sizeof(context), out_ptk, ptk_len))
goto exit;
}
sha256 = l_checksum_new(L_CHECKSUM_SHA256); sha = l_checksum_new((sha384) ? L_CHECKSUM_SHA384 : L_CHECKSUM_SHA256);
if (!sha256) { if (!sha) {
explicit_bzero(out_ptk, ptk_len); explicit_bzero(out_ptk, ptk_len);
goto exit; goto exit;
} }
l_checksum_updatev(sha256, iov, 3); l_checksum_updatev(sha, iov, 3);
l_checksum_get_digest(sha256, out_ptk_name, 16); l_checksum_get_digest(sha, out_ptk_name, 16);
l_checksum_free(sha256); l_checksum_free(sha);
r = true; r = true;

View File

@ -120,17 +120,17 @@ bool crypto_derive_pmk_r0(const uint8_t *xxkey, size_t xxkey_len,
const uint8_t *ssid, size_t ssid_len, const uint8_t *ssid, size_t ssid_len,
uint16_t mdid, uint16_t mdid,
const uint8_t *r0khid, size_t r0kh_len, const uint8_t *r0khid, size_t r0kh_len,
const uint8_t *s0khid, uint8_t *out_pmk_r0, const uint8_t *s0khid, bool sha384,
uint8_t *out_pmk_r0_name); uint8_t *out_pmk_r0, uint8_t *out_pmk_r0_name);
bool crypto_derive_pmk_r1(const uint8_t *pmk_r0, bool crypto_derive_pmk_r1(const uint8_t *pmk_r0,
const uint8_t *r1khid, const uint8_t *s1khid, const uint8_t *r1khid, const uint8_t *s1khid,
const uint8_t *pmk_r0_name, const uint8_t *pmk_r0_name, bool sha384,
uint8_t *out_pmk_r1, uint8_t *out_pmk_r1,
uint8_t *out_pmk_r1_name); uint8_t *out_pmk_r1_name);
bool crypto_derive_ft_ptk(const uint8_t *pmk_r1, const uint8_t *pmk_r1_name, bool crypto_derive_ft_ptk(const uint8_t *pmk_r1, const uint8_t *pmk_r1_name,
const uint8_t *addr1, const uint8_t *addr2, const uint8_t *addr1, const uint8_t *addr2,
const uint8_t *nonce1, const uint8_t *nonce2, const uint8_t *nonce1, const uint8_t *nonce2,
uint8_t *out_ptk, size_t ptk_len, bool sha384, uint8_t *out_ptk, size_t ptk_len,
uint8_t *out_ptk_name); uint8_t *out_ptk_name);
bool crypto_derive_pmkid(const uint8_t *pmk, bool crypto_derive_pmkid(const uint8_t *pmk,

View File

@ -434,18 +434,19 @@ bool handshake_state_derive_ptk(struct handshake_state *s)
if (!crypto_derive_pmk_r0(xxkey, 32, s->ssid, s->ssid_len, mdid, if (!crypto_derive_pmk_r0(xxkey, 32, s->ssid, s->ssid_len, mdid,
s->r0khid, s->r0khid_len, s->r0khid, s->r0khid_len,
s->spa, s->spa, false,
s->pmk_r0, s->pmk_r0_name)) s->pmk_r0, s->pmk_r0_name))
return false; return false;
if (!crypto_derive_pmk_r1(s->pmk_r0, s->r1khid, s->spa, if (!crypto_derive_pmk_r1(s->pmk_r0, s->r1khid, s->spa,
s->pmk_r0_name, s->pmk_r0_name, false,
s->pmk_r1, s->pmk_r1_name)) s->pmk_r1, s->pmk_r1_name))
return false; return false;
if (!crypto_derive_ft_ptk(s->pmk_r1, s->pmk_r1_name, s->aa, if (!crypto_derive_ft_ptk(s->pmk_r1, s->pmk_r1_name, s->aa,
s->spa, s->snonce, s->anonce, s->spa, s->snonce, s->anonce,
s->ptk, ptk_size, ptk_name)) false, s->ptk, ptk_size,
ptk_name))
return false; return false;
} else } else
if (!crypto_derive_pairwise_ptk(s->pmk, s->pmk_len, s->spa, if (!crypto_derive_pairwise_ptk(s->pmk, s->pmk_len, s->spa,