This series adds support for the NIST P521 curve to the ecdsa module
to enable signature verification with it.
An issue with the current code in ecdsa is that it assumes that input
arrays providing key coordinates for example, are arrays of digits
(a 'digit' is a 'u64'). This works well for all currently supported
curves, such as NIST P192/256/384, but does not work for NIST P521 where
coordinates are 8 digits + 2 bytes long. So some of the changes deal with
converting byte arrays to digits and adjusting tests on input byte
array lengths to tolerate arrays not providing multiples of 8 bytes.
Regards,
Stefan
v7:
- Applied T-b tag from Christian to all patches
- Applied R-b tag from Jarkko to some patches
- Rephrased some patch descriptions per Jarkko's request
v6:
- Use existing #defines for number of digits rather than plain numbers
(1/13, 6/13) following Bharat's suggestion
- Initialize result from lowest 521 bits of product rather than going
through tmp variable (6/13)
v5:
- Simplified ecc_digits_from_bytes as suggested by Lukas (1/12)
- Using nbits == 521 to detect NIST P521 curve rather than strcmp()
(5,6/12)
- Nits in patch description and comments (11/12)
v4:
- Followed suggestions by Lukas Wummer (1,5,8/12)
- Use nbits rather than ndigits where needed (8/12)
- Renaming 'keylen' variablest to bufsize where necessary (9/12)
- Adjust signature size calculation for NIST P521 (11/12)
v3:
- Dropped ecdh support
- Use ecc_get_curve_nbits for getting number of bits in NIST P521 curve
in ecc_point_mult (7/10)
v2:
- Reformulated some patch descriptions
- Fixed issue detected by krobot
- Some other small changes to the code
Stefan Berger (13):
crypto: ecc - Use ECC_CURVE_NIST_P192/256/384_DIGITS where possible
crypto: ecdsa - Convert byte arrays with key coordinates to digits
crypto: ecdsa - Adjust tests on length of key parameters
crypto: ecdsa - Extend res.x mod n calculation for NIST P521
crypto: ecc - Add nbits field to ecc_curve structure
crypto: ecc - Implement vli_mmod_fast_521 for NIST p521
crypto: ecc - Add special case for NIST P521 in ecc_point_mult
crypto: ecc - Add NIST P521 curve parameters
crypto: ecdsa - Replace ndigits with nbits where precision is needed
crypto: ecdsa - Rename keylen to bufsize where necessary
crypto: ecdsa - Register NIST P521 and extend test suite
crypto: asymmetric_keys - Adjust signature size calculation for NIST
P521
crypto: x509 - Add OID for NIST P521 and extend parser for it
crypto/asymmetric_keys/public_key.c | 14 ++-
crypto/asymmetric_keys/x509_cert_parser.c | 3 +
crypto/ecc.c | 44 +++++--
crypto/ecc_curve_defs.h | 49 ++++++++
crypto/ecdsa.c | 62 ++++++---
crypto/ecrdsa_defs.h | 5 +
crypto/testmgr.c | 7 ++
crypto/testmgr.h | 146 ++++++++++++++++++++++
include/crypto/ecc_curve.h | 2 +
include/crypto/ecdh.h | 1 +
include/crypto/internal/ecc.h | 24 +++-
include/linux/oid_registry.h | 1 +
12 files changed, 335 insertions(+), 23 deletions(-)
--
2.43.0
res.x has been calculated by ecc_point_mult_shamir, which uses
'mod curve_prime' on res.x and therefore p > res.x with 'p' being the
curve_prime. Further, it is true that for the NIST curves p > n with 'n'
being the 'curve_order' and therefore the following may be true as well:
p > res.x >= n.
If res.x >= n then res.x mod n can be calculated by iteratively sub-
tracting n from res.x until res.x < n. For NIST P192/256/384 this can be
done in a single subtraction. This can also be done in a single
subtraction for NIST P521.
The mathematical reason why a single subtraction is sufficient is due to
the values of 'p' and 'n' of the NIST curves where the following holds
true:
note: max(res.x) = p - 1
max(res.x) - n < n
p - 1 - n < n
p - 1 < 2n => holds true for the NIST curves
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
---
crypto/ecdsa.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
index 64e1e69d53ba..1814f009f971 100644
--- a/crypto/ecdsa.c
+++ b/crypto/ecdsa.c
@@ -122,7 +122,7 @@ static int _ecdsa_verify(struct ecc_ctx *ctx, const u64 *hash, const u64 *r, con
/* res.x = res.x mod n (if res.x > order) */
if (unlikely(vli_cmp(res.x, curve->n, ndigits) == 1))
- /* faster alternative for NIST p384, p256 & p192 */
+ /* faster alternative for NIST p521, p384, p256 & p192 */
vli_sub(res.x, res.x, curve->n, ndigits);
if (!vli_cmp(res.x, r, ndigits))
--
2.43.0
Add the parameters for the NIST P521 curve and define a new curve ID
for it. Make the curve available in ecc_get_curve.
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
Reviewed-by: Jarkko Sakkinen <[email protected]>
---
crypto/ecc.c | 2 ++
crypto/ecc_curve_defs.h | 45 +++++++++++++++++++++++++++++++++++++++++
include/crypto/ecdh.h | 1 +
3 files changed, 48 insertions(+)
diff --git a/crypto/ecc.c b/crypto/ecc.c
index ead40b5ebb46..4f6fa8617308 100644
--- a/crypto/ecc.c
+++ b/crypto/ecc.c
@@ -60,6 +60,8 @@ const struct ecc_curve *ecc_get_curve(unsigned int curve_id)
return &nist_p256;
case ECC_CURVE_NIST_P384:
return &nist_p384;
+ case ECC_CURVE_NIST_P521:
+ return &nist_p521;
default:
return NULL;
}
diff --git a/crypto/ecc_curve_defs.h b/crypto/ecc_curve_defs.h
index ab1ef3d94be5..0ecade7d02f5 100644
--- a/crypto/ecc_curve_defs.h
+++ b/crypto/ecc_curve_defs.h
@@ -89,6 +89,51 @@ static struct ecc_curve nist_p384 = {
.b = nist_p384_b
};
+/* NIST P-521 */
+static u64 nist_p521_g_x[] = { 0xf97e7e31c2e5bd66ull, 0x3348b3c1856a429bull,
+ 0xfe1dc127a2ffa8deull, 0xa14b5e77efe75928ull,
+ 0xf828af606b4d3dbaull, 0x9c648139053fb521ull,
+ 0x9e3ecb662395b442ull, 0x858e06b70404e9cdull,
+ 0xc6ull };
+static u64 nist_p521_g_y[] = { 0x88be94769fd16650ull, 0x353c7086a272c240ull,
+ 0xc550b9013fad0761ull, 0x97ee72995ef42640ull,
+ 0x17afbd17273e662cull, 0x98f54449579b4468ull,
+ 0x5c8a5fb42c7d1bd9ull, 0x39296a789a3bc004ull,
+ 0x118ull };
+static u64 nist_p521_p[] = { 0xffffffffffffffffull, 0xffffffffffffffffull,
+ 0xffffffffffffffffull, 0xffffffffffffffffull,
+ 0xffffffffffffffffull, 0xffffffffffffffffull,
+ 0xffffffffffffffffull, 0xffffffffffffffffull,
+ 0x1ffull };
+static u64 nist_p521_n[] = { 0xbb6fb71e91386409ull, 0x3bb5c9b8899c47aeull,
+ 0x7fcc0148f709a5d0ull, 0x51868783bf2f966bull,
+ 0xfffffffffffffffaull, 0xffffffffffffffffull,
+ 0xffffffffffffffffull, 0xffffffffffffffffull,
+ 0x1ffull };
+static u64 nist_p521_a[] = { 0xfffffffffffffffcull, 0xffffffffffffffffull,
+ 0xffffffffffffffffull, 0xffffffffffffffffull,
+ 0xffffffffffffffffull, 0xffffffffffffffffull,
+ 0xffffffffffffffffull, 0xffffffffffffffffull,
+ 0x1ffull };
+static u64 nist_p521_b[] = { 0xef451fd46b503f00ull, 0x3573df883d2c34f1ull,
+ 0x1652c0bd3bb1bf07ull, 0x56193951ec7e937bull,
+ 0xb8b489918ef109e1ull, 0xa2da725b99b315f3ull,
+ 0x929a21a0b68540eeull, 0x953eb9618e1c9a1full,
+ 0x051ull };
+static struct ecc_curve nist_p521 = {
+ .name = "nist_521",
+ .nbits = 521,
+ .g = {
+ .x = nist_p521_g_x,
+ .y = nist_p521_g_y,
+ .ndigits = 9,
+ },
+ .p = nist_p521_p,
+ .n = nist_p521_n,
+ .a = nist_p521_a,
+ .b = nist_p521_b
+};
+
/* curve25519 */
static u64 curve25519_g_x[] = { 0x0000000000000009, 0x0000000000000000,
0x0000000000000000, 0x0000000000000000 };
diff --git a/include/crypto/ecdh.h b/include/crypto/ecdh.h
index a9f98078d29c..9784ecdd2fb4 100644
--- a/include/crypto/ecdh.h
+++ b/include/crypto/ecdh.h
@@ -26,6 +26,7 @@
#define ECC_CURVE_NIST_P192 0x0001
#define ECC_CURVE_NIST_P256 0x0002
#define ECC_CURVE_NIST_P384 0x0003
+#define ECC_CURVE_NIST_P521 0x0004
/**
* struct ecdh - define an ECDH private key
--
2.43.0
In cases where 'keylen' was referring to the size of the buffer used by
a curve's digits, it does not reflect the purpose of the variable anymore
once NIST P521 is used. What it refers to then is the size of the buffer,
which may be a few bytes larger than the size a coordinate of a key.
Therefore, rename keylen to bufsize where appropriate.
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
---
crypto/ecdsa.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
index 4daefb40c37a..4e847b59622a 100644
--- a/crypto/ecdsa.c
+++ b/crypto/ecdsa.c
@@ -35,8 +35,8 @@ struct ecdsa_signature_ctx {
static int ecdsa_get_signature_rs(u64 *dest, size_t hdrlen, unsigned char tag,
const void *value, size_t vlen, unsigned int ndigits)
{
- size_t keylen = ndigits * sizeof(u64);
- ssize_t diff = vlen - keylen;
+ size_t bufsize = ndigits * sizeof(u64);
+ ssize_t diff = vlen - bufsize;
const char *d = value;
u8 rs[ECC_MAX_BYTES];
@@ -58,7 +58,7 @@ static int ecdsa_get_signature_rs(u64 *dest, size_t hdrlen, unsigned char tag,
if (diff)
return -EINVAL;
}
- if (-diff >= keylen)
+ if (-diff >= bufsize)
return -EINVAL;
if (diff) {
@@ -138,7 +138,7 @@ static int ecdsa_verify(struct akcipher_request *req)
{
struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm);
- size_t keylen = ctx->curve->g.ndigits * sizeof(u64);
+ size_t bufsize = ctx->curve->g.ndigits * sizeof(u64);
struct ecdsa_signature_ctx sig_ctx = {
.curve = ctx->curve,
};
@@ -165,14 +165,14 @@ static int ecdsa_verify(struct akcipher_request *req)
goto error;
/* if the hash is shorter then we will add leading zeros to fit to ndigits */
- diff = keylen - req->dst_len;
+ diff = bufsize - req->dst_len;
if (diff >= 0) {
if (diff)
memset(rawhash, 0, diff);
memcpy(&rawhash[diff], buffer + req->src_len, req->dst_len);
} else if (diff < 0) {
/* given hash is longer, we take the left-most bytes */
- memcpy(&rawhash, buffer + req->src_len, keylen);
+ memcpy(&rawhash, buffer + req->src_len, bufsize);
}
ecc_swap_digits((u64 *)rawhash, hash, ctx->curve->g.ndigits);
--
2.43.0
Replace the usage of ndigits with nbits where precise space calculations
are needed, such as in ecdsa_max_size where the length of a coordinate is
determined.
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
---
crypto/ecdsa.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
index 1814f009f971..4daefb40c37a 100644
--- a/crypto/ecdsa.c
+++ b/crypto/ecdsa.c
@@ -266,7 +266,7 @@ static unsigned int ecdsa_max_size(struct crypto_akcipher *tfm)
{
struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm);
- return ctx->pub_key.ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+ return DIV_ROUND_UP(ctx->curve->nbits, 8);
}
static int ecdsa_nist_p384_init_tfm(struct crypto_akcipher *tfm)
--
2.43.0
In preparation for support of NIST P521, adjust the basic tests on the
length of the provided key parameters to only ensure that the length of the
x plus y coordinates parameter array is not an odd number and that each
coordinate fits into an array of 'ndigits' digits. Mathematical tests on
the key's parameters are then done in ecc_is_pubkey_valid_full rejecting
invalid keys.
The change is necessary since NIST P521 keys do not have keys with
coordinates that each require 'full' digits (= all bits in u64 used).
NIST P521 only requires 2 bytes (9 bits) in the most significant digit
unlike NIST P192/256/384 that each require multiple 'full' digits.
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
---
crypto/ecdsa.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
index 6653dec17327..64e1e69d53ba 100644
--- a/crypto/ecdsa.c
+++ b/crypto/ecdsa.c
@@ -230,7 +230,7 @@ static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsig
if (ret < 0)
return ret;
- if (keylen < 1 || (((keylen - 1) >> 1) % sizeof(u64)) != 0)
+ if (keylen < 1 || ((keylen - 1) & 1) != 0)
return -EINVAL;
/* we only accept uncompressed format indicated by '4' */
if (d[0] != 4)
--
2.43.0
In ecc_point_mult use the number of bits of the NIST P521 curve + 2. The
change is required specifically for NIST P521 to pass mathematical tests
on the public key.
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
Reviewed-by: Jarkko Sakkinen <[email protected]>
---
crypto/ecc.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/crypto/ecc.c b/crypto/ecc.c
index 99d41887c005..ead40b5ebb46 100644
--- a/crypto/ecc.c
+++ b/crypto/ecc.c
@@ -1320,7 +1320,10 @@ static void ecc_point_mult(struct ecc_point *result,
carry = vli_add(sk[0], scalar, curve->n, ndigits);
vli_add(sk[1], sk[0], curve->n, ndigits);
scalar = sk[!carry];
- num_bits = sizeof(u64) * ndigits * 8 + 1;
+ if (curve->nbits == 521) /* NIST P521 */
+ num_bits = curve->nbits + 2;
+ else
+ num_bits = sizeof(u64) * ndigits * 8 + 1;
vli_set(rx[1], point->x, ndigits);
vli_set(ry[1], point->y, ndigits);
--
2.43.0
Adjust the calculation of the maximum signature size for support of
NIST P521. While existing curves may prepend a 0 byte to their coordinates
(to make the number positive), NIST P521 will not do this since only the
first bit in the most significant byte is used.
If the encoding of the x & y coordinates requires at least 128 bytes then
an additional byte is needed for the encoding of the length. Take this into
account when calculating the maximum signature size.
Signed-off-by: Stefan Berger <[email protected]>
Reviewed-by: Lukas Wunner <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
---
crypto/asymmetric_keys/public_key.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index e5f22691febd..16cc0be28929 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -233,6 +233,7 @@ static int software_key_query(const struct kernel_pkey_params *params,
info->key_size = len * 8;
if (strncmp(pkey->pkey_algo, "ecdsa", 5) == 0) {
+ int slen = len;
/*
* ECDSA key sizes are much smaller than RSA, and thus could
* operate on (hashed) inputs that are larger than key size.
@@ -246,8 +247,19 @@ static int software_key_query(const struct kernel_pkey_params *params,
* Verify takes ECDSA-Sig (described in RFC 5480) as input,
* which is actually 2 'key_size'-bit integers encoded in
* ASN.1. Account for the ASN.1 encoding overhead here.
+ *
+ * NIST P192/256/384 may prepend a '0' to a coordinate to
+ * indicate a positive integer. NIST P521 never needs it.
*/
- info->max_sig_size = 2 * (len + 3) + 2;
+ if (strcmp(pkey->pkey_algo, "ecdsa-nist-p521") != 0)
+ slen += 1;
+ /* Length of encoding the x & y coordinates */
+ slen = 2 * (slen + 2);
+ /*
+ * If coordinate encoding takes at least 128 bytes then an
+ * additional byte for length encoding is needed.
+ */
+ info->max_sig_size = 1 + (slen >= 128) + 1 + slen;
} else {
info->max_data_size = len;
info->max_sig_size = len;
--
2.43.0
For NIST P192/256/384 the public key's x and y parameters could be copied
directly from a given array since both parameters filled 'ndigits' of
digits (a 'digit' is a u64). For support of NIST P521 the key parameters
need to have leading zeros prepended to the most significant digit since
only 2 bytes of the most significant digit are provided.
Therefore, implement ecc_digits_from_bytes to convert a byte array into an
array of digits and use this function in ecdsa_set_pub_key where an input
byte array needs to be converted into digits.
Suggested-by: Lukas Wunner <[email protected]>
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
---
crypto/ecdsa.c | 14 +++++++++-----
include/crypto/internal/ecc.h | 21 +++++++++++++++++++++
2 files changed, 30 insertions(+), 5 deletions(-)
diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
index fbd76498aba8..6653dec17327 100644
--- a/crypto/ecdsa.c
+++ b/crypto/ecdsa.c
@@ -222,9 +222,8 @@ static int ecdsa_ecc_ctx_reset(struct ecc_ctx *ctx)
static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsigned int keylen)
{
struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm);
+ unsigned int digitlen, ndigits;
const unsigned char *d = key;
- const u64 *digits = (const u64 *)&d[1];
- unsigned int ndigits;
int ret;
ret = ecdsa_ecc_ctx_reset(ctx);
@@ -238,12 +237,17 @@ static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsig
return -EINVAL;
keylen--;
- ndigits = (keylen >> 1) / sizeof(u64);
+ digitlen = keylen >> 1;
+
+ ndigits = DIV_ROUND_UP(digitlen, sizeof(u64));
if (ndigits != ctx->curve->g.ndigits)
return -EINVAL;
- ecc_swap_digits(digits, ctx->pub_key.x, ndigits);
- ecc_swap_digits(&digits[ndigits], ctx->pub_key.y, ndigits);
+ d++;
+
+ ecc_digits_from_bytes(d, digitlen, ctx->pub_key.x, ndigits);
+ ecc_digits_from_bytes(&d[digitlen], digitlen, ctx->pub_key.y, ndigits);
+
ret = ecc_is_pubkey_valid_full(ctx->curve, &ctx->pub_key);
ctx->pub_key_set = ret == 0;
diff --git a/include/crypto/internal/ecc.h b/include/crypto/internal/ecc.h
index 4f6c1a68882f..ab722a8986b7 100644
--- a/include/crypto/internal/ecc.h
+++ b/include/crypto/internal/ecc.h
@@ -56,6 +56,27 @@ static inline void ecc_swap_digits(const void *in, u64 *out, unsigned int ndigit
out[i] = get_unaligned_be64(&src[ndigits - 1 - i]);
}
+/**
+ * ecc_digits_from_bytes() - Create ndigits-sized digits array from byte array
+ * @in: Input byte array
+ * @nbytes Size of input byte array
+ * @out Output digits array
+ * @ndigits: Number of digits to create from byte array
+ */
+static inline void ecc_digits_from_bytes(const u8 *in, unsigned int nbytes,
+ u64 *out, unsigned int ndigits)
+{
+ unsigned int o = nbytes & 7;
+ __be64 msd = 0;
+
+ if (o) {
+ memcpy((u8 *)&msd + sizeof(msd) - o, in, o);
+ out[--ndigits] = be64_to_cpu(msd);
+ in += o;
+ }
+ ecc_swap_digits(in, out, ndigits);
+}
+
/**
* ecc_is_key_valid() - Validate a given ECDH private key
*
--
2.43.0
Replace hard-coded numbers with ECC_CURVE_NIST_P192/256/384_DIGITS where
possible.
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
Reviewed-by: Jarkko Sakkinen <[email protected]>
---
crypto/ecc.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/crypto/ecc.c b/crypto/ecc.c
index f53fb4d6af99..415a2f4e7291 100644
--- a/crypto/ecc.c
+++ b/crypto/ecc.c
@@ -689,7 +689,7 @@ static void vli_mmod_barrett(u64 *result, u64 *product, const u64 *mod,
static void vli_mmod_fast_192(u64 *result, const u64 *product,
const u64 *curve_prime, u64 *tmp)
{
- const unsigned int ndigits = 3;
+ const unsigned int ndigits = ECC_CURVE_NIST_P192_DIGITS;
int carry;
vli_set(result, product, ndigits);
@@ -717,7 +717,7 @@ static void vli_mmod_fast_256(u64 *result, const u64 *product,
const u64 *curve_prime, u64 *tmp)
{
int carry;
- const unsigned int ndigits = 4;
+ const unsigned int ndigits = ECC_CURVE_NIST_P256_DIGITS;
/* t */
vli_set(result, product, ndigits);
@@ -800,7 +800,7 @@ static void vli_mmod_fast_384(u64 *result, const u64 *product,
const u64 *curve_prime, u64 *tmp)
{
int carry;
- const unsigned int ndigits = 6;
+ const unsigned int ndigits = ECC_CURVE_NIST_P384_DIGITS;
/* t */
vli_set(result, product, ndigits);
@@ -932,13 +932,13 @@ static bool vli_mmod_fast(u64 *result, u64 *product,
}
switch (ndigits) {
- case 3:
+ case ECC_CURVE_NIST_P192_DIGITS:
vli_mmod_fast_192(result, product, curve_prime, tmp);
break;
- case 4:
+ case ECC_CURVE_NIST_P256_DIGITS:
vli_mmod_fast_256(result, product, curve_prime, tmp);
break;
- case 6:
+ case ECC_CURVE_NIST_P384_DIGITS:
vli_mmod_fast_384(result, product, curve_prime, tmp);
break;
default:
--
2.43.0
Implement vli_mmod_fast_521 following the description for how to calculate
the modulus for NIST P521 in the NIST publication "Recommendations for
Discrete Logarithm-Based Cryptography: Elliptic Curve Domain Parameters"
section G.1.4.
NIST p521 requires 9 64bit digits, so increase the ECC_MAX_DIGITS so that
the vli digit array provides enough elements to fit the larger integers
required by this curve.
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
---
crypto/ecc.c | 25 +++++++++++++++++++++++++
include/crypto/internal/ecc.h | 3 ++-
2 files changed, 27 insertions(+), 1 deletion(-)
diff --git a/crypto/ecc.c b/crypto/ecc.c
index 415a2f4e7291..99d41887c005 100644
--- a/crypto/ecc.c
+++ b/crypto/ecc.c
@@ -902,6 +902,28 @@ static void vli_mmod_fast_384(u64 *result, const u64 *product,
#undef AND64H
#undef AND64L
+/*
+ * Computes result = product % curve_prime
+ * from "Recommendations for Discrete Logarithm-Based Cryptography:
+ * Elliptic Curve Domain Parameters" section G.1.4
+ */
+static void vli_mmod_fast_521(u64 *result, const u64 *product,
+ const u64 *curve_prime, u64 *tmp)
+{
+ const unsigned int ndigits = ECC_CURVE_NIST_P521_DIGITS;
+ size_t i;
+
+ /* Initialize result with lowest 521 bits from product */
+ vli_set(result, product, ndigits);
+ result[8] &= 0x1ff;
+
+ for (i = 0; i < ndigits; i++)
+ tmp[i] = (product[8 + i] >> 9) | (product[9 + i] << 55);
+ tmp[8] &= 0x1ff;
+
+ vli_mod_add(result, result, tmp, curve_prime, ndigits);
+}
+
/* Computes result = product % curve_prime for different curve_primes.
*
* Note that curve_primes are distinguished just by heuristic check and
@@ -941,6 +963,9 @@ static bool vli_mmod_fast(u64 *result, u64 *product,
case ECC_CURVE_NIST_P384_DIGITS:
vli_mmod_fast_384(result, product, curve_prime, tmp);
break;
+ case ECC_CURVE_NIST_P521_DIGITS:
+ vli_mmod_fast_521(result, product, curve_prime, tmp);
+ break;
default:
pr_err_ratelimited("ecc: unsupported digits size!\n");
return false;
diff --git a/include/crypto/internal/ecc.h b/include/crypto/internal/ecc.h
index ab722a8986b7..4e2f5f938e91 100644
--- a/include/crypto/internal/ecc.h
+++ b/include/crypto/internal/ecc.h
@@ -33,7 +33,8 @@
#define ECC_CURVE_NIST_P192_DIGITS 3
#define ECC_CURVE_NIST_P256_DIGITS 4
#define ECC_CURVE_NIST_P384_DIGITS 6
-#define ECC_MAX_DIGITS (512 / 64) /* due to ecrdsa */
+#define ECC_CURVE_NIST_P521_DIGITS 9
+#define ECC_MAX_DIGITS DIV_ROUND_UP(521, 64) /* NIST P521 */
#define ECC_DIGITS_TO_BYTES_SHIFT 3
--
2.43.0
Add the number of bits a curve has to the ecc_curve definition to be able
to derive the number of bytes a curve requires for its coordinates from it.
It also allows one to identify a curve by its particular size. Set the
number of bits on all curve definitions.
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
---
crypto/ecc_curve_defs.h | 4 ++++
crypto/ecrdsa_defs.h | 5 +++++
include/crypto/ecc_curve.h | 2 ++
3 files changed, 11 insertions(+)
diff --git a/crypto/ecc_curve_defs.h b/crypto/ecc_curve_defs.h
index 9719934c9428..ab1ef3d94be5 100644
--- a/crypto/ecc_curve_defs.h
+++ b/crypto/ecc_curve_defs.h
@@ -17,6 +17,7 @@ static u64 nist_p192_b[] = { 0xFEB8DEECC146B9B1ull, 0x0FA7E9AB72243049ull,
0x64210519E59C80E7ull };
static struct ecc_curve nist_p192 = {
.name = "nist_192",
+ .nbits = 192,
.g = {
.x = nist_p192_g_x,
.y = nist_p192_g_y,
@@ -43,6 +44,7 @@ static u64 nist_p256_b[] = { 0x3BCE3C3E27D2604Bull, 0x651D06B0CC53B0F6ull,
0xB3EBBD55769886BCull, 0x5AC635D8AA3A93E7ull };
static struct ecc_curve nist_p256 = {
.name = "nist_256",
+ .nbits = 256,
.g = {
.x = nist_p256_g_x,
.y = nist_p256_g_y,
@@ -75,6 +77,7 @@ static u64 nist_p384_b[] = { 0x2a85c8edd3ec2aefull, 0xc656398d8a2ed19dull,
0x988e056be3f82d19ull, 0xb3312fa7e23ee7e4ull };
static struct ecc_curve nist_p384 = {
.name = "nist_384",
+ .nbits = 384,
.g = {
.x = nist_p384_g_x,
.y = nist_p384_g_y,
@@ -95,6 +98,7 @@ static u64 curve25519_a[] = { 0x000000000001DB41, 0x0000000000000000,
0x0000000000000000, 0x0000000000000000 };
static const struct ecc_curve ecc_25519 = {
.name = "curve25519",
+ .nbits = 255,
.g = {
.x = curve25519_g_x,
.ndigits = 4,
diff --git a/crypto/ecrdsa_defs.h b/crypto/ecrdsa_defs.h
index 0056335b9d03..1c2c2449e331 100644
--- a/crypto/ecrdsa_defs.h
+++ b/crypto/ecrdsa_defs.h
@@ -47,6 +47,7 @@ static u64 cp256a_b[] = {
static struct ecc_curve gost_cp256a = {
.name = "cp256a",
+ .nbits = 256,
.g = {
.x = cp256a_g_x,
.y = cp256a_g_y,
@@ -80,6 +81,7 @@ static u64 cp256b_b[] = {
static struct ecc_curve gost_cp256b = {
.name = "cp256b",
+ .nbits = 256,
.g = {
.x = cp256b_g_x,
.y = cp256b_g_y,
@@ -117,6 +119,7 @@ static u64 cp256c_b[] = {
static struct ecc_curve gost_cp256c = {
.name = "cp256c",
+ .nbits = 256,
.g = {
.x = cp256c_g_x,
.y = cp256c_g_y,
@@ -166,6 +169,7 @@ static u64 tc512a_b[] = {
static struct ecc_curve gost_tc512a = {
.name = "tc512a",
+ .nbits = 512,
.g = {
.x = tc512a_g_x,
.y = tc512a_g_y,
@@ -211,6 +215,7 @@ static u64 tc512b_b[] = {
static struct ecc_curve gost_tc512b = {
.name = "tc512b",
+ .nbits = 512,
.g = {
.x = tc512b_g_x,
.y = tc512b_g_y,
diff --git a/include/crypto/ecc_curve.h b/include/crypto/ecc_curve.h
index 70964781eb68..63d5754e7614 100644
--- a/include/crypto/ecc_curve.h
+++ b/include/crypto/ecc_curve.h
@@ -23,6 +23,7 @@ struct ecc_point {
* struct ecc_curve - definition of elliptic curve
*
* @name: Short name of the curve.
+ * @nbits: The number of bits of a curve.
* @g: Generator point of the curve.
* @p: Prime number, if Barrett's reduction is used for this curve
* pre-calculated value 'mu' is appended to the @p after ndigits.
@@ -34,6 +35,7 @@ struct ecc_point {
*/
struct ecc_curve {
char *name;
+ unsigned int nbits;
struct ecc_point g;
u64 *p;
u64 *n;
--
2.43.0
Register NIST P521 as an akcipher and extend the testmgr with
NIST P521-specific test vectors.
Signed-off-by: Stefan Berger <[email protected]>
Tested-by: Lukas Wunner <[email protected]>
Reviewed-by: Jarkko Sakkinen <[email protected]>
---
crypto/ecdsa.c | 30 ++++++++++
crypto/testmgr.c | 7 +++
crypto/testmgr.h | 146 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 183 insertions(+)
diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
index 4e847b59622a..894599f1885f 100644
--- a/crypto/ecdsa.c
+++ b/crypto/ecdsa.c
@@ -269,6 +269,28 @@ static unsigned int ecdsa_max_size(struct crypto_akcipher *tfm)
return DIV_ROUND_UP(ctx->curve->nbits, 8);
}
+static int ecdsa_nist_p521_init_tfm(struct crypto_akcipher *tfm)
+{
+ struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm);
+
+ return ecdsa_ecc_ctx_init(ctx, ECC_CURVE_NIST_P521);
+}
+
+static struct akcipher_alg ecdsa_nist_p521 = {
+ .verify = ecdsa_verify,
+ .set_pub_key = ecdsa_set_pub_key,
+ .max_size = ecdsa_max_size,
+ .init = ecdsa_nist_p521_init_tfm,
+ .exit = ecdsa_exit_tfm,
+ .base = {
+ .cra_name = "ecdsa-nist-p521",
+ .cra_driver_name = "ecdsa-nist-p521-generic",
+ .cra_priority = 100,
+ .cra_module = THIS_MODULE,
+ .cra_ctxsize = sizeof(struct ecc_ctx),
+ },
+};
+
static int ecdsa_nist_p384_init_tfm(struct crypto_akcipher *tfm)
{
struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm);
@@ -352,8 +374,15 @@ static int __init ecdsa_init(void)
if (ret)
goto nist_p384_error;
+ ret = crypto_register_akcipher(&ecdsa_nist_p521);
+ if (ret)
+ goto nist_p521_error;
+
return 0;
+nist_p521_error:
+ crypto_unregister_akcipher(&ecdsa_nist_p384);
+
nist_p384_error:
crypto_unregister_akcipher(&ecdsa_nist_p256);
@@ -369,6 +398,7 @@ static void __exit ecdsa_exit(void)
crypto_unregister_akcipher(&ecdsa_nist_p192);
crypto_unregister_akcipher(&ecdsa_nist_p256);
crypto_unregister_akcipher(&ecdsa_nist_p384);
+ crypto_unregister_akcipher(&ecdsa_nist_p521);
}
subsys_initcall(ecdsa_init);
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index c26aeda85787..a017b4ad119b 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -5097,6 +5097,13 @@ static const struct alg_test_desc alg_test_descs[] = {
.suite = {
.akcipher = __VECS(ecdsa_nist_p384_tv_template)
}
+ }, {
+ .alg = "ecdsa-nist-p521",
+ .test = alg_test_akcipher,
+ .fips_allowed = 1,
+ .suite = {
+ .akcipher = __VECS(ecdsa_nist_p521_tv_template)
+ }
}, {
.alg = "ecrdsa",
.test = alg_test_akcipher,
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index 986f331a5fc2..9bde04be8df9 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -991,6 +991,152 @@ static const struct akcipher_testvec ecdsa_nist_p384_tv_template[] = {
},
};
+static const struct akcipher_testvec ecdsa_nist_p521_tv_template[] = {
+ {
+ .key = /* secp521r1(sha224) */
+ "\x04\x01\x4f\x43\x18\xb6\xa9\xc9\x5d\x68\xd3\xa9\x42\xf8\x98\xc0"
+ "\xd2\xd1\xa9\x50\x3b\xe8\xc4\x40\xe6\x11\x78\x88\x4b\xbd\x76\xa7"
+ "\x9a\xe0\xdd\x31\xa4\x67\x78\x45\x33\x9e\x8c\xd1\xc7\x44\xac\x61"
+ "\x68\xc8\x04\xe7\x5c\x79\xb1\xf1\x41\x0c\x71\xc0\x53\xa8\xbc\xfb"
+ "\xf5\xca\xd4\x01\x40\xfd\xa3\x45\xda\x08\xe0\xb4\xcb\x28\x3b\x0a"
+ "\x02\x35\x5f\x02\x9f\x3f\xcd\xef\x08\x22\x40\x97\x74\x65\xb7\x76"
+ "\x85\xc7\xc0\x5c\xfb\x81\xe1\xa5\xde\x0c\x4e\x8b\x12\x31\xb6\x47"
+ "\xed\x37\x0f\x99\x3f\x26\xba\xa3\x8e\xff\x79\x34\x7c\x3a\xfe\x1f"
+ "\x3b\x83\x82\x2f\x14",
+ .key_len = 133,
+ .params =
+ "\x30\x10\x06\x07\x2a\x86\x48\xce\x3d\x02\x01\x06\x05\x2b\x81\x04"
+ "\x00\x23",
+ .param_len = 18,
+ .m =
+ "\xa2\x3a\x6a\x8c\x7b\x3c\xf2\x51\xf8\xbe\x5f\x4f\x3b\x15\x05\xc4"
+ "\xb5\xbc\x19\xe7\x21\x85\xe9\x23\x06\x33\x62\xfb",
+ .m_size = 28,
+ .algo = OID_id_ecdsa_with_sha224,
+ .c =
+ "\x30\x81\x86\x02\x41\x01\xd6\x43\xe7\xff\x42\xb2\xba\x74\x35\xf6"
+ "\xdc\x6d\x02\x7b\x22\xac\xe2\xef\x07\x92\xee\x60\x94\x06\xf8\x3f"
+ "\x59\x0f\x74\xf0\x3f\xd8\x18\xc6\x37\x8a\xcb\xa7\xd8\x7d\x98\x85"
+ "\x29\x88\xff\x0b\x94\x94\x6c\xa6\x9b\x89\x8b\x1e\xfd\x09\x46\x6b"
+ "\xc7\xaf\x7a\xb9\x19\x0a\x02\x41\x3a\x26\x0d\x55\xcd\x23\x1e\x7d"
+ "\xa0\x5e\xf9\x88\xf3\xd2\x32\x90\x57\x0f\xf8\x65\x97\x6b\x09\x4d"
+ "\x22\x26\x0b\x5f\x49\x32\x6b\x91\x99\x30\x90\x0f\x1c\x8f\x78\xd3"
+ "\x9f\x0e\x64\xcc\xc4\xe8\x43\xd9\x0e\x1c\xad\x22\xda\x82\x00\x35"
+ "\xa3\x50\xb1\xa5\x98\x92\x2a\xa5\x52",
+ .c_size = 137,
+ .public_key_vec = true,
+ .siggen_sigver_test = true,
+ },
+ {
+ .key = /* secp521r1(sha256) */
+ "\x04\x01\x05\x3a\x6b\x3b\x5a\x0f\xa7\xb9\xb7\x32\x53\x4e\xe2\xae"
+ "\x0a\x52\xc5\xda\xdd\x5a\x79\x1c\x30\x2d\x33\x07\x79\xd5\x70\x14"
+ "\x61\x0c\xec\x26\x4d\xd8\x35\x57\x04\x1d\x88\x33\x4d\xce\x05\x36"
+ "\xa5\xaf\x56\x84\xfa\x0b\x9e\xff\x7b\x30\x4b\x92\x1d\x06\xf8\x81"
+ "\x24\x1e\x51\x00\x09\x21\x51\xf7\x46\x0a\x77\xdb\xb5\x0c\xe7\x9c"
+ "\xff\x27\x3c\x02\x71\xd7\x85\x36\xf1\xaa\x11\x59\xd8\xb8\xdc\x09"
+ "\xdc\x6d\x5a\x6f\x63\x07\x6c\xe1\xe5\x4d\x6e\x0f\x6e\xfb\x7c\x05"
+ "\x8a\xe9\x53\xa8\xcf\xce\x43\x0e\x82\x20\x86\xbc\x88\x9c\xb7\xe3"
+ "\xe6\x77\x1e\x1f\x8a",
+ .key_len = 133,
+ .params =
+ "\x30\x10\x06\x07\x2a\x86\x48\xce\x3d\x02\x01\x06\x05\x2b\x81\x04"
+ "\x00\x23",
+ .param_len = 18,
+ .m =
+ "\xcc\x97\x73\x0c\x73\xa2\x53\x2b\xfa\xd7\x83\x1d\x0c\x72\x1b\x39"
+ "\x80\x71\x8d\xdd\xc5\x9b\xff\x55\x32\x98\x25\xa2\x58\x2e\xb7\x73",
+ .m_size = 32,
+ .algo = OID_id_ecdsa_with_sha256,
+ .c =
+ "\x30\x81\x88\x02\x42\x00\xcd\xa5\x5f\x57\x52\x27\x78\x3a\xb5\x06"
+ "\x0f\xfd\x83\xfc\x0e\xd9\xce\x50\x9f\x7d\x1f\xca\x8b\xa8\x2d\x56"
+ "\x3c\xf6\xf0\xd8\xe1\xb7\x5d\x95\x35\x6f\x02\x0e\xaf\xe1\x4c\xae"
+ "\xce\x54\x76\x9a\xc2\x8f\xb8\x38\x1f\x46\x0b\x04\x64\x34\x79\xde"
+ "\x7e\xd7\x59\x10\xe9\xd9\xd5\x02\x42\x01\xcf\x50\x85\x38\xf9\x15"
+ "\x83\x18\x04\x6b\x35\xae\x65\xb5\x99\x12\x0a\xa9\x79\x24\xb9\x37"
+ "\x35\xdd\xa0\xe0\x87\x2c\x44\x4b\x5a\xee\xaf\xfa\x10\xdd\x9b\xfb"
+ "\x36\x1a\x31\x03\x42\x02\x5f\x50\xf0\xa2\x0d\x1c\x57\x56\x8f\x12"
+ "\xb7\x1d\x91\x55\x38\xb6\xf6\x34\x65\xc7\xbd",
+ .c_size = 139,
+ .public_key_vec = true,
+ .siggen_sigver_test = true,
+ },
+ {
+ .key = /* secp521r1(sha384) */
+ "\x04\x00\x2e\xd6\x21\x04\x75\xc3\xdc\x7d\xff\x0e\xf3\x70\x25\x2b"
+ "\xad\x72\xfc\x5a\x91\xf1\xd5\x9c\x64\xf3\x1f\x47\x11\x10\x62\x33"
+ "\xfd\x2e\xe8\x32\xca\x9e\x6f\x0a\x4c\x5b\x35\x9a\x46\xc5\xe7\xd4"
+ "\x38\xda\xb2\xf0\xf4\x87\xf3\x86\xf4\xea\x70\xad\x1e\xd4\x78\x8c"
+ "\x36\x18\x17\x00\xa2\xa0\x34\x1b\x2e\x6a\xdf\x06\xd6\x99\x2d\x47"
+ "\x50\x92\x1a\x8a\x72\x9c\x23\x44\xfa\xa7\xa9\xed\xa6\xef\x26\x14"
+ "\xb3\x9d\xfe\x5e\xa3\x8c\xd8\x29\xf8\xdf\xad\xa6\xab\xfc\xdd\x46"
+ "\x22\x6e\xd7\x35\xc7\x23\xb7\x13\xae\xb6\x34\xff\xd7\x80\xe5\x39"
+ "\xb3\x3b\x5b\x1b\x94",
+ .key_len = 133,
+ .params =
+ "\x30\x10\x06\x07\x2a\x86\x48\xce\x3d\x02\x01\x06\x05\x2b\x81\x04"
+ "\x00\x23",
+ .param_len = 18,
+ .m =
+ "\x36\x98\xd6\x82\xfa\xad\xed\x3c\xb9\x40\xb6\x4d\x9e\xb7\x04\x26"
+ "\xad\x72\x34\x44\xd2\x81\xb4\x9b\xbe\x01\x04\x7a\xd8\x50\xf8\x59"
+ "\xba\xad\x23\x85\x6b\x59\xbe\xfb\xf6\x86\xd4\x67\xa8\x43\x28\x76",
+ .m_size = 48,
+ .algo = OID_id_ecdsa_with_sha384,
+ .c =
+ "\x30\x81\x88\x02\x42\x00\x93\x96\x76\x3c\x27\xea\xaa\x9c\x26\xec"
+ "\x51\xdc\xe8\x35\x5e\xae\x16\xf2\x4b\x64\x98\xf7\xec\xda\xc7\x7e"
+ "\x42\x71\x86\x57\x2d\xf1\x7d\xe4\xdf\x9b\x7d\x9e\x47\xca\x33\x32"
+ "\x76\x06\xd0\xf9\xc0\xe4\xe6\x84\x59\xfd\x1a\xc4\x40\xdd\x43\xb8"
+ "\x6a\xdd\xfb\xe6\x63\x4e\x28\x02\x42\x00\xff\xc3\x6a\x87\x6e\xb5"
+ "\x13\x1f\x20\x55\xce\x37\x97\xc9\x05\x51\xe5\xe4\x3c\xbc\x93\x65"
+ "\x57\x1c\x30\xda\xa7\xcd\x26\x28\x76\x3b\x52\xdf\xc4\xc0\xdb\x54"
+ "\xdb\x8a\x0d\x6a\xc3\xf3\x7a\xd1\xfa\xe7\xa7\xe5\x5a\x94\x56\xcf"
+ "\x8f\xb4\x22\xc6\x4f\xab\x2b\x62\xc1\x42\xb1",
+ .c_size = 139,
+ .public_key_vec = true,
+ .siggen_sigver_test = true,
+ },
+ {
+ .key = /* secp521r1(sha512) */
+ "\x04\x00\xc7\x65\xee\x0b\x86\x7d\x8f\x02\xf1\x74\x5b\xb0\x4c\x3f"
+ "\xa6\x35\x60\x9f\x55\x23\x11\xcc\xdf\xb8\x42\x99\xee\x6c\x96\x6a"
+ "\x27\xa2\x56\xb2\x2b\x03\xad\x0f\xe7\x97\xde\x09\x5d\xb4\xc5\x5f"
+ "\xbd\x87\x37\xbf\x5a\x16\x35\x56\x08\xfd\x6f\x06\x1a\x1c\x84\xee"
+ "\xc3\x64\xb3\x00\x9e\xbd\x6e\x60\x76\xee\x69\xfd\x3a\xb8\xcd\x7e"
+ "\x91\x68\x53\x57\x44\x13\x2e\x77\x09\x2a\xbe\x48\xbd\x91\xd8\xf6"
+ "\x21\x16\x53\x99\xd5\xf0\x40\xad\xa6\xf8\x58\x26\xb6\x9a\xf8\x77"
+ "\xfe\x3a\x05\x1a\xdb\xa9\x0f\xc0\x6c\x76\x30\x8c\xd8\xde\x44\xae"
+ "\xd0\x17\xdf\x49\x6a",
+ .key_len = 133,
+ .params =
+ "\x30\x10\x06\x07\x2a\x86\x48\xce\x3d\x02\x01\x06\x05\x2b\x81\x04"
+ "\x00\x23",
+ .param_len = 18,
+ .m =
+ "\x5c\xa6\xbc\x79\xb8\xa0\x1e\x11\x83\xf7\xe9\x05\xdf\xba\xf7\x69"
+ "\x97\x22\x32\xe4\x94\x7c\x65\xbd\x74\xc6\x9a\x8b\xbd\x0d\xdc\xed"
+ "\xf5\x9c\xeb\xe1\xc5\x68\x40\xf2\xc7\x04\xde\x9e\x0d\x76\xc5\xa3"
+ "\xf9\x3c\x6c\x98\x08\x31\xbd\x39\xe8\x42\x7f\x80\x39\x6f\xfe\x68",
+ .m_size = 64,
+ .algo = OID_id_ecdsa_with_sha512,
+ .c =
+ "\x30\x81\x88\x02\x42\x01\x5c\x71\x86\x96\xac\x21\x33\x7e\x4e\xaa"
+ "\x86\xec\xa8\x05\x03\x52\x56\x63\x0e\x02\xcc\x94\xa9\x05\xb9\xfb"
+ "\x62\x1e\x42\x03\x6c\x74\x8a\x1f\x12\x3e\xb7\x7e\x51\xff\x7f\x27"
+ "\x93\xe8\x6c\x49\x7d\x28\xfc\x80\xa6\x13\xfc\xb6\x90\xf7\xbb\x28"
+ "\xb5\x04\xb0\xb6\x33\x1c\x7e\x02\x42\x01\x70\x43\x52\x1d\xe3\xc6"
+ "\xbd\x5a\x40\x95\x35\x89\x4f\x41\x5f\x9e\x19\x88\x05\x3e\x43\x39"
+ "\x01\xbd\xb7\x7a\x76\x37\x51\x47\x49\x98\x12\x71\xd0\xe9\xca\xa7"
+ "\xc0\xcb\xaa\x00\x55\xbb\x6a\xb4\x73\x00\xd2\x72\x74\x13\x63\x39"
+ "\xa6\xe5\x25\x46\x1e\x77\x44\x78\xe0\xd1\x04",
+ .c_size = 139,
+ .public_key_vec = true,
+ .siggen_sigver_test = true,
+ },
+};
+
/*
* EC-RDSA test vectors are generated by gost-engine.
*/
--
2.43.0
I apologize for the missing part in the title.
Stefan
On 3/20/24 07:47, Stefan Berger wrote:
> This series adds support for the NIST P521 curve to the ecdsa module
> to enable signature verification with it.
>
> An issue with the current code in ecdsa is that it assumes that input
> arrays providing key coordinates for example, are arrays of digits
> (a 'digit' is a 'u64'). This works well for all currently supported
> curves, such as NIST P192/256/384, but does not work for NIST P521 where
> coordinates are 8 digits + 2 bytes long. So some of the changes deal with
> converting byte arrays to digits and adjusting tests on input byte
> array lengths to tolerate arrays not providing multiples of 8 bytes.
>
> Regards,
> Stefan
>
> v7:
> - Applied T-b tag from Christian to all patches
> - Applied R-b tag from Jarkko to some patches
> - Rephrased some patch descriptions per Jarkko's request
>
> v6:
> - Use existing #defines for number of digits rather than plain numbers
> (1/13, 6/13) following Bharat's suggestion
> - Initialize result from lowest 521 bits of product rather than going
> through tmp variable (6/13)
>
> v5:
> - Simplified ecc_digits_from_bytes as suggested by Lukas (1/12)
> - Using nbits == 521 to detect NIST P521 curve rather than strcmp()
> (5,6/12)
> - Nits in patch description and comments (11/12)
>
> v4:
> - Followed suggestions by Lukas Wummer (1,5,8/12)
> - Use nbits rather than ndigits where needed (8/12)
> - Renaming 'keylen' variablest to bufsize where necessary (9/12)
> - Adjust signature size calculation for NIST P521 (11/12)
>
> v3:
> - Dropped ecdh support
> - Use ecc_get_curve_nbits for getting number of bits in NIST P521 curve
> in ecc_point_mult (7/10)
>
> v2:
> - Reformulated some patch descriptions
> - Fixed issue detected by krobot
> - Some other small changes to the code
>
> Stefan Berger (13):
> crypto: ecc - Use ECC_CURVE_NIST_P192/256/384_DIGITS where possible
> crypto: ecdsa - Convert byte arrays with key coordinates to digits
> crypto: ecdsa - Adjust tests on length of key parameters
> crypto: ecdsa - Extend res.x mod n calculation for NIST P521
> crypto: ecc - Add nbits field to ecc_curve structure
> crypto: ecc - Implement vli_mmod_fast_521 for NIST p521
> crypto: ecc - Add special case for NIST P521 in ecc_point_mult
> crypto: ecc - Add NIST P521 curve parameters
> crypto: ecdsa - Replace ndigits with nbits where precision is needed
> crypto: ecdsa - Rename keylen to bufsize where necessary
> crypto: ecdsa - Register NIST P521 and extend test suite
> crypto: asymmetric_keys - Adjust signature size calculation for NIST
> P521
> crypto: x509 - Add OID for NIST P521 and extend parser for it
>
> crypto/asymmetric_keys/public_key.c | 14 ++-
> crypto/asymmetric_keys/x509_cert_parser.c | 3 +
> crypto/ecc.c | 44 +++++--
> crypto/ecc_curve_defs.h | 49 ++++++++
> crypto/ecdsa.c | 62 ++++++---
> crypto/ecrdsa_defs.h | 5 +
> crypto/testmgr.c | 7 ++
> crypto/testmgr.h | 146 ++++++++++++++++++++++
> include/crypto/ecc_curve.h | 2 +
> include/crypto/ecdh.h | 1 +
> include/crypto/internal/ecc.h | 24 +++-
> include/linux/oid_registry.h | 1 +
> 12 files changed, 335 insertions(+), 23 deletions(-)
>
On Wed Mar 20, 2024 at 1:47 PM EET, Stefan Berger wrote:
> For NIST P192/256/384 the public key's x and y parameters could be copied
> directly from a given array since both parameters filled 'ndigits' of
> digits (a 'digit' is a u64). For support of NIST P521 the key parameters
> need to have leading zeros prepended to the most significant digit since
> only 2 bytes of the most significant digit are provided.
>
> Therefore, implement ecc_digits_from_bytes to convert a byte array into an
> array of digits and use this function in ecdsa_set_pub_key where an input
> byte array needs to be converted into digits.
>
> Suggested-by: Lukas Wunner <[email protected]>
> Signed-off-by: Stefan Berger <[email protected]>
> Tested-by: Lukas Wunner <[email protected]>
> ---
> crypto/ecdsa.c | 14 +++++++++-----
> include/crypto/internal/ecc.h | 21 +++++++++++++++++++++
> 2 files changed, 30 insertions(+), 5 deletions(-)
>
> diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
> index fbd76498aba8..6653dec17327 100644
> --- a/crypto/ecdsa.c
> +++ b/crypto/ecdsa.c
> @@ -222,9 +222,8 @@ static int ecdsa_ecc_ctx_reset(struct ecc_ctx *ctx)
> static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsigned int keylen)
> {
> struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm);
> + unsigned int digitlen, ndigits;
> const unsigned char *d = key;
> - const u64 *digits = (const u64 *)&d[1];
> - unsigned int ndigits;
> int ret;
>
> ret = ecdsa_ecc_ctx_reset(ctx);
> @@ -238,12 +237,17 @@ static int ecdsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsig
> return -EINVAL;
>
> keylen--;
> - ndigits = (keylen >> 1) / sizeof(u64);
> + digitlen = keylen >> 1;
> +
> + ndigits = DIV_ROUND_UP(digitlen, sizeof(u64));
> if (ndigits != ctx->curve->g.ndigits)
> return -EINVAL;
>
> - ecc_swap_digits(digits, ctx->pub_key.x, ndigits);
> - ecc_swap_digits(&digits[ndigits], ctx->pub_key.y, ndigits);
> + d++;
> +
> + ecc_digits_from_bytes(d, digitlen, ctx->pub_key.x, ndigits);
> + ecc_digits_from_bytes(&d[digitlen], digitlen, ctx->pub_key.y, ndigits);
> +
> ret = ecc_is_pubkey_valid_full(ctx->curve, &ctx->pub_key);
>
> ctx->pub_key_set = ret == 0;
> diff --git a/include/crypto/internal/ecc.h b/include/crypto/internal/ecc.h
> index 4f6c1a68882f..ab722a8986b7 100644
> --- a/include/crypto/internal/ecc.h
> +++ b/include/crypto/internal/ecc.h
> @@ -56,6 +56,27 @@ static inline void ecc_swap_digits(const void *in, u64 *out, unsigned int ndigit
> out[i] = get_unaligned_be64(&src[ndigits - 1 - i]);
> }
>
> +/**
> + * ecc_digits_from_bytes() - Create ndigits-sized digits array from byte array
> + * @in: Input byte array
> + * @nbytes Size of input byte array
> + * @out Output digits array
> + * @ndigits: Number of digits to create from byte array
> + */
> +static inline void ecc_digits_from_bytes(const u8 *in, unsigned int nbytes,
> + u64 *out, unsigned int ndigits)
> +{
> + unsigned int o = nbytes & 7;
> + __be64 msd = 0;
> +
> + if (o) {
> + memcpy((u8 *)&msd + sizeof(msd) - o, in, o);
> + out[--ndigits] = be64_to_cpu(msd);
> + in += o;
> + }
> + ecc_swap_digits(in, out, ndigits);
> +}
> +
> /**
> * ecc_is_key_valid() - Validate a given ECDH private key
> *
Reviewed-by: Jarkko Sakkinen <[email protected]>
BR, Jarkko
On Wed Mar 20, 2024 at 1:47 PM EET, Stefan Berger wrote:
> res.x has been calculated by ecc_point_mult_shamir, which uses
> 'mod curve_prime' on res.x and therefore p > res.x with 'p' being the
> curve_prime. Further, it is true that for the NIST curves p > n with 'n'
> being the 'curve_order' and therefore the following may be true as well:
> p > res.x >= n.
>
> If res.x >= n then res.x mod n can be calculated by iteratively sub-
> tracting n from res.x until res.x < n. For NIST P192/256/384 this can be
> done in a single subtraction. This can also be done in a single
> subtraction for NIST P521.
>
> The mathematical reason why a single subtraction is sufficient is due to
> the values of 'p' and 'n' of the NIST curves where the following holds
> true:
>
> note: max(res.x) = p - 1
>
> max(res.x) - n < n
> p - 1 - n < n
> p - 1 < 2n => holds true for the NIST curves
>
> Signed-off-by: Stefan Berger <[email protected]>
> Tested-by: Lukas Wunner <[email protected]>
> ---
> crypto/ecdsa.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
> index 64e1e69d53ba..1814f009f971 100644
> --- a/crypto/ecdsa.c
> +++ b/crypto/ecdsa.c
> @@ -122,7 +122,7 @@ static int _ecdsa_verify(struct ecc_ctx *ctx, const u64 *hash, const u64 *r, con
>
> /* res.x = res.x mod n (if res.x > order) */
> if (unlikely(vli_cmp(res.x, curve->n, ndigits) == 1))
> - /* faster alternative for NIST p384, p256 & p192 */
> + /* faster alternative for NIST p521, p384, p256 & p192 */
> vli_sub(res.x, res.x, curve->n, ndigits);
>
> if (!vli_cmp(res.x, r, ndigits))
Reviewed-by: Jarkko Sakkinen <[email protected]>
BR, Jarkko
On Wed Mar 20, 2024 at 1:47 PM EET, Stefan Berger wrote:
> Add the number of bits a curve has to the ecc_curve definition to be able
> to derive the number of bytes a curve requires for its coordinates from it.
> It also allows one to identify a curve by its particular size. Set the
> number of bits on all curve definitions.
>
> Signed-off-by: Stefan Berger <[email protected]>
> Tested-by: Lukas Wunner <[email protected]>
> ---
> crypto/ecc_curve_defs.h | 4 ++++
> crypto/ecrdsa_defs.h | 5 +++++
> include/crypto/ecc_curve.h | 2 ++
> 3 files changed, 11 insertions(+)
>
> diff --git a/crypto/ecc_curve_defs.h b/crypto/ecc_curve_defs.h
> index 9719934c9428..ab1ef3d94be5 100644
> --- a/crypto/ecc_curve_defs.h
> +++ b/crypto/ecc_curve_defs.h
> @@ -17,6 +17,7 @@ static u64 nist_p192_b[] = { 0xFEB8DEECC146B9B1ull, 0x0FA7E9AB72243049ull,
> 0x64210519E59C80E7ull };
> static struct ecc_curve nist_p192 = {
> .name = "nist_192",
> + .nbits = 192,
> .g = {
> .x = nist_p192_g_x,
> .y = nist_p192_g_y,
> @@ -43,6 +44,7 @@ static u64 nist_p256_b[] = { 0x3BCE3C3E27D2604Bull, 0x651D06B0CC53B0F6ull,
> 0xB3EBBD55769886BCull, 0x5AC635D8AA3A93E7ull };
> static struct ecc_curve nist_p256 = {
> .name = "nist_256",
> + .nbits = 256,
> .g = {
> .x = nist_p256_g_x,
> .y = nist_p256_g_y,
> @@ -75,6 +77,7 @@ static u64 nist_p384_b[] = { 0x2a85c8edd3ec2aefull, 0xc656398d8a2ed19dull,
> 0x988e056be3f82d19ull, 0xb3312fa7e23ee7e4ull };
> static struct ecc_curve nist_p384 = {
> .name = "nist_384",
> + .nbits = 384,
> .g = {
> .x = nist_p384_g_x,
> .y = nist_p384_g_y,
> @@ -95,6 +98,7 @@ static u64 curve25519_a[] = { 0x000000000001DB41, 0x0000000000000000,
> 0x0000000000000000, 0x0000000000000000 };
> static const struct ecc_curve ecc_25519 = {
> .name = "curve25519",
> + .nbits = 255,
> .g = {
> .x = curve25519_g_x,
> .ndigits = 4,
> diff --git a/crypto/ecrdsa_defs.h b/crypto/ecrdsa_defs.h
> index 0056335b9d03..1c2c2449e331 100644
> --- a/crypto/ecrdsa_defs.h
> +++ b/crypto/ecrdsa_defs.h
> @@ -47,6 +47,7 @@ static u64 cp256a_b[] = {
>
> static struct ecc_curve gost_cp256a = {
> .name = "cp256a",
> + .nbits = 256,
> .g = {
> .x = cp256a_g_x,
> .y = cp256a_g_y,
> @@ -80,6 +81,7 @@ static u64 cp256b_b[] = {
>
> static struct ecc_curve gost_cp256b = {
> .name = "cp256b",
> + .nbits = 256,
> .g = {
> .x = cp256b_g_x,
> .y = cp256b_g_y,
> @@ -117,6 +119,7 @@ static u64 cp256c_b[] = {
>
> static struct ecc_curve gost_cp256c = {
> .name = "cp256c",
> + .nbits = 256,
> .g = {
> .x = cp256c_g_x,
> .y = cp256c_g_y,
> @@ -166,6 +169,7 @@ static u64 tc512a_b[] = {
>
> static struct ecc_curve gost_tc512a = {
> .name = "tc512a",
> + .nbits = 512,
> .g = {
> .x = tc512a_g_x,
> .y = tc512a_g_y,
> @@ -211,6 +215,7 @@ static u64 tc512b_b[] = {
>
> static struct ecc_curve gost_tc512b = {
> .name = "tc512b",
> + .nbits = 512,
> .g = {
> .x = tc512b_g_x,
> .y = tc512b_g_y,
> diff --git a/include/crypto/ecc_curve.h b/include/crypto/ecc_curve.h
> index 70964781eb68..63d5754e7614 100644
> --- a/include/crypto/ecc_curve.h
> +++ b/include/crypto/ecc_curve.h
> @@ -23,6 +23,7 @@ struct ecc_point {
> * struct ecc_curve - definition of elliptic curve
> *
> * @name: Short name of the curve.
> + * @nbits: The number of bits of a curve.
> * @g: Generator point of the curve.
> * @p: Prime number, if Barrett's reduction is used for this curve
> * pre-calculated value 'mu' is appended to the @p after ndigits.
> @@ -34,6 +35,7 @@ struct ecc_point {
> */
> struct ecc_curve {
> char *name;
> + unsigned int nbits;
Nit:
Hmm not strongly opionated here but wouldn't it be more consistent to
use u32 here as the types below are also exact bitsize types?
> struct ecc_point g;
> u64 *p;
> u64 *n;
BR, Jarkko
On Wed Mar 20, 2024 at 1:47 PM EET, Stefan Berger wrote:
> Implement vli_mmod_fast_521 following the description for how to calculate
> the modulus for NIST P521 in the NIST publication "Recommendations for
> Discrete Logarithm-Based Cryptography: Elliptic Curve Domain Parameters"
> section G.1.4.
>
> NIST p521 requires 9 64bit digits, so increase the ECC_MAX_DIGITS so that
> the vli digit array provides enough elements to fit the larger integers
> required by this curve.
>
> Signed-off-by: Stefan Berger <[email protected]>
> Tested-by: Lukas Wunner <[email protected]>
> ---
> crypto/ecc.c | 25 +++++++++++++++++++++++++
> include/crypto/internal/ecc.h | 3 ++-
> 2 files changed, 27 insertions(+), 1 deletion(-)
>
> diff --git a/crypto/ecc.c b/crypto/ecc.c
> index 415a2f4e7291..99d41887c005 100644
> --- a/crypto/ecc.c
> +++ b/crypto/ecc.c
> @@ -902,6 +902,28 @@ static void vli_mmod_fast_384(u64 *result, const u64 *product,
> #undef AND64H
> #undef AND64L
>
> +/*
> + * Computes result = product % curve_prime
> + * from "Recommendations for Discrete Logarithm-Based Cryptography:
> + * Elliptic Curve Domain Parameters" section G.1.4
> + */
> +static void vli_mmod_fast_521(u64 *result, const u64 *product,
> + const u64 *curve_prime, u64 *tmp)
> +{
> + const unsigned int ndigits = ECC_CURVE_NIST_P521_DIGITS;
> + size_t i;
> +
> + /* Initialize result with lowest 521 bits from product */
> + vli_set(result, product, ndigits);
> + result[8] &= 0x1ff;
> +
> + for (i = 0; i < ndigits; i++)
> + tmp[i] = (product[8 + i] >> 9) | (product[9 + i] << 55);
> + tmp[8] &= 0x1ff;
> +
> + vli_mod_add(result, result, tmp, curve_prime, ndigits);
> +}
> +
> /* Computes result = product % curve_prime for different curve_primes.
> *
> * Note that curve_primes are distinguished just by heuristic check and
> @@ -941,6 +963,9 @@ static bool vli_mmod_fast(u64 *result, u64 *product,
> case ECC_CURVE_NIST_P384_DIGITS:
> vli_mmod_fast_384(result, product, curve_prime, tmp);
> break;
> + case ECC_CURVE_NIST_P521_DIGITS:
> + vli_mmod_fast_521(result, product, curve_prime, tmp);
> + break;
> default:
> pr_err_ratelimited("ecc: unsupported digits size!\n");
> return false;
> diff --git a/include/crypto/internal/ecc.h b/include/crypto/internal/ecc.h
> index ab722a8986b7..4e2f5f938e91 100644
> --- a/include/crypto/internal/ecc.h
> +++ b/include/crypto/internal/ecc.h
> @@ -33,7 +33,8 @@
> #define ECC_CURVE_NIST_P192_DIGITS 3
> #define ECC_CURVE_NIST_P256_DIGITS 4
> #define ECC_CURVE_NIST_P384_DIGITS 6
> -#define ECC_MAX_DIGITS (512 / 64) /* due to ecrdsa */
> +#define ECC_CURVE_NIST_P521_DIGITS 9
> +#define ECC_MAX_DIGITS DIV_ROUND_UP(521, 64) /* NIST P521 */
>
> #define ECC_DIGITS_TO_BYTES_SHIFT 3
>
Reviewed-by: Jarkko Sakkinen <[email protected]>
BR, Jarkko
On Wed Mar 20, 2024 at 1:47 PM EET, Stefan Berger wrote:
> Replace the usage of ndigits with nbits where precise space calculations
> are needed, such as in ecdsa_max_size where the length of a coordinate is
> determined.
>
> Signed-off-by: Stefan Berger <[email protected]>
> Tested-by: Lukas Wunner <[email protected]>
> ---
> crypto/ecdsa.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
> index 1814f009f971..4daefb40c37a 100644
> --- a/crypto/ecdsa.c
> +++ b/crypto/ecdsa.c
> @@ -266,7 +266,7 @@ static unsigned int ecdsa_max_size(struct crypto_akcipher *tfm)
> {
> struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm);
>
> - return ctx->pub_key.ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
> + return DIV_ROUND_UP(ctx->curve->nbits, 8);
> }
>
> static int ecdsa_nist_p384_init_tfm(struct crypto_akcipher *tfm)
Reviewed-by: Jarkko Sakkinen <[email protected]>
BR, Jarkko
On Wed Mar 20, 2024 at 1:47 PM EET, Stefan Berger wrote:
> In cases where 'keylen' was referring to the size of the buffer used by
> a curve's digits, it does not reflect the purpose of the variable anymore
> once NIST P521 is used. What it refers to then is the size of the buffer,
> which may be a few bytes larger than the size a coordinate of a key.
> Therefore, rename keylen to bufsize where appropriate.
>
> Signed-off-by: Stefan Berger <[email protected]>
> Tested-by: Lukas Wunner <[email protected]>
> ---
> crypto/ecdsa.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c
> index 4daefb40c37a..4e847b59622a 100644
> --- a/crypto/ecdsa.c
> +++ b/crypto/ecdsa.c
> @@ -35,8 +35,8 @@ struct ecdsa_signature_ctx {
> static int ecdsa_get_signature_rs(u64 *dest, size_t hdrlen, unsigned char tag,
> const void *value, size_t vlen, unsigned int ndigits)
> {
> - size_t keylen = ndigits * sizeof(u64);
> - ssize_t diff = vlen - keylen;
> + size_t bufsize = ndigits * sizeof(u64);
> + ssize_t diff = vlen - bufsize;
> const char *d = value;
> u8 rs[ECC_MAX_BYTES];
>
> @@ -58,7 +58,7 @@ static int ecdsa_get_signature_rs(u64 *dest, size_t hdrlen, unsigned char tag,
> if (diff)
> return -EINVAL;
> }
> - if (-diff >= keylen)
> + if (-diff >= bufsize)
> return -EINVAL;
>
> if (diff) {
> @@ -138,7 +138,7 @@ static int ecdsa_verify(struct akcipher_request *req)
> {
> struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
> struct ecc_ctx *ctx = akcipher_tfm_ctx(tfm);
> - size_t keylen = ctx->curve->g.ndigits * sizeof(u64);
> + size_t bufsize = ctx->curve->g.ndigits * sizeof(u64);
> struct ecdsa_signature_ctx sig_ctx = {
> .curve = ctx->curve,
> };
> @@ -165,14 +165,14 @@ static int ecdsa_verify(struct akcipher_request *req)
> goto error;
>
> /* if the hash is shorter then we will add leading zeros to fit to ndigits */
> - diff = keylen - req->dst_len;
> + diff = bufsize - req->dst_len;
> if (diff >= 0) {
> if (diff)
> memset(rawhash, 0, diff);
> memcpy(&rawhash[diff], buffer + req->src_len, req->dst_len);
> } else if (diff < 0) {
> /* given hash is longer, we take the left-most bytes */
> - memcpy(&rawhash, buffer + req->src_len, keylen);
> + memcpy(&rawhash, buffer + req->src_len, bufsize);
> }
>
> ecc_swap_digits((u64 *)rawhash, hash, ctx->curve->g.ndigits);
Reviewed-by: Jarkko Sakkinen <[email protected]>
BR, Jarkko
On Wed Mar 20, 2024 at 1:47 PM EET, Stefan Berger wrote:
> Adjust the calculation of the maximum signature size for support of
> NIST P521. While existing curves may prepend a 0 byte to their coordinates
> (to make the number positive), NIST P521 will not do this since only the
> first bit in the most significant byte is used.
>
> If the encoding of the x & y coordinates requires at least 128 bytes then
> an additional byte is needed for the encoding of the length. Take this into
> account when calculating the maximum signature size.
>
> Signed-off-by: Stefan Berger <[email protected]>
> Reviewed-by: Lukas Wunner <[email protected]>
> Tested-by: Lukas Wunner <[email protected]>
> ---
> crypto/asymmetric_keys/public_key.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
> index e5f22691febd..16cc0be28929 100644
> --- a/crypto/asymmetric_keys/public_key.c
> +++ b/crypto/asymmetric_keys/public_key.c
> @@ -233,6 +233,7 @@ static int software_key_query(const struct kernel_pkey_params *params,
> info->key_size = len * 8;
>
> if (strncmp(pkey->pkey_algo, "ecdsa", 5) == 0) {
> + int slen = len;
> /*
> * ECDSA key sizes are much smaller than RSA, and thus could
> * operate on (hashed) inputs that are larger than key size.
> @@ -246,8 +247,19 @@ static int software_key_query(const struct kernel_pkey_params *params,
> * Verify takes ECDSA-Sig (described in RFC 5480) as input,
> * which is actually 2 'key_size'-bit integers encoded in
> * ASN.1. Account for the ASN.1 encoding overhead here.
> + *
> + * NIST P192/256/384 may prepend a '0' to a coordinate to
> + * indicate a positive integer. NIST P521 never needs it.
> */
> - info->max_sig_size = 2 * (len + 3) + 2;
> + if (strcmp(pkey->pkey_algo, "ecdsa-nist-p521") != 0)
> + slen += 1;
> + /* Length of encoding the x & y coordinates */
> + slen = 2 * (slen + 2);
> + /*
> + * If coordinate encoding takes at least 128 bytes then an
> + * additional byte for length encoding is needed.
> + */
> + info->max_sig_size = 1 + (slen >= 128) + 1 + slen;
> } else {
> info->max_data_size = len;
> info->max_sig_size = len;
Reviewed-by: Jarkko Sakkinen <[email protected]>
BR, Jarkko
On Thu Mar 21, 2024 at 7:42 PM EET, Stefan Berger wrote:
>
>
> On 3/21/24 13:17, Jarkko Sakkinen wrote:
> > On Wed Mar 20, 2024 at 1:47 PM EET, Stefan Berger wrote:
> >> Add the number of bits a curve has to the ecc_curve definition to be able
> >> to derive the number of bytes a curve requires for its coordinates from it.
> >> It also allows one to identify a curve by its particular size. Set the
> >> number of bits on all curve definitions.
> >>
> >> Signed-off-by: Stefan Berger <[email protected]>
> >> Tested-by: Lukas Wunner <[email protected]>
> >> ---
>
> >> .y = tc512b_g_y,
> >> diff --git a/include/crypto/ecc_curve.h b/include/crypto/ecc_curve.h
> >> index 70964781eb68..63d5754e7614 100644
> >> --- a/include/crypto/ecc_curve.h
> >> +++ b/include/crypto/ecc_curve.h
> >> @@ -23,6 +23,7 @@ struct ecc_point {
> >> * struct ecc_curve - definition of elliptic curve
> >> *
> >> * @name: Short name of the curve.
> >> + * @nbits: The number of bits of a curve.
> >> * @g: Generator point of the curve.
> >> * @p: Prime number, if Barrett's reduction is used for this curve
> >> * pre-calculated value 'mu' is appended to the @p after ndigits.
> >> @@ -34,6 +35,7 @@ struct ecc_point {
> >> */
> >> struct ecc_curve {
> >> char *name;
> >> + unsigned int nbits;
> >
> > Nit:
> >
> > Hmm not strongly opionated here but wouldn't it be more consistent to
> > use u32 here as the types below are also exact bitsize types?
>
> I will change this for v8. I will probably delay v8 until this patch
> here has been queued for upstreaming because 11/13 will need a similar
> module alias.
>
> https://lore.kernel.org/linux-crypto/[email protected]/T/#u
Right for this:
Reviewed-by: Jarkko Sakkinen <[email protected]>
... given that I don't have strong opinion on the choice :-)
BR, Jarkko
On Wed, Mar 20, 2024 at 08:44:52AM -0400, Stefan Berger wrote:
> On 3/20/24 07:47, Stefan Berger wrote:
> > This series adds support for the NIST P521 curve to the ecdsa module
> > to enable signature verification with it.
> >
> > An issue with the current code in ecdsa is that it assumes that input
> > arrays providing key coordinates for example, are arrays of digits
> > (a 'digit' is a 'u64'). This works well for all currently supported
> > curves, such as NIST P192/256/384, but does not work for NIST P521 where
> > coordinates are 8 digits + 2 bytes long. So some of the changes deal with
> > converting byte arrays to digits and adjusting tests on input byte
> > array lengths to tolerate arrays not providing multiples of 8 bytes.
I've tested the whole series successfully on v6.9-rc1 by authenticating
a PCI device with a NIST P521 certificate using my PCI/CMA development
branch: https://github.com/l1k/linux/commits/doe
Tested-by: Lukas Wunner <[email protected]>