Index: mozilla/security/nss/lib/freebl/ec.c |
=================================================================== |
--- mozilla/security/nss/lib/freebl/ec.c (revision 191424) |
+++ mozilla/security/nss/lib/freebl/ec.c (working copy) |
@@ -1,1080 +0,0 @@ |
-/* This Source Code Form is subject to the terms of the Mozilla Public |
- * License, v. 2.0. If a copy of the MPL was not distributed with this |
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
- |
-#ifdef FREEBL_NO_DEPEND |
-#include "stubs.h" |
-#endif |
- |
- |
-#include "blapi.h" |
-#include "prerr.h" |
-#include "secerr.h" |
-#include "secmpi.h" |
-#include "secitem.h" |
-#include "mplogic.h" |
-#include "ec.h" |
-#include "ecl.h" |
- |
-#ifdef NSS_ENABLE_ECC |
- |
-/* |
- * Returns true if pointP is the point at infinity, false otherwise |
- */ |
-PRBool |
-ec_point_at_infinity(SECItem *pointP) |
-{ |
- unsigned int i; |
- |
- for (i = 1; i < pointP->len; i++) { |
- if (pointP->data[i] != 0x00) return PR_FALSE; |
- } |
- |
- return PR_TRUE; |
-} |
- |
-/* |
- * Computes scalar point multiplication pointQ = k1 * G + k2 * pointP for |
- * the curve whose parameters are encoded in params with base point G. |
- */ |
-SECStatus |
-ec_points_mul(const ECParams *params, const mp_int *k1, const mp_int *k2, |
- const SECItem *pointP, SECItem *pointQ) |
-{ |
- mp_int Px, Py, Qx, Qy; |
- mp_int Gx, Gy, order, irreducible, a, b; |
-#if 0 /* currently don't support non-named curves */ |
- unsigned int irr_arr[5]; |
-#endif |
- ECGroup *group = NULL; |
- SECStatus rv = SECFailure; |
- mp_err err = MP_OKAY; |
- int len; |
- |
-#if EC_DEBUG |
- int i; |
- char mpstr[256]; |
- |
- printf("ec_points_mul: params [len=%d]:", params->DEREncoding.len); |
- for (i = 0; i < params->DEREncoding.len; i++) |
- printf("%02x:", params->DEREncoding.data[i]); |
- printf("\n"); |
- |
- if (k1 != NULL) { |
- mp_tohex(k1, mpstr); |
- printf("ec_points_mul: scalar k1: %s\n", mpstr); |
- mp_todecimal(k1, mpstr); |
- printf("ec_points_mul: scalar k1: %s (dec)\n", mpstr); |
- } |
- |
- if (k2 != NULL) { |
- mp_tohex(k2, mpstr); |
- printf("ec_points_mul: scalar k2: %s\n", mpstr); |
- mp_todecimal(k2, mpstr); |
- printf("ec_points_mul: scalar k2: %s (dec)\n", mpstr); |
- } |
- |
- if (pointP != NULL) { |
- printf("ec_points_mul: pointP [len=%d]:", pointP->len); |
- for (i = 0; i < pointP->len; i++) |
- printf("%02x:", pointP->data[i]); |
- printf("\n"); |
- } |
-#endif |
- |
- /* NOTE: We only support uncompressed points for now */ |
- len = (params->fieldID.size + 7) >> 3; |
- if (pointP != NULL) { |
- if ((pointP->data[0] != EC_POINT_FORM_UNCOMPRESSED) || |
- (pointP->len != (2 * len + 1))) { |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_EC_POINT_FORM); |
- return SECFailure; |
- }; |
- } |
- |
- MP_DIGITS(&Px) = 0; |
- MP_DIGITS(&Py) = 0; |
- MP_DIGITS(&Qx) = 0; |
- MP_DIGITS(&Qy) = 0; |
- MP_DIGITS(&Gx) = 0; |
- MP_DIGITS(&Gy) = 0; |
- MP_DIGITS(&order) = 0; |
- MP_DIGITS(&irreducible) = 0; |
- MP_DIGITS(&a) = 0; |
- MP_DIGITS(&b) = 0; |
- CHECK_MPI_OK( mp_init(&Px) ); |
- CHECK_MPI_OK( mp_init(&Py) ); |
- CHECK_MPI_OK( mp_init(&Qx) ); |
- CHECK_MPI_OK( mp_init(&Qy) ); |
- CHECK_MPI_OK( mp_init(&Gx) ); |
- CHECK_MPI_OK( mp_init(&Gy) ); |
- CHECK_MPI_OK( mp_init(&order) ); |
- CHECK_MPI_OK( mp_init(&irreducible) ); |
- CHECK_MPI_OK( mp_init(&a) ); |
- CHECK_MPI_OK( mp_init(&b) ); |
- |
- if ((k2 != NULL) && (pointP != NULL)) { |
- /* Initialize Px and Py */ |
- CHECK_MPI_OK( mp_read_unsigned_octets(&Px, pointP->data + 1, (mp_size) len) ); |
- CHECK_MPI_OK( mp_read_unsigned_octets(&Py, pointP->data + 1 + len, (mp_size) len) ); |
- } |
- |
- /* construct from named params, if possible */ |
- if (params->name != ECCurve_noName) { |
- group = ECGroup_fromName(params->name); |
- } |
- |
-#if 0 /* currently don't support non-named curves */ |
- if (group == NULL) { |
- /* Set up mp_ints containing the curve coefficients */ |
- CHECK_MPI_OK( mp_read_unsigned_octets(&Gx, params->base.data + 1, |
- (mp_size) len) ); |
- CHECK_MPI_OK( mp_read_unsigned_octets(&Gy, params->base.data + 1 + len, |
- (mp_size) len) ); |
- SECITEM_TO_MPINT( params->order, &order ); |
- SECITEM_TO_MPINT( params->curve.a, &a ); |
- SECITEM_TO_MPINT( params->curve.b, &b ); |
- if (params->fieldID.type == ec_field_GFp) { |
- SECITEM_TO_MPINT( params->fieldID.u.prime, &irreducible ); |
- group = ECGroup_consGFp(&irreducible, &a, &b, &Gx, &Gy, &order, params->cofactor); |
- } else { |
- SECITEM_TO_MPINT( params->fieldID.u.poly, &irreducible ); |
- irr_arr[0] = params->fieldID.size; |
- irr_arr[1] = params->fieldID.k1; |
- irr_arr[2] = params->fieldID.k2; |
- irr_arr[3] = params->fieldID.k3; |
- irr_arr[4] = 0; |
- group = ECGroup_consGF2m(&irreducible, irr_arr, &a, &b, &Gx, &Gy, &order, params->cofactor); |
- } |
- } |
-#endif |
- if (group == NULL) |
- goto cleanup; |
- |
- if ((k2 != NULL) && (pointP != NULL)) { |
- CHECK_MPI_OK( ECPoints_mul(group, k1, k2, &Px, &Py, &Qx, &Qy) ); |
- } else { |
- CHECK_MPI_OK( ECPoints_mul(group, k1, NULL, NULL, NULL, &Qx, &Qy) ); |
- } |
- |
- /* Construct the SECItem representation of point Q */ |
- pointQ->data[0] = EC_POINT_FORM_UNCOMPRESSED; |
- CHECK_MPI_OK( mp_to_fixlen_octets(&Qx, pointQ->data + 1, |
- (mp_size) len) ); |
- CHECK_MPI_OK( mp_to_fixlen_octets(&Qy, pointQ->data + 1 + len, |
- (mp_size) len) ); |
- |
- rv = SECSuccess; |
- |
-#if EC_DEBUG |
- printf("ec_points_mul: pointQ [len=%d]:", pointQ->len); |
- for (i = 0; i < pointQ->len; i++) |
- printf("%02x:", pointQ->data[i]); |
- printf("\n"); |
-#endif |
- |
-cleanup: |
- ECGroup_free(group); |
- mp_clear(&Px); |
- mp_clear(&Py); |
- mp_clear(&Qx); |
- mp_clear(&Qy); |
- mp_clear(&Gx); |
- mp_clear(&Gy); |
- mp_clear(&order); |
- mp_clear(&irreducible); |
- mp_clear(&a); |
- mp_clear(&b); |
- if (err) { |
- MP_TO_SEC_ERROR(err); |
- rv = SECFailure; |
- } |
- |
- return rv; |
-} |
-#endif /* NSS_ENABLE_ECC */ |
- |
-/* Generates a new EC key pair. The private key is a supplied |
- * value and the public key is the result of performing a scalar |
- * point multiplication of that value with the curve's base point. |
- */ |
-SECStatus |
-ec_NewKey(ECParams *ecParams, ECPrivateKey **privKey, |
- const unsigned char *privKeyBytes, int privKeyLen) |
-{ |
- SECStatus rv = SECFailure; |
-#ifdef NSS_ENABLE_ECC |
- PRArenaPool *arena; |
- ECPrivateKey *key; |
- mp_int k; |
- mp_err err = MP_OKAY; |
- int len; |
- |
-#if EC_DEBUG |
- printf("ec_NewKey called\n"); |
-#endif |
- MP_DIGITS(&k) = 0; |
- |
- if (!ecParams || !privKey || !privKeyBytes || (privKeyLen < 0)) { |
- PORT_SetError(SEC_ERROR_INVALID_ARGS); |
- return SECFailure; |
- } |
- |
- /* Initialize an arena for the EC key. */ |
- if (!(arena = PORT_NewArena(NSS_FREEBL_DEFAULT_CHUNKSIZE))) |
- return SECFailure; |
- |
- key = (ECPrivateKey *)PORT_ArenaZAlloc(arena, sizeof(ECPrivateKey)); |
- if (!key) { |
- PORT_FreeArena(arena, PR_TRUE); |
- return SECFailure; |
- } |
- |
- /* Set the version number (SEC 1 section C.4 says it should be 1) */ |
- SECITEM_AllocItem(arena, &key->version, 1); |
- key->version.data[0] = 1; |
- |
- /* Copy all of the fields from the ECParams argument to the |
- * ECParams structure within the private key. |
- */ |
- key->ecParams.arena = arena; |
- key->ecParams.type = ecParams->type; |
- key->ecParams.fieldID.size = ecParams->fieldID.size; |
- key->ecParams.fieldID.type = ecParams->fieldID.type; |
- if (ecParams->fieldID.type == ec_field_GFp) { |
- CHECK_SEC_OK(SECITEM_CopyItem(arena, &key->ecParams.fieldID.u.prime, |
- &ecParams->fieldID.u.prime)); |
- } else { |
- CHECK_SEC_OK(SECITEM_CopyItem(arena, &key->ecParams.fieldID.u.poly, |
- &ecParams->fieldID.u.poly)); |
- } |
- key->ecParams.fieldID.k1 = ecParams->fieldID.k1; |
- key->ecParams.fieldID.k2 = ecParams->fieldID.k2; |
- key->ecParams.fieldID.k3 = ecParams->fieldID.k3; |
- CHECK_SEC_OK(SECITEM_CopyItem(arena, &key->ecParams.curve.a, |
- &ecParams->curve.a)); |
- CHECK_SEC_OK(SECITEM_CopyItem(arena, &key->ecParams.curve.b, |
- &ecParams->curve.b)); |
- CHECK_SEC_OK(SECITEM_CopyItem(arena, &key->ecParams.curve.seed, |
- &ecParams->curve.seed)); |
- CHECK_SEC_OK(SECITEM_CopyItem(arena, &key->ecParams.base, |
- &ecParams->base)); |
- CHECK_SEC_OK(SECITEM_CopyItem(arena, &key->ecParams.order, |
- &ecParams->order)); |
- key->ecParams.cofactor = ecParams->cofactor; |
- CHECK_SEC_OK(SECITEM_CopyItem(arena, &key->ecParams.DEREncoding, |
- &ecParams->DEREncoding)); |
- key->ecParams.name = ecParams->name; |
- CHECK_SEC_OK(SECITEM_CopyItem(arena, &key->ecParams.curveOID, |
- &ecParams->curveOID)); |
- |
- len = (ecParams->fieldID.size + 7) >> 3; |
- SECITEM_AllocItem(arena, &key->publicValue, 2*len + 1); |
- len = ecParams->order.len; |
- SECITEM_AllocItem(arena, &key->privateValue, len); |
- |
- /* Copy private key */ |
- if (privKeyLen >= len) { |
- memcpy(key->privateValue.data, privKeyBytes, len); |
- } else { |
- memset(key->privateValue.data, 0, (len - privKeyLen)); |
- memcpy(key->privateValue.data + (len - privKeyLen), privKeyBytes, privKeyLen); |
- } |
- |
- /* Compute corresponding public key */ |
- CHECK_MPI_OK( mp_init(&k) ); |
- CHECK_MPI_OK( mp_read_unsigned_octets(&k, key->privateValue.data, |
- (mp_size) len) ); |
- |
- rv = ec_points_mul(ecParams, &k, NULL, NULL, &(key->publicValue)); |
- if (rv != SECSuccess) goto cleanup; |
- *privKey = key; |
- |
-cleanup: |
- mp_clear(&k); |
- if (rv) |
- PORT_FreeArena(arena, PR_TRUE); |
- |
-#if EC_DEBUG |
- printf("ec_NewKey returning %s\n", |
- (rv == SECSuccess) ? "success" : "failure"); |
-#endif |
-#else |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_KEYALG); |
-#endif /* NSS_ENABLE_ECC */ |
- |
- return rv; |
- |
-} |
- |
-/* Generates a new EC key pair. The private key is a supplied |
- * random value (in seed) and the public key is the result of |
- * performing a scalar point multiplication of that value with |
- * the curve's base point. |
- */ |
-SECStatus |
-EC_NewKeyFromSeed(ECParams *ecParams, ECPrivateKey **privKey, |
- const unsigned char *seed, int seedlen) |
-{ |
- SECStatus rv = SECFailure; |
-#ifdef NSS_ENABLE_ECC |
- rv = ec_NewKey(ecParams, privKey, seed, seedlen); |
-#else |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_KEYALG); |
-#endif /* NSS_ENABLE_ECC */ |
- return rv; |
-} |
- |
-#ifdef NSS_ENABLE_ECC |
-/* Generate a random private key using the algorithm A.4.1 of ANSI X9.62, |
- * modified a la FIPS 186-2 Change Notice 1 to eliminate the bias in the |
- * random number generator. |
- * |
- * Parameters |
- * - order: a buffer that holds the curve's group order |
- * - len: the length in octets of the order buffer |
- * |
- * Return Value |
- * Returns a buffer of len octets that holds the private key. The caller |
- * is responsible for freeing the buffer with PORT_ZFree. |
- */ |
-static unsigned char * |
-ec_GenerateRandomPrivateKey(const unsigned char *order, int len) |
-{ |
- SECStatus rv = SECSuccess; |
- mp_err err; |
- unsigned char *privKeyBytes = NULL; |
- mp_int privKeyVal, order_1, one; |
- |
- MP_DIGITS(&privKeyVal) = 0; |
- MP_DIGITS(&order_1) = 0; |
- MP_DIGITS(&one) = 0; |
- CHECK_MPI_OK( mp_init(&privKeyVal) ); |
- CHECK_MPI_OK( mp_init(&order_1) ); |
- CHECK_MPI_OK( mp_init(&one) ); |
- |
- /* Generates 2*len random bytes using the global random bit generator |
- * (which implements Algorithm 1 of FIPS 186-2 Change Notice 1) then |
- * reduces modulo the group order. |
- */ |
- if ((privKeyBytes = PORT_Alloc(2*len)) == NULL) goto cleanup; |
- CHECK_SEC_OK( RNG_GenerateGlobalRandomBytes(privKeyBytes, 2*len) ); |
- CHECK_MPI_OK( mp_read_unsigned_octets(&privKeyVal, privKeyBytes, 2*len) ); |
- CHECK_MPI_OK( mp_read_unsigned_octets(&order_1, order, len) ); |
- CHECK_MPI_OK( mp_set_int(&one, 1) ); |
- CHECK_MPI_OK( mp_sub(&order_1, &one, &order_1) ); |
- CHECK_MPI_OK( mp_mod(&privKeyVal, &order_1, &privKeyVal) ); |
- CHECK_MPI_OK( mp_add(&privKeyVal, &one, &privKeyVal) ); |
- CHECK_MPI_OK( mp_to_fixlen_octets(&privKeyVal, privKeyBytes, len) ); |
- memset(privKeyBytes+len, 0, len); |
-cleanup: |
- mp_clear(&privKeyVal); |
- mp_clear(&order_1); |
- mp_clear(&one); |
- if (err < MP_OKAY) { |
- MP_TO_SEC_ERROR(err); |
- rv = SECFailure; |
- } |
- if (rv != SECSuccess && privKeyBytes) { |
- PORT_Free(privKeyBytes); |
- privKeyBytes = NULL; |
- } |
- return privKeyBytes; |
-} |
-#endif /* NSS_ENABLE_ECC */ |
- |
-/* Generates a new EC key pair. The private key is a random value and |
- * the public key is the result of performing a scalar point multiplication |
- * of that value with the curve's base point. |
- */ |
-SECStatus |
-EC_NewKey(ECParams *ecParams, ECPrivateKey **privKey) |
-{ |
- SECStatus rv = SECFailure; |
-#ifdef NSS_ENABLE_ECC |
- int len; |
- unsigned char *privKeyBytes = NULL; |
- |
- if (!ecParams) { |
- PORT_SetError(SEC_ERROR_INVALID_ARGS); |
- return SECFailure; |
- } |
- |
- len = ecParams->order.len; |
- privKeyBytes = ec_GenerateRandomPrivateKey(ecParams->order.data, len); |
- if (privKeyBytes == NULL) goto cleanup; |
- /* generate public key */ |
- CHECK_SEC_OK( ec_NewKey(ecParams, privKey, privKeyBytes, len) ); |
- |
-cleanup: |
- if (privKeyBytes) { |
- PORT_ZFree(privKeyBytes, len); |
- } |
-#if EC_DEBUG |
- printf("EC_NewKey returning %s\n", |
- (rv == SECSuccess) ? "success" : "failure"); |
-#endif |
-#else |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_KEYALG); |
-#endif /* NSS_ENABLE_ECC */ |
- |
- return rv; |
-} |
- |
-/* Validates an EC public key as described in Section 5.2.2 of |
- * X9.62. The ECDH primitive when used without the cofactor does |
- * not address small subgroup attacks, which may occur when the |
- * public key is not valid. These attacks can be prevented by |
- * validating the public key before using ECDH. |
- */ |
-SECStatus |
-EC_ValidatePublicKey(ECParams *ecParams, SECItem *publicValue) |
-{ |
-#ifdef NSS_ENABLE_ECC |
- mp_int Px, Py; |
- ECGroup *group = NULL; |
- SECStatus rv = SECFailure; |
- mp_err err = MP_OKAY; |
- int len; |
- |
- if (!ecParams || !publicValue) { |
- PORT_SetError(SEC_ERROR_INVALID_ARGS); |
- return SECFailure; |
- } |
- |
- /* NOTE: We only support uncompressed points for now */ |
- len = (ecParams->fieldID.size + 7) >> 3; |
- if (publicValue->data[0] != EC_POINT_FORM_UNCOMPRESSED) { |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_EC_POINT_FORM); |
- return SECFailure; |
- } else if (publicValue->len != (2 * len + 1)) { |
- PORT_SetError(SEC_ERROR_BAD_KEY); |
- return SECFailure; |
- } |
- |
- MP_DIGITS(&Px) = 0; |
- MP_DIGITS(&Py) = 0; |
- CHECK_MPI_OK( mp_init(&Px) ); |
- CHECK_MPI_OK( mp_init(&Py) ); |
- |
- /* Initialize Px and Py */ |
- CHECK_MPI_OK( mp_read_unsigned_octets(&Px, publicValue->data + 1, (mp_size) len) ); |
- CHECK_MPI_OK( mp_read_unsigned_octets(&Py, publicValue->data + 1 + len, (mp_size) len) ); |
- |
- /* construct from named params */ |
- group = ECGroup_fromName(ecParams->name); |
- if (group == NULL) { |
- /* |
- * ECGroup_fromName fails if ecParams->name is not a valid |
- * ECCurveName value, or if we run out of memory, or perhaps |
- * for other reasons. Unfortunately if ecParams->name is a |
- * valid ECCurveName value, we don't know what the right error |
- * code should be because ECGroup_fromName doesn't return an |
- * error code to the caller. Set err to MP_UNDEF because |
- * that's what ECGroup_fromName uses internally. |
- */ |
- if ((ecParams->name <= ECCurve_noName) || |
- (ecParams->name >= ECCurve_pastLastCurve)) { |
- err = MP_BADARG; |
- } else { |
- err = MP_UNDEF; |
- } |
- goto cleanup; |
- } |
- |
- /* validate public point */ |
- if ((err = ECPoint_validate(group, &Px, &Py)) < MP_YES) { |
- if (err == MP_NO) { |
- PORT_SetError(SEC_ERROR_BAD_KEY); |
- rv = SECFailure; |
- err = MP_OKAY; /* don't change the error code */ |
- } |
- goto cleanup; |
- } |
- |
- rv = SECSuccess; |
- |
-cleanup: |
- ECGroup_free(group); |
- mp_clear(&Px); |
- mp_clear(&Py); |
- if (err) { |
- MP_TO_SEC_ERROR(err); |
- rv = SECFailure; |
- } |
- return rv; |
-#else |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_KEYALG); |
- return SECFailure; |
-#endif /* NSS_ENABLE_ECC */ |
-} |
- |
-/* |
-** Performs an ECDH key derivation by computing the scalar point |
-** multiplication of privateValue and publicValue (with or without the |
-** cofactor) and returns the x-coordinate of the resulting elliptic |
-** curve point in derived secret. If successful, derivedSecret->data |
-** is set to the address of the newly allocated buffer containing the |
-** derived secret, and derivedSecret->len is the size of the secret |
-** produced. It is the caller's responsibility to free the allocated |
-** buffer containing the derived secret. |
-*/ |
-SECStatus |
-ECDH_Derive(SECItem *publicValue, |
- ECParams *ecParams, |
- SECItem *privateValue, |
- PRBool withCofactor, |
- SECItem *derivedSecret) |
-{ |
- SECStatus rv = SECFailure; |
-#ifdef NSS_ENABLE_ECC |
- unsigned int len = 0; |
- SECItem pointQ = {siBuffer, NULL, 0}; |
- mp_int k; /* to hold the private value */ |
- mp_int cofactor; |
- mp_err err = MP_OKAY; |
-#if EC_DEBUG |
- int i; |
-#endif |
- |
- if (!publicValue || !ecParams || !privateValue || |
- !derivedSecret) { |
- PORT_SetError(SEC_ERROR_INVALID_ARGS); |
- return SECFailure; |
- } |
- |
- MP_DIGITS(&k) = 0; |
- memset(derivedSecret, 0, sizeof *derivedSecret); |
- len = (ecParams->fieldID.size + 7) >> 3; |
- pointQ.len = 2*len + 1; |
- if ((pointQ.data = PORT_Alloc(2*len + 1)) == NULL) goto cleanup; |
- |
- CHECK_MPI_OK( mp_init(&k) ); |
- CHECK_MPI_OK( mp_read_unsigned_octets(&k, privateValue->data, |
- (mp_size) privateValue->len) ); |
- |
- if (withCofactor && (ecParams->cofactor != 1)) { |
- /* multiply k with the cofactor */ |
- MP_DIGITS(&cofactor) = 0; |
- CHECK_MPI_OK( mp_init(&cofactor) ); |
- mp_set(&cofactor, ecParams->cofactor); |
- CHECK_MPI_OK( mp_mul(&k, &cofactor, &k) ); |
- } |
- |
- /* Multiply our private key and peer's public point */ |
- if (ec_points_mul(ecParams, NULL, &k, publicValue, &pointQ) != SECSuccess) |
- goto cleanup; |
- if (ec_point_at_infinity(&pointQ)) { |
- PORT_SetError(SEC_ERROR_BAD_KEY); /* XXX better error code? */ |
- goto cleanup; |
- } |
- |
- /* Allocate memory for the derived secret and copy |
- * the x co-ordinate of pointQ into it. |
- */ |
- SECITEM_AllocItem(NULL, derivedSecret, len); |
- memcpy(derivedSecret->data, pointQ.data + 1, len); |
- |
- rv = SECSuccess; |
- |
-#if EC_DEBUG |
- printf("derived_secret:\n"); |
- for (i = 0; i < derivedSecret->len; i++) |
- printf("%02x:", derivedSecret->data[i]); |
- printf("\n"); |
-#endif |
- |
-cleanup: |
- mp_clear(&k); |
- |
- if (err) { |
- MP_TO_SEC_ERROR(err); |
- } |
- |
- if (pointQ.data) { |
- PORT_ZFree(pointQ.data, 2*len + 1); |
- } |
-#else |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_KEYALG); |
-#endif /* NSS_ENABLE_ECC */ |
- |
- return rv; |
-} |
- |
-/* Computes the ECDSA signature (a concatenation of two values r and s) |
- * on the digest using the given key and the random value kb (used in |
- * computing s). |
- */ |
-SECStatus |
-ECDSA_SignDigestWithSeed(ECPrivateKey *key, SECItem *signature, |
- const SECItem *digest, const unsigned char *kb, const int kblen) |
-{ |
- SECStatus rv = SECFailure; |
-#ifdef NSS_ENABLE_ECC |
- mp_int x1; |
- mp_int d, k; /* private key, random integer */ |
- mp_int r, s; /* tuple (r, s) is the signature */ |
- mp_int n; |
- mp_err err = MP_OKAY; |
- ECParams *ecParams = NULL; |
- SECItem kGpoint = { siBuffer, NULL, 0}; |
- int flen = 0; /* length in bytes of the field size */ |
- unsigned olen; /* length in bytes of the base point order */ |
- unsigned obits; /* length in bits of the base point order */ |
- |
-#if EC_DEBUG |
- char mpstr[256]; |
-#endif |
- |
- /* Initialize MPI integers. */ |
- /* must happen before the first potential call to cleanup */ |
- MP_DIGITS(&x1) = 0; |
- MP_DIGITS(&d) = 0; |
- MP_DIGITS(&k) = 0; |
- MP_DIGITS(&r) = 0; |
- MP_DIGITS(&s) = 0; |
- MP_DIGITS(&n) = 0; |
- |
- /* Check args */ |
- if (!key || !signature || !digest || !kb || (kblen < 0)) { |
- PORT_SetError(SEC_ERROR_INVALID_ARGS); |
- goto cleanup; |
- } |
- |
- ecParams = &(key->ecParams); |
- flen = (ecParams->fieldID.size + 7) >> 3; |
- olen = ecParams->order.len; |
- if (signature->data == NULL) { |
- /* a call to get the signature length only */ |
- goto finish; |
- } |
- if (signature->len < 2*olen) { |
- PORT_SetError(SEC_ERROR_OUTPUT_LEN); |
- goto cleanup; |
- } |
- |
- |
- CHECK_MPI_OK( mp_init(&x1) ); |
- CHECK_MPI_OK( mp_init(&d) ); |
- CHECK_MPI_OK( mp_init(&k) ); |
- CHECK_MPI_OK( mp_init(&r) ); |
- CHECK_MPI_OK( mp_init(&s) ); |
- CHECK_MPI_OK( mp_init(&n) ); |
- |
- SECITEM_TO_MPINT( ecParams->order, &n ); |
- SECITEM_TO_MPINT( key->privateValue, &d ); |
- |
- CHECK_MPI_OK( mp_read_unsigned_octets(&k, kb, kblen) ); |
- /* Make sure k is in the interval [1, n-1] */ |
- if ((mp_cmp_z(&k) <= 0) || (mp_cmp(&k, &n) >= 0)) { |
-#if EC_DEBUG |
- printf("k is outside [1, n-1]\n"); |
- mp_tohex(&k, mpstr); |
- printf("k : %s \n", mpstr); |
- mp_tohex(&n, mpstr); |
- printf("n : %s \n", mpstr); |
-#endif |
- PORT_SetError(SEC_ERROR_NEED_RANDOM); |
- goto cleanup; |
- } |
- |
- /* |
- ** We do not want timing information to leak the length of k, |
- ** so we compute k*G using an equivalent scalar of fixed |
- ** bit-length. |
- ** Fix based on patch for ECDSA timing attack in the paper |
- ** by Billy Bob Brumley and Nicola Tuveri at |
- ** http://eprint.iacr.org/2011/232 |
- ** |
- ** How do we convert k to a value of a fixed bit-length? |
- ** k starts off as an integer satisfying 0 <= k < n. Hence, |
- ** n <= k+n < 2n, which means k+n has either the same number |
- ** of bits as n or one more bit than n. If k+n has the same |
- ** number of bits as n, the second addition ensures that the |
- ** final value has exactly one more bit than n. Thus, we |
- ** always end up with a value that exactly one more bit than n. |
- */ |
- CHECK_MPI_OK( mp_add(&k, &n, &k) ); |
- if (mpl_significant_bits(&k) <= mpl_significant_bits(&n)) { |
- CHECK_MPI_OK( mp_add(&k, &n, &k) ); |
- } |
- |
- /* |
- ** ANSI X9.62, Section 5.3.2, Step 2 |
- ** |
- ** Compute kG |
- */ |
- kGpoint.len = 2*flen + 1; |
- kGpoint.data = PORT_Alloc(2*flen + 1); |
- if ((kGpoint.data == NULL) || |
- (ec_points_mul(ecParams, &k, NULL, NULL, &kGpoint) |
- != SECSuccess)) |
- goto cleanup; |
- |
- /* |
- ** ANSI X9.62, Section 5.3.3, Step 1 |
- ** |
- ** Extract the x co-ordinate of kG into x1 |
- */ |
- CHECK_MPI_OK( mp_read_unsigned_octets(&x1, kGpoint.data + 1, |
- (mp_size) flen) ); |
- |
- /* |
- ** ANSI X9.62, Section 5.3.3, Step 2 |
- ** |
- ** r = x1 mod n NOTE: n is the order of the curve |
- */ |
- CHECK_MPI_OK( mp_mod(&x1, &n, &r) ); |
- |
- /* |
- ** ANSI X9.62, Section 5.3.3, Step 3 |
- ** |
- ** verify r != 0 |
- */ |
- if (mp_cmp_z(&r) == 0) { |
- PORT_SetError(SEC_ERROR_NEED_RANDOM); |
- goto cleanup; |
- } |
- |
- /* |
- ** ANSI X9.62, Section 5.3.3, Step 4 |
- ** |
- ** s = (k**-1 * (HASH(M) + d*r)) mod n |
- */ |
- SECITEM_TO_MPINT(*digest, &s); /* s = HASH(M) */ |
- |
- /* In the definition of EC signing, digests are truncated |
- * to the length of n in bits. |
- * (see SEC 1 "Elliptic Curve Digit Signature Algorithm" section 4.1.*/ |
- CHECK_MPI_OK( (obits = mpl_significant_bits(&n)) ); |
- if (digest->len*8 > obits) { |
- mpl_rsh(&s,&s,digest->len*8 - obits); |
- } |
- |
-#if EC_DEBUG |
- mp_todecimal(&n, mpstr); |
- printf("n : %s (dec)\n", mpstr); |
- mp_todecimal(&d, mpstr); |
- printf("d : %s (dec)\n", mpstr); |
- mp_tohex(&x1, mpstr); |
- printf("x1: %s\n", mpstr); |
- mp_todecimal(&s, mpstr); |
- printf("digest: %s (decimal)\n", mpstr); |
- mp_todecimal(&r, mpstr); |
- printf("r : %s (dec)\n", mpstr); |
- mp_tohex(&r, mpstr); |
- printf("r : %s\n", mpstr); |
-#endif |
- |
- CHECK_MPI_OK( mp_invmod(&k, &n, &k) ); /* k = k**-1 mod n */ |
- CHECK_MPI_OK( mp_mulmod(&d, &r, &n, &d) ); /* d = d * r mod n */ |
- CHECK_MPI_OK( mp_addmod(&s, &d, &n, &s) ); /* s = s + d mod n */ |
- CHECK_MPI_OK( mp_mulmod(&s, &k, &n, &s) ); /* s = s * k mod n */ |
- |
-#if EC_DEBUG |
- mp_todecimal(&s, mpstr); |
- printf("s : %s (dec)\n", mpstr); |
- mp_tohex(&s, mpstr); |
- printf("s : %s\n", mpstr); |
-#endif |
- |
- /* |
- ** ANSI X9.62, Section 5.3.3, Step 5 |
- ** |
- ** verify s != 0 |
- */ |
- if (mp_cmp_z(&s) == 0) { |
- PORT_SetError(SEC_ERROR_NEED_RANDOM); |
- goto cleanup; |
- } |
- |
- /* |
- ** |
- ** Signature is tuple (r, s) |
- */ |
- CHECK_MPI_OK( mp_to_fixlen_octets(&r, signature->data, olen) ); |
- CHECK_MPI_OK( mp_to_fixlen_octets(&s, signature->data + olen, olen) ); |
-finish: |
- signature->len = 2*olen; |
- |
- rv = SECSuccess; |
- err = MP_OKAY; |
-cleanup: |
- mp_clear(&x1); |
- mp_clear(&d); |
- mp_clear(&k); |
- mp_clear(&r); |
- mp_clear(&s); |
- mp_clear(&n); |
- |
- if (kGpoint.data) { |
- PORT_ZFree(kGpoint.data, 2*flen + 1); |
- } |
- |
- if (err) { |
- MP_TO_SEC_ERROR(err); |
- rv = SECFailure; |
- } |
- |
-#if EC_DEBUG |
- printf("ECDSA signing with seed %s\n", |
- (rv == SECSuccess) ? "succeeded" : "failed"); |
-#endif |
-#else |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_KEYALG); |
-#endif /* NSS_ENABLE_ECC */ |
- |
- return rv; |
-} |
- |
-/* |
-** Computes the ECDSA signature on the digest using the given key |
-** and a random seed. |
-*/ |
-SECStatus |
-ECDSA_SignDigest(ECPrivateKey *key, SECItem *signature, const SECItem *digest) |
-{ |
- SECStatus rv = SECFailure; |
-#ifdef NSS_ENABLE_ECC |
- int len; |
- unsigned char *kBytes= NULL; |
- |
- if (!key) { |
- PORT_SetError(SEC_ERROR_INVALID_ARGS); |
- return SECFailure; |
- } |
- |
- /* Generate random value k */ |
- len = key->ecParams.order.len; |
- kBytes = ec_GenerateRandomPrivateKey(key->ecParams.order.data, len); |
- if (kBytes == NULL) goto cleanup; |
- |
- /* Generate ECDSA signature with the specified k value */ |
- rv = ECDSA_SignDigestWithSeed(key, signature, digest, kBytes, len); |
- |
-cleanup: |
- if (kBytes) { |
- PORT_ZFree(kBytes, len); |
- } |
- |
-#if EC_DEBUG |
- printf("ECDSA signing %s\n", |
- (rv == SECSuccess) ? "succeeded" : "failed"); |
-#endif |
-#else |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_KEYALG); |
-#endif /* NSS_ENABLE_ECC */ |
- |
- return rv; |
-} |
- |
-/* |
-** Checks the signature on the given digest using the key provided. |
-*/ |
-SECStatus |
-ECDSA_VerifyDigest(ECPublicKey *key, const SECItem *signature, |
- const SECItem *digest) |
-{ |
- SECStatus rv = SECFailure; |
-#ifdef NSS_ENABLE_ECC |
- mp_int r_, s_; /* tuple (r', s') is received signature) */ |
- mp_int c, u1, u2, v; /* intermediate values used in verification */ |
- mp_int x1; |
- mp_int n; |
- mp_err err = MP_OKAY; |
- ECParams *ecParams = NULL; |
- SECItem pointC = { siBuffer, NULL, 0 }; |
- int slen; /* length in bytes of a half signature (r or s) */ |
- int flen; /* length in bytes of the field size */ |
- unsigned olen; /* length in bytes of the base point order */ |
- unsigned obits; /* length in bits of the base point order */ |
- |
-#if EC_DEBUG |
- char mpstr[256]; |
- printf("ECDSA verification called\n"); |
-#endif |
- |
- /* Initialize MPI integers. */ |
- /* must happen before the first potential call to cleanup */ |
- MP_DIGITS(&r_) = 0; |
- MP_DIGITS(&s_) = 0; |
- MP_DIGITS(&c) = 0; |
- MP_DIGITS(&u1) = 0; |
- MP_DIGITS(&u2) = 0; |
- MP_DIGITS(&x1) = 0; |
- MP_DIGITS(&v) = 0; |
- MP_DIGITS(&n) = 0; |
- |
- /* Check args */ |
- if (!key || !signature || !digest) { |
- PORT_SetError(SEC_ERROR_INVALID_ARGS); |
- goto cleanup; |
- } |
- |
- ecParams = &(key->ecParams); |
- flen = (ecParams->fieldID.size + 7) >> 3; |
- olen = ecParams->order.len; |
- if (signature->len == 0 || signature->len%2 != 0 || |
- signature->len > 2*olen) { |
- PORT_SetError(SEC_ERROR_INPUT_LEN); |
- goto cleanup; |
- } |
- slen = signature->len/2; |
- |
- SECITEM_AllocItem(NULL, &pointC, 2*flen + 1); |
- if (pointC.data == NULL) |
- goto cleanup; |
- |
- CHECK_MPI_OK( mp_init(&r_) ); |
- CHECK_MPI_OK( mp_init(&s_) ); |
- CHECK_MPI_OK( mp_init(&c) ); |
- CHECK_MPI_OK( mp_init(&u1) ); |
- CHECK_MPI_OK( mp_init(&u2) ); |
- CHECK_MPI_OK( mp_init(&x1) ); |
- CHECK_MPI_OK( mp_init(&v) ); |
- CHECK_MPI_OK( mp_init(&n) ); |
- |
- /* |
- ** Convert received signature (r', s') into MPI integers. |
- */ |
- CHECK_MPI_OK( mp_read_unsigned_octets(&r_, signature->data, slen) ); |
- CHECK_MPI_OK( mp_read_unsigned_octets(&s_, signature->data + slen, slen) ); |
- |
- /* |
- ** ANSI X9.62, Section 5.4.2, Steps 1 and 2 |
- ** |
- ** Verify that 0 < r' < n and 0 < s' < n |
- */ |
- SECITEM_TO_MPINT(ecParams->order, &n); |
- if (mp_cmp_z(&r_) <= 0 || mp_cmp_z(&s_) <= 0 || |
- mp_cmp(&r_, &n) >= 0 || mp_cmp(&s_, &n) >= 0) { |
- PORT_SetError(SEC_ERROR_BAD_SIGNATURE); |
- goto cleanup; /* will return rv == SECFailure */ |
- } |
- |
- /* |
- ** ANSI X9.62, Section 5.4.2, Step 3 |
- ** |
- ** c = (s')**-1 mod n |
- */ |
- CHECK_MPI_OK( mp_invmod(&s_, &n, &c) ); /* c = (s')**-1 mod n */ |
- |
- /* |
- ** ANSI X9.62, Section 5.4.2, Step 4 |
- ** |
- ** u1 = ((HASH(M')) * c) mod n |
- */ |
- SECITEM_TO_MPINT(*digest, &u1); /* u1 = HASH(M) */ |
- |
- /* In the definition of EC signing, digests are truncated |
- * to the length of n in bits. |
- * (see SEC 1 "Elliptic Curve Digit Signature Algorithm" section 4.1.*/ |
- CHECK_MPI_OK( (obits = mpl_significant_bits(&n)) ); |
- if (digest->len*8 > obits) { /* u1 = HASH(M') */ |
- mpl_rsh(&u1,&u1,digest->len*8 - obits); |
- } |
- |
-#if EC_DEBUG |
- mp_todecimal(&r_, mpstr); |
- printf("r_: %s (dec)\n", mpstr); |
- mp_todecimal(&s_, mpstr); |
- printf("s_: %s (dec)\n", mpstr); |
- mp_todecimal(&c, mpstr); |
- printf("c : %s (dec)\n", mpstr); |
- mp_todecimal(&u1, mpstr); |
- printf("digest: %s (dec)\n", mpstr); |
-#endif |
- |
- CHECK_MPI_OK( mp_mulmod(&u1, &c, &n, &u1) ); /* u1 = u1 * c mod n */ |
- |
- /* |
- ** ANSI X9.62, Section 5.4.2, Step 4 |
- ** |
- ** u2 = ((r') * c) mod n |
- */ |
- CHECK_MPI_OK( mp_mulmod(&r_, &c, &n, &u2) ); |
- |
- /* |
- ** ANSI X9.62, Section 5.4.3, Step 1 |
- ** |
- ** Compute u1*G + u2*Q |
- ** Here, A = u1.G B = u2.Q and C = A + B |
- ** If the result, C, is the point at infinity, reject the signature |
- */ |
- if (ec_points_mul(ecParams, &u1, &u2, &key->publicValue, &pointC) |
- != SECSuccess) { |
- rv = SECFailure; |
- goto cleanup; |
- } |
- if (ec_point_at_infinity(&pointC)) { |
- PORT_SetError(SEC_ERROR_BAD_SIGNATURE); |
- rv = SECFailure; |
- goto cleanup; |
- } |
- |
- CHECK_MPI_OK( mp_read_unsigned_octets(&x1, pointC.data + 1, flen) ); |
- |
- /* |
- ** ANSI X9.62, Section 5.4.4, Step 2 |
- ** |
- ** v = x1 mod n |
- */ |
- CHECK_MPI_OK( mp_mod(&x1, &n, &v) ); |
- |
-#if EC_DEBUG |
- mp_todecimal(&r_, mpstr); |
- printf("r_: %s (dec)\n", mpstr); |
- mp_todecimal(&v, mpstr); |
- printf("v : %s (dec)\n", mpstr); |
-#endif |
- |
- /* |
- ** ANSI X9.62, Section 5.4.4, Step 3 |
- ** |
- ** Verification: v == r' |
- */ |
- if (mp_cmp(&v, &r_)) { |
- PORT_SetError(SEC_ERROR_BAD_SIGNATURE); |
- rv = SECFailure; /* Signature failed to verify. */ |
- } else { |
- rv = SECSuccess; /* Signature verified. */ |
- } |
- |
-#if EC_DEBUG |
- mp_todecimal(&u1, mpstr); |
- printf("u1: %s (dec)\n", mpstr); |
- mp_todecimal(&u2, mpstr); |
- printf("u2: %s (dec)\n", mpstr); |
- mp_tohex(&x1, mpstr); |
- printf("x1: %s\n", mpstr); |
- mp_todecimal(&v, mpstr); |
- printf("v : %s (dec)\n", mpstr); |
-#endif |
- |
-cleanup: |
- mp_clear(&r_); |
- mp_clear(&s_); |
- mp_clear(&c); |
- mp_clear(&u1); |
- mp_clear(&u2); |
- mp_clear(&x1); |
- mp_clear(&v); |
- mp_clear(&n); |
- |
- if (pointC.data) SECITEM_FreeItem(&pointC, PR_FALSE); |
- if (err) { |
- MP_TO_SEC_ERROR(err); |
- rv = SECFailure; |
- } |
- |
-#if EC_DEBUG |
- printf("ECDSA verification %s\n", |
- (rv == SECSuccess) ? "succeeded" : "failed"); |
-#endif |
-#else |
- PORT_SetError(SEC_ERROR_UNSUPPORTED_KEYALG); |
-#endif /* NSS_ENABLE_ECC */ |
- |
- return rv; |
-} |
- |