From 5470898e37875e2cf29019c4e66322f8a4ba5e69 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= Date: Wed, 26 Jul 2023 15:38:36 +0200 Subject: [PATCH] Move code around again MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Manuel Pégourié-Gonnard --- library/pkparse.c | 566 ++++++++++++++++++++++++---------------------- 1 file changed, 292 insertions(+), 274 deletions(-) diff --git a/library/pkparse.c b/library/pkparse.c index 98094a36fe..5a35c43fbb 100644 --- a/library/pkparse.c +++ b/library/pkparse.c @@ -57,56 +57,274 @@ #if defined(MBEDTLS_PK_HAVE_ECC_KEYS) -/* Helper for Montgomery curves */ -#if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES) -#define MBEDTLS_PK_IS_RFC8410_GROUP_ID(id) \ - ((id == MBEDTLS_ECP_DP_CURVE25519) || (id == MBEDTLS_ECP_DP_CURVE448)) -#endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */ - -/* Minimally parse an ECParameters buffer to and mbedtls_asn1_buf +/*********************************************************************** * - * ECParameters ::= CHOICE { - * namedCurve OBJECT IDENTIFIER - * specifiedCurve SpecifiedECDomain -- = SEQUENCE { ... } - * -- implicitCurve NULL - * } + * ECC setters + * + * 1. This is an abstraction layer around MBEDTLS_PK_USE_PSA_EC_DATA: + * this macro will not appear outside this section. + * 2. All inputs are raw: no metadata, no ASN.1 until the next section. + * + **********************************************************************/ + +/* + * Set the group used by this key. */ -static int pk_get_ecparams(unsigned char **p, const unsigned char *end, - mbedtls_asn1_buf *params) +static int pk_ecc_set_group(mbedtls_pk_context *pk, mbedtls_ecp_group_id grp_id) +{ +#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) + size_t ec_bits; + psa_ecc_family_t ec_family = mbedtls_ecc_group_to_psa(grp_id, &ec_bits); + + /* group may already be initialized; if so, make sure IDs match */ + if ((pk->ec_family != 0 && pk->ec_family != ec_family) || + (pk->ec_bits != 0 && pk->ec_bits != ec_bits)) { + return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT; + } + + /* set group */ + pk->ec_family = ec_family; + pk->ec_bits = ec_bits; + + return 0; +#else /* MBEDTLS_PK_USE_PSA_EC_DATA */ + mbedtls_ecp_keypair *ecp = mbedtls_pk_ec_rw(*pk); + + /* grp may already be initialized; if so, make sure IDs match */ + if (mbedtls_pk_ec_ro(*pk)->grp.id != MBEDTLS_ECP_DP_NONE && + mbedtls_pk_ec_ro(*pk)->grp.id != grp_id) { + return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT; + } + + /* set group */ + return mbedtls_ecp_group_load(&(ecp->grp), grp_id); +#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ +} + +/* + * Set the private key material + * + * Must have already set the group with pk_ecc_set_group(). + * + * The 'key' argument points to the raw private key (no ASN.1 wrapping). + */ +static int pk_ecc_set_key(mbedtls_pk_context *pk, + unsigned char *key, size_t len) +{ +#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) + psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT; + psa_status_t status; + + psa_set_key_type(&attributes, PSA_KEY_TYPE_ECC_KEY_PAIR(pk->ec_family)); + psa_set_key_algorithm(&attributes, PSA_ALG_ECDH); + psa_key_usage_t flags = PSA_KEY_USAGE_EXPORT | PSA_KEY_USAGE_DERIVE; + /* Montgomery allows only ECDH, others ECDSA too */ + if (pk->ec_family != PSA_ECC_FAMILY_MONTGOMERY) { + flags |= PSA_KEY_USAGE_SIGN_HASH | PSA_KEY_USAGE_SIGN_MESSAGE; + psa_set_key_enrollment_algorithm(&attributes, + MBEDTLS_PK_PSA_ALG_ECDSA_MAYBE_DET(PSA_ALG_ANY_HASH)); + } + psa_set_key_usage_flags(&attributes, flags); + + status = psa_import_key(&attributes, key, len, &pk->priv_id); + return psa_pk_status_to_mbedtls(status); + +#else /* MBEDTLS_PK_USE_PSA_EC_DATA */ + + mbedtls_ecp_keypair *eck = mbedtls_pk_ec_rw(*pk); + int ret = mbedtls_ecp_read_key(eck->grp.id, eck, key, len); + if (ret != 0) { + return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret); + } + return 0; +#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ +} + +/* + * Helper function for deriving a public key from its private counterpart. + * + * Note: the private key information is always available from pk, + * however for convenience the serialized version is also passed, + * as it's available at each calling site, and useful in some configs + * (as otherwise we're have to re-serialize it from the pk context). + */ +static int pk_derive_public_key(mbedtls_pk_context *pk, + const unsigned char *d, size_t d_len, + int (*f_rng)(void *, unsigned char *, size_t), void *p_rng) +{ +#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) + psa_status_t status; + (void) f_rng; + (void) p_rng; + (void) d; + (void) d_len; + + status = psa_export_public_key(pk->priv_id, pk->pub_raw, sizeof(pk->pub_raw), + &pk->pub_raw_len); + return psa_pk_status_to_mbedtls(status); +#elif defined(MBEDTLS_USE_PSA_CRYPTO) /* && !MBEDTLS_PK_USE_PSA_EC_DATA */ + int ret; + psa_status_t status; + (void) f_rng; + (void) p_rng; + + mbedtls_ecp_keypair *eck = (mbedtls_ecp_keypair *) pk->pk_ctx; + unsigned char key_buf[MBEDTLS_PSA_MAX_EC_PUBKEY_LENGTH]; + size_t key_len; + mbedtls_svc_key_id_t key_id = MBEDTLS_SVC_KEY_ID_INIT; + psa_key_attributes_t key_attr = PSA_KEY_ATTRIBUTES_INIT; + size_t curve_bits; + psa_ecc_family_t curve = mbedtls_ecc_group_to_psa(eck->grp.id, &curve_bits); + psa_status_t destruction_status; + + psa_set_key_type(&key_attr, PSA_KEY_TYPE_ECC_KEY_PAIR(curve)); + psa_set_key_usage_flags(&key_attr, PSA_KEY_USAGE_EXPORT); + + status = psa_import_key(&key_attr, d, d_len, &key_id); + ret = psa_pk_status_to_mbedtls(status); + if (ret != 0) { + return ret; + } + + status = psa_export_public_key(key_id, key_buf, sizeof(key_buf), &key_len); + ret = psa_pk_status_to_mbedtls(status); + destruction_status = psa_destroy_key(key_id); + if (ret != 0) { + return ret; + } else if (destruction_status != PSA_SUCCESS) { + return psa_pk_status_to_mbedtls(destruction_status); + } + return mbedtls_ecp_point_read_binary(&eck->grp, &eck->Q, key_buf, key_len); +#else /* MBEDTLS_USE_PSA_CRYPTO */ + mbedtls_ecp_keypair *eck = (mbedtls_ecp_keypair *) pk->pk_ctx; + (void) d; + (void) d_len; + + return mbedtls_ecp_mul(&eck->grp, &eck->Q, &eck->d, &eck->grp.G, f_rng, p_rng); +#endif /* MBEDTLS_USE_PSA_CRYPTO */ +} + +#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) +/* + * Create a temporary ecp_keypair for converting an EC point in compressed + * format to an uncompressed one + * + * Consumes everything or fails - inherited from + * mbedtls_ecp_point_read_binary(). + */ +static int pk_ecc_read_compressed(mbedtls_pk_context *pk, + const unsigned char *in_start, size_t in_len, + unsigned char *out_buf, size_t out_buf_size, + size_t *out_buf_len) +{ +#if defined(MBEDTLS_PK_PARSE_EC_COMPRESSED) + mbedtls_ecp_keypair ecp_key; + mbedtls_ecp_group_id ecp_group_id; + int ret; + + ecp_group_id = mbedtls_ecc_group_of_psa(pk->ec_family, pk->ec_bits, 0); + + mbedtls_ecp_keypair_init(&ecp_key); + ret = mbedtls_ecp_group_load(&(ecp_key.grp), ecp_group_id); + if (ret != 0) { + return ret; + } + ret = mbedtls_ecp_point_read_binary(&(ecp_key.grp), &ecp_key.Q, + in_start, in_len); + if (ret != 0) { + goto exit; + } + ret = mbedtls_ecp_point_write_binary(&(ecp_key.grp), &ecp_key.Q, + MBEDTLS_ECP_PF_UNCOMPRESSED, + out_buf_len, out_buf, out_buf_size); + +exit: + mbedtls_ecp_keypair_free(&ecp_key); + return ret; +#else /* MBEDTLS_PK_PARSE_EC_COMPRESSED */ + return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE; +#endif /* MBEDTLS_PK_PARSE_EC_COMPRESSED */ +} +#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ + +/* + * EC public key is an EC point + * + * The caller is responsible for clearing the structure upon failure if + * desired. Take care to pass along the possible ECP_FEATURE_UNAVAILABLE + * return code of mbedtls_ecp_point_read_binary() and leave p in a usable state. + */ +static int pk_get_ecpubkey(unsigned char **p, const unsigned char *end, + mbedtls_pk_context *pk) { int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; - if (end - *p < 1) { - return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, - MBEDTLS_ERR_ASN1_OUT_OF_DATA); +#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) + mbedtls_svc_key_id_t key; + psa_key_attributes_t key_attrs = PSA_KEY_ATTRIBUTES_INIT; + size_t len = (size_t) (end - *p); + + if (len > PSA_EXPORT_PUBLIC_KEY_MAX_SIZE) { + return MBEDTLS_ERR_PK_BAD_INPUT_DATA; } - /* Tag may be either OID or SEQUENCE */ - params->tag = **p; - if (params->tag != MBEDTLS_ASN1_OID -#if defined(MBEDTLS_PK_PARSE_EC_EXTENDED) - && params->tag != (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE) -#endif - ) { - return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, - MBEDTLS_ERR_ASN1_UNEXPECTED_TAG); + if ((**p == 0x02) || (**p == 0x03)) { + /* Compressed format, not supported by PSA Crypto. + * Try converting using functions from ECP_LIGHT. */ + ret = pk_ecc_read_compressed(pk, *p, len, + pk->pub_raw, + PSA_EXPORT_PUBLIC_KEY_MAX_SIZE, + &pk->pub_raw_len); + if (ret != 0) { + return ret; + } + } else { + /* Uncompressed format */ + if (len > MBEDTLS_PK_MAX_EC_PUBKEY_RAW_LEN) { + return MBEDTLS_ERR_PK_BUFFER_TOO_SMALL; + } + memcpy(pk->pub_raw, *p, len); + pk->pub_raw_len = len; } - if ((ret = mbedtls_asn1_get_tag(p, end, ¶ms->len, params->tag)) != 0) { - return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret); + /* Validate the key by trying to importing it */ + psa_set_key_usage_flags(&key_attrs, 0); + psa_set_key_algorithm(&key_attrs, PSA_ALG_ECDSA_ANY); + psa_set_key_type(&key_attrs, PSA_KEY_TYPE_ECC_PUBLIC_KEY(pk->ec_family)); + psa_set_key_bits(&key_attrs, pk->ec_bits); + + if ((psa_import_key(&key_attrs, pk->pub_raw, pk->pub_raw_len, + &key) != PSA_SUCCESS) || + (psa_destroy_key(key) != PSA_SUCCESS)) { + mbedtls_platform_zeroize(pk->pub_raw, MBEDTLS_PK_MAX_EC_PUBKEY_RAW_LEN); + pk->pub_raw_len = 0; + return MBEDTLS_ERR_PK_BAD_INPUT_DATA; } - - params->p = *p; - *p += params->len; - - if (*p != end) { - return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, - MBEDTLS_ERR_ASN1_LENGTH_MISMATCH); + ret = 0; +#else /* MBEDTLS_PK_USE_PSA_EC_DATA */ + mbedtls_ecp_keypair *ec_key = (mbedtls_ecp_keypair *) pk->pk_ctx; + if ((ret = mbedtls_ecp_point_read_binary(&ec_key->grp, &ec_key->Q, + (const unsigned char *) *p, + end - *p)) == 0) { + ret = mbedtls_ecp_check_pubkey(&ec_key->grp, &ec_key->Q); } +#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ - return 0; + /* + * We know mbedtls_ecp_point_read_binary and pk_ecc_read_compressed either + * consumed all bytes or failed, and memcpy consumed all bytes too. + */ + *p = (unsigned char *) end; + + return ret; } +/*********************************************************************** + * + * Unsorted (yet!) from this point on until the next section header + * + **********************************************************************/ + #if defined(MBEDTLS_PK_PARSE_EC_EXTENDED) /* * Parse a SpecifiedECDomain (SEC 1 C.2) and (mostly) fill the group with it. @@ -352,77 +570,49 @@ cleanup: } #endif /* MBEDTLS_PK_PARSE_EC_EXTENDED */ -/* - * Set the group used by this key. - */ -static int pk_ecc_set_group(mbedtls_pk_context *pk, mbedtls_ecp_group_id grp_id) -{ -#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) - size_t ec_bits; - psa_ecc_family_t ec_family = mbedtls_ecc_group_to_psa(grp_id, &ec_bits); - /* group may already be initialized; if so, make sure IDs match */ - if ((pk->ec_family != 0 && pk->ec_family != ec_family) || - (pk->ec_bits != 0 && pk->ec_bits != ec_bits)) { - return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT; - } - - /* set group */ - pk->ec_family = ec_family; - pk->ec_bits = ec_bits; - - return 0; -#else /* MBEDTLS_PK_USE_PSA_EC_DATA */ - mbedtls_ecp_keypair *ecp = mbedtls_pk_ec_rw(*pk); - - /* grp may already be initialized; if so, make sure IDs match */ - if (mbedtls_pk_ec_ro(*pk)->grp.id != MBEDTLS_ECP_DP_NONE && - mbedtls_pk_ec_ro(*pk)->grp.id != grp_id) { - return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT; - } - - /* set group */ - return mbedtls_ecp_group_load(&(ecp->grp), grp_id); -#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ -} - -/* - * Set the private key material +/* Minimally parse an ECParameters buffer to and mbedtls_asn1_buf * - * Must have already set the group with pk_ecc_set_group(). - * - * The 'key' argument points to the raw private key (no ASN.1 wrapping). + * ECParameters ::= CHOICE { + * namedCurve OBJECT IDENTIFIER + * specifiedCurve SpecifiedECDomain -- = SEQUENCE { ... } + * -- implicitCurve NULL + * } */ -static int pk_ecc_set_key(mbedtls_pk_context *pk, - unsigned char *key, size_t len) +static int pk_get_ecparams(unsigned char **p, const unsigned char *end, + mbedtls_asn1_buf *params) { -#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) - psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT; - psa_status_t status; + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; - psa_set_key_type(&attributes, PSA_KEY_TYPE_ECC_KEY_PAIR(pk->ec_family)); - psa_set_key_algorithm(&attributes, PSA_ALG_ECDH); - psa_key_usage_t flags = PSA_KEY_USAGE_EXPORT | PSA_KEY_USAGE_DERIVE; - /* Montgomery allows only ECDH, others ECDSA too */ - if (pk->ec_family != PSA_ECC_FAMILY_MONTGOMERY) { - flags |= PSA_KEY_USAGE_SIGN_HASH | PSA_KEY_USAGE_SIGN_MESSAGE; - psa_set_key_enrollment_algorithm(&attributes, - MBEDTLS_PK_PSA_ALG_ECDSA_MAYBE_DET(PSA_ALG_ANY_HASH)); + if (end - *p < 1) { + return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, + MBEDTLS_ERR_ASN1_OUT_OF_DATA); } - psa_set_key_usage_flags(&attributes, flags); - status = psa_import_key(&attributes, key, len, &pk->priv_id); - return psa_pk_status_to_mbedtls(status); + /* Tag may be either OID or SEQUENCE */ + params->tag = **p; + if (params->tag != MBEDTLS_ASN1_OID +#if defined(MBEDTLS_PK_PARSE_EC_EXTENDED) + && params->tag != (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE) +#endif + ) { + return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, + MBEDTLS_ERR_ASN1_UNEXPECTED_TAG); + } -#else /* MBEDTLS_PK_USE_PSA_EC_DATA */ - - mbedtls_ecp_keypair *eck = mbedtls_pk_ec_rw(*pk); - int ret = mbedtls_ecp_read_key(eck->grp.id, eck, key, len); - if (ret != 0) { + if ((ret = mbedtls_asn1_get_tag(p, end, ¶ms->len, params->tag)) != 0) { return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret); } + + params->p = *p; + *p += params->len; + + if (*p != end) { + return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, + MBEDTLS_ERR_ASN1_LENGTH_MISMATCH); + } + return 0; -#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ } /* @@ -455,70 +645,6 @@ static int pk_use_ecparams(const mbedtls_asn1_buf *params, mbedtls_pk_context *p return pk_ecc_set_group(pk, grp_id); } -/* - * Helper function for deriving a public key from its private counterpart. - * - * Note: the private key information is always available from pk, - * however for convenience the serialized version is also passed, - * as it's available at each calling site, and useful in some configs - * (as otherwise we're have to re-serialize it from the pk context). - */ -static int pk_derive_public_key(mbedtls_pk_context *pk, - const unsigned char *d, size_t d_len, - int (*f_rng)(void *, unsigned char *, size_t), void *p_rng) -{ -#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) - psa_status_t status; - (void) f_rng; - (void) p_rng; - (void) d; - (void) d_len; - - status = psa_export_public_key(pk->priv_id, pk->pub_raw, sizeof(pk->pub_raw), - &pk->pub_raw_len); - return psa_pk_status_to_mbedtls(status); -#elif defined(MBEDTLS_USE_PSA_CRYPTO) /* && !MBEDTLS_PK_USE_PSA_EC_DATA */ - int ret; - psa_status_t status; - (void) f_rng; - (void) p_rng; - - mbedtls_ecp_keypair *eck = (mbedtls_ecp_keypair *) pk->pk_ctx; - unsigned char key_buf[MBEDTLS_PSA_MAX_EC_PUBKEY_LENGTH]; - size_t key_len; - mbedtls_svc_key_id_t key_id = MBEDTLS_SVC_KEY_ID_INIT; - psa_key_attributes_t key_attr = PSA_KEY_ATTRIBUTES_INIT; - size_t curve_bits; - psa_ecc_family_t curve = mbedtls_ecc_group_to_psa(eck->grp.id, &curve_bits); - psa_status_t destruction_status; - - psa_set_key_type(&key_attr, PSA_KEY_TYPE_ECC_KEY_PAIR(curve)); - psa_set_key_usage_flags(&key_attr, PSA_KEY_USAGE_EXPORT); - - status = psa_import_key(&key_attr, d, d_len, &key_id); - ret = psa_pk_status_to_mbedtls(status); - if (ret != 0) { - return ret; - } - - status = psa_export_public_key(key_id, key_buf, sizeof(key_buf), &key_len); - ret = psa_pk_status_to_mbedtls(status); - destruction_status = psa_destroy_key(key_id); - if (ret != 0) { - return ret; - } else if (destruction_status != PSA_SUCCESS) { - return psa_pk_status_to_mbedtls(destruction_status); - } - return mbedtls_ecp_point_read_binary(&eck->grp, &eck->Q, key_buf, key_len); -#else /* MBEDTLS_USE_PSA_CRYPTO */ - mbedtls_ecp_keypair *eck = (mbedtls_ecp_keypair *) pk->pk_ctx; - (void) d; - (void) d_len; - - return mbedtls_ecp_mul(&eck->grp, &eck->Q, &eck->d, &eck->grp.G, f_rng, p_rng); -#endif /* MBEDTLS_USE_PSA_CRYPTO */ -} - #if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES) /* @@ -574,120 +700,6 @@ static int pk_parse_key_rfc8410_der(mbedtls_pk_context *pk, } #endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */ -#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) -/* - * Create a temporary ecp_keypair for converting an EC point in compressed - * format to an uncompressed one - * - * Consumes everything or fails - inherited from - * mbedtls_ecp_point_read_binary(). - */ -static int pk_ecc_read_compressed(mbedtls_pk_context *pk, - const unsigned char *in_start, size_t in_len, - unsigned char *out_buf, size_t out_buf_size, - size_t *out_buf_len) -{ -#if defined(MBEDTLS_PK_PARSE_EC_COMPRESSED) - mbedtls_ecp_keypair ecp_key; - mbedtls_ecp_group_id ecp_group_id; - int ret; - - ecp_group_id = mbedtls_ecc_group_of_psa(pk->ec_family, pk->ec_bits, 0); - - mbedtls_ecp_keypair_init(&ecp_key); - ret = mbedtls_ecp_group_load(&(ecp_key.grp), ecp_group_id); - if (ret != 0) { - return ret; - } - ret = mbedtls_ecp_point_read_binary(&(ecp_key.grp), &ecp_key.Q, - in_start, in_len); - if (ret != 0) { - goto exit; - } - ret = mbedtls_ecp_point_write_binary(&(ecp_key.grp), &ecp_key.Q, - MBEDTLS_ECP_PF_UNCOMPRESSED, - out_buf_len, out_buf, out_buf_size); - -exit: - mbedtls_ecp_keypair_free(&ecp_key); - return ret; -#else /* MBEDTLS_PK_PARSE_EC_COMPRESSED */ - return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE; -#endif /* MBEDTLS_PK_PARSE_EC_COMPRESSED */ -} -#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ - -/* - * EC public key is an EC point - * - * The caller is responsible for clearing the structure upon failure if - * desired. Take care to pass along the possible ECP_FEATURE_UNAVAILABLE - * return code of mbedtls_ecp_point_read_binary() and leave p in a usable state. - */ -static int pk_get_ecpubkey(unsigned char **p, const unsigned char *end, - mbedtls_pk_context *pk) -{ - int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; - -#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) - mbedtls_svc_key_id_t key; - psa_key_attributes_t key_attrs = PSA_KEY_ATTRIBUTES_INIT; - size_t len = (size_t) (end - *p); - - if (len > PSA_EXPORT_PUBLIC_KEY_MAX_SIZE) { - return MBEDTLS_ERR_PK_BAD_INPUT_DATA; - } - - if ((**p == 0x02) || (**p == 0x03)) { - /* Compressed format, not supported by PSA Crypto. - * Try converting using functions from ECP_LIGHT. */ - ret = pk_ecc_read_compressed(pk, *p, len, - pk->pub_raw, - PSA_EXPORT_PUBLIC_KEY_MAX_SIZE, - &pk->pub_raw_len); - if (ret != 0) { - return ret; - } - } else { - /* Uncompressed format */ - if (len > MBEDTLS_PK_MAX_EC_PUBKEY_RAW_LEN) { - return MBEDTLS_ERR_PK_BUFFER_TOO_SMALL; - } - memcpy(pk->pub_raw, *p, len); - pk->pub_raw_len = len; - } - - /* Validate the key by trying to importing it */ - psa_set_key_usage_flags(&key_attrs, 0); - psa_set_key_algorithm(&key_attrs, PSA_ALG_ECDSA_ANY); - psa_set_key_type(&key_attrs, PSA_KEY_TYPE_ECC_PUBLIC_KEY(pk->ec_family)); - psa_set_key_bits(&key_attrs, pk->ec_bits); - - if ((psa_import_key(&key_attrs, pk->pub_raw, pk->pub_raw_len, - &key) != PSA_SUCCESS) || - (psa_destroy_key(key) != PSA_SUCCESS)) { - mbedtls_platform_zeroize(pk->pub_raw, MBEDTLS_PK_MAX_EC_PUBKEY_RAW_LEN); - pk->pub_raw_len = 0; - return MBEDTLS_ERR_PK_BAD_INPUT_DATA; - } - ret = 0; -#else /* MBEDTLS_PK_USE_PSA_EC_DATA */ - mbedtls_ecp_keypair *ec_key = (mbedtls_ecp_keypair *) pk->pk_ctx; - if ((ret = mbedtls_ecp_point_read_binary(&ec_key->grp, &ec_key->Q, - (const unsigned char *) *p, - end - *p)) == 0) { - ret = mbedtls_ecp_check_pubkey(&ec_key->grp, &ec_key->Q); - } -#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ - - /* - * We know mbedtls_ecp_point_read_binary and pk_ecc_read_compressed either - * consumed all bytes or failed, and memcpy consumed all bytes too. - */ - *p = (unsigned char *) end; - - return ret; -} #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */ #if defined(MBEDTLS_RSA_C) @@ -799,6 +811,12 @@ static int pk_get_pk_alg(unsigned char **p, return 0; } +/* Helper for Montgomery curves */ +#if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES) +#define MBEDTLS_PK_IS_RFC8410_GROUP_ID(id) \ + ((id == MBEDTLS_ECP_DP_CURVE25519) || (id == MBEDTLS_ECP_DP_CURVE448)) +#endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */ + /* * SubjectPublicKeyInfo ::= SEQUENCE { * algorithm AlgorithmIdentifier,