diff options
| -rw-r--r-- | asn1.c | 319 | ||||
| -rw-r--r-- | asn1_internal.h | 18 |
2 files changed, 335 insertions, 2 deletions
@@ -55,6 +55,8 @@ #include "asn1_internal.h" +#define INIT_FP_INT {{{0}}} + /* * Encode tag and length fields of an ASN.1 object. * @@ -153,7 +155,7 @@ hal_error_t hal_asn1_encode_integer(const fp_int * const bn, } /* - * Encode a public key into an RFC 5280 SubjectPublicKeyInfo. + * Encode a public key into a X.509 SubjectPublicKeyInfo (RFC 5280). */ hal_error_t hal_asn1_encode_spki(const uint8_t * const alg_oid, const size_t alg_oid_len, @@ -234,6 +236,164 @@ hal_error_t hal_asn1_encode_spki(const uint8_t * const alg_oid, const size_t a } /* + * Encode a PKCS #8 PrivateKeyInfo (RFC 5208). + */ + +hal_error_t hal_asn1_encode_pkcs8_privatekeyinfo(const uint8_t * const alg_oid, const size_t alg_oid_len, + const uint8_t * const curve_oid, const size_t curve_oid_len, + const uint8_t * const privkey, const size_t privkey_len, + uint8_t *der, size_t *der_len, const size_t der_max) +{ + if (alg_oid == NULL || alg_oid_len == 0 || privkey_len == 0 || + (der != NULL && privkey == NULL) || (curve_oid == NULL && curve_oid_len != 0)) + return HAL_ERROR_BAD_ARGUMENTS; + + fp_int version[1] = INIT_FP_INT; + + hal_error_t err; + + size_t version_len, hlen, hlen_pkcs8, hlen_algid, hlen_alg, hlen_curve = 0, hlen_oct; + + if ((err = hal_asn1_encode_integer(version, NULL, &version_len, 0)) != HAL_OK || + (err = hal_asn1_encode_header(ASN1_OBJECT_IDENTIFIER, alg_oid_len, NULL, &hlen_alg, 0)) != HAL_OK || + (err = hal_asn1_encode_header(ASN1_OCTET_STRING, privkey_len, NULL, &hlen_oct, 0)) != HAL_OK) + return err; + + if (curve_oid != NULL && + (err = hal_asn1_encode_header(ASN1_OBJECT_IDENTIFIER, curve_oid_len, NULL, &hlen_curve, 0)) != HAL_OK) + return err; + + const size_t algid_len = hlen_alg + alg_oid_len + hlen_curve + curve_oid_len; + + if ((err = hal_asn1_encode_header(ASN1_SEQUENCE, algid_len, NULL, &hlen_algid, 0)) != HAL_OK) + return err; + + const size_t vlen = version_len + hlen_algid + hlen_alg + alg_oid_len + hlen_curve + curve_oid_len + hlen_oct + privkey_len; + + if ((err = hal_asn1_encode_header(ASN1_SEQUENCE, vlen, NULL, &hlen_pkcs8, 0)) != HAL_OK) + return err; + + /* + * Handle privkey early, in case it was staged into our output buffer. + */ + if (der != NULL && hlen_pkcs8 + vlen <= der_max) + memmove(der + hlen_pkcs8 + vlen - privkey_len, privkey, privkey_len); + + err = hal_asn1_encode_header(ASN1_SEQUENCE, vlen, der, &hlen, der_max); + + if (der_len != NULL) + *der_len = hlen + vlen; + + if (der == NULL || err != HAL_OK) + return err; + + uint8_t *d = der + hlen; + memset(d, 0, vlen - privkey_len); + + if ((err = hal_asn1_encode_integer(version, d, NULL, der + der_max - d)) != HAL_OK) + return err; + d += version_len; + + if ((err = hal_asn1_encode_header(ASN1_SEQUENCE, algid_len, d, &hlen, der + der_max - d)) != HAL_OK) + return err; + d += hlen; + + if ((err = hal_asn1_encode_header(ASN1_OBJECT_IDENTIFIER, alg_oid_len, d, &hlen, der + der_max - d)) != HAL_OK) + return err; + d += hlen; + memcpy(d, alg_oid, alg_oid_len); + d += alg_oid_len; + + if (curve_oid != NULL && + (err = hal_asn1_encode_header(ASN1_OBJECT_IDENTIFIER, curve_oid_len, d, &hlen, der + der_max - d)) != HAL_OK) + return err; + d += hlen; + if (curve_oid != NULL) + memcpy(d, curve_oid, curve_oid_len); + d += curve_oid_len; + + if ((err = hal_asn1_encode_header(ASN1_OCTET_STRING, privkey_len, d, &hlen, der + der_max - d)) != HAL_OK) + return err; + d += hlen; + + d += privkey_len; /* privkey handled early, above. */ + + assert(d == der + hlen_pkcs8 + vlen); + assert(d <= der + der_max); + + return HAL_OK; +} + +/* + * Encode a PKCS #8 EncryptedPrivateKeyInfo (RFC 5208). + */ + +hal_error_t hal_asn1_encode_pkcs8_encryptedprivatekeyinfo(const uint8_t * const alg_oid, const size_t alg_oid_len, + const uint8_t * const data, const size_t data_len, + uint8_t *der, size_t *der_len, const size_t der_max) +{ + if (alg_oid == NULL || alg_oid_len == 0 || data_len == 0 || (der != NULL && data == NULL)) + return HAL_ERROR_BAD_ARGUMENTS; + + hal_error_t err; + + size_t hlen, hlen_pkcs8, hlen_algid, hlen_alg, hlen_oct; + + if ((err = hal_asn1_encode_header(ASN1_OBJECT_IDENTIFIER, alg_oid_len, NULL, &hlen_alg, 0)) != HAL_OK || + (err = hal_asn1_encode_header(ASN1_OCTET_STRING, data_len, NULL, &hlen_oct, 0)) != HAL_OK) + return err; + + const size_t algid_len = hlen_alg + alg_oid_len; + + if ((err = hal_asn1_encode_header(ASN1_SEQUENCE, algid_len, NULL, &hlen_algid, 0)) != HAL_OK) + return err; + + const size_t vlen = hlen_algid + hlen_alg + alg_oid_len + hlen_oct + data_len; + + if ((err = hal_asn1_encode_header(ASN1_SEQUENCE, vlen, NULL, &hlen_pkcs8, 0)) != HAL_OK) + return err; + + /* + * Handle data early, in case it was staged into our output buffer. + */ + if (der != NULL && hlen_pkcs8 + vlen <= der_max) + memmove(der + hlen_pkcs8 + vlen - data_len, data, data_len); + + err = hal_asn1_encode_header(ASN1_SEQUENCE, vlen, der, &hlen, der_max); + + if (der_len != NULL) + *der_len = hlen + vlen; + + if (der == NULL || err != HAL_OK) + return err; + + uint8_t *d = der + hlen; + memset(d, 0, vlen - data_len); + + if ((err = hal_asn1_encode_header(ASN1_SEQUENCE, algid_len, d, &hlen, der + der_max - d)) != HAL_OK) + return err; + d += hlen; + + if ((err = hal_asn1_encode_header(ASN1_OBJECT_IDENTIFIER, alg_oid_len, d, &hlen, der + der_max - d)) != HAL_OK) + return err; + d += hlen; + memcpy(d, alg_oid, alg_oid_len); + d += alg_oid_len; + + if ((err = hal_asn1_encode_header(ASN1_OCTET_STRING, data_len, d, &hlen, der + der_max - d)) != HAL_OK) + return err; + d += hlen; + + d += data_len; /* data handled early, above. */ + + assert(d == der + hlen_pkcs8 + vlen); + assert(d <= der + der_max); + + return HAL_OK; +} + + +/* * Parse tag and length of an ASN.1 object. Tag must match value * specified by the caller. On success, sets hlen and vlen to lengths * of header and value, respectively. @@ -300,7 +460,7 @@ hal_error_t hal_asn1_decode_integer(fp_int *bn, } /* - * Decode a public key from an RFC 5280 SubjectPublicKeyInfo. + * Decode a public key from a X.509 SubjectPublicKeyInfo (RFC 5280). */ hal_error_t hal_asn1_decode_spki(const uint8_t **alg_oid, size_t *alg_oid_len, @@ -322,6 +482,9 @@ hal_error_t hal_asn1_decode_spki(const uint8_t **alg_oid, size_t *alg_oid_len, return err; d += hlen; + if (hlen + vlen != der_len) + return HAL_ERROR_ASN1_PARSE_FAILED; + if ((err = hal_asn1_decode_header(ASN1_SEQUENCE, d, der_end - d, &hlen, &vlen)) != HAL_OK) return err; d += hlen; @@ -385,6 +548,158 @@ hal_error_t hal_asn1_decode_spki(const uint8_t **alg_oid, size_t *alg_oid_len, } /* + * Decode a private key from a PKCS #8 PrivateKeyInfo (RFC 5208). + */ + +hal_error_t hal_asn1_decode_pkcs8_privatekeyinfo(const uint8_t **alg_oid, size_t *alg_oid_len, + const uint8_t **curve_oid, size_t *curve_oid_len, + const uint8_t **privkey, size_t *privkey_len, + const uint8_t *const der, const size_t der_len) +{ + if (alg_oid == NULL || alg_oid_len == NULL || curve_oid == NULL || curve_oid_len == NULL || + privkey == NULL || privkey_len == NULL || der == NULL) + return HAL_ERROR_BAD_ARGUMENTS; + + const uint8_t * const der_end = der + der_len; + const uint8_t *d = der; + + fp_int version[1] = INIT_FP_INT; + size_t hlen, vlen; + hal_error_t err; + + if ((err = hal_asn1_decode_header(ASN1_SEQUENCE, d, der_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + + if (hlen + vlen != der_len) + return HAL_ERROR_ASN1_PARSE_FAILED; + + if ((err - hal_asn1_decode_integer(version, d, &hlen, der_end - d)) != HAL_OK) + return err; + if (!fp_iszero(version)) + return HAL_ERROR_ASN1_PARSE_FAILED; + d += hlen; + + if ((err = hal_asn1_decode_header(ASN1_SEQUENCE, d, der_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + + const uint8_t * const algid_end = d + vlen; + + if ((err = hal_asn1_decode_header(ASN1_OBJECT_IDENTIFIER, d, algid_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + if (vlen > algid_end - d) + return HAL_ERROR_ASN1_PARSE_FAILED; + *alg_oid = d; + *alg_oid_len = vlen; + d += vlen; + + *curve_oid = NULL; + *curve_oid_len = 0; + + if (d < algid_end) { + switch (*d) { + + case ASN1_OBJECT_IDENTIFIER: + if ((err = hal_asn1_decode_header(ASN1_OBJECT_IDENTIFIER, d, algid_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + if (vlen > algid_end - d) + return HAL_ERROR_ASN1_PARSE_FAILED; + *curve_oid = d; + *curve_oid_len = vlen; + d += vlen; + break; + + case ASN1_NULL: + if ((err = hal_asn1_decode_header(ASN1_NULL, d, algid_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + if (vlen == 0) + break; + + default: + return HAL_ERROR_ASN1_PARSE_FAILED; + } + } + + if (d != algid_end) + return HAL_ERROR_ASN1_PARSE_FAILED; + + if ((err = hal_asn1_decode_header(ASN1_OCTET_STRING, d, der_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + if (vlen >= algid_end - d) + return HAL_ERROR_ASN1_PARSE_FAILED; + *privkey = d; + *privkey_len = vlen; + d += vlen; + + if (d != der_end) + return HAL_ERROR_ASN1_PARSE_FAILED; + + return HAL_OK; +} + +/* + * Decode a private key from a PKCS #8 EncryptedPrivateKeyInfo (RFC 5208). + */ + +hal_error_t hal_asn1_decode_pkcs8_encryptedprivatekeyinfo(const uint8_t **alg_oid, size_t *alg_oid_len, + const uint8_t **data, size_t *data_len, + const uint8_t *const der, const size_t der_len) +{ + if (alg_oid == NULL || alg_oid_len == NULL || data == NULL || data_len == NULL || der == NULL) + return HAL_ERROR_BAD_ARGUMENTS; + + const uint8_t * const der_end = der + der_len; + const uint8_t *d = der; + + size_t hlen, vlen; + hal_error_t err; + + if ((err = hal_asn1_decode_header(ASN1_SEQUENCE, d, der_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + + if (hlen + vlen != der_len) + return HAL_ERROR_ASN1_PARSE_FAILED; + + if ((err = hal_asn1_decode_header(ASN1_SEQUENCE, d, der_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + + const uint8_t * const algid_end = d + vlen; + + if ((err = hal_asn1_decode_header(ASN1_OBJECT_IDENTIFIER, d, algid_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + if (vlen > algid_end - d) + return HAL_ERROR_ASN1_PARSE_FAILED; + *alg_oid = d; + *alg_oid_len = vlen; + d += vlen; + + if (d != algid_end) + return HAL_ERROR_ASN1_PARSE_FAILED; + + if ((err = hal_asn1_decode_header(ASN1_OCTET_STRING, d, der_end - d, &hlen, &vlen)) != HAL_OK) + return err; + d += hlen; + if (vlen >= algid_end - d) + return HAL_ERROR_ASN1_PARSE_FAILED; + *data = d; + *data_len = vlen; + d += vlen; + + if (d != der_end) + return HAL_ERROR_ASN1_PARSE_FAILED; + + return HAL_OK; +} + +/* * Local variables: * indent-tabs-mode: nil * End: diff --git a/asn1_internal.h b/asn1_internal.h index 0b08b84..01ffc22 100644 --- a/asn1_internal.h +++ b/asn1_internal.h @@ -113,6 +113,24 @@ extern hal_error_t hal_asn1_decode_spki(const uint8_t **alg_oid, size_t *alg_o const uint8_t **pubkey, size_t *pubkey_len, const uint8_t *const der, const size_t der_len); +extern hal_error_t hal_asn1_encode_pkcs8_privatekeyinfo(const uint8_t * const alg_oid, const size_t alg_oid_len, + const uint8_t * const curve_oid, const size_t curve_oid_len, + const uint8_t * const privkey, const size_t privkey_len, + uint8_t *der, size_t *der_len, const size_t der_max); + +extern hal_error_t hal_asn1_decode_pkcs8_privatekeyinfo(const uint8_t **alg_oid, size_t *alg_oid_len, + const uint8_t **curve_oid, size_t *curve_oid_len, + const uint8_t **privkey, size_t *privkey_len, + const uint8_t *const der, const size_t der_len); + +extern hal_error_t hal_asn1_encode_pkcs8_encryptedprivatekeyinfo(const uint8_t * const alg_oid, const size_t alg_oid_len, + const uint8_t * const data, const size_t data_len, + uint8_t *der, size_t *der_len, const size_t der_max); + +extern hal_error_t hal_asn1_decode_pkcs8_encryptedprivatekeyinfo(const uint8_t **alg_oid, size_t *alg_oid_len, + const uint8_t **data, size_t *data_len, + const uint8_t *const der, const size_t der_len); + #endif /* _HAL_ASN1_INTERNAL_H_ */ /* |