psa: Simplify RSA public key format

Remove pkcs-1 and rsaEncryption front matter from RSA public keys. Move
code that was shared between RSA and other key types (like EC keys) to
be used only with non-RSA keys.
This commit is contained in:
Jaeden Amero
2019-01-10 10:23:21 +00:00
committed by Jaeden Amero
parent d3a0c2c779
commit 25384a236e
6 changed files with 104 additions and 90 deletions

View File

@@ -474,8 +474,17 @@ psa_status_t psa_export_key(psa_key_handle_t handle,
* minimize the risk that an invalid input is accidentally interpreted
* according to a different format.
*
* The format is the DER representation defined by RFC 5280 as
* `SubjectPublicKeyInfo`, with the `subjectPublicKey` format
* For standard key types, the output format is as follows:
* - For RSA public keys (#PSA_KEY_TYPE_RSA_PUBLIC_KEY), the DER encoding of
* the representation defined by RFC 3279 §2.3.1 as `RSAPublicKey`.
* ```
* RSAPublicKey ::= SEQUENCE {
* modulus INTEGER, -- n
* publicExponent INTEGER } -- e
* ```
*
* For other public key types, the format is the DER representation defined by
* RFC 5280 as `SubjectPublicKeyInfo`, with the `subjectPublicKey` format
* specified below.
* ```
* SubjectPublicKeyInfo ::= SEQUENCE {
@@ -485,21 +494,6 @@ psa_status_t psa_export_key(psa_key_handle_t handle,
* algorithm OBJECT IDENTIFIER,
* parameters ANY DEFINED BY algorithm OPTIONAL }
* ```
*
* - For RSA public keys (#PSA_KEY_TYPE_RSA_PUBLIC_KEY),
* the `subjectPublicKey` format is defined by RFC 3279 §2.3.1 as
* `RSAPublicKey`,
* with the OID `rsaEncryption`,
* and with the parameters `NULL`.
* ```
* pkcs-1 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840)
* rsadsi(113549) pkcs(1) 1 }
* rsaEncryption OBJECT IDENTIFIER ::= { pkcs-1 1 }
*
* RSAPublicKey ::= SEQUENCE {
* modulus INTEGER, -- n
* publicExponent INTEGER } -- e
* ```
* - For DSA public keys (#PSA_KEY_TYPE_DSA_PUBLIC_KEY),
* the `subjectPublicKey` format is defined by RFC 3279 §2.3.2 as
* `DSAPublicKey`,

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@@ -417,25 +417,16 @@
/* Maximum size of the export encoding of an RSA public key.
* Assumes that the public exponent is less than 2^32.
*
* SubjectPublicKeyInfo ::= SEQUENCE {
* algorithm AlgorithmIdentifier,
* subjectPublicKey BIT STRING } -- contains RSAPublicKey
* AlgorithmIdentifier ::= SEQUENCE {
* algorithm OBJECT IDENTIFIER,
* parameters NULL }
* RSAPublicKey ::= SEQUENCE {
* modulus INTEGER, -- n
* publicExponent INTEGER } -- e
*
* - 3 * 4 bytes of SEQUENCE overhead;
* - 1 + 1 + 9 bytes of algorithm (RSA OID);
* - 2 bytes of NULL;
* - 4 bytes of BIT STRING overhead;
* - 4 bytes of SEQUENCE overhead;
* - n : INTEGER;
* - 7 bytes for the public exponent.
*/
#define PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) \
(PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) + 36)
(PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) + 11)
/* Maximum size of the export encoding of an RSA key pair.
* Assumes thatthe public exponent is less than 2^32 and that the size