pkcs5v2: add support for additional hmacSHA algorithms

Currently only SHA1 is supported as PRF algorithm for PBKDF2
(PKCS#5 v2.0).
This means that keys encrypted and authenticated using
another algorithm of the SHA family cannot be decrypted.

This deficiency has become particularly incumbent now that
PKIs created with OpenSSL1.1 are encrypting keys using
hmacSHA256 by default (OpenSSL1.0 used PKCS#5 v1.0 by default
and even if v2 was forced, it would still use hmacSHA1).

Enable support for all the digest algorithms of the SHA
family for PKCS#5 v2.0.

Signed-off-by: Antonio Quartulli <antonio@openvpn.net>

ChangeLog

@@ -1,5 +1,12 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
+= mbed TLS x.x.x branch released xxxx-xx-xx
+
+Features
+   * Extend PKCS#8 interface by introducing support for the entire SHA
+     algorithms family when encrypting private keys using PKCS#5 v2.0.
+     Submitted by Antonio Quartulli, OpenVPN Inc.
+
 = mbed TLS 2.7.0 branch released 2018-02-03
 
 Security

include/mbedtls/oid.h

@@ -228,6 +228,14 @@
 
 #define MBEDTLS_OID_HMAC_SHA1                   MBEDTLS_OID_RSA_COMPANY "\x02\x07" /**< id-hmacWithSHA1 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 7 } */
 
+#define MBEDTLS_OID_HMAC_SHA224                 MBEDTLS_OID_RSA_COMPANY "\x02\x08" /**< id-hmacWithSHA224 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 8 } */
+
+#define MBEDTLS_OID_HMAC_SHA256                 MBEDTLS_OID_RSA_COMPANY "\x02\x09" /**< id-hmacWithSHA256 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 9 } */
+
+#define MBEDTLS_OID_HMAC_SHA384                 MBEDTLS_OID_RSA_COMPANY "\x02\x0A" /**< id-hmacWithSHA384 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 10 } */
+
+#define MBEDTLS_OID_HMAC_SHA512                 MBEDTLS_OID_RSA_COMPANY "\x02\x0B" /**< id-hmacWithSHA512 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 11 } */
+
 /*
  * Encryption algorithms
  */
@@ -514,6 +522,16 @@ int mbedtls_oid_get_oid_by_sig_alg( mbedtls_pk_type_t pk_alg, mbedtls_md_type_t
  * \return         0 if successful, or MBEDTLS_ERR_OID_NOT_FOUND
  */
 int mbedtls_oid_get_md_alg( const mbedtls_asn1_buf *oid, mbedtls_md_type_t *md_alg );
+
+/**
+ * \brief          Translate hmac algorithm OID into md_type
+ *
+ * \param oid      OID to use
+ * \param md_hmac  place to store message hmac algorithm
+ *
+ * \return         0 if successful, or MBEDTLS_ERR_OID_NOT_FOUND
+ */
+int mbedtls_oid_get_md_hmac( const mbedtls_asn1_buf *oid, mbedtls_md_type_t *md_hmac );
 #endif /* MBEDTLS_MD_C */
 
 /**

library/oid.c

@@ -625,6 +625,51 @@ static const oid_md_alg_t oid_md_alg[] =
 FN_OID_TYPED_FROM_ASN1(oid_md_alg_t, md_alg, oid_md_alg)
 FN_OID_GET_ATTR1(mbedtls_oid_get_md_alg, oid_md_alg_t, md_alg, mbedtls_md_type_t, md_alg)
 FN_OID_GET_OID_BY_ATTR1(mbedtls_oid_get_oid_by_md, oid_md_alg_t, oid_md_alg, mbedtls_md_type_t, md_alg)
+
+/*
+ * For HMAC digestAlgorithm
+ */
+typedef struct {
+    mbedtls_oid_descriptor_t    descriptor;
+    mbedtls_md_type_t           md_hmac;
+} oid_md_hmac_t;
+
+static const oid_md_hmac_t oid_md_hmac[] =
+{
+#if defined(MBEDTLS_SHA1_C)
+    {
+        { ADD_LEN( MBEDTLS_OID_HMAC_SHA1 ),      "hmacSHA1",      "HMAC-SHA-1" },
+        MBEDTLS_MD_SHA1,
+    },
+#endif /* MBEDTLS_SHA1_C */
+#if defined(MBEDTLS_SHA256_C)
+    {
+        { ADD_LEN( MBEDTLS_OID_HMAC_SHA224 ),    "hmacSHA224",    "HMAC-SHA-224" },
+        MBEDTLS_MD_SHA224,
+    },
+    {
+        { ADD_LEN( MBEDTLS_OID_HMAC_SHA256 ),    "hmacSHA256",    "HMAC-SHA-256" },
+        MBEDTLS_MD_SHA256,
+    },
+#endif /* MBEDTLS_SHA256_C */
+#if defined(MBEDTLS_SHA512_C)
+    {
+        { ADD_LEN( MBEDTLS_OID_HMAC_SHA384 ),    "hmacSHA384",    "HMAC-SHA-384" },
+        MBEDTLS_MD_SHA384,
+    },
+    {
+        { ADD_LEN( MBEDTLS_OID_HMAC_SHA512 ),    "hmacSHA512",    "HMAC-SHA-512" },
+        MBEDTLS_MD_SHA512,
+    },
+#endif /* MBEDTLS_SHA512_C */
+    {
+        { NULL, 0, NULL, NULL },
+        MBEDTLS_MD_NONE,
+    },
+};
+
+FN_OID_TYPED_FROM_ASN1(oid_md_hmac_t, md_hmac, oid_md_hmac)
+FN_OID_GET_ATTR1(mbedtls_oid_get_md_hmac, oid_md_hmac_t, md_hmac, mbedtls_md_type_t, md_hmac)
 #endif /* MBEDTLS_MD_C */
 
 #if defined(MBEDTLS_PKCS12_C)

library/pkcs5.c

@@ -96,11 +96,9 @@ static int pkcs5_parse_pbkdf2_params( const mbedtls_asn1_buf *params,
     if( ( ret = mbedtls_asn1_get_alg_null( &p, end, &prf_alg_oid ) ) != 0 )
         return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret );
 
-    if( MBEDTLS_OID_CMP( MBEDTLS_OID_HMAC_SHA1, &prf_alg_oid ) != 0 )
+    if( mbedtls_oid_get_md_hmac( &prf_alg_oid, md_type ) != 0 )
         return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
 
-    *md_type = MBEDTLS_MD_SHA1;
-
     if( p != end )
         return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT +
                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );

tests/suites/test_suite_pkcs5.data

@@ -82,9 +82,9 @@ PBES2 Decrypt (bad, PBKDF2 params explicit prf_alg overlong)
 depends_on:MBEDTLS_SHA1_C:MBEDTLS_DES_C
 mbedtls_pkcs5_pbes2:MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE:"301D06092A864886F70D01050C301004082ED7F24A1D516DD7020208003001":"":"":MBEDTLS_ERR_PKCS5_INVALID_FORMAT + MBEDTLS_ERR_ASN1_OUT_OF_DATA:""
 
-PBES2 Decrypt (bad, PBKDF2 params explicit prf_alg != HMAC-SHA1)
+PBES2 Decrypt (bad, PBKDF2 params explicit prf_alg != HMAC-SHA*)
 depends_on:MBEDTLS_SHA1_C:MBEDTLS_DES_C
-mbedtls_pkcs5_pbes2:MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE:"302706092A864886F70D01050C301A04082ED7F24A1D516DD702020800300A06082A864886F70D0208":"":"":MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE:""
+mbedtls_pkcs5_pbes2:MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE:"302706092A864886F70D01050C301A04082ED7F24A1D516DD702020800300A06082A864886F70D0206":"":"":MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE:""
 
 PBES2 Decrypt (bad, PBKDF2 params extra data)
 depends_on:MBEDTLS_SHA1_C:MBEDTLS_DES_C