Revert "Merged RSA-PSS support in Certificate, CSR and CRL"

This reverts commit ab50d8d30c22f38e3e2d2373219cfbeb1940082e, reversing
changes made to e31b1d992ad0a3874646c73a44f3eb750d13e900.
diff --git a/library/oid.c b/library/oid.c
index 1078608..f943c6d 100644
--- a/library/oid.c
+++ b/library/oid.c
@@ -328,10 +328,6 @@
         POLARSSL_MD_SHA512,   POLARSSL_PK_ECDSA,
     },
     {
-        { ADD_LEN( OID_RSASSA_PSS ),        "RSASSA-PSS",           "RSASSA-PSS" },
-        POLARSSL_MD_NONE,     POLARSSL_PK_RSASSA_PSS,
-    },
-    {
         { NULL, 0, NULL, NULL },
         0, 0,
     },
diff --git a/library/x509.c b/library/x509.c
index 17e8b4d..e042347 100644
--- a/library/x509.c
+++ b/library/x509.c
@@ -120,215 +120,6 @@
 }
 
 /*
- * Parse an algorithm identifier with (optional) paramaters
- */
-int x509_get_alg( unsigned char **p, const unsigned char *end,
-                  x509_buf *alg, x509_buf *params )
-{
-    int ret;
-
-    if( ( ret = asn1_get_alg( p, end, alg, params ) ) != 0 )
-        return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-    return( 0 );
-}
-
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-/*
- * HashAlgorithm ::= AlgorithmIdentifier
- *
- * AlgorithmIdentifier  ::=  SEQUENCE  {
- *      algorithm               OBJECT IDENTIFIER,
- *      parameters              ANY DEFINED BY algorithm OPTIONAL  }
- *
- * For HashAlgorithm, parameters MUST be NULL or absent.
- */
-static int x509_get_hash_alg( const x509_buf *alg, md_type_t *md_alg )
-{
-    int ret;
-    unsigned char *p;
-    const unsigned char *end;
-    x509_buf md_oid;
-    size_t len;
-
-    /* Make sure we got a SEQUENCE and setup bounds */
-    if( alg->tag != ( ASN1_CONSTRUCTED | ASN1_SEQUENCE ) )
-        return( POLARSSL_ERR_X509_INVALID_ALG +
-                POLARSSL_ERR_ASN1_UNEXPECTED_TAG );
-
-    p = (unsigned char *) alg->p;
-    end = p + alg->len;
-
-    if( p >= end )
-        return( POLARSSL_ERR_X509_INVALID_ALG +
-                POLARSSL_ERR_ASN1_OUT_OF_DATA );
-
-    /* Parse md_oid */
-    md_oid.tag = *p;
-
-    if( ( ret = asn1_get_tag( &p, end, &md_oid.len, ASN1_OID ) ) != 0 )
-        return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-    md_oid.p = p;
-    p += md_oid.len;
-
-    /* Get md_alg from md_oid */
-    if( ( ret = oid_get_md_alg( &md_oid, md_alg ) ) != 0 )
-        return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-    /* Make sure params is absent of NULL */
-    if( p == end )
-        return( 0 );
-
-    if( ( ret = asn1_get_tag( &p, end, &len, ASN1_NULL ) ) != 0 || len != 0 )
-        return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-    if( p != end )
-        return( POLARSSL_ERR_X509_INVALID_ALG +
-                POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
-
-    return( 0 );
-}
-
-/*
- *    RSASSA-PSS-params  ::=  SEQUENCE  {
- *       hashAlgorithm     [0] HashAlgorithm DEFAULT sha1Identifier,
- *       maskGenAlgorithm  [1] MaskGenAlgorithm DEFAULT mgf1SHA1Identifier,
- *       saltLength        [2] INTEGER DEFAULT 20,
- *       trailerField      [3] INTEGER DEFAULT 1  }
- *    -- Note that the tags in this Sequence are explicit.
- */
-int x509_get_rsassa_pss_params( const x509_buf *params,
-                                md_type_t *md_alg, md_type_t *mgf_md,
-                                int *salt_len, int *trailer_field )
-{
-    int ret;
-    unsigned char *p;
-    const unsigned char *end, *end2;
-    size_t len;
-    x509_buf alg_id, alg_params;
-
-    /* First set everything to defaults */
-    *md_alg = POLARSSL_MD_SHA1;
-    *mgf_md = POLARSSL_MD_SHA1;
-    *salt_len = 20;
-    *trailer_field = 1;
-
-    /* Make sure params is a SEQUENCE and setup bounds */
-    if( params->tag != ( ASN1_CONSTRUCTED | ASN1_SEQUENCE ) )
-        return( POLARSSL_ERR_X509_INVALID_ALG +
-                POLARSSL_ERR_ASN1_UNEXPECTED_TAG );
-
-    p = (unsigned char *) params->p;
-    end = p + params->len;
-
-    if( p == end )
-        return( 0 );
-
-    /*
-     * HashAlgorithm
-     */
-    if( ( ret = asn1_get_tag( &p, end, &len,
-                    ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 0 ) ) == 0 )
-    {
-        end2 = p + len;
-
-        /* HashAlgorithm ::= AlgorithmIdentifier (without parameters) */
-        if( ( ret = x509_get_alg_null( &p, end2, &alg_id ) ) != 0 )
-            return( ret );
-
-        if( ( ret = oid_get_md_alg( &alg_id, md_alg ) ) != 0 )
-            return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-        if( p != end2 )
-            return( POLARSSL_ERR_X509_INVALID_ALG +
-                    POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
-    }
-    else if( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
-        return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-    if( p == end )
-        return( 0 );
-
-    /*
-     * MaskGenAlgorithm
-     */
-    if( ( ret = asn1_get_tag( &p, end, &len,
-                    ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 1 ) ) == 0 )
-    {
-        end2 = p + len;
-
-        /* MaskGenAlgorithm ::= AlgorithmIdentifier (params = HashAlgorithm) */
-        if( ( ret = x509_get_alg( &p, end2, &alg_id, &alg_params ) ) != 0 )
-            return( ret );
-
-        /* Only MFG1 is recognised for now */
-        if( ! OID_CMP( OID_MGF1, &alg_id ) )
-            return( POLARSSL_ERR_X509_FEATURE_UNAVAILABLE +
-                    POLARSSL_ERR_OID_NOT_FOUND );
-
-        /* Parse HashAlgorithm */
-        if( ( ret = x509_get_hash_alg( &alg_params, mgf_md ) ) != 0 )
-            return( ret );
-
-        if( p != end2 )
-            return( POLARSSL_ERR_X509_INVALID_ALG +
-                    POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
-    }
-    else if( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
-        return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-    if( p == end )
-        return( 0 );
-
-    /*
-     * salt_len
-     */
-    if( ( ret = asn1_get_tag( &p, end, &len,
-                    ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 2 ) ) == 0 )
-    {
-        end2 = p + len;
-
-        if( ( ret = asn1_get_int( &p, end2, salt_len ) ) != 0 )
-            return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-        if( p != end2 )
-            return( POLARSSL_ERR_X509_INVALID_ALG +
-                    POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
-    }
-    else if( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
-        return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-    if( p == end )
-        return( 0 );
-
-    /*
-     * trailer_field
-     */
-    if( ( ret = asn1_get_tag( &p, end, &len,
-                    ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 3 ) ) == 0 )
-    {
-        end2 = p + len;
-
-        if( ( ret = asn1_get_int( &p, end2, trailer_field ) ) != 0 )
-            return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-        if( p != end2 )
-            return( POLARSSL_ERR_X509_INVALID_ALG +
-                    POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
-    }
-    else if( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
-        return( POLARSSL_ERR_X509_INVALID_ALG + ret );
-
-    if( p != end )
-        return( POLARSSL_ERR_X509_INVALID_ALG +
-                POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
-
-    return( 0 );
-}
-#endif /* POLARSSL_RSASSA_PSS_CERTIFICATES */
-
-/*
  *  AttributeTypeAndValue ::= SEQUENCE {
  *    type     AttributeType,
  *    value    AttributeValue }
@@ -543,39 +334,14 @@
     return( 0 );
 }
 
-/*
- * Get signature algorithm from alg OID and optional parameters
- */
-int x509_get_sig_alg( const x509_buf *sig_oid, const x509_buf *sig_params,
-                      md_type_t *md_alg, pk_type_t *pk_alg )
+int x509_get_sig_alg( const x509_buf *sig_oid, md_type_t *md_alg,
+                      pk_type_t *pk_alg )
 {
-    int ret;
+    int ret = oid_get_sig_alg( sig_oid, md_alg, pk_alg );
 
-    if( ( ret = oid_get_sig_alg( sig_oid, md_alg, pk_alg ) ) != 0 )
+    if( ret != 0 )
         return( POLARSSL_ERR_X509_UNKNOWN_SIG_ALG + ret );
 
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-    if( *pk_alg == POLARSSL_PK_RSASSA_PSS )
-    {
-        int salt_len, trailer_field;
-        md_type_t mgf_md;
-
-        /* Make sure params are valid */
-        ret = x509_get_rsassa_pss_params( sig_params,
-                md_alg, &mgf_md, &salt_len, &trailer_field );
-        if( ret != 0 )
-            return( ret );
-
-    }
-    else
-#endif
-    {
-        /* Make sure parameters are absent or NULL */
-        if( ( sig_params->tag != ASN1_NULL && sig_params->tag != 0 ) ||
-              sig_params->len != 0 )
-        return( POLARSSL_ERR_X509_INVALID_ALG );
-    }
-
     return( 0 );
 }
 
@@ -812,52 +578,6 @@
 }
 
 /*
- * Helper for writing signature alrogithms
- */
-int x509_sig_alg_gets( char *buf, size_t size, const x509_buf *sig_oid,
-                       pk_type_t pk_alg, const x509_buf *sig_params )
-{
-    int ret;
-    char *p = buf;
-    size_t n = size;
-    const char *desc = NULL;
-
-    ret = oid_get_sig_alg_desc( sig_oid, &desc );
-    if( ret != 0 )
-        ret = snprintf( p, n, "???"  );
-    else
-        ret = snprintf( p, n, "%s", desc );
-    SAFE_SNPRINTF();
-
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-    if( pk_alg == POLARSSL_PK_RSASSA_PSS )
-    {
-        md_type_t md_alg, mgf_md;
-        const md_info_t *md_info, *mgf_md_info;
-        int salt_len, trailer_field;
-
-        if( ( ret = x509_get_rsassa_pss_params( sig_params,
-                        &md_alg, &mgf_md, &salt_len, &trailer_field ) ) != 0 )
-            return( ret );
-
-        md_info = md_info_from_type( md_alg );
-        mgf_md_info = md_info_from_type( mgf_md );
-
-        ret = snprintf( p, n, " (%s, MGF1-%s, 0x%02X, %d)",
-                              md_info ? md_info->name : "???",
-                              mgf_md_info ? mgf_md_info->name : "???",
-                              salt_len, trailer_field );
-        SAFE_SNPRINTF();
-    }
-#else
-    ((void) pk_alg);
-    ((void) sig_params);
-#endif /* POLARSSL_RSASSA_PSS_CERTIFICATES */
-
-    return( (int) size - n );
-}
-
-/*
  * Helper for writing "RSA key size", "EC key size", etc
  */
 int x509_key_size_helper( char *buf, size_t size, const char *name )
diff --git a/library/x509_crl.c b/library/x509_crl.c
index 92ede6d..e3ebbff 100644
--- a/library/x509_crl.c
+++ b/library/x509_crl.c
@@ -250,15 +250,11 @@
     size_t len;
     unsigned char *p, *end;
     x509_crl *crl;
-    x509_buf sig_params;
-
 #if defined(POLARSSL_PEM_PARSE_C)
     size_t use_len;
     pem_context pem;
 #endif
 
-    memset( &sig_params, 0, sizeof( x509_buf ) );
-
     crl = chain;
 
     /*
@@ -377,7 +373,7 @@
      * signature            AlgorithmIdentifier
      */
     if( ( ret = x509_crl_get_version( &p, end, &crl->version ) ) != 0 ||
-        ( ret = x509_get_alg( &p, end, &crl->sig_oid1, &sig_params ) ) != 0 )
+        ( ret = x509_get_alg_null( &p, end, &crl->sig_oid1   ) ) != 0 )
     {
         x509_crl_free( crl );
         return( ret );
@@ -391,17 +387,13 @@
         return( POLARSSL_ERR_X509_UNKNOWN_VERSION );
     }
 
-    if( ( ret = x509_get_sig_alg( &crl->sig_oid1, &sig_params,
-                                  &crl->sig_md, &crl->sig_pk ) ) != 0 )
+    if( ( ret = x509_get_sig_alg( &crl->sig_oid1, &crl->sig_md,
+                                  &crl->sig_pk ) ) != 0 )
     {
         x509_crl_free( crl );
         return( POLARSSL_ERR_X509_UNKNOWN_SIG_ALG );
     }
 
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-    memcpy( &crl->sig_params, &sig_params, sizeof( x509_buf ) );
-#endif
-
     /*
      * issuer               Name
      */
@@ -486,20 +478,14 @@
      *  signatureAlgorithm   AlgorithmIdentifier,
      *  signatureValue       BIT STRING
      */
-    if( ( ret = x509_get_alg( &p, end, &crl->sig_oid2, &sig_params ) ) != 0 )
+    if( ( ret = x509_get_alg_null( &p, end, &crl->sig_oid2 ) ) != 0 )
     {
         x509_crl_free( crl );
         return( ret );
     }
 
     if( crl->sig_oid1.len != crl->sig_oid2.len ||
-        memcmp( crl->sig_oid1.p, crl->sig_oid2.p, crl->sig_oid1.len ) != 0
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-        ||
-        crl->sig_params.len != sig_params.len ||
-        memcmp( crl->sig_params.p, sig_params.p, sig_params.len ) != 0
-#endif
-        )
+        memcmp( crl->sig_oid1.p, crl->sig_oid2.p, crl->sig_oid1.len ) != 0 )
     {
         x509_crl_free( crl );
         return( POLARSSL_ERR_X509_SIG_MISMATCH );
@@ -625,12 +611,8 @@
     int ret;
     size_t n;
     char *p;
+    const char *desc;
     const x509_crl_entry *entry;
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-    const x509_buf *sig_params = &crl->sig_params;
-#else
-    const x509_buf *sig_params = NULL;
-#endif
 
     p = buf;
     n = size;
@@ -686,7 +668,11 @@
     ret = snprintf( p, n, "\n%ssigned using  : ", prefix );
     SAFE_SNPRINTF();
 
-    ret = x509_sig_alg_gets( p, n, &crl->sig_oid1, crl->sig_pk, sig_params );
+    ret = oid_get_sig_alg_desc( &crl->sig_oid1, &desc );
+    if( ret != 0 )
+        ret = snprintf( p, n, "???"  );
+    else
+        ret = snprintf( p, n, "%s", desc );
     SAFE_SNPRINTF();
 
     ret = snprintf( p, n, "\n" );
diff --git a/library/x509_crt.c b/library/x509_crt.c
index 4c79a7a..d18e117 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -529,9 +529,6 @@
     int ret;
     size_t len;
     unsigned char *p, *end, *crt_end;
-    x509_buf sig_params;
-
-    memset( &sig_params, 0, sizeof( x509_buf ) );
 
     /*
      * Check for valid input
@@ -595,8 +592,7 @@
      */
     if( ( ret = x509_get_version(  &p, end, &crt->version  ) ) != 0 ||
         ( ret = x509_get_serial(   &p, end, &crt->serial   ) ) != 0 ||
-        ( ret = x509_get_alg(      &p, end, &crt->sig_oid1,
-                                            &sig_params ) ) != 0 )
+        ( ret = x509_get_alg_null( &p, end, &crt->sig_oid1 ) ) != 0 )
     {
         x509_crt_free( crt );
         return( ret );
@@ -610,17 +606,13 @@
         return( POLARSSL_ERR_X509_UNKNOWN_VERSION );
     }
 
-    if( ( ret = x509_get_sig_alg( &crt->sig_oid1, &sig_params,
-                                  &crt->sig_md, &crt->sig_pk ) ) != 0 )
+    if( ( ret = x509_get_sig_alg( &crt->sig_oid1, &crt->sig_md,
+                                  &crt->sig_pk ) ) != 0 )
     {
         x509_crt_free( crt );
         return( ret );
     }
 
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-    memcpy( &crt->sig_params, &sig_params, sizeof( x509_buf ) );
-#endif
-
     /*
      * issuer               Name
      */
@@ -741,20 +733,14 @@
      *  signatureAlgorithm   AlgorithmIdentifier,
      *  signatureValue       BIT STRING
      */
-    if( ( ret = x509_get_alg( &p, end, &crt->sig_oid2, &sig_params ) ) != 0 )
+    if( ( ret = x509_get_alg_null( &p, end, &crt->sig_oid2 ) ) != 0 )
     {
         x509_crt_free( crt );
         return( ret );
     }
 
     if( crt->sig_oid1.len != crt->sig_oid2.len ||
-        memcmp( crt->sig_oid1.p, crt->sig_oid2.p, crt->sig_oid1.len ) != 0
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-        ||
-        crt->sig_params.len != sig_params.len ||
-        memcmp( crt->sig_params.p, sig_params.p, sig_params.len ) != 0
-#endif
-        )
+        memcmp( crt->sig_oid1.p, crt->sig_oid2.p, crt->sig_oid1.len ) != 0 )
     {
         x509_crt_free( crt );
         return( POLARSSL_ERR_X509_SIG_MISMATCH );
@@ -1124,12 +1110,8 @@
     int ret;
     size_t n;
     char *p;
+    const char *desc = NULL;
     char key_size_str[BEFORE_COLON];
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-    const x509_buf *sig_params = &crt->sig_params;
-#else
-    const x509_buf *sig_params = NULL;
-#endif
 
     p = buf;
     n = size;
@@ -1171,7 +1153,11 @@
     ret = snprintf( p, n, "\n%ssigned using  : ", prefix );
     SAFE_SNPRINTF();
 
-    ret = x509_sig_alg_gets( p, n, &crt->sig_oid1, crt->sig_pk, sig_params );
+    ret = oid_get_sig_alg_desc( &crt->sig_oid1, &desc );
+    if( ret != 0 )
+        ret = snprintf( p, n, "???"  );
+    else
+        ret = snprintf( p, n, "%s", desc );
     SAFE_SNPRINTF();
 
     if( ( ret = x509_key_size_helper( key_size_str, BEFORE_COLON,
diff --git a/library/x509_csr.c b/library/x509_csr.c
index bdadec3..4fb9ac2 100644
--- a/library/x509_csr.c
+++ b/library/x509_csr.c
@@ -89,7 +89,6 @@
     int ret;
     size_t len;
     unsigned char *p, *end;
-    x509_buf sig_params;
 #if defined(POLARSSL_PEM_PARSE_C)
     size_t use_len;
     pem_context pem;
@@ -244,23 +243,19 @@
      *  signatureAlgorithm   AlgorithmIdentifier,
      *  signature            BIT STRING
      */
-    if( ( ret = x509_get_alg( &p, end, &csr->sig_oid, &sig_params ) ) != 0 )
+    if( ( ret = x509_get_alg_null( &p, end, &csr->sig_oid ) ) != 0 )
     {
         x509_csr_free( csr );
         return( ret );
     }
 
-    if( ( ret = x509_get_sig_alg( &csr->sig_oid, &sig_params,
-                                  &csr->sig_md, &csr->sig_pk ) ) != 0 )
+    if( ( ret = x509_get_sig_alg( &csr->sig_oid, &csr->sig_md,
+                                  &csr->sig_pk ) ) != 0 )
     {
         x509_csr_free( csr );
         return( POLARSSL_ERR_X509_UNKNOWN_SIG_ALG );
     }
 
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-    memcpy( &csr->sig_params, &sig_params, sizeof( x509_buf ) );
-#endif
-
     if( ( ret = x509_get_sig( &p, end, &csr->sig ) ) != 0 )
     {
         x509_csr_free( csr );
@@ -362,12 +357,8 @@
     int ret;
     size_t n;
     char *p;
+    const char *desc;
     char key_size_str[BEFORE_COLON];
-#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
-    const x509_buf *sig_params = &csr->sig_params;
-#else
-    const x509_buf *sig_params = NULL;
-#endif
 
     p = buf;
     n = size;
@@ -384,7 +375,11 @@
     ret = snprintf( p, n, "\n%ssigned using  : ", prefix );
     SAFE_SNPRINTF();
 
-    ret = x509_sig_alg_gets( p, n, &csr->sig_oid, csr->sig_pk, sig_params );
+    ret = oid_get_sig_alg_desc( &csr->sig_oid, &desc );
+    if( ret != 0 )
+        ret = snprintf( p, n, "???"  );
+    else
+        ret = snprintf( p, n, "%s", desc );
     SAFE_SNPRINTF();
 
     if( ( ret = x509_key_size_helper( key_size_str, BEFORE_COLON,