Update RSA ASN.1 code to handle RSA-PSS.

From OpenSSL 1.1.1d.

ok tb@

4 files changed, 389 insertions, 302 deletions

diff --git a/src/lib/libcrypto/rsa/rsa.h b/src/lib/libcrypto/rsa/rsa.h
index 48d6d64bd1..86e5f8e20f 100644
--- a/src/lib/libcrypto/rsa/rsa.h
+++ b/src/lib/libcrypto/rsa/rsa.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: rsa.h,v 1.45 2019/10/31 13:56:29 jsing Exp $ */
+/* $OpenBSD: rsa.h,v 1.46 2019/11/01 03:45:13 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -615,6 +615,7 @@ void ERR_load_RSA_strings(void);
 #define RSA_R_DATA_TOO_LARGE_FOR_MODULUS                 132
 #define RSA_R_DATA_TOO_SMALL                             111
 #define RSA_R_DATA_TOO_SMALL_FOR_KEY_SIZE                122
+#define RSA_R_DIGEST_DOES_NOT_MATCH                      158
 #define RSA_R_DIGEST_NOT_ALLOWED                         145
 #define RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY                 112
 #define RSA_R_DMP1_NOT_CONGRUENT_TO_D                    124
diff --git a/src/lib/libcrypto/rsa/rsa_ameth.c b/src/lib/libcrypto/rsa/rsa_ameth.c
index f71cee8ec1..d23848d0d5 100644
--- a/src/lib/libcrypto/rsa/rsa_ameth.c
+++ b/src/lib/libcrypto/rsa/rsa_ameth.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: rsa_ameth.c,v 1.20 2019/10/31 13:56:29 jsing Exp $ */
+/* $OpenBSD: rsa_ameth.c,v 1.21 2019/11/01 03:45:13 jsing Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2006.
  */
@@ -66,23 +66,81 @@
 #include <openssl/rsa.h>
 #include <openssl/x509.h>
 
-
 #include "asn1_locl.h"
+#include "rsa_locl.h"
+
+static RSA_PSS_PARAMS *rsa_pss_decode(const X509_ALGOR *alg);
+
+/* Set any parameters associated with pkey */
+static int
+rsa_param_encode(const EVP_PKEY *pkey, ASN1_STRING **pstr, int *pstrtype)
+{
+        const RSA *rsa = pkey->pkey.rsa;
+
+        *pstr = NULL;
+
+        /* If RSA it's just NULL type */
+        if (pkey->ameth->pkey_id != EVP_PKEY_RSA_PSS) {
+                *pstrtype = V_ASN1_NULL;
+                return 1;
+        }
+
+        /* If no PSS parameters we omit parameters entirely */
+        if (rsa->pss == NULL) {
+                *pstrtype = V_ASN1_UNDEF;
+                return 1;
+        }
+
+        /* Encode PSS parameters */
+        if (ASN1_item_pack(rsa->pss, &RSA_PSS_PARAMS_it, pstr) == NULL)
+                return 0;
+
+        *pstrtype = V_ASN1_SEQUENCE;
+        return 1;
+}
+
+/* Decode any parameters and set them in RSA structure */
+static int
+rsa_param_decode(RSA *rsa, const X509_ALGOR *alg)
+{
+        const ASN1_OBJECT *algoid;
+        const void *algp;
+        int algptype;
+
+        X509_ALGOR_get0(&algoid, &algptype, &algp, alg);
+        if (OBJ_obj2nid(algoid) != EVP_PKEY_RSA_PSS)
+                return 1;
+        if (algptype == V_ASN1_UNDEF)
+                return 1;
+        if (algptype != V_ASN1_SEQUENCE) {
+                RSAerror(RSA_R_INVALID_PSS_PARAMETERS);
+                return 0;
+        }
+        rsa->pss = rsa_pss_decode(alg);
+        if (rsa->pss == NULL)
+                return 0;
+        return 1;
+}
 
 static int
 rsa_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
 {
         unsigned char *penc = NULL;
         int penclen;
+        ASN1_STRING *str;
+        int strtype;
 
+        if (!rsa_param_encode(pkey, &str, &strtype))
+                return 0;
         penclen = i2d_RSAPublicKey(pkey->pkey.rsa, &penc);
         if (penclen <= 0)
                 return 0;
-        if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_RSA),
-            V_ASN1_NULL, NULL, penc, penclen))
+        if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(pkey->ameth->pkey_id),
+            strtype, str, penc, penclen))
                 return 1;
 
         free(penc);
+
         return 0;
 }
 
@@ -91,15 +149,23 @@ rsa_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
 {
         const unsigned char *p;
         int pklen;
+        X509_ALGOR *alg;
         RSA *rsa = NULL;
 
-        if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, NULL, pubkey))
+        if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &alg, pubkey))
                 return 0;
-        if (!(rsa = d2i_RSAPublicKey(NULL, &p, pklen))) {
+        if ((rsa = d2i_RSAPublicKey(NULL, &p, pklen)) == NULL) {
                 RSAerror(ERR_R_RSA_LIB);
                 return 0;
         }
-        EVP_PKEY_assign_RSA (pkey, rsa);
+        if (!rsa_param_decode(rsa, alg)) {
+                RSA_free(rsa);
+                return 0;
+        }
+        if (!EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, rsa)) {
+                RSA_free(rsa);
+                return 0;
+        }
         return 1;
 }
 
@@ -109,6 +175,7 @@ rsa_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
         if (BN_cmp(b->pkey.rsa->n, a->pkey.rsa->n) != 0 ||
             BN_cmp(b->pkey.rsa->e, a->pkey.rsa->e) != 0)
                 return 0;
+
         return 1;
 }
 
@@ -117,11 +184,11 @@ old_rsa_priv_decode(EVP_PKEY *pkey, const unsigned char **pder, int derlen)
 {
         RSA *rsa;
 
-        if (!(rsa = d2i_RSAPrivateKey (NULL, pder, derlen))) {
+        if ((rsa = d2i_RSAPrivateKey(NULL, pder, derlen)) == NULL) {
                 RSAerror(ERR_R_RSA_LIB);
                 return 0;
         }
-        EVP_PKEY_assign_RSA(pkey, rsa);
+        EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, rsa);
         return 1;
 }
 
@@ -136,17 +203,23 @@ rsa_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
 {
         unsigned char *rk = NULL;
         int rklen;
+        ASN1_STRING *str;
+        int strtype;
 
-        rklen = i2d_RSAPrivateKey(pkey->pkey.rsa, &rk);
+        if (!rsa_param_encode(pkey, &str, &strtype))
+                return 0;
 
+        rklen = i2d_RSAPrivateKey(pkey->pkey.rsa, &rk);
         if (rklen <= 0) {
                 RSAerror(ERR_R_MALLOC_FAILURE);
+                ASN1_STRING_free(str);
                 return 0;
         }
 
-        if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_rsaEncryption), 0,
-            V_ASN1_NULL, NULL, rk, rklen)) {
+        if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(pkey->ameth->pkey_id), 0,
+            strtype, str, rk, rklen)) {
                 RSAerror(ERR_R_MALLOC_FAILURE);
+                ASN1_STRING_free(str);
                 return 0;
         }
 
@@ -157,11 +230,24 @@ static int
 rsa_priv_decode(EVP_PKEY *pkey, const PKCS8_PRIV_KEY_INFO *p8)
 {
         const unsigned char *p;
+        RSA *rsa;
         int pklen;
+        const X509_ALGOR *alg;
 
-        if (!PKCS8_pkey_get0(NULL, &p, &pklen, NULL, p8))
+        if (!PKCS8_pkey_get0(NULL, &p, &pklen, &alg, p8))
+                return 0;
+        rsa = d2i_RSAPrivateKey(NULL, &p, pklen);
+        if (rsa == NULL) {
+                RSAerror(ERR_R_RSA_LIB);
+                return 0;
+        }
+        if (!rsa_param_decode(rsa, alg)) {
+                RSA_free(rsa);
                 return 0;
-        return old_rsa_priv_decode(pkey, &p, pklen);
+        }
+        EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, rsa);
+
+        return 1;
 }
 
 static int
@@ -182,123 +268,29 @@ int_rsa_free(EVP_PKEY *pkey)
         RSA_free(pkey->pkey.rsa);
 }
 
-static void
-update_buflen(const BIGNUM *b, size_t *pbuflen)
-{
-        size_t i;
-
-        if (!b)
-                return;
-        if (*pbuflen < (i = (size_t)BN_num_bytes(b)))
-                *pbuflen = i;
-}
-
-static int
-do_rsa_print(BIO *bp, const RSA *x, int off, int priv)
-{
-        char *str;
-        const char *s;
-        unsigned char *m = NULL;
-        int ret = 0, mod_len = 0;
-        size_t buf_len = 0;
-
-        update_buflen(x->n, &buf_len);
-        update_buflen(x->e, &buf_len);
-
-        if (priv) {
-                update_buflen(x->d, &buf_len);
-                update_buflen(x->p, &buf_len);
-                update_buflen(x->q, &buf_len);
-                update_buflen(x->dmp1, &buf_len);
-                update_buflen(x->dmq1, &buf_len);
-                update_buflen(x->iqmp, &buf_len);
-        }
-
-        m = malloc(buf_len + 10);
-        if (m == NULL) {
-                RSAerror(ERR_R_MALLOC_FAILURE);
-                goto err;
-        }
-
-        if (x->n != NULL)
-                mod_len = BN_num_bits(x->n);
-
-        if (!BIO_indent(bp, off, 128))
-                goto err;
-
-        if (priv && x->d) {
-                if (BIO_printf(bp, "Private-Key: (%d bit)\n", mod_len) <= 0)
-                        goto err;
-                str = "modulus:";
-                s = "publicExponent:";
-        } else {
-                if (BIO_printf(bp, "Public-Key: (%d bit)\n", mod_len) <= 0)
-                        goto err;
-                str = "Modulus:";
-                s= "Exponent:";
-        }
-        if (!ASN1_bn_print(bp, str, x->n, m, off))
-                goto err;
-        if (!ASN1_bn_print(bp, s, x->e, m, off))
-                goto err;
-        if (priv) {
-                if (!ASN1_bn_print(bp, "privateExponent:", x->d,m, off))
-                        goto err;
-                if (!ASN1_bn_print(bp, "prime1:", x->p, m, off))
-                        goto err;
-                if (!ASN1_bn_print(bp, "prime2:", x->q, m, off))
-                        goto err;
-                if (!ASN1_bn_print(bp, "exponent1:", x->dmp1, m, off))
-                        goto err;
-                if (!ASN1_bn_print(bp, "exponent2:", x->dmq1, m, off))
-                        goto err;
-                if (!ASN1_bn_print(bp, "coefficient:", x->iqmp, m, off))
-                        goto err;
-        }
-        ret = 1;
-err:
-        free(m);
-        return (ret);
-}
-
-static int
-rsa_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent, ASN1_PCTX *ctx)
+static X509_ALGOR *
+rsa_mgf1_decode(X509_ALGOR *alg)
 {
-        return do_rsa_print(bp, pkey->pkey.rsa, indent, 0);
-}
+        if (OBJ_obj2nid(alg->algorithm) != NID_mgf1)
+                return NULL;
 
-static int
-rsa_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent, ASN1_PCTX *ctx)
-{
-        return do_rsa_print(bp, pkey->pkey.rsa, indent, 1);
+        return ASN1_TYPE_unpack_sequence(&X509_ALGOR_it, alg->parameter);
 }
 
 static RSA_PSS_PARAMS *
-rsa_pss_decode(const X509_ALGOR *alg, X509_ALGOR **pmaskHash)
+rsa_pss_decode(const X509_ALGOR *alg)
 {
-        const unsigned char *p;
-        int plen;
         RSA_PSS_PARAMS *pss;
 
-        *pmaskHash = NULL;
-
-        if (!alg->parameter || alg->parameter->type != V_ASN1_SEQUENCE)
-                return NULL;
-
-        p = alg->parameter->value.sequence->data;
-        plen = alg->parameter->value.sequence->length;
-        pss = d2i_RSA_PSS_PARAMS(NULL, &p, plen);
-
-        if (!pss)
+        pss = ASN1_TYPE_unpack_sequence(&RSA_PSS_PARAMS_it, alg->parameter);
+        if (pss == NULL)
                 return NULL;
 
-        if (pss->maskGenAlgorithm) {
-                ASN1_TYPE *param = pss->maskGenAlgorithm->parameter;
-                if (OBJ_obj2nid(pss->maskGenAlgorithm->algorithm) == NID_mgf1 &&
-                    param && param->type == V_ASN1_SEQUENCE) {
-                        p = param->value.sequence->data;
-                        plen = param->value.sequence->length;
-                        *pmaskHash = d2i_X509_ALGOR(NULL, &p, plen);
+        if (pss->maskGenAlgorithm != NULL) {
+                pss->maskHash = rsa_mgf1_decode(pss->maskGenAlgorithm);
+                if (pss->maskHash == NULL) {
+                        RSA_PSS_PARAMS_free(pss);
+                        return NULL;
                 }
         }
 
@@ -306,18 +298,31 @@ rsa_pss_decode(const X509_ALGOR *alg, X509_ALGOR **pmaskHash)
 }
 
 static int
-rsa_pss_param_print(BIO *bp, RSA_PSS_PARAMS *pss, X509_ALGOR *maskHash,
-    int indent)
+rsa_pss_param_print(BIO *bp, int pss_key, RSA_PSS_PARAMS *pss, int indent)
 {
         int rv = 0;
+        X509_ALGOR *maskHash = NULL;
 
-        if (!pss) {
-                if (BIO_puts(bp, " (INVALID PSS PARAMETERS)\n") <= 0)
+        if (!BIO_indent(bp, indent, 128))
+                goto err;
+        if (pss_key) {
+                if (pss == NULL) {
+                        if (BIO_puts(bp, "No PSS parameter restrictions\n") <= 0)
+                                return 0;
+                        return 1;
+                } else {
+                        if (BIO_puts(bp, "PSS parameter restrictions:") <= 0)
+                                return 0;
+                }
+        } else if (pss == NULL) {
+                if (BIO_puts(bp,"(INVALID PSS PARAMETERS)\n") <= 0)
                         return 0;
                 return 1;
         }
         if (BIO_puts(bp, "\n") <= 0)
                 goto err;
+        if (pss_key)
+                indent += 2;
         if (!BIO_indent(bp, indent, 128))
                 goto err;
         if (BIO_puts(bp, "Hash Algorithm: ") <= 0)
@@ -326,8 +331,9 @@ rsa_pss_param_print(BIO *bp, RSA_PSS_PARAMS *pss, X509_ALGOR *maskHash,
         if (pss->hashAlgorithm) {
                 if (i2a_ASN1_OBJECT(bp, pss->hashAlgorithm->algorithm) <= 0)
                         goto err;
-        } else if (BIO_puts(bp, "sha1 (default)") <= 0)
+        } else if (BIO_puts(bp, "sha1 (default)") <= 0) {
                 goto err;
+        }
 
         if (BIO_puts(bp, "\n") <= 0)
                 goto err;
@@ -342,24 +348,28 @@ rsa_pss_param_print(BIO *bp, RSA_PSS_PARAMS *pss, X509_ALGOR *maskHash,
                         goto err;
                 if (BIO_puts(bp, " with ") <= 0)
                         goto err;
-                if (maskHash) {
+                maskHash = rsa_mgf1_decode(pss->maskGenAlgorithm);
+                if (maskHash != NULL) {
                         if (i2a_ASN1_OBJECT(bp, maskHash->algorithm) <= 0)
                                 goto err;
-                } else if (BIO_puts(bp, "INVALID") <= 0)
+                } else if (BIO_puts(bp, "INVALID") <= 0) {
                         goto err;
-        } else if (BIO_puts(bp, "mgf1 with sha1 (default)") <= 0)
+                }
+        } else if (BIO_puts(bp, "mgf1 with sha1 (default)") <= 0) {
                 goto err;
+        }
         BIO_puts(bp, "\n");
 
         if (!BIO_indent(bp, indent, 128))
                 goto err;
-        if (BIO_puts(bp, "Salt Length: 0x") <= 0)
+        if (BIO_printf(bp, "%s Salt Length: 0x", pss_key ? "Minimum" : "") <= 0)
                 goto err;
         if (pss->saltLength) {
                 if (i2a_ASN1_INTEGER(bp, pss->saltLength) <= 0)
                         goto err;
-        } else if (BIO_puts(bp, "14 (default)") <= 0)
+        } else if (BIO_puts(bp, "14 (default)") <= 0) {
                 goto err;
+        }
         BIO_puts(bp, "\n");
 
         if (!BIO_indent(bp, indent, 128))
@@ -369,34 +379,92 @@ rsa_pss_param_print(BIO *bp, RSA_PSS_PARAMS *pss, X509_ALGOR *maskHash,
         if (pss->trailerField) {
                 if (i2a_ASN1_INTEGER(bp, pss->trailerField) <= 0)
                         goto err;
-        } else if (BIO_puts(bp, "BC (default)") <= 0)
+        } else if (BIO_puts(bp, "BC (default)") <= 0) {
                 goto err;
+        }
         BIO_puts(bp, "\n");
 
         rv = 1;
 
-err:
+ err:
+        X509_ALGOR_free(maskHash);
         return rv;
+
+}
+
+static int
+pkey_rsa_print(BIO *bp, const EVP_PKEY *pkey, int off, int priv)
+{
+        const RSA *x = pkey->pkey.rsa;
+        char *str;
+        const char *s;
+        int ret = 0, mod_len = 0;
+
+        if (x->n != NULL)
+                mod_len = BN_num_bits(x->n);
+
+        if (!BIO_indent(bp, off, 128))
+                goto err;
+
+        if (BIO_printf(bp, "%s ", pkey_is_pss(pkey) ?  "RSA-PSS" : "RSA") <= 0)
+                goto err;
+
+        if (BIO_printf(bp, "Public-Key: (%d bit)\n", mod_len) <= 0)
+                goto err;
+        str = "Modulus:";
+        s = "Exponent:";
+        if (!ASN1_bn_print(bp, str, x->n, NULL, off))
+                goto err;
+        if (!ASN1_bn_print(bp, s, x->e, NULL, off))
+                goto err;
+        if (priv) {
+                if (!ASN1_bn_print(bp, "privateExponent:", x->d, NULL, off))
+                        goto err;
+                if (!ASN1_bn_print(bp, "prime1:", x->p, NULL, off))
+                        goto err;
+                if (!ASN1_bn_print(bp, "prime2:", x->q, NULL, off))
+                        goto err;
+                if (!ASN1_bn_print(bp, "exponent1:", x->dmp1, NULL, off))
+                        goto err;
+                if (!ASN1_bn_print(bp, "exponent2:", x->dmq1, NULL, off))
+                        goto err;
+                if (!ASN1_bn_print(bp, "coefficient:", x->iqmp, NULL, off))
+                        goto err;
+        }
+        if (pkey_is_pss(pkey) && !rsa_pss_param_print(bp, 1, x->pss, off))
+                goto err;
+        ret = 1;
+ err:
+        return ret;
+}
+
+static int
+rsa_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent, ASN1_PCTX *ctx)
+{
+        return pkey_rsa_print(bp, pkey, indent, 0);
+}
+
+static int
+rsa_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent, ASN1_PCTX *ctx)
+{
+        return pkey_rsa_print(bp, pkey, indent, 1);
 }
 
 static int
 rsa_sig_print(BIO *bp, const X509_ALGOR *sigalg, const ASN1_STRING *sig,
     int indent, ASN1_PCTX *pctx)
 {
-        if (OBJ_obj2nid(sigalg->algorithm) == NID_rsassaPss) {
+        if (OBJ_obj2nid(sigalg->algorithm) == EVP_PKEY_RSA_PSS) {
                 int rv;
-                RSA_PSS_PARAMS *pss;
-                X509_ALGOR *maskHash;
-                pss = rsa_pss_decode(sigalg, &maskHash);
-                rv = rsa_pss_param_print(bp, pss, maskHash, indent);
-                if (pss)
-                        RSA_PSS_PARAMS_free(pss);
-                if (maskHash)
-                        X509_ALGOR_free(maskHash);
+                RSA_PSS_PARAMS *pss = rsa_pss_decode(sigalg);
+
+                rv = rsa_pss_param_print(bp, 0, pss, indent);
+                RSA_PSS_PARAMS_free(pss);
                 if (!rv)
                         return 0;
-        } else if (!sig && BIO_puts(bp, "\n") <= 0)
+        } else if (!sig && BIO_puts(bp, "\n") <= 0) {
                 return 0;
+        }
         if (sig)
                 return X509_signature_dump(bp, sig, indent);
         return 1;
@@ -406,6 +474,9 @@ static int
 rsa_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
 {
         X509_ALGOR *alg = NULL;
+        const EVP_MD *md;
+        const EVP_MD *mgf1md;
+        int min_saltlen;
 
         switch (op) {
         case ASN1_PKEY_CTRL_PKCS7_SIGN:
@@ -414,12 +485,24 @@ rsa_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
                 break;
 
         case ASN1_PKEY_CTRL_PKCS7_ENCRYPT:
+                if (pkey_is_pss(pkey))
+                        return -2;
                 if (arg1 == 0)
                         PKCS7_RECIP_INFO_get0_alg(arg2, &alg);
                 break;
 
         case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
-                *(int *)arg2 = NID_sha1;
+                if (pkey->pkey.rsa->pss != NULL) {
+                        if (!rsa_pss_get_param(pkey->pkey.rsa->pss, &md, &mgf1md,
+                            &min_saltlen)) {
+                                RSAerror(ERR_R_INTERNAL_ERROR);
+                                return 0;
+                        }
+                        *(int *)arg2 = EVP_MD_type(md);
+                        /* Return of 2 indicates this MD is mandatory */
+                        return 2;
+                }
+                *(int *)arg2 = NID_sha256;
                 return 1;
 
         default:
@@ -488,7 +571,36 @@ rsa_algor_to_md(X509_ALGOR *alg)
         return md;
 }
 
-/* convert algorithm ID to EVP_MD, default SHA1 */
+/*
+ * Convert EVP_PKEY_CTX in PSS mode into corresponding algorithm parameter,
+ * suitable for setting an AlgorithmIdentifier.
+ */
+static RSA_PSS_PARAMS *
+rsa_ctx_to_pss(EVP_PKEY_CTX *pkctx)
+{
+        const EVP_MD *sigmd, *mgf1md;
+        EVP_PKEY *pk = EVP_PKEY_CTX_get0_pkey(pkctx);
+        int saltlen;
+
+        if (EVP_PKEY_CTX_get_signature_md(pkctx, &sigmd) <= 0)
+                return NULL;
+        if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
+                return NULL;
+        if (!EVP_PKEY_CTX_get_rsa_pss_saltlen(pkctx, &saltlen))
+                return NULL;
+        if (saltlen == -1) {
+                saltlen = EVP_MD_size(sigmd);
+        } else if (saltlen == -2 || saltlen == -3) {
+                saltlen = EVP_PKEY_size(pk) - EVP_MD_size(sigmd) - 2;
+                if ((EVP_PKEY_bits(pk) & 0x7) == 1)
+                        saltlen--;
+                if (saltlen < 0)
+                        return NULL;
+        }
+
+        return rsa_pss_params_create(sigmd, mgf1md, saltlen);
+}
+
 RSA_PSS_PARAMS *
 rsa_pss_params_create(const EVP_MD *sigmd, const EVP_MD *mgf1md, int saltlen)
 {
@@ -517,6 +629,78 @@ rsa_pss_params_create(const EVP_MD *sigmd, const EVP_MD *mgf1md, int saltlen)
         return NULL;
 }
 
+static ASN1_STRING *
+rsa_ctx_to_pss_string(EVP_PKEY_CTX *pkctx)
+{
+        RSA_PSS_PARAMS *pss = rsa_ctx_to_pss(pkctx);
+        ASN1_STRING *os;
+
+        if (pss == NULL)
+                return NULL;
+
+        os = ASN1_item_pack(pss, &RSA_PSS_PARAMS_it, NULL);
+        RSA_PSS_PARAMS_free(pss);
+        return os;
+}
+
+/*
+ * From PSS AlgorithmIdentifier set public key parameters. If pkey isn't NULL
+ * then the EVP_MD_CTX is setup and initialised. If it is NULL parameters are
+ * passed to pkctx instead.
+ */
+
+static int
+rsa_pss_to_ctx(EVP_MD_CTX *ctx, EVP_PKEY_CTX *pkctx,
+    X509_ALGOR *sigalg, EVP_PKEY *pkey)
+{
+        int rv = -1;
+        int saltlen;
+        const EVP_MD *mgf1md = NULL, *md = NULL;
+        RSA_PSS_PARAMS *pss;
+
+        /* Sanity check: make sure it is PSS */
+        if (OBJ_obj2nid(sigalg->algorithm) != EVP_PKEY_RSA_PSS) {
+                RSAerror(RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
+                return -1;
+        }
+        /* Decode PSS parameters */
+        pss = rsa_pss_decode(sigalg);
+
+        if (!rsa_pss_get_param(pss, &md, &mgf1md, &saltlen)) {
+                RSAerror(RSA_R_INVALID_PSS_PARAMETERS);
+                goto err;
+        }
+
+        /* We have all parameters now set up context */
+        if (pkey) {
+                if (!EVP_DigestVerifyInit(ctx, &pkctx, md, NULL, pkey))
+                        goto err;
+        } else {
+                const EVP_MD *checkmd;
+                if (EVP_PKEY_CTX_get_signature_md(pkctx, &checkmd) <= 0)
+                        goto err;
+                if (EVP_MD_type(md) != EVP_MD_type(checkmd)) {
+                        RSAerror(RSA_R_DIGEST_DOES_NOT_MATCH);
+                        goto err;
+                }
+        }
+
+        if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_PSS_PADDING) <= 0)
+                goto err;
+
+        if (EVP_PKEY_CTX_set_rsa_pss_saltlen(pkctx, saltlen) <= 0)
+                goto err;
+
+        if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
+                goto err;
+        /* Carry on */
+        rv = 1;
+
+ err:
+        RSA_PSS_PARAMS_free(pss);
+        return rv;
+}
+
 int
 rsa_pss_get_param(const RSA_PSS_PARAMS *pss, const EVP_MD **pmd,
     const EVP_MD **pmgf1md, int *psaltlen)
@@ -551,187 +735,56 @@ rsa_pss_get_param(const RSA_PSS_PARAMS *pss, const EVP_MD **pmd,
         return 1;
 }
 
-/* Customised RSA item verification routine. This is called
- * when a signature is encountered requiring special handling. We
- * currently only handle PSS.
+/*
+ * Customised RSA item verification routine. This is called when a signature
+ * is encountered requiring special handling. We currently only handle PSS.
  */
+
 static int
 rsa_item_verify(EVP_MD_CTX *ctx, const ASN1_ITEM *it, void *asn,
     X509_ALGOR *sigalg, ASN1_BIT_STRING *sig, EVP_PKEY *pkey)
 {
-        int rv = -1;
-        int saltlen;
-        const EVP_MD *mgf1md = NULL, *md = NULL;
-        RSA_PSS_PARAMS *pss;
-        X509_ALGOR *maskHash;
-        EVP_PKEY_CTX *pkctx;
-
         /* Sanity check: make sure it is PSS */
-        if (OBJ_obj2nid(sigalg->algorithm) != NID_rsassaPss) {
+        if (OBJ_obj2nid(sigalg->algorithm) != EVP_PKEY_RSA_PSS) {
                 RSAerror(RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
                 return -1;
         }
-
-        /* Decode PSS parameters */
-        pss = rsa_pss_decode(sigalg, &maskHash);
-
-        if (pss == NULL) {
-                RSAerror(RSA_R_INVALID_PSS_PARAMETERS);
-                goto err;
-        }
-        /* Check mask and lookup mask hash algorithm */
-        if (pss->maskGenAlgorithm) {
-                if (OBJ_obj2nid(pss->maskGenAlgorithm->algorithm) != NID_mgf1) {
-                        RSAerror(RSA_R_UNSUPPORTED_MASK_ALGORITHM);
-                        goto err;
-                }
-                if (!maskHash) {
-                        RSAerror(RSA_R_UNSUPPORTED_MASK_PARAMETER);
-                        goto err;
-                }
-                mgf1md = EVP_get_digestbyobj(maskHash->algorithm);
-                if (mgf1md == NULL) {
-                        RSAerror(RSA_R_UNKNOWN_MASK_DIGEST);
-                        goto err;
-                }
-        } else
-                mgf1md = EVP_sha1();
-
-        if (pss->hashAlgorithm) {
-                md = EVP_get_digestbyobj(pss->hashAlgorithm->algorithm);
-                if (md == NULL) {
-                        RSAerror(RSA_R_UNKNOWN_PSS_DIGEST);
-                        goto err;
-                }
-        } else
-                md = EVP_sha1();
-
-        if (pss->saltLength) {
-                saltlen = ASN1_INTEGER_get(pss->saltLength);
-
-                /* Could perform more salt length sanity checks but the main
-                 * RSA routines will trap other invalid values anyway.
-                 */
-                if (saltlen < 0) {
-                        RSAerror(RSA_R_INVALID_SALT_LENGTH);
-                        goto err;
-                }
-        } else
-                saltlen = 20;
-
-        /* low-level routines support only trailer field 0xbc (value 1)
-         * and PKCS#1 says we should reject any other value anyway.
-         */
-        if (pss->trailerField && ASN1_INTEGER_get(pss->trailerField) != 1) {
-                RSAerror(RSA_R_INVALID_TRAILER);
-                goto err;
+        if (rsa_pss_to_ctx(ctx, NULL, sigalg, pkey) > 0) {
+                /* Carry on */
+                return 2;
         }
-
-        /* We have all parameters now set up context */
-
-        if (!EVP_DigestVerifyInit(ctx, &pkctx, md, NULL, pkey))
-                goto err;
-
-        if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_PSS_PADDING) <= 0)
-                goto err;
-
-        if (EVP_PKEY_CTX_set_rsa_pss_saltlen(pkctx, saltlen) <= 0)
-                goto err;
-
-        if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
-                goto err;
-        /* Carry on */
-        rv = 2;
-
-err:
-        RSA_PSS_PARAMS_free(pss);
-        if (maskHash)
-                X509_ALGOR_free(maskHash);
-        return rv;
+        return -1;
 }
 
 static int
 rsa_item_sign(EVP_MD_CTX *ctx, const ASN1_ITEM *it, void *asn,
     X509_ALGOR *alg1, X509_ALGOR *alg2, ASN1_BIT_STRING *sig)
 {
-        int pad_mode;
         EVP_PKEY_CTX *pkctx = ctx->pctx;
+        int pad_mode;
 
         if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
                 return 0;
         if (pad_mode == RSA_PKCS1_PADDING)
                 return 2;
         if (pad_mode == RSA_PKCS1_PSS_PADDING) {
-                const EVP_MD *sigmd, *mgf1md;
-                RSA_PSS_PARAMS *pss = NULL;
-                X509_ALGOR *mgf1alg = NULL;
-                ASN1_STRING *os1 = NULL, *os2 = NULL;
-                EVP_PKEY *pk = EVP_PKEY_CTX_get0_pkey(pkctx);
-                int saltlen, rv = 0;
-
-                sigmd = EVP_MD_CTX_md(ctx);
-                if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
-                        goto err;
-                if (!EVP_PKEY_CTX_get_rsa_pss_saltlen(pkctx, &saltlen))
-                        goto err;
-                if (saltlen == -1)
-                        saltlen = EVP_MD_size(sigmd);
-                else if (saltlen == -2) {
-                        saltlen = EVP_PKEY_size(pk) - EVP_MD_size(sigmd) - 2;
-                        if (((EVP_PKEY_bits(pk) - 1) & 0x7) == 0)
-                                saltlen--;
-                }
-                pss = RSA_PSS_PARAMS_new();
-                if (!pss)
-                        goto err;
-                if (saltlen != 20) {
-                        pss->saltLength = ASN1_INTEGER_new();
-                        if (!pss->saltLength)
-                                goto err;
-                        if (!ASN1_INTEGER_set(pss->saltLength, saltlen))
-                                goto err;
-                }
-                if (EVP_MD_type(sigmd) != NID_sha1) {
-                        pss->hashAlgorithm = X509_ALGOR_new();
-                        if (!pss->hashAlgorithm)
-                                goto err;
-                        X509_ALGOR_set_md(pss->hashAlgorithm, sigmd);
-                }
-                if (EVP_MD_type(mgf1md) != NID_sha1) {
-                        ASN1_STRING *stmp = NULL;
-                        /* need to embed algorithm ID inside another */
-                        mgf1alg = X509_ALGOR_new();
-                        X509_ALGOR_set_md(mgf1alg, mgf1md);
-                        if (!ASN1_item_pack(mgf1alg, &X509_ALGOR_it,
-                            &stmp))
-                                goto err;
-                        pss->maskGenAlgorithm = X509_ALGOR_new();
-                        if (!pss->maskGenAlgorithm)
-                                goto err;
-                        X509_ALGOR_set0(pss->maskGenAlgorithm,
-                            OBJ_nid2obj(NID_mgf1), V_ASN1_SEQUENCE, stmp);
-                }
-                /* Finally create string with pss parameter encoding. */
-                if (!ASN1_item_pack(pss, &RSA_PSS_PARAMS_it, &os1))
-                        goto err;
+                ASN1_STRING *os1 = NULL;
+                os1 = rsa_ctx_to_pss_string(pkctx);
+                if (!os1)
+                        return 0;
+                /* Duplicate parameters if we have to */
                 if (alg2) {
-                        os2 = ASN1_STRING_dup(os1);
-                        if (!os2)
-                                goto err;
-                        X509_ALGOR_set0(alg2, OBJ_nid2obj(NID_rsassaPss),
+                        ASN1_STRING *os2 = ASN1_STRING_dup(os1);
+                        if (!os2) {
+                                ASN1_STRING_free(os1);
+                                return 0;
+                        }
+                        X509_ALGOR_set0(alg2, OBJ_nid2obj(EVP_PKEY_RSA_PSS),
                             V_ASN1_SEQUENCE, os2);
                 }
-                X509_ALGOR_set0(alg1, OBJ_nid2obj(NID_rsassaPss),
+                X509_ALGOR_set0(alg1, OBJ_nid2obj(EVP_PKEY_RSA_PSS),
                     V_ASN1_SEQUENCE, os1);
-                os1 = os2 = NULL;
-                rv = 3;
-err:
-                if (mgf1alg)
-                        X509_ALGOR_free(mgf1alg);
-                if (pss)
-                        RSA_PSS_PARAMS_free(pss);
-                ASN1_STRING_free(os1);
-                return rv;
+                return 3;
         }
         return 2;
 }
@@ -773,3 +826,31 @@ const EVP_PKEY_ASN1_METHOD rsa_asn1_meths[] = {
                 .pkey_flags = ASN1_PKEY_ALIAS
         }
 };
+
+const EVP_PKEY_ASN1_METHOD rsa_pss_asn1_meth = {
+        .pkey_id = EVP_PKEY_RSA_PSS,
+        .pkey_base_id = EVP_PKEY_RSA_PSS,
+        .pkey_flags = ASN1_PKEY_SIGPARAM_NULL,
+
+        .pem_str = "RSA-PSS",
+        .info = "OpenSSL RSA-PSS method",
+
+        .pub_decode = rsa_pub_decode,
+        .pub_encode = rsa_pub_encode,
+        .pub_cmp = rsa_pub_cmp,
+        .pub_print = rsa_pub_print,
+
+        .priv_decode = rsa_priv_decode,
+        .priv_encode = rsa_priv_encode,
+        .priv_print = rsa_priv_print,
+
+        .pkey_size = int_rsa_size,
+        .pkey_bits = rsa_bits,
+
+        .sig_print = rsa_sig_print,
+
+        .pkey_free = int_rsa_free,
+        .pkey_ctrl = rsa_pkey_ctrl,
+        .item_verify = rsa_item_verify,
+        .item_sign = rsa_item_sign
+};
diff --git a/src/lib/libcrypto/rsa/rsa_err.c b/src/lib/libcrypto/rsa/rsa_err.c
index 91d74307f0..9924dac581 100644
--- a/src/lib/libcrypto/rsa/rsa_err.c
+++ b/src/lib/libcrypto/rsa/rsa_err.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: rsa_err.c,v 1.18 2019/10/31 13:56:29 jsing Exp $ */
+/* $OpenBSD: rsa_err.c,v 1.19 2019/11/01 03:45:13 jsing Exp $ */
 /* ====================================================================
  * Copyright (c) 1999-2011 The OpenSSL Project.  All rights reserved.
  *
@@ -90,6 +90,7 @@ static ERR_STRING_DATA RSA_str_reasons[] = {
         {ERR_REASON(RSA_R_DATA_TOO_LARGE_FOR_MODULUS), "data too large for modulus"},
         {ERR_REASON(RSA_R_DATA_TOO_SMALL)        , "data too small"},
         {ERR_REASON(RSA_R_DATA_TOO_SMALL_FOR_KEY_SIZE), "data too small for key size"},
+        {ERR_REASON(RSA_R_DIGEST_DOES_NOT_MATCH) , "digest does not match"},
         {ERR_REASON(RSA_R_DIGEST_NOT_ALLOWED)    , "digest not allowed"},
         {ERR_REASON(RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY), "digest too big for rsa key"},
         {ERR_REASON(RSA_R_DMP1_NOT_CONGRUENT_TO_D), "dmp1 not congruent to d"},
diff --git a/src/lib/libcrypto/rsa/rsa_locl.h b/src/lib/libcrypto/rsa/rsa_locl.h
index d69946f95c..621c89dc76 100644
--- a/src/lib/libcrypto/rsa/rsa_locl.h
+++ b/src/lib/libcrypto/rsa/rsa_locl.h
@@ -1,9 +1,13 @@
-/* $OpenBSD: rsa_locl.h,v 1.8 2019/10/31 13:56:29 jsing Exp $ */
+/* $OpenBSD: rsa_locl.h,v 1.9 2019/11/01 03:45:13 jsing Exp $ */
 
 __BEGIN_HIDDEN_DECLS
 
 #define RSA_MIN_MODULUS_BITS    512
 
+/* Macros to test if a pkey or ctx is for a PSS key */
+#define pkey_is_pss(pkey) (pkey->ameth->pkey_id == EVP_PKEY_RSA_PSS)
+#define pkey_ctx_is_pss(ctx) (ctx->pmeth->pkey_id == EVP_PKEY_RSA_PSS)
+
 RSA_PSS_PARAMS *rsa_pss_params_create(const EVP_MD *sigmd, const EVP_MD *mgf1md,
     int saltlen);
 int rsa_pss_get_param(const RSA_PSS_PARAMS *pss, const EVP_MD **pmd,