Update our EVP_PKEY_METHODs to get low level keys via public APIs

It is possible to call built-in EVP_PKEY_METHOD functions with a provided
key. For example this might occur if a custom EVP_PKEY_METHOD is in use
that wraps a built-in EVP_PKEY_METHOD. Therefore our EVP_PKEY_METHOD
functions should not assume that we are using a legacy key. Instead we
get the low level key using EVP_PKEY_get0_RSA() or other similar functions.
This "does the right thing" if the key is actually provided.

Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/16118)

diff --git a/crypto/dh/dh_pmeth.c b/crypto/dh/dh_pmeth.c
index f742bf75cfb5557e6d5555a55a20fa081f3de5ed..1ad50b850d6e02667a9f5231ea7043ee35862e6f 100644 (file)
--- a/crypto/dh/dh_pmeth.c
+++ b/crypto/dh/dh_pmeth.c
@@ -392,7 +392,7 @@ static int pkey_dh_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
     /* Note: if error return, pkey is freed by parent routine */
     if (ctx->pkey != NULL && !EVP_PKEY_copy_parameters(pkey, ctx->pkey))
         return 0;
-    return DH_generate_key(pkey->pkey.dh);
+    return DH_generate_key((DH *)EVP_PKEY_get0_DH(pkey));
 }
 
 static int pkey_dh_derive(EVP_PKEY_CTX *ctx, unsigned char *key,
@@ -408,7 +408,7 @@ static int pkey_dh_derive(EVP_PKEY_CTX *ctx, unsigned char *key,
         ERR_raise(ERR_LIB_DH, DH_R_KEYS_NOT_SET);
         return 0;
     }
-    dh = ctx->pkey->pkey.dh;
+    dh = (DH *)EVP_PKEY_get0_DH(ctx->pkey);
     dhpub = EVP_PKEY_get0_DH(ctx->peerkey);
     if (dhpub == NULL) {
         ERR_raise(ERR_LIB_DH, DH_R_KEYS_NOT_SET);

diff --git a/crypto/dsa/dsa_pmeth.c b/crypto/dsa/dsa_pmeth.c
index ffb19da580a0b7f7b5e20676924bbdb59b909508..ba6be720a296d5d5a27ab5e2a265911a9498be67 100644 (file)
--- a/crypto/dsa/dsa_pmeth.c
+++ b/crypto/dsa/dsa_pmeth.c
@@ -81,7 +81,12 @@ static int pkey_dsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
     int ret;
     unsigned int sltmp;
     DSA_PKEY_CTX *dctx = ctx->data;
-    DSA *dsa = ctx->pkey->pkey.dsa;
+    /*
+     * Discard const. Its marked as const because this may be a cached copy of
+     * the "real" key. These calls don't make any modifications that need to
+     * be reflected back in the "original" key.
+     */
+    DSA *dsa = (DSA *)EVP_PKEY_get0_DSA(ctx->pkey);
 
     if (dctx->md != NULL && tbslen != (size_t)EVP_MD_get_size(dctx->md))
         return 0;
@@ -100,7 +105,12 @@ static int pkey_dsa_verify(EVP_PKEY_CTX *ctx,
 {
     int ret;
     DSA_PKEY_CTX *dctx = ctx->data;
-    DSA *dsa = ctx->pkey->pkey.dsa;
+    /*
+     * Discard const. Its marked as const because this may be a cached copy of
+     * the "real" key. These calls don't make any modifications that need to
+     * be reflected back in the "original" key.
+     */
+    DSA *dsa = (DSA *)EVP_PKEY_get0_DSA(ctx->pkey);
 
     if (dctx->md != NULL && tbslen != (size_t)EVP_MD_get_size(dctx->md))
         return 0;
@@ -245,7 +255,7 @@ static int pkey_dsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
     /* Note: if error return, pkey is freed by parent routine */
     if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
         return 0;
-    return DSA_generate_key(pkey->pkey.dsa);
+    return DSA_generate_key((DSA *)EVP_PKEY_get0_DSA(pkey));
 }
 
 static const EVP_PKEY_METHOD dsa_pkey_meth = {

diff --git a/crypto/ec/ec_pmeth.c b/crypto/ec/ec_pmeth.c
index ce658e14ca206b843a42e1206f73dab38d2fb1ba..19e2f0d0c04d0f13882c56708d698ede70b7b271 100644 (file)
--- a/crypto/ec/ec_pmeth.c
+++ b/crypto/ec/ec_pmeth.c
@@ -109,7 +109,12 @@ static int pkey_ec_sign(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen,
     int ret, type;
     unsigned int sltmp;
     EC_PKEY_CTX *dctx = ctx->data;
-    EC_KEY *ec = ctx->pkey->pkey.ec;
+    /*
+     * Discard const. Its marked as const because this may be a cached copy of
+     * the "real" key. These calls don't make any modifications that need to
+     * be reflected back in the "original" key.
+     */
+    EC_KEY *ec = (EC_KEY *)EVP_PKEY_get0_EC_KEY(ctx->pkey);
     const int sig_sz = ECDSA_size(ec);
 
     /* ensure cast to size_t is safe */
@@ -142,7 +147,12 @@ static int pkey_ec_verify(EVP_PKEY_CTX *ctx,
 {
     int ret, type;
     EC_PKEY_CTX *dctx = ctx->data;
-    EC_KEY *ec = ctx->pkey->pkey.ec;
+    /*
+     * Discard const. Its marked as const because this may be a cached copy of
+     * the "real" key. These calls don't make any modifications that need to
+     * be reflected back in the "original" key.
+     */
+    EC_KEY *ec = (EC_KEY *)EVP_PKEY_get0_EC_KEY(ctx->pkey);
 
     if (dctx->md)
         type = EVP_MD_get_type(dctx->md);
@@ -174,7 +184,8 @@ static int pkey_ec_derive(EVP_PKEY_CTX *ctx, unsigned char *key, size_t *keylen)
         return 0;
     }
 
-    eckey = dctx->co_key ? dctx->co_key : ctx->pkey->pkey.ec;
+    eckey = dctx->co_key ? dctx->co_key
+                         : (EC_KEY *)EVP_PKEY_get0_EC_KEY(ctx->pkey);
 
     if (!key) {
         const EC_GROUP *group;
@@ -266,14 +277,23 @@ static int pkey_ec_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
             if (dctx->cofactor_mode != -1)
                 return dctx->cofactor_mode;
             else {
-                EC_KEY *ec_key = ctx->pkey->pkey.ec;
+                const EC_KEY *ec_key = EVP_PKEY_get0_EC_KEY(ctx->pkey);
                 return EC_KEY_get_flags(ec_key) & EC_FLAG_COFACTOR_ECDH ? 1 : 0;
             }
         } else if (p1 < -1 || p1 > 1)
             return -2;
         dctx->cofactor_mode = p1;
         if (p1 != -1) {
-            EC_KEY *ec_key = ctx->pkey->pkey.ec;
+            EC_KEY *ec_key = (EC_KEY *)EVP_PKEY_get0_EC_KEY(ctx->pkey);
+
+            /*
+             * We discarded the "const" above. This will only work if the key is
+             * a "real" legacy key, and not a cached copy of a provided key
+             */
+            if (evp_pkey_is_provided(ctx->pkey)) {
+                ERR_raise(ERR_LIB_EC, ERR_R_UNSUPPORTED);
+                return 0;
+            }
             if (!ec_key->group)
                 return -2;
             /* If cofactor is 1 cofactor mode does nothing */

diff --git a/crypto/ec/ecx_meth.c b/crypto/ec/ecx_meth.c
index c4bbb0a53517310e4e2e203e215208320de5c7da..9098decf2f55111f0f6675de200e7ada8668b29d 100644 (file)
--- a/crypto/ec/ecx_meth.c
+++ b/crypto/ec/ecx_meth.c
@@ -732,8 +732,8 @@ static int validate_ecx_derive(EVP_PKEY_CTX *ctx, unsigned char *key,
         ERR_raise(ERR_LIB_EC, EC_R_KEYS_NOT_SET);
         return 0;
     }
-    ecxkey = ctx->pkey->pkey.ecx;
-    peerkey = EVP_PKEY_get0(ctx->peerkey);
+    ecxkey = evp_pkey_get_legacy(ctx->pkey);
+    peerkey = evp_pkey_get_legacy(ctx->peerkey);
     if (ecxkey == NULL || ecxkey->privkey == NULL) {
         ERR_raise(ERR_LIB_EC, EC_R_INVALID_PRIVATE_KEY);
         return 0;
@@ -806,7 +806,7 @@ static int pkey_ecd_digestsign25519(EVP_MD_CTX *ctx, unsigned char *sig,
                                     size_t *siglen, const unsigned char *tbs,
                                     size_t tbslen)
 {
-    const ECX_KEY *edkey = EVP_MD_CTX_get_pkey_ctx(ctx)->pkey->pkey.ecx;
+    const ECX_KEY *edkey = evp_pkey_get_legacy(EVP_MD_CTX_get_pkey_ctx(ctx)->pkey);
 
     if (sig == NULL) {
         *siglen = ED25519_SIGSIZE;
@@ -828,7 +828,7 @@ static int pkey_ecd_digestsign448(EVP_MD_CTX *ctx, unsigned char *sig,
                                   size_t *siglen, const unsigned char *tbs,
                                   size_t tbslen)
 {
-    const ECX_KEY *edkey = EVP_MD_CTX_get_pkey_ctx(ctx)->pkey->pkey.ecx;
+    const ECX_KEY *edkey = evp_pkey_get_legacy(EVP_MD_CTX_get_pkey_ctx(ctx)->pkey);
 
     if (sig == NULL) {
         *siglen = ED448_SIGSIZE;
@@ -850,7 +850,7 @@ static int pkey_ecd_digestverify25519(EVP_MD_CTX *ctx, const unsigned char *sig,
                                       size_t siglen, const unsigned char *tbs,
                                       size_t tbslen)
 {
-    const ECX_KEY *edkey = EVP_MD_CTX_get_pkey_ctx(ctx)->pkey->pkey.ecx;
+    const ECX_KEY *edkey = evp_pkey_get_legacy(EVP_MD_CTX_get_pkey_ctx(ctx)->pkey);
 
     if (siglen != ED25519_SIGSIZE)
         return 0;
@@ -863,7 +863,7 @@ static int pkey_ecd_digestverify448(EVP_MD_CTX *ctx, const unsigned char *sig,
                                     size_t siglen, const unsigned char *tbs,
                                     size_t tbslen)
 {
-    const ECX_KEY *edkey = EVP_MD_CTX_get_pkey_ctx(ctx)->pkey->pkey.ecx;
+    const ECX_KEY *edkey = evp_pkey_get_legacy(EVP_MD_CTX_get_pkey_ctx(ctx)->pkey);
 
     if (siglen != ED448_SIGSIZE)
         return 0;
@@ -1177,7 +1177,7 @@ static int s390x_pkey_ecd_digestsign25519(EVP_MD_CTX *ctx,
         } ed25519;
         unsigned long long buff[512];
     } param;
-    const ECX_KEY *edkey = EVP_MD_CTX_get_pkey_ctx(ctx)->pkey->pkey.ecx;
+    const ECX_KEY *edkey = evp_pkey_get_legacy(EVP_MD_CTX_get_pkey_ctx(ctx)->pkey);
     int rc;
 
     if (sig == NULL) {
@@ -1217,7 +1217,7 @@ static int s390x_pkey_ecd_digestsign448(EVP_MD_CTX *ctx,
         } ed448;
         unsigned long long buff[512];
     } param;
-    const ECX_KEY *edkey = EVP_MD_CTX_get_pkey_ctx(ctx)->pkey->pkey.ecx;
+    const ECX_KEY *edkey = evp_pkey_get_legacy(EVP_MD_CTX_get_pkey_ctx(ctx)->pkey);
     int rc;
 
     if (sig == NULL) {
@@ -1260,7 +1260,7 @@ static int s390x_pkey_ecd_digestverify25519(EVP_MD_CTX *ctx,
         } ed25519;
         unsigned long long buff[512];
     } param;
-    const ECX_KEY *edkey = EVP_MD_CTX_get_pkey_ctx(ctx)->pkey->pkey.ecx;
+    const ECX_KEY *edkey = evp_pkey_get_legacy(EVP_MD_CTX_get_pkey_ctx(ctx)->pkey);
 
     if (siglen != ED25519_SIGSIZE)
         return 0;
@@ -1287,7 +1287,7 @@ static int s390x_pkey_ecd_digestverify448(EVP_MD_CTX *ctx,
         } ed448;
         unsigned long long buff[512];
     } param;
-    const ECX_KEY *edkey = EVP_MD_CTX_get_pkey_ctx(ctx)->pkey->pkey.ecx;
+    const ECX_KEY *edkey = evp_pkey_get_legacy(EVP_MD_CTX_get_pkey_ctx(ctx)->pkey);
 
     if (siglen != ED448_SIGSIZE)
         return 0;

diff --git a/crypto/rsa/rsa_pmeth.c b/crypto/rsa/rsa_pmeth.c
index 110d998ebd3b18ce84e3a732b38f6d89d1e2cd3e..44c819a5c3ce7a2f32e3686087665db2b945ac4f 100644 (file)
--- a/crypto/rsa/rsa_pmeth.c
+++ b/crypto/rsa/rsa_pmeth.c
@@ -111,7 +111,8 @@ static int setup_tbuf(RSA_PKEY_CTX *ctx, EVP_PKEY_CTX *pk)
 {
     if (ctx->tbuf != NULL)
         return 1;
-    if ((ctx->tbuf = OPENSSL_malloc(RSA_size(pk->pkey->pkey.rsa))) == NULL) {
+    if ((ctx->tbuf =
+            OPENSSL_malloc(RSA_size(EVP_PKEY_get0_RSA(pk->pkey)))) == NULL) {
         ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
         return 0;
     }
@@ -135,7 +136,12 @@ static int pkey_rsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
 {
     int ret;
     RSA_PKEY_CTX *rctx = ctx->data;
-    RSA *rsa = ctx->pkey->pkey.rsa;
+    /*
+     * Discard const. Its marked as const because this may be a cached copy of
+     * the "real" key. These calls don't make any modifications that need to
+     * be reflected back in the "original" key.
+     */
+    RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
 
     if (rctx->md) {
         if (tbslen != (size_t)EVP_MD_get_size(rctx->md)) {
@@ -147,8 +153,7 @@ static int pkey_rsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
             unsigned int sltmp;
             if (rctx->pad_mode != RSA_PKCS1_PADDING)
                 return -1;
-            ret = RSA_sign_ASN1_OCTET_STRING(0,
-                                             tbs, tbslen, sig, &sltmp, rsa);
+            ret = RSA_sign_ASN1_OCTET_STRING(0, tbs, tbslen, sig, &sltmp, rsa);
 
             if (ret <= 0)
                 return ret;
@@ -187,8 +192,7 @@ static int pkey_rsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
             return -1;
         }
     } else {
-        ret = RSA_private_encrypt(tbslen, tbs, sig, ctx->pkey->pkey.rsa,
-                                  rctx->pad_mode);
+        ret = RSA_private_encrypt(tbslen, tbs, sig, rsa, rctx->pad_mode);
     }
     if (ret < 0)
         return ret;
@@ -202,13 +206,18 @@ static int pkey_rsa_verifyrecover(EVP_PKEY_CTX *ctx,
 {
     int ret;
     RSA_PKEY_CTX *rctx = ctx->data;
+    /*
+     * Discard const. Its marked as const because this may be a cached copy of
+     * the "real" key. These calls don't make any modifications that need to
+     * be reflected back in the "original" key.
+     */
+    RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
 
     if (rctx->md) {
         if (rctx->pad_mode == RSA_X931_PADDING) {
             if (!setup_tbuf(rctx, ctx))
                 return -1;
-            ret = RSA_public_decrypt(siglen, sig,
-                                     rctx->tbuf, ctx->pkey->pkey.rsa,
+            ret = RSA_public_decrypt(siglen, sig, rctx->tbuf, rsa,
                                      RSA_X931_PADDING);
             if (ret < 1)
                 return 0;
@@ -227,7 +236,7 @@ static int pkey_rsa_verifyrecover(EVP_PKEY_CTX *ctx,
             size_t sltmp;
             ret = ossl_rsa_verify(EVP_MD_get_type(rctx->md),
                                   NULL, 0, rout, &sltmp,
-                                  sig, siglen, ctx->pkey->pkey.rsa);
+                                  sig, siglen, rsa);
             if (ret <= 0)
                 return 0;
             ret = sltmp;
@@ -235,8 +244,7 @@ static int pkey_rsa_verifyrecover(EVP_PKEY_CTX *ctx,
             return -1;
         }
     } else {
-        ret = RSA_public_decrypt(siglen, sig, rout, ctx->pkey->pkey.rsa,
-                                 rctx->pad_mode);
+        ret = RSA_public_decrypt(siglen, sig, rout, rsa, rctx->pad_mode);
     }
     if (ret < 0)
         return ret;
@@ -249,7 +257,12 @@ static int pkey_rsa_verify(EVP_PKEY_CTX *ctx,
                            const unsigned char *tbs, size_t tbslen)
 {
     RSA_PKEY_CTX *rctx = ctx->data;
-    RSA *rsa = ctx->pkey->pkey.rsa;
+    /*
+     * Discard const. Its marked as const because this may be a cached copy of
+     * the "real" key. These calls don't make any modifications that need to
+     * be reflected back in the "original" key.
+     */
+    RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
     size_t rslen;
 
     if (rctx->md) {
@@ -302,9 +315,15 @@ static int pkey_rsa_encrypt(EVP_PKEY_CTX *ctx,
 {
     int ret;
     RSA_PKEY_CTX *rctx = ctx->data;
+    /*
+     * Discard const. Its marked as const because this may be a cached copy of
+     * the "real" key. These calls don't make any modifications that need to
+     * be reflected back in the "original" key.
+     */
+    RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
 
     if (rctx->pad_mode == RSA_PKCS1_OAEP_PADDING) {
-        int klen = RSA_size(ctx->pkey->pkey.rsa);
+        int klen = RSA_size(rsa);
         if (!setup_tbuf(rctx, ctx))
             return -1;
         if (!RSA_padding_add_PKCS1_OAEP_mgf1(rctx->tbuf, klen,
@@ -313,11 +332,9 @@ static int pkey_rsa_encrypt(EVP_PKEY_CTX *ctx,
                                              rctx->oaep_labellen,
                                              rctx->md, rctx->mgf1md))
             return -1;
-        ret = RSA_public_encrypt(klen, rctx->tbuf, out,
-                                 ctx->pkey->pkey.rsa, RSA_NO_PADDING);
+        ret = RSA_public_encrypt(klen, rctx->tbuf, out, rsa, RSA_NO_PADDING);
     } else {
-        ret = RSA_public_encrypt(inlen, in, out, ctx->pkey->pkey.rsa,
-                                 rctx->pad_mode);
+        ret = RSA_public_encrypt(inlen, in, out, rsa, rctx->pad_mode);
     }
     if (ret < 0)
         return ret;
@@ -331,12 +348,17 @@ static int pkey_rsa_decrypt(EVP_PKEY_CTX *ctx,
 {
     int ret;
     RSA_PKEY_CTX *rctx = ctx->data;
+    /*
+     * Discard const. Its marked as const because this may be a cached copy of
+     * the "real" key. These calls don't make any modifications that need to
+     * be reflected back in the "original" key.
+     */
+    RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
 
     if (rctx->pad_mode == RSA_PKCS1_OAEP_PADDING) {
         if (!setup_tbuf(rctx, ctx))
             return -1;
-        ret = RSA_private_decrypt(inlen, in, rctx->tbuf,
-                                  ctx->pkey->pkey.rsa, RSA_NO_PADDING);
+        ret = RSA_private_decrypt(inlen, in, rctx->tbuf, rsa, RSA_NO_PADDING);
         if (ret <= 0)
             return ret;
         ret = RSA_padding_check_PKCS1_OAEP_mgf1(out, ret, rctx->tbuf,
@@ -345,8 +367,7 @@ static int pkey_rsa_decrypt(EVP_PKEY_CTX *ctx,
                                                 rctx->oaep_labellen,
                                                 rctx->md, rctx->mgf1md);
     } else {
-        ret = RSA_private_decrypt(inlen, in, out, ctx->pkey->pkey.rsa,
-                                  rctx->pad_mode);
+        ret = RSA_private_decrypt(inlen, in, out, rsa, rctx->pad_mode);
     }
     *outlen = constant_time_select_s(constant_time_msb_s(ret), *outlen, ret);
     ret = constant_time_select_int(constant_time_msb(ret), ret, 1);
@@ -805,7 +826,7 @@ const EVP_PKEY_METHOD *ossl_rsa_pkey_method(void)
 
 static int pkey_pss_init(EVP_PKEY_CTX *ctx)
 {
-    RSA *rsa;
+    const RSA *rsa;
     RSA_PKEY_CTX *rctx = ctx->data;
     const EVP_MD *md;
     const EVP_MD *mgf1md;
@@ -814,7 +835,7 @@ static int pkey_pss_init(EVP_PKEY_CTX *ctx)
     /* Should never happen */
     if (!pkey_ctx_is_pss(ctx))
         return 0;
-    rsa = ctx->pkey->pkey.rsa;
+    rsa = EVP_PKEY_get0_RSA(ctx->pkey);
     /* If no restrictions just return */
     if (rsa->pss == NULL)
         return 1;