Add EVP_DigestSign/EVP_DigestVerify support for DSA

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/10013)

1 files changed, 205 insertions, 5 deletions

diff --git a/providers/common/signature/dsa.c b/providers/common/signature/dsa.c
index dc4eb6c6d4..1d6b565d38 100644
--- a/providers/common/signature/dsa.c
+++ b/providers/common/signature/dsa.c
@@ -12,18 +12,31 @@
 #include <openssl/core_names.h>
 #include <openssl/dsa.h>
 #include <openssl/params.h>
+#include <openssl/evp.h>
 #include "internal/provider_algs.h"
+#include "internal/provider_ctx.h"
 
 static OSSL_OP_signature_newctx_fn dsa_newctx;
 static OSSL_OP_signature_sign_init_fn dsa_signature_init;
 static OSSL_OP_signature_verify_init_fn dsa_signature_init;
 static OSSL_OP_signature_sign_fn dsa_sign;
+static OSSL_OP_signature_verify_fn dsa_verify;
+static OSSL_OP_signature_digest_sign_init_fn dsa_digest_signverify_init;
+static OSSL_OP_signature_digest_sign_update_fn dsa_digest_signverify_update;
+static OSSL_OP_signature_digest_sign_final_fn dsa_digest_sign_final;
+static OSSL_OP_signature_digest_verify_init_fn dsa_digest_signverify_init;
+static OSSL_OP_signature_digest_verify_update_fn dsa_digest_signverify_update;
+static OSSL_OP_signature_digest_verify_final_fn dsa_digest_verify_final;
 static OSSL_OP_signature_freectx_fn dsa_freectx;
 static OSSL_OP_signature_dupctx_fn dsa_dupctx;
 static OSSL_OP_signature_get_ctx_params_fn dsa_get_ctx_params;
 static OSSL_OP_signature_gettable_ctx_params_fn dsa_gettable_ctx_params;
 static OSSL_OP_signature_set_ctx_params_fn dsa_set_ctx_params;
 static OSSL_OP_signature_settable_ctx_params_fn dsa_settable_ctx_params;
+static OSSL_OP_signature_get_ctx_md_params_fn dsa_get_ctx_md_params;
+static OSSL_OP_signature_gettable_ctx_md_params_fn dsa_gettable_ctx_md_params;
+static OSSL_OP_signature_set_ctx_md_params_fn dsa_set_ctx_md_params;
+static OSSL_OP_signature_settable_ctx_md_params_fn dsa_settable_ctx_md_params;
 
 /*
  * What's passed as an actual key is defined by the KEYMGMT interface.
@@ -32,15 +45,24 @@ static OSSL_OP_signature_settable_ctx_params_fn dsa_settable_ctx_params;
  */
 
 typedef struct {
+    OPENSSL_CTX *libctx;
     DSA *dsa;
     size_t mdsize;
     /* Should be big enough */
     char mdname[80];
+    EVP_MD *md;
+    EVP_MD_CTX *mdctx;
 } PROV_DSA_CTX;
 
 static void *dsa_newctx(void *provctx)
 {
-    return OPENSSL_zalloc(sizeof(PROV_DSA_CTX));
+    PROV_DSA_CTX *pdsactx = OPENSSL_zalloc(sizeof(PROV_DSA_CTX));
+
+    if (pdsactx == NULL)
+        return NULL;
+
+    pdsactx->libctx = PROV_LIBRARY_CONTEXT_OF(provctx);
+    return pdsactx;
 }
 
 static int dsa_signature_init(void *vpdsactx, void *vdsa)
@@ -93,12 +115,97 @@ static int dsa_verify(void *vpdsactx, const unsigned char *sig, size_t siglen,
     return DSA_verify(0, tbs, tbslen, sig, siglen, pdsactx->dsa);
 }
 
+static int dsa_digest_signverify_init(void *vpdsactx, const char *mdname,
+                                      const char *props, void *vdsa)
+{
+    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
+    EVP_MD *md;
+
+    if (!dsa_signature_init(vpdsactx, vdsa))
+        return 0;
+
+    md = EVP_MD_fetch(pdsactx->libctx, mdname, props);
+    if (md == NULL)
+        return 0;
+    pdsactx->md = md;
+    pdsactx->mdsize = EVP_MD_size(md);
+    pdsactx->mdctx = EVP_MD_CTX_new();
+    if (pdsactx->mdctx == NULL)
+        return 0;
+
+    if (!EVP_DigestInit_ex(pdsactx->mdctx, md, NULL))
+        return 0;
+
+    return 1;
+}
+
+int dsa_digest_signverify_update(void *vpdsactx, const unsigned char *data,
+                                 size_t datalen)
+{
+    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
+
+    if (pdsactx == NULL || pdsactx->mdctx == NULL)
+        return 0;
+
+    return EVP_DigestUpdate(pdsactx->mdctx, data, datalen);
+}
+
+int dsa_digest_sign_final(void *vpdsactx, unsigned char *sig, size_t *siglen,
+                          size_t sigsize)
+{
+    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
+    unsigned char digest[EVP_MAX_MD_SIZE];
+    unsigned int dlen = 0;
+
+    if (pdsactx == NULL || pdsactx->mdctx == NULL)
+        return 0;
+
+    /*
+     * If sig is NULL then we're just finding out the sig size. Other fields
+     * are ignored. Defer to dsa_sign.
+     */
+    if (sig != NULL) {
+        /*
+         * TODO(3.0): There is the possibility that some externally provided
+         * digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
+         * but that problem is much larger than just in DSA.
+         */
+        if (!EVP_DigestFinal_ex(pdsactx->mdctx, digest, &dlen))
+            return 0;
+    }
+
+    return dsa_sign(vpdsactx, sig, siglen, sigsize, digest, (size_t)dlen);
+}
+
+
+int dsa_digest_verify_final(void *vpdsactx, const unsigned char *sig,
+                            size_t siglen)
+{
+    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
+    unsigned char digest[EVP_MAX_MD_SIZE];
+    unsigned int dlen = 0;
+
+    if (pdsactx == NULL || pdsactx->mdctx == NULL)
+        return 0;
+
+    /*
+     * TODO(3.0): There is the possibility that some externally provided
+     * digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
+     * but that problem is much larger than just in DSA.
+     */
+    if (!EVP_DigestFinal_ex(pdsactx->mdctx, digest, &dlen))
+        return 0;
+
+    return dsa_verify(vpdsactx, sig, siglen, digest, (size_t)dlen);
+}
 
 static void dsa_freectx(void *vpdsactx)
 {
     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 
     DSA_free(pdsactx->dsa);
+    EVP_MD_CTX_free(pdsactx->mdctx);
+    EVP_MD_free(pdsactx->md);
 
     OPENSSL_free(pdsactx);
 }
@@ -113,12 +220,29 @@ static void *dsa_dupctx(void *vpdsactx)
         return NULL;
 
     *dstctx = *srcctx;
-    if (dstctx->dsa != NULL && !DSA_up_ref(dstctx->dsa)) {
-        OPENSSL_free(dstctx);
-        return NULL;
+    dstctx->dsa = NULL;
+    dstctx->md = NULL;
+    dstctx->mdctx = NULL;
+
+    if (srcctx->dsa != NULL && !DSA_up_ref(srcctx->dsa))
+        goto err;
+    dstctx->dsa = srcctx->dsa;
+
+    if (srcctx->md != NULL && !EVP_MD_up_ref(srcctx->md))
+        goto err;
+    dstctx->md = srcctx->md;
+
+    if (srcctx->mdctx != NULL) {
+        dstctx->mdctx = EVP_MD_CTX_new();
+        if (dstctx->mdctx == NULL
+                || !EVP_MD_CTX_copy_ex(dstctx->mdctx, srcctx->mdctx))
+            goto err;
     }
 
     return dstctx;
+ err:
+    dsa_freectx(dstctx);
+    return NULL;
 }
 
 static int dsa_get_ctx_params(void *vpdsactx, OSSL_PARAM *params)
@@ -134,7 +258,9 @@ static int dsa_get_ctx_params(void *vpdsactx, OSSL_PARAM *params)
         return 0;
 
     p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST);
-    if (p != NULL && !OSSL_PARAM_set_utf8_string(p, pdsactx->mdname))
+    if (p != NULL && !OSSL_PARAM_set_utf8_string(p, pdsactx->md == NULL
+                                                    ? pdsactx->mdname
+                                                    : EVP_MD_name(pdsactx->md)))
         return 0;
 
     return 1;
@@ -160,6 +286,14 @@ static int dsa_set_ctx_params(void *vpdsactx, const OSSL_PARAM params[])
     if (pdsactx == NULL || params == NULL)
         return 0;
 
+    if (pdsactx->md != NULL) {
+        /*
+         * You cannot set the digest name/size when doing a DigestSign or
+         * DigestVerify.
+         */
+        return 1;
+    }
+
     p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST_SIZE);
     if (p != NULL && !OSSL_PARAM_get_size_t(p, &pdsactx->mdsize))
         return 0;
@@ -186,15 +320,73 @@ static const OSSL_PARAM known_settable_ctx_params[] = {
 
 static const OSSL_PARAM *dsa_settable_ctx_params(void)
 {
+    /*
+     * TODO(3.0): Should this function return a different set of settable ctx
+     * params if the ctx is being used for a DigestSign/DigestVerify? In that
+     * case it is not allowed to set the digest size/digest name because the
+     * digest is explicitly set as part of the init.
+     */
     return known_settable_ctx_params;
 }
 
+static int dsa_get_ctx_md_params(void *vpdsactx, OSSL_PARAM *params)
+{
+    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
+
+    if (pdsactx->mdctx == NULL)
+        return 0;
+
+    return EVP_MD_CTX_get_params(pdsactx->mdctx, params);
+}
+
+static const OSSL_PARAM *dsa_gettable_ctx_md_params(void *vpdsactx)
+{
+    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
+
+    if (pdsactx->md == NULL)
+        return 0;
+
+    return EVP_MD_gettable_ctx_params(pdsactx->md);
+}
+
+static int dsa_set_ctx_md_params(void *vpdsactx, const OSSL_PARAM params[])
+{
+    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
+
+    if (pdsactx->mdctx == NULL)
+        return 0;
+
+    return EVP_MD_CTX_set_params(pdsactx->mdctx, params);
+}
+
+static const OSSL_PARAM *dsa_settable_ctx_md_params(void *vpdsactx)
+{
+    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
+
+    if (pdsactx->md == NULL)
+        return 0;
+
+    return EVP_MD_settable_ctx_params(pdsactx->md);
+}
+
 const OSSL_DISPATCH dsa_signature_functions[] = {
     { OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))dsa_newctx },
     { OSSL_FUNC_SIGNATURE_SIGN_INIT, (void (*)(void))dsa_signature_init },
     { OSSL_FUNC_SIGNATURE_SIGN, (void (*)(void))dsa_sign },
     { OSSL_FUNC_SIGNATURE_VERIFY_INIT, (void (*)(void))dsa_signature_init },
     { OSSL_FUNC_SIGNATURE_VERIFY, (void (*)(void))dsa_verify },
+    { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
+      (void (*)(void))dsa_digest_signverify_init },
+    { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE,
+      (void (*)(void))dsa_digest_signverify_update },
+    { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL,
+      (void (*)(void))dsa_digest_sign_final },
+    { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
+      (void (*)(void))dsa_digest_signverify_init },
+    { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE,
+      (void (*)(void))dsa_digest_signverify_update },
+    { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL,
+      (void (*)(void))dsa_digest_verify_final },
     { OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))dsa_freectx },
     { OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))dsa_dupctx },
     { OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))dsa_get_ctx_params },
@@ -203,5 +395,13 @@ const OSSL_DISPATCH dsa_signature_functions[] = {
     { OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, (void (*)(void))dsa_set_ctx_params },
     { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS,
       (void (*)(void))dsa_settable_ctx_params },
+    { OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS,
+      (void (*)(void))dsa_get_ctx_md_params },
+    { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS,
+      (void (*)(void))dsa_gettable_ctx_md_params },
+    { OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS,
+      (void (*)(void))dsa_set_ctx_md_params },
+    { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS,
+      (void (*)(void))dsa_settable_ctx_md_params },
     { 0, NULL }
 };