certtool: allow specifying RSA-PSS parameters for key generation

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>

2 files changed, 30 insertions, 14 deletions

diff --git a/src/certtool-args.def b/src/certtool-args.def
index 2d045d1123..fcb895e829 100644
--- a/src/certtool-args.def
+++ b/src/certtool-args.def
@@ -181,7 +181,9 @@ flag = {
     name      = generate-privkey;
     value     = p;
     descrip   = "Generate a private key";
-    doc = "";
+    doc = "When generating RSA-PSS private keys, the --hash option will
+restrict the allowed hash for the key; in the same keys the --salt-size
+option is also acceptable.";
 };
 
 flag = {
@@ -564,6 +566,13 @@ flag = {
 };
 
 flag = {
+    name      = salt-size;
+    arg-type  = number;
+    descrip   = "Specify the RSA-PSS key default salt size";
+    doc = "Typical keys shouldn't set or restrict this option.";
+};
+
+flag = {
     name      = inder;
     descrip   = "Use DER format for input certificates, private keys, and DH parameters ";
     disabled;
diff --git a/src/certtool.c b/src/certtool.c
index c92095a497..e4421c2dd1 100644
--- a/src/certtool.c
+++ b/src/certtool.c
@@ -135,6 +135,8 @@ generate_private_key_int(common_info_st * cinfo)
 	int ret, key_type, bits;
 	unsigned provable = cinfo->provable;
 	unsigned flags = 0;
+	gnutls_keygen_data_st kdata[8];
+	unsigned kdata_size = 0;
 
 	key_type = req_key_type;
 
@@ -188,12 +190,15 @@ generate_private_key_int(common_info_st * cinfo)
 		}
 	}
 
-	if (cinfo->seed_size > 0) {
-		gnutls_keygen_data_st data;
+	if (HAVE_OPT(SALT_SIZE)) {
+		kdata[kdata_size].type = GNUTLS_KEYGEN_RSA_PSS_SALT_SIZE;
+		kdata[kdata_size++].size = OPT_VALUE_SALT_SIZE;
+	}
 
-		data.type = GNUTLS_KEYGEN_SEED;
-		data.data = (void*)cinfo->seed;
-		data.size = cinfo->seed_size;
+	if (cinfo->seed_size > 0) {
+		kdata[kdata_size].type = GNUTLS_KEYGEN_SEED;
+		kdata[kdata_size].data = (void*)cinfo->seed;
+		kdata[kdata_size++].size = cinfo->seed_size;
 
 		if (GNUTLS_PK_IS_RSA(key_type)) {
 			if ((bits == 3072 && cinfo->seed_size != 32) || (bits == 2048 && cinfo->seed_size != 28)) {
@@ -205,17 +210,19 @@ generate_private_key_int(common_info_st * cinfo)
 			}
 		}
 
-		ret = gnutls_x509_privkey_generate2(key, key_type, bits, GNUTLS_PRIVKEY_FLAG_PROVABLE, &data, 1);
-	} else {
-		gnutls_keygen_data_st data;
+		flags |= GNUTLS_PRIVKEY_FLAG_PROVABLE;
+	}
 
-		data.type = GNUTLS_KEYGEN_DIGEST;
-		data.size = default_dig;
+	if (default_dig) {
+		kdata[kdata_size].type = GNUTLS_KEYGEN_RSA_PSS_DIGEST;
+		kdata[kdata_size++].size = default_dig;
 
-		if (provable)
-			flags |= GNUTLS_PRIVKEY_FLAG_PROVABLE;
-		ret = gnutls_x509_privkey_generate2(key, key_type, bits, flags, &data, 1);
 	}
+
+	if (provable)
+		flags |= GNUTLS_PRIVKEY_FLAG_PROVABLE;
+
+	ret = gnutls_x509_privkey_generate2(key, key_type, bits, flags, kdata, kdata_size);
 	if (ret < 0) {
 		fprintf(stderr, "privkey_generate: %s\n",
 			gnutls_strerror(ret));