138 lines
3.1 KiB
Diff
138 lines
3.1 KiB
Diff
commit 2c3ef499bfffce3cfd315edeebf202850ba4e00a
|
|
Author: Jakub Jelen <jjelen@redhat.com>
|
|
Date: Tue Apr 16 15:35:18 2019 +0200
|
|
|
|
Use the new OpenSSL KDF
|
|
|
|
diff --git a/configure.ac b/configure.ac
|
|
index 2a455e4e..e01c3d43 100644
|
|
--- a/configure.ac
|
|
+++ b/configure.ac
|
|
@@ -2712,6 +2712,7 @@ if test "x$openssl" = "xyes" ; then
|
|
HMAC_CTX_init \
|
|
RSA_generate_key_ex \
|
|
RSA_get_default_method \
|
|
+ EVP_KDF_CTX_new_id \
|
|
])
|
|
|
|
# OpenSSL_add_all_algorithms may be a macro.
|
|
diff --git a/kex.c b/kex.c
|
|
index b6f041f4..1fbce2bb 100644
|
|
--- a/kex.c
|
|
+++ b/kex.c
|
|
@@ -38,6 +38,9 @@
|
|
#ifdef WITH_OPENSSL
|
|
#include <openssl/crypto.h>
|
|
#include <openssl/dh.h>
|
|
+# ifdef HAVE_EVP_KDF_CTX_NEW_ID
|
|
+# include <openssl/kdf.h>
|
|
+# endif
|
|
#endif
|
|
|
|
#include "ssh.h"
|
|
@@ -942,6 +945,95 @@ kex_choose_conf(struct ssh *ssh)
|
|
return r;
|
|
}
|
|
|
|
+#ifdef HAVE_EVP_KDF_CTX_NEW_ID
|
|
+static const EVP_MD *
|
|
+digest_to_md(int digest_type)
|
|
+{
|
|
+ switch (digest_type) {
|
|
+ case SSH_DIGEST_SHA1:
|
|
+ return EVP_sha1();
|
|
+ case SSH_DIGEST_SHA256:
|
|
+ return EVP_sha256();
|
|
+ case SSH_DIGEST_SHA384:
|
|
+ return EVP_sha384();
|
|
+ case SSH_DIGEST_SHA512:
|
|
+ return EVP_sha512();
|
|
+ }
|
|
+ return NULL;
|
|
+}
|
|
+
|
|
+static int
|
|
+derive_key(struct ssh *ssh, int id, u_int need, u_char *hash, u_int hashlen,
|
|
+ const struct sshbuf *shared_secret, u_char **keyp)
|
|
+{
|
|
+ struct kex *kex = ssh->kex;
|
|
+ EVP_KDF_CTX *ctx = NULL;
|
|
+ u_char *key = NULL;
|
|
+ int r, key_len;
|
|
+
|
|
+ if ((key_len = ssh_digest_bytes(kex->hash_alg)) == 0)
|
|
+ return SSH_ERR_INVALID_ARGUMENT;
|
|
+ key_len = ROUNDUP(need, key_len);
|
|
+ if ((key = calloc(1, key_len)) == NULL) {
|
|
+ r = SSH_ERR_ALLOC_FAIL;
|
|
+ goto out;
|
|
+ }
|
|
+
|
|
+ ctx = EVP_KDF_CTX_new_id(EVP_KDF_SSHKDF);
|
|
+ if (!ctx) {
|
|
+ r = SSH_ERR_LIBCRYPTO_ERROR;
|
|
+ goto out;
|
|
+ }
|
|
+
|
|
+ r = EVP_KDF_ctrl(ctx, EVP_KDF_CTRL_SET_MD, digest_to_md(kex->hash_alg));
|
|
+ if (r != 1) {
|
|
+ r = SSH_ERR_LIBCRYPTO_ERROR;
|
|
+ goto out;
|
|
+ }
|
|
+ r = EVP_KDF_ctrl(ctx, EVP_KDF_CTRL_SET_KEY,
|
|
+ sshbuf_ptr(shared_secret), sshbuf_len(shared_secret));
|
|
+ if (r != 1) {
|
|
+ r = SSH_ERR_LIBCRYPTO_ERROR;
|
|
+ goto out;
|
|
+ }
|
|
+ r = EVP_KDF_ctrl(ctx, EVP_KDF_CTRL_SET_SSHKDF_XCGHASH, hash, hashlen);
|
|
+ if (r != 1) {
|
|
+ r = SSH_ERR_LIBCRYPTO_ERROR;
|
|
+ goto out;
|
|
+ }
|
|
+ r = EVP_KDF_ctrl(ctx, EVP_KDF_CTRL_SET_SSHKDF_TYPE, id);
|
|
+ if (r != 1) {
|
|
+ r = SSH_ERR_LIBCRYPTO_ERROR;
|
|
+ goto out;
|
|
+ }
|
|
+ r = EVP_KDF_ctrl(ctx, EVP_KDF_CTRL_SET_SSHKDF_SESSION_ID,
|
|
+ sshbuf_ptr(kex->session_id), sshbuf_len(kex->session_id));
|
|
+ if (r != 1) {
|
|
+ r = SSH_ERR_LIBCRYPTO_ERROR;
|
|
+ goto out;
|
|
+ }
|
|
+ r = EVP_KDF_derive(ctx, key, key_len);
|
|
+ if (r != 1) {
|
|
+ r = SSH_ERR_LIBCRYPTO_ERROR;
|
|
+ goto out;
|
|
+ }
|
|
+#ifdef DEBUG_KEX
|
|
+ fprintf(stderr, "key '%c'== ", id);
|
|
+ dump_digest("key", key, key_len);
|
|
+#endif
|
|
+ *keyp = key;
|
|
+ key = NULL;
|
|
+ r = 0;
|
|
+
|
|
+out:
|
|
+ free (key);
|
|
+ EVP_KDF_CTX_free(ctx);
|
|
+ if (r < 0) {
|
|
+ return r;
|
|
+ }
|
|
+ return 0;
|
|
+}
|
|
+#else
|
|
static int
|
|
derive_key(struct ssh *ssh, int id, u_int need, u_char *hash, u_int hashlen,
|
|
const struct sshbuf *shared_secret, u_char **keyp)
|
|
@@ -1004,6 +1096,7 @@ derive_key(struct ssh *ssh, int id, u_int need, u_char *hash, u_int hashlen,
|
|
ssh_digest_free(hashctx);
|
|
return r;
|
|
}
|
|
+#endif /* HAVE_OPENSSL_EVP_KDF_CTX_NEW_ID */
|
|
|
|
#define NKEYS 6
|
|
int
|
|
|