upstream: cleanup pkcs#11 client code: use sshkey_new in instead

of stack- allocating a sshkey

work by markus@, ok djm@

OpenBSD-Commit-ID: a048eb6ec8aa7fa97330af927022c0da77521f91

1 files changed, 42 insertions, 23 deletions

diff --git a/ssh-pkcs11-client.c b/ssh-pkcs11-client.c
index de5aa8305..6cecf4863 100644
--- a/ssh-pkcs11-client.c
+++ b/ssh-pkcs11-client.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-pkcs11-client.c,v 1.13 2019/01/20 22:54:30 djm Exp $ */
+/* $OpenBSD: ssh-pkcs11-client.c,v 1.14 2019/01/20 22:57:45 djm Exp $ */
 /*
  * Copyright (c) 2010 Markus Friedl.  All rights reserved.
  * Copyright (c) 2014 Pedro Martelletto. All rights reserved.
@@ -117,19 +117,25 @@ pkcs11_terminate(void)
 static int
 rsa_encrypt(int flen, const u_char *from, u_char *to, RSA *rsa, int padding)
 {
-        struct sshkey key;      /* XXX */
-        u_char *blob, *signature = NULL;
+        struct sshkey *key = NULL;
+        struct sshbuf *msg = NULL;
+        u_char *blob = NULL, *signature = NULL;
         size_t blen, slen = 0;
         int r, ret = -1;
-        struct sshbuf *msg;
 
         if (padding != RSA_PKCS1_PADDING)
-                return (-1);
-        key.type = KEY_RSA;
-        key.rsa = rsa;
-        if ((r = sshkey_to_blob(&key, &blob, &blen)) != 0) {
+                goto fail;
+        key = sshkey_new(KEY_UNSPEC);
+        if (key == NULL) {
+                error("%s: sshkey_new failed", __func__);
+                goto fail;
+        }
+        key->type = KEY_RSA;
+        RSA_up_ref(rsa);
+        key->rsa = rsa;
+        if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) {
                 error("%s: sshkey_to_blob: %s", __func__, ssh_err(r));
-                return -1;
+                goto fail;
         }
         if ((msg = sshbuf_new()) == NULL)
                 fatal("%s: sshbuf_new failed", __func__);
@@ -138,7 +144,6 @@ rsa_encrypt(int flen, const u_char *from, u_char *to, RSA *rsa, int padding)
             (r = sshbuf_put_string(msg, from, flen)) != 0 ||
             (r = sshbuf_put_u32(msg, 0)) != 0)
                 fatal("%s: buffer error: %s", __func__, ssh_err(r));
-        free(blob);
         send_msg(msg);
         sshbuf_reset(msg);
 
@@ -151,6 +156,9 @@ rsa_encrypt(int flen, const u_char *from, u_char *to, RSA *rsa, int padding)
                 }
                 free(signature);
         }
+ fail:
+        free(blob);
+        sshkey_free(key);
         sshbuf_free(msg);
         return (ret);
 }
@@ -159,24 +167,33 @@ static ECDSA_SIG *
 ecdsa_do_sign(const unsigned char *dgst, int dgst_len, const BIGNUM *inv,
     const BIGNUM *rp, EC_KEY *ec)
 {
-        struct sshkey key; /* XXX */
-        u_char *blob, *signature = NULL;
+        struct sshkey *key = NULL;
+        struct sshbuf *msg = NULL;
+        ECDSA_SIG *ret = NULL;
         const u_char *cp;
+        u_char *blob = NULL, *signature = NULL;
         size_t blen, slen = 0;
-        ECDSA_SIG *ret = NULL;
-        struct sshbuf *msg;
-        int r;
+        int r, nid;
 
-        key.type = KEY_ECDSA;
-        key.ecdsa = ec;
-        key.ecdsa_nid = sshkey_ecdsa_key_to_nid(ec);
-        if (key.ecdsa_nid < 0) {
+        nid = sshkey_ecdsa_key_to_nid(ec);
+        if (nid < 0) {
                 error("%s: couldn't get curve nid", __func__);
-                return (NULL);
+                goto fail;
+        }
+
+        key = sshkey_new(KEY_UNSPEC);
+        if (key == NULL) {
+                error("%s: sshkey_new failed", __func__);
+                goto fail;
         }
-        if ((r = sshkey_to_blob(&key, &blob, &blen)) != 0) {
+        key->ecdsa = ec;
+        key->ecdsa_nid = nid;
+        key->type = KEY_ECDSA;
+        EC_KEY_up_ref(ec);
+
+        if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) {
                 error("%s: sshkey_to_blob: %s", __func__, ssh_err(r));
-                return (NULL);
+                goto fail;
         }
         if ((msg = sshbuf_new()) == NULL)
                 fatal("%s: sshbuf_new failed", __func__);
@@ -185,7 +202,6 @@ ecdsa_do_sign(const unsigned char *dgst, int dgst_len, const BIGNUM *inv,
             (r = sshbuf_put_string(msg, dgst, dgst_len)) != 0 ||
             (r = sshbuf_put_u32(msg, 0)) != 0)
                 fatal("%s: buffer error: %s", __func__, ssh_err(r));
-        free(blob);
         send_msg(msg);
         sshbuf_reset(msg);
 
@@ -197,6 +213,9 @@ ecdsa_do_sign(const unsigned char *dgst, int dgst_len, const BIGNUM *inv,
                 free(signature);
         }
 
+ fail:
+        free(blob);
+        sshkey_free(key);
         sshbuf_free(msg);
         return (ret);
 }