pki: Use consistent API for ssh_pki_export_pubkey_blob().

include/libssh/pki.h

@@ -75,7 +75,8 @@ int ssh_pki_signature_verify_blob(ssh_session session,
                                   size_t dlen);
 
 /* SSH Public Key Functions */
-ssh_string ssh_pki_export_pubkey_blob(const ssh_key key);
+int ssh_pki_export_pubkey_blob(const ssh_key key,
+                               ssh_string *pblob);
 int ssh_pki_import_pubkey_blob(const ssh_string key_blob,
                                ssh_key *pkey);
 

src/agent.c

@@ -441,8 +441,8 @@ ssh_string ssh_agent_sign_data(ssh_session session,
         return NULL;
     }
 
-    key_blob = ssh_pki_export_pubkey_blob(pubkey);
-    if (key_blob == NULL) {
+    rc = ssh_pki_export_pubkey_blob(pubkey, &key_blob);
+    if (rc < 0) {
         ssh_buffer_free(request);
         return NULL;
     }

src/auth.c

@@ -601,8 +601,8 @@ int ssh_userauth_try_publickey(ssh_session session,
     }
 
     /* public key */
-    str = ssh_pki_export_pubkey_blob(pubkey);
-    if (str == NULL) {
+    rc = ssh_pki_export_pubkey_blob(pubkey, &str);
+    if (rc < 0) {
         goto fail;
     }
 
@@ -763,8 +763,8 @@ int ssh_userauth_publickey(ssh_session session,
     }
 
     /* public key */
-    str = ssh_pki_export_pubkey_blob(privkey);
-    if (str == NULL) {
+    rc = ssh_pki_export_pubkey_blob(privkey, &str);
+    if (rc < 0) {
         goto fail;
     }
 
@@ -899,8 +899,8 @@ static int ssh_userauth_agent_publickey(ssh_session session,
     }
 
     /* public key */
-    str = ssh_pki_export_pubkey_blob(pubkey);
-    if (str == NULL) {
+    rc = ssh_pki_export_pubkey_blob(pubkey, &str);
+    if (rc < 0) {
         goto fail;
     }
 

src/legacy.c

@@ -424,8 +424,8 @@ ssh_string publickey_from_file(ssh_session session, const char *filename,
         return NULL;
     }
 
-    key_str = ssh_pki_export_pubkey_blob(key);
-    if (key_str == NULL) {
+    rc = ssh_pki_export_pubkey_blob(key, &key_str);
+    if (rc < 0) {
         return NULL;
     }
 
@@ -477,6 +477,7 @@ ssh_public_key publickey_from_string(ssh_session session, ssh_string pubkey_s) {
 ssh_string publickey_to_string(ssh_public_key pubkey) {
     ssh_key key;
     ssh_string key_blob;
+    int rc;
 
     key = ssh_key_new();
     if (key == NULL) {
@@ -489,7 +490,10 @@ ssh_string publickey_to_string(ssh_public_key pubkey) {
     key->dsa = pubkey->dsa_pub;
     key->rsa = pubkey->rsa_pub;
 
-    key_blob = ssh_pki_export_pubkey_blob(key);
+    rc = ssh_pki_export_pubkey_blob(key, &key_blob);
+    if (rc < 0) {
+        key_blob = NULL;
+    }
 
     key->dsa = NULL;
     key->rsa = NULL;

src/messages.c

@@ -415,8 +415,8 @@ static ssh_buffer ssh_msg_userauth_build_digest(ssh_session session,
     }
 
     /* Add the publickey as blob */
-    str = ssh_pki_export_pubkey_blob(msg->auth_request.pubkey);
-    if (str == NULL) {
+    rc = ssh_pki_export_pubkey_blob(msg->auth_request.pubkey, &str);
+    if (rc < 0) {
         ssh_buffer_free(buffer);
         return NULL;
     }

src/pki.c

@@ -800,23 +800,39 @@ ssh_key ssh_pki_publickey_from_privatekey(const ssh_key privkey) {
 }
 
 /**
+ * @internal
+ *
  * @brief Create a key_blob from a public key.
  *
  * The "key_blob" is encoded as per RFC 4253 section 6.6 "Public Key
  * Algorithms" for any of the supported protocol 2 key types.
  *
- * @param[in] key       A public or private key to create the public ssh_string
+ * @param[in]  key      A public or private key to create the public ssh_string
  *                      from.
  *
- * @return              The key_blob or NULL on error.
+ * @param[out] pblob    A pointer to store the newly allocated key blob. You
+ *                      NEED to free it.
+ *
+ * @return              SSH_OK on success, SSH_ERROR otherwise.
+ *
+ * @see ssh_string_free()
  */
-ssh_string ssh_pki_export_pubkey_blob(const ssh_key key)
+int ssh_pki_export_pubkey_blob(const ssh_key key,
+                               ssh_string *pblob)
 {
+    ssh_string blob;
+
     if (key == NULL) {
-        return NULL;
+        return SSH_OK;
     }
 
-    return pki_publickey_to_blob(key);
+    blob = pki_publickey_to_blob(key);
+    if (blob == NULL) {
+        return SSH_ERROR;
+    }
+
+    *pblob = blob;
+    return SSH_OK;
 }
 
 /**

src/server.c

@@ -159,6 +159,7 @@ static int dh_handshake_server(ssh_session session) {
   ssh_string pubkey_blob;
   ssh_string sig_blob;
   ssh_string f;
+  int rc;
 
   if (dh_generate_y(session) < 0) {
     ssh_set_error(session, SSH_FATAL, "Could not create y number");
@@ -196,9 +197,9 @@ static int dh_handshake_server(ssh_session session) {
     return -1;
   }
 
-  pubkey_blob = ssh_pki_export_pubkey_blob(pubkey);
+  rc = ssh_pki_export_pubkey_blob(pubkey, &pubkey_blob);
   ssh_key_free(pubkey);
-  if (pubkey_blob == NULL) {
+  if (rc < 0) {
     ssh_set_error_oom(session);
     ssh_string_free(f);
     return -1;
@@ -960,8 +961,8 @@ int ssh_message_auth_reply_pk_ok_simple(ssh_message msg) {
         return SSH_ERROR;
     }
 
-    pubkey_blob = ssh_pki_export_pubkey_blob(msg->auth_request.pubkey);
-    if (pubkey_blob == NULL) {
+    ret = ssh_pki_export_pubkey_blob(msg->auth_request.pubkey, &pubkey_blob);
+    if (ret < 0) {
         ssh_string_free(algo);
         return SSH_ERROR;
     }