Check for NULL pointers in channels.c

1 files changed, 37 insertions, 5 deletions

diff --git a/src/channels.c b/src/channels.c
index 214485c9..e51282fc 100644
--- a/src/channels.c
+++ b/src/channels.c
@@ -79,6 +79,10 @@ static ssh_channel channel_from_msg(ssh_session session, ssh_buffer packet);
 ssh_channel ssh_channel_new(ssh_session session) {
   ssh_channel channel = NULL;
 
+  if(session == NULL) {
+      return NULL;
+  }
+
   channel = malloc(sizeof(struct ssh_channel_struct));
   if (channel == NULL) {
     ssh_set_error_oom(session);
@@ -887,6 +891,10 @@ int channel_default_bufferize(ssh_channel channel, void *data, int len,
  * @see channel_request_exec()
  */
 int ssh_channel_open_session(ssh_channel channel) {
+  if(channel == NULL) {
+      return SSH_ERROR;
+  }
+
 #ifdef WITH_SSH1
   if (channel->session->version == 1) {
     return channel_open_session1(channel);
@@ -934,7 +942,6 @@ int ssh_channel_open_forward(ssh_channel channel, const char *remotehost,
   }
 
   session = channel->session;
-
   enter_function();
 
   if(remotehost == NULL || sourcehost == NULL) {
@@ -1036,9 +1043,14 @@ void ssh_channel_free(ssh_channel channel) {
  * @see channel_free()
  */
 int ssh_channel_send_eof(ssh_channel channel){
-  ssh_session session = channel->session;
+  ssh_session session;
   int rc = SSH_ERROR;
 
+  if(channel == NULL) {
+      return rc;
+  }
+
+  session = channel->session;
   enter_function();
 
   if (buffer_add_u8(session->out_buffer, SSH2_MSG_CHANNEL_EOF) < 0) {
@@ -1080,9 +1092,14 @@ error:
  * @see channel_eof()
  */
 int ssh_channel_close(ssh_channel channel){
-  ssh_session session = channel->session;
+  ssh_session session;
   int rc = 0;
 
+  if(channel == NULL) {
+    return SSH_ERROR;
+  }
+
+  session = channel->session;
   enter_function();
 
   if (channel->local_eof == 0) {
@@ -1143,6 +1160,10 @@ int channel_write_common(ssh_channel channel, const void *data,
       return SSH_ERROR;
   }
 
+  if(channel == NULL || data == NULL) {
+      return -1;
+  }
+  session = channel->session;
   enter_function();
   if(ssh_is_blocking(session))
     timeout = -2;
@@ -2823,11 +2844,17 @@ int ssh_channel_write_stderr(ssh_channel channel, const void *data, uint32_t len
  */
 int ssh_channel_open_reverse_forward(ssh_channel channel, const char *remotehost,
     int remoteport, const char *sourcehost, int localport) {
-  ssh_session session = channel->session;
+  ssh_session session;
   ssh_buffer payload = NULL;
   ssh_string str = NULL;
   int rc = SSH_ERROR;
 
+  if(channel == NULL) {
+      return rc;
+  }
+
+  session = channel->session;
+
   enter_function();
 
   payload = ssh_buffer_new();
@@ -2891,6 +2918,10 @@ int ssh_channel_request_send_exit_status(ssh_channel channel, int exit_status) {
   ssh_buffer buffer = NULL;
   int rc = SSH_ERROR;
 
+  if(channel == NULL) {
+      return SSH_ERROR;
+  }
+
 #ifdef WITH_SSH1
   if (channel->version == 1) {
     return SSH_ERROR; // TODO: Add support for SSH-v1 if possible.
@@ -2933,7 +2964,8 @@ error:
  * @return              SSH_OK on success, SSH_ERROR if an error occured
  *                      (including attempts to send signal via SSH-v1 session).
  */
-int ssh_channel_request_send_exit_signal(ssh_channel channel, const char *sig, int core, const char *errmsg, const char *lang) {
+int ssh_channel_request_send_exit_signal(ssh_channel channel, const char *sig,
+                            int core, const char *errmsg, const char *lang) {
   ssh_buffer buffer = NULL;
   ssh_string tmp = NULL;
   int rc = SSH_ERROR;