Fixed a bunch of smallish bugs

http://linuxtesting.org/upstream-tracker/test_results/libssh/current/test_results.html
for a whole list

src/auth.c

@@ -423,6 +423,12 @@ int ssh_userauth_offer_pubkey(ssh_session session, const char *username,
   ssh_string algo = NULL;
   int rc = SSH_AUTH_ERROR;
 
+  if(session==NULL)
+    return SSH_AUTH_ERROR;
+  if(publickey==NULL){
+    ssh_set_error(session,SSH_FATAL,"invalid arguments");
+    return SSH_AUTH_ERROR;
+  }
   enter_function();
 
 #ifdef WITH_SSH1
@@ -540,6 +546,12 @@ int ssh_userauth_pubkey(ssh_session session, const char *username,
   ssh_string pkstr = NULL;
   int rc = SSH_AUTH_ERROR;
 
+  if(session==NULL)
+    return SSH_AUTH_ERROR;
+  if(privatekey==NULL){
+    ssh_set_error(session,SSH_FATAL,"invalid arguments");
+    return SSH_AUTH_ERROR;
+  }
   enter_function();
 
 #if 0
@@ -1583,6 +1595,8 @@ int ssh_userauth_kbdint(ssh_session session, const char *user,
  * @returns             The number of prompts.
  */
 int ssh_userauth_kbdint_getnprompts(ssh_session session) {
+  if(session==NULL || session->kbdint == NULL)
+	  return SSH_ERROR;
   return session->kbdint->nprompts;
 }
 
@@ -1597,6 +1611,8 @@ int ssh_userauth_kbdint_getnprompts(ssh_session session) {
  * @returns             The name of the message block. Do not free it.
  */
 const char *ssh_userauth_kbdint_getname(ssh_session session) {
+  if(session==NULL || session->kbdint == NULL)
+    return NULL;
   return session->kbdint->name;
 }
 
@@ -1612,6 +1628,8 @@ const char *ssh_userauth_kbdint_getname(ssh_session session) {
  */
 
 const char *ssh_userauth_kbdint_getinstruction(ssh_session session) {
+	if(session==NULL || session->kbdint == NULL)
+		return NULL;
   return session->kbdint->instruction;
 }
 
@@ -1633,7 +1651,9 @@ const char *ssh_userauth_kbdint_getinstruction(ssh_session session) {
  */
 const char *ssh_userauth_kbdint_getprompt(ssh_session session, unsigned int i,
     char *echo) {
-  if (i > session->kbdint->nprompts) {
+  if(session==NULL || session->kbdint == NULL)
+    return NULL;
+	if (i > session->kbdint->nprompts) {
     return NULL;
   }
 
@@ -1660,7 +1680,8 @@ const char *ssh_userauth_kbdint_getprompt(ssh_session session, unsigned int i,
  */
 int ssh_userauth_kbdint_setanswer(ssh_session session, unsigned int i,
     const char *answer) {
-  if (session == NULL || answer == NULL || i > session->kbdint->nprompts) {
+  if (session == NULL || answer == NULL || session->kbdint == NULL ||
+      i > session->kbdint->nprompts) {
     return -1;
   }
 

src/dh.c

@@ -832,23 +832,24 @@ int ssh_get_pubkey_hash(ssh_session session, unsigned char **hash) {
   unsigned char *h;
 
   if (session == NULL || hash == NULL) {
-    return -1;
+    return SSH_ERROR;
   }
   *hash = NULL;
   if (session->current_crypto == NULL ||
       session->current_crypto->server_pubkey == NULL){
     ssh_set_error(session,SSH_FATAL,"No current cryptographic context");
+    return SSH_ERROR;
   }
 
   h = malloc(sizeof(unsigned char *) * MD5_DIGEST_LEN);
   if (h == NULL) {
-    return -1;
+    return SSH_ERROR;
   }
 
   ctx = md5_init();
   if (ctx == NULL) {
     SAFE_FREE(h);
-    return -1;
+    return SSH_ERROR;
   }
 
   pubkey = session->current_crypto->server_pubkey;
@@ -877,6 +878,10 @@ void ssh_clean_pubkey_hash(unsigned char **hash) {
 }
 
 ssh_string ssh_get_pubkey(ssh_session session){
+	if(session==NULL || session->current_crypto ==NULL ||
+      session->current_crypto->server_pubkey==NULL)
+    return NULL;
+	else
     return ssh_string_copy(session->current_crypto->server_pubkey);
 }
 

src/keyfiles.c

@@ -802,7 +802,7 @@ ssh_private_key privatekey_from_file(ssh_session session, const char *filename,
 #endif
     return NULL;
   }
-
+  ZERO_STRUCTP(privkey);
   privkey->type = type;
   privkey->dsa_priv = dsa;
   privkey->rsa_priv = rsa;
@@ -955,23 +955,28 @@ int ssh_publickey_to_file(ssh_session session, const char *file,
   unsigned char *pubkey_64;
   size_t len;
   int rc;
-
+  if(session==NULL)
+  	return SSH_ERROR;
+  if(file==NULL || pubkey==NULL){
+  	ssh_set_error(session, SSH_FATAL, "Invalid parameters");
+  	return SSH_ERROR;
+  }
   pubkey_64 = bin_to_base64(pubkey->string, ssh_string_len(pubkey));
   if (pubkey_64 == NULL) {
-    return -1;
+    return SSH_ERROR;
   }
 
   user = ssh_get_local_username(session);
   if (user == NULL) {
     SAFE_FREE(pubkey_64);
-    return -1;
+    return SSH_ERROR;
   }
 
   rc = gethostname(host, sizeof(host));
   if (rc < 0) {
     SAFE_FREE(user);
     SAFE_FREE(pubkey_64);
-    return -1;
+    return SSH_ERROR;
   }
 
   snprintf(buffer, sizeof(buffer), "%s %s %s@%s\n",
@@ -990,7 +995,7 @@ int ssh_publickey_to_file(ssh_session session, const char *file,
   if (fp == NULL) {
     ssh_set_error(session, SSH_REQUEST_DENIED,
         "Error opening %s: %s", file, strerror(errno));
-    return -1;
+    return SSH_ERROR;
   }
 
   len = strlen(buffer);
@@ -999,11 +1004,11 @@ int ssh_publickey_to_file(ssh_session session, const char *file,
         "Unable to write to %s", file);
     fclose(fp);
     unlink(file);
-    return -1;
+    return SSH_ERROR;
   }
 
   fclose(fp);
-  return 0;
+  return SSH_OK;
 }
 
 /**

src/keys.c

@@ -329,7 +329,7 @@ ssh_public_key publickey_from_privatekey(ssh_private_key prv) {
   if (key == NULL) {
     return NULL;
   }
-
+  ZERO_STRUCTP(key);
   key->type = prv->type;
   switch(key->type) {
     case SSH_KEYTYPE_DSS:
@@ -466,6 +466,9 @@ ssh_public_key publickey_from_privatekey(ssh_private_key prv) {
       }
 #endif
       break;
+    default:
+    	publickey_free(key);
+    	return NULL;
   }
   key->type_c = ssh_type_to_char(prv->type);
 
@@ -715,7 +718,8 @@ ssh_string publickey_to_string(ssh_public_key key) {
   ssh_string_fill(ret, buffer_get_rest(buf), buffer_get_rest_len(buf));
 error:
   ssh_buffer_free(buf);
-  ssh_string_free(type);
+  if(type != NULL)
+  	ssh_string_free(type);
 
   return ret;
 }

src/string.c

@@ -131,8 +131,12 @@ size_t ssh_string_len(struct ssh_string_struct *s) {
  * string may not be readable with regular libc functions.
  */
 char *ssh_string_to_char(struct ssh_string_struct *s) {
-  size_t len = ntohl(s->size) + 1;
-  char *new = malloc(len);
+	size_t len;
+	char *new;
+	if(s==NULL)
+		return NULL;
+  len = ntohl(s->size) + 1;
+  new = malloc(len);
 
   if (new == NULL) {
     return NULL;