[dovecot-cvs] dovecot/src/login client-authenticate.c,1.19,1.20 client.c,1.16,1.17 client.h,1.7,1.8

[cras at procontrol.fi]

Update of /home/cvs/dovecot/src/login
In directory danu:/tmp/cvs-serv19285/login

Modified Files:
	client-authenticate.c client.c client.h 
Log Message:
Added buffer API. Point is to hide all buffer writing behind this API which
verifies that nothing overflows. Much better than doing the same checks all
around the code, even if it is slightly slower.

Buffer reading is still mostly done directly, that isn't such a big security
risk and I can't think of a reasonable API for it anyway.



Index: client-authenticate.c
===================================================================
RCS file: /home/cvs/dovecot/src/login/client-authenticate.c,v
retrieving revision 1.19
retrieving revision 1.20
diff -u -d -r1.19 -r1.20
--- client-authenticate.c	6 Dec 2002 01:09:23 -0000	1.19
+++ client-authenticate.c	8 Dec 2002 05:23:08 -0000	1.20
@@ -2,6 +2,7 @@
 
 #include "common.h"
 #include "base64.h"
+#include "buffer.h"
 #include "ioloop.h"
 #include "istream.h"
 #include "ostream.h"
@@ -105,15 +106,17 @@
 static void client_send_auth_data(Client *client, const unsigned char *data,
 				  size_t size)
 {
-	const char *base64_data;
+	Buffer *buf;
 
 	t_push();
 
-	base64_data = base64_encode(data, size);
-	o_stream_send(client->output, "+ ", 2);
-	o_stream_send(client->output, base64_data, strlen(base64_data));
-	o_stream_send(client->output, "\r\n", 2);
+	buf = buffer_create_dynamic(data_stack_pool, size*2, (size_t)-1);
+	buffer_append(buf, "+ ", 2);
+	base64_encode(data, size, buf);
+	buffer_append(buf, "\r\n", 2);
 
+	o_stream_send(client->output, buffer_get_data(buf, NULL),
+		      buffer_get_used_size(buf));
 	o_stream_flush(client->output);
 
 	t_pop();
@@ -168,22 +171,21 @@
 			   size_t reply_data_size, void *context)
 {
 	Client *client = context;
+	const void *ptr;
+	size_t size;
 
 	if (auth_callback(request, auth_process, result,
 			  reply_data, reply_data_size, context)) {
-		auth_continue_request(request, client->plain_login,
-				      client->plain_login_len);
+                ptr = buffer_get_data(client->plain_login, &size);
+		auth_continue_request(request, ptr, size);
 
-		i_free(client->plain_login);
-                client->plain_login = NULL;
+		buffer_set_used_size(client->plain_login, 0);
 	}
 }
 
 int cmd_login(Client *client, const char *user, const char *pass)
 {
 	const char *error;
-	unsigned char *p;
-	size_t len, user_len, pass_len;
 
 	if (!client->tls && disable_plaintext_auth) {
 		client_send_tagline(client,
@@ -192,17 +194,12 @@
 	}
 
 	/* code it into user\0user\0password */
-	user_len = strlen(user);
-	pass_len = strlen(pass);
-	len = user_len + 1 + user_len + 1 + pass_len;
-
-	i_free(client->plain_login);
-	client->plain_login = p = i_malloc(len);
-	client->plain_login_len = len;
-
-	memcpy(p, user, user_len); p += user_len; *p++ = '\0';
-	memcpy(p, user, user_len); p += user_len; *p++ = '\0';
-	memcpy(p, pass, pass_len);
+	buffer_set_used_size(client->plain_login, 0);
+	buffer_append(client->plain_login, user, strlen(user));
+	buffer_append_c(client->plain_login, '\0');
+	buffer_append(client->plain_login, user, strlen(user));
+	buffer_append_c(client->plain_login, '\0');
+	buffer_append(client->plain_login, pass, strlen(pass));
 
 	client_ref(client);
 	if (auth_init_request(AUTH_METHOD_PLAIN,
@@ -237,9 +234,9 @@
 			      IO io __attr_unused__)
 {
 	Client *client = context;
+	Buffer *buf;
 	char *line;
-	ssize_t size;
-	size_t linelen;
+	size_t linelen, bufsize;
 
 	if (!client_read(client))
 		return;
@@ -253,24 +250,29 @@
 		return;
 	}
 
+	t_push();
+
 	linelen = strlen(line);
-	size = base64_decode(line, &linelen, (unsigned char *) line);
-	if (size < 0) {
+	buf = buffer_create_static_hard(data_stack_pool, linelen);
+
+	if (base64_decode(line, linelen, NULL, buf) <= 0) {
 		/* failed */
 		client_auth_abort(client, "NO Invalid base64 data");
-		return;
-	}
-
-	if (client->auth_request == NULL) {
+	} else if (client->auth_request == NULL) {
 		client_auth_abort(client, "NO Don't send unrequested data");
-		return;
+	} else {
+		auth_continue_request(client->auth_request,
+				      buffer_get_data(buf, NULL),
+				      buffer_get_used_size(buf));
 	}
 
-	auth_continue_request(client->auth_request, (unsigned char *) line,
-			      (size_t)size);
-
 	/* clear sensitive data */
-	memset(line, 0, size);
+	memset(line, 0, linelen);
+
+	bufsize = buffer_get_used_size(buf);
+	memset(buffer_free_without_data(buf), 0, bufsize);
+
+	t_pop();
 }
 
 int cmd_authenticate(Client *client, const char *method_name)

Index: client.c
===================================================================
RCS file: /home/cvs/dovecot/src/login/client.c,v
retrieving revision 1.16
retrieving revision 1.17
diff -u -d -r1.16 -r1.17
--- client.c	6 Dec 2002 01:09:23 -0000	1.16
+++ client.c	8 Dec 2002 05:23:08 -0000	1.17
@@ -1,6 +1,7 @@
 /* Copyright (C) 2002 Timo Sirainen */
 
 #include "common.h"
+#include "buffer.h"
 #include "hash.h"
 #include "ioloop.h"
 #include "istream.h"
@@ -289,7 +290,8 @@
 	client->input = i_stream_create_file(fd, default_pool, 8192, FALSE);
 	client->output = o_stream_create_file(fd, default_pool, 1024,
 					      IO_PRIORITY_DEFAULT, FALSE);
-        client->last_input = ioloop_time;
+	client->plain_login = buffer_create_dynamic(system_pool, 128, 8192);
+	client->last_input = ioloop_time;
 	hash_insert(clients, client, client);
 
 	main_ref();
@@ -334,7 +336,7 @@
 	o_stream_unref(client->output);
 
 	i_free(client->tag);
-	i_free(client->plain_login);
+	buffer_free(client->plain_login);
 	i_free(client);
 
 	main_unref();

Index: client.h
===================================================================
RCS file: /home/cvs/dovecot/src/login/client.h,v
retrieving revision 1.7
retrieving revision 1.8
diff -u -d -r1.7 -r1.8
--- client.h	6 Dec 2002 01:09:23 -0000	1.7
+++ client.h	8 Dec 2002 05:23:08 -0000	1.8
@@ -16,9 +16,7 @@
 	time_t last_input;
 	char *tag;
 
-	unsigned char *plain_login;
-	unsigned int plain_login_len;
-
+	Buffer *plain_login;
 	AuthRequest *auth_request;
 
 	unsigned int tls:1;