From 2cc93ff31f16e65c1c1f94b0044b32f6be67cbd3 Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@systemlinux.org>
Date: Sun, 11 Feb 2007 21:57:49 +0100
Subject: [PATCH] simplify lookup_user()

It's easier to just pass the name of the user to be looked up. This
fixes a memory leak btw. because u.name was strdupped and never freed.
That leak wasn't serious though as is happened in the child process.
---
 command.c   | 22 ++++++++++++----------
 error.h     |  2 +-
 user_list.c | 15 +++++++--------
 user_list.h |  2 +-
 4 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/command.c b/command.c
index 6f6fad7c..ffd660d6 100644
--- a/command.c
+++ b/command.c
@@ -793,7 +793,7 @@ int handle_connect(int fd, struct sockaddr_in *addr)
 	int numbytes, ret, argc, use_rc4 = 0;
 	char buf[4096];
 	unsigned char crypt_buf[MAXLINE];
-	struct user u;
+	struct user *u;
 	struct server_command *cmd = NULL;
 	long unsigned challenge_nr, chall_response;
 	char **argv = NULL;
@@ -825,16 +825,18 @@ int handle_connect(int fd, struct sockaddr_in *addr)
 		goto err_out;
 
 	if (numbytes < 9 || strncmp(buf, "auth rc4 ", 9))
-		u.name = para_strdup(buf + 5); /* client version < 0.2.6 */
+		p = buf + 5; /* client version < 0.2.6 */
 	else {
-		u.name = para_strdup(buf + 9); /* client version >= 0.2.6 */
+		p = buf + 9; /* client version >= 0.2.6 */
 		use_rc4 = 1;
 	}
 	PARA_DEBUG_LOG("received %s request for user %s\n",
-		use_rc4? "rc4" : "auth", u.name);
-	if ((ret = lookup_user(&u)) < 0)
+		use_rc4? "rc4" : "auth", p);
+	ret = -E_BAD_USER;
+	u = lookup_user(p);
+	if (!u)
 		goto err_out;
-	ret = para_encrypt_challenge(u.rsa, challenge_nr, crypt_buf);
+	ret = para_encrypt_challenge(u->rsa, challenge_nr, crypt_buf);
 	if (ret <= 0)
 		goto err_out;
 	numbytes = ret;
@@ -855,11 +857,11 @@ int handle_connect(int fd, struct sockaddr_in *addr)
 			|| chall_response != challenge_nr)
 		goto err_out;
 	/* auth successful. Send 'Proceed' message */
-	PARA_INFO_LOG("good auth for %s (%lu)\n", u.name, challenge_nr);
+	PARA_INFO_LOG("good auth for %s (%lu)\n", u->name, challenge_nr);
 	sprintf(buf, "%s", PROCEED_MSG);
 	if (use_rc4) {
 		init_rc4_keys();
-		ret = para_encrypt_buffer(u.rsa, rc4_buf, 2 * RC4_KEY_LEN,
+		ret = para_encrypt_buffer(u->rsa, rc4_buf, 2 * RC4_KEY_LEN,
 			(unsigned char *)buf + PROCEED_MSG_LEN + 1);
 		if (ret <= 0)
 			goto err_out;
@@ -891,7 +893,7 @@ int handle_connect(int fd, struct sockaddr_in *addr)
 	if (!(cmd = parse_cmd(command)))
 		goto err_out;
 	/* valid command, check permissions */
-	ret = check_perms(u.perms, cmd);
+	ret = check_perms(u->perms, cmd);
 	if (ret < 0)
 		goto err_out;
 	/* valid command and sufficient perms */
@@ -900,7 +902,7 @@ int handle_connect(int fd, struct sockaddr_in *addr)
 	mmd_lock();
 	mmd->num_commands++;
 	mmd_unlock();
-	PARA_NOTICE_LOG("calling com_%s() for %s@%s\n", cmd->name, u.name,
+	PARA_NOTICE_LOG("calling com_%s() for %s@%s\n", cmd->name, u->name,
 		inet_ntoa(addr->sin_addr));
 	ret = cmd->handler(fd, argc, argv);
 	if (ret >= 0) {
diff --git a/error.h b/error.h
index 34b18f19..b9709477 100644
--- a/error.h
+++ b/error.h
@@ -97,7 +97,6 @@ extern const char **para_errlist[];
 
 #define USER_LIST_ERRORS \
 	PARA_ERROR(USERLIST, "failed to open user list file"), \
-	PARA_ERROR(BAD_USER, "you don't exist. Go away."), \
 
 
 #define OSX_WRITE_ERRORS \
@@ -203,6 +202,7 @@ extern const char **para_errlist[];
 	PARA_ERROR(AUDIOD_SYNTAX, "syntax error"), \
 	PARA_ERROR(UCRED_PERM, "permission denied"), \
 	PARA_ERROR(INVALID_AUDIOD_CMD, "invalid command"), \
+	PARA_ERROR(BAD_USER, "you don't exist. Go away."), \
 
 
 #define FILTER_CHAIN_ERRORS \
diff --git a/user_list.c b/user_list.c
index b7d739c1..c6d45ca5 100644
--- a/user_list.c
+++ b/user_list.c
@@ -122,19 +122,18 @@ void init_user_list(char *user_list_file)
 /**
  * lookup user in user_list.
  *
- * \param user: must initially contain the name of the user and is filled
- * in by this function on success.
+ * \param name of the user
  *
- * \return 1 on success and < 0 on errors.
+ * \return a pointer to the corresponding user struct if the user was found,
+ *  \p NULL otherwise.
  */
-int lookup_user(struct user *user)
+struct user *lookup_user(const char *name)
 {
 	struct user *u;
 	list_for_each_entry(u, &user_list, node) {
-		if (strcmp(u->name, user->name))
+		if (strcmp(u->name, name))
 			continue;
-		*user = *u;
-		return 1;
+		return u;
 	}
-	return -E_BAD_USER;
+	return NULL;
 }
diff --git a/user_list.h b/user_list.h
index 1ee73521..ce940376 100644
--- a/user_list.h
+++ b/user_list.h
@@ -46,4 +46,4 @@ struct user {
 };
 
 void init_user_list(char *user_list_file);
-int lookup_user(struct user *user);
+struct user *lookup_user(const char *name);
-- 
2.39.5