and clean up it

diff --git a/lock.c b/lock.c
index 219f199f32ba16812654c6618c30c5d5063c4955..0b04ef29a10946d479fe6447940f06c6bd31f1e6 100644 (file)
--- a/lock.c
+++ b/lock.c
@@ -12,6 +12,26 @@
 
 #define LOCK_MAX_TRIES 30
 
+gid_t rgid, egid, sgid;
+
+void
+save_gids(void)
+{
+       getresgid(&rgid, &egid, &sgid); 
+}
+
+static void
+drop_gid(void)
+{
+       setresgid(rgid, rgid, egid);
+}
+
+static void
+raise_gid(void)
+{
+       setresgid(rgid, sgid, sgid);
+}
+
 static void
 random_sleep(unsigned int about, unsigned int offset)
 {
@@ -43,7 +63,7 @@ dot_lock(char* path)
        int fd;
        int res = -1;
        char* lockfile = cat(path, ".lock");
-       
+
        for (i = 0; i < LOCK_MAX_TRIES; i++){
                if ((fd = open(lockfile, O_WRONLY | O_EXCL | O_CREAT, 0)) 
                        >= 0) {
@@ -69,13 +89,14 @@ dot_unlock(char* path)
 {
        char* lockfile = cat(path, ".lock");
 
+       raise_gid();
        unlink(lockfile);
-
+       drop_gid();
        free(lockfile);
 }
 
-int
-open_mailbox(char* path, int use_default_mailbox)
+static int
+do_open_mailbox(char* path, int is_default_mailbox)
 {
        int fd;
 
@@ -86,36 +107,17 @@ open_mailbox(char* path, int use_default_mailbox)
        /* if OK, try to open the file:
                either we are saving to default mailbox (no problem here)
                or we are saving somewhere else (no need to be privileged)
-       */      
-       if (use_default_mailbox){
-               /* get our preciousss out of pocket */
-               gid_t ruid, euid, suid;
-               getresgid(&ruid, &euid, &suid);
-               setresgid(ruid, suid, suid);
-
-               /* we are not going to create default mailbox */
-               fd = open(path, O_RDWR);
-               if (fd < 0){
-                       dot_unlock(path);
-                       return -1;
-               }
-
-               /* hide it again */
-               setresgid(ruid, ruid, suid);
-       } else {
-               fd = open(path, O_RDWR);
-               if (fd < 0 && errno == ENOENT){
-                       fd = open(path, O_RDWR | O_CREAT | O_EXCL,
-                               S_IRUSR | S_IWUSR);
-                       if (fd < 0){
-                               dot_unlock(path);
-                               return -1;      
-                       }
-
-               } else if (fd < 0){
-                       dot_unlock(path);
-                       return -1;
-               }       
+       */
+       int perms = S_IRUSR | S_IWUSR;
+       if (is_default_mailbox)
+               perms |=  (S_IRGRP | S_IWGRP);
+
+       mode_t oldmask = umask(0);
+       fd = open(path, O_RDWR | O_CREAT, perms);
+       umask(oldmask);
+       if (fd < 0){
+               dot_unlock(path);
+               return -1;
        }       
 
        /* fcntl then */
@@ -133,8 +135,8 @@ open_mailbox(char* path, int use_default_mailbox)
        return fd; 
 }
 
-void
-close_mailbox(int fd, char* path)
+static void
+do_close_mailbox(int fd, char* path)
 {
        struct flock mb_lock;
        memset(&mb_lock, 0, sizeof(struct flock));
@@ -144,23 +146,47 @@ close_mailbox(int fd, char* path)
        dot_unlock(path);
 }
 
+void
+close_mailbox(int fd, char* path, int is_default_mailbox)
+{
+       if (is_default_mailbox)
+               raise_gid();
+       do_close_mailbox(fd, path);
+       if (is_default_mailbox)
+               drop_gid();
+}
+
+int
+open_mailbox(char* path, int is_default_mailbox)
+{
+       int fd;
+
+       if (is_default_mailbox)
+               raise_gid();
+       fd = do_open_mailbox(path, is_default_mailbox);
+       if (is_default_mailbox)
+               drop_gid();
+
+       return fd;
+}
+
 int
 main(int argc, char** argv)
 {
        /* FIXME: move somewhere */
        int fd;
-       gid_t ruid, euid, suid;
-       if (argc < 2)
+       if (argc < 3)
                return 1;
-       char* mb = argv[1]; 
-       getresgid(&ruid, &euid, &suid);
-       setresgid(ruid, ruid, euid);
-       fd = open_mailbox(mb, 0);
+       char* mb = argv[1];
+       int is_default_mailbox = atoi(argv[2]);
+       save_gids();
+       drop_gid(); 
+       fd = open_mailbox(mb, is_default_mailbox);
        printf("%d\n", fd); 
        if (fd < 0)
                return 1;       
 
-       close_mailbox(fd, mb);
+       close_mailbox(fd, mb, is_default_mailbox);
 
        return 0;
 }