cli/insert: add --world-readable flag

In some cases (e.g. when building a publicly-visible e-mail archive)
it doesn't make any sense to restrict visibility of the message to the
current user account.

This adds a --world-readable boolean option for "notmuch insert", so
that those who want to archive their mail publicly can feed their
archiver with:

    notmuch insert --world-readable

Other local delivery agents (postfix's local, and dovecot's lda) all
default to delivery in mode 0600 rather than relying on the user's
umask, so this fix doesn't change the default.

Also, this does not override the user's umask.  if the umask is
already set tight, it will not become looser as the result of passing
--world-readable.

Signed-off-by: Daniel Kahn Gillmor <dkg@fifthhorseman.net>

1 files changed, 14 insertions, 11 deletions

diff --git a/notmuch-insert.c b/notmuch-insert.c
index 48490b51..d229c9dc 100644
--- a/notmuch-insert.c
+++ b/notmuch-insert.c
@@ -159,10 +159,10 @@ mkdir_recursive (const void *ctx, const char *path, int mode)
  * otherwise. Partial results are not cleaned up on errors.
  */
 static bool
-maildir_create_folder (const void *ctx, const char *maildir)
+maildir_create_folder (const void *ctx, const char *maildir, bool world_readable)
 {
     const char *subdirs[] = { "cur", "new", "tmp" };
-    const int mode = 0700;
+    const int mode = (world_readable ? 0755 : 0700);
     char *subdir;
     unsigned int i;
 
@@ -211,10 +211,11 @@ tempfilename (const void *ctx)
  * is not touched).
  */
 static int
-maildir_mktemp (const void *ctx, const char *maildir, char **path_out)
+maildir_mktemp (const void *ctx, const char *maildir, bool world_readable, char **path_out)
 {
     char *filename, *path;
     int fd;
+    const int mode = (world_readable ? 0644 : 0600);
 
     do {
 	filename = tempfilename (ctx);
@@ -227,7 +228,7 @@ maildir_mktemp (const void *ctx, const char *maildir, char **path_out)
 	    return -1;
 	}
 
-	fd = open (path, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0600);
+	fd = open (path, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, mode);
     } while (fd == -1 && errno == EEXIST);
 
     if (fd == -1) {
@@ -289,12 +290,12 @@ copy_fd (int fdout, int fdin)
  * the file, or NULL on errors.
  */
 static char *
-maildir_write_tmp (const void *ctx, int fdin, const char *maildir)
+maildir_write_tmp (const void *ctx, int fdin, const char *maildir, bool world_readable)
 {
     char *path;
     int fdout;
 
-    fdout = maildir_mktemp (ctx, maildir, &path);
+    fdout = maildir_mktemp (ctx, maildir, world_readable, &path);
     if (fdout < 0)
 	return NULL;
 
@@ -323,11 +324,11 @@ FAIL:
  * errors.
  */
 static char *
-maildir_write_new (const void *ctx, int fdin, const char *maildir)
+maildir_write_new (const void *ctx, int fdin, const char *maildir, bool world_readable)
 {
     char *cleanpath, *tmppath, *newpath, *newdir;
 
-    tmppath = maildir_write_tmp (ctx, fdin, maildir);
+    tmppath = maildir_write_tmp (ctx, fdin, maildir, world_readable);
     if (! tmppath)
 	return NULL;
     cleanpath = tmppath;
@@ -457,6 +458,7 @@ notmuch_insert_command (notmuch_config_t *config, int argc, char *argv[])
     bool create_folder = false;
     bool keep = false;
     bool hooks = true;
+    bool world_readable = false;
     bool synchronize_flags;
     char *maildir;
     char *newpath;
@@ -467,7 +469,8 @@ notmuch_insert_command (notmuch_config_t *config, int argc, char *argv[])
 	{ .opt_string = &folder, .name = "folder", .allow_empty = true },
 	{ .opt_bool = &create_folder, .name = "create-folder" },
 	{ .opt_bool = &keep, .name = "keep" },
-	{ .opt_bool =  &hooks, .name = "hooks" },
+	{ .opt_bool = &hooks, .name = "hooks" },
+	{ .opt_bool = &world_readable, .name = "world-readable" },
 	{ .opt_inherit = notmuch_shared_indexing_options },
 	{ .opt_inherit = notmuch_shared_options },
 	{ }
@@ -523,7 +526,7 @@ notmuch_insert_command (notmuch_config_t *config, int argc, char *argv[])
     }
 
     strip_trailing (maildir, '/');
-    if (create_folder && ! maildir_create_folder (config, maildir))
+    if (create_folder && ! maildir_create_folder (config, maildir, world_readable))
 	return EXIT_FAILURE;
 
     /* Set up our handler for SIGINT. We do not set SA_RESTART so that copying
@@ -535,7 +538,7 @@ notmuch_insert_command (notmuch_config_t *config, int argc, char *argv[])
     sigaction (SIGINT, &action, NULL);
 
     /* Write the message to the Maildir new directory. */
-    newpath = maildir_write_new (config, STDIN_FILENO, maildir);
+    newpath = maildir_write_new (config, STDIN_FILENO, maildir, world_readable);
     if (! newpath) {
 	return EXIT_FAILURE;
     }