Add key_list_raw() method to return keys as raw vectors

For the case when they contain zero bytes. In this case the
`service` and/or `username` is `NA`.

Closes #158.

DESCRIPTION

@@ -37,7 +37,7 @@ Config/Needs/website: tidyverse/tidytemplate
 Config/testthat/edition: 3
 Encoding: UTF-8
 Roxygen: list(markdown = TRUE, r6 = FALSE)
-RoxygenNote: 7.2.3
+RoxygenNote: 7.3.2
 SystemRequirements: Optional: libsecret on Linux (libsecret-1-dev on
     Debian/Ubuntu, libsecret-devel on Fedora/CentOS)
 Collate: 

NAMESPACE

@@ -13,6 +13,7 @@ export(key_delete)
 export(key_get)
 export(key_get_raw)
 export(key_list)
+export(key_list_raw)
 export(key_set)
 export(key_set_with_raw_value)
 export(key_set_with_value)

R/api.R

@@ -27,6 +27,10 @@
 #' `key_list` lists all keys of a keyring, or the keys for a certain
 #' service (if `service` is not `NULL`).
 #'
+#' `key_list_raw()` is like `key_list()` but also returns the keys as raw
+#' values. This is useful if your keys have bytes that cannot appear
+#' in R strings, e.g. a zero byte.
+#'
 #' ## Encodings
 #'
 #' On Windows, if required, an encoding can be specified using either
@@ -56,7 +60,16 @@
 #'   confidential information that was stored in the key.
 #'
 #'   `key_list` returns a list of keys, i.e. service names and usernames,
-#'   in a data frame.
+#'   in a data frame with column names `service` and `username`. If a
+#'   service or user name contains a zero byte, which is not allowed in an
+#'   R string, that entry is shown as `NA` and a warning (of class
+#'   `keyring_warn_zero_byte_keys`) is thrown.  You can use the
+#'   `key_list_raw()` function to query these keys.
+#'
+#'   `key_list_raw` is similar to `key_list` but returns service and
+#'   usernames as raw vectors. This is useful if some service or user
+#'   names) contain zero bytes. All column names: `service`, `username`,
+#'   `service_raw`, `username_raw`.
 #'
 #' @export
 #' @examples
@@ -163,6 +176,14 @@ key_list <- function(service = NULL, keyring = NULL) {
   default_backend()$list(service, keyring = keyring)
 }
 
+#' @export
+#' @rdname key_get
+
+key_list_raw <- function(service = NULL, keyring = NULL) {
+  assert_that(is_non_empty_string_or_null(service))
+  default_backend()$list_raw(service, keyring = keyring)
+}
+
 #' Operations on keyrings
 #'
 #' On most platforms `keyring` supports multiple keyrings. This includes

R/backend-class.R

@@ -24,6 +24,7 @@ abstract_method <- function() {
 #'                keyring = NULL)
 #' delete(service, username = NULL, keyring = NULL)
 #' list(service = NULL, keyring = NULL)
+#' list_raw(service = NULL, keyring = NULL)
 #' ```
 #'
 #' What these functions do:
@@ -39,6 +40,7 @@ abstract_method <- function() {
 #'   byte sequence of a raw vector.
 #' * `delete()` remotes a keyring item.
 #' * `list()` lists keyring items.
+#' * `list_raw()` lists keyring items, also as raw vectors.
 #'
 #' The arguments:
 #' * `service` String, the name of a service. This is used to find the
@@ -83,6 +85,12 @@ backend <- R6Class(
       abstract_method(),
     list = function(service = NULL, keyring = NULL)
       stop("Backend does not implement 'list'"),
+    list_raw = function(service = NULL, keyring = NULL) {
+      keys <- self$list(service, keyring)
+      keys$service_raw <- lapply(keys$service, charToRaw)
+      keys$username_raw <- lapply(keys$username, charToRaw)
+      keys
+    },
 
     print = function(...) {
       d <- self$docs()
@@ -116,6 +124,7 @@ backend <- R6Class(
         set_with_value = "set a key in the keyring",
         delete = "delete a key",
         list = "list keys in a keyring",
+        list_raw = "list keys in a keyring as raw vectors",
         has_keyring_support = "TRUE if multiple keyrings are supported"
       )
     }

R/backend-macos.R

@@ -50,6 +50,8 @@ backend_macos <- R6Class(
       b_macos_delete(self, private, service, username, keyring),
     list = function(service = NULL, keyring = NULL)
       b_macos_list(self, private, service, keyring),
+    list_raw = function(service = NULL, keyring = NULL)
+      b_macos_list_raw(self, private, service, keyring),
 
     keyring_create = function(keyring, password = NULL)
       b_macos_keyring_create(self, private, keyring, password),
@@ -143,11 +145,41 @@ b_macos_delete <- function(self, private, service, username, keyring) {
 b_macos_list <- function(self, private, service, keyring) {
   keyring <- private$keyring_file(keyring %||% private$keyring)
   res <- .Call(keyring_macos_list, utf8(keyring), utf8(service))
-  data.frame(
+  df <- data.frame(
+    service = res[[1]],
+    username = res[[2]],
+    stringsAsFactors = FALSE
+  )
+  srv_na <- anyNA(df[["service"]])
+  usr_na <- anyNA(df[["username"]])
+  if (srv_na | usr_na) {
+    cnd <- structure(
+      list(message = paste0(
+        "Some ",
+        if (srv_na) "service names ",
+        if (srv_na && usr_na) "and some ",
+        if (usr_na) "user names ",
+        "contain zero bytes. These are shown as NA. ",
+        "Use `key_list_raw()` to see them."
+      )),
+      class = "keyring_warn_zero_byte_keys"
+    )
+    warning(cnd)
+  }
+  df
+}
+
+b_macos_list_raw <- function(self, private, service, keyring) {
+  keyring <- private$keyring_file(keyring %||% private$keyring)
+  res <- .Call(keyring_macos_list, utf8(keyring), utf8(service))
+  df <- data.frame(
     service = res[[1]],
     username = res[[2]],
     stringsAsFactors = FALSE
   )
+  df[["service_raw"]] <- res[[3]]
+  df[["username_raw"]] <- res[[4]]
+  df
 }
 
 b_macos_keyring_create <- function(self, private, keyring, password) {

R/package.R

@@ -26,12 +26,12 @@
 #' the termination of and R session. Specifically, you can define a key
 #' once, and then read the key value in completely independent R sessions.
 #'
-#' - Setting a secret interactively: [key_set()]
+#' - Setting a secret interactively: [key_set()].
 #' - Setting a secret from a script, i.e. non-interactively:
-#'   [key_set_with_value()]
-#' - Reading a secret: [key_get()]
-#' - Listing secrets: [key_list()]
-#' - Deleting a secret: [key_delete()]
+#'   [key_set_with_value()].
+#' - Reading a secret: [key_get()], [key_get_raw()].
+#' - Listing secrets: [key_list()], [key_list_raw()].
+#' - Deleting a secret: [key_delete()].
 #'
 #' @section Managing keyrings:
 #'

src/keyring_macos.c

@@ -211,10 +211,33 @@ static void keyring_macos_list_item(SecKeychainItemRef item, SEXP result,
 					       /* outData = */ NULL);
 # pragma GCC diagnostic pop
   keyring_macos_handle_status("cannot list passwords", status);
-  SET_STRING_ELT(VECTOR_ELT(result, 0), idx,
-		 mkCharLen(attrs[0].data, attrs[0].length));
-  SET_STRING_ELT(VECTOR_ELT(result, 1), idx,
-		 mkCharLen(attrs[1].data, attrs[1].length));
+  SET_VECTOR_ELT(VECTOR_ELT(result, 2), idx,
+     Rf_allocVector(RAWSXP, attrs[0].length));
+  memcpy(
+    RAW(VECTOR_ELT(VECTOR_ELT(result, 2), idx)),
+    attrs[0].data,
+    attrs[0].length
+  );
+  if (memchr(attrs[0].data, '\0', attrs[0].length) == NULL) {
+    SET_STRING_ELT(VECTOR_ELT(result, 0), idx,
+      mkCharLen(attrs[0].data, attrs[0].length));
+  } else {
+    SET_STRING_ELT(VECTOR_ELT(result, 0), idx, NA_STRING);
+  }
+
+  SET_VECTOR_ELT(VECTOR_ELT(result, 3), idx,
+     Rf_allocVector(RAWSXP, attrs[1].length));
+  memcpy(
+    RAW(VECTOR_ELT(VECTOR_ELT(result, 3), idx)),
+    attrs[1].data,
+    attrs[1].length
+  );
+  if (memchr(attrs[0].data, '\0', attrs[0].length) == NULL) {
+    SET_STRING_ELT(VECTOR_ELT(result, 1), idx,
+      mkCharLen(attrs[1].data, attrs[1].length));
+  } else {
+    SET_STRING_ELT(VECTOR_ELT(result, 1), idx, NA_STRING);
+  }
 # pragma GCC diagnostic push
 # pragma GCC diagnostic ignored "-Wdeprecated-declarations"
   SecKeychainItemFreeContent(&attrList, NULL);
@@ -287,9 +310,11 @@ SEXP keyring_macos_list(SEXP keyring, SEXP service) {
   CFArrayRef resArray = keyring_macos_list_get(ckeyring, cservice);
   CFIndex i, num = CFArrayGetCount(resArray);
   SEXP result;
-  PROTECT(result = allocVector(VECSXP, 2));
+  PROTECT(result = allocVector(VECSXP, 4));
   SET_VECTOR_ELT(result, 0, allocVector(STRSXP, num));
   SET_VECTOR_ELT(result, 1, allocVector(STRSXP, num));
+  SET_VECTOR_ELT(result, 2, allocVector(VECSXP, num));
+  SET_VECTOR_ELT(result, 3, allocVector(VECSXP, num));
   for (i = 0; i < num; i++) {
     SecKeychainItemRef item =
       (SecKeychainItemRef) CFArrayGetValueAtIndex(resArray, i);

tests/testthat/_snaps/macos.md

@@ -0,0 +1,54 @@
+# zero bytes in keys
+
+    Code
+      b_macos_list(NULL, list(keyring_file = function(...) NULL))
+    Condition
+      Warning in `b_macos_list()`:
+      Some service names contain zero bytes. These are shown as NA. Use `key_list_raw()` to see them.
+    Output
+        service username
+      1     foo      bar
+      2    <NA>      baz
+    Code
+      b_macos_list_raw(NULL, list(keyring_file = function(...) NULL))
+    Output
+        service username    service_raw username_raw
+      1     foo      bar     66, 6f, 6f   62, 61, 72
+      2    <NA>      baz 03, 02, 01, 00   62, 61, 7a
+
+---
+
+    Code
+      b_macos_list(NULL, list(keyring_file = function(...) NULL))
+    Condition
+      Warning in `b_macos_list()`:
+      Some service names and some user names contain zero bytes. These are shown as NA. Use `key_list_raw()` to see them.
+    Output
+        service username
+      1     foo      bar
+      2    <NA>     <NA>
+    Code
+      b_macos_list_raw(NULL, list(keyring_file = function(...) NULL))
+    Output
+        service username    service_raw       username_raw
+      1     foo      bar     66, 6f, 6f         62, 61, 72
+      2    <NA>     <NA> 03, 02, 01, 00 01, 02, 00, 01, 02
+
+---
+
+    Code
+      b_macos_list(NULL, list(keyring_file = function(...) NULL))
+    Condition
+      Warning in `b_macos_list()`:
+      Some user names contain zero bytes. These are shown as NA. Use `key_list_raw()` to see them.
+    Output
+        service username
+      1     foo      bar
+      2     baz     <NA>
+    Code
+      b_macos_list_raw(NULL, list(keyring_file = function(...) NULL))
+    Output
+        service username service_raw   username_raw
+      1     foo      bar  66, 6f, 6f     62, 61, 72
+      2     baz     <NA>  62, 61, 7a 03, 02, 01, 00
+