[pve-devel] [PATCH v2 pve-storage] fix #6900: correctly detect PBS API tokens in storage plugin

[Robert Obkircher]

The PBS storage plugin used PVE code to detect if an API token was
entered in the username field. This lead to bad requests for some
valid PBS tokens which are not valid PVE tokens. Examples are
"root at pam!1234" and "root at pam!_-".

Relax the token pattern to allow token names and realms that start
with numbers or underscores. Also allow single character token names,
which are allowed on the backend even though they can't be created
through the PBS Web UI.

Signed-off-by: Robert Obkircher <r.obkircher at proxmox.com>
---
 src/PVE/Storage/PBSPlugin.pm | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/src/PVE/Storage/PBSPlugin.pm b/src/PVE/Storage/PBSPlugin.pm
index 5842004..b8dfa09 100644
--- a/src/PVE/Storage/PBSPlugin.pm
+++ b/src/PVE/Storage/PBSPlugin.pm
@@ -14,6 +14,7 @@ use POSIX qw(mktime strftime ENOENT);
 use POSIX::strptime;
 
 use PVE::APIClient::LWP;
+use PVE::Auth::Plugin;
 use PVE::JSONSchema qw(get_standard_option);
 use PVE::Network;
 use PVE::PBSClient;
@@ -701,6 +702,21 @@ my sub snapshot_files_encrypted {
     return $any && $all;
 }
 
+# SAFE_ID_REGEX_STR: &str = r"(?:[A-Za-z0-9_][A-Za-z0-9._\-]*)";
+my $safe_id_regex = qr/(?:[A-Za-z0-9_][A-Za-z0-9\._\-]*)/;
+
+# TOKEN_NAME_REGEX_STR: = SAFE_ID_REGEX_STR
+my $token_name_regex = $safe_id_regex;
+
+# USER_NAME_REGEX_STR: &str = r"(?:[^\s:/[:cntrl:]]+)";
+my $user_name_regex = qr/(?:[^\s:\/\p{PosixCntrl}]+)/;
+
+# USER_ID_REGEX_STR: &str = concatcp!(USER_NAME_REGEX_STR, r"@", SAFE_ID_REGEX_STR);
+my $user_id_regex = qr/${user_name_regex}\@${safe_id_regex}/;
+
+# APITOKEN_ID_REGEX_STR: &str = concatcp!(USER_ID_REGEX_STR, r"!", TOKEN_NAME_REGEX_STR);
+my $apitoken_id_regex = qr/${user_id_regex}\!${token_name_regex}/;
+
 # TODO: use a client with native rust/proxmox-backup bindings to profit from
 # API schema checks and types
 my sub pbs_api_connect {
@@ -710,8 +726,8 @@ my sub pbs_api_connect {
 
     my $user = $scfg->{username} // 'root at pam';
 
-    if (my $tokenid = PVE::AccessControl::pve_verify_tokenid($user, 1)) {
-        $params->{apitoken} = "PBSAPIToken=${tokenid}:${password}";
+    if ($user =~ qr/^${apitoken_id_regex}$/) {
+        $params->{apitoken} = "PBSAPIToken=${user}:${password}";
     } else {
         $params->{password} = $password;
         $params->{username} = $user;
-- 
2.47.3