From 77d74b404ee9cd6dd0c41e15789873ff287bca06 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@musicpd.org>
Date: Thu, 14 Oct 2021 14:25:20 +0200
Subject: [PATCH] Permission: add option "host_permissions"
Closes https://github.com/MusicPlayerDaemon/MPD/issues/1115
---
NEWS | 1 +
doc/user.rst | 5 +++++
src/Permission.cxx | 44 +++++++++++++++++++++++++++++++++++++---
src/Permission.hxx | 7 +++++++
src/client/Listener.cxx | 8 ++++++--
src/config/Option.hxx | 1 +
src/config/Templates.cxx | 1 +
src/net/ToString.cxx | 29 ++++++++++++++++++++++++++
src/net/ToString.hxx | 8 ++++++++
9 files changed, 99 insertions(+), 5 deletions(-)
diff --git a/NEWS b/NEWS
index b85d12751..214e54406 100644
--- a/NEWS
+++ b/NEWS
@@ -25,6 +25,7 @@ ver 0.23 (not yet released)
* tags
- new tags "ComposerSort", "Ensemble", "Movement", "MovementNumber", and "Location"
* split permission "player" from "control"
+* add option "host_permissions"
* new build-time dependency: libfmt
ver 0.22.11 (2021/08/24)
diff --git a/doc/user.rst b/doc/user.rst
index 4b26ff192..1416b7be8 100644
--- a/doc/user.rst
+++ b/doc/user.rst
@@ -650,6 +650,9 @@ By default, all clients are unauthenticated and have a full set of permissions.
:code:`local_permissions` may be used to assign other permissions to clients connecting on a local socket.
+:code:`host_permissions` may be used to assign permissions to clients
+with a certain IP address.
+
:code:`password` allows the client to send a password to gain other permissions. This option may be specified multiple times with different passwords.
Note that the :code:`password` option is not secure: passwords are sent in clear-text over the connection, and the client cannot verify the server's identity.
@@ -659,6 +662,8 @@ Example:
.. code-block:: none
default_permissions "read"
+ host_permissions "192.168.0.100 read,add,control,admin"
+ host_permissions "2003:1234:4567::1 read,add,control,admin"
password "the_password@read,add,control"
password "the_admin_password@read,add,control,admin"
diff --git a/src/Permission.cxx b/src/Permission.cxx
index a76feb195..861f0e1a2 100644
--- a/src/Permission.cxx
+++ b/src/Permission.cxx
@@ -22,6 +22,9 @@
#include "config/Param.hxx"
#include "config/Data.hxx"
#include "config/Option.hxx"
+#include "net/AddressInfo.hxx"
+#include "net/Resolver.hxx"
+#include "net/ToString.hxx"
#include "util/IterableSplitString.hxx"
#include "util/RuntimeError.hxx"
#include "util/StringView.hxx"
@@ -55,6 +58,10 @@ static unsigned permission_default;
static unsigned local_permissions;
#endif
+#ifdef HAVE_TCP
+static std::map<std::string, unsigned> host_passwords;
+#endif
+
static unsigned
ParsePermission(StringView s)
{
@@ -66,10 +73,9 @@ ParsePermission(StringView s)
int(s.size), s.data);
}
-static unsigned parsePermissions(const char *string)
+static unsigned
+parsePermissions(std::string_view string)
{
- assert(string != nullptr);
-
unsigned permission = 0;
for (const auto i : IterableSplitString(string, PERMISSION_SEPARATOR))
@@ -120,8 +126,40 @@ initPermissions(const ConfigData &config)
: permission_default;
});
#endif
+
+#ifdef HAVE_TCP
+ for (const auto ¶m : config.GetParamList(ConfigOption::HOST_PERMISSIONS)) {
+ permission_default = 0;
+
+ param.With([](StringView value){
+ auto [host_sv, permissions_s] = value.Split(' ');
+ unsigned permissions = parsePermissions(permissions_s);
+
+ const std::string host_s{host_sv};
+
+ for (const auto &i : Resolve(host_s.c_str(), 0,
+ AI_PASSIVE, SOCK_STREAM))
+ host_passwords.emplace(HostToString(i),
+ permissions);
+ });
+ }
+#endif
}
+#ifdef HAVE_TCP
+
+int
+GetPermissionsFromAddress(SocketAddress address) noexcept
+{
+ if (auto i = host_passwords.find(HostToString(address));
+ i != host_passwords.end())
+ return i->second;
+
+ return -1;
+}
+
+#endif
+
int
getPermissionFromPassword(const char *password, unsigned *permission) noexcept
{
diff --git a/src/Permission.hxx b/src/Permission.hxx
index 0161fc8f1..2d9dfb9ae 100644
--- a/src/Permission.hxx
+++ b/src/Permission.hxx
@@ -23,6 +23,7 @@
#include "config.h"
struct ConfigData;
+class SocketAddress;
static constexpr unsigned PERMISSION_NONE = 0;
static constexpr unsigned PERMISSION_READ = 1;
@@ -45,6 +46,12 @@ unsigned
GetLocalPermissions() noexcept;
#endif
+#ifdef HAVE_TCP
+[[gnu::pure]]
+int
+GetPermissionsFromAddress(SocketAddress address) noexcept;
+#endif
+
void
initPermissions(const ConfigData &config);
diff --git a/src/client/Listener.cxx b/src/client/Listener.cxx
index b71055b86..4a15bf799 100644
--- a/src/client/Listener.cxx
+++ b/src/client/Listener.cxx
@@ -32,8 +32,12 @@ GetPermissions(SocketAddress address, int uid) noexcept
#ifdef HAVE_UN
if (address.GetFamily() == AF_LOCAL)
return GetLocalPermissions();
-#else
- (void)address;
+#endif
+
+#ifdef HAVE_TCP
+ if (int permissions = GetPermissionsFromAddress(address);
+ permissions >= 0)
+ return permissions;
#endif
return getDefaultPermissions();
diff --git a/src/config/Option.hxx b/src/config/Option.hxx
index e05c48fd1..a62fc691e 100644
--- a/src/config/Option.hxx
+++ b/src/config/Option.hxx
@@ -48,6 +48,7 @@ enum class ConfigOption {
ZEROCONF_NAME,
ZEROCONF_ENABLED,
PASSWORD,
+ HOST_PERMISSIONS,
LOCAL_PERMISSIONS,
DEFAULT_PERMS,
AUDIO_OUTPUT_FORMAT,
diff --git a/src/config/Templates.cxx b/src/config/Templates.cxx
index 5f3a34ddd..f3789a0e2 100644
--- a/src/config/Templates.cxx
+++ b/src/config/Templates.cxx
@@ -44,6 +44,7 @@ const ConfigTemplate config_param_templates[] = {
{ "zeroconf_name" },
{ "zeroconf_enabled" },
{ "password", true },
+ { "host_permissions", true },
{ "local_permissions" },
{ "default_permissions" },
{ "audio_output_format" },
diff --git a/src/net/ToString.cxx b/src/net/ToString.cxx
index 8d595cd3d..b9935ea92 100644
--- a/src/net/ToString.cxx
+++ b/src/net/ToString.cxx
@@ -116,3 +116,32 @@ ToString(SocketAddress address) noexcept
result.append(serv);
return result;
}
+
+std::string
+HostToString(SocketAddress address) noexcept
+{
+ if (address.IsNull())
+ return "null";
+
+#ifdef HAVE_UN
+ if (address.GetFamily() == AF_LOCAL)
+ /* return path of local socket */
+ return LocalAddressToString(address.CastTo<struct sockaddr_un>(),
+ address.GetSize());
+#endif
+
+#if defined(HAVE_IPV6) && defined(IN6_IS_ADDR_V4MAPPED)
+ IPv4Address ipv4_buffer;
+ if (address.IsV4Mapped())
+ address = ipv4_buffer = address.UnmapV4();
+#endif
+
+ char host[NI_MAXHOST], serv[NI_MAXSERV];
+ int ret = getnameinfo(address.GetAddress(), address.GetSize(),
+ host, sizeof(host), serv, sizeof(serv),
+ NI_NUMERICHOST|NI_NUMERICSERV);
+ if (ret != 0)
+ return "unknown";
+
+ return host;
+}
diff --git a/src/net/ToString.hxx b/src/net/ToString.hxx
index 78ed421c3..3f67785c9 100644
--- a/src/net/ToString.hxx
+++ b/src/net/ToString.hxx
@@ -42,4 +42,12 @@ class SocketAddress;
std::string
ToString(SocketAddress address) noexcept;
+/**
+ * Generates the string representation of a #SocketAddress into the
+ * specified buffer, without the port number.
+ */
+[[gnu::pure]]
+std::string
+HostToString(SocketAddress address) noexcept;
+
#endif