Merge pull request #31458 from poettering/vmspawn-ptyfwd

vmspawn: implement TTY logic via ptyfwd

10 files changed, 201 insertions, 29 deletions

diff --git a/man/systemd-vmspawn.xml b/man/systemd-vmspawn.xml
index ed4dfc8bfa..d7fee0538a 100644
--- a/man/systemd-vmspawn.xml
+++ b/man/systemd-vmspawn.xml
@@ -206,14 +206,6 @@
         </varlistentry>
 
         <varlistentry>
-          <term><option>--qemu-gui</option></term>
-
-          <listitem><para>Start QEMU in graphical mode.</para>
-
-          <xi:include href="version-info.xml" xpointer="v255"/></listitem>
-        </varlistentry>
-
-        <varlistentry>
           <term><option>-n</option></term>
           <term><option>--network-tap</option></term>
 
@@ -362,6 +354,42 @@
     </refsect2>
 
     <refsect2>
+      <title>Input/Output Options</title>
+
+      <variablelist>
+        <varlistentry>
+          <term><option>--console=</option><replaceable>MODE</replaceable></term>
+
+          <listitem><para>Configures how to set up the console of the VM. Takes one of
+          <literal>interactive</literal>, <literal>read-only</literal>, <literal>native</literal>,
+          <literal>gui</literal>. Defaults to <literal>interactive</literal>. <literal>interactive</literal>
+          provides an interactive terminal interface to the VM. <literal>read-only</literal> is similar, but
+          is strictly read-only, i.e. does not accept any input from the user. <literal>native</literal> also
+          provides a TTY-based interface, but uses qemu native implementation (which means the qemu monitor
+          is available). <literal>gui</literal> shows the qemu graphical UI.</para>
+
+          <xi:include href="version-info.xml" xpointer="v256"/></listitem>
+        </varlistentry>
+
+        <varlistentry>
+          <term><option>--background=<replaceable>COLOR</replaceable></option></term>
+
+          <listitem><para>Change the terminal background color to the specified ANSI color as long as the VM
+          runs. The color specified should be an ANSI X3.64 SGR background color, i.e. strings such as
+          <literal>40</literal>, <literal>41</literal>, …, <literal>47</literal>, <literal>48;2;…</literal>,
+          <literal>48;5;…</literal>. See <ulink
+          url="https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_(Select_Graphic_Rendition)_parameters">ANSI
+          Escape Code (Wikipedia)</ulink> for details. Assign an empty string to disable any coloring. This
+          only has an effect in <option>--console=interactive</option> and
+          <option>--console=read-only</option> modes.</para>
+
+          <xi:include href="version-info.xml" xpointer="v256"/>
+          </listitem>
+        </varlistentry>
+      </variablelist>
+    </refsect2>
+
+    <refsect2>
       <title>Credentials</title>
 
       <variablelist>
diff --git a/src/basic/glyph-util.c b/src/basic/glyph-util.c
index 2cec3d82cf..b6b0f40ca6 100644
--- a/src/basic/glyph-util.c
+++ b/src/basic/glyph-util.c
@@ -77,6 +77,7 @@ const char *special_glyph_full(SpecialGlyph code, bool force_utf) {
                         [SPECIAL_GLYPH_RED_CIRCLE]              = "o",
                         [SPECIAL_GLYPH_YELLOW_CIRCLE]           = "o",
                         [SPECIAL_GLYPH_BLUE_CIRCLE]             = "o",
+                        [SPECIAL_GLYPH_GREEN_CIRCLE]            = "o",
                 },
 
                 /* UTF-8 */
@@ -143,6 +144,7 @@ const char *special_glyph_full(SpecialGlyph code, bool force_utf) {
                         [SPECIAL_GLYPH_RED_CIRCLE]              = u8"🔴",
                         [SPECIAL_GLYPH_YELLOW_CIRCLE]           = u8"🟡",
                         [SPECIAL_GLYPH_BLUE_CIRCLE]             = u8"🔵",
+                        [SPECIAL_GLYPH_GREEN_CIRCLE]            = u8"🟢",
                 },
         };
 
diff --git a/src/basic/glyph-util.h b/src/basic/glyph-util.h
index e476fefe94..2f70b187fc 100644
--- a/src/basic/glyph-util.h
+++ b/src/basic/glyph-util.h
@@ -52,6 +52,7 @@ typedef enum SpecialGlyph {
         SPECIAL_GLYPH_RED_CIRCLE,
         SPECIAL_GLYPH_YELLOW_CIRCLE,
         SPECIAL_GLYPH_BLUE_CIRCLE,
+        SPECIAL_GLYPH_GREEN_CIRCLE,
         _SPECIAL_GLYPH_MAX,
         _SPECIAL_GLYPH_INVALID = -EINVAL,
 } SpecialGlyph;
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index cd398f2461..1cb039ade4 100644
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -5991,10 +5991,12 @@ static int run(int argc, char *argv[]) {
                 _cleanup_free_ char *u = NULL;
                 (void) terminal_urlify_path(t, t, &u);
 
-                log_info("%s %sSpawning container %s on %s.%s\n"
-                         "%s %sPress %sCtrl-]%s three times within 1s to kill container.%s",
-                         special_glyph(SPECIAL_GLYPH_LIGHT_SHADE), ansi_grey(), arg_machine, u ?: t, ansi_normal(),
-                         special_glyph(SPECIAL_GLYPH_LIGHT_SHADE), ansi_grey(), ansi_highlight(), ansi_grey(), ansi_normal());
+                log_info("%s %sSpawning container %s on %s.%s",
+                         special_glyph(SPECIAL_GLYPH_LIGHT_SHADE), ansi_grey(), arg_machine, u ?: t, ansi_normal());
+
+                if (arg_console_mode == CONSOLE_INTERACTIVE)
+                        log_info("%s %sPress %sCtrl-]%s three times within 1s to kill container.%s",
+                                 special_glyph(SPECIAL_GLYPH_LIGHT_SHADE), ansi_grey(), ansi_highlight(), ansi_grey(), ansi_normal());
         }
 
         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, SIGRTMIN+18) >= 0);
diff --git a/src/run/run.c b/src/run/run.c
index ec0f4f700e..5181c18c20 100644
--- a/src/run/run.c
+++ b/src/run/run.c
@@ -1751,9 +1751,9 @@ static int start_transient_service(sd_bus *bus) {
                         return log_error_errno(r, "Failed to get event loop: %m");
 
                 if (master >= 0) {
-                        assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGWINCH, SIGTERM, SIGINT) >= 0);
-                        (void) sd_event_add_signal(c.event, NULL, SIGINT, NULL, NULL);
-                        (void) sd_event_add_signal(c.event, NULL, SIGTERM, NULL, NULL);
+                        assert_se(sigprocmask_many(SIG_BLOCK, /* old_sigset=*/ NULL, SIGWINCH) >= 0);
+
+                        (void) sd_event_set_signal_exit(c.event, true);
 
                         if (!arg_quiet)
                                 log_info("Press ^] three times within 1s to disconnect TTY.");
diff --git a/src/shared/pretty-print.c b/src/shared/pretty-print.c
index 946da5f42d..a4e5809446 100644
--- a/src/shared/pretty-print.c
+++ b/src/shared/pretty-print.c
@@ -452,7 +452,7 @@ int terminal_tint_color(double hue, char **ret) {
         else        /* otherwise pump it up */
                 s = 75;
 
-        v = MAX(30, v); /* Make sure we don't hide the color in black */
+        v = MAX(20, v); /* Make sure we don't hide the color in black */
 
         uint8_t r8, g8, b8;
         hsv_to_rgb(hue, s, v, &r8, &g8, &b8);
diff --git a/src/test/test-locale-util.c b/src/test/test-locale-util.c
index dd9a8134bf..67d9c7e65c 100644
--- a/src/test/test-locale-util.c
+++ b/src/test/test-locale-util.c
@@ -82,7 +82,7 @@ TEST(keymaps) {
 
 #define dump_glyph(x) log_info(STRINGIFY(x) ": %s", special_glyph(x))
 TEST(dump_special_glyphs) {
-        assert_cc(SPECIAL_GLYPH_BLUE_CIRCLE + 1 == _SPECIAL_GLYPH_MAX);
+        assert_cc(SPECIAL_GLYPH_GREEN_CIRCLE + 1 == _SPECIAL_GLYPH_MAX);
 
         log_info("is_locale_utf8: %s", yes_no(is_locale_utf8()));
 
@@ -130,6 +130,7 @@ TEST(dump_special_glyphs) {
         dump_glyph(SPECIAL_GLYPH_RED_CIRCLE);
         dump_glyph(SPECIAL_GLYPH_YELLOW_CIRCLE);
         dump_glyph(SPECIAL_GLYPH_BLUE_CIRCLE);
+        dump_glyph(SPECIAL_GLYPH_GREEN_CIRCLE);
 }
 
 DEFINE_TEST_MAIN(LOG_INFO);
diff --git a/src/vmspawn/vmspawn-settings.c b/src/vmspawn/vmspawn-settings.c
index cb1a463781..780df553aa 100644
--- a/src/vmspawn/vmspawn-settings.c
+++ b/src/vmspawn/vmspawn-settings.c
@@ -1,3 +1,13 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
+#include "string-table.h"
 #include "vmspawn-settings.h"
+
+static const char *const console_mode_table[_CONSOLE_MODE_MAX] = {
+        [CONSOLE_INTERACTIVE] = "interactive",
+        [CONSOLE_READ_ONLY]   = "read-only",
+        [CONSOLE_NATIVE]      = "native",
+        [CONSOLE_GUI]         = "gui",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(console_mode, ConsoleMode);
diff --git a/src/vmspawn/vmspawn-settings.h b/src/vmspawn/vmspawn-settings.h
index 60ea10e6de..fe23aa23cf 100644
--- a/src/vmspawn/vmspawn-settings.h
+++ b/src/vmspawn/vmspawn-settings.h
@@ -1,8 +1,20 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
+#include <errno.h>
 #include <stdint.h>
 
+#include "macro.h"
+
+typedef enum ConsoleMode {
+        CONSOLE_INTERACTIVE,    /* ptyfwd */
+        CONSOLE_READ_ONLY,      /* ptyfwd, but in read-only mode */
+        CONSOLE_NATIVE,         /* qemu's native TTY handling */
+        CONSOLE_GUI,            /* qemu's graphical UI */
+        _CONSOLE_MODE_MAX,
+        _CONSOLE_MODE_INVALID = -EINVAL,
+} ConsoleMode;
+
 typedef enum SettingsMask {
         SETTING_START_MODE        = UINT64_C(1) << 0,
         SETTING_BIND_MOUNTS       = UINT64_C(1) << 11,
@@ -10,3 +22,6 @@ typedef enum SettingsMask {
         SETTING_CREDENTIALS       = UINT64_C(1) << 30,
         _SETTING_FORCE_ENUM_WIDTH = UINT64_MAX
 } SettingsMask;
+
+const char *console_mode_to_string(ConsoleMode m) _const_;
+ConsoleMode console_mode_from_string(const char *s) _pure_;
diff --git a/src/vmspawn/vmspawn.c b/src/vmspawn/vmspawn.c
index 6c2d943daa..ce7f1ef2e3 100644
--- a/src/vmspawn/vmspawn.c
+++ b/src/vmspawn/vmspawn.c
@@ -46,6 +46,7 @@
 #include "path-util.h"
 #include "pretty-print.h"
 #include "process-util.h"
+#include "ptyfwd.h"
 #include "random-util.h"
 #include "rm-rf.h"
 #include "signal-util.h"
@@ -73,7 +74,7 @@ static unsigned arg_vsock_cid = VMADDR_CID_ANY;
 static int arg_tpm = -1;
 static char *arg_linux = NULL;
 static char **arg_initrds = NULL;
-static bool arg_qemu_gui = false;
+static ConsoleMode arg_console_mode = CONSOLE_INTERACTIVE;
 static NetworkStack arg_network_stack = NETWORK_STACK_NONE;
 static int arg_secure_boot = -1;
 static MachineCredentialContext arg_credentials = {};
@@ -87,6 +88,7 @@ static bool arg_runtime_directory_created = false;
 static bool arg_privileged = false;
 static char **arg_kernel_cmdline_extra = NULL;
 static char **arg_extra_drives = NULL;
+static char *arg_background = NULL;
 
 STATIC_DESTRUCTOR_REGISTER(arg_directory, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_image, freep);
@@ -101,6 +103,7 @@ STATIC_DESTRUCTOR_REGISTER(arg_runtime_mounts, runtime_mount_context_done);
 STATIC_DESTRUCTOR_REGISTER(arg_forward_journal, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_kernel_cmdline_extra, strv_freep);
 STATIC_DESTRUCTOR_REGISTER(arg_extra_drives, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_background, freep);
 
 static int help(void) {
         _cleanup_free_ char *link = NULL;
@@ -130,7 +133,6 @@ static int help(void) {
                "     --tpm=BOOL            Enable use of a virtual TPM\n"
                "     --linux=PATH          Specify the linux kernel for direct kernel boot\n"
                "     --initrd=PATH         Specify the initrd for direct kernel boot\n"
-               "     --qemu-gui            Start QEMU in graphical mode\n"
                "  -n --network-tap         Create a TAP device for networking\n"
                "     --network-user-mode   Use user mode networking\n"
                "     --secure-boot=BOOL    Enable searching for firmware supporting SecureBoot\n"
@@ -150,6 +152,9 @@ static int help(void) {
                "\n%3$sIntegration:%4$s\n"
                "     --forward-journal=FILE|DIR\n"
                "                           Forward the VM's journal to the host\n"
+               "\n%3$sInput/Output:%4$s\n"
+               "     --console=MODE        Console mode (interactive, native, gui)\n"
+               "     --background=COLOR    Set ANSI color for background\n"
                "\n%3$sCredentials:%4$s\n"
                "     --set-credential=ID:VALUE\n"
                "                           Pass a credential with literal value to the VM\n"
@@ -190,6 +195,8 @@ static int parse_argv(int argc, char *argv[]) {
                 ARG_SET_CREDENTIAL,
                 ARG_LOAD_CREDENTIAL,
                 ARG_FIRMWARE,
+                ARG_CONSOLE,
+                ARG_BACKGROUND,
         };
 
         static const struct option options[] = {
@@ -212,7 +219,8 @@ static int parse_argv(int argc, char *argv[]) {
                 { "tpm",               required_argument, NULL, ARG_TPM               },
                 { "linux",             required_argument, NULL, ARG_LINUX             },
                 { "initrd",            required_argument, NULL, ARG_INITRD            },
-                { "qemu-gui",          no_argument,       NULL, ARG_QEMU_GUI          },
+                { "console",           required_argument, NULL, ARG_CONSOLE           },
+                { "qemu-gui",          no_argument,       NULL, ARG_QEMU_GUI          }, /* compat option */
                 { "network-tap",       no_argument,       NULL, 'n'                   },
                 { "network-user-mode", no_argument,       NULL, ARG_NETWORK_USER_MODE },
                 { "bind",              required_argument, NULL, ARG_BIND              },
@@ -224,6 +232,7 @@ static int parse_argv(int argc, char *argv[]) {
                 { "set-credential",    required_argument, NULL, ARG_SET_CREDENTIAL    },
                 { "load-credential",   required_argument, NULL, ARG_LOAD_CREDENTIAL   },
                 { "firmware",          required_argument, NULL, ARG_FIRMWARE          },
+                { "background",        required_argument, NULL, ARG_BACKGROUND        },
                 {}
         };
 
@@ -344,8 +353,15 @@ static int parse_argv(int argc, char *argv[]) {
                         break;
                 }
 
+                case ARG_CONSOLE:
+                        arg_console_mode = console_mode_from_string(optarg);
+                        if (arg_console_mode < 0)
+                                return log_error_errno(arg_console_mode, "Failed to parse specified console mode: %s", optarg);
+
+                        break;
+
                 case ARG_QEMU_GUI:
-                        arg_qemu_gui = true;
+                        arg_console_mode = CONSOLE_GUI;
                         break;
 
                 case 'n':
@@ -438,6 +454,12 @@ static int parse_argv(int argc, char *argv[]) {
 
                         break;
 
+                case ARG_BACKGROUND:
+                        r = free_and_strdup_warn(&arg_background, optarg);
+                        if (r < 0)
+                                return r;
+                        break;
+
                 case '?':
                         return -EINVAL;
 
@@ -1030,6 +1052,25 @@ static int merge_initrds(char **ret) {
         return 0;
 }
 
+static void set_window_title(PTYForward *f) {
+        _cleanup_free_ char *hn = NULL, *dot = NULL;
+
+        assert(f);
+
+        (void) gethostname_strict(&hn);
+
+        if (emoji_enabled())
+                dot = strjoin(special_glyph(SPECIAL_GLYPH_GREEN_CIRCLE), " ");
+
+        if (hn)
+                (void) pty_forward_set_titlef(f, "%sVirtual Machine %s on %s", strempty(dot), arg_machine, hn);
+        else
+                (void) pty_forward_set_titlef(f, "%sVirtual Machine %s", strempty(dot), arg_machine);
+
+        if (dot)
+                (void) pty_forward_set_title_prefix(f, dot);
+}
+
 static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
         _cleanup_(ovmf_config_freep) OvmfConfig *ovmf_config = NULL;
         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
@@ -1222,12 +1263,54 @@ static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
         if (r < 0)
                 return log_oom();
 
-        if (arg_qemu_gui)
+        _cleanup_close_ int master = -EBADF;
+        PTYForwardFlags ptyfwd_flags = 0;
+        switch (arg_console_mode) {
+
+        case CONSOLE_READ_ONLY:
+                ptyfwd_flags |= PTY_FORWARD_READ_ONLY;
+
+                _fallthrough_;
+
+        case CONSOLE_INTERACTIVE:  {
+                _cleanup_free_ char *pty_path = NULL;
+
+                master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK);
+                if (master < 0)
+                        return log_error_errno(errno, "Failed to acquire pseudo tty: %m");
+
+                r = ptsname_malloc(master, &pty_path);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to determine tty name: %m");
+
+                if (unlockpt(master) < 0)
+                        return log_error_errno(errno, "Failed to unlock tty: %m");
+
+                if (strv_extend_many(
+                                &cmdline,
+                                "-nographic",
+                                "-nodefaults",
+                                "-chardev") < 0)
+                        return log_oom();
+
+                if (strv_extendf(&cmdline,
+                                 "serial,id=console,path=%s", pty_path) < 0)
+                        return log_oom();
+
+                r = strv_extend_many(
+                                &cmdline,
+                                "-serial", "chardev:console");
+                break;
+        }
+
+        case CONSOLE_GUI:
                 r = strv_extend_many(
                                 &cmdline,
                                 "-vga",
                                 "virtio");
-        else
+                break;
+
+        case CONSOLE_NATIVE:
                 r = strv_extend_many(
                                 &cmdline,
                                 "-nographic",
@@ -1235,6 +1318,11 @@ static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
                                 "-chardev", "stdio,mux=on,id=console,signal=off",
                                 "-serial", "chardev:console",
                                 "-mon", "console");
+                break;
+
+        default:
+                assert_not_reached();
+        }
         if (r < 0)
                 return log_oom();
 
@@ -1583,7 +1671,7 @@ static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
                 log_debug("Executing: %s", joined);
         }
 
-        assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD) >= 0);
+        assert_se(sigprocmask_many(SIG_BLOCK, /* old_sigset=*/ NULL, SIGCHLD, SIGWINCH) >= 0);
 
         _cleanup_(sd_event_source_unrefp) sd_event_source *notify_event_source = NULL;
         _cleanup_(sd_event_unrefp) sd_event *event = NULL;
@@ -1635,6 +1723,26 @@ static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
         /* Exit when the child exits */
         (void) event_add_child_pidref(event, NULL, &child_pidref, WEXITED, on_child_exit, NULL);
 
+        _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
+        if (master >= 0) {
+                r = pty_forward_new(event, master, ptyfwd_flags, &forward);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to create PTY forwarder: %m");
+
+                if (!arg_background) {
+                        _cleanup_free_ char *bg = NULL;
+
+                        r = terminal_tint_color(130 /* green */, &bg);
+                        if (r < 0)
+                                log_debug_errno(r, "Failed to determine terminal background color, not tinting.");
+                        else
+                                (void) pty_forward_set_background_color(forward, bg);
+                } else if (!isempty(arg_background))
+                        (void) pty_forward_set_background_color(forward, arg_background);
+
+                set_window_title(forward);
+        }
+
         r = sd_event_loop(event);
         if (r < 0)
                 return log_error_errno(r, "Failed to run event loop: %m");
@@ -1740,15 +1848,20 @@ static int run(int argc, char *argv[]) {
         if (r < 0)
                 return r;
 
-        if (!arg_quiet) {
+        if (!arg_quiet && arg_console_mode != CONSOLE_GUI) {
                 _cleanup_free_ char *u = NULL;
                 const char *vm_path = arg_image ?: arg_directory;
                 (void) terminal_urlify_path(vm_path, vm_path, &u);
 
-                log_info("%s %sSpawning VM %s on %s.%s\n"
-                         "%s %sPress %sCtrl-a x%s to kill VM.%s",
-                         special_glyph(SPECIAL_GLYPH_LIGHT_SHADE), ansi_grey(), arg_machine, u ?: vm_path, ansi_normal(),
-                         special_glyph(SPECIAL_GLYPH_LIGHT_SHADE), ansi_grey(), ansi_highlight(), ansi_grey(), ansi_normal());
+                log_info("%s %sSpawning VM %s on %s.%s",
+                         special_glyph(SPECIAL_GLYPH_LIGHT_SHADE), ansi_grey(), arg_machine, u ?: vm_path, ansi_normal());
+
+                if (arg_console_mode == CONSOLE_INTERACTIVE)
+                        log_info("%s %sPress %sCtrl-]%s three times within 1s to kill VM.%s",
+                                 special_glyph(SPECIAL_GLYPH_LIGHT_SHADE), ansi_grey(), ansi_highlight(), ansi_grey(), ansi_normal());
+                else if (arg_console_mode == CONSOLE_NATIVE)
+                        log_info("%s %sPress %sCtrl-a x%s to kill VM.%s",
+                                 special_glyph(SPECIAL_GLYPH_LIGHT_SHADE), ansi_grey(), ansi_highlight(), ansi_grey(), ansi_normal());
         }
 
         r = sd_listen_fds_with_names(true, &names);