console-server: Add PTY support for testing purposes
Different TTY device types have different configuration options. The
existing code kinda smooshes the differences between UARTs and VUARTs
together. PTYs do not require the configuration applicable to either
UARTs or VUARTs. Given this, separate out and be explict about the
concepts and configuration required for all three types.
This in turn, with some further patches, allows testing of obmc-console
using `socat`:
https://amboar.github.io/notes/2023/05/02/testing-obmc-console-with-socat.html
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: I3c1ce610132fce8ef6b5324ed3b4e0c86395e433
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 985cbfc..6e1537d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,3 +16,13 @@
- Security
## [Unreleased]
+
+### Added
+
+1. console-server: Add PTY support for testing purposes
+
+### Changed
+
+1. The `xyz.openbmc_project.console` interface is only published if the
+ underlying TTY device is a UART and not a VUART nor PTY (where baud is not
+ applicable)
diff --git a/console-dbus.c b/console-dbus.c
index 3b24061..d1dd674 100644
--- a/console-dbus.c
+++ b/console-dbus.c
@@ -14,6 +14,7 @@
* limitations under the License.
*/
+#include <assert.h>
#include <errno.h>
#include <err.h>
@@ -42,7 +43,7 @@
continue;
}
- rc = handler->baudrate(handler, console->tty_baud);
+ rc = handler->baudrate(handler, console->tty.uart.baud);
if (rc) {
warnx("Can't set terminal baudrate for handler %s",
handler->name);
@@ -75,7 +76,8 @@
return sd_bus_reply_method_return(msg, "x", -EINVAL);
}
- console->tty_baud = speed;
+ assert(console->tty.type == TTY_DEVICE_UART);
+ console->tty.uart.baud = speed;
tty_change_baudrate(console);
return sd_bus_reply_method_return(msg, "x", r);
@@ -92,9 +94,10 @@
uint32_t baudrate;
int r;
- baudrate = parse_baud_to_int(console->tty_baud);
+ assert(console->tty.type == TTY_DEVICE_UART);
+ baudrate = parse_baud_to_int(console->tty.uart.baud);
if (!baudrate) {
- warnx("Invalid baud rate: '%d'", console->tty_baud);
+ warnx("Invalid baud rate: '%d'", console->tty.uart.baud);
}
r = sd_bus_message_append(reply, "u", baudrate);
@@ -162,12 +165,15 @@
return;
}
- /* Register tty interface */
- r = sd_bus_add_object_vtable(console->bus, NULL, obj_name, TTY_INTF,
- console_tty_vtable, console);
- if (r < 0) {
- warnx("Failed to issue method call: %s", strerror(-r));
- return;
+ if (console->tty.type == TTY_DEVICE_UART) {
+ /* Register tty interface */
+ r = sd_bus_add_object_vtable(console->bus, NULL, obj_name,
+ TTY_INTF, console_tty_vtable,
+ console);
+ if (r < 0) {
+ warnx("Failed to issue method call: %s", strerror(-r));
+ return;
+ }
}
/* Register access interface */
diff --git a/console-server.c b/console-server.c
index 3b94451..fd97a6f 100644
--- a/console-server.c
+++ b/console-server.c
@@ -39,6 +39,8 @@
#include "console-server.h"
+#define DEV_PTS_PATH "/dev/pts"
+
/* size of the shared backlog ringbuffer */
const size_t buffer_size = 128ul * 1024ul;
@@ -56,33 +58,64 @@
progname);
}
-/* populates tty_dev and tty_sysfs_devnode, using the tty kernel name */
+/* populates console->tty.dev and console->tty.sysfs_devnode, using the tty kernel name */
static int tty_find_device(struct console *console)
{
char *tty_class_device_link = NULL;
char *tty_path_input_real = NULL;
char *tty_device_tty_dir = NULL;
+ char *tty_vuart_lpc_addr = NULL;
char *tty_device_reldir = NULL;
- char *tty_path_input = NULL;
+ char *tty_sysfs_devnode = NULL;
char *tty_kname_real = NULL;
+ char *tty_path_input = NULL;
int rc;
- /* udev may rename the tty name with a symbol link, try to resolve */
- rc = asprintf(&tty_path_input, "/dev/%s", console->tty_kname);
- if (rc < 0) {
- return -1;
+ console->tty.type = TTY_DEVICE_UNDEFINED;
+
+ assert(console->tty.kname);
+ if (!strlen(console->tty.kname)) {
+ warnx("TTY kname must not be empty");
+ rc = -1;
+ goto out_free;
}
+ if (console->tty.kname[0] == '/') {
+ tty_path_input = strdup(console->tty.kname);
+ if (!tty_path_input) {
+ rc = -1;
+ goto out_free;
+ }
+ } else {
+ rc = asprintf(&tty_path_input, "/dev/%s", console->tty.kname);
+ if (rc < 0) {
+ goto out_free;
+ }
+ }
+
+ /* udev may rename the tty name with a symbol link, try to resolve */
tty_path_input_real = realpath(tty_path_input, NULL);
if (!tty_path_input_real) {
- warn("Can't find realpath for /dev/%s", console->tty_kname);
+ warn("Can't find realpath for %s", tty_path_input);
rc = -1;
goto out_free;
}
+ /*
+ * Allow hooking obmc-console-server up to PTYs for testing
+ *
+ * https://amboar.github.io/notes/2023/05/02/testing-obmc-console-with-socat.html
+ */
+ if (!strncmp(DEV_PTS_PATH, tty_path_input_real, strlen(DEV_PTS_PATH))) {
+ console->tty.type = TTY_DEVICE_PTY;
+ console->tty.dev = strdup(console->tty.kname);
+ rc = console->tty.dev ? 0 : -1;
+ goto out_free;
+ }
+
tty_kname_real = basename(tty_path_input_real);
if (!tty_kname_real) {
- warn("Can't find real name for /dev/%s", console->tty_kname);
+ warn("Can't find real name for %s", console->tty.kname);
rc = -1;
goto out_free;
}
@@ -105,19 +138,29 @@
goto out_free;
}
- console->tty_sysfs_devnode = realpath(tty_device_reldir, NULL);
- if (!console->tty_sysfs_devnode) {
+ tty_sysfs_devnode = realpath(tty_device_reldir, NULL);
+ if (!tty_sysfs_devnode) {
warn("Can't find parent device for %s", tty_kname_real);
}
- rc = asprintf(&console->tty_dev, "/dev/%s", tty_kname_real);
+ rc = asprintf(&console->tty.dev, "/dev/%s", tty_kname_real);
if (rc < 0) {
goto out_free;
}
+ /* Arbitrarily pick an attribute to differentiate UART vs VUART */
+ rc = asprintf(&tty_vuart_lpc_addr, "%s/lpc_addr", tty_sysfs_devnode);
+ if (rc < 0) {
+ goto out_free;
+ }
+
+ rc = access(tty_vuart_lpc_addr, F_OK);
+ console->tty.type = (!rc) ? TTY_DEVICE_VUART : TTY_DEVICE_UART;
+
rc = 0;
out_free:
+ free(tty_vuart_lpc_addr);
free(tty_class_device_link);
free(tty_device_tty_dir);
free(tty_device_reldir);
@@ -133,7 +176,13 @@
FILE *fp;
int rc;
- rc = asprintf(&path, "%s/%s", console->tty_sysfs_devnode, name);
+ assert(console->tty.type == TTY_DEVICE_VUART);
+
+ if (!console->tty.vuart.sysfs_devnode) {
+ return -1;
+ }
+
+ rc = asprintf(&path, "%s/%s", console->tty.vuart.sysfs_devnode, name);
if (rc < 0) {
return -1;
}
@@ -141,7 +190,7 @@
fp = fopen(path, "w");
if (!fp) {
warn("Can't access attribute %s on device %s", name,
- console->tty_kname);
+ console->tty.kname);
rc = -1;
goto out_free;
}
@@ -150,7 +199,7 @@
rc = fprintf(fp, "0x%x", value);
if (rc < 0) {
warn("Error writing to %s attribute of device %s", name,
- console->tty_kname);
+ console->tty.kname);
}
fclose(fp);
@@ -167,15 +216,15 @@
struct termios termios;
int rc;
- rc = tcgetattr(console->tty_fd, &termios);
+ rc = tcgetattr(console->tty.fd, &termios);
if (rc) {
warn("Can't read tty termios");
return;
}
- if (console->tty_baud) {
- if (cfsetspeed(&termios, console->tty_baud) < 0) {
- warn("Couldn't set speeds for %s", console->tty_kname);
+ if (console->tty.type == TTY_DEVICE_UART && console->tty.uart.baud) {
+ if (cfsetspeed(&termios, console->tty.uart.baud) < 0) {
+ warn("Couldn't set speeds for %s", console->tty.kname);
}
}
@@ -184,51 +233,57 @@
*/
cfmakeraw(&termios);
- rc = tcsetattr(console->tty_fd, TCSANOW, &termios);
+ rc = tcsetattr(console->tty.fd, TCSANOW, &termios);
if (rc) {
- warn("Can't set terminal options for %s", console->tty_kname);
+ warn("Can't set terminal options for %s", console->tty.kname);
}
}
/**
* Open and initialise the serial device
*/
-static int tty_init_io(struct console *console)
+static void tty_init_vuart_io(struct console *console)
{
- if (console->tty_sirq) {
- tty_set_sysfs_attr(console, "sirq", console->tty_sirq);
- }
- if (console->tty_lpc_addr) {
- tty_set_sysfs_attr(console, "lpc_address",
- console->tty_lpc_addr);
+ assert(console->tty.type == TTY_DEVICE_VUART);
+
+ if (console->tty.vuart.sirq) {
+ tty_set_sysfs_attr(console, "sirq", console->tty.vuart.sirq);
}
- console->tty_fd = open(console->tty_dev, O_RDWR);
- if (console->tty_fd <= 0) {
- warn("Can't open tty %s", console->tty_dev);
+ if (console->tty.vuart.lpc_addr) {
+ tty_set_sysfs_attr(console, "lpc_address",
+ console->tty.vuart.lpc_addr);
+ }
+}
+
+static int tty_init_io(struct console *console)
+{
+ console->tty.fd = open(console->tty.dev, O_RDWR);
+ if (console->tty.fd <= 0) {
+ warn("Can't open tty %s", console->tty.dev);
return -1;
}
/* Disable character delay. We may want to later enable this when
* we detect larger amounts of data
*/
- fcntl(console->tty_fd, F_SETFL, FNDELAY);
+ fcntl(console->tty.fd, F_SETFL, FNDELAY);
tty_init_termios(console);
- console->pollfds[console->n_pollers].fd = console->tty_fd;
+ console->pollfds[console->n_pollers].fd = console->tty.fd;
console->pollfds[console->n_pollers].events = POLLIN;
return 0;
}
-static int tty_init(struct console *console, struct config *config,
- const char *tty_arg)
+static int tty_init_vuart(struct console *console, struct config *config)
{
unsigned long parsed;
const char *val;
char *endp;
- int rc;
+
+ assert(console->tty.type == TTY_DEVICE_VUART);
val = config_get_value(config, "lpc-address");
if (val) {
@@ -245,7 +300,7 @@
return -1;
}
- console->tty_lpc_addr = (uint16_t)parsed;
+ console->tty.vuart.lpc_addr = (uint16_t)parsed;
if (endp == optarg) {
warn("Invalid LPC address: '%s'", val);
return -1;
@@ -265,23 +320,25 @@
warn("Invalid LPC SERIRQ: '%s'", val);
}
- console->tty_sirq = (int)parsed;
+ console->tty.vuart.sirq = (int)parsed;
if (endp == optarg) {
warn("Invalid sirq: '%s'", val);
}
}
- val = config_get_value(config, "baud");
- if (val) {
- if (config_parse_baud(&console->tty_baud, val)) {
- warnx("Invalid baud rate: '%s'", val);
- }
- }
+ return 0;
+}
+
+static int tty_init(struct console *console, struct config *config,
+ const char *tty_arg)
+{
+ const char *val;
+ int rc;
if (tty_arg) {
- console->tty_kname = tty_arg;
+ console->tty.kname = tty_arg;
} else if ((val = config_get_value(config, "upstream-tty"))) {
- console->tty_kname = val;
+ console->tty.kname = val;
} else {
warnx("Error: No TTY device specified");
return -1;
@@ -292,13 +349,45 @@
return rc;
}
- rc = tty_init_io(console);
- return rc;
+ switch (console->tty.type) {
+ case TTY_DEVICE_VUART:
+ rc = tty_init_vuart(console, config);
+ if (rc) {
+ return rc;
+ }
+
+ tty_init_vuart_io(console);
+ break;
+ case TTY_DEVICE_UART:
+ val = config_get_value(config, "baud");
+ if (val) {
+ if (config_parse_baud(&console->tty.uart.baud, val)) {
+ warnx("Invalid baud rate: '%s'", val);
+ }
+ }
+ break;
+ case TTY_DEVICE_PTY:
+ break;
+ case TTY_DEVICE_UNDEFINED:
+ default:
+ warnx("Cannot configure unrecognised TTY device");
+ return -1;
+ }
+
+ return tty_init_io(console);
+}
+
+static void tty_fini(struct console *console)
+{
+ if (console->tty.type == TTY_DEVICE_VUART) {
+ free(console->tty.vuart.sysfs_devnode);
+ }
+ free(console->tty.dev);
}
int console_data_out(struct console *console, const uint8_t *data, size_t len)
{
- return write_buf_to_fd(console->tty_fd, data, len);
+ return write_buf_to_fd(console->tty.fd, data, len);
}
/* Read console if from config and prepare a socket name */
@@ -666,7 +755,7 @@
/* process internal fd first */
if (console->pollfds[console->n_pollers].revents) {
- rc = read(console->tty_fd, buf, sizeof(buf));
+ rc = read(console->tty.fd, buf, sizeof(buf));
if (rc <= 0) {
warn("Error reading from tty device");
rc = -1;
@@ -762,14 +851,14 @@
handlers_fini(console);
+ tty_fini(console);
+
out_config_fini:
config_fini(config);
out_free:
free(console->pollers);
free(console->pollfds);
- free(console->tty_sysfs_devnode);
- free(console->tty_dev);
free(console);
return rc == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
diff --git a/console-server.h b/console-server.h
index d275ad8..bd287c8 100644
--- a/console-server.h
+++ b/console-server.h
@@ -78,16 +78,32 @@
typedef enum poller_ret (*poller_timeout_fn_t)(struct handler *handler,
void *data);
+enum tty_device {
+ TTY_DEVICE_UNDEFINED = 0,
+ TTY_DEVICE_VUART,
+ TTY_DEVICE_UART,
+ TTY_DEVICE_PTY,
+};
+
/* Console server structure */
struct console {
- const char *tty_kname;
- char *tty_sysfs_devnode;
- char *tty_dev;
+ struct {
+ const char *kname;
+ char *dev;
+ int fd;
+ enum tty_device type;
+ union {
+ struct {
+ char *sysfs_devnode;
+ int sirq;
+ uint16_t lpc_addr;
+ } vuart;
+ struct {
+ speed_t baud;
+ } uart;
+ };
+ } tty;
const char *console_id;
- int tty_sirq;
- uint16_t tty_lpc_addr;
- speed_t tty_baud;
- int tty_fd;
/* Socket name starts with null character hence we need length */
socket_path_t socket_name;