support starting telnetd if requested

docs/palera1n.1

@@ -9,7 +9,7 @@
 .Nd arm64 iOS/iPadOS/tvOS 15.0-17.5, bridgeOS 5.0-8.3 jailbreaking tool
 .Sh SYNOPSIS
 .Nm
-.Op Fl cCdDEfhIlLnpRsSvV
+.Op Fl cCdDEfhIlLnpRsSTvV
 .Op Fl e Ar Boot arguments
 .Op Fl k Ar Pongo image
 .Op Fl o Ar overlay file
@@ -221,6 +221,8 @@ section below) will be executed. The loader app and the built in SSH server can
 as well as any jailbreak-specific apps you have installed.
 .It Fl S , -no-colors
 Disable colors on the command line. External programs like checkra1n clones may still output colors.
+.It Fl T , -telnetd
+Enable the TELNET daemon on port 46, all interfaces. Please note that there is no authentication and is therefore insecure.
 .It Fl v , -debug-logging
 Enable debug logging. The option may be repeated for extra verbosity.
 .It Fl V , -verbose-boot

include/paleinfo.h

@@ -47,6 +47,7 @@ typedef uint64_t palerain_option_t;
 // #define palerain_option_emerg_mode        (UINT64_C(1) << 29) /* emergency mode (early boot usb shell) */
 #define palerain_option_jbinit_log_to_file   (UINT64_C(1) << 30) /* deprecated (kept for compatibility) */
 #define palerain_option_cli                  (UINT64_C(1) << 31) /* CLI mode */
+#define palerain_option_telnetd              (UINT64_C(1) << 32) /* Enable TELNET daemon */
 
 #define palerain_option_flower_chain         (UINT64_C(1) << 61) /* Flower chain */
 #define palerain_option_test1                (UINT64_C(1) << 62) /* Developer test option 1 */

src/optparse.c

@@ -39,6 +39,7 @@ static struct option longopts[] = {
 	{"force-revert", no_argument, NULL, palerain_option_case_force_revert},
 	{"no-colors", no_argument, NULL, 'S'},
 	{"safe-mode", no_argument, NULL, 's'},
+	{"telnetd", no_argument, NULL, 'T'},
 	{"version", no_argument, NULL, palerain_option_case_version},
 	{"override-libcheckra1nhelper", required_argument, NULL, palerain_option_case_libcheckra1nhelper_path},
 	{"override-pongo", required_argument, NULL, 'k'},
@@ -65,7 +66,7 @@ static int usage(int e, char* prog_name)
 {
 	fprintf(stderr,
 	"Usage: %s [-"
-	"DEhpvVldsSLRnPI"
+	"DEhpvVldsSTLRnPI"
 #ifdef DEV_BUILD
 			"12"
 #endif
@@ -113,6 +114,7 @@ static int usage(int e, char* prog_name)
 			"\t-R, --reboot-device\t\t\tReboot connected device in normal mode\n"
 			"\t-s, --safe-mode\t\t\t\tEnter safe mode\n"
 			"\t-S, --no-colors\t\t\t\tDisable colors on the command line\n"
+			"\t-T, --telnetd\t\t\t\tEnable TELNET daemon on port 46 (insecure)\n"
 			"\t-v, --debug-logging\t\t\tEnable debug logging\n"
 			"\t\tThis option can be repeated for extra verbosity.\n"
 			"\t-V, --verbose-boot\t\t\tVerbose boot\n"
@@ -132,7 +134,7 @@ int optparse(int argc, char* argv[]) {
 	int opt;
 	int index;
 	while ((opt = getopt_long(argc, argv,
-	"DEhpvVlLdsStRnPIe:o:r:K:k:i:"
+	"DEhpvVlLdsSTtRnPIe:o:r:K:k:i:"
 #ifdef DEV_BUILD
 	"12"
 #endif
@@ -216,6 +218,9 @@ int optparse(int argc, char* argv[]) {
 			tui_options_safe_mode = true;
 #endif
 			break;
+		case 'T':
+			palerain_flags |= palerain_option_telnetd;
+			break;
 		case 'k':
 			if (access(optarg, F_OK) != 0) {
 				LOG(LOG_FATAL, "Cannot access pongo file at %s: %d (%s)", optarg, errno, strerror(errno));
@@ -360,6 +365,10 @@ int optparse(int argc, char* argv[]) {
 		return 0;
 	}
 
+	if (palerain_flags & palerain_option_telnetd) {
+		LOG(LOG_WARNING, "telnetd is enabled");
+	}
+
 	if ((strstr(xargs_cmd, "serial=") != NULL) && !force_use_verbose_boot && (palerain_flags & palerain_option_setup_rootful)) {
 		palerain_flags &= ~palerain_option_verbose_boot;
 	}