eight digit hexadecimal 'password'.
It is NOT necessary to have the device generate a 'seed' using "ATSE [MODEL-ID]"
- because this tool can generate the seed from the device's first (base) MAC address
- *provided* the "ATSE" command has NOT been executed since the device last booted.
+ because this tool can generate the seed from the device's first (base) MAC address.
- Access to the device's console via a serial UART port is required to enter the password.
+ When the device generates a seed it combines the number of seconds since 1970-01-01 00:00:00
+ with the router MAC address. Both are encoded in a single 6-byte hexadecimal
+
+ Each value is truncated to its 3 least significant bytes so, for example:
+
+ $ date +%F.%T; echo "obase=16;$(date +%s)" | bc
+ 2016-03-26.23:06:32
+ 56F715F8
+ # MAC Address: EC:43:F6:46:C0:80
+
+ becomes F715F8 concatenated with 46C080
+
+ CFE> ATSE DSL-2492GNAU-B1BC
+ F715F846C080 <<<< last 3 bytes of MAC address
+ ^^^^^^
+ seconds since 1970-01-01 00:00:00 (2016-03-26 23:06:32)
+
+ *NOTE: the default seed after power-up is 000000 so no time value needs to be specifed
+ if "ATSE <model-id-string>" has not been executed on the device.
+
+ Access to the device's console via a serial UART port, or a network telnet/ssh session,
+ is required to enter the password.
So, for a device with base MAC address (reported by the CFE during boot) E.g:
OK
*** command status = 0
- The tool can accept a timestamp as 6 hexadecimal characters (useful for testing the algorithm):
+ The tool can accept a timestamp as 8 hexadecimal characters (useful for testing the algorithm):
./cfe_gen_pass -t 0FF020 -s ec:43:f6:46:c0:80 -p
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
+#include <time.h>
-static const float VERSION = 1.1f;
-static const size_t TIMESTAMP_SIZE = 6;
+static const float VERSION = 1.3f;
+static const size_t TIMESTAMP_SIZE = 8;
static const size_t SEED_SIZE = 12;
static const size_t PASSWORD_SIZE = 8;
static const size_t MESSAGE_SIZE = 128;
static const size_t MAC_ADDR_SIZE = 17;
+static const size_t DATESTRING_SIZE = 20;
static void
pr_usage()
"Usage:\n"
" -v show version\n"
" -s 00:01:02:03:04:05 create seed from MAC address\n"
- " -t 000000 millisecond timestamp since boot\n"
+ " -t [00000000] seconds since 1970-01-01 (defaults to NOW) \n"
" -p [SEED] generate password (with optional seed)\n\n"
" E.g. -s 01:02:03:04:05 \n"
" -s 01:02:03:04:05 -p\n"
pr_error_exit(unsigned int usage, const char *error, ...)
{
va_list args;
- char error_message[MESSAGE_SIZE];
+ char error_message[MESSAGE_SIZE + 1];
if (!error) return;
va_start(args, error);
- (void) vsnprintf(error_message, MESSAGE_SIZE, error, args);
+ (void) vsnprintf(error_message, MESSAGE_SIZE + 1, error, args);
va_end(args);
fprintf(stderr, "Error: %s\n", error_message);
size_t i;
char *mac_ptr = mac + 9;
size_t ts_len = strlen(timestamp);
- for (i = 0; i <= SEED_SIZE; ++i) {
- /* if no timestamp assume CFE get_time() returned 0 and CFE g_pw_timestamp == 0x00000000 */
- if (i < 6)
- seed[i] = ts_len ? timestamp[i] : '0';
- else {
- if (*mac_ptr == ':' || *mac_ptr == '-')
- ++mac_ptr;
- seed[i] = *mac_ptr++;
+ if (ts_len == TIMESTAMP_SIZE) {
+ for (i = 0; i < SEED_SIZE; ++i) {
+ if (i < 6) // first half of seed is the truncated timestamp
+ seed[i] = timestamp[i+2];
+ else { // second half is the truncated MAC address
+ if (*mac_ptr == ':' || *mac_ptr == '-')
+ ++mac_ptr;
+ seed[i] = *mac_ptr++;
+ }
}
- }
- result = 1;
+ result = 1;
+ } else
+ pr_error_exit(0, "Timestamp ('%s') should be %d hexadecimal characters e.g: 56F715F8", timestamp, TIMESTAMP_SIZE);
} else
- pr_error_exit(0, "MAC-ADDR should be 17 characters, e.g: 00:01:02:03:04:05");
+ pr_error_exit(0, "MAC-ADDR should be %d characters, e.g: 00:01:02:03:04:05", MAC_ADDR_SIZE);
return result;
}
char timestamp[TIMESTAMP_SIZE + 1];
char seed[SEED_SIZE + 1];
char password[PASSWORD_SIZE + 1];
+ char date_string[DATESTRING_SIZE + 1];
unsigned int opt_seed, opt_pass, opt_ts;
- seed[0] = password[0] = 0;
- seed[SEED_SIZE] = password[PASSWORD_SIZE] = timestamp[TIMESTAMP_SIZE] = 0;
+ time_t ts = 0;
+ struct tm *t = NULL;
+ seed[0] = password[0] = timestamp[0] = 0;
+ seed[SEED_SIZE] = password[PASSWORD_SIZE] = 0;
opt_seed = opt_pass = opt_ts = 0;
- strncpy(timestamp, "000000", TIMESTAMP_SIZE);
+ strncpy(timestamp, "00000000", TIMESTAMP_SIZE + 1);
for (arg = 1; arg < (unsigned) argc; ++arg) {
size_t arg_len = strlen(argv[arg]);
++opt_pass;
} else if (opt_ts == 1) {
if (arg_len != TIMESTAMP_SIZE)
- pr_error_exit(1, "timestamp length must be %d characters", TIMESTAMP_SIZE);
+ pr_error_exit(1, "timestamp length must be %d hexadecimal characters", TIMESTAMP_SIZE);
strncpy(timestamp, argv[arg], TIMESTAMP_SIZE);
++opt_ts;
pr_error_exit(1, "password on its own requires a pre-generated seed");
else if (opt_seed && opt_pass && opt_pass != 1)
pr_error_exit(1, "generating seed and password; cannot also accept pre-generated seed");
- else if (opt_ts == 1)
- pr_error_exit(0, "missing timestamp; assuming 000000");
+ else if (opt_pass == 2 && opt_ts)
+ pr_error_exit(1, "seed already contains a timestamp; cannot over-ride it");
+ else if (opt_ts == 1 || opt_pass == 2) { // no timestamp provided; use NOW
+ ts = time(NULL);
+ if (ts)
+ snprintf(timestamp, TIMESTAMP_SIZE + 1, "%08lX", ts);
+ }
+ if (opt_pass == 2) { // try to figure out the correct date-time from the seed
+ // inherits the most significant 2 characters from the NOW time
+ strncpy(timestamp+2, seed, 6);
+ time_t tmp;
+ if (sscanf(timestamp, "%08lx", &tmp))
+ if (tmp > ts-3600 && tmp < ts+3600) // timestamps are so close they must be for the same date
+ ts = tmp;
+ }
+
+ if(opt_ts) { // ts needs to be valid to be converted to a time string
+ if(! sscanf(timestamp, "%08lx", &ts))
+ pr_error_exit(1, "converting timestamp string ('%s') to number", timestamp);
+ }
+ t = gmtime(&ts);
+ strftime(date_string, DATESTRING_SIZE, "%F %T", t);
if (opt_seed)
if (! generate_seed(MAC_ADDR, timestamp, seed))
pr_error_exit(0, "unable to generate password");
if (opt_seed || opt_pass)
- printf("MAC address: %s Timestamp: %s Seed: %s Password: %s\n", MAC_ADDR, timestamp, seed, password);
+ printf("MAC address: %s Timestamp: %s (%s) Seed: %s Password: %s\n", MAC_ADDR, timestamp, date_string, seed, password);
}
return result;
projects / cfe_generate_password.git / blobdiff