Refactoring TOTP/HOTP command line flags

diff --git a/ykchalresp.c b/ykchalresp.c
index 2320aef594070dd11c339e7a4e1b9abe05556864..3773df76774d2e906d20bc538a3c493f6d819770 100644 (file)
--- a/ykchalresp.c
+++ b/ykchalresp.c
@@ -43,7 +43,7 @@
 #include <ykpers-version.h>
 
 const char *usage =
-       "Usage: ykchalresp [options] challenge\n"
+       "Usage: ykchalresp [options] [challenge]\n"
        "\n"
        "Options :\n"
        "\n"
@@ -53,8 +53,9 @@ const char *usage =
        "\t-Y        Send a 6 byte Yubico challenge.\n"
        "\t-N        Abort if Yubikey requires button press.\n"
        "\t-x        Challenge is hex encoded.\n"
-       "\t-t        Calculate TOTP (length 6, implies -H)\n"
-       "\t-8        8 Digit TOTP (usw with -t)\n"
+       "\t-t        Time based challenge (for TOTP)\n"
+       "\t-6        Output 6 digit HOTP/TOTP code\n"
+       "\t-8        Output 8 digit HOTP/TOTP code\n"
        "\n"
        "\t-v        verbose\n"
        "\t-V        tool version\n"
@@ -62,7 +63,7 @@ const char *usage =
        "\n"
        "\n"
        ;
-const char *optstring = "128xvhHtYNV";
+const char *optstring = "1268xvhHtYNV";
 
 static void report_yk_error(void)
 {
@@ -80,7 +81,7 @@ static void report_yk_error(void)
 static int parse_args(int argc, char **argv,
               int *slot, bool *verbose,
               unsigned char **challenge, unsigned int *challenge_len,
-              bool *hmac, bool *may_block, bool *totp, bool *eight,
+              bool *hmac, bool *may_block, bool *totp, int *digits,
               int *exit_code)
 {
        int c;
@@ -104,8 +105,11 @@ static int parse_args(int argc, char **argv,
                        *totp = true;
                        *hmac = true;
                        break;
+               case '6':
+                       *digits = 6;
+                       break;
                case '8':
-                       *eight = true;
+                       *digits = 8;
                        break;
                case 'Y':
                        *hmac = false;
@@ -212,7 +216,7 @@ static int check_firmware(YK_KEY *yk, bool verbose)
 
 static int challenge_response(YK_KEY *yk, int slot,
                       unsigned char *challenge, unsigned int len,
-                      bool hmac, bool may_block, bool verbose, bool totp, bool eight)
+                      bool hmac, bool may_block, bool verbose, bool totp, int digits )
 {
        unsigned char response[64];
        unsigned char output_buf[(SHA1_MAX_BLOCK_SIZE * 2) + 1];
@@ -246,13 +250,13 @@ static int challenge_response(YK_KEY *yk, int slot,
        /* HMAC responses are 160 bits, Yubico 128 */
        expect_bytes = (hmac == true) ? 20 : 16;
 
-       if(totp){
+       if(totp && digits){
                offset   =  response[19] & 0xf ;
                bin_code = (response[offset]  & 0x7f) << 24
                | (response[offset+1] & 0xff) << 16
                | (response[offset+2] & 0xff) <<  8
                | (response[offset+3] & 0xff) ;
-               if(eight){
+               if(digits == 8){
                        bin_code = bin_code % 100000000;
                        printf("%08u\n", bin_code);
                        return 1;
@@ -282,7 +286,7 @@ int main(int argc, char **argv)
        bool hmac = true;
        bool may_block = true;
        bool totp = false;
-       bool eight = false;
+       int digits = 0;
        unsigned char *challenge;
        unsigned int challenge_len;
        int slot = 1;
@@ -292,7 +296,7 @@ int main(int argc, char **argv)
        if (! parse_args(argc, argv,
                         &slot, &verbose,
                         &challenge, &challenge_len,
-                        &hmac, &may_block, &totp, &eight,
+                        &hmac, &may_block, &totp, &digits,
                         &exit_code))
                exit(exit_code);
 
@@ -313,7 +317,7 @@ int main(int argc, char **argv)
 
        if (! challenge_response(yk, slot,
                                 challenge, challenge_len,
-                                hmac, may_block, verbose, totp, eight)) {
+                                hmac, may_block, verbose, totp, digits)) {
                exit_code = 1;
                goto err;
        }