diff options
Diffstat (limited to 'usr.sbin/xntpd/authstuff/keyparity.c')
| -rw-r--r-- | usr.sbin/xntpd/authstuff/keyparity.c | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/usr.sbin/xntpd/authstuff/keyparity.c b/usr.sbin/xntpd/authstuff/keyparity.c new file mode 100644 index 000000000000..45a706173b43 --- /dev/null +++ b/usr.sbin/xntpd/authstuff/keyparity.c @@ -0,0 +1,279 @@ +/* keyparity.c,v 3.1 1993/07/06 01:04:57 jbj Exp + * keyparity - add parity bits to key and/or change an ascii key to binary + */ + +#include <stdio.h> +#include <sys/types.h> +#include <ctype.h> + +#include "ntp_string.h" +#include "ntp_stdlib.h" + +#define STREQ(a, b) (*(a) == *(b) && strcmp((a), (b)) == 0) + +/* + * Types of ascii representations for keys. "Standard" means a 64 bit + * hex number in NBS format, i.e. with the low order bit of each byte + * a parity bit. "NTP" means a 64 bit key in NTP format, with the + * high order bit of each byte a parity bit. "Ascii" means a 1-to-8 + * character string whose ascii representation is used as the key. + */ +#define KEY_TYPE_STD 1 +#define KEY_TYPE_NTP 2 +#define KEY_TYPE_ASCII 3 + +#define STD_PARITY_BITS 0x01010101 + +char *progname; +int debug; + +int ntpflag = 0; +int stdflag = 0; +int asciiflag = 0; +int ntpoutflag = 0; +int gotoopt = 0; + +static int parity P((U_LONG *)); +static int decodekey P((int, char *, U_LONG *)); +static void output P((U_LONG *, int)); + +/* + * main - parse arguments and handle options + */ +void +main(argc, argv) +int argc; +char *argv[]; +{ + int c; + int errflg = 0; + int keytype; + U_LONG key[2]; + extern int optind; + extern char *optarg; + + progname = argv[0]; + while ((c = getopt_l(argc, argv, "adno:s")) != EOF) + switch (c) { + case 'a': + asciiflag = 1; + break; + case 'd': + ++debug; + break; + case 'n': + ntpflag = 1; + break; + case 's': + stdflag = 1; + break; + case 'o': + if (*optarg == 'n') { + ntpoutflag = 1; + gotoopt = 1; + } else if (*optarg == 's') { + ntpoutflag = 0; + gotoopt = 1; + } else { + (void) fprintf(stderr, + "%s: output format must be `n' or `s'\n", + progname); + errflg++; + } + break; + default: + errflg++; + break; + } + if (errflg || optind == argc) { + (void) fprintf(stderr, + "usage: %s -n|-s [-a] [-o n|s] key [...]\n", + progname); + exit(2); + } + + if (!ntpflag && !stdflag) { + (void) fprintf(stderr, + "%s: one of either the -n or -s flags must be specified\n", + progname); + exit(2); + } + + if (ntpflag && stdflag) { + (void) fprintf(stderr, + "%s: only one of the -n and -s flags may be specified\n", + progname); + exit(2); + } + + if (!gotoopt) { + if (ntpflag) + ntpoutflag = 1; + } + + if (asciiflag) + keytype = KEY_TYPE_ASCII; + else if (ntpflag) + keytype = KEY_TYPE_NTP; + else + keytype = KEY_TYPE_STD; + + for (; optind < argc; optind++) { + if (!decodekey(keytype, argv[optind], key)) { + (void) fprintf(stderr, + "%s: format of key %s invalid\n", + progname, argv[optind]); + exit(1); + } + (void) parity(key); + output(key, ntpoutflag); + } + exit(0); +} + + + +/* + * parity - set parity on a key/check for odd parity + */ +static int +parity(key) + U_LONG *key; +{ + U_LONG mask; + int parity_err; + int bitcount; + int half; + int byte; + int i; + + /* + * Go through counting bits in each byte. Check to see if + * each parity bit was set correctly. If not, note the error + * and set it right. + */ + parity_err = 0; + for (half = 0; half < 2; half++) { /* two halves of key */ + mask = 0x80000000; + for (byte = 0; byte < 4; byte++) { /* 4 bytes per half */ + bitcount = 0; + for (i = 0; i < 7; i++) { /* 7 data bits / byte */ + if (key[half] & mask) + bitcount++; + mask >>= 1; + } + + /* + * If bitcount is even, parity must be set. If + * bitcount is odd, parity must be clear. + */ + if ((bitcount & 0x1) == 0) { + if (!(key[half] & mask)) { + parity_err++; + key[half] |= mask; + } + } else { + if (key[half] & mask) { + parity_err++; + key[half] &= ~mask; + } + } + mask >>= 1; + } + } + + /* + * Return the result of the parity check. + */ + return (parity_err == 0); +} + + +static int +decodekey(keytype, str, key) + int keytype; + char *str; + U_LONG *key; +{ + u_char keybytes[8]; + char *cp; + char *xdigit; + int len; + int i; + static char *hex = "0123456789abcdef"; + + cp = str; + len = strlen(cp); + if (len == 0) + return 0; + + switch(keytype) { + case KEY_TYPE_STD: + case KEY_TYPE_NTP: + if (len != 16) /* Lazy. Should define constant */ + return 0; + /* + * Decode hex key. + */ + key[0] = 0; + key[1] = 0; + for (i = 0; i < 16; i++) { + if (!isascii(*cp)) + return 0; + xdigit = strchr(hex, isupper(*cp) ? tolower(*cp) : *cp); + cp++; + if (xdigit == 0) + return 0; + key[i>>3] <<= 4; + key[i>>3] |= (U_LONG)(xdigit - hex) & 0xf; + } + + /* + * If this is an NTP format key, put it into NBS format + */ + if (keytype == KEY_TYPE_NTP) { + for (i = 0; i < 2; i++) + key[i] = ((key[i] << 1) & ~STD_PARITY_BITS) + | ((key[i] >> 7) & STD_PARITY_BITS); + } + break; + + case KEY_TYPE_ASCII: + /* + * Make up key from ascii representation + */ + bzero(keybytes, sizeof(keybytes)); + for (i = 0; i < 8 && i < len; i++) + keybytes[i] = *cp++ << 1; + key[0] = keybytes[0] << 24 | keybytes[1] << 16 + | keybytes[2] << 8 | keybytes[3]; + key[1] = keybytes[4] << 24 | keybytes[5] << 16 + | keybytes[6] << 8 | keybytes[7]; + break; + + default: + /* Oh, well */ + return 0; + } + + return 1; +} + + +/* + * output - print a hex key on the standard output + */ +static void +output(key, ntpformat) + U_LONG *key; + int ntpformat; +{ + int i; + + if (ntpformat) { + for (i = 0; i < 2; i++) + key[i] = ((key[i] & ~STD_PARITY_BITS) >> 1) + | ((key[i] & STD_PARITY_BITS) << 7); + } + (void) printf("%08x%08x\n", key[0], key[1]); +} |