diff options
Diffstat (limited to 'crypto/kerberosIV/lib/krb/str2key.c')
-rw-r--r-- | crypto/kerberosIV/lib/krb/str2key.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/crypto/kerberosIV/lib/krb/str2key.c b/crypto/kerberosIV/lib/krb/str2key.c new file mode 100644 index 0000000..2b00fc1 --- /dev/null +++ b/crypto/kerberosIV/lib/krb/str2key.c @@ -0,0 +1,103 @@ +/* This defines the Andrew string_to_key function. It accepts a password + * string as input and converts its via a one-way encryption algorithm to a DES + * encryption key. It is compatible with the original Andrew authentication + * service password database. + */ + +#include "krb_locl.h" + +RCSID("$Id: str2key.c,v 1.10 1997/03/23 03:53:19 joda Exp $"); + +static void +mklower(char *s) +{ + for (; *s; s++) + if ('A' <= *s && *s <= 'Z') + *s = *s - 'A' + 'a'; +} + +/* + * Short passwords, i.e 8 characters or less. + */ +static void +afs_cmu_StringToKey (char *str, char *cell, des_cblock *key) +{ + char password[8+1]; /* crypt is limited to 8 chars anyway */ + int i; + int passlen; + + memset (key, 0, sizeof(key)); + memset(password, 0, sizeof(password)); + + strncpy (password, cell, 8); + passlen = strlen (str); + if (passlen > 8) passlen = 8; + + for (i=0; i<passlen; i++) + password[i] = str[i] ^ cell[i]; /* make sure cell is zero padded */ + + for (i=0; i<8; i++) + if (password[i] == '\0') password[i] = 'X'; + + /* crypt only considers the first 8 characters of password but for some + reason returns eleven characters of result (plus the two salt chars). */ + strncpy((char *)key, (char *)crypt(password, "#~") + 2, sizeof(des_cblock)); + + /* parity is inserted into the LSB so leftshift each byte up one bit. This + allows ascii characters with a zero MSB to retain as much significance + as possible. */ + { char *keybytes = (char *)key; + unsigned int temp; + + for (i = 0; i < 8; i++) { + temp = (unsigned int) keybytes[i]; + keybytes[i] = (unsigned char) (temp << 1); + } + } + des_fixup_key_parity (key); +} + +/* + * Long passwords, i.e 9 characters or more. + */ +static void +afs_transarc_StringToKey (char *str, char *cell, des_cblock *key) +{ + des_key_schedule schedule; + des_cblock temp_key; + des_cblock ivec; + char password[512]; + int passlen; + + strncpy (password, str, sizeof(password)); + if ((passlen = strlen (password)) < sizeof(password)-1) + strncat (password, cell, sizeof(password)-passlen); + if ((passlen = strlen(password)) > sizeof(password)) passlen = sizeof(password); + + memcpy(&ivec, "kerberos", 8); + memcpy(&temp_key, "kerberos", 8); + des_fixup_key_parity (&temp_key); + des_key_sched (&temp_key, schedule); + des_cbc_cksum ((des_cblock *)password, &ivec, passlen, schedule, &ivec); + + memcpy(&temp_key, &ivec, 8); + des_fixup_key_parity (&temp_key); + des_key_sched (&temp_key, schedule); + des_cbc_cksum ((des_cblock *)password, key, passlen, schedule, &ivec); + + des_fixup_key_parity (key); +} + +void +afs_string_to_key(char *str, char *cell, des_cblock *key) +{ + char realm[REALM_SZ+1]; + strncpy(realm, cell, REALM_SZ); + realm[REALM_SZ] = 0; + mklower(realm); + + if (strlen(str) > 8) + afs_transarc_StringToKey (str, realm, key); + else + afs_cmu_StringToKey (str, realm, key); +} |