static void mppe_GetMasterKey(uint8_t *nt_hashhash,uint8_t *nt_response,
uint8_t *masterkey)
{
uint8_t digest[20];
fr_SHA1_CTX Context;
fr_SHA1Init(&Context);
fr_SHA1Update(&Context,nt_hashhash,16);
fr_SHA1Update(&Context,nt_response,24);
fr_SHA1Update(&Context,magic1,27);
fr_SHA1Final(digest,&Context);
memcpy(masterkey,digest,16);
}
/*
* challenge_hash() is used by mschap2() and auth_response()
* implements RFC2759 ChallengeHash()
* generates 64 bit challenge
*/
void mschap_challenge_hash(uint8_t const *peer_challenge,
uint8_t const *auth_challenge,
char const *user_name, uint8_t *challenge )
{
fr_SHA1_CTX Context;
uint8_t hash[20];
fr_SHA1Init(&Context);
fr_SHA1Update(&Context, peer_challenge, 16);
fr_SHA1Update(&Context, auth_challenge, 16);
fr_SHA1Update(&Context, (uint8_t const *) user_name,
strlen(user_name));
fr_SHA1Final(hash, &Context);
memcpy(challenge, hash, 8);
}
/**
* @brief Calculate the SHA1 hash of a string.
*
* Example: "%{sha1:foo}" == "0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33"
*/
static size_t sha1_xlat(UNUSED void *instance, REQUEST *request,
char *fmt, char *out, size_t outlen,
UNUSED RADIUS_ESCAPE_STRING func)
{
char buffer[1024];
uint8_t digest[20];
int i;
fr_SHA1_CTX ctx;
if (!radius_xlat(buffer, sizeof(buffer), fmt, request, func)) {
*out = '\0';
return 0;
}
fr_SHA1Init(&ctx);
fr_SHA1Update(&ctx, (void *) buffer, strlen(buffer));
fr_SHA1Final(digest, &ctx);
if (outlen < 41) {
snprintf(out, outlen, "sha1_overflow");
return strlen(out);
}
for (i = 0; i < 20; i++) {
snprintf(out + i * 2, 3, "%02x", digest[i]);
}
return strlen(out);
}
/**
* @brief Calculate the SHA1 hash of a string.
*
* Example: "%{sha1:foo}" == "0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33"
*/
static size_t sha1_xlat(UNUSED void *instance, UNUSED REQUEST *request,
char const *fmt, char *out, size_t outlen)
{
uint8_t digest[16];
int i, len;
fr_SHA1_CTX ctx;
/*
* We need room for at least one octet of output.
*/
if (outlen < 3) {
*out = '\0';
return 0;
}
fr_SHA1Init(&ctx);
fr_SHA1Update(&ctx, (const void *) fmt, strlen(fmt));
fr_SHA1Final(digest, &ctx);
/*
* Each digest octet takes two hex digits, plus one for
* the terminating NUL. SHA1 is 160 bits (20 bytes)
*/
len = (outlen / 2) - 1;
if (len > 20) len = 20;
for (i = 0; i < len; i++) {
snprintf(out + i * 2, 3, "%02x", digest[i]);
}
return strlen(out);
}
static void calc_sha1_digest(uint8_t *buffer, uint8_t const *challenge,
size_t challen, char const *password)
{
uint8_t buf[1024];
int i;
fr_SHA1_CTX context;
memset(buf, 0, 1024);
memset(buf, 0x36, 64);
for(i=0; i<64 && password[i]; i++) buf[i]^=password[i];
memcpy(buf+64, challenge, challen);
fr_SHA1Init(&context);
fr_SHA1Update(&context,buf,64+challen);
memset(buf, 0x5c, 64);
for(i=0; i<64 && password[i]; i++) buf[i]^=password[i];
fr_SHA1Final(buf+64,&context);
fr_SHA1Init(&context);
fr_SHA1Update(&context,buf,64+20);
fr_SHA1Final(buffer,&context);
}
/*
* auth_response() generates MS-CHAP v2 SUCCESS response
* according to RFC 2759 GenerateAuthenticatorResponse()
* returns 42-octet response string
*/
void mschap_auth_response(char const *username,
uint8_t const *nt_hash_hash,
uint8_t const *ntresponse,
uint8_t const *peer_challenge, uint8_t const *auth_challenge,
char *response)
{
fr_SHA1_CTX Context;
static const uint8_t magic1[39] =
{ 0x4D, 0x61, 0x67, 0x69, 0x63, 0x20, 0x73, 0x65, 0x72, 0x76,
0x65, 0x72, 0x20, 0x74, 0x6F, 0x20, 0x63, 0x6C, 0x69, 0x65,
0x6E, 0x74, 0x20, 0x73, 0x69, 0x67, 0x6E, 0x69, 0x6E, 0x67,
0x20, 0x63, 0x6F, 0x6E, 0x73, 0x74, 0x61, 0x6E, 0x74
};
static const uint8_t magic2[41] =
{ 0x50, 0x61, 0x64, 0x20, 0x74, 0x6F, 0x20, 0x6D, 0x61, 0x6B,
0x65, 0x20, 0x69, 0x74, 0x20, 0x64, 0x6F, 0x20, 0x6D, 0x6F,
0x72, 0x65, 0x20, 0x74, 0x68, 0x61, 0x6E, 0x20, 0x6F, 0x6E,
0x65, 0x20, 0x69, 0x74, 0x65, 0x72, 0x61, 0x74, 0x69, 0x6F,
0x6E
};
static char const hex[16] = "0123456789ABCDEF";
size_t i;
uint8_t challenge[8];
uint8_t digest[20];
fr_SHA1Init(&Context);
fr_SHA1Update(&Context, nt_hash_hash, 16);
fr_SHA1Update(&Context, ntresponse, 24);
fr_SHA1Update(&Context, magic1, 39);
fr_SHA1Final(digest, &Context);
mschap_challenge_hash(peer_challenge, auth_challenge, username, challenge);
fr_SHA1Init(&Context);
fr_SHA1Update(&Context, digest, 20);
fr_SHA1Update(&Context, challenge, 8);
fr_SHA1Update(&Context, magic2, 41);
fr_SHA1Final(digest, &Context);
/*
* Encode the value of 'Digest' as "S=" followed by
* 40 ASCII hexadecimal digits and return it in
* AuthenticatorResponse.
* For example,
* "S=0123456789ABCDEF0123456789ABCDEF01234567"
*/
response[0] = 'S';
response[1] = '=';
/*
* The hexadecimal digits [A-F] MUST be uppercase.
*/
for (i = 0; i < sizeof(digest); i++) {
response[2 + (i * 2)] = hex[(digest[i] >> 4) & 0x0f];
response[3 + (i * 2)] = hex[digest[i] & 0x0f];
}
}
static void mppe_GetAsymmetricStartKey(uint8_t *masterkey,uint8_t *sesskey,
int keylen,int issend)
{
uint8_t digest[20];
const uint8_t *s;
fr_SHA1_CTX Context;
memset(digest,0,20);
if(issend) {
s = magic3;
} else {
s = magic2;
}
fr_SHA1Init(&Context);
fr_SHA1Update(&Context,masterkey,16);
fr_SHA1Update(&Context,SHSpad1,40);
fr_SHA1Update(&Context,s,84);
fr_SHA1Update(&Context,SHSpad2,40);
fr_SHA1Final(digest,&Context);
memcpy(sesskey,digest,keylen);
}
void eapsim_calculate_keys(struct eapsim_keys *ek)
{
fr_SHA1_CTX context;
uint8_t fk[160];
unsigned char buf[256];
unsigned char *p;
unsigned int blen;
p = buf;
memcpy(p, ek->identity, ek->identitylen); p = p+ek->identitylen;
memcpy(p, ek->Kc[0], EAPSIM_Kc_SIZE); p = p+EAPSIM_Kc_SIZE;
memcpy(p, ek->Kc[1], EAPSIM_Kc_SIZE); p = p+EAPSIM_Kc_SIZE;
memcpy(p, ek->Kc[2], EAPSIM_Kc_SIZE); p = p+EAPSIM_Kc_SIZE;
memcpy(p, ek->nonce_mt, sizeof(ek->nonce_mt)); p=p+sizeof(ek->nonce_mt);
memcpy(p, ek->versionlist, ek->versionlistlen);p=p+ek->versionlistlen;
memcpy(p, ek->versionselect, sizeof(ek->versionselect)); p=p+sizeof(ek->versionselect);
/* *p++ = ek->versionselect[1]; */
blen = p - buf;
#if defined(TEST_CASE) || defined(DUMP_EAPSIM_KEYS)
{
unsigned int i, j, k;
j=0; k=0;
printf("SHA1buffer was: ");
for (i = 0; i < blen; i++) {
if(j==4) {
printf("_");
j=0;
}
if(k==20) {
printf("\n ");
k=0;
j=0;
}
j++;
k++;
printf("%02x", buf[i]);
}
printf("\n");
}
#endif
/* do the master key first */
fr_SHA1Init(&context);
fr_SHA1Update(&context, buf, blen);
fr_SHA1Final(ek->master_key, &context);
/*
* now use the PRF to expand it, generated K_aut, K_encr,
* MSK and EMSK.
*/
fips186_2prf(ek->master_key, fk);
/* split up the result */
memcpy(ek->K_encr, fk + 0, 16); /* 128 bits for encryption */
memcpy(ek->K_aut, fk + 16, EAPSIM_AUTH_SIZE); /*128 bits for auth */
memcpy(ek->msk, fk + 32, 64); /* 64 bytes for Master Session Key */
memcpy(ek->emsk, fk + 96, 64); /* 64- extended Master Session Key */
}
void
fr_hmac_sha1(const uint8_t *text, int text_len,
const uint8_t *key, int key_len,
uint8_t *digest)
{
fr_SHA1_CTX context;
uint8_t k_ipad[65]; /* inner padding -
* key XORd with ipad
*/
uint8_t k_opad[65]; /* outer padding -
* key XORd with opad
*/
uint8_t tk[20];
int i;
/* if key is longer than 64 bytes reset it to key=SHA1(key) */
if (key_len > 64) {
fr_SHA1_CTX tctx;
fr_SHA1Init(&tctx);
fr_SHA1Update(&tctx, key, key_len);
fr_SHA1Final(tk, &tctx);
key = tk;
key_len = 20;
}
#ifdef HMAC_SHA1_DATA_PROBLEMS
if(sha1_data_problems)
{
int j,k;
printf("\nhmac-sha1 key(%d): ", key_len);
j=0; k=0;
for (i = 0; i < key_len; i++) {
if(j==4) {
printf("_");
j=0;
}
j++;
printf("%02x", key[i]);
}
printf("\nDATA: (%d) ",text_len);
j=0; k=0;
for (i = 0; i < text_len; i++) {
if(k==20) {
printf("\n ");
k=0;
j=0;
}
if(j==4) {
printf("_");
j=0;
}
k++;
j++;
printf("%02x", text[i]);
}
printf("\n");
}
#endif
/*
* the HMAC_SHA1 transform looks like:
*
* SHA1(K XOR opad, SHA1(K XOR ipad, text))
*
* where K is an n byte key
* ipad is the byte 0x36 repeated 64 times
* opad is the byte 0x5c repeated 64 times
* and text is the data being protected
*/
/* start out by storing key in pads */
memset( k_ipad, 0, sizeof(k_ipad));
memset( k_opad, 0, sizeof(k_opad));
memcpy( k_ipad, key, key_len);
memcpy( k_opad, key, key_len);
/* XOR key with ipad and opad values */
for (i = 0; i < 64; i++) {
k_ipad[i] ^= 0x36;
k_opad[i] ^= 0x5c;
}
/*
* perform inner SHA1
*/
fr_SHA1Init(&context); /* init context for 1st
* pass */
fr_SHA1Update(&context, k_ipad, 64); /* start with inner pad */
fr_SHA1Update(&context, text, text_len); /* then text of datagram */
fr_SHA1Final(digest, &context); /* finish up 1st pass */
/*
* perform outer MD5
*/
fr_SHA1Init(&context); /* init context for 2nd
* pass */
fr_SHA1Update(&context, k_opad, 64); /* start with outer pad */
fr_SHA1Update(&context, digest, 20); /* then results of 1st
* hash */
fr_SHA1Final(digest, &context); /* finish up 2nd pass */
#ifdef HMAC_SHA1_DATA_PROBLEMS
if(sha1_data_problems)
{
int j;
printf("\nhmac-sha1 mac(20): ");
j=0;
for (i = 0; i < 20; i++) {
if(j==4) {
printf("_");
j=0;
}
j++;
printf("%02x", digest[i]);
}
printf("\n");
}
#endif
}
