fetch_key(const unsigned char *challenge, const int challengesize)
{
struct _hash_obj ho = {0};
- int rc;
+ long rc;
int keysize = sizeof(ho.hash);
if ((rc = pcsc_cr(challenge, challengesize, ho.hash, &keysize))) {
int datahashsize = HASHSIZE;
serializer_t srl;
+ if (keysize < CBLKSIZE) {
+ ao.err = "make authobj: key too short";
+ return ao;
+ }
datasize = ((secsize + paysize + HASHSIZE + 4 * sizeof(short) - 1) /
CBLKSIZE + 1) * CBLKSIZE;
data = alloca(datasize);
unsigned long lrc;
int osize = ((serial_size(&srl) -1) / CBLKSIZE + 1) * CBLKSIZE;
- if ((ao.buffer = malloc(osize)) == NULL) {
- ao.err = "authobj: malloc failed";
+ if ((ao.buffer = malloc(osize + paysize)) == NULL) {
+ ao.err = "make authobj: malloc failed";
} else if ((lrc = encrypt(key, CBLKSIZE, data,
ao.buffer, osize))) {
ao.err = crypto_errstr(lrc);
} else {
- ao.authobj = ao.buffer;
- ao.authsize = osize;
+ ao.data = ao.buffer;
+ ao.datasize = osize;
+ if (payload && paysize) {
+ /* payload passthrough */
+ ao.payload = ao.data + osize;
+ memcpy(ao.payload, payload, paysize);
+ ao.paylsize = paysize;
+ }
}
}
return ao;
}
-static int parse_authobj(const unsigned char *key, const int keysize,
- const unsigned char *buffer, const int bufsize,
- unsigned char *secret, int *secsize,
- unsigned char *payload, int *paysize)
+static struct _auth_obj
+parse_authobj(const unsigned char *key, const int keysize,
+ const unsigned char *buffer, const int bufsize)
{
- int datasize = bufsize;
- unsigned char *data = alloca(datasize);
- serializer_t srl;
- int tsize;
- unsigned char myhash[HASHSIZE];
- int myhashsize = HASHSIZE;
- unsigned char theirhash[HASHSIZE];
- int theirhashsize = HASHSIZE;
-
- if (decrypt(key, CBLKSIZE, buffer, data, datasize))
- return 1;
- serial_init(&srl, data, datasize);
- tsize = *secsize;
- *secsize = serial_get(&srl, secret, tsize);
- if (*secsize > tsize || *secsize <= 0) return 1;
- tsize = *paysize;
- *paysize = serial_get(&srl, payload, tsize);
- if (*paysize > tsize || *paysize <= 0) return 1;
- if (hash(data, serial_size(&srl), myhash, &myhashsize))
- return 1;
- theirhashsize = serial_get(&srl, theirhash, theirhashsize);
- if (theirhashsize != HASHSIZE) return 1;
- if ((myhashsize != theirhashsize) ||
- memcmp(myhash, theirhash, myhashsize))
- return 1;
- return 0;
+ unsigned long rc;
+ struct _auth_obj ao = {0};
+
+ if (keysize < CBLKSIZE) {
+ ao.err = "parse authobj: key too short";
+ } else if ((ao.buffer = malloc(bufsize)) == NULL) {
+ ao.err = "parse authobj: malloc failed";
+ } else if ((rc = decrypt(key, CBLKSIZE, buffer, ao.buffer, bufsize))) {
+ ao.err = crypto_errstr(rc);
+ } else {
+ serializer_t srl;
+ unsigned char myhash[HASHSIZE];
+ int myhsize = HASHSIZE;
+ unsigned char *theirhash;
+ int theirhsize;
+ unsigned long rc;
+
+ serial_init(&srl, ao.buffer, bufsize);
+ if (serial_get(&srl, (void**)&ao.data, &ao.datasize)) {
+ ao.err = "parse authobj: too long secret";
+ } else if (serial_get(&srl, (void**)&ao.payload, &ao.paylsize)) {
+ ao.err = "parse authobj: too long payload";
+ } else if ((rc = hash(ao.buffer, serial_size(&srl),
+ myhash, &myhsize))) {
+ ao.err = crypto_errstr(rc);
+ } else if (serial_get(&srl, (void**)&theirhash, &theirhsize)) {
+ ao.err = "parse authobj: too long hash";
+ } else if (theirhsize != HASHSIZE) {
+ ao.err = "parse authobj: hash is of wrong size";
+ } else if ((myhsize != theirhsize) ||
+ memcmp(myhash, theirhash, myhsize)) {
+ ao.err = "parse authobj: hash mismatch";
+ }
+ }
+ return ao;
}
struct _auth_obj new_authobj(const char *userid, const char *password,
const unsigned char *secret, const int secsize,
const unsigned char *payload, const int paysize)
{
- struct _auth_obj ao = {0};
+ struct _auth_obj new_ao = {0};
struct _hash_obj ho_chal, ho_key;
ho_chal = make_challenge(userid, password, nonce);
if (ho_chal.err) {
- ao.err = ho_chal.err;
- return ao;
+ new_ao.err = ho_chal.err;
+ return new_ao;
}
ho_key = make_key(ho_chal.hash, sizeof(ho_chal.hash), secret, secsize);
+ memset(&ho_chal, 0, sizeof(ho_chal));
if (ho_key.err) {
- ao.err = ho_key.err;
- return ao;
+ new_ao.err = ho_key.err;
+ return new_ao;
}
- ao = make_authobj(ho_key.hash, sizeof(ho_key.hash),
+ new_ao = make_authobj(ho_key.hash, sizeof(ho_key.hash),
secret, secsize, payload, paysize);
- memset(&ho_chal, 0, sizeof(ho_chal));
memset(&ho_key, 0, sizeof(ho_key));
- return ao;
+ return new_ao;
}
struct _auth_obj verify_authobj(const char *userid, const char *password,
const char *oldnonce, const char *newnonce,
const unsigned char *authobj, const int authsize)
{
- struct _auth_obj ao = {0};
+ struct _auth_obj old_ao;
+ struct _auth_obj new_ao = {0};
struct _hash_obj ho_chal, ho_key;
ho_chal = make_challenge(userid, password, oldnonce);
if (ho_chal.err) {
- ao.err = ho_chal.err;
- return ao;
+ new_ao.err = ho_chal.err;
+ return new_ao;
}
ho_key = fetch_key(ho_chal.hash, sizeof(ho_chal.hash));
+ memset(&ho_chal, 0, sizeof(ho_chal));
if (ho_key.err) {
- ao.err = ho_key.err;
- return ao;
+ new_ao.err = ho_key.err;
+ return new_ao;
+ }
+ old_ao = parse_authobj(ho_key.hash, sizeof(ho_key.hash),
+ authobj, authsize);
+ memset(&ho_key, 0, sizeof(ho_key));
+ if (old_ao.err) {
+ new_ao.err = old_ao.err;
+ if (old_ao.buffer) free(old_ao.buffer);
+ return new_ao;
}
+
+ ho_chal = make_challenge(userid, password, newnonce);
+ if (ho_chal.err) {
+ new_ao.err = ho_chal.err;
+ return new_ao;
+ }
+ ho_key = make_key(ho_chal.hash, sizeof(ho_chal.hash),
+ old_ao.data, old_ao.datasize);
memset(&ho_chal, 0, sizeof(ho_chal));
+ if (ho_key.err) {
+ new_ao.err = ho_key.err;
+ return new_ao;
+ }
+ new_ao = make_authobj(ho_key.hash, sizeof(ho_key.hash),
+ old_ao.data, old_ao.datasize,
+ old_ao.payload, old_ao.paylsize);
memset(&ho_key, 0, sizeof(ho_key));
- return ao;
+
+ if (old_ao.data) memset(old_ao.data, 0, old_ao.datasize);
+ if (old_ao.payload) memset(old_ao.payload, 0, old_ao.paylsize);
+ if (old_ao.buffer) free(old_ao.buffer);
+ return new_ao;
}
struct _auth_obj reload_authobj(const char *userid, const char *password,
const unsigned char *authobj, const int authsize,
const unsigned char *payload, const int paysize)
{
- struct _auth_obj ao = {0};
+ struct _auth_obj old_ao;
+ struct _auth_obj new_ao = {0};
struct _hash_obj ho_chal, ho_key;
ho_chal = make_challenge(userid, password, oldnonce);
if (ho_chal.err) {
- ao.err = ho_chal.err;
- return ao;
+ new_ao.err = ho_chal.err;
+ return new_ao;
}
ho_key = fetch_key(ho_chal.hash, sizeof(ho_chal.hash));
+ memset(&ho_chal, 0, sizeof(ho_chal));
if (ho_key.err) {
- ao.err = ho_key.err;
- return ao;
+ new_ao.err = ho_key.err;
+ return new_ao;
}
- memset(&ho_chal, 0, sizeof(ho_chal));
memset(&ho_key, 0, sizeof(ho_key));
- return ao;
+ return new_ao;
}
#include <stdio.h>
#include <string.h>
+#include <stdlib.h>
#include "authobj.h"
#include "crypto.h"
0xfc, 0xa0, 0xfc, 0x56, 0x56};
const unsigned char *payload = (unsigned char *)
"To authorize or not to authorize?";
- unsigned char authobj[128];
- int authsize = sizeof(authobj);
- unsigned char challenge[128];
- int challengesize = sizeof(challenge);
- int rc;
- unsigned char key[20];
- int keysize = sizeof(key);
- unsigned char newsecret[20];
- int newsecsize = sizeof(newsecret);
- unsigned char newload[128];
- int newloadsize=sizeof(newload);
+ int i;
+ struct _auth_obj ao;
+ struct _auth_obj nao;
- rc = make_authobj(id, pass, nonce, secret, sizeof(secret),
- payload, strlen((char *)payload),
- authobj, &authsize);
- printf("make_authobj() rc=%d size=%d\n", rc, authsize);
- if (rc) return rc;
-
- rc = make_challenge(id, pass, nonce, challenge, &challengesize);
- printf("make_challenge() rc=%d size=%d\n", rc, challengesize);
- if (rc) return rc;
- rc = hmac(secret, sizeof(secret), challenge, challengesize,
- &key, &keysize);
- printf("hmac(secret, challenge) rc=%d new_key_size=%d\n",
- rc, keysize);
- if (rc) return rc;
+ printf("using crypto %s\n", crypto_init(0));
+ ao = new_authobj(id, pass, nonce, secret, sizeof(secret),
+ payload, strlen((char *)payload));
+ printf("new_authobj err=%s\n", ao.err?ao.err:"<no error>");
+ printf("data(%d):", ao.datasize);
+ for (i = 0; i < ao.datasize; i++) printf(" %02x", ao.data[i]);
+ printf("\npayload(%d): \"%.*s\"\n", ao.paylsize, ao.paylsize,
+ ao.payload?(char*)ao.payload:"");
+ if (ao.err) {
+ if (ao.buffer) free(ao.buffer);
+ return 1;
+ }
- rc = parse_authobj(key, sizeof(key), authobj, authsize,
- newsecret, &newsecsize, newload, &newloadsize);
- printf("parse_authobj() rc=%d secretsize=%d payload=\"%.*s\" (%d)\n",
- rc, newsecsize, newloadsize, newload, newloadsize);
- if (memcmp(secret, newsecret, newsecsize)) {
- printf("extracted secret does not match\n");
- return -1;
+ nao = verify_authobj(id, pass, nonce, nonce, ao.data, ao.datasize);
+ printf("verify_authobj err=%s\n", nao.err?nao.err:"<no error>");
+ printf("data(%d):", nao.datasize);
+ for (i = 0; i < nao.datasize; i++) printf(" %02x", nao.data[i]);
+ printf("\npayload(%d): \"%.*s\"\n", nao.paylsize, nao.paylsize,
+ nao.payload?(char*)nao.payload:"");
+ if (nao.err) {
+ if (nao.buffer) free(nao.buffer);
+ return 1;
}
+ if (ao.paylsize != nao.paylsize ||
+ memcmp(ao.payload, nao.payload, ao.paylsize)) {
+ printf("payload does not match");
+ return 1;
+ }
+
+ if (ao.buffer) free(ao.buffer);
+ if (nao.buffer) free(nao.buffer);
return 0;
}