+/*
+Copyright (c) 2013 Eugene Crosser
+
+This software is provided 'as-is', without any express or implied
+warranty. In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+ 1. The origin of this software must not be misrepresented; you must
+ not claim that you wrote the original software. If you use this
+ software in a product, an acknowledgment in the product documentation
+ would be appreciated but is not required.
+
+ 2. Altered source versions must be plainly marked as such, and must
+ not be misrepresented as being the original software.
+
+ 3. This notice may not be removed or altered from any source
+ distribution.
+*/
+
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdio.h>
#include <string.h>
+#include <stdlib.h>
#include <alloca.h>
#include "serial.h"
#include "crypto.h"
#include "authobj.h"
-#include "pcsc_cr.h"
static struct _auth_chunk
make_challenge(const char *uid, const char *pass, const char *nonce)
}
static struct _auth_chunk
-make_key(const unsigned char *challenge, const int challengesize,
+new_key(const unsigned char *challenge, const int challengesize,
const unsigned char *secret, const int secsize)
{
struct _auth_chunk ho = {0};
return ho;
}
+static struct _auth_chunk
+make_key(const char *userid, const char *password, const char *nonce,
+ const unsigned char *secret, const int secsize,
+ struct _auth_chunk (*fetch_key)(const unsigned char *chal,
+ const int csize))
+{
+ struct _auth_chunk ho_chal, ho_key = {0};
+
+ if (!userid || !password || !nonce) {
+ ho_key.err = "make_key: missing uid, pass or nonce";
+ return ho_key;
+ }
+ ho_chal = make_challenge(userid, password, nonce);
+ if (ho_chal.err) {
+ ho_key.err = ho_chal.err;
+ return ho_key;
+ }
+ if (secret && secsize) {
+ ho_key = new_key(ho_chal.data, sizeof(ho_chal.data),
+ secret, secsize);
+ } else if (fetch_key) {
+ ho_key = (*fetch_key)(ho_chal.data, sizeof(ho_chal.data));
+ } else {
+ ho_key.err = "make_key: neither secret nor fetch_key present";
+ }
+ memset(&ho_chal, 0, sizeof(ho_chal));
+ return ho_key;
+}
+
static struct _auth_obj
-make_authobj(char *userid, char *password, char *nonce,
+make_authobj(const char *userid, const char *password, const char *nonce,
const unsigned char *secret, const int secsize,
const unsigned char *payload, const int paylsize)
{
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) /
+ datasize = ((secsize + paylsize + HASHSIZE + 4 * sizeof(short) - 1) /
CBLKSIZE + 1) * CBLKSIZE;
data = alloca(datasize);
+ /*
+ We allocate memory rounded up to CBLKSIZE on the stack, but do not
+ use the last bytes. Stack protectors, if enabled, fill this memory
+ with `canary` value. Later, when encryption function is called,
+ stack protector detects that it tries to access "uninitialized
+ memory". Which, while technically true, is not an error. Still,
+ let us make stack protector happy by initializing the whole area:
+ */
+ memset(data, 0, datasize);
serial_init(&srl, data, datasize);
if (serial_put(&srl, secret, secsize) != secsize) {
ao.err = "authobj: serialization of secret failed";
- } else if (serial_put(&srl, payload, paysize) != paysize) {
+ } else if (serial_put(&srl, payload, paylsize) != paylsize) {
ao.err = "authobj: serialization of payload failed";
} else if ((rc = hash(data, serial_size(&srl),
datahash, &datahashsize))) {
ao.err = "authobj: serialization of hash failed";
} else if (serial_put(&srl, NULL, 0) != 0) {
ao.err = "authobj: serialization of terminator failed";
- }
-
- if (!ao.err) {
+ } else {
unsigned long lrc;
int osize = ((serial_size(&srl) -1) / CBLKSIZE + 1) * CBLKSIZE;
+ struct _auth_chunk ho_key;
- if ((ao.buffer = malloc(osize + paysize)) == NULL) {
+ ho_key = make_key(userid, password, nonce,
+ secret, secsize, NULL);
+ if (ho_key.err) {
+ ao.err = ho_key.err;
+ } else if ((ao.buffer = malloc(osize + paylsize)) == NULL) {
ao.err = "make authobj: malloc failed";
- } else if ((lrc = encrypt(key, CBLKSIZE, data,
+ } else if ((lrc = encrypt(ho_key.data, CBLKSIZE, data,
ao.buffer, osize))) {
ao.err = crypto_errstr(lrc);
} else {
ao.data = ao.buffer;
ao.datasize = osize;
- if (payload && paysize) {
+ if (payload && paylsize) {
/* payload passthrough */
ao.payload = ao.data + osize;
- memcpy(ao.payload, payload, paysize);
- ao.paylsize = paysize;
+ memcpy(ao.payload, payload, paylsize);
+ ao.paylsize = paylsize;
}
}
+ memset(&ho_key, 0, sizeof(ho_key));
}
-
memset(data, 0, datasize);
return ao;
}
static struct _auth_obj
-parse_authobj(char *userid, char *password, char *nonce,
+parse_authobj(const char *userid, const char *password, const char *nonce,
const unsigned char *secret, const int secsize,
const unsigned char *ablob, const int blobsize,
struct _auth_chunk (*fetch_key)(const unsigned char *chal,
{
unsigned long rc;
struct _auth_obj ao = {0};
+ struct _auth_chunk ho_key;
- if (keysize < CBLKSIZE) {
- ao.err = "parse authobj: key too short";
- } else if ((ao.buffer = malloc(bufsize)) == NULL) {
+ ho_key = make_key(userid, password, nonce, secret, secsize, fetch_key);
+ if (ho_key.err) {
+ ao.err = ho_key.err;
+ } else if ((ao.buffer = malloc(blobsize)) == NULL) {
ao.err = "parse authobj: malloc failed";
- } else if ((rc = decrypt(key, CBLKSIZE, buffer, ao.buffer, bufsize))) {
+ } else if ((rc = decrypt(ho_key.data, CBLKSIZE,
+ ablob, ao.buffer, blobsize))) {
ao.err = crypto_errstr(rc);
} else {
serializer_t srl;
int theirhsize;
unsigned long rc;
- serial_init(&srl, ao.buffer, bufsize);
+ serial_init(&srl, ao.buffer, blobsize);
if (serial_get(&srl, (void**)&ao.data, &ao.datasize)) {
ao.err = "mismatch: impossible secret";
} else if (serial_get(&srl, (void**)&ao.payload, &ao.paylsize)) {
ao.err = "mismatch: different hash";
}
}
+ memset(&ho_key, 0, sizeof(ho_key));
return ao;
}
struct _auth_chunk (*fetch_key)(const unsigned char *chal,
const int csize))
{
- unsigned char *wsecret;
+ const unsigned char *wsecret;
int wsecsize;
- unsigned char *wpayload;
+ const unsigned char *wpayload;
int wpaylsize;
- struct _auth_obj old_ao;
+ struct _auth_obj old_ao = {0};
struct _auth_obj new_ao = {0};
if (!secret || !secsize || !payload) {
new_ao = make_authobj(userid, password, newnonce,
- wsecret, wsecsize, wpayload, wpaysize);
+ wsecret, wsecsize, wpayload, wpaylsize);
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;
}
-
-void dummy() {
- struct _auth_chunk ho_chal, ho_key;
-
- ho_chal = make_challenge(userid, password, oldnonce);
- if (ho_chal.err) {
- 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) {
- 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));
-
-}
projects / pam_pcsc_cr.git / blobdiff