configure.ac: remove sanitizer by default

[pam_pcsc_cr.git] / authobj.c

diff --git a/authobj.c b/authobj.c
index b402094df224cd13651227c15e47bb9184976343..7e3c2eddc1ae30b222a14e23896ca529bde9bd16 100644 (file)
--- a/authobj.c
+++ b/authobj.c
@@ -38,10 +38,10 @@ make_challenge(const char *uid, const char *pass, const char *nonce)
        struct _auth_chunk ho = {0};
        unsigned long rc;
        serializer_t srl;
-       int datasize = strlen(uid) + strlen(pass) + strlen(nonce) +
+       size_t datasize = strlen(uid) + strlen(pass) + strlen(nonce) +
                        4 * sizeof(short);
        unsigned char *data = alloca(datasize);
-       int hashsize = sizeof(ho.data);
+       size_t hashsize = sizeof(ho.data);
 
        serial_init(&srl, data, datasize);
        if (serial_put(&srl, uid, strlen(uid)) != strlen(uid)) {
@@ -65,12 +65,12 @@ make_challenge(const char *uid, const char *pass, const char *nonce)
 }
 
 static struct _auth_chunk
-new_key(const unsigned char *challenge, const int challengesize,
-       const unsigned char *secret, const int secsize)
+new_key(const unsigned char *challenge, const size_t challengesize,
+       const unsigned char *secret, const size_t secsize)
 {
        struct _auth_chunk ho = {0};
        unsigned long rc;
-       int keysize = sizeof(ho.data);
+       size_t keysize = sizeof(ho.data);
 
        if ((rc = hmac(secret, secsize, challenge, challengesize,
                        &ho.data, &keysize))) {
@@ -85,7 +85,7 @@ 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))
+                                       const size_t csize))
 {
        struct _auth_chunk ho_chal, ho_key = {0};
 
@@ -112,20 +112,29 @@ make_key(const char *userid, const char *password, const char *nonce,
 
 static struct _auth_obj
 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)
+               const unsigned char *secret, const size_t secsize,
+               const unsigned char *payload, const size_t paylsize)
 {
        struct _auth_obj ao = {0};
        unsigned long rc;
        unsigned char *data;
-       int datasize;
+       size_t datasize;
        unsigned char datahash[HASHSIZE];
-       int datahashsize = HASHSIZE;
+       size_t datahashsize = HASHSIZE;
        serializer_t srl;
 
        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";
@@ -173,7 +182,7 @@ 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,
-                                               const int csize))
+                                               const size_t csize))
 {
        unsigned long rc;
        struct _auth_obj ao = {0};
@@ -190,9 +199,9 @@ parse_authobj(const char *userid, const char *password, const char *nonce,
        } else {
                serializer_t srl;
                unsigned char myhash[HASHSIZE];
-               int myhsize = HASHSIZE;
+               size_t myhsize = HASHSIZE;
                unsigned char *theirhash;
-               int theirhsize;
+               size_t theirhsize;
                unsigned long rc;
 
                serial_init(&srl, ao.buffer, blobsize);
@@ -218,11 +227,11 @@ parse_authobj(const char *userid, const char *password, const char *nonce,
 
 struct _auth_obj authobj(const char *userid, const char *password,
                const char *oldnonce, const char *newnonce,
-               const unsigned char *secret, const int secsize,
-               const unsigned char *payload, const int paylsize,
-               const unsigned char *ablob, const int blobsize,
+               const unsigned char *secret, const size_t secsize,
+               const unsigned char *payload, const size_t paylsize,
+               const unsigned char *ablob, const size_t blobsize,
                struct _auth_chunk (*fetch_key)(const unsigned char *chal,
-                                               const int csize))
+                                               const size_t csize))
 {
        const unsigned char *wsecret;
        int wsecsize;
@@ -232,6 +241,10 @@ struct _auth_obj authobj(const char *userid, const char *password,
        struct _auth_obj new_ao = {0};
 
        if (!secret || !secsize || !payload) {
+               if (!ablob || !blobsize) {
+                       new_ao.err = "authobj: previous data not supplied";
+                       return new_ao;
+               }
                old_ao = parse_authobj(userid, password, oldnonce,
                                        secret, secsize,
                                        ablob, blobsize, fetch_key);