Fix double free bug in error path
[openssl.git] / crypto / dsa / dsa_lib.c
index e9b75902dbc25e21ab9565855c33ccdadbc1a272..facb97fb5ebb64571ba8dd7e20f209b5cea66f8c 100644 (file)
@@ -1,25 +1,24 @@
-/* crypto/dsa/dsa_lib.c */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
  * This package is an SSL implementation written
  * by Eric Young (eay@cryptsoft.com).
  * The implementation was written so as to conform with Netscapes SSL.
- * 
+ *
  * This library is free for commercial and non-commercial use as long as
  * the following conditions are aheared to.  The following conditions
  * apply to all code found in this distribution, be it the RC4, RSA,
  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  * included with this distribution is covered by the same copyright terms
  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
- * 
+ *
  * Copyright remains Eric Young's, and as such any Copyright notices in
  * the code are not to be removed.
  * If this package is used in a product, Eric Young should be given attribution
  * as the author of the parts of the library used.
  * This can be in the form of a textual message at program startup or
  * in documentation (online or textual) provided with the package.
- * 
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *     Eric Young (eay@cryptsoft.com)"
  *    The word 'cryptographic' can be left out if the rouines from the library
  *    being used are not cryptographic related :-).
- * 4. If you include any Windows specific code (or a derivative thereof) from 
+ * 4. If you include any Windows specific code (or a derivative thereof) from
  *    the apps directory (application code) you must include an acknowledgement:
  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
- * 
+ *
  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
@@ -49,7 +48,7 @@
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
- * 
+ *
  * The licence and distribution terms for any publically available version or
  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  * copied and put under another distribution licence
 /* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
 
 #include <stdio.h>
-#include "cryptlib.h"
+#include "internal/cryptlib.h"
 #include <openssl/bn.h>
-#include <openssl/dsa.h>
+#include "dsa_locl.h"
 #include <openssl/asn1.h>
-#ifndef OPENSSL_NO_ENGINE
 #include <openssl/engine.h>
-#endif
-#ifndef OPENSSL_NO_DH
 #include <openssl/dh.h>
-#endif
-
-const char DSA_version[]="DSA" OPENSSL_VERSION_PTEXT;
 
 static const DSA_METHOD *default_DSA_method = NULL;
 
 void DSA_set_default_method(const DSA_METHOD *meth)
-       {
-       default_DSA_method = meth;
-       }
+{
+    default_DSA_method = meth;
+}
 
 const DSA_METHOD *DSA_get_default_method(void)
-       {
-       if(!default_DSA_method)
-               default_DSA_method = DSA_OpenSSL();
-       return default_DSA_method;
-       }
+{
+    if (!default_DSA_method)
+        default_DSA_method = DSA_OpenSSL();
+    return default_DSA_method;
+}
 
 DSA *DSA_new(void)
-       {
-       return DSA_new_method(NULL);
-       }
+{
+    return DSA_new_method(NULL);
+}
 
 int DSA_set_method(DSA *dsa, const DSA_METHOD *meth)
-       {
-       /* NB: The caller is specifically setting a method, so it's not up to us
-        * to deal with which ENGINE it comes from. */
-        const DSA_METHOD *mtmp;
-        mtmp = dsa->meth;
-        if (mtmp->finish) mtmp->finish(dsa);
+{
+    /*
+     * NB: The caller is specifically setting a method, so it's not up to us
+     * to deal with which ENGINE it comes from.
+     */
+    const DSA_METHOD *mtmp;
+    mtmp = dsa->meth;
+    if (mtmp->finish)
+        mtmp->finish(dsa);
 #ifndef OPENSSL_NO_ENGINE
-       if (dsa->engine)
-               {
-               ENGINE_finish(dsa->engine);
-               dsa->engine = NULL;
-               }
+    ENGINE_finish(dsa->engine);
+    dsa->engine = NULL;
 #endif
-        dsa->meth = meth;
-        if (meth->init) meth->init(dsa);
-        return 1;
-       }
+    dsa->meth = meth;
+    if (meth->init)
+        meth->init(dsa);
+    return 1;
+}
+
+const DSA_METHOD *DSA_get_method(DSA *d)
+{
+    return d->meth;
+}
 
 DSA *DSA_new_method(ENGINE *engine)
-       {
-       DSA *ret;
-
-       ret=(DSA *)OPENSSL_malloc(sizeof(DSA));
-       if (ret == NULL)
-               {
-               DSAerr(DSA_F_DSA_NEW_METHOD,ERR_R_MALLOC_FAILURE);
-               return(NULL);
-               }
-       ret->meth = DSA_get_default_method();
+{
+    DSA *ret;
+
+    ret = OPENSSL_zalloc(sizeof(*ret));
+    if (ret == NULL) {
+        DSAerr(DSA_F_DSA_NEW_METHOD, ERR_R_MALLOC_FAILURE);
+        return NULL;
+    }
+    ret->meth = DSA_get_default_method();
 #ifndef OPENSSL_NO_ENGINE
-       if (engine)
-               {
-               if (!ENGINE_init(engine))
-                       {
-                       DSAerr(DSA_F_DSA_NEW_METHOD, ERR_R_ENGINE_LIB);
-                       OPENSSL_free(ret);
-                       return NULL;
-                       }
-               ret->engine = engine;
-               }
-       else
-               ret->engine = ENGINE_get_default_DSA();
-       if(ret->engine)
-               {
-               ret->meth = ENGINE_get_DSA(ret->engine);
-               if(!ret->meth)
-                       {
-                       DSAerr(DSA_F_DSA_NEW_METHOD,
-                               ERR_R_ENGINE_LIB);
-                       ENGINE_finish(ret->engine);
-                       OPENSSL_free(ret);
-                       return NULL;
-                       }
-               }
+    if (engine) {
+        if (!ENGINE_init(engine)) {
+            DSAerr(DSA_F_DSA_NEW_METHOD, ERR_R_ENGINE_LIB);
+            OPENSSL_free(ret);
+            return NULL;
+        }
+        ret->engine = engine;
+    } else
+        ret->engine = ENGINE_get_default_DSA();
+    if (ret->engine) {
+        ret->meth = ENGINE_get_DSA(ret->engine);
+        if (ret->meth == NULL) {
+            DSAerr(DSA_F_DSA_NEW_METHOD, ERR_R_ENGINE_LIB);
+            ENGINE_finish(ret->engine);
+            OPENSSL_free(ret);
+            return NULL;
+        }
+    }
 #endif
 
-       ret->pad=0;
-       ret->version=0;
-       ret->write_params=1;
-       ret->p=NULL;
-       ret->q=NULL;
-       ret->g=NULL;
-
-       ret->pub_key=NULL;
-       ret->priv_key=NULL;
-
-       ret->kinv=NULL;
-       ret->r=NULL;
-       ret->method_mont_p=NULL;
-
-       ret->references=1;
-       ret->flags=ret->meth->flags;
-       CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
-       if ((ret->meth->init != NULL) && !ret->meth->init(ret))
-               {
+    ret->references = 1;
+    ret->flags = ret->meth->flags & ~DSA_FLAG_NON_FIPS_ALLOW;
+
+    CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
+
+    ret->lock = CRYPTO_THREAD_lock_new();
+    if (ret->lock == NULL) {
 #ifndef OPENSSL_NO_ENGINE
-               if (ret->engine)
-                       ENGINE_finish(ret->engine);
+        ENGINE_finish(ret->engine);
 #endif
-               CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
-               OPENSSL_free(ret);
-               ret=NULL;
-               }
-       
-       return(ret);
-       }
+        CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
+        OPENSSL_free(ret);
+        return NULL;
+    }
+
+    if ((ret->meth->init != NULL) && !ret->meth->init(ret)) {
+        DSA_free(ret);
+        ret = NULL;
+    }
+
+    return ret;
+}
 
 void DSA_free(DSA *r)
-       {
-       int i;
+{
+    int i;
 
-       if (r == NULL) return;
+    if (r == NULL)
+        return;
 
-       i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_DSA);
-#ifdef REF_PRINT
-       REF_PRINT("DSA",r);
-#endif
-       if (i > 0) return;
-#ifdef REF_CHECK
-       if (i < 0)
-               {
-               fprintf(stderr,"DSA_free, bad reference count\n");
-               abort();
-               }
-#endif
+    CRYPTO_atomic_add(&r->references, -1, &i, r->lock);
+    REF_PRINT_COUNT("DSA", r);
+    if (i > 0)
+        return;
+    REF_ASSERT_ISNT(i < 0);
 
-       if(r->meth->finish)
-               r->meth->finish(r);
+    if (r->meth->finish)
+        r->meth->finish(r);
 #ifndef OPENSSL_NO_ENGINE
-       if(r->engine)
-               ENGINE_finish(r->engine);
+    ENGINE_finish(r->engine);
 #endif
 
-       CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, r, &r->ex_data);
+    CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, r, &r->ex_data);
 
-       if (r->p != NULL) BN_clear_free(r->p);
-       if (r->q != NULL) BN_clear_free(r->q);
-       if (r->g != NULL) BN_clear_free(r->g);
-       if (r->pub_key != NULL) BN_clear_free(r->pub_key);
-       if (r->priv_key != NULL) BN_clear_free(r->priv_key);
-       if (r->kinv != NULL) BN_clear_free(r->kinv);
-       if (r->r != NULL) BN_clear_free(r->r);
-       OPENSSL_free(r);
-       }
+    CRYPTO_THREAD_lock_free(r->lock);
+
+    BN_clear_free(r->p);
+    BN_clear_free(r->q);
+    BN_clear_free(r->g);
+    BN_clear_free(r->pub_key);
+    BN_clear_free(r->priv_key);
+    OPENSSL_free(r);
+}
 
 int DSA_up_ref(DSA *r)
-       {
-       int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DSA);
-#ifdef REF_PRINT
-       REF_PRINT("DSA",r);
-#endif
-#ifdef REF_CHECK
-       if (i < 2)
-               {
-               fprintf(stderr, "DSA_up_ref, bad reference count\n");
-               abort();
-               }
-#endif
-       return ((i > 1) ? 1 : 0);
-       }
+{
+    int i;
+
+    if (CRYPTO_atomic_add(&r->references, 1, &i, r->lock) <= 0)
+        return 0;
+
+    REF_PRINT_COUNT("DSA", r);
+    REF_ASSERT_ISNT(i < 2);
+    return ((i > 1) ? 1 : 0);
+}
 
 int DSA_size(const DSA *r)
-       {
-       int ret,i;
-       ASN1_INTEGER bs;
-       unsigned char buf[4];   /* 4 bytes looks really small.
-                                  However, i2d_ASN1_INTEGER() will not look
-                                  beyond the first byte, as long as the second
-                                  parameter is NULL. */
-
-       i=BN_num_bits(r->q);
-       bs.length=(i+7)/8;
-       bs.data=buf;
-       bs.type=V_ASN1_INTEGER;
-       /* If the top bit is set the asn1 encoding is 1 larger. */
-       buf[0]=0xff;    
-
-       i=i2d_ASN1_INTEGER(&bs,NULL);
-       i+=i; /* r and s */
-       ret=ASN1_object_size(1,i,V_ASN1_SEQUENCE);
-       return(ret);
-       }
-
-int DSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
-            CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
-        {
-       return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DSA, argl, argp,
-                               new_func, dup_func, free_func);
-        }
+{
+    int ret, i;
+    ASN1_INTEGER bs;
+    unsigned char buf[4];       /* 4 bytes looks really small. However,
+                                 * i2d_ASN1_INTEGER() will not look beyond
+                                 * the first byte, as long as the second
+                                 * parameter is NULL. */
+
+    i = BN_num_bits(r->q);
+    bs.length = (i + 7) / 8;
+    bs.data = buf;
+    bs.type = V_ASN1_INTEGER;
+    /* If the top bit is set the asn1 encoding is 1 larger. */
+    buf[0] = 0xff;
+
+    i = i2d_ASN1_INTEGER(&bs, NULL);
+    i += i;                     /* r and s */
+    ret = ASN1_object_size(1, i, V_ASN1_SEQUENCE);
+    return (ret);
+}
 
 int DSA_set_ex_data(DSA *d, int idx, void *arg)
-       {
-       return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));
-       }
+{
+    return (CRYPTO_set_ex_data(&d->ex_data, idx, arg));
+}
 
 void *DSA_get_ex_data(DSA *d, int idx)
-       {
-       return(CRYPTO_get_ex_data(&d->ex_data,idx));
-       }
+{
+    return (CRYPTO_get_ex_data(&d->ex_data, idx));
+}
+
+int DSA_security_bits(const DSA *d)
+{
+    if (d->p && d->q)
+        return BN_security_bits(BN_num_bits(d->p), BN_num_bits(d->q));
+    return -1;
+}
 
 #ifndef OPENSSL_NO_DH
 DH *DSA_dup_DH(const DSA *r)
-       {
-       /* DSA has p, q, g, optional pub_key, optional priv_key.
-        * DH has p, optional length, g, optional pub_key, optional priv_key.
-        */ 
-
-       DH *ret = NULL;
-
-       if (r == NULL)
-               goto err;
-       ret = DH_new();
-       if (ret == NULL)
-               goto err;
-       if (r->p != NULL) 
-               if ((ret->p = BN_dup(r->p)) == NULL)
-                       goto err;
-       if (r->q != NULL)
-               ret->length = BN_num_bits(r->q);
-       if (r->g != NULL)
-               if ((ret->g = BN_dup(r->g)) == NULL)
-                       goto err;
-       if (r->pub_key != NULL)
-               if ((ret->pub_key = BN_dup(r->pub_key)) == NULL)
-                       goto err;
-       if (r->priv_key != NULL)
-               if ((ret->priv_key = BN_dup(r->priv_key)) == NULL)
-                       goto err;
-
-       return ret;
+{
+    /*
+     * DSA has p, q, g, optional pub_key, optional priv_key. DH has p,
+     * optional length, g, optional pub_key, optional priv_key, optional q.
+     */
+
+    DH *ret = NULL;
+    BIGNUM *p = NULL, *q = NULL, *g = NULL, *pub_key = NULL, *priv_key = NULL;
+
+    if (r == NULL)
+        goto err;
+    ret = DH_new();
+    if (ret == NULL)
+        goto err;
+    if (r->p != NULL || r->g != NULL || r->q != NULL) {
+        if (r->p == NULL || r->g == NULL || r->q == NULL) {
+            /* Shouldn't happen */
+            goto err;
+        }
+        p = BN_dup(r->p);
+        g = BN_dup(r->g);
+        q = BN_dup(r->q);
+        if (p == NULL || g == NULL || q == NULL || !DH_set0_pqg(ret, p, q, g))
+            goto err;
+        p = g = q = NULL;
+    }
+
+    if (r->pub_key != NULL) {
+        pub_key = BN_dup(r->pub_key);
+        if (pub_key == NULL)
+            goto err;
+        if (r->priv_key != NULL) {
+            priv_key = BN_dup(r->priv_key);
+            if (priv_key == NULL)
+                goto err;
+        }
+        if (!DH_set0_key(ret, pub_key, priv_key))
+            goto err;
+    } else if (r->priv_key != NULL) {
+        /* Shouldn't happen */
+        goto err;
+    }
+
+    return ret;
 
  err:
-       if (ret != NULL)
-               DH_free(ret);
-       return NULL;
-       }
+    BN_free(p);
+    BN_free(g);
+    BN_free(q);
+    BN_free(pub_key);
+    BN_free(priv_key);
+    DH_free(ret);
+    return NULL;
+}
 #endif
+
+void DSA_get0_pqg(const DSA *d, BIGNUM **p, BIGNUM **q, BIGNUM **g)
+{
+    if (p != NULL)
+        *p = d->p;
+    if (q != NULL)
+        *q = d->q;
+    if (g != NULL)
+        *g = d->g;
+}
+
+int DSA_set0_pqg(DSA *d, BIGNUM *p, BIGNUM *q, BIGNUM *g)
+{
+    if (p == NULL || q == NULL || g == NULL)
+        return 0;
+    BN_free(d->p);
+    BN_free(d->q);
+    BN_free(d->g);
+    d->p = p;
+    d->q = q;
+    d->g = g;
+
+    return 1;
+}
+
+void DSA_get0_key(const DSA *d, BIGNUM **pub_key, BIGNUM **priv_key)
+{
+    if (pub_key != NULL)
+        *pub_key = d->pub_key;
+    if (priv_key != NULL)
+        *priv_key = d->priv_key;
+}
+
+int DSA_set0_key(DSA *d, BIGNUM *pub_key, BIGNUM *priv_key)
+{
+    /* Note that it is valid for priv_key to be NULL */
+    if (pub_key == NULL)
+        return 0;
+
+    BN_free(d->pub_key);
+    BN_free(d->priv_key);
+    d->pub_key = pub_key;
+    d->priv_key = priv_key;
+
+    return 1;
+}
+
+void DSA_clear_flags(DSA *d, int flags)
+{
+    d->flags &= ~flags;
+}
+
+int DSA_test_flags(const DSA *d, int flags)
+{
+    return d->flags & flags;
+}
+
+void DSA_set_flags(DSA *d, int flags)
+{
+    d->flags |= flags;
+}
+
+ENGINE *DSA_get0_engine(DSA *d)
+{
+    return d->engine;
+}