update for the cswift engine:

- fix the problem described in bug report 825
- fix a segfault when the engine fails to initialize
- let the engine switch to software when keysize > 2048

PR: 825, 826
Submitted by: Frédéric Giudicelli

diff --git a/engines/e_cswift.c b/engines/e_cswift.c
index f86c0573a8fc78a7efdfe74c4a4a3b314301e57a..56a19674962b45126bdfbeaaeaf790ed190930cd 100644 (file)
--- a/engines/e_cswift.c
+++ b/engines/e_cswift.c
@@ -98,6 +98,7 @@ static int cswift_destroy(ENGINE *e);
 static int cswift_init(ENGINE *e);
 static int cswift_finish(ENGINE *e);
 static int cswift_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void));
+static int cswift_bn_32copy(SW_LARGENUMBER * out, const BIGNUM * in);
 
 /* BIGNUM stuff */
 static int cswift_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
@@ -415,7 +416,10 @@ static int cswift_init(ENGINE *e)
        return 1;
 err:
        if(cswift_dso)
+       {
                DSO_free(cswift_dso);
+               cswift_dso = NULL;
+       }
        p_CSwift_AcquireAccContext = NULL;
        p_CSwift_AttachKeyParam = NULL;
        p_CSwift_SimpleRequest = NULL;
@@ -565,6 +569,29 @@ err:
        return to_return;
        }
 
+
+int cswift_bn_32copy(SW_LARGENUMBER * out, const BIGNUM * in)
+{
+       int mod;
+       int numbytes = BN_num_bytes(in);
+
+       mod = 0;
+       while( ((out->nbytes = (numbytes+mod)) % 32) )
+       {
+               mod++;
+       }
+       out->value = (unsigned char*)OPENSSL_malloc(out->nbytes);
+       if(!out->value)
+       {
+               return 0;
+       }
+       BN_bn2bin(in, &out->value[mod]);
+       if(mod)
+               memset(out->value, 0, mod);
+
+       return 1;
+}
+
 /* Un petit mod_exp chinois */
 static int cswift_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                        const BIGNUM *q, const BIGNUM *dmp1,
@@ -574,15 +601,16 @@ static int cswift_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
        SW_LARGENUMBER arg, res;
        SW_PARAM sw_param;
        SW_CONTEXT_HANDLE hac;
-       BIGNUM *rsa_p = NULL;
-       BIGNUM *rsa_q = NULL;
-       BIGNUM *rsa_dmp1 = NULL;
-       BIGNUM *rsa_dmq1 = NULL;
-       BIGNUM *rsa_iqmp = NULL;
-       BIGNUM *argument = NULL;
        BIGNUM *result = NULL;
+       BIGNUM *argument = NULL;
        int to_return = 0; /* expect failure */
        int acquired = 0;
+
+       sw_param.up.crt.p.value = NULL;
+       sw_param.up.crt.q.value = NULL;
+       sw_param.up.crt.dmp1.value = NULL;
+       sw_param.up.crt.dmq1.value = NULL;
+       sw_param.up.crt.iqmp.value = NULL;
  
        if(!get_context(&hac))
                {
@@ -590,44 +618,55 @@ static int cswift_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                goto err;
                }
        acquired = 1;
+
        /* Prepare the params */
-       BN_CTX_start(ctx);
-       rsa_p = BN_CTX_get(ctx);
-       rsa_q = BN_CTX_get(ctx);
-       rsa_dmp1 = BN_CTX_get(ctx);
-       rsa_dmq1 = BN_CTX_get(ctx);
-       rsa_iqmp = BN_CTX_get(ctx);
-       argument = BN_CTX_get(ctx);
-       result = BN_CTX_get(ctx);
-       if(!result)
+       argument = BN_new();
+       result = BN_new();
+       if(!result || !argument)
                {
                CSWIFTerr(CSWIFT_F_CSWIFT_MOD_EXP_CRT,CSWIFT_R_BN_CTX_FULL);
                goto err;
                }
-       if(!bn_wexpand(rsa_p, p->top) || !bn_wexpand(rsa_q, q->top) ||
-                       !bn_wexpand(rsa_dmp1, dmp1->top) ||
-                       !bn_wexpand(rsa_dmq1, dmq1->top) ||
-                       !bn_wexpand(rsa_iqmp, iqmp->top) ||
-                       !bn_wexpand(argument, a->top) ||
+
+
+       sw_param.type = SW_ALG_CRT;
+       /************************************************************************/
+       /* 04/02/2003                                                           */
+       /* Modified by Frederic Giudicelli (deny-all.com) to overcome the       */
+       /* limitation of cswift with values not a multiple of 32                */
+       /************************************************************************/
+       if(!cswift_bn_32copy(&sw_param.up.crt.p, p))
+       {
+               CSWIFTerr(CSWIFT_F_CSWIFT_MOD_EXP_CRT,CSWIFT_R_BN_EXPAND_FAIL);
+               goto err;
+       }
+       if(!cswift_bn_32copy(&sw_param.up.crt.q, q))
+       {
+               CSWIFTerr(CSWIFT_F_CSWIFT_MOD_EXP_CRT,CSWIFT_R_BN_EXPAND_FAIL);
+               goto err;
+       }
+       if(!cswift_bn_32copy(&sw_param.up.crt.dmp1, dmp1))
+       {
+               CSWIFTerr(CSWIFT_F_CSWIFT_MOD_EXP_CRT,CSWIFT_R_BN_EXPAND_FAIL);
+               goto err;
+       }
+       if(!cswift_bn_32copy(&sw_param.up.crt.dmq1, dmq1))
+       {
+               CSWIFTerr(CSWIFT_F_CSWIFT_MOD_EXP_CRT,CSWIFT_R_BN_EXPAND_FAIL);
+               goto err;
+       }
+       if(!cswift_bn_32copy(&sw_param.up.crt.iqmp, iqmp))
+       {
+               CSWIFTerr(CSWIFT_F_CSWIFT_MOD_EXP_CRT,CSWIFT_R_BN_EXPAND_FAIL);
+               goto err;
+       }
+       if(     !bn_wexpand(argument, a->top) ||
                        !bn_wexpand(result, p->top + q->top))
                {
                CSWIFTerr(CSWIFT_F_CSWIFT_MOD_EXP_CRT,CSWIFT_R_BN_EXPAND_FAIL);
                goto err;
                }
-       sw_param.type = SW_ALG_CRT;
-       sw_param.up.crt.p.nbytes = BN_bn2bin(p, (unsigned char *)rsa_p->d);
-       sw_param.up.crt.p.value = (unsigned char *)rsa_p->d;
-       sw_param.up.crt.q.nbytes = BN_bn2bin(q, (unsigned char *)rsa_q->d);
-       sw_param.up.crt.q.value = (unsigned char *)rsa_q->d;
-       sw_param.up.crt.dmp1.nbytes = BN_bn2bin(dmp1,
-               (unsigned char *)rsa_dmp1->d);
-       sw_param.up.crt.dmp1.value = (unsigned char *)rsa_dmp1->d;
-       sw_param.up.crt.dmq1.nbytes = BN_bn2bin(dmq1,
-               (unsigned char *)rsa_dmq1->d);
-       sw_param.up.crt.dmq1.value = (unsigned char *)rsa_dmq1->d;
-       sw_param.up.crt.iqmp.nbytes = BN_bn2bin(iqmp,
-               (unsigned char *)rsa_iqmp->d);
-       sw_param.up.crt.iqmp.value = (unsigned char *)rsa_iqmp->d;
+
        /* Attach the key params */
        sw_status = p_CSwift_AttachKeyParam(hac, &sw_param);
        switch(sw_status)
@@ -666,9 +705,22 @@ static int cswift_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
        BN_bin2bn((unsigned char *)result->d, res.nbytes, r);
        to_return = 1;
 err:
+       if(sw_param.up.crt.p.value)
+               OPENSSL_free(sw_param.up.crt.p.value);
+       if(sw_param.up.crt.q.value)
+               OPENSSL_free(sw_param.up.crt.q.value);
+       if(sw_param.up.crt.dmp1.value)
+               OPENSSL_free(sw_param.up.crt.dmp1.value);
+       if(sw_param.up.crt.dmq1.value)
+               OPENSSL_free(sw_param.up.crt.dmq1.value);
+       if(sw_param.up.crt.iqmp.value)
+               OPENSSL_free(sw_param.up.crt.iqmp.value);
+       if(result)
+               BN_free(result);
+       if(argument)
+               BN_free(argument);
        if(acquired)
                release_context(hac);
-       BN_CTX_end(ctx);
        return to_return;
        }
  
@@ -676,6 +728,27 @@ err:
 static int cswift_rsa_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
        {
        int to_return = 0;
+       const RSA_METHOD * def_rsa_method;
+
+       /* Try the limits of RSA (2048 bits) */
+       if(BN_num_bytes(rsa->p) > 128 ||
+               BN_num_bytes(rsa->q) > 128 ||
+               BN_num_bytes(rsa->dmp1) > 128 ||
+               BN_num_bytes(rsa->dmq1) > 128 ||
+               BN_num_bytes(rsa->iqmp) > 128)
+       {
+#ifdef RSA_NULL
+               def_rsa_method=RSA_null_method();
+#else
+#if 0
+               def_rsa_method=RSA_PKCS1_RSAref();
+#else
+               def_rsa_method=RSA_PKCS1_SSLeay();
+#endif
+#endif
+               if(def_rsa_method)
+                       return def_rsa_method->rsa_mod_exp(r0, I, rsa, ctx);
+       }
 
        if(!rsa->p || !rsa->q || !rsa->dmp1 || !rsa->dmq1 || !rsa->iqmp)
                {
@@ -693,6 +766,26 @@ err:
 static int cswift_mod_exp_mont(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx)
        {
+       const RSA_METHOD * def_rsa_method;
+
+       /* Try the limits of RSA (2048 bits) */
+       if(BN_num_bytes(r) > 256 ||
+               BN_num_bytes(a) > 256 ||
+               BN_num_bytes(m) > 256)
+       {
+#ifdef RSA_NULL
+               def_rsa_method=RSA_null_method();
+#else
+#if 0
+               def_rsa_method=RSA_PKCS1_RSAref();
+#else
+               def_rsa_method=RSA_PKCS1_SSLeay();
+#endif
+#endif
+               if(def_rsa_method)
+                       return def_rsa_method->bn_mod_exp(r, a, p, m, ctx, m_ctx);
+       }
+
        return cswift_mod_exp(r, a, p, m, ctx);
        }
 
@@ -937,9 +1030,10 @@ static int cswift_rand_bytes(unsigned char *buf, int num)
        SW_CONTEXT_HANDLE hac;
        SW_STATUS swrc;
        SW_LARGENUMBER largenum;
-       size_t nbytes = 0;
        int acquired = 0;
        int to_return = 0; /* assume failure */
+       unsigned char buf32[1024];
+
 
        if (!get_context(&hac))
        {
@@ -948,17 +1042,19 @@ static int cswift_rand_bytes(unsigned char *buf, int num)
        }
        acquired = 1;
 
-       while (nbytes < (size_t)num)
+       /************************************************************************/
+       /* 04/02/2003                                                           */
+       /* Modified by Frederic Giudicelli (deny-all.com) to overcome the       */
+       /* limitation of cswift with values not a multiple of 32                */
+       /************************************************************************/
+
+       while(num >= sizeof(buf32))
        {
+               largenum.value = buf;
+               largenum.nbytes = sizeof(buf32);
                /* tell CryptoSwift how many bytes we want and where we want it.
                 * Note: - CryptoSwift cannot do more than 4096 bytes at a time.
                 *       - CryptoSwift can only do multiple of 32-bits. */
-               largenum.value = (SW_BYTE *) buf + nbytes;
-               if (4096 > num - nbytes)
-                       largenum.nbytes = num - nbytes;
-               else
-                       largenum.nbytes = 4096;
-
                swrc = p_CSwift_SimpleRequest(hac, SW_CMD_RAND, NULL, 0, &largenum, 1);
                if (swrc != SW_OK)
                {
@@ -968,14 +1064,30 @@ static int cswift_rand_bytes(unsigned char *buf, int num)
                        ERR_add_error_data(2, "CryptoSwift error number is ", tmpbuf);
                        goto err;
                }
-
-               nbytes += largenum.nbytes;
+               buf += sizeof(buf32);
+               num -= sizeof(buf32);
+       }
+       if(num)
+       {
+               largenum.nbytes = sizeof(buf32);
+               largenum.value = buf32;
+               swrc = p_CSwift_SimpleRequest(hac, SW_CMD_RAND, NULL, 0, &largenum, 1);
+               if (swrc != SW_OK)
+               {
+                       char tmpbuf[20];
+                       CSWIFTerr(CSWIFT_F_CSWIFT_CTRL, CSWIFT_R_REQUEST_FAILED);
+                       sprintf(tmpbuf, "%ld", swrc);
+                       ERR_add_error_data(2, "CryptoSwift error number is ", tmpbuf);
+                       goto err;
+               }
+               memcpy(buf, largenum.value, num);
        }
-       to_return = 1;  /* success */
 
+       to_return = 1;  /* success */
 err:
        if (acquired)
                release_context(hac);
+
        return to_return;
 }