Add new sign and verify members to RSA_METHOD and change SSL code to use sign
authorDr. Stephen Henson <steve@openssl.org>
Sat, 18 Sep 1999 22:37:44 +0000 (22:37 +0000)
committerDr. Stephen Henson <steve@openssl.org>
Sat, 18 Sep 1999 22:37:44 +0000 (22:37 +0000)
and verify rather than direct encrypt/decrypt.

CHANGES
crypto/rsa/rsa.h
crypto/rsa/rsa_err.c
crypto/rsa/rsa_sign.c
ssl/s3_clnt.c
ssl/s3_srvr.c

diff --git a/CHANGES b/CHANGES
index 7b9cf1c..6deb18f 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -4,6 +4,17 @@
 
  Changes between 0.9.4 and 0.9.5  [xx XXX 1999]
 
+  *) Enhance RSA_METHOD structure. Now there are two extra methods, rsa_sign
+     and rsa_verify. When the RSA_FLAGS_SIGN_VER option is set these functions
+     will be called when RSA_sign() and RSA_verify() are used. This is useful
+     if rsa_pub_dec() and rsa_priv_enc() equivalents are not available.
+     For this to work properly RSA_public_decrypt() and RSA_private_encrypt()
+     should *not* be used: RSA_sign() and RSA_verify() must be used instead.
+     This necessitated the support of an extra signature type NID_md5_sha1
+     for SSL signatures and modifications to the SSL library to use it instead
+     of calling RSA_public_decrypt() and RSA_private_encrypt().
+     [Steve Henson]
+
   *) Add new -verify -CAfile and -CApath options to the crl program, these
      will lookup a CRL issuers certificate and verify the signature in a
      similar way to the verify program. Tidy up the crl program so it
index 6c64db7..7fe1d23 100644 (file)
@@ -91,6 +91,18 @@ typedef struct rsa_meth_st
        int (*finish)(RSA *rsa);        /* called at free */
        int flags;                      /* RSA_METHOD_FLAG_* things */
        char *app_data;                 /* may be needed! */
+/* New sign and verify functions: some libraries don't allow arbitrary data
+ * to be signed/verified: this allows them to be used. Note: for this to work
+ * the RSA_public_decrypt() and RSA_private_encrypt() should *NOT* be used
+ * RSA_sign(), RSA_verify() should be used instead. Note: for backwards
+ * compatability this functionality is only enabled if the RSA_FLAG_SIGN_VER
+ * option is set in 'flags'.
+ */
+       int (*rsa_sign)(int type, unsigned char *m, unsigned int m_len,
+             unsigned char *sigret, unsigned int *siglen, RSA *rsa);
+       int (*rsa_verify)(int dtype, unsigned char *m, unsigned int m_len,
+             unsigned char *sigbuf, unsigned int siglen, RSA *rsa);
+
        } RSA_METHOD;
 
 struct rsa_st
@@ -140,6 +152,10 @@ struct rsa_st
  */
 #define RSA_FLAG_EXT_PKEY              0x20
 
+/* This flag in the RSA_METHOD enables the new rsa_sign, rsa_verify functions.
+ */
+#define RSA_FLAG_SIGN_VER              0x40
+
 #define RSA_PKCS1_PADDING      1
 #define RSA_SSLV23_PADDING     2
 #define RSA_NO_PADDING         3
@@ -299,6 +315,7 @@ char *RSA_get_ex_data(RSA *r, int idx);
 #define RSA_R_DMP1_NOT_CONGRUENT_TO_D                   124
 #define RSA_R_DMQ1_NOT_CONGRUENT_TO_D                   125
 #define RSA_R_D_E_NOT_CONGRUENT_TO_1                    123
+#define RSA_R_INVALID_MESSAGE_LENGTH                    131
 #define RSA_R_IQMP_NOT_INVERSE_OF_Q                     126
 #define RSA_R_KEY_SIZE_TOO_SMALL                        120
 #define RSA_R_NULL_BEFORE_BLOCK_MISSING                         113
index 7762bd5..5cfbea2 100644 (file)
@@ -111,6 +111,7 @@ static ERR_STRING_DATA RSA_str_reasons[]=
 {RSA_R_DMP1_NOT_CONGRUENT_TO_D           ,"dmp1 not congruent to d"},
 {RSA_R_DMQ1_NOT_CONGRUENT_TO_D           ,"dmq1 not congruent to d"},
 {RSA_R_D_E_NOT_CONGRUENT_TO_1            ,"d e not congruent to 1"},
+{RSA_R_INVALID_MESSAGE_LENGTH            ,"invalid message length"},
 {RSA_R_IQMP_NOT_INVERSE_OF_Q             ,"iqmp not inverse of q"},
 {RSA_R_KEY_SIZE_TOO_SMALL                ,"key size too small"},
 {RSA_R_NULL_BEFORE_BLOCK_MISSING         ,"null before block missing"},
index 1740494..15c6d1a 100644 (file)
 #include <openssl/objects.h>
 #include <openssl/x509.h>
 
+/* Size of an SSL signature: MD5+SHA1 */
+#define SSL_SIG_LENGTH 36
+
 int RSA_sign(int type, unsigned char *m, unsigned int m_len,
             unsigned char *sigret, unsigned int *siglen, RSA *rsa)
        {
        X509_SIG sig;
        ASN1_TYPE parameter;
        int i,j,ret=1;
-       unsigned char *p,*s;
+       unsigned char *p,*s = NULL;
        X509_ALGOR algor;
        ASN1_OCTET_STRING digest;
-
-       sig.algor= &algor;
-       sig.algor->algorithm=OBJ_nid2obj(type);
-       if (sig.algor->algorithm == NULL)
-               {
-               RSAerr(RSA_F_RSA_SIGN,RSA_R_UNKNOWN_ALGORITHM_TYPE);
-               return(0);
-               }
-       if (sig.algor->algorithm->length == 0)
-               {
-               RSAerr(RSA_F_RSA_SIGN,RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
-               return(0);
+       if(rsa->flags & RSA_FLAG_SIGN_VER)
+             return rsa->meth->rsa_sign(type, m, m_len, sigret, siglen, rsa);
+       /* Special case: SSL signature, just check the length */
+       if(type == NID_md5_sha1) {
+               if(m_len != SSL_SIG_LENGTH) {
+                       RSAerr(RSA_F_RSA_SIGN,RSA_R_INVALID_MESSAGE_LENGTH);
+                       return(0);
                }
-       parameter.type=V_ASN1_NULL;
-       parameter.value.ptr=NULL;
-       sig.algor->parameter= &parameter;
+               i = SSL_SIG_LENGTH;
+               s = m;
+       } else {
+               sig.algor= &algor;
+               sig.algor->algorithm=OBJ_nid2obj(type);
+               if (sig.algor->algorithm == NULL)
+                       {
+                       RSAerr(RSA_F_RSA_SIGN,RSA_R_UNKNOWN_ALGORITHM_TYPE);
+                       return(0);
+                       }
+               if (sig.algor->algorithm->length == 0)
+                       {
+                       RSAerr(RSA_F_RSA_SIGN,RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
+                       return(0);
+                       }
+               parameter.type=V_ASN1_NULL;
+               parameter.value.ptr=NULL;
+               sig.algor->parameter= &parameter;
 
-       sig.digest= &digest;
-       sig.digest->data=m;
-       sig.digest->length=m_len;
+               sig.digest= &digest;
+               sig.digest->data=m;
+               sig.digest->length=m_len;
 
-       i=i2d_X509_SIG(&sig,NULL);
+               i=i2d_X509_SIG(&sig,NULL);
+       }
        j=RSA_size(rsa);
        if ((i-RSA_PKCS1_PADDING) > j)
                {
                RSAerr(RSA_F_RSA_SIGN,RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);
                return(0);
                }
-       s=(unsigned char *)Malloc((unsigned int)j+1);
-       if (s == NULL)
-               {
-               RSAerr(RSA_F_RSA_SIGN,ERR_R_MALLOC_FAILURE);
-               return(0);
-               }
-       p=s;
-       i2d_X509_SIG(&sig,&p);
+       if(type != NID_md5_sha1) {
+               s=(unsigned char *)Malloc((unsigned int)j+1);
+               if (s == NULL)
+                       {
+                       RSAerr(RSA_F_RSA_SIGN,ERR_R_MALLOC_FAILURE);
+                       return(0);
+                       }
+               p=s;
+               i2d_X509_SIG(&sig,&p);
+       }
        i=RSA_private_encrypt(i,s,sigret,rsa,RSA_PKCS1_PADDING);
        if (i <= 0)
                ret=0;
        else
                *siglen=i;
 
-       memset(s,0,(unsigned int)j+1);
-       Free(s);
+       if(type != NID_md5_sha1) {
+               memset(s,0,(unsigned int)j+1);
+               Free(s);
+       }
        return(ret);
        }
 
@@ -132,53 +150,68 @@ int RSA_verify(int dtype, unsigned char *m, unsigned int m_len,
                return(0);
                }
 
+       if(rsa->flags & RSA_FLAG_SIGN_VER)
+           return rsa->meth->rsa_verify(dtype, m, m_len, sigbuf, siglen, rsa);
+
        s=(unsigned char *)Malloc((unsigned int)siglen);
        if (s == NULL)
                {
                RSAerr(RSA_F_RSA_VERIFY,ERR_R_MALLOC_FAILURE);
                goto err;
                }
+       if((dtype == NID_md5_sha1) && (m_len != SSL_SIG_LENGTH) ) {
+                       RSAerr(RSA_F_RSA_VERIFY,RSA_R_INVALID_MESSAGE_LENGTH);
+                       return(0);
+       }
        i=RSA_public_decrypt((int)siglen,sigbuf,s,rsa,RSA_PKCS1_PADDING);
 
        if (i <= 0) goto err;
 
-       p=s;
-       sig=d2i_X509_SIG(NULL,&p,(long)i);
+       /* Special case: SSL signature */
+       if(dtype == NID_md5_sha1) {
+               if((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH))
+                               RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
+               else ret = 1;
+       } else {
+               p=s;
+               sig=d2i_X509_SIG(NULL,&p,(long)i);
 
-       if (sig == NULL) goto err;
-       sigtype=OBJ_obj2nid(sig->algor->algorithm);
+               if (sig == NULL) goto err;
+               sigtype=OBJ_obj2nid(sig->algor->algorithm);
 
 
-#ifdef RSA_DEBUG
-       /* put a backward compatability flag in EAY */
-       fprintf(stderr,"in(%s) expect(%s)\n",OBJ_nid2ln(sigtype),
-               OBJ_nid2ln(dtype));
-#endif
-       if (sigtype != dtype)
-               {
-               if (((dtype == NID_md5) &&
-                       (sigtype == NID_md5WithRSAEncryption)) ||
-                       ((dtype == NID_md2) &&
-                       (sigtype == NID_md2WithRSAEncryption)))
+       #ifdef RSA_DEBUG
+               /* put a backward compatability flag in EAY */
+               fprintf(stderr,"in(%s) expect(%s)\n",OBJ_nid2ln(sigtype),
+                       OBJ_nid2ln(dtype));
+       #endif
+               if (sigtype != dtype)
                        {
-                       /* ok, we will let it through */
-#if !defined(NO_STDIO) && !defined(WIN16)
-                       fprintf(stderr,"signature has problems, re-make with post SSLeay045\n");
-#endif
+                       if (((dtype == NID_md5) &&
+                               (sigtype == NID_md5WithRSAEncryption)) ||
+                               ((dtype == NID_md2) &&
+                               (sigtype == NID_md2WithRSAEncryption)))
+                               {
+                               /* ok, we will let it through */
+       #if !defined(NO_STDIO) && !defined(WIN16)
+                               fprintf(stderr,"signature has problems, re-make with post SSLeay045\n");
+       #endif
+                               }
+                       else
+                               {
+                               RSAerr(RSA_F_RSA_VERIFY,
+                                               RSA_R_ALGORITHM_MISMATCH);
+                               goto err;
+                               }
                        }
-               else
+               if (    ((unsigned int)sig->digest->length != m_len) ||
+                       (memcmp(m,sig->digest->data,m_len) != 0))
                        {
-                       RSAerr(RSA_F_RSA_VERIFY,RSA_R_ALGORITHM_MISMATCH);
-                       goto err;
+                       RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
                        }
-               }
-       if (    ((unsigned int)sig->digest->length != m_len) ||
-               (memcmp(m,sig->digest->data,m_len) != 0))
-               {
-               RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
-               }
-       else
-               ret=1;
+               else
+                       ret=1;
+       }
 err:
        if (sig != NULL) X509_SIG_free(sig);
        memset(s,0,(unsigned int)siglen);
index d3e6b4d..31a8535 100644 (file)
@@ -1053,15 +1053,15 @@ static int ssl3_get_key_exchange(SSL *s)
                                q+=i;
                                j+=i;
                                }
-                       i=RSA_public_decrypt((int)n,p,p,pkey->pkey.rsa,
-                               RSA_PKCS1_PADDING);
-                       if (i <= 0)
+                       i=RSA_verify(NID_md5_sha1, md_buf, j, p, n,
+                                                               pkey->pkey.rsa);
+                       if (i < 0)
                                {
                                al=SSL_AD_DECRYPT_ERROR;
                                SSLerr(SSL_F_SSL3_GET_KEY_EXCHANGE,SSL_R_BAD_RSA_DECRYPT);
                                goto f_err;
                                }
-                       if ((j != i) || (memcmp(p,md_buf,i) != 0))
+                       if (i == 0)
                                {
                                /* bad signature */
                                al=SSL_AD_DECRYPT_ERROR;
@@ -1481,11 +1481,9 @@ static int ssl3_send_client_verify(SSL *s)
                        {
                        s->method->ssl3_enc->cert_verify_mac(s,
                                &(s->s3->finish_dgst1),&(data[0]));
-                       i=RSA_private_encrypt(
-                               MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH,
-                               data,&(p[2]),pkey->pkey.rsa,
-                               RSA_PKCS1_PADDING);
-                       if (i <= 0)
+                       if (RSA_sign(NID_md5_sha1, data,
+                                        MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH,
+                                       &(p[2]), &i, pkey->pkey.rsa) <= 0 )
                                {
                                SSLerr(SSL_F_SSL3_SEND_CLIENT_VERIFY,ERR_R_RSA_LIB);
                                goto err;
index 0cefa09..d722ff3 100644 (file)
@@ -1026,9 +1026,8 @@ static int ssl3_send_server_key_exchange(SSL *s)
                                        q+=i;
                                        j+=i;
                                        }
-                               i=RSA_private_encrypt(j,md_buf,&(p[2]),
-                                       pkey->pkey.rsa,RSA_PKCS1_PADDING);
-                               if (i <= 0)
+                               if (RSA_sign(NID_md5_sha1, md_buf, j,
+                                       &(p[2]), &i, pkey->pkey.rsa) <= 0)
                                        {
                                        SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
                                        goto err;
@@ -1449,16 +1448,16 @@ static int ssl3_get_cert_verify(SSL *s)
 #ifndef NO_RSA 
        if (pkey->type == EVP_PKEY_RSA)
                {
-               i=RSA_public_decrypt(i,p,p,pkey->pkey.rsa,RSA_PKCS1_PADDING);
+               i=RSA_verify(NID_md5_sha1, s->s3->tmp.finish_md,
+                       MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH, p, i, 
+                                                       pkey->pkey.rsa);
                if (i < 0)
                        {
                        al=SSL_AD_DECRYPT_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_BAD_RSA_DECRYPT);
                        goto f_err;
                        }
-               if ((i != (MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH)) ||
-                       memcmp(&(s->s3->tmp.finish_md[0]),p,
-                               MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH))
+               if (i == 0)
                        {
                        al=SSL_AD_DECRYPT_ERROR;
                        SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_BAD_RSA_SIGNATURE);