Keep old method in case of an unsupported protocol
[openssl.git] / ssl / t1_enc.c
index c1518264c8c614eadcd937b3da731977b525afb3..4b9383adfaf0911b6dd7629d09c9f09ce5e73c99 100644 (file)
 
 #include <stdio.h>
 #include "ssl_locl.h"
+#ifndef OPENSSL_NO_COMP
 #include <openssl/comp.h>
+#endif
 #include <openssl/evp.h>
 #include <openssl/hmac.h>
 #include <openssl/md5.h>
+#ifdef KSSL_DEBUG
+#include <openssl/des.h>
+#endif
 
 static void tls1_P_hash(const EVP_MD *md, const unsigned char *sec,
                        int sec_len, unsigned char *seed, int seed_len,
                        unsigned char *out, int olen)
        {
-       int chunk,n;
+       int chunk;
        unsigned int j;
        HMAC_CTX ctx;
        HMAC_CTX ctx_tmp;
@@ -138,7 +143,6 @@ static void tls1_P_hash(const EVP_MD *md, const unsigned char *sec,
        HMAC_Update(&ctx,seed,seed_len);
        HMAC_Final(&ctx,A1,&A1_len);
 
-       n=0;
        for (;;)
                {
                HMAC_Init_ex(&ctx,NULL,0,NULL,NULL); /* re-init */
@@ -222,14 +226,14 @@ static void tls1_generate_key_block(SSL *s, unsigned char *km,
 int tls1_change_cipher_state(SSL *s, int which)
        {
        static const unsigned char empty[]="";
-       unsigned char *p,*key_block,*mac_secret;
+       unsigned char *p,*mac_secret;
        unsigned char *exp_label,buf[TLS_MD_MAX_CONST_SIZE+
                SSL3_RANDOM_SIZE*2];
        unsigned char tmp1[EVP_MAX_KEY_LENGTH];
        unsigned char tmp2[EVP_MAX_KEY_LENGTH];
        unsigned char iv1[EVP_MAX_IV_LENGTH*2];
        unsigned char iv2[EVP_MAX_IV_LENGTH*2];
-       unsigned char *ms,*key,*iv,*er1,*er2;
+       unsigned char *ms,*key,*iv;
        int client_write;
        EVP_CIPHER_CTX *dd;
        const EVP_CIPHER *c;
@@ -246,20 +250,21 @@ int tls1_change_cipher_state(SSL *s, int which)
 #ifndef OPENSSL_NO_COMP
        comp=s->s3->tmp.new_compression;
 #endif
-       key_block=s->s3->tmp.key_block;
 
 #ifdef KSSL_DEBUG
+       key_block=s->s3->tmp.key_block;
+
        printf("tls1_change_cipher_state(which= %d) w/\n", which);
        printf("\talg= %ld, comp= %p\n", s->s3->tmp.new_cipher->algorithms,
-                comp);
-       printf("\tevp_cipher == %p ==? &d_cbc_ede_cipher3\n", c);
+                (void *)comp);
+       printf("\tevp_cipher == %p ==? &d_cbc_ede_cipher3\n", (void *)c);
        printf("\tevp_cipher: nid, blksz= %d, %d, keylen=%d, ivlen=%d\n",
                 c->nid,c->block_size,c->key_len,c->iv_len);
        printf("\tkey_block: len= %d, data= ", s->s3->tmp.key_block_length);
        {
-        int i;
-        for (i=0; i<s->s3->tmp.key_block_length; i++)
-               printf("%02x", key_block[i]);  printf("\n");
+        int ki;
+        for (ki=0; ki<s->s3->tmp.key_block_length; ki++)
+               printf("%02x", s->s3->tmp.key_block[ki]);  printf("\n");
         }
 #endif /* KSSL_DEBUG */
 
@@ -343,8 +348,6 @@ int tls1_change_cipher_state(SSL *s, int which)
                       cl : SSL_C_EXPORT_KEYLENGTH(s->s3->tmp.new_cipher)) : cl;
        /* Was j=(exp)?5:EVP_CIPHER_key_length(c); */
        k=EVP_CIPHER_iv_length(c);
-       er1= &(s->s3->client_random[0]);
-       er2= &(s->s3->server_random[0]);
        if (    (which == SSL3_CHANGE_CIPHER_CLIENT_WRITE) ||
                (which == SSL3_CHANGE_CIPHER_SERVER_READ))
                {
@@ -415,11 +418,13 @@ printf("which = %04X\nmac key=",which);
        s->session->key_arg_length=0;
 #ifdef KSSL_DEBUG
        {
-        int i;
+        int ki;
        printf("EVP_CipherInit_ex(dd,c,key=,iv=,which)\n");
-       printf("\tkey= "); for (i=0; i<c->key_len; i++) printf("%02x", key[i]);
+       printf("\tkey= ");
+       for (ki=0; ki<c->key_len; ki++) printf("%02x", key[ki]);
        printf("\n");
-       printf("\t iv= "); for (i=0; i<c->iv_len; i++) printf("%02x", iv[i]);
+       printf("\t iv= ");
+       for (ki=0; ki<c->iv_len; ki++) printf("%02x", iv[ki]);
        printf("\n");
        }
 #endif /* KSSL_DEBUG */
@@ -523,18 +528,25 @@ err:
        return(0);
        }
 
+/* tls1_enc encrypts/decrypts the record in |s->wrec| / |s->rrec|, respectively.
+ *
+ * Returns:
+ *   0: (in non-constant time) if the record is publically invalid (i.e. too
+ *       short etc).
+ *   1: if the record's padding is valid / the encryption was successful.
+ *   -1: if the record's padding/AEAD-authenticator is invalid or, if sending,
+ *       an internal error occured.
+ */
 int tls1_enc(SSL *s, int send)
        {
        SSL3_RECORD *rec;
        EVP_CIPHER_CTX *ds;
        unsigned long l;
-       int bs,i,ii,j,k,n=0;
+       int bs,i,j,k,pad=0,ret,mac_size=0;
        const EVP_CIPHER *enc;
 
        if (send)
                {
-               if (s->write_hash != NULL)
-                       n=EVP_MD_size(s->write_hash);
                ds=s->enc_write_ctx;
                rec= &(s->s3->wrec);
                if (s->enc_write_ctx == NULL)
@@ -544,8 +556,6 @@ int tls1_enc(SSL *s, int send)
                }
        else
                {
-               if (s->read_hash != NULL)
-                       n=EVP_MD_size(s->read_hash);
                ds=s->enc_read_ctx;
                rec= &(s->s3->rrec);
                if (s->enc_read_ctx == NULL)
@@ -558,11 +568,11 @@ int tls1_enc(SSL *s, int send)
        printf("tls1_enc(%d)\n", send);
 #endif    /* KSSL_DEBUG */
 
-       if ((s->session == NULL) || (ds == NULL) ||
-               (enc == NULL))
+       if ((s->session == NULL) || (ds == NULL) || (enc == NULL))
                {
                memmove(rec->data,rec->input,rec->length);
                rec->input=rec->data;
+               ret = 1;
                }
        else
                {
@@ -590,13 +600,13 @@ int tls1_enc(SSL *s, int send)
 
 #ifdef KSSL_DEBUG
                {
-                unsigned long ui;
+               unsigned long ui;
                printf("EVP_Cipher(ds=%p,rec->data=%p,rec->input=%p,l=%ld) ==>\n",
-                        ds,rec->data,rec->input,l);
+                       ds,rec->data,rec->input,l);
                printf("\tEVP_CIPHER_CTX: %d buf_len, %d key_len [%d %d], %d iv_len\n",
-                        ds->buf_len, ds->cipher->key_len,
-                        DES_KEY_SZ, DES_SCHEDULE_SZ,
-                        ds->cipher->iv_len);
+                       ds->buf_len, ds->cipher->key_len,
+                       DES_KEY_SZ, DES_SCHEDULE_SZ,
+                       ds->cipher->iv_len);
                printf("\t\tIV: ");
                for (i=0; i<ds->cipher->iv_len; i++) printf("%02X", ds->iv[i]);
                printf("\n");
@@ -609,67 +619,29 @@ int tls1_enc(SSL *s, int send)
                if (!send)
                        {
                        if (l == 0 || l%bs != 0)
-                               {
-                               SSLerr(SSL_F_TLS1_ENC,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
-                               ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_DECRYPTION_FAILED);
                                return 0;
-                               }
                        }
                
                EVP_Cipher(ds,rec->data,rec->input,l);
 
 #ifdef KSSL_DEBUG
                {
-                unsigned long i;
+                unsigned long ki;
                 printf("\trec->data=");
-               for (i=0; i<l; i++)
-                        printf(" %02x", rec->data[i]);  printf("\n");
+               for (ki=0; ki<l; i++)
+                        printf(" %02x", rec->data[ki]);  printf("\n");
                 }
 #endif /* KSSL_DEBUG */
 
+               ret = 1;
+               if (s->read_hash != NULL)
+                       mac_size = EVP_MD_size(s->read_hash);
                if ((bs != 1) && !send)
-                       {
-                       ii=i=rec->data[l-1]; /* padding_length */
-                       i++;
-                       /* NB: if compression is in operation the first packet
-                        * may not be of even length so the padding bug check
-                        * cannot be performed. This bug workaround has been
-                        * around since SSLeay so hopefully it is either fixed
-                        * now or no buggy implementation supports compression 
-                        * [steve]
-                        */
-                       if ( (s->options&SSL_OP_TLS_BLOCK_PADDING_BUG)
-                               && !s->expand)
-                               {
-                               /* First packet is even in size, so check */
-                               if ((memcmp(s->s3->read_sequence,
-                                       "\0\0\0\0\0\0\0\0",8) == 0) && !(ii & 1))
-                                       s->s3->flags|=TLS1_FLAGS_TLS_PADDING_BUG;
-                               if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
-                                       i--;
-                               }
-                       /* TLS 1.0 does not bound the number of padding bytes by the block size.
-                        * All of them must have value 'padding_length'. */
-                       if (i > (int)rec->length)
-                               {
-                               /* Incorrect padding. SSLerr() and ssl3_alert are done
-                                * by caller: we don't want to reveal whether this is
-                                * a decryption error or a MAC verification failure
-                                * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
-                               return -1;
-                               }
-                       for (j=(int)(l-i); j<(int)l; j++)
-                               {
-                               if (rec->data[j] != ii)
-                                       {
-                                       /* Incorrect padding */
-                                       return -1;
-                                       }
-                               }
-                       rec->length-=i;
-                       }
+                       ret = tls1_cbc_remove_padding(s, rec, bs, mac_size);
+               if (pad && !send)
+                       rec->length -= pad;
                }
-       return(1);
+       return ret;
        }
 
 int tls1_cert_verify_mac(SSL *s, EVP_MD_CTX *in_ctx, unsigned char *out)
@@ -717,10 +689,10 @@ int tls1_mac(SSL *ssl, unsigned char *md, int send)
        SSL3_RECORD *rec;
        unsigned char *mac_sec,*seq;
        const EVP_MD *hash;
-       unsigned int md_size;
+       size_t md_size, orig_len;
        int i;
        HMAC_CTX hmac;
-       unsigned char buf[5]; 
+       unsigned char header[13];
 
        if (send)
                {
@@ -739,53 +711,76 @@ int tls1_mac(SSL *ssl, unsigned char *md, int send)
 
        md_size=EVP_MD_size(hash);
 
-       buf[0]=rec->type;
-       if (ssl->version == DTLS1_VERSION && ssl->client_version == DTLS1_BAD_VER)
-               {
-               buf[1]=TLS1_VERSION_MAJOR;
-               buf[2]=TLS1_VERSION_MINOR;
-               }
-       else    {
-               buf[1]=(unsigned char)(ssl->version>>8);
-               buf[2]=(unsigned char)(ssl->version);
-               }
-
-       buf[3]=rec->length>>8;
-       buf[4]=rec->length&0xff;
-
        /* I should fix this up TLS TLS TLS TLS TLS XXXXXXXX */
        HMAC_CTX_init(&hmac);
        HMAC_Init_ex(&hmac,mac_sec,EVP_MD_size(hash),hash,NULL);
 
-       if (ssl->version == DTLS1_VERSION && ssl->client_version != DTLS1_BAD_VER)
+       if (ssl->version == DTLS1_BAD_VER ||
+           (ssl->version == DTLS1_VERSION && ssl->client_version != DTLS1_BAD_VER))
                {
                unsigned char dtlsseq[8],*p=dtlsseq;
-
                s2n(send?ssl->d1->w_epoch:ssl->d1->r_epoch, p);
                memcpy (p,&seq[2],6);
 
-               HMAC_Update(&hmac,dtlsseq,8);
+               memcpy(header, dtlsseq, 8);
                }
        else
-               HMAC_Update(&hmac,seq,8);
+               memcpy(header, seq, 8);
 
-       HMAC_Update(&hmac,buf,5);
-       HMAC_Update(&hmac,rec->input,rec->length);
-       HMAC_Final(&hmac,md,&md_size);
-       HMAC_CTX_cleanup(&hmac);
+       /* kludge: tls1_cbc_remove_padding passes padding length in rec->type */
+       orig_len = rec->length+md_size+((unsigned int)rec->type>>8);
+       rec->type &= 0xff;
+
+       header[8]=rec->type;
+       header[9]=(unsigned char)(ssl->version>>8);
+       header[10]=(unsigned char)(ssl->version);
+       header[11]=(rec->length)>>8;
+       header[12]=(rec->length)&0xff;
 
+       if (!send &&
+           EVP_CIPHER_CTX_mode(ssl->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
+           ssl3_cbc_record_digest_supported(hash))
+               {
+               /* This is a CBC-encrypted record. We must avoid leaking any
+                * timing-side channel information about how many blocks of
+                * data we are hashing because that gives an attacker a
+                * timing-oracle. */
+               ssl3_cbc_digest_record(
+                       hash,
+                       md, &md_size,
+                       header, rec->input,
+                       rec->length + md_size, orig_len,
+                       ssl->s3->read_mac_secret,
+                       EVP_MD_size(ssl->read_hash),
+                       0 /* not SSLv3 */);
+               }
+       else
+               {
+               unsigned mds;
+
+               HMAC_Update(&hmac,header,sizeof(header));
+               HMAC_Update(&hmac,rec->input,rec->length);
+               HMAC_Final(&hmac,md,&mds);
+               md_size = mds;
+#ifdef OPENSSL_FIPS
+               if (!send && FIPS_mode())
+                       tls_fips_digest_extra(
+                                       ssl->enc_read_ctx,
+                                       hash,
+                                       &hmac, rec->input,
+                                       rec->length, orig_len);
+#endif
+               }
+               
+       HMAC_CTX_cleanup(&hmac);
 #ifdef TLS_DEBUG
-printf("sec=");
-{unsigned int z; for (z=0; z<md_size; z++) printf("%02X ",mac_sec[z]); printf("\n"); }
 printf("seq=");
 {int z; for (z=0; z<8; z++) printf("%02X ",seq[z]); printf("\n"); }
-printf("buf=");
-{int z; for (z=0; z<5; z++) printf("%02X ",buf[z]); printf("\n"); }
 printf("rec=");
-{unsigned int z; for (z=0; z<rec->length; z++) printf("%02X ",buf[z]); printf("\n"); }
+{unsigned int z; for (z=0; z<rec->length; z++) printf("%02X ",rec->data[z]); printf("\n"); }
 #endif
 
-       if ( SSL_version(ssl) != DTLS1_VERSION)
+       if ( SSL_version(ssl) != DTLS1_VERSION && SSL_version(ssl) != DTLS1_BAD_VER)
                {
                for (i=7; i>=0; i--)
                        {
@@ -807,7 +802,7 @@ int tls1_generate_master_secret(SSL *s, unsigned char *out, unsigned char *p,
        unsigned char buff[SSL_MAX_MASTER_KEY_LENGTH];
 
 #ifdef KSSL_DEBUG
-       printf ("tls1_generate_master_secret(%p,%p, %p, %d)\n", s,out, p,len);
+       printf ("tls1_generate_master_secret(%p,%p, %p, %d)\n", (void *)s,out, p,len);
 #endif /* KSSL_DEBUG */
 
        /* Setup the stuff to munge */
@@ -854,9 +849,17 @@ int tls1_alert_code(int code)
        case SSL_AD_INTERNAL_ERROR:     return(TLS1_AD_INTERNAL_ERROR);
        case SSL_AD_USER_CANCELLED:     return(TLS1_AD_USER_CANCELLED);
        case SSL_AD_NO_RENEGOTIATION:   return(TLS1_AD_NO_RENEGOTIATION);
+       case SSL_AD_UNSUPPORTED_EXTENSION: return(TLS1_AD_UNSUPPORTED_EXTENSION);
+       case SSL_AD_CERTIFICATE_UNOBTAINABLE: return(TLS1_AD_CERTIFICATE_UNOBTAINABLE);
+       case SSL_AD_UNRECOGNIZED_NAME:  return(TLS1_AD_UNRECOGNIZED_NAME);
+       case SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE: return(TLS1_AD_BAD_CERTIFICATE_STATUS_RESPONSE);
+       case SSL_AD_BAD_CERTIFICATE_HASH_VALUE: return(TLS1_AD_BAD_CERTIFICATE_HASH_VALUE);
+       case SSL_AD_UNKNOWN_PSK_IDENTITY:return(TLS1_AD_UNKNOWN_PSK_IDENTITY);
+       case SSL_AD_INAPPROPRIATE_FALLBACK:return(TLS1_AD_INAPPROPRIATE_FALLBACK);
+#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
        case DTLS1_AD_MISSING_HANDSHAKE_MESSAGE: return 
                                          (DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
+#endif
        default:                        return(-1);
                }
        }
-