Abort handshake if signature algorithm used not supported by peer.
[openssl.git] / ssl / t1_lib.c
index 48b2c42e4a11752d7f050af1d27670c39005b0d2..05df5fe491cccd0eb93b785f6d4d5ced13b32cbf 100644 (file)
@@ -123,7 +123,7 @@ const char tls1_version_str[]="TLSv1" OPENSSL_VERSION_PTEXT;
 static int tls_decrypt_ticket(SSL *s, const unsigned char *tick, int ticklen,
                                const unsigned char *sess_id, int sesslen,
                                SSL_SESSION **psess);
-static int ssl_check_clienthello_tlsext(SSL *s);
+static int ssl_check_clienthello_tlsext_early(SSL *s);
 int ssl_check_serverhello_tlsext(SSL *s);
 #endif
 
@@ -333,6 +333,21 @@ static void tls1_get_curvelist(SSL *s, int sess,
                *pcurveslen = sizeof(eccurves_default);
                }
        }
+/* Check a curve is one of our preferences */
+int tls1_check_curve(SSL *s, const unsigned char *p, size_t len)
+       {
+       const unsigned char *curves;
+       size_t curveslen, i;
+       if (len != 3 || p[0] != NAMED_CURVE_TYPE)
+               return 0;
+       tls1_get_curvelist(s, 0, &curves, &curveslen);
+       for (i = 0; i < curveslen; i += 2, curves += 2)
+               {
+               if (p[1] == curves[0] && p[2] == curves[1])
+                       return 1;
+               }
+       return 0;
+       }
 
 /* Return nth shared curve. If nmatch == -1 return number of
  * matches.
@@ -539,18 +554,24 @@ static int tls1_check_ec_key(SSL *s,
                }
        return 1;
        }
-/* Check EC server key is compatible with client extensions */
-int tls1_check_ec_server_key(SSL *s)
+
+/* Check cert parameters compatible with extensions: currently just checks
+ * EC certificates have compatible curves and compression.
+ */
+static int tls1_check_cert_param(SSL *s, X509 *x)
        {
-       int rv;
-       CERT_PKEY *cpk = s->cert->pkeys + SSL_PKEY_ECC;
-       EVP_PKEY *pkey;
        unsigned char comp_id, curve_id[2];
-       if (!cpk->x509 || !cpk->privatekey)
-               return 0;
-       pkey = X509_get_pubkey(cpk->x509);
+       EVP_PKEY *pkey;
+       int rv;
+       pkey = X509_get_pubkey(x);
        if (!pkey)
                return 0;
+       /* If not EC nothing to do */
+       if (pkey->type != EVP_PKEY_EC)
+               {
+               EVP_PKEY_free(pkey);
+               return 1;
+               }
        rv = tls1_set_ec_id(curve_id, &comp_id, pkey->pkey.ec);
        EVP_PKEY_free(pkey);
        if (!rv)
@@ -577,8 +598,13 @@ int tls1_check_ec_tmp_key(SSL *s)
                        return 0;
                }
        if (!tls1_set_ec_id(curve_id, NULL, ec))
-               return 1;
+               return 0;
+/* Set this to allow use of invalid curves for testing */
+#if 0
+       return 1;
+#else
        return tls1_check_ec_key(s, curve_id, NULL);
+#endif
        }
 
 #endif /* OPENSSL_NO_EC */
@@ -629,17 +655,149 @@ static unsigned char tls12_sigalgs[] = {
 #endif
 };
 
-int tls12_get_req_sig_algs(SSL *s, unsigned char *p)
+size_t tls12_get_psigalgs(SSL *s, const unsigned char **psigs)
        {
-       size_t slen = sizeof(tls12_sigalgs);
+       /* If server use client authentication sigalgs if not NULL */
+       if (s->server && s->cert->client_sigalgs)
+               {
+               *psigs = s->cert->client_sigalgs;
+               return s->cert->client_sigalgslen;
+               }
+       else if (s->cert->conf_sigalgs)
+               {
+               *psigs = s->cert->conf_sigalgs;
+               return s->cert->conf_sigalgslen;
+               }
+       else
+               {
+               *psigs = tls12_sigalgs;
 #ifdef OPENSSL_FIPS
-       /* If FIPS mode don't include MD5 which is last */
-       if (FIPS_mode())
-               slen -= 2;
+               /* If FIPS mode don't include MD5 which is last */
+               if (FIPS_mode())
+                       return sizeof(tls12_sigalgs) - 2;
+               else
 #endif
-       if (p)
-               memcpy(p, tls12_sigalgs, slen);
-       return (int)slen;
+                       return sizeof(tls12_sigalgs);
+               }
+       }
+/* Check signature algorithm is consistent with sent supported signature
+ * algorithms and if so return relevant digest.
+ */
+int tls12_check_peer_sigalg(const EVP_MD **pmd, SSL *s,
+                               const unsigned char *sig, EVP_PKEY *pkey)
+       {
+       const unsigned char *sent_sigs;
+       size_t sent_sigslen, i;
+       int sigalg = tls12_get_sigid(pkey);
+       /* Should never happen */
+       if (sigalg == -1)
+               return -1;
+       /* Check key type is consistent with signature */
+       if (sigalg != (int)sig[1])
+               {
+               SSLerr(SSL_F_TLS12_CHECK_PEER_SIGALG,SSL_R_WRONG_SIGNATURE_TYPE);
+               return 0;
+               }
+       /* Check signature matches a type we sent */
+       sent_sigslen = tls12_get_psigalgs(s, &sent_sigs);
+       for (i = 0; i < sent_sigslen; i+=2, sent_sigs+=2)
+               {
+               if (sig[0] == sent_sigs[0] && sig[1] == sent_sigs[1])
+                       break;
+               }
+       /* Allow fallback to SHA1 if not strict mode */
+       if (i == sent_sigslen && (sig[0] != TLSEXT_hash_sha1 || s->cert->cert_flags & SSL_CERT_FLAG_TLS_STRICT))
+               {
+               SSLerr(SSL_F_TLS12_CHECK_PEER_SIGALG,SSL_R_WRONG_SIGNATURE_TYPE);
+               return 0;
+               }
+       *pmd = tls12_get_hash(sig[0]);
+       if (*pmd == NULL)
+               {
+               SSLerr(SSL_F_TLS12_CHECK_PEER_SIGALG,SSL_R_UNKNOWN_DIGEST);
+               return 0;
+               }
+       return 1;
+       }
+/* Get a mask of disabled algorithms: an algorithm is disabled
+ * if it isn't supported or doesn't appear in supported signature
+ * algorithms. Unlike ssl_cipher_get_disabled this applies to a specific
+ * session and not global settings.
+ * 
+ */
+void ssl_set_client_disabled(SSL *s)
+       {
+       CERT *c = s->cert;
+       const unsigned char *sigalgs;
+       size_t i, sigalgslen;
+       int have_rsa = 0, have_dsa = 0, have_ecdsa = 0;
+       c->mask_a = 0;
+       c->mask_k = 0;
+       /* If less than TLS 1.2 don't allow TLS 1.2 only ciphers */
+       if (TLS1_get_version(s) < TLS1_2_VERSION)
+               c->mask_ssl = SSL_TLSV1_2;
+       else
+               c->mask_ssl = 0;
+       /* Now go through all signature algorithms seeing if we support
+        * any for RSA, DSA, ECDSA. Do this for all versions not just
+        * TLS 1.2.
+        */
+       sigalgslen = tls12_get_psigalgs(s, &sigalgs);
+       for (i = 0; i < sigalgslen; i += 2, sigalgs += 2)
+               {
+               switch(sigalgs[1])
+                       {
+#ifndef OPENSSL_NO_RSA
+               case TLSEXT_signature_rsa:
+                       have_rsa = 1;
+                       break;
+#endif
+#ifndef OPENSSL_NO_DSA
+               case TLSEXT_signature_dsa:
+                       have_dsa = 1;
+                       break;
+#endif
+#ifndef OPENSSL_NO_ECDSA
+               case TLSEXT_signature_ecdsa:
+                       have_ecdsa = 1;
+                       break;
+#endif
+                       }
+               }
+       /* Disable auth and static DH if we don't include any appropriate
+        * signature algorithms.
+        */
+       if (!have_rsa)
+               {
+               c->mask_a |= SSL_aRSA;
+               c->mask_k |= SSL_kDHr|SSL_kECDHr;
+               }
+       if (!have_dsa)
+               {
+               c->mask_a |= SSL_aDSS;
+               c->mask_k |= SSL_kDHd;
+               }
+       if (!have_ecdsa)
+               {
+               c->mask_a |= SSL_aECDSA;
+               c->mask_k |= SSL_kECDHe;
+               }
+#ifndef OPENSSL_NO_KRB5
+       if (!kssl_tgt_is_available(s->kssl_ctx))
+               {
+               c->mask_a |= SSL_aKRB5;
+               c->mask_k |= SSL_kKRB5;
+               }
+#endif
+#ifndef OPENSSL_NO_PSK
+       /* with PSK there must be client callback set */
+       if (!s->psk_client_callback)
+               {
+               c->mask_a |= SSL_aPSK;
+               c->mask_k |= SSL_kPSK;
+               }
+#endif /* OPENSSL_NO_PSK */
+       c->valid = 1;
        }
 
 /* byte_compare is a compare function for qsort(3) that compares bytes. */
@@ -872,15 +1030,18 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned cha
                }
                skip_ext:
 
-       if (TLS1_get_client_version(s) >= TLS1_2_VERSION && 0)
+       if (TLS1_get_client_version(s) >= TLS1_2_VERSION)
                {
-               if ((size_t)(limit - ret) < sizeof(tls12_sigalgs) + 6)
+               size_t salglen;
+               const unsigned char *salg;
+               salglen = tls12_get_psigalgs(s, &salg);
+               if ((size_t)(limit - ret) < salglen + 6)
                        return NULL; 
                s2n(TLSEXT_TYPE_signature_algorithms,ret);
-               s2n(sizeof(tls12_sigalgs) + 2, ret);
-               s2n(sizeof(tls12_sigalgs), ret);
-               memcpy(ret, tls12_sigalgs, sizeof(tls12_sigalgs));
-               ret += sizeof(tls12_sigalgs);
+               s2n(salglen + 2, ret);
+               s2n(salglen, ret);
+               memcpy(ret, salg, salglen);
+               ret += salglen;
                }
 
 #ifdef TLSEXT_TYPE_opaque_prf_input
@@ -1290,7 +1451,6 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
        unsigned short len;
        unsigned char *data = *p;
        int renegotiate_seen = 0;
-       int sigalg_seen = 0;
 
        s->servername_done = 0;
        s->tlsext_status_type = -1;
@@ -1302,6 +1462,18 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
        s->tlsext_heartbeat &= ~(SSL_TLSEXT_HB_ENABLED |
                               SSL_TLSEXT_HB_DONT_SEND_REQUESTS);
 #endif
+       /* Clear any signature algorithms extension received */
+       if (s->cert->peer_sigalgs)
+               {
+               OPENSSL_free(s->cert->peer_sigalgs);
+               s->cert->peer_sigalgs = NULL;
+               }
+       /* Clear any shared sigtnature algorithms */
+       if (s->cert->shared_sigalgs)
+               {
+               OPENSSL_free(s->cert->shared_sigalgs);
+               s->cert->shared_sigalgs = NULL;
+               }
 
        if (data >= (d+n-2))
                goto ri_check;
@@ -1498,7 +1670,8 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
                        int ellipticcurvelist_length = (*(sdata++) << 8);
                        ellipticcurvelist_length += (*(sdata++));
 
-                       if (ellipticcurvelist_length != size - 2)
+                       if (ellipticcurvelist_length != size - 2 ||
+                               ellipticcurvelist_length < 1)
                                {
                                *al = TLS1_AD_DECODE_ERROR;
                                return 0;
@@ -1577,15 +1750,14 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
                else if (type == TLSEXT_TYPE_signature_algorithms)
                        {
                        int dsize;
-                       if (sigalg_seen || size < 2) 
+                       if (s->cert->peer_sigalgs || size < 2) 
                                {
                                *al = SSL_AD_DECODE_ERROR;
                                return 0;
                                }
-                       sigalg_seen = 1;
                        n2s(data,dsize);
                        size -= 2;
-                       if (dsize != size || dsize & 1) 
+                       if (dsize != size || dsize & 1 || !dsize
                                {
                                *al = SSL_AD_DECODE_ERROR;
                                return 0;
@@ -1595,6 +1767,16 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
                                *al = SSL_AD_DECODE_ERROR;
                                return 0;
                                }
+                       /* If sigalgs received and no shared algorithms fatal
+                        * error.
+                        */
+                       if (s->cert->peer_sigalgs && !s->cert->shared_sigalgs)
+                               {
+                               SSLerr(SSL_F_SSL_SCAN_CLIENTHELLO_TLSEXT,
+                                       SSL_R_NO_SHARED_SIGATURE_ALGORITHMS);
+                               *al = SSL_AD_ILLEGAL_PARAMETER;
+                               return 0;
+                               }
                        }
                else if (type == TLSEXT_TYPE_status_request &&
                         s->version != DTLS1_VERSION && s->ctx->tlsext_status_cb)
@@ -1833,6 +2015,9 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
                                SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
                return 0;
                }
+       /* If no signature algorithms extension set default values */
+       if (!s->cert->peer_sigalgs)
+               ssl_cert_set_default_md(s->cert);
 
        return 1;
        }
@@ -1846,7 +2031,7 @@ int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char *d, in
                return 0;
                }
 
-       if (ssl_check_clienthello_tlsext(s) <= 0) 
+       if (ssl_check_clienthello_tlsext_early(s) <= 0) 
                {
                SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_TLSEXT,SSL_R_CLIENTHELLO_TLSEXT);
                return 0;
@@ -1931,7 +2116,8 @@ static int ssl_scan_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char
                        unsigned char *sdata = data;
                        int ecpointformatlist_length = *(sdata++);
 
-                       if (ecpointformatlist_length != size - 1)
+                       if (ecpointformatlist_length != size - 1 || 
+                               ecpointformatlist_length < 1)
                                {
                                *al = TLS1_AD_DECODE_ERROR;
                                return 0;
@@ -2247,7 +2433,7 @@ int ssl_prepare_serverhello_tlsext(SSL *s)
        return 1;
        }
 
-static int ssl_check_clienthello_tlsext(SSL *s)
+static int ssl_check_clienthello_tlsext_early(SSL *s)
        {
        int ret=SSL_TLSEXT_ERR_NOACK;
        int al = SSL_AD_UNRECOGNIZED_NAME;
@@ -2266,42 +2452,12 @@ static int ssl_check_clienthello_tlsext(SSL *s)
        else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)             
                ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
 
-       /* If status request then ask callback what to do.
-        * Note: this must be called after servername callbacks in case 
-        * the certificate has changed.
-        */
-       if ((s->tlsext_status_type != -1) && s->ctx && s->ctx->tlsext_status_cb)
-               {
-               int r;
-               r = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg);
-               switch (r)
-                       {
-                       /* We don't want to send a status request response */
-                       case SSL_TLSEXT_ERR_NOACK:
-                               s->tlsext_status_expected = 0;
-                               break;
-                       /* status request response should be sent */
-                       case SSL_TLSEXT_ERR_OK:
-                               if (s->tlsext_ocsp_resp)
-                                       s->tlsext_status_expected = 1;
-                               else
-                                       s->tlsext_status_expected = 0;
-                               break;
-                       /* something bad happened */
-                       case SSL_TLSEXT_ERR_ALERT_FATAL:
-                               ret = SSL_TLSEXT_ERR_ALERT_FATAL;
-                               al = SSL_AD_INTERNAL_ERROR;
-                               goto err;
-                       }
-               }
-       else
-               s->tlsext_status_expected = 0;
-
 #ifdef TLSEXT_TYPE_opaque_prf_input
        {
                /* This sort of belongs into ssl_prepare_serverhello_tlsext(),
                 * but we might be sending an alert in response to the client hello,
-                * so this has to happen here in ssl_check_clienthello_tlsext(). */
+                * so this has to happen here in
+                * ssl_check_clienthello_tlsext_early(). */
 
                int r = 1;
        
@@ -2353,8 +2509,8 @@ static int ssl_check_clienthello_tlsext(SSL *s)
                        }
        }
 
-#endif
  err:
+#endif
        switch (ret)
                {
                case SSL_TLSEXT_ERR_ALERT_FATAL:
@@ -2372,6 +2528,71 @@ static int ssl_check_clienthello_tlsext(SSL *s)
                }
        }
 
+int ssl_check_clienthello_tlsext_late(SSL *s)
+       {
+       int ret = SSL_TLSEXT_ERR_OK;
+       int al;
+
+       /* If status request then ask callback what to do.
+        * Note: this must be called after servername callbacks in case
+        * the certificate has changed, and must be called after the cipher
+        * has been chosen because this may influence which certificate is sent
+        */
+       if ((s->tlsext_status_type != -1) && s->ctx && s->ctx->tlsext_status_cb)
+               {
+               int r;
+               CERT_PKEY *certpkey;
+               certpkey = ssl_get_server_send_pkey(s);
+               /* If no certificate can't return certificate status */
+               if (certpkey == NULL)
+                       {
+                       s->tlsext_status_expected = 0;
+                       return 1;
+                       }
+               /* Set current certificate to one we will use so
+                * SSL_get_certificate et al can pick it up.
+                */
+               s->cert->key = certpkey;
+               r = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg);
+               switch (r)
+                       {
+                       /* We don't want to send a status request response */
+                       case SSL_TLSEXT_ERR_NOACK:
+                               s->tlsext_status_expected = 0;
+                               break;
+                       /* status request response should be sent */
+                       case SSL_TLSEXT_ERR_OK:
+                               if (s->tlsext_ocsp_resp)
+                                       s->tlsext_status_expected = 1;
+                               else
+                                       s->tlsext_status_expected = 0;
+                               break;
+                       /* something bad happened */
+                       case SSL_TLSEXT_ERR_ALERT_FATAL:
+                               ret = SSL_TLSEXT_ERR_ALERT_FATAL;
+                               al = SSL_AD_INTERNAL_ERROR;
+                               goto err;
+                       }
+               }
+       else
+               s->tlsext_status_expected = 0;
+
+ err:
+       switch (ret)
+               {
+               case SSL_TLSEXT_ERR_ALERT_FATAL:
+                       ssl3_send_alert(s, SSL3_AL_FATAL,al);
+                       return -1;
+
+               case SSL_TLSEXT_ERR_ALERT_WARNING:
+                       ssl3_send_alert(s, SSL3_AL_WARNING,al);
+                       return 1; 
+
+               default:
+                       return 1;
+               }
+       }
+
 int ssl_check_serverhello_tlsext(SSL *s)
        {
        int ret=SSL_TLSEXT_ERR_NOACK;
@@ -2839,11 +3060,153 @@ const EVP_MD *tls12_get_hash(unsigned char hash_alg)
                }
        }
 
+static int tls12_get_pkey_idx(unsigned char sig_alg)
+       {
+       switch(sig_alg)
+               {
+#ifndef OPENSSL_NO_RSA
+       case TLSEXT_signature_rsa:
+               return SSL_PKEY_RSA_SIGN;
+#endif
+#ifndef OPENSSL_NO_DSA
+       case TLSEXT_signature_dsa:
+               return SSL_PKEY_DSA_SIGN;
+#endif
+#ifndef OPENSSL_NO_ECDSA
+       case TLSEXT_signature_ecdsa:
+               return SSL_PKEY_ECC;
+#endif
+               }
+       return -1;
+       }
+
+/* Convert TLS 1.2 signature algorithm extension values into NIDs */
+static void tls1_lookup_sigalg(int *phash_nid, int *psign_nid,
+                       int *psignhash_nid, const unsigned char *data)
+       {
+       int sign_nid = 0, hash_nid = 0;
+       if (!phash_nid && !psign_nid && !psignhash_nid)
+               return;
+       if (phash_nid || psignhash_nid)
+               {
+               hash_nid = tls12_find_nid(data[0], tls12_md,
+                                       sizeof(tls12_md)/sizeof(tls12_lookup));
+               if (phash_nid)
+                       *phash_nid = hash_nid;
+               }
+       if (psign_nid || psignhash_nid)
+               {
+               sign_nid = tls12_find_nid(data[1], tls12_sig,
+                                       sizeof(tls12_sig)/sizeof(tls12_lookup));
+               if (psign_nid)
+                       *psign_nid = sign_nid;
+               }
+       if (psignhash_nid)
+               {
+               if (sign_nid && hash_nid)
+                       OBJ_find_sigid_by_algs(psignhash_nid,
+                                                       hash_nid, sign_nid);
+               else
+                       *psignhash_nid = NID_undef;
+               }
+       }
+/* Given preference and allowed sigalgs set shared sigalgs */
+static int tls12_do_shared_sigalgs(TLS_SIGALGS *shsig,
+                               const unsigned char *pref, size_t preflen,
+                               const unsigned char *allow, size_t allowlen)
+       {
+       const unsigned char *ptmp, *atmp;
+       size_t i, j, nmatch = 0;
+       for (i = 0, ptmp = pref; i < preflen; i+=2, ptmp+=2)
+               {
+               /* Skip disabled hashes or signature algorithms */
+               if (tls12_get_hash(ptmp[0]) == NULL)
+                       continue;
+               if (tls12_get_pkey_idx(ptmp[1]) == -1)
+                       continue;
+               for (j = 0, atmp = allow; j < allowlen; j+=2, atmp+=2)
+                       {
+                       if (ptmp[0] == atmp[0] && ptmp[1] == atmp[1])
+                               {
+                               nmatch++;
+                               if (shsig)
+                                       {
+                                       shsig->rhash = ptmp[0];
+                                       shsig->rsign = ptmp[1];
+                                       tls1_lookup_sigalg(&shsig->hash_nid,
+                                               &shsig->sign_nid,
+                                               &shsig->signandhash_nid,
+                                               ptmp);
+                                       shsig++;
+                                       }
+                               break;
+                               }
+                       }
+               }
+       return nmatch;
+       }
+
+/* Set shared signature algorithms for SSL structures */
+static int tls1_set_shared_sigalgs(SSL *s)
+       {
+       const unsigned char *pref, *allow, *conf;
+       size_t preflen, allowlen, conflen;
+       size_t nmatch;
+       TLS_SIGALGS *salgs = NULL;
+       CERT *c = s->cert;
+       /* If client use client signature algorithms if not NULL */
+       if (!s->server && c->client_sigalgs)
+               {
+               conf = c->client_sigalgs;
+               conflen = c->client_sigalgslen;
+               }
+       else if (c->conf_sigalgs)
+               {
+               conf = c->conf_sigalgs;
+               conflen = c->conf_sigalgslen;
+               }
+       else
+               {
+               conf = tls12_sigalgs;
+               conflen = sizeof(tls12_sigalgs);
+#ifdef OPENSSL_FIPS
+               if (FIPS_mode())
+                       conflen -= 2;
+#endif
+               }
+       if(s->options & SSL_OP_CIPHER_SERVER_PREFERENCE)
+               {
+               pref = conf;
+               preflen = conflen;
+               allow = c->peer_sigalgs;
+               allowlen = c->peer_sigalgslen;
+               }
+       else
+               {
+               allow = conf;
+               allowlen = conflen;
+               pref = c->peer_sigalgs;
+               preflen = c->peer_sigalgslen;
+               }
+       nmatch = tls12_do_shared_sigalgs(NULL, pref, preflen, allow, allowlen);
+       if (!nmatch)
+               return 1;
+       salgs = OPENSSL_malloc(nmatch * sizeof(TLS_SIGALGS));
+       if (!salgs)
+               return 0;
+       nmatch = tls12_do_shared_sigalgs(salgs, pref, preflen, allow, allowlen);
+       c->shared_sigalgs = salgs;
+       c->shared_sigalgslen = nmatch;
+       return 1;
+       }
+               
+
 /* Set preferred digest for each key type */
 
 int tls1_process_sigalgs(SSL *s, const unsigned char *data, int dsize)
        {
-       int i, idx;
+       int idx;
+       size_t i;
        const EVP_MD *md;
        CERT *c = s->cert;
        TLS_SIGALGS *sigptr;
@@ -2859,107 +3222,96 @@ int tls1_process_sigalgs(SSL *s, const unsigned char *data, int dsize)
        c->pkeys[SSL_PKEY_RSA_ENC].digest = NULL;
        c->pkeys[SSL_PKEY_ECC].digest = NULL;
 
-       if (c->sigalgs)
-               OPENSSL_free(c->sigalgs);
-       c->sigalgs = OPENSSL_malloc((dsize/2) * sizeof(TLS_SIGALGS));
-       if (!c->sigalgs)
+       c->peer_sigalgs = OPENSSL_malloc(dsize);
+       if (!c->peer_sigalgs)
                return 0;
-       c->sigalgslen = dsize/2;
+       c->peer_sigalgslen = dsize;
+       memcpy(c->peer_sigalgs, data, dsize);
 
-       for (i = 0, sigptr = c->sigalgs; i < dsize; i += 2, sigptr++)
-               {
-               sigptr->rhash = data[i];
-               sigptr->rsign = data[i + 1];
-               sigptr->hash_nid = tls12_find_nid(sigptr->rhash, tls12_md,
-                                       sizeof(tls12_md)/sizeof(tls12_lookup));
-               sigptr->sign_nid = tls12_find_nid(sigptr->rsign, tls12_sig,
-                                       sizeof(tls12_sig)/sizeof(tls12_lookup));
-               if (!OBJ_find_sigid_by_algs(&sigptr->signandhash_nid,
-                                               sigptr->hash_nid,
-                                               sigptr->sign_nid))
-                       sigptr->signandhash_nid = NID_undef;
-               switch(sigptr->rsign)
-                       {
-#ifndef OPENSSL_NO_RSA
-                       case TLSEXT_signature_rsa:
-                       idx = SSL_PKEY_RSA_SIGN;
-                       break;
-#endif
-#ifndef OPENSSL_NO_DSA
-                       case TLSEXT_signature_dsa:
-                       idx = SSL_PKEY_DSA_SIGN;
-                       break;
-#endif
-#ifndef OPENSSL_NO_ECDSA
-                       case TLSEXT_signature_ecdsa:
-                       idx = SSL_PKEY_ECC;
-                       break;
-#endif
-                       default:
-                       continue;
-                       }
+       tls1_set_shared_sigalgs(s);
 
-               if (c->pkeys[idx].digest == NULL)
+       for (i = 0, sigptr = c->shared_sigalgs;
+                       i < c->shared_sigalgslen; i++, sigptr++)
+               {
+               idx = tls12_get_pkey_idx(sigptr->rsign);
+               if (idx > 0 && c->pkeys[idx].digest == NULL)
                        {
                        md = tls12_get_hash(sigptr->rhash);
-                       if (md)
-                               {
-                               c->pkeys[idx].digest = md;
-                               if (idx == SSL_PKEY_RSA_SIGN)
-                                       c->pkeys[SSL_PKEY_RSA_ENC].digest = md;
-                               }
+                       c->pkeys[idx].digest = md;
+                       if (idx == SSL_PKEY_RSA_SIGN)
+                               c->pkeys[SSL_PKEY_RSA_ENC].digest = md;
                        }
 
                }
-
-
-       /* Set any remaining keys to default values. NOTE: if alg is not
-        * supported it stays as NULL.
+       /* In strict mode leave unset digests as NULL to indicate we can't
+        * use the certificate for signing.
         */
+       if (!(s->cert->cert_flags & SSL_CERT_FLAG_TLS_STRICT))
+               {
+               /* Set any remaining keys to default values. NOTE: if alg is
+                * not supported it stays as NULL.
+                */
 #ifndef OPENSSL_NO_DSA
-       if (!c->pkeys[SSL_PKEY_DSA_SIGN].digest)
-               c->pkeys[SSL_PKEY_DSA_SIGN].digest = EVP_sha1();
+               if (!c->pkeys[SSL_PKEY_DSA_SIGN].digest)
+                       c->pkeys[SSL_PKEY_DSA_SIGN].digest = EVP_sha1();
 #endif
 #ifndef OPENSSL_NO_RSA
-       if (!c->pkeys[SSL_PKEY_RSA_SIGN].digest)
-               {
-               c->pkeys[SSL_PKEY_RSA_SIGN].digest = EVP_sha1();
-               c->pkeys[SSL_PKEY_RSA_ENC].digest = EVP_sha1();
-               }
+               if (!c->pkeys[SSL_PKEY_RSA_SIGN].digest)
+                       {
+                       c->pkeys[SSL_PKEY_RSA_SIGN].digest = EVP_sha1();
+                       c->pkeys[SSL_PKEY_RSA_ENC].digest = EVP_sha1();
+                       }
 #endif
 #ifndef OPENSSL_NO_ECDSA
-       if (!c->pkeys[SSL_PKEY_ECC].digest)
-               c->pkeys[SSL_PKEY_ECC].digest = EVP_sha1();
+               if (!c->pkeys[SSL_PKEY_ECC].digest)
+                       c->pkeys[SSL_PKEY_ECC].digest = EVP_sha1();
 #endif
+               }
        return 1;
        }
 
-#endif
 
 int SSL_get_sigalgs(SSL *s, int idx,
-                       int *psign, int *phash, int *psignandhash,
+                       int *psign, int *phash, int *psignhash,
                        unsigned char *rsig, unsigned char *rhash)
        {
-       if (s->cert->sigalgs == NULL)
+       const unsigned char *psig = s->cert->peer_sigalgs;
+       if (psig == NULL)
                return 0;
        if (idx >= 0)
                {
-               TLS_SIGALGS *psig;
-               if (idx >= (int)s->cert->sigalgslen)
+               idx <<= 1;
+               if (idx >= (int)s->cert->peer_sigalgslen)
                        return 0;
-               psig = s->cert->sigalgs + idx;
-               if (psign)
-                       *psign = psig->sign_nid;
-               if (phash)
-                       *phash = psig->hash_nid;
-               if (psignandhash)
-                       *psignandhash = psig->signandhash_nid;
-               if (rsig)
-                       *rsig = psig->rsign;
+               psig += idx;
                if (rhash)
-                       *rhash = psig->rhash;
+                       *rhash = psig[0];
+               if (rsig)
+                       *rsig = psig[1];
+               tls1_lookup_sigalg(phash, psign, psignhash, psig);
                }
-       return s->cert->sigalgslen;
+       return s->cert->peer_sigalgslen / 2;
+       }
+
+int SSL_get_shared_sigalgs(SSL *s, int idx,
+                       int *psign, int *phash, int *psignhash,
+                       unsigned char *rsig, unsigned char *rhash)
+       {
+       TLS_SIGALGS *shsigalgs = s->cert->shared_sigalgs;
+       if (!shsigalgs || idx >= (int)s->cert->shared_sigalgslen)
+               return 0;
+       shsigalgs += idx;
+       if (phash)
+               *phash = shsigalgs->hash_nid;
+       if (psign)
+               *psign = shsigalgs->sign_nid;
+       if (psignhash)
+               *psignhash = shsigalgs->signandhash_nid;
+       if (rsig)
+               *rsig = shsigalgs->rsign;
+       if (rhash)
+               *rhash = shsigalgs->rhash;
+       return s->cert->shared_sigalgslen;
        }
        
 
@@ -3107,3 +3459,262 @@ tls1_heartbeat(SSL *s)
        return ret;
        }
 #endif
+
+#define MAX_SIGALGLEN  (TLSEXT_hash_num * TLSEXT_signature_num * 2)
+
+typedef struct
+       {
+       size_t sigalgcnt;
+       int sigalgs[MAX_SIGALGLEN];
+       } sig_cb_st;
+
+static int sig_cb(const char *elem, int len, void *arg)
+       {
+       sig_cb_st *sarg = arg;
+       size_t i;
+       char etmp[20], *p;
+       int sig_alg, hash_alg;
+       if (sarg->sigalgcnt == MAX_SIGALGLEN)
+               return 0;
+       if (len > (int)(sizeof(etmp) - 1))
+               return 0;
+       memcpy(etmp, elem, len);
+       etmp[len] = 0;
+       p = strchr(etmp, '+');
+       if (!p)
+               return 0;
+       *p = 0;
+       p++;
+       if (!*p)
+               return 0;
+
+       if (!strcmp(etmp, "RSA"))
+               sig_alg = EVP_PKEY_RSA;
+       else if (!strcmp(etmp, "DSA"))
+               sig_alg = EVP_PKEY_DSA;
+       else if (!strcmp(etmp, "ECDSA"))
+               sig_alg = EVP_PKEY_EC;
+       else return 0;
+
+       hash_alg = OBJ_sn2nid(p);
+       if (hash_alg == NID_undef)
+               hash_alg = OBJ_ln2nid(p);
+       if (hash_alg == NID_undef)
+               return 0;
+
+       for (i = 0; i < sarg->sigalgcnt; i+=2)
+               {
+               if (sarg->sigalgs[i] == sig_alg
+                       && sarg->sigalgs[i + 1] == hash_alg)
+                       return 0;
+               }
+       sarg->sigalgs[sarg->sigalgcnt++] = hash_alg;
+       sarg->sigalgs[sarg->sigalgcnt++] = sig_alg;
+       return 1;
+       }
+
+/* Set suppored signature algorithms based on a colon separated list
+ * of the form sig+hash e.g. RSA+SHA512:DSA+SHA512 */
+int tls1_set_sigalgs_list(CERT *c, const char *str, int client)
+       {
+       sig_cb_st sig;
+       sig.sigalgcnt = 0;
+       if (!CONF_parse_list(str, ':', 1, sig_cb, &sig))
+               return 0;
+       return tls1_set_sigalgs(c, sig.sigalgs, sig.sigalgcnt, client);
+       }
+
+int tls1_set_sigalgs(CERT *c, const int *psig_nids, size_t salglen, int client)
+       {
+       unsigned char *sigalgs, *sptr;
+       int rhash, rsign;
+       size_t i;
+       if (salglen & 1)
+               return 0;
+       sigalgs = OPENSSL_malloc(salglen);
+       if (sigalgs == NULL)
+               return 0;
+       for (i = 0, sptr = sigalgs; i < salglen; i+=2)
+               {
+               rhash = tls12_find_id(*psig_nids++, tls12_md,
+                                       sizeof(tls12_md)/sizeof(tls12_lookup));
+               rsign = tls12_find_id(*psig_nids++, tls12_sig,
+                               sizeof(tls12_sig)/sizeof(tls12_lookup));
+
+               if (rhash == -1 || rsign == -1)
+                       goto err;
+               *sptr++ = rhash;
+               *sptr++ = rsign;
+               }
+
+       if (client)
+               {
+               if (c->client_sigalgs)
+                       OPENSSL_free(c->client_sigalgs);
+               c->client_sigalgs = sigalgs;
+               c->client_sigalgslen = salglen;
+               }
+       else
+               {
+               if (c->conf_sigalgs)
+                       OPENSSL_free(c->conf_sigalgs);
+               c->conf_sigalgs = sigalgs;
+               c->conf_sigalgslen = salglen;
+               }
+
+       return 1;
+
+       err:
+       OPENSSL_free(sigalgs);
+       return 0;
+       }
+
+static int tls1_check_sig_alg(CERT *c, X509 *x, int default_nid)
+       {
+       int sig_nid;
+       size_t i;
+       if (default_nid == -1)
+               return 1;
+       sig_nid = X509_get_signature_nid(x);
+       if (default_nid)
+               return sig_nid == default_nid ? 1 : 0;
+       for (i = 0; i < c->shared_sigalgslen; i++)
+               if (sig_nid == c->shared_sigalgs[i].signandhash_nid)
+                       return 1;
+       return 0;
+       }
+
+/* Check certificate chain is consistent with TLS extensions and is
+ * usable by server.
+ */
+int tls1_check_chain(SSL *s, X509 *x, EVP_PKEY *pk, STACK_OF(X509) *chain,
+                                                                       int idx)
+       {
+       int i;
+       int rv = CERT_PKEY_INVALID;
+       CERT_PKEY *cpk = NULL;
+       CERT *c = s->cert;
+       if (idx != -1)
+               {
+               cpk = c->pkeys + idx;
+               x = cpk->x509;
+               pk = cpk->privatekey;
+               chain = cpk->chain;
+               /* If no cert or key, forget it */
+               if (!x || !pk)
+                       goto end;
+               }
+       else
+               {
+               idx = ssl_cert_type(x, pk);
+               if (idx == -1)
+                       goto end;
+               }
+
+       /* Check all signature algorithms are consistent with
+        * signature algorithms extension if TLS 1.2 or later
+        * and strict mode.
+        */
+       if (TLS1_get_version(s) >= TLS1_2_VERSION
+               && c->cert_flags & SSL_CERT_FLAG_TLS_STRICT)
+               {
+               int default_nid;
+               unsigned char rsign = 0;
+               if (c->peer_sigalgs)
+                       default_nid = 0;
+               /* If no sigalgs extension use defaults from RFC5246 */
+               else
+                       {
+                       switch(idx)
+                               {       
+                       case SSL_PKEY_RSA_ENC:
+                       case SSL_PKEY_RSA_SIGN:
+                       case SSL_PKEY_DH_RSA:
+                               rsign = TLSEXT_signature_rsa;
+                               default_nid = NID_sha1WithRSAEncryption;
+                               break;
+
+                       case SSL_PKEY_DSA_SIGN:
+                       case SSL_PKEY_DH_DSA:
+                               rsign = TLSEXT_signature_dsa;
+                               default_nid = NID_dsaWithSHA1;
+                               break;
+
+                       case SSL_PKEY_ECC:
+                               rsign = TLSEXT_signature_ecdsa;
+                               default_nid = NID_ecdsa_with_SHA1;
+                               break;
+
+                       default:
+                               default_nid = -1;
+                               break;
+                               }
+                       }
+               /* If peer sent no signature algorithms extension and we
+                * have set preferred signature algorithms check we support
+                * sha1.
+                */
+               if (default_nid > 0 && c->conf_sigalgs)
+                       {
+                       size_t j;
+                       const unsigned char *p = c->conf_sigalgs;
+                       for (j = 0; j < c->conf_sigalgslen; j += 2, p += 2)
+                               {
+                               if (p[0] == TLSEXT_hash_sha1 && p[1] == rsign)
+                                       break;
+                               }
+                       if (j == c->conf_sigalgslen)
+                               goto end;
+                       }
+               /* Check signature algorithm of each cert in chain */
+               if (!tls1_check_sig_alg(c, x, default_nid))
+                       goto end;
+               for (i = 0; i < sk_X509_num(chain); i++)
+                       {
+                       if (!tls1_check_sig_alg(c, sk_X509_value(chain, i),
+                                                       default_nid))
+                               goto end;
+                       }
+               }
+
+       /* Check cert parameters are consistent */
+       if (!tls1_check_cert_param(s, x))
+               goto end;
+       /* In strict mode check rest of chain too */
+       if (c->cert_flags & SSL_CERT_FLAG_TLS_STRICT)
+               {
+               for (i = 0; i < sk_X509_num(chain); i++)
+                       {
+                       if (!tls1_check_cert_param(s, sk_X509_value(chain, i)))
+                               goto end;
+                       }
+               }
+       rv = CERT_PKEY_VALID;
+
+       end:
+       if (cpk)
+               {
+               if (rv && cpk->digest)
+                       rv |= CERT_PKEY_SIGN;
+               cpk->valid_flags = rv;
+               }
+       return rv;
+       }
+
+/* Set validity of certificates in an SSL structure */
+void tls1_set_cert_validity(SSL *s)
+       {
+       tls1_check_chain(s, NULL, NULL, NULL, SSL_PKEY_RSA_ENC);
+       tls1_check_chain(s, NULL, NULL, NULL, SSL_PKEY_RSA_SIGN);
+       tls1_check_chain(s, NULL, NULL, NULL, SSL_PKEY_DSA_SIGN);
+       tls1_check_chain(s, NULL, NULL, NULL, SSL_PKEY_DH_RSA);
+       tls1_check_chain(s, NULL, NULL, NULL, SSL_PKEY_DH_DSA);
+       tls1_check_chain(s, NULL, NULL, NULL, SSL_PKEY_ECC);
+       }
+/* User level utiity function to check a chain is suitable */
+int SSL_check_chain(SSL *s, X509 *x, EVP_PKEY *pk, STACK_OF(X509) *chain)
+       {
+       return tls1_check_chain(s, x, pk, chain, -1);
+       }
+
+#endif